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Sample records for cells u251 pten-mutant

  1. Effect of Human Cytomegalovirus Infection on Nerve Growth Factor Expression in Human Glioma U251 Cells

    Institute of Scientific and Technical Information of China (English)

    HAI-TAO WANG; BIN WANG; ZHI-JUN LIU; ZHI-QIANG BAI; LING LI; HAI-YAN LIU; DONG-MENG QIAN; ZHI-YONG YAN; XU-XIA SONG

    2009-01-01

    Objectives To explore the change of endogenic nerve growth factor (NGF) expression in human glioma cells infected with human cytomegalovirus (HCMV). Methods U251 cells were cultured in RPMI 1640 culture medium and infected with HCMV AD169 strain in vitro to establish a cell model of viral infection. Morphologic changes of U251 cells were observed under inverted microscope before and after infection with HCMV. Expression of NGF gene and protein of cells was detected by RT-PCR and Western blotting before and after infection with HCMV. Results The cytopathic effects of HCMV-infected cells appeared on day 5 after infection. However, differential NGF expression was evident on day 7. NGF expression was decreased significantly in U251 cells on day 7 after infection in comparison with control group (P<0.05). Conclusion HCMV can down-regulate endogenous NGF levels in human glioma cell line U251.

  2. Cytotoxic activity of allogeneic natural killer cells on U251 glioma cells in vitro.

    Science.gov (United States)

    Guo, Meng; Wu, Tingting; Wan, Lixin

    2016-07-01

    The present study aimed to observe the cytotoxic activity of allogeneic natural killer (NK) cells on U251 glioma cells and to investigate their mechanism of action to establish an effective treatment strategy for neuroglioma. Cell survival curves, colony formation assays and karyotype analysis were performed to investigate the characteristics of U251 glioma cells. The present study demonstrated that natural killer group 2, member D (NKG2D)‑major histocompatibility complex class I‑related chain A/B (MICA/B) interactions contributed to the cytotoxic effect of NK cells on K562 and U251 cells. In antibody‑blocking assays to inhibit NKG2D ligands, the cytotoxic activity was not completely attenuated, which suggested that other signaling pathways contribute to the cytotoxic activity of NK cells on tumor cells in addition to the NKG2D‑mediated activity. The present study identified that the expression levels of NKG2D ligands on the surface of target cells influenced the strength of the NK cell immune response. Furthermore, allogeneic NK cells were observed to kill glioma cells in vitro, and this anticancer activity is associated with the rate of NKG2D expression on the surface of glioma cells.

  3. siRNA epidermal growth factor receptor silencing in U251 glioma cells

    Institute of Scientific and Technical Information of China (English)

    Chunsheng Kang; Zhiyong Zhang; Zhifan Jia; Qiang Huang; Guangxiu Wang; Mingzhe Qiu; Peiyu Pu

    2008-01-01

    BACKGROUND: Dicer, a large multidomain ribonuclease, is responsible for processing double-stranded RNAs (dsRNAs) to 20-bp-long small interfering RNAs (siRNAs), which act as effectors during RNA interference (RNAi). OBJECTIVE: To observe the efficacy of siRNA cocktails generated by recombinant human Dicer on the down-regulation of epidermal growth factor receptor (EGFR) expression in human glioma cells. DESIGN, TIME AND SETTING: The following in vitro experiment was performed at the Department of Neurosurgery, Tianjin Medical University General Hospital and Laboratory of Neuro-Oncology, Tianjin Neurological Institute. MATERIALS: Mini-RNA isolation kit, human placenta complimentary DNA (cDNA) was produced by Tiangen Biotech (Beijing, China), human glioblastoma U251-MG cells were produced by the Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences. METHODS: A PCR product from the human EGFR, which corresponded to the tyrosine kinase domain of the 3'-end fragment, was used as the T7-promotor for in vitro transcription, siRNA cocktails were generated by in vitro dicing of double stranded RNA. A total of 500, 250 and 125 μg siRNA cocktails were transiently transfected into U251 glioma cells through the use of the GeneSilencer. MAIN OUTCOME MEASURE: Expression of EGFR was detected by real-time PCR. RESULTS: The total PCR product of the human EGFR, corresponding to the tyrosine kinase domain, is approximately 680 bp in length. The PCR transcriptants included GCC leader sequences and a T7 promoter sequence, with a fragment of EGFR cDNA at the center. The T7 promoter was prepared for in vitro transcription of dsRNA. After dicing for 24 hours, the 21-nt siRNA cocktails were verified by 4% agarose gel. The difference between threshold cycle of a sample assay and threshold cycle of the corresponding endogenous reference (△ Ct) among parental U251 cells and cells transfected with different doses of siRNA cocktails were determined to be 3.06, 7.35, and 10

  4. Tumstatin transfected into human glioma cell line U251 represses tumor growth by inhibiting angiogenesis

    Institute of Scientific and Technical Information of China (English)

    YE Hong-xing; YAO Yu; JIANG Xin-jun; YUAN Xian-rui

    2013-01-01

    Background Angiogenesis is a prerequisite for tumor growth and plays an important role in rapidly growing tumors,such as malignant gliomas.A variety of factors controlling the angiogenic balance have been described,and among these,the endogenous inhibitor of angiogenesis,tumstatin,has drawn considerable attention.The current study investigated whether expression of tumstatin by glioma cells could alter this balance and prevent tumor formation.Methods We engineered stable transfectants from human glioma cell line U251 to constitutively secrete a human tumstatin protein with c-myc and polyhistidine tags.Production and secretion of the tumstatin-c-myc-His fusion protein by tumstatin-transfected cells were confirmed by Western blotting analysis.In the present study,we identify the anti-angiogenic capacity of tumstatin using several in vitro and in vivo assays.Student's t-test and one-way analysis of variance (ANOVA) test were used to determine the statistical significance in this study.Results The tumstatin transfectants and control transfectants (stably transfected with a control plasmid) had similar in vitro growth rates compared to their parental cell lines.However,the conditioned medium from the tumstatin transfected tumor cells significantly inhibits proliferation and causes apoptosis of endothelial cells.It also inhibits tube formation of endothelial cells on Matrigel.Examination of armpit tumors arising from cells overexpressing tumstatin repress the growth of tumor,accompanying the decreased density of CD31 positive vessels in tumors ((5.62±1.32)/HP),compared to the control-transfectants group ((23.84+1.71)/HP) and wild type U251 glioma cells group ((29.33+4.45)/HP).Conclusion Anti-angiogenic gene therapy using human tumstatin gene may be an effective strategy for the treatment of glioma.

  5. EFFECTS OF p16INK4 GENE ON CHEMOSENSITIVITY OF HUMAN GLIOMA U251 CELL LINE TO TENIPOSIDE

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective: To determine the effects on the cell growth, tumorigenicity and chemosensitivity of p16/CDK4I in human glioma. Methods: p16 gene was transfected into U251 cells by lipofectin. Expression of exogenous p16 gene was confirmed by immunohistochemistry and Northern blot. The effects of exogenous p16 gene on the growth and chemosensitivity to teniposide were examined. Results: Expression of exogenous p16 gene inhibited the growth dramatically in vitro. G1 arrest of tumor cells was observed. However, wt p16-positive U251 was less sensitive than control cell lines and the number of apoptotic cells after chemotherapy was reduced. Conclusion: The expression of exogenous p16 gene could inhibit the growth of glioma. On the other hand, the chemosensitivity to teniposide of p16-positive U251 was decreased.

  6. Downregulation of ROCK2 through Nanocomplex Sensitizes the Cytotoxic Effect of Temozolomide in U251 Glioma Cells

    OpenAIRE

    Xiaojun Wen; Amin Huang; Zhonglin Liu; Yunyun Liu; Jingyang Hu; Jun Liu; Xintao Shuai

    2014-01-01

    OBJECTIVE: Rho-associated coiled-coil kinase 2 (ROCK2) is an attractive therapeutic target because it is overexpressed in many malignancies, including glioma. Therefore, we designed the current study to determine whether the downregulation of ROCK2 would sensitize the cytotoxic effect of temozolomide (TMZ) in U251 cells. METHODS: Glycol-polyethyleneimine (PEG-PEI) was used to deliver siROCK2 to U251 cells, and the physical characteristics of the PEG-PEI/siROCK2 complex (referred to as the siR...

  7. Effects of temozolomide chemotherapy on CD133+ cells in glioma U251%替莫唑胺化疗对胶质瘤U251中CD133+细胞的影响

    Institute of Scientific and Technical Information of China (English)

    杨伟现; 向定朝; 王存祖; 周月鹏; 欧阳琦; 张志坚; 许慧中; 陆晓峰

    2012-01-01

    目的 探讨化疗耐药与肿瘤干细胞之间的关系.方法 分析替莫唑胺(TMZ)作用前后胶质瘤U251中CD133蛋白表达及阳性细胞数量的变化.通过MTT实验评估U251细胞对TMZ的敏感性.利用免疫荧光染色和Western blot检测TMZ作用前后U251细胞中CD133、巢蛋白(nestin)、神经元特异性烯醇化酶(NSE)、神经胶质细胞纤维酸性蛋白(GFAP)等蛋白表达.结果 U251细胞中未加入TMZ组的CD133+细胞比例约为0.060±0.003,明显低于加入TMZ组的0.337±0.012(P<0.05).在TMZ作用后,CD133和nestin表达明显增加,而GFAP和NSE表达明显减少(P<0.05).结论 胶质瘤U251细胞株中存在CD133+细胞,大部分具有脑肿瘤干细胞特性;在TMZ作用后,这类细胞比例增加,提示其与化疗耐药有关.%Objective To explore the relationship between chemotherapy resistance and cancer stem cells. Methods The changes of the number and protein expression were analyzed before and after the CD133+ cells in glioma U251 were intervented by temozolomide(TMZ). The expressions of CD133,nestin,neuron-specific enolase(NSE),glial fibrillary acidic protein(GFAP) and other proteins in glioma U251 cells were detected by immunofluorescence and Western blot. Results U251 cells in the TMZ group did not join The proportion of CD133+ cells was significantly greater in the U251 cells with TMZ intervention than that without(0. 337±0.012 vs. 0. 060 + 0.003) (P<0. 05). After TMZ intervention, the proportion of nestin-positive cells in the CD133+ cells were increased,but GFAP and NSE-positive cells were decreased(P<0. 05). Conclusion There CD133+cells in the U251 glioma cell lines,majority of which have the properties of brain tumor stem cells. After TMZ intervention, an increased proportion of the CD133+ cells suggests its relationship with chemotherapy-related drug resistance.

  8. Downregulation of ROCK2 through nanocomplex sensitizes the cytotoxic effect of temozolomide in U251 glioma cells.

    Directory of Open Access Journals (Sweden)

    Xiaojun Wen

    Full Text Available OBJECTIVE: Rho-associated coiled-coil kinase 2 (ROCK2 is an attractive therapeutic target because it is overexpressed in many malignancies, including glioma. Therefore, we designed the current study to determine whether the downregulation of ROCK2 would sensitize the cytotoxic effect of temozolomide (TMZ in U251 cells. METHODS: Glycol-polyethyleneimine (PEG-PEI was used to deliver siROCK2 to U251 cells, and the physical characteristics of the PEG-PEI/siROCK2 complex (referred to as the siROCK2 complex were investigated. The transfection efficiency and cell uptake were determined by flow cytometry (FCM and confocal laser microscopy (CLSM, respectively. U251 cells were then treated with 100 μM TMZ, siROCK2 complexes or their combination. The apoptosis rate and cell migration were measured by FCM and wound-healing assay, respectively. The levels of Bax, Bcl-2, cleaved caspase-3, MMP-2, and MMP-9 were detected to analyze the degrees of apoptosis and migration. RESULTS: Our results revealed that the characteristics of the siROCK2 complexes depended closely on the N/P ratios. PEG-PEI served as a good vector for siROCK2 and exhibited low cytotoxicity toward U251 cells. The CLSM assay showed that the siROCK2 complexes were successfully uptaken and that both the protein and mRNA levels of ROCK2 were significantly suppressed. Furthermore, the combination treatment induced a higher apoptosis rate and markedly increased the gap distance of U251 cells in the wound-healing assay. Levels of the proapoptotic proteins Bax and cleaved caspase-3 were significantly increased, whereas levels of the antiapoptotic protein Bcl-2 and the migration-related proteins MMP-2 and MMP-9 were significantly reduced by the combination treatment compared with either treatment alone. CONCLUSIONS: In conclusion, our results demonstrate that the combination of TMZ and siROCK2 effectively induces apoptosis and inhibits the migration of U251 cells. Therefore, the combination of TMZ

  9. 过表达TAP1上调人胶质瘤细胞株U251 HLA-I的表达%Overexpression of TAP1 up-regulates HLA-I in human glioma U251 cells

    Institute of Scientific and Technical Information of China (English)

    欧阳乐平; 张善义; 李军亮; 许新科; 翁胤仑; 郑眉光; 王圣文; 李方成

    2013-01-01

    AIM: To investigate the relationship between the overexpression of transporter associated with antigen processing 1 (TAP1) and the human leukocyte antigen I (HLA-I). METHODS: The full length of TAP1 gene was obtained from the cDNA library. The lentiviral vector pSIN-EF2-IRES-GFP-puro was digested by BamH I and EcoR I, and the full length of TAP1 gene was inserted into the vector by T4 DNA ligase. Subsequently, the recombinant plasmid was transformed into Escheriehia coli DH5α cells and the correct transformant was selected. The recombinant plasmid and the Lenti-X HTX packaging mixture were co-transfected into 293T cells, and the virus particle was acquired. Human glioma U251 cells were transfected with the lentivirus. The expression of TAP1 and HLA-I was determined by real-time fluorescence quantitative PCR, Western blotting and flow cytometric analysis. RESULTS; TAP1 gene was successfully transfected into the U251 cells and stably expressed in the cell line. The expression of TAP1 in U251 cells at mRNA and protein levels increased by ( 8. 73 ± 1. 07) and (11. 71 ± 0. 83 ) folds, respectively. As a result, the mRNA expression of HLA-A, HLA-B, HLA-C (heavy chain) and β2-microglobulin (light chain) was up-regulated by (3. 51 ±0. 36) , (4. 78 ±0. 85) , (2.94 ±0.28) and (3. 23 ±0. 24) folds, respectively. The protein expression of HLA-I also increased to (3.14 ±0. 53) fold. The surface expression of HLA-I on the U251 cells transfected with TAP1 gene was largely enhanced as well. CONCLUSION : Overexpression of TAP1 up-regulates the expression of HLA-I. TAP1 plays an important role in HLA-I pro-cessing pathway.%目的:探讨抗原提呈相关转运蛋白1(TAPl)过表达对人胶质瘤细胞株U251人类白细胞抗原I(HLA-I)表达的影响.方法:培养U251细胞,构建慢病毒载体并转染U251细胞,获得稳定高表达TAP1的细胞株并设立转染空载体对照组,分别收集U251细胞组、空载体对照组和TAPl基因转染细胞组

  10. Mechanism of thalidomide to enhance cytotoxicity of temozolomide in U251-MG glioma cells in vitro

    Institute of Scientific and Technical Information of China (English)

    GAO Song; YANG Xue-jun; ZHANG Wen-gao; JI Yan-wei; PAN Qiang

    2009-01-01

    Background Glioma is the most common primary brain tumor with poor prognosis. Temozolomide has been used with thalidomide to treat gliomas. We investigated the synergistic mechanism of these two drugs in vitro.Methods Human malignant glioma cells U251-MG were cultured and assigned to four groups with different treatments for 3 days: temozolomide group (100 pmol/L), thalidomide group (100 pg/L), temozolomide (100 IJmol/L) plus thalidomide group (100 pg/L) and control group. MTT assay was applied to evaluate the cell viability. Cell cycle was analyzed by flow cytometry. The ultra-structural features of autophagosomes were observed with electron microscope. Acridine orange and monodansylcadavedne were adopted to label autophagosomes and flow cytometry was applied for quantification of autophagosomes. The expression of autophagy-associated protein was detected by Western blotting.Results Proliferation of tumor cell was obviously suppressed by temozolomide with thalidomide treatment than by either drug used alone (P=-0.000 for each day). The combination treatment induced cell cycle arrest at G0/G1 phase.Typical autophagic ultra-structural character was found after the combined treatment. Thalidomide promoted the autophagy induced by temozolomide. The autophagy-associated proteins - microtubule associated protein 1 light chain 3 (MAPILC3) and Beclinl were more significantly up-regulated by the combined treatment than temozolomide used alone (MAP1LC3, P=-0.000; Beclinl, P=-0.004). The expression level of phosphatase and tensin homolog deleted on chromosome ten (PTEN), which promoted autophagy by suppressing PI3K/Akt/mTOR signaling pathway, was elevated by thalidomide (thalidomide group: P=-0.000; combined group: P=0.002).Conclusions Thalidomide enhances the cytotoxicity of temozolomide by promoting the autophagy induced by temozolomide. Contributing to the up-regulation of PTEN by thalidomide, the expression of autophagy associated protein-MAP1LC3 and Beclinl was enhanced

  11. 替莫唑胺对人胶质瘤细胞系U251细胞miR125b的影响%Temozolomide in glioblastoma cells U251 affect miR-125b expression

    Institute of Scientific and Technical Information of China (English)

    程峰; 石磊; 贡伟一; 刘华; 潘天鸿

    2014-01-01

    目的:探讨替莫唑胺( TMZ)对人胶质瘤细胞系U251细胞的miRNA125b的表达影响。方法将人胶质瘤细胞系U251细胞分成空白对照组、TMZ组,TMZ组设10、25、50、100、200、400、600μmol/L组。各组分别作用于24、48、72 h后进行实时定量PCR( Real-time PCR)检测miRNA-125b的表达水平;用MTT比色法检测细胞活力;流式细胞仪检测细胞周期和凋亡率。结果荧光定量PCR检测结果显示:替莫唑胺作用24 h后, miRNA125b表达变化不明显;48 h后对miR-125b表现出抑制作用, miR-125b对U251细胞的抑制率呈良好的时间-剂量效应关系,其Ic 50为76μmol,初始抑制浓度为50μmol;流式细胞仪检测显示,U251细胞经TMZ作用后出现G2/M期阻滞,但促凋亡作用并不显著。结论在TMZ对胶质瘤细胞治疗过程中,hsa-miR-125b的表达随着治疗剂量而被抑制,miR-125b可以作为TMZ在用药过程中效果的检测以及抗药性反应的参考依据。%Objective To investigate the temozolomide(TMZ) affect on the expression of hsa-miR-125b human neureblastoma cell line U251 cells.Method U251 cells we treated 7 different concentrations of TMZ (10、25、50、100、200、400、600 μmol/L) 72 h, hsa-miR-125 expression level was identified by quantitve real time PCR ( qRT-PCR) .Cell viability was accessed by using colorimotrlc MTT assay Cell cycle progression and apoptosis ratio are measured by using flow cytometry .Results After TMZ affect 24h, the changes of miRNA-125b expression were unconspic-uous, and after 48h, the expression of miRNA-125b was inhibited.The IC50 of TMZ Was 76 mol/L.The relationship between the expression level of miR-125b and the inhibition rate of U251 cells was a perfect time to dose response . There were significant difference between the control group and the groups over 50 mol/L(P<0.01). Flow cytometry showed that U251 cells responded to TMZ by undergoing G2/M arrest and very few cells show apoptosis

  12. Starvation after Cobalt-60 γ-Ray Radiation Enhances Metastasis in U251 Glioma Cells by Regulating the Transcription Factor SP1.

    Science.gov (United States)

    Zhao, Tuo; Wang, Hailong; Ma, Hong; Wang, Hao; Chen, Bo; Deng, Yulin

    2016-04-05

    Radiation is of clinical importance during glioma therapy; however, vasculature damage is observed over the treatment course. This type of tissue damage might lead to starvation conditions, affecting tumor metastasis. To test this possibility, we compared starvation conditions in conjunction with radiation treatment to monitor metastatic ability in the U251 glioma cell line. Transcriptome, western blot, and immunofluorescence analyses were used to measure the RNA and protein expression changes of the U251 cells after various treatments. We found that starvation combined with radiation treatment yielded the most significant expression changes in metastasis-related factors compared to that in the control groups. In addition, a metastasis assay was used to directly measure the metastatic ability of the treated cells, which confirmed that the U251 cells treated with starvation combined with radiation possessed the highest metastatic ability. Furthermore, bioinformatics analysis demonstrated that SP1 represented a common transcription factor associated with changes in metastasis-related factors. Blocking SP1 activity by an inhibitor suppressed the starvation-plus-radiation treatment-mediated enhancement of U251 cell metastasis. Our study provides the first evidence that starvation caused by radiation might play a significant role in enhancing the ability of the glioma cell line U251 to metastasize via regulation of the transcription factor SP1.

  13. Starvation after Cobalt-60 γ-Ray Radiation Enhances Metastasis in U251 Glioma Cells by Regulating the Transcription Factor SP1

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    Tuo Zhao

    2016-04-01

    Full Text Available Radiation is of clinical importance during glioma therapy; however, vasculature damage is observed over the treatment course. This type of tissue damage might lead to starvation conditions, affecting tumor metastasis. To test this possibility, we compared starvation conditions in conjunction with radiation treatment to monitor metastatic ability in the U251 glioma cell line. Transcriptome, western blot, and immunofluorescence analyses were used to measure the RNA and protein expression changes of the U251 cells after various treatments. We found that starvation combined with radiation treatment yielded the most significant expression changes in metastasis-related factors compared to that in the control groups. In addition, a metastasis assay was used to directly measure the metastatic ability of the treated cells, which confirmed that the U251 cells treated with starvation combined with radiation possessed the highest metastatic ability. Furthermore, bioinformatics analysis demonstrated that SP1 represented a common transcription factor associated with changes in metastasis-related factors. Blocking SP1 activity by an inhibitor suppressed the starvation-plus-radiation treatment-mediated enhancement of U251 cell metastasis. Our study provides the first evidence that starvation caused by radiation might play a significant role in enhancing the ability of the glioma cell line U251 to metastasize via regulation of the transcription factor SP1.

  14. Characterization of radioresistant variant from U251 human glioblastoma cell line and the role of antioxdant enzymes in its radioresistancy

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    Lee, Hyung Chahn; Park, In Chul; Park, Myung Jin; Woo, Sang Hyeok; Rhee, Chang Hum; Hong, Seok-II [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)

    2004-07-01

    To investigate the radioresistant mechanism in glioblastoma multiforme(GBM), we isolated the radioresistant clone (RRC) from U251 human glioblastoma cell line by exposing to repeated fractions of 3 Gy {gamma}-radiation for six months. RRC had higher radioresistance than the parent cell line as measured by clonogenic survival assay. FACS analysis showed that RRC had a delayed G2 arrest after radiation. Antioxidant enzymes, such as SOD, catalase, glutathione peroxidase (GPX), glutathione reductase (GR), were activated up to 5 folds in RRC after radiation. Erk 1/2 activation was higher in RRC than in the parent cell. Therefore, radioresistancy in RRC might be due to the delayed cell cycle, the coordinated high activation of antioxidant enzyme rather than a single enzyme alone,and higher activation of Erk 1/2.

  15. Localization of phosphorylated TrkA in carrier vesicles involved in its nuclear translocation in U251 cell line

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A number of transmembrane receptors are targeted to the nucleus and convincingly localized therein. However, what remains a conundrum is how these cell-surface receptors end up in the nucleus. In this study, we reported that the transmembrane receptor phosphorylated TrkA was located in a series of carrier vesicles, including ring-like vesicles near the plasma membrane, large core vesicles and small dense core vesicles around the nuclei, as well as in the nucleus in human glioma cell line U251 using immunocytochemistry and immunofluorescence staining. Meanwhile, we also showed that small dense core vesicles budded from large core vesicles, and interacted with the nuclear envelope. Accordingly, our results suggested that such a series of membrane compartments might be involved in the pathway of nuclear translocation of the transmembrane receptor TrkA.

  16. Apoptosis of Glioblastoma U251 Cells Induced by Carmustine Combined All-trans Retinoic Acid via Regulating Cyclin E and p27kip 1

    Institute of Scientific and Technical Information of China (English)

    QI Bin; WEIJun; HU Guo-zhang; YANG Hong-fa; BI Chun-hua; SUN Zhi-gang; TIAN Yu

    2011-01-01

    The effect and mechanism of carmustine(BCNU) combined with all-trans retinoic acid(ATRA) on the apoptosis of human glioblastoma U251 cells were investigated by means of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay,flow cytometry,reverse transcription-polymerase chain reaction(RT-PCR) and Western blot analysis.The results show that BCNU or ATRA shows time- and dose-dependent inhibition effects on human glioblastoma U251 cells and the combination of BCNU with ATRA shows an synergistic inhibition effect on human glioblastoma U251 cells,and the combined BCNU and ATRA can significantly inhibit the proliferation of human glioblastoma U251 cells,and induce the apoptosis of them,making the cells arrest in the stage of G1 phase,the stage of S and G2 phases decline,the rate of the apoptosis of human glioblastoma U251 cells increase,the corresponding mRNA expression of cyclin E and cyclin-dependent kinase 2(CDK2) downregulated and the corresponding mRNA expression of p27kip 1 unregulated.In addition,the combined BCNU and ATRA reduced the protein expression of nuclear factor kappa B(NF-kB).Taken together,these results suggest that the treatment of human glioblastoma U251 cells with a combination application of ATRA and BCNU can exert synergistic effect,the course of this kind of combination chemotherapy may likely be associated with multiple molecular mechanisms for apoptosis,furthermore,the cyclin E and p27kip 1 should be considered as novel targets for controlling the growth of glioblastoma cells.

  17. 塞来昔布联合替莫唑胺对胶质瘤U251细胞作用研究%Effect of celecoxib combined with temozolomide on proliferation and apoptosis of glioma cell line U251 cells

    Institute of Scientific and Technical Information of China (English)

    何远志; 徐国政

    2012-01-01

    Objective To study the curative effects of celecoxib combined with antitumor drugs on gliomas and its mechanism. Methods The human glioma cell lines U251 cells were cultured and they treated with celecoxib or temozolomide or both the drugs. The cell morphologic change was observed under the optical microscope. The proliferation of U251 cells was determined by methyl thiaszolyl tetrazoliu assay. The migration ability of U251 cells was determined by wound healing test. The apoptosis of U251 cells were evaluated by flow cytometry with PI - Annexin V staining. The expression of Bcl-2 and Bax in U251 cells were detected by western blot. Results The morphologic changes occurred in U251 cells treated with celecoxib or temozolomide or both the drugs, but the morphologic change in U251 cells treated by both the drugs were most significant. The inhibitory effect of celecoxib combined with temozolomide on U251 cells proliferation was significantly stronger than those of celecoxib or temozolomide (P<0.01). The apoptosis rate in U251 cells treated by both the drugs was significantly higher than those in U251 cells treated by celecoxib or temozolomide alone (P<0.01). The celecoxib combined with temozolomide more significantly inhibited the migration of U251 cells compared to celecoxib or temozolomide alone. The level of Bax expression was significantly higher and the level of Bcl-2 expression was significantly lower in U251 cells treated by both the drugs than those in U251 cells treated by celecoxib or temozolomide alone. Conclusion The combinative application of celecoxib and temozolomide can promote the apoptosis and inhibit the proliferation and migration of U251 cells in a synergistic manner. These effects of celecoxib combined with temozolomide may be related with the upregnlation of Bax expression and down regulation of Bcl-2 expression.%目的 探讨环氧合酶抑制剂塞来昔布联合抗肿瘤药物替莫唑胺对神经胶质瘤细胞系U251细胞的体外抗瘤

  18. Induction of apoptosis in glioblastoma cell line U251 of Cinobufacini%华蟾素诱导人胶质瘤细胞U251凋亡的作用机制研究

    Institute of Scientific and Technical Information of China (English)

    赵志远

    2012-01-01

    目的 研究观察华蟾素(Cinobufacini)对体外培养人胶质瘤细胞U251增殖抑制作用,并初步探讨其诱导U251细胞凋亡的分子机制.方法 平皿克隆形成法测定不同浓度华蟾素对U251细胞锚定依赖性生长能力的影响;使用Wester Blot法观察不同浓度华蟾素处理人胶质瘤细胞48小时后,Bcl-2、Bax蛋白表达变化情况.结果 平皿克隆法显示:华蟾素抑制人胶质瘤细胞U251生长,呈剂量依赖性;Wester Blot显示随着药物浓度升高,华蟾素可以逐渐抑制Bcl-2的蛋白表达,活Bax蛋白表达.结论 华蟾素有诱导人胶质瘤细胞U251细胞凋亡的作用,其机制可能Bcl-2/Bax比值的下调,促进细胞凋亡有关.

  19. Influence of hyperbaric oxygen combining Temozolomide on human glioblastoma cell line U251%高压氧联合替莫唑胺对胶质瘤U251细胞的影响

    Institute of Scientific and Technical Information of China (English)

    曹侃; 袁志诚; 陆新宇; 李慧勇

    2012-01-01

    Objective To discuss the influence and mechanism on hyperbarie oxygen ( HBO) combining Temozolomide with human glioblastoma cell line U251. Method The cells were divided into four groups,A group is HBO combining Temozolomide,B group is HBO,C group is Temozolomide and D group is control group. By simulation of hypoxia microenviroment in vitro, the rate of growth inhibiting is investigated by MTT method. The rate of cell death is observed by PI staining. The rate of apoptosis is analyzed by the flow cytometry. Elasia method is used to detect the expression of hypoxia-inducible factorl-α (HIFl-α) and Multidrug resistance-associated protein-1 ( MRP-1). Results The group of HBO combining Temozolomide is obviously higher than others in rate of growth inhibiting, rate of cell death, rate of apoptosis, the results have statistics differences(P 0. 05) , but to others it has statistics value (P < 0. 05). Conclusion HBO can enhance the chemotherapy effect of temozolomide, it can correct the hypoxic microenvironment and reduce the expression of HIFl-α and MRP-1 ,these may be the key to effect.%目的 研究高压氧( Hyperbaric Oxygen,HBO)联合替莫唑胺(Temozolomide)对人神经胶质瘤U251细胞株的的影响及其机制.方法 实验分为4组:A组高压氧联合替莫唑胺组、B组高压氧组、C组替莫唑胺组、D组对照组.通过体外模拟缺氧微环境,用四甲基偶氮唑蓝法(MTT法)、碘化丙啶(PI)染色法、流式细胞仪分别检测细胞生长抑制率、细胞死亡率、细胞凋亡率.Elisa法检测缺氧诱导因子1-α(HIF1-α)和多药耐药相关蛋白-1(MRP-1)的表达情况.结果 1高压氧联合替莫唑胺组在细胞生长抑制率、细胞死亡率和细胞凋亡率上明显高于其他组,数值均有统计学意义(P<0.05).2高压氧联合替莫唑胺组与高压氧组在HIF1-α和MRP-1上无统计学意义(P>0.05),与其他组有统计学意义(P<0.05).结论 高压氧够增强替莫唑胺化疗效果,高压氧纠

  20. The effects of TSA combined with HSV-1 on proliferation and apoptosis of U251 cells%曲古抑菌素A联合单纯疱疹病毒Ⅰ型对U251细胞增殖、凋亡的影响

    Institute of Scientific and Technical Information of China (English)

    许强华; 陈新军

    2012-01-01

    Objective To observe the effects of trichostain A (TSA) combined with herpes simplex virus-1 ( HSV-1 ) on proliferation and apoptosis in U251 cells in vitro.Methods U251 cells in vitro were treated separately with 0.5 × 10-3 μmol/L TSA (TSA group),10 MOI HSV-1 (HSV-1 group),and 0.5 × 10-3 μmol/L TSA combined with 10 MOI HSV-1 (TSA + HSV-1 group) for 72 h.The methyl thiazol tetrazolium (MTT) assay was used to observe the proliferation of U251 cells.The cellular morphological changes were observed under a microscope.The apoptosis rate was analyzed by using flow cytometry.Results In TSA group,HSV-1 group,TSA + HSV-1 group,the proliferation inhibition rate of the U251 cells was (48.0t1.8)%,(18.0 ±3.1)%,and (58.0t5.8)%; Apoptosis rate was (47.4±3.5)%,(29.6 ±3.0)%,and (59.6 ±4.0)% respectively.The inhibitory effects of proliferation or apoptosis in TSA + HSV-1 group was stronger than TSA group or HSV-1 group ( P < 0.01 ).Conclusion TSA combined with HSV-1 has a synergistic killing effect on cultured U251 cells.%目的 以体外培养的U251细胞为模型,观察曲古抑菌素A(TSA)联合单纯疱疹病毒Ⅰ型( HSV-1)对肿瘤细胞增殖、凋亡的影响.方法 以0.5 ×10-3μmol/L TSA和10 MOI HSV-1及0.5 × 101 μmol/L TSA与10 MOIHSV-1组合作用于U251人胶质瘤细胞,72 h后噻唑蓝(MTT)比色法检测各组细胞增殖情况,显微镜下观察各组细胞形态,流式细胞仪检测各组细胞的凋亡情况.结果 单一TSA组、单一HSV-1组、TSA与HSV-1联合组U251细胞增殖抑制率分别为(48.0±1.8)%、(18.0±3.1)%、(58.0±5.8)%;凋亡率分别为(47.4±3.5)%、(29.6±3.0)%、(59.6±4.0)%.TSA与HSV-1联合组U251细胞增殖抑制率及凋亡率明显高于单一使用TSA或HSV-1组(P<0.01).结论 TSA联合HSV-1对体外培养的U251细胞具有协同或叠加杀伤作用.

  1. 乳腺丝氨酸蛋白酶抑制剂基因在胶质瘤细胞株U87、U251中表达沉默的表观遗传学机制%Epigenetics of silenced expression of maspin in glioma cell lines U87 and U251

    Institute of Scientific and Technical Information of China (English)

    刘泓渊; 屈鸣麒; 余聚; 兰青; 步星耀

    2014-01-01

    Objective To study the relationship between the silenced expression of mammary serine protease inhibitor (maspin) and epigenetics in human glioma cell lines U87 and U251.Methods Reverse transcription polymerase chain reaction (RT-PCR) and Western blotting were used to examine the expression of maspin.Methylation status of the maspin promoter was detected by methylation-specific polymerase chain reaction (MSP) and bisulphite genomic sequencing.RT-PCR was used to examine the expression of maspin after U87 and U251 cells were treated with 12 (or 15) μmol/L 5-Aza-2-deoxyeytidine (5-Aza-dC) and/or 500 nmol/L trichostatin A (TSA).Results A CpG island in the 5' promoter region of maspin was methylated.Maspin was silenced in human glioma cell lines U87 and U251.The relative intensity of maspin was 0.030 3 ±0.000 6,0.019 6 ±0.001 6,and 0.052 6 ±0.003 4 in 5-Aza-DC,TSA,and 5-Aza-DC plus TSA pretreated U87 cells,and 0.001 2 ± 0.000 1 in control group.The relative intensity of maspin was 0.012 2 ± 0.000 8,0.024 9 ± 0.001 2,and 0.038 4 ± 0.003 1 in 5-Aza-DC,TSA,and 5-Aza-DC plus TSA pretreated U251 cells,and 0.002 2 ± 0.00 3 in control goup.U87,and U251could could be restored by treatment with 5-Aza-DC and/or TSA (P < 0.01).Conclusion Maspin is silenced by promoter methylation and histone modification,and 5-Aza-DC and/or TSA can restore the transcription of maspin in U87 and U251 cells.%目的 探讨乳腺丝氨酸蛋白酶抑制剂基因(maspin)在人胶质瘤细胞株U87、U251中沉默与表观遗传学关系.方法 运用逆转录-聚合酶链反应( RT-PCR)、Western blot检测maspin基因在U87、U251的表达.甲基化特异性聚合酶链反应(MSP)测定maspin基因启动子区区域甲基化状态.同时运用亚硫酸氢盐测序法(BSP)检测maspin基因启动子区甲基化CpG位点.RT-PCR检测12 μmol/L 5-氮杂-2’-脱氧胞苷(5-Aza-DC)和/或500 nmol/L曲古霉素(TSA)、15 μmol/L 5-Aza-DC/或500 nmol/L TSA分别处理U87、U251

  2. Synthesis of tetrahydrohonokiol derivates and their evaluation for cytotoxic activity against CCRF-CEM leukemia, U251 glioblastoma and HCT-116 colon cancer cells.

    Science.gov (United States)

    Bernaskova, Marketa; Kretschmer, Nadine; Schuehly, Wolfgang; Huefner, Antje; Weis, Robert; Bauer, Rudolf

    2014-01-20

    Biphenyl neolignans such as honokiol and magnolol, which are the major active constituents of the Asian medicinal plant Magnolia officinalis, are known to exert a multitude of pharmacological and biological activities. Among these, cytotoxic and tumor growth inhibitory activity against various tumour cell lines are well-documented. To further elucidate the cytotoxic effects of honokiol derivatives, derivatizations were performed using tetrahydrohonokiol as a scaffold. The derivatizations comprised the introduction of functional groups, e.g., nitro and amino groups, as well as alkylation. This way, 18 derivatives, of which 13 were previously undescribed compounds, were evaluated against CCRF-CEM leukemia cells, U251 glioblastoma and HCT-116 colon cancer cells. The results revealed no significant cytotoxic effects in any of the three tested cell lines at a test concentration of 10 µM.

  3. Synthesis of Tetrahydrohonokiol Derivates and Their Evaluation for Cytotoxic Activity against CCRF-CEM Leukemia, U251 Glioblastoma and HCT-116 Colon Cancer Cells

    Directory of Open Access Journals (Sweden)

    Marketa Bernaskova

    2014-01-01

    Full Text Available Biphenyl neolignans such as honokiol and magnolol, which are the major active constituents of the Asian medicinal plant Magnolia officinalis, are known to exert a multitude of pharmacological and biological activities. Among these, cytotoxic and tumor growth inhibitory activity against various tumour cell lines are well-documented. To further elucidate the cytotoxic effects of honokiol derivatives, derivatizations were performed using tetrahydrohonokiol as a scaffold. The derivatizations comprised the introduction of functional groups, e.g., nitro and amino groups, as well as alkylation. This way, 18 derivatives, of which 13 were previously undescribed compounds, were evaluated against CCRF-CEM leukemia cells, U251 glioblastoma and HCT-116 colon cancer cells. The results revealed no significant cytotoxic effects in any of the three tested cell lines at a test concentration of 10 µM.

  4. Preparation of functionalized nano-graphene oxide particles and their target imaging role in glioma U251 cells%功能化纳米氧化石墨烯微粒的制备及对脑胶质瘤U251细胞的靶向显像作用

    Institute of Scientific and Technical Information of China (English)

    邓跃飞; 李忠军; 庞家栋; 张黎明

    2013-01-01

    Objective To prepare the functionalized nano-graphene oxide (nano-GO) particles,and study their targeted fluorescence imaging effects on glioma U251 cells under near infrared (NIR)irradiation.Methods Single-layer nano-GO particles were obtained after ultrasonic oscillation,and then connected with transferrin (Tf) and fluorescein isothiocyanate (FITC) through poly-L-lysine-G3 to prepare functionalized nano-GO-Tf-FITC particles.Sample morphology was observed and the particle sizes were measured under certain transmission electron microscope (TEM).Glioma U251 cells were employed and divided into targeted experimental group (adding functionalized nano-GO-Tf-FITC particles),parallel control group (adding anti-CD71-FITC reagent) and non-targeted experimental group (adding nano-GO-FITC particles).Fluorescence imaging of these groups was determined by fluorescence microscopy.Results Single-layer particles with a range of 20-100 nm were observed under high TEM,and the functionalized nano-GO-Tf-FITC particles were distributed in a pattern of single layer with a diameter smaller than 100 nm.Yellow green color was monitored in the targeted experimental group and parallel control group,and no imaging was monitored in the non-targeted experimental group because of no transferring integration.Conclusion Functionalized nano-GO-Tf-FITC particles are successfully prepared,and show marked targeted imaging effects on glioma U251 cells.%目的 制备功能化纳米氧化石墨烯(nano-GO-Tf-FITC)微粒,并研究其在近红外线(NIR)照射下对脑胶质瘤U251细胞的靶向荧光显像作用. 方法 将氧化石墨烯(GO)超声振荡制得纳米单层GO(nano-GO)微粒,以聚赖氨酸叠氮基团(poly-L-lysine-G3)连接靶向分子转铁蛋白(Tf)和荧光分子异硫氰酸荧光素(FITC),制备出功能化nano-GO-Tf-FITC微粒,应用透射电镜在一定倍数下观察并拍摄样品形貌,测定样品粒径.将培养的脑胶质瘤U251细胞分成3组,即靶向实验组(加入nano

  5. Noradrenaline increases intracellular glutathione in human astrocytoma U-251 MG cells by inducing glutamate-cysteine ligase protein via β3-adrenoceptor stimulation.

    Science.gov (United States)

    Yoshioka, Yasuhiro; Kadoi, Hisatsugu; Yamamuro, Akiko; Ishimaru, Yuki; Maeda, Sadaaki

    2016-02-05

    Glutathione (GSH) plays a critical role in protecting cells from oxidative damage. Since neurons rely on the supply of GSH from astrocytes to maintain optimal intracellular GSH concentrations, the GSH concentration of astrocytes is important for the survival of neighboring neurons against oxidative stress. The neurotransmitter noradrenaline is known to modulate the functions of astrocytes and has been suggested to have neuroprotective properties in neurodegenerative diseases. To elucidate the mechanisms underlying the neuroprotective properties of noradrenaline, in this study, we investigated the effect of noradrenaline on the concentrations of intracellular GSH in human U-251 malignant glioma (MG; astrocytoma) cells. Treatment of the cells with noradrenaline for 24h concentration-dependently increased their intracellular GSH concentration. This increase was inhibited by a non-selective β-adrenoceptor antagonist propranolol and by a selective β3-adrenoceptor antagonist SR59230A, but not by a non-selective α-adrenoceptor antagonist phenoxybenzamine, or by a selective β1-adrenoceptor antagonist atenolol or by a selective β2-adrenoceptor antagonist butoxamine. In addition, the selective β3-adrenoceptor agonist CL316243 increased the intracellular GSH in U-251 MG cells. Treatment of the cells with noradrenaline (10μM) for 24h increased the protein level of the catalytic subunit of glutamate-cysteine ligase (GCLc), the rate-limiting enzyme of GSH synthesis; and this increase was inhibited by SR59230A. These results thus suggest that noradrenaline increased the GSH concentration in astrocytes by inducing GCLc protein in them via β3-adrenoceptor stimulation.

  6. Elevation of Ser9 phosphorylation of GSK3β is required for HERV-W env-mediated BDNF signaling in human U251 cells.

    Science.gov (United States)

    Qin, Chengchen; Li, Shan; Yan, Qiujin; Wang, Xiuling; Chen, Yatang; Zhou, Ping; Lu, Mengxin; Zhu, Fan

    2016-08-03

    Human endogenous retrovirus W family (HERV-W) envelope (env) is known to be associated with neurological and psychiatric disorders, such as multiple sclerosis and schizophrenia. Previous studies showed that overexpression of HERV-W env could induce brain-derived neurotrophic factor (BDNF) gene expression. In human and rat cells, BDNF-mediated signal transduction might be modulated by glycogen synthase kinase 3β (GSK3β). Both BDNF and GSK3β are schizophrenia-related genes. In this paper, we investigated whether GSK3β was involved in the HERV-W env-induced expression of BDNF. We found that HERV-W env increased phosphorylation of GSK3β at Ser9 (p-GSK3β (Ser9)) and the ratio of p-GSK3β (Ser9) to total GSK3β (pW env led to a 36.2% reduction in GSK3β activity compared to control (pW env might activate the GSK3β signaling pathway in U251 cells. Further, knockdown of GSK3β reduced the expression of total GSK3β, p-GSK3β (Ser9), and the ratio of p-GSK3β (Ser9) to total GSK3β by 28.6%, 50.4%, and 30.2%, respectively (pW env-induced BDNF expression, and will hopefully improve our understanding of the role of HERV-W env in neurological and psychiatric diseases (schizophrenia, etc).

  7. Silver nanoparticles outperform gold nanoparticles in radiosensitizing U251 cells in vitro and in an intracranial mouse model of glioma

    Science.gov (United States)

    Liu, Peidang; Jin, Haizhen; Guo, Zhirui; Ma, Jun; Zhao, Jing; Li, Dongdong; Wu, Hao; Gu, Ning

    2016-01-01

    Radiotherapy performs an important function in the treatment of cancer, but resistance of tumor cells to radiation still remains a serious concern. More research on more effective radiosensitizers is urgently needed to overcome such resistance and thereby improve the treatment outcome. The goal of this study was to evaluate and compare the radiosensitizing efficacies of gold nanoparticles (AuNPs) and silver nanoparticles (AgNPs) on glioma at clinically relevant megavoltage energies. Both AuNPs and AgNPs potentiated the in vitro and in vivo antiglioma effects of radiation. AgNPs showed more powerful radiosensitizing ability than AuNPs at the same mass and molar concentrations, leading to a higher rate of apoptotic cell death. Furthermore, the combination of AgNPs with radiation significantly increased the levels of autophagy as compared with AuNPs plus radiation. These findings suggest the potential application of AgNPs as a highly effective nano-radiosensitizer for the treatment of glioma. PMID:27757033

  8. U251胶质瘤细胞系中脑肿瘤干细胞的分离、培养及鉴定%Isolation,Culture and Identification of Brain Tumor Stem Cellswithin U251 Glioma Cell Line In Vitro

    Institute of Scientific and Technical Information of China (English)

    陈成; 芦明; 李茗初; 方加胜

    2012-01-01

      Objective This study was to isolate, culture and identificate brain tumor stem cel s from U251 Gliome cel line in vitro and observe their growth pattern.To establish a fundation for further reseach of brain tumor stem cel . Methods U251cel s were seeded in serum-free DMEM-F12 medium supplemented with B27, EGF and bFGF in 6-wel plates, after U251 brain tumor spheres formed, they were dissociated and passaged in fresh medium periodical y. U251 brain tumor spheres and the single cel s of them were induced to differentiate in the medium with 10%FBS supplemented. U251cel s cultivate in serum-supplemented medium and serum-free medium alternately. At last we performed immunocytochemistry of U251 brain tumor spheres for CD133 and Nestin. Results Some U251 glioma cel have the capacity to self-renew, proliferate and generate free-floating neurosphere-like brain tumor spheres in serum-free medium in vitro. U251 glioma spheres and the single cel s of them can be induced to differentiate and adherent to the bottom of the culture plates. The growing patterns of U251 glioma cel line can be converted by changing the culture mediums. The brain tumor stem cel are CD133+Nestin+cel s. Conclusion The U251 glioma cel line contain brain tumor stem cel s which can be isolated, proliferated and differentiated in vitro. The research of brain tumor stem cel s may provide a new platform for brain tumor study.%  目的本研究旨在从U251胶质瘤细胞系中分离、培养和鉴定脑肿瘤干细胞,观察其的生长特征,为脑肿瘤干细胞的进一步研究打下基础。方法应用简化的无血清培养基和悬浮培养法培养U251细胞,并将获得的脑肿瘤干细胞接种于含血清培养基中观察其分化;交替用含血清培基和无血清培基培养U251细胞,观察其生长特性;用免疫荧光法检测脑肿瘤干细胞中CD133和Nestin的表达。结果 U251细胞接种至无血清培养基后,部分细胞能够存活并增殖为悬浮

  9. EGCG诱导人胶质瘤细胞U251凋亡及对survvin表达的影响%Induction of Apoptosis in Glioblastoma Cell line U251 of Epigallocatechin-3-gallate and its Influence on the Expressions of Surviv in Protein

    Institute of Scientific and Technical Information of China (English)

    赵志远; 谢瑞; 王宇

    2012-01-01

    目的:观察表没食子儿茶素没食子酸酯(EGCG)诱导人胶质瘤细胞(U251)凋亡的生物学效应及对survivin蛋白表达的影响.方法:采用MTT法检测不同浓度EGCG对U251细胞增殖抑制作用;吖啶橙/溴化乙啶(AO/EB)荧光双染法观察各组细胞凋亡形态,计算凋亡率;Wester Blot法检测不同剂量EGCG处理48 h对survivin蛋白表达的影响.结果:EGCG显著抑制U251细胞生长,呈浓度依赖性;EGCG可以诱导U251细胞凋亡,细胞凋亡率随着药物浓度的增加而逐渐增加.Wester Blot结果显示EGCG抑制Survivin蛋白的表达.结论:EGCG具有诱导U251细胞凋亡的作用,其机制可能与抑制Survivin蛋白的表达相关.

  10. Research on biological functions of U251 astroglioma cells infected with human herpesvirus type 6(HHV-6)%人类疱疹病毒6型感染U251细胞及其生物学功能的研究

    Institute of Scientific and Technical Information of China (English)

    郭一迪; 姚堃; 周锋; 李凌云; 茌静; 刘根焰; 陈云

    2010-01-01

    目的:研究人类疱疹病毒6型(HHV-6)感染人星形胶质瘤细胞U251,及感染后对其生物学功能的影响.方法:HHV-6感染U251细胞建立HHV-6体外感染模型,倒置显微镜观察细胞病变.PCR法检测HHV-6 u22基因.间接免疫荧光(IFA)检测HHV-6即刻早期蛋白(IEI)和晚期蛋白(gB)的表达.MTT法检测U251感染HHV-6后细胞增殖的改变.流式细胞术(FCM)检测U251细胞周期改变.结果:在感染3天后U251出现典型细胞病变,细胞肿胀增大数倍,透亮,呈多形性.PCR检测到HHV-6u22基因.IFA检测到HHV-6 IE1蛋白和异B蛋白的表达.MTT法显示HHV-6能增强U251细胞的增殖能力.FCM检测表明,HHV-6感染后U251细胞周期发生改变,感染组和对照组相比,前者G1期的细胞减少,S期和G2期细胞增多.结论:HHV-6能感染U251细胞引起细胞病变.促进细胞的增殖.使细胞周期发生改变.本研究结果提示人类疱疹病毒6型可能参与人神经胶质瘤的发生、发展,对其机制尚不清楚.

  11. Study on mechanism of temozolomide-resistant human glioma cell line U251/TR changed by temozolomide in vitro%替莫唑胺改变人胶质瘤细胞系U251耐药机制的体外研究

    Institute of Scientific and Technical Information of China (English)

    潘强; 杨学军; 高松; 纪延伟; 张文高; 李瑜; 王维; 董雪涛; 王华民

    2009-01-01

    目的 建立替莫唑胺耐药人胶质瘤细胞系,探讨其耐药性变化规律及耐药机制,以期为临床优化药物化疗方案提供理论依据.方法 采用分步诱导法使人胶质瘤细胞系U251对替莫唑胺耐药,磺酰罗丹明B比色法检测细胞耐药指数和存活率;Western blotting法检测O6-甲基鸟嘌呤-DNA甲基转移酶(MGMT)表达水平,以及倍增替莫唑胺终浓度后MGMT表达水平.结果 成功建立替莫唑胺耐药U251/TR细胞,在替莫唑胺初始诱导剂量0.25μg/ml、终浓度16.00μg/ml培养液中,U251/TR细胞半数抑制浓度为(220.87±2.34)μmol/L,约为U251细胞[(33.12±1.52)μmol/L]的7倍(t=-116.542,P=0.000),其耐药指数约为7;U251/TR细胞MGMT表达水平为(1.47±0.30),较U251细胞(0.19±0.03)明显升高(t=-20.230,P=0.000).与溶媒对照组比较,经倍增替莫唑胺终浓度诱导的U251/TR细胞仍呈现增殖抑制现象,以体外培养第3天时最为明显(P=0.000);MGMT表达水平相应降低(均P=0.000),呈现自身克服耐药现象.结论 采用分步诱导法可于体外成功建立替莫唑胺耐药人胶质瘤细胞系.MGMT表达水平升高是导致U251/TR细胞对替莫唑胺耐药的主要机制,替莫唑胺可以通过自身消耗MGMT而改变U251/TR细胞的耐药特性,发挥抗耐药作用.

  12. Study on mechanism of thalidomide combined with temozolomide to suppress proliferation of U251 glioma cell in vitro%沙利度胺联合替莫唑胺杀伤U251胶质瘤细胞机制的体外研究

    Institute of Scientific and Technical Information of China (English)

    高松; 潘强; 曾峥; 孙健; 杨学军

    2010-01-01

    目的 对沙利度胺联合替莫唑胺杀伤U251胶质瘤细胞的机制进行体外研究,为制订沙利度胺与替莫唑胺联合化疗方案提供理论依据.方法 经体外培养的人胶质瘤细胞系U251分别接受替莫唑胺(100 μmol/L)、沙利度胺(100 μg/L)、替莫唑胺与沙利度胺联合治疗,噻唑监(MTT)法检测不同抗肿瘤药物处理组肿瘤细胞增殖活性;流式细胞术分析细胞增殖周期;检测经吖啶橙标记的酸性囊性细胞器数目;原位末端标记(TUNEL)法观察肿瘤细胞凋亡情况;Western blotting法榆测肿瘤自噬及凋亡相关蛋白表达变化.结果 与替莫唑胺和沙利度胺单药治疗相比,替莫唑胺与沙利度胺联合治疗对U251细胞生长的抑制更为明显(均P=0.000).且可诱导肿瘤细胞周期阻滞于G0~G1期,以及发生凋亡和自噬.两药联合治疗后,U251细胞微管相关蛋白1轻链3和Caspase-3表达水平高于替莫唑胺组和沙利度胺组(均P=0.000).结论 沙利度胺联合替莫唑胺治疗U251细胞可以上调自噬及凋亡相关基因表达水平.同时诱导凋亡及自噬性死亡,从而达到对U251胶质瘤细胞的杀伤作用.

  13. Effects of Autocrine Motility Factor (AMF) on the Migration and Invasion of Glioblastoma U251 Cells and Their Mechanism%自分泌运动因子AMF对人胶质母细胞瘤U251细胞迁移、侵袭的影响及相关机制研究

    Institute of Scientific and Technical Information of China (English)

    李阳; 汤宁; 刘哲宇; 孙铮

    2016-01-01

    为了探讨自分泌运动因子(autocrine motility factor,AMF)对人胶质母细胞瘤U251细胞迁移、侵袭影响及其相关分子机制,该实验采用了RT-PCR及免疫印迹法检测RNA干扰AMF后U251细胞中AMF的表达变化;细胞划痕实验、Transwell实验分别观察了AMF干扰前后U251细胞迁移、侵袭能力的变化;免疫印记检测AMF干扰前后细胞中总Akt、p-Akt、Sox2、基质金属蛋白酶-2(matrix metalloprotein-2,MMP-2)及MMP-9蛋白水平的变化.研究结果表明,AMF成功干扰后U251细胞的迁移和侵袭能力受到抑制,p-Akt、Sox2、MMP-2和MMP-9蛋白表达水平降低.该研究表明,AMF敲低可以通过下调PI3K/Ak信号通路活性及Sox2、MMP-2和MMP-9蛋白水平,抑制人胶质母细胞瘤U251细胞迁移和侵袭.

  14. Effect of Notch -1 gene uprugulation on AKT -mTOR signal of U251 cell%上调 Notch-1基因对 U215细胞 AKT -mTOR 通路的影响

    Institute of Scientific and Technical Information of China (English)

    楚可新; 戴明明; 林勤; 赵能江

    2016-01-01

    Objective:To investigate the effect of Notch -1 gene up -regulation on biological hehaviors of U215 cell and explore its effects on AKT -mTOR signal.Methods:U251 cells were infected with over -expression NICD or control lentivirus,the mRNA and protein expression of Notch -1 gene were examined with RT -PCR and Western -Blot,the cell proliferation was assayed with MTT,cell cycle was determined by flow cytometry,the effects of Notch -1 gene on U251 cell invasion were studied using matrigel coated Transwell chambers,the effects of Notch -1 up -gula-tion on AKT,mTOR,P70S6K and 4Ebp -1 protein expression were also analyzed.Results:Compared with the un-treated and empty group,after 72h of infection,the protein and mRNA expression of Notch -1 increased(P <0.05). It was found that up -regulation of Notch -1 promoted U251 cell growth,invasion and S -phase cells were increased (P <0.05).Up -regulation of Notch -1 promoted Cyclin D1,CDK -4 protein expression,and p -AKT and p -mTOR also increased in Notch -1 up -regulated U251 cells.Conclusion:Up -regulation Notch -1 promotes U251 glioma cell proliferation and invasion,the mechanism was partly through regulating AKT -mTOR signaling.%目的:观察上调 Notch -1基因对人胶质瘤 U251细胞生学物行为及 AKT -mTOR 信号通路的影响。方法:采用 pNL -NICD 慢病毒感染 U251细胞,以 RT -PCR 和 Western -Blot 检测 Notch -1基因 mRNA 和蛋白的表达,以 MTT 检测细胞增殖能力,流式细胞术检测细胞周期变化,Transwell 实验检测细胞侵袭能力,同时检测 Notch -1上调对 AKT、mTOR、P70S6K、4Ebp -1蛋白的影响。结果:与对照组比较,NICD 慢病毒转染72h后,Notch -1基因 mRNA 和蛋白表达明显增高(P <0.01);Notch -1上调明显促进 U251细胞增殖、侵袭、促进细胞进入 S 期,增加周期蛋白 Cyclin D1、CDK -4的表达,促进 AKT、mTOR 蛋白磷酸化。结论:上调 Notch -1基因促进 U251

  15. Effects of VE-statin/Egfl7 gene silencing on gene expression profiles of malignant glioma cell U251%VE-statin/Egfl7基因沉默对恶性胶质瘤细胞U251基因表达谱的影响

    Institute of Scientific and Technical Information of China (English)

    黄纯海; 田志; 万一; 张晶晶

    2013-01-01

    目的 探讨VE-statin/Egfl7基因在恶性胶质瘤中表达的分子调控机制.方法 用小RNA干扰技术沉默VE-statin/Egfl7基因在人恶性胶质瘤U251细胞中的表达,然后用基因表达谱芯片研究VE-statin/Egfl7基因沉默前后该细胞基因表达谱的变化,进行生物信息学分析.并选取两条差异表达基因用实时荧光定量PCR进行验证.结果 通过RNA干扰技术明显抑制了VE-statin/Egfl7基因在U251细胞中的表达.基因表达芯片检测结果发现与对照组相比,实验组下调基因有141条,包括未知功能基因7条,已知功能基因134条;上调的基因有130条,包括未知功能基因3条,已知功能基因127条.通过生物信息学分析发现这些基因主要与细胞增殖分化、凋亡及细胞外基质黏附等生物学功能密切相关,涉及的主要信号通路包括表皮生长因子受体ERBB家族信号、细胞存活信号及整合素αvβ3信号.结论 VE-statin/Egfl7在恶性胶质瘤中的分子调控机制可能通过PBK/Akt和Ras/MAPK两条信号转导通路实现,为进一步研究VE-statin/Egfl7的功能和分子机制提供了新的线索.

  16. 14-3-3和CLIC4蛋白在U251细胞自噬中的相互作用%The interaction of 14-3-3 and CLIC4 proteins in the autophagy of U251 cells

    Institute of Scientific and Technical Information of China (English)

    袁兆新; 金笛; 张宏宇

    2015-01-01

    目的 通过饥饿诱导神经胶质瘤U251细胞发生自噬,探讨细胞CLIC4和14-3-3蛋白在饥饿条件下诱导自噬过程中的相互作用.方法 通过Hoechst、14-3-3 epsilon、CLIC4染色于共聚焦显微镜下观察抑制CLIC4表达对于饥饿条件下,14-3-3 epsilon蛋白与CLIC4共定位的影响.通过Western Blot技术检测Beclin 1及14-3-3蛋白表达.免疫共沉淀技术检测14-3-3 epsilon蛋白与CLIC4蛋白的结合水平.结果 共聚焦显微镜观察14-3-3 epsilon和CLIC4荧光染色结果显示,饥饿条件下,14-3-3 epsilon蛋白与CLIC4共定位显著增加,并广泛分布于胞浆及细胞核中.同时Westem Blot结果表明抑制CLIC4表达能够引起14-3-3蛋白以及自噬相关蛋白Beclin1表达增加.饥饿条件下,14-3-3 epsilon蛋白与CLIC4共沉淀增强,而抑制CLIC4表达能够降低两者结合水平.结论 14-3-3epsilon蛋白与CLIC4的相互作用由于RNA干扰而减弱,促进了14-3-3蛋白水平上调,进而增强了14-3-3蛋白对Beclin1信号通路的调节,引起Beclin1表达增加,进一步激活饥饿条件下U251细胞自噬过程.

  17. The Parvalbumin/Somatostatin Ratio Is Increased in Pten Mutant Mice and by Human PTEN ASD Alleles

    Directory of Open Access Journals (Sweden)

    Daniel Vogt

    2015-05-01

    Full Text Available Mutations in the phosphatase PTEN are strongly implicated in autism spectrum disorder (ASD. Here, we investigate the function of Pten in cortical GABAergic neurons using conditional mutagenesis in mice. Loss of Pten results in a preferential loss of SST+ interneurons, which increases the ratio of parvalbumin/somatostatin (PV/SST interneurons, ectopic PV+ projections in layer I, and inhibition onto glutamatergic cortical neurons. Pten mutant mice exhibit deficits in social behavior and changes in electroencephalogram (EEG power. Using medial ganglionic eminence (MGE transplantation, we test for cell-autonomous functional differences between human PTEN wild-type (WT and ASD alleles. The PTEN ASD alleles are hypomorphic in regulating cell size and the PV/SST ratio in comparison to WT PTEN. This MGE transplantation/complementation assay is efficient and is generally applicable for functional testing of ASD alleles in vivo.

  18. Cisplatin Resistance Inducing and Autophagy in Glioma Cell Line U251%顺铂耐受胶质瘤细胞株诱导和细胞自噬的观察

    Institute of Scientific and Technical Information of China (English)

    付军; 陈芙蓉; 陈忠平

    2007-01-01

    背景与目的:明确胶质瘤耐药相关分子机制,有助于寻找新的治疗对策.我们将诱导对顺铂耐药的脑胶质瘤细胞株,探讨细胞自噬和胶质瘤细胞顺铂耐受的关系.方法:应用人胶质瘤细胞株U251,采用顺铂剂量梯度爬升筛选方法,诱导耐药胶质瘤细胞株;用MTT法测定该耐药细胞对顺铂的半数抑制浓度(IC50);电镜和GFP-LC3荧光染色检测细胞内自噬体;AnnexinV-FITC染色检测细胞凋亡;Western blot检测自噬相关蛋白LC3、Beclin 1以及凋亡分子Caspase-3水平.结果:我们诱导获得的耐药胶质瘤细胞株U251/CP2对顺铂半数抑制浓度(IC50)较亲代U251增加了62.7倍(分别是1.2±0.4 ìg/ml和76.5±22.5 μg/ml).电镜和GFP-LC3荧光染色观察表明胶质瘤细胞呈现典型的自噬特征,表现为电镜下广泛的自噬性空泡的出现和GFP-LC3斑点状分布,且能够被自噬抑制剂3-MA和ERK抑制剂PD98059抑制.凋亡检测表明,经顺铂处理后,U251/CP2较U251凋亡率低,3-MA和PD98059能够显著增强顺铂对U251/CP2的凋亡诱导作用.Western blot检测表明,U251/CP2较U251具有显著上调的LC3和Beclin 1水平,而Caspase-3水平较低.结论:U251胶质瘤细胞能够通过自噬作用保护细胞免受化疗药物顺铂的杀伤,从而免于发生细胞凋亡.

  19. Effect of methylation levels of GDNF gene promoterⅠregion on its transcription in glioma U251 cells%胶质瘤细胞GDNF基因启动子Ⅰ区甲基化水平对其基因转录的影响

    Institute of Scientific and Technical Information of China (English)

    续继军; 孟铸; 李志鹏; 陈欣; 任庆先; 秦汉

    2015-01-01

    目的:探讨胶质瘤细胞胶质细胞原性神经营养因子(GDNF)基因启动子Ⅰ区甲基化水平对其基因转录的影响。方法体外培养胶质瘤U251细胞,加入不同浓度5-氮杂胞苷(浓度分别为1、5、10和20μmol/L)干预,以加入PBS为对照。采用重亚硫酸盐测序法测定GDNF基因启动子Ⅰ区甲基化水平,RT-PCR检测GDNF mRNA的表达。结果与PBS组相比,1μmol/L 5-氮杂胞苷对GDNF基因启动子Ⅰ区甲基化水平无显著影响(P>0.05),5、10和20μmol/L 5-氮杂胞苷均显著降低其甲基化水平(P0.05),5μmol/L 5-氮杂胞苷显著增加其表达水平(P0.05). Conclusion The demethylation of GDNF gene promoterⅠregion, which is produced by 5-aza-CR, may influence the expression of GDNF in U251 cell.

  20. Mind Bomb-2 promotes U251 proliferation by regulating nuclear factor kappa B signaling pathways%Mind Bomb-2基因通过调控核因子κB信号通路促进 U251增殖的实验研究

    Institute of Scientific and Technical Information of China (English)

    张伯阳; 许重远

    2016-01-01

    Objective To study effects of Mind Bomb -2 ( MIB2 ) gene expression ’ s promotion on proliferation of U 251.Methods The expression of MIB2 protein in astrocyte and US251 was detected by Western blot.U251, U251 transduction with FLAG ( A 20 base coded marker protein ) plasmid and U251transfection with MIB2 -FLAG plasmid were divided into blank group , control group and test group correspondingly.The relative content of MIB 2 in three groups was detected by Western blotting .The MIB2 -FLAG plasmid was transfected to U251 cells.The real -time quantitative PCR was used to detect MIB 2 mRNA expression in U251.The expression of MIB2, I kappa B ( IkB) and nuclear factor kappa B ( NF-κB) was detected by Western blotting after transfection.MTT experiment was used to detect the proliferation of U251 cells after transfection.Results The relative content of MIB 2 in U251 cells increased by ( 17.04 ±2.91 ) compared with astrocytes.MIB2 mRNA in test group increased by ( 20.02 ±2.11 ) compared with control group.The expression of MIB 2 and NF-κB proteins in test group increased by ( 6.33 ±0.32 ) and ( 5.21 ±0.21 ) compared with control group, the expression of IkB in test group was attenuated by (0.43 ±0.04 ) compared with control group .Com-pared with both blank and control group , test group grew significantly ( P<0.001 ) .Conclusion MIB2 promoted U251 proliferation by regulating NF-κB signaling pathways.%目的:研究Mind Bomb-2(MIB2)的表达对脑胶质瘤细胞U251增殖的影响。方法用蛋白质印迹法检测正常星形胶质细胞和胶质瘤细胞U251和MIB2蛋白的表达情况。将U251细胞、转染FLAG (一种20个碱基编码的标记蛋白)质粒的U251细胞和转染MIB2-FLAG质粒的U251细胞对应分为空白组、对照组和实验组。以蛋白质印迹法检测上述3组中MIB2的相对含量;采用实时定量PCR技术检测MIB2 mRNA在3组U251细胞中的表达情况;以蛋白质印迹法检测转染后U251细胞中MIB2

  1. A Novel PTEN/Mutant p53/c-Myc/Bcl-XL Axis Mediates Context-Dependent Oncogenic Effects of PTEN with Implications for Cancer Prognosis and Therapy

    Directory of Open Access Journals (Sweden)

    Xiaoping Huang

    2013-08-01

    Full Text Available Phosphatase and tensin homolog located on chromosome 10 (PTEN is one of the most frequently mutated tumor suppressors in human cancer including in glioblastoma. Here, we show that PTEN exerts unconventional oncogenic effects in glioblastoma through a novel PTEN/mutant p53/c-Myc/Bcl-XL molecular and functional axis. Using a wide array of molecular, genetic, and functional approaches, we demonstrate that PTEN enhances a transcriptional complex containing gain-of-function mutant p53, CBP, and NFY in human glioblastoma cells and tumor tissues. The mutant p53/CBP/NFY complex transcriptionally activates the oncogenes c-Myc and Bcl-XL, leading to increased cell proliferation, survival, invasion, and clonogenicity. Disruption of the mutant p53/c-Myc/Bcl-XL axis or mutant p53/CBP/NFY complex reverses the transcriptional and oncogenic effects of PTEN and unmasks its tumor-suppressive function. Consistent with these data, we find that PTEN expression is associated with worse patient survival than PTEN loss in tumors harboring mutant p53 and that a small molecule modulator of p53 exerts greater antitumor effects in PTEN-expressing cancer cells. Altogether, our study describes a new signaling pathway that mediates context-dependent oncogenic/tumor-suppressive role of PTEN. The data also indicate that the combined mutational status of PTEN and p53 influences cancer prognosis and anticancer therapies that target PTEN and p53.

  2. Quantitative Proteomic Profiling of Tachyplesin I Targets in U251 Gliomaspheres

    Directory of Open Access Journals (Sweden)

    Xuan Li

    2017-01-01

    Full Text Available Tachyplesin I is a cationic peptide isolated from hemocytes of the horseshoe crab and its anti-tumor activity has been demonstrated in several tumor cells. However, there is limited information providing the global effects and mechanisms of tachyplesin I on glioblastoma multiforme (GBM. Here, by using two complementary proteomic strategies (2D-DIGE and dimethyl isotope labeling-based shotgun proteomics, we explored the effect of tachyplesin I on the proteome of gliomaspheres, a three-dimensional growth model formed by a GBM cell line U251. In total, the expression levels of 192 proteins were found to be significantly altered by tachyplesin I treatment. Gene ontology (GO analysis revealed that many of them were cytoskeleton proteins and lysosomal acid hydrolases, and the mostly altered biological process was related to cellular metabolism, especially glycolysis. Moreover, we built protein–protein interaction network of these proteins and suggested the important role of DNA topoisomerase 2-alpha (TOP2A in the signal-transduction cascade of tachyplesin I. In conclusion, we propose that tachyplesin I might down-regulate cathepsins in lysosomes and up-regulate TOP2A to inhibit migration and promote apoptosis in glioma, thus contribute to its anti-tumor function. Our results suggest tachyplesin I is a potential candidate for treatment of glioma.

  3. The influence of the combined treatment with Vadimezan (ASA404 and taxol on the growth of U251 glioblastoma xenografts

    Directory of Open Access Journals (Sweden)

    Milanović Dušan

    2012-06-01

    Full Text Available Abstract Background One of the most important biological characteristics of Glioblastoma multiforme (GBM is high vascular density. Vadimezan (ASA404, DMXAA belongs to the class of small molecule vascular disrupting agents (VDA that cause disruption of established tumor vessels and subsequent tumor hemorrhagic necrosis. Its selective antivascular effect is mediated by intratumoral induction of several cytokines including tumor necrosis factor-α (TNF-α, granulocyte-colony-stimulating factor (G-CSF, interleukin 6 (IL-6 and macrophage inflammatory protein 1α (MIP-1α. Preclinical studies have demonstrated that ASA404 acts synergistically with taxanes. In this study, we investigated if treatment of mice bearing U251 human glioblastoma xenografts with ASA404 and taxol may be synergistic. Therapy response was evaluated by measuring changes in tumor size and metabolic activity using 18F-FDG PET (Fluorodeoxyglucose - positron emision tomography imaging. Methods U251 cells were inoculated s.c. in the right hind limb of NMRI-Foxn1nu athymic female nude mice. Animals were randomly assigned into 4 groups (7–9 animals/group for treatment: control, taxol, ASA404, and ASA404 plus taxol. The animals received either a single dose of taxol (10 mg/kg, ASA404 (27.5 mg/kg, or taxol (10 mg/kg plus ASA404 (27.5 mg/kg administered i.p.; ASA404 was administred 24 h after the treatment with taxol. 4 and 24 h after treatment with ASA404 (28 and 48 h hours after treatment with taxol 18 F-FDG PET scans were performed. Results The treatment with taxol did not affect the tumor growth in comparison to untreated controls. The treatment of animals with single dose ASA404 alone or in combination with taxol caused a significant delay in tumor growth. The combined treatment did not decrease the growth of the xenografts significantly more than ASA404 alone, but early changes in tumor 18 F-FDG uptake preceded subsequent growth inhibition. The tumor weights

  4. Fast Neutron Induced Autophagy Leads To Necrosis In Glioblastoma Multiforme Cells

    Science.gov (United States)

    Yasui, Linda; Gladden, Samantha; Andorf, Christine; Kroc, Thomas

    2011-06-01

    Fast neutrons are highly effective at killing glioblastoma multiforme (GBM), U87 and U251 cells. The mode of cell death was investigated using transmission electron microscopy (TEM) to identify the fraction of irradiated U87 or U251 cells having morphological features of autophagy and/or necrosis. U87 or U251 cells were irradiated with 2 Gy fast neturons or 10 Gy γ rays. A majority of U87 and U251 cells exhibit features of cell death with autophagy after irradiation with either 10 Gy γ rays or 2 Gy fast neutrons. Very few γ irradiated cells had features of necrosis (U87 or U251 cell samples processed for TEM 1 day after 10 Gy γ irradiation). In contrast, a significant increase was observed in necrotic U87 and U251 cells irradiated with fast neutrons. These results show a greater percentage of cells exhibit morphological evidence of necrosis induced by a lower dose of fast neutron irradiation compared to γ irradiation. Also, the evidence of necrosis in fast neutron irradiated U87 and U251 cells occurs in a background of autophagy. Since autophagy is observed before necrosis, autophagy may play a role in signaling programmed necrosis in fast neutron irradiated U87 and U251 cells.

  5. Cell-Type Specific Roles for PTEN in Establishing a Functional Retinal Architecture

    Science.gov (United States)

    Cantrup, Robert; Dixit, Rajiv; Palmesino, Elena; Bonfield, Stephan; Shaker, Tarek; Tachibana, Nobuhiko; Zinyk, Dawn; Dalesman, Sarah; Yamakawa, Kazuhiro; Stell, William K.; Wong, Rachel O.; Reese, Benjamin E.; Kania, Artur; Sauvé, Yves; Schuurmans, Carol

    2012-01-01

    Background The retina has a unique three-dimensional architecture, the precise organization of which allows for complete sampling of the visual field. Along the radial or apicobasal axis, retinal neurons and their dendritic and axonal arbors are segregated into layers, while perpendicular to this axis, in the tangential plane, four of the six neuronal types form patterned cellular arrays, or mosaics. Currently, the molecular cues that control retinal cell positioning are not well-understood, especially those that operate in the tangential plane. Here we investigated the role of the PTEN phosphatase in establishing a functional retinal architecture. Methodology/Principal Findings In the developing retina, PTEN was localized preferentially to ganglion, amacrine and horizontal cells, whose somata are distributed in mosaic patterns in the tangential plane. Generation of a retina-specific Pten knock-out resulted in retinal ganglion, amacrine and horizontal cell hypertrophy, and expansion of the inner plexiform layer. The spacing of Pten mutant mosaic populations was also aberrant, as were the arborization and fasciculation patterns of their processes, displaying cell type-specific defects in the radial and tangential dimensions. Irregular oscillatory potentials were also observed in Pten mutant electroretinograms, indicative of asynchronous amacrine cell firing. Furthermore, while Pten mutant RGC axons targeted appropriate brain regions, optokinetic spatial acuity was reduced in Pten mutant animals. Finally, while some features of the Pten mutant retina appeared similar to those reported in Dscam-mutant mice, PTEN expression and activity were normal in the absence of Dscam. Conclusions/Significance We conclude that Pten regulates somal positioning and neurite arborization patterns of a subset of retinal cells that form mosaics, likely functioning independently of Dscam, at least during the embryonic period. Our findings thus reveal an unexpected level of cellular

  6. Cell-type specific roles for PTEN in establishing a functional retinal architecture.

    Directory of Open Access Journals (Sweden)

    Robert Cantrup

    Full Text Available BACKGROUND: The retina has a unique three-dimensional architecture, the precise organization of which allows for complete sampling of the visual field. Along the radial or apicobasal axis, retinal neurons and their dendritic and axonal arbors are segregated into layers, while perpendicular to this axis, in the tangential plane, four of the six neuronal types form patterned cellular arrays, or mosaics. Currently, the molecular cues that control retinal cell positioning are not well-understood, especially those that operate in the tangential plane. Here we investigated the role of the PTEN phosphatase in establishing a functional retinal architecture. METHODOLOGY/PRINCIPAL FINDINGS: In the developing retina, PTEN was localized preferentially to ganglion, amacrine and horizontal cells, whose somata are distributed in mosaic patterns in the tangential plane. Generation of a retina-specific Pten knock-out resulted in retinal ganglion, amacrine and horizontal cell hypertrophy, and expansion of the inner plexiform layer. The spacing of Pten mutant mosaic populations was also aberrant, as were the arborization and fasciculation patterns of their processes, displaying cell type-specific defects in the radial and tangential dimensions. Irregular oscillatory potentials were also observed in Pten mutant electroretinograms, indicative of asynchronous amacrine cell firing. Furthermore, while Pten mutant RGC axons targeted appropriate brain regions, optokinetic spatial acuity was reduced in Pten mutant animals. Finally, while some features of the Pten mutant retina appeared similar to those reported in Dscam-mutant mice, PTEN expression and activity were normal in the absence of Dscam. CONCLUSIONS/SIGNIFICANCE: We conclude that Pten regulates somal positioning and neurite arborization patterns of a subset of retinal cells that form mosaics, likely functioning independently of Dscam, at least during the embryonic period. Our findings thus reveal an unexpected

  7. MiR-16 modulate temozolomide resistance by regulating BCL-2 in human glioma cells.

    Science.gov (United States)

    Han, Jing; Chen, Qianxue

    2015-01-01

    Temozolomide (TMZ) with radiotherapy is the current standard of care for newly diagnosed glioma. However, glioma patients who are treated with the drug often develop resistance to it and some other drugs. Recently studies have shown that microRNAs (miRNAs) play an important role in drug resistance. In present study, we first examined the sensitivity to temozolomide in six glioma cell lines, and established a resistant variant, U251MG/TR cells from TMZ-sensitive glioma cell line, U251MG. We then performed a comprehensive analysis of miRNA expressions in U251MG/TR and parental cells using cancer microRNA PCR Array. Among the downregulated microRNAs was miR-16, members of miR-15/16 family, whose expression was further validated by qRT-PCR in U251MG/TR and U251MG cells. The selective microRNA, miR-16 mimics or inhibitor was respectively transfected into U251MG/TR cells and AM38 cell. We found that treatment with the mimics of miR-16 greatly decreased the sensitivity of U251MG/TR cells to temozolomide, while sensitivity to these drugs was increased by treatment with the miR-16 inhibitor. In addition, the downregulation of miR-16 in temozolomide-sensitive AM38 cells was concurrent with the upregulation of Bcl-2 protein. Conversely, overexpression of miR-16 in temozolomide-resistant cells inhibited Bcl-2 expression and decreased temozolomide resistance. In conclusion, MiR-16 mediated temozolomide-resistance in glioma cells by modulation of apoptosis via targeting Bcl-2, which suggesting that miR-16 and Bcl-2 would be potential therapeutic targets for glioma therapy.

  8. Conditioned Media from Human Adipose Tissue-Derived Mesenchymal Stem Cells and Umbilical Cord-Derived Mesenchymal Stem Cells Efficiently Induced the Apoptosis and Differentiation in Human Glioma Cell Lines In Vitro

    Directory of Open Access Journals (Sweden)

    Chao Yang

    2014-01-01

    Full Text Available Human mesenchymal stem cells (MSCs have an intrinsic property for homing towards tumor sites and can be used as tumor-tropic vectors for tumor therapy. But very limited studies investigated the antitumor properties of MSCs themselves. In this study we investigated the antiglioma properties of two easily accessible MSCs, namely, human adipose tissue-derived mesenchymal stem cells (ASCs and umbilical cord-derived mesenchymal stem cells (UC-MSCs. We found (1 MSC conditioned media can significantly inhibit the growth of human U251 glioma cell line; (2 MSC conditioned media can significantly induce apoptosis in human U251 cell line; (3 real-time PCR experiments showed significant upregulation of apoptotic genes of both caspase-3 and caspase-9 and significant downregulation of antiapoptotic genes such as survivin and XIAP after MSC conditioned media induction in U 251 cells; (4 furthermore, MSCs conditioned media culture induced rapid and complete differentiation in U251 cells. These results indicate MSCs can efficiently induce both apoptosis and differentiation in U251 human glioma cell line. Whereas UC-MSCs are more efficient for apoptosis induction than ASCs, their capability of differentiation induction is not distinguishable from each other. Our findings suggest MSCs themselves have favorable antitumor characteristics and should be further explored in future glioma therapy.

  9. Cell context-dependent dual effects of EFEMP1 stabilizes subpopulation equilibrium in responding to changes of in vivo growth environment.

    Science.gov (United States)

    Hu, Yuanjie; Ke, Chao; Ru, Ning; Chen, Yumay; Yu, Liping; Siegel, Eric R; Linskey, Mark E; Wang, Ping; Zhou, Yi-Hong

    2015-10-13

    Conflicting functions of EFEMP1 in cancer have been reported. Using two syngeneic glioma cell lines (U251 and U251-NS) carrying two different principal cell subpopulations that express high or low EGFR, and that are able to interconvert via mis-segregation of chromosome 7 (Chr7), we studied EFEMP1's cell-context-dependent functions in regulating subpopulation equilibrium, here defined by the percentage of cells carrying different copies of Chr7. We found that EFEMP1 attenuated levels of EGFR and cellular respiration in high-EGFR-expressing cells, but increased levels of NOTCH1, MMP2, cell invasiveness, and both oxidative phosphorylation and glycolytic respiration in low-EGFR-expressing cells. Consistently, EFEMP1 suppressed intracranial xenograft formation in U251 and promoted its formation in U251-NS. Interestingly, subpopulation equilibria in xenografts of U251-NS without EFEMP1 overexpression were responsive to inoculum size (1, 10 and 100 thousand cells), which may change the tumor-onset environment. It was not observed in xenografts of U251-NS with EFEMP1 overexpression. The anti-EGFR function of EFEMP1 suppressed acceleration of growth of U251-NS, but not the subpopulation equilibrium, when serially passed under a different (serum-containing adherent) culture condition. Overall, the data suggest that the orthotopic environment of the brain tumor supports EFEMP1 in carrying out both its anti-EGFR and pro-invasive/cancer stem cell-transforming functions in the two glioma cell subpopulations during formation of a single tumor, where EFEMP1 stabilizes the subpopulation equilibrium in response to alterations of the growth environment. This finding implies that EFEMP1 may restrain cancer plasticity in coping with ever-changing tumor microenvironments and/or therapeutic-intervention stresses.

  10. Loss of the tumor suppressor Pten promotes proliferation of Drosophila melanogaster cells in vitro and gives rise to continuous cell lines.

    Science.gov (United States)

    Justiniano, Steven E; Mathew, Anne; Mitra, Sayan; Manivannan, Sathiya N; Simcox, Amanda

    2012-01-01

    In vivo analysis of Drosophila melanogaster has enhanced our understanding of many biological processes, notably the mechanisms of heredity and development. While in vivo analysis of mutants has been a strength of the field, analyzing fly cells in culture is valuable for cell biological, biochemical and whole genome approaches in which large numbers of homogeneous cells are required. An efficient genetic method to derive Drosophila cell lines using expression of an oncogenic form of Ras (Ras(V12)) has been developed. Mutations in tumor suppressors, which are known to cause cell hyperproliferation in vivo, could provide another method for generating Drosophila cell lines. Here we screened Drosophila tumor suppressor mutations to test if they promoted cell proliferation in vitro. We generated primary cultures and determined when patches of proliferating cells first emerged. These cells emerged on average at 37 days in wild-type cultures. Using this assay we found that a Pten mutation had a strong effect. Patches of proliferating cells appeared on average at 11 days and the cultures became confluent in about 3 weeks, which is similar to the timeframe for cultures expressing Ras(V12). Three Pten mutant cell lines were generated and these have now been cultured for between 250 and 630 cell doublings suggesting the life of the mutant cells is likely to be indefinite. We conclude that the use of Pten mutants is a powerful means to derive new Drosophila cell lines.

  11. Loss of the tumor suppressor Pten promotes proliferation of Drosophila melanogaster cells in vitro and gives rise to continuous cell lines.

    Directory of Open Access Journals (Sweden)

    Steven E Justiniano

    Full Text Available In vivo analysis of Drosophila melanogaster has enhanced our understanding of many biological processes, notably the mechanisms of heredity and development. While in vivo analysis of mutants has been a strength of the field, analyzing fly cells in culture is valuable for cell biological, biochemical and whole genome approaches in which large numbers of homogeneous cells are required. An efficient genetic method to derive Drosophila cell lines using expression of an oncogenic form of Ras (Ras(V12 has been developed. Mutations in tumor suppressors, which are known to cause cell hyperproliferation in vivo, could provide another method for generating Drosophila cell lines. Here we screened Drosophila tumor suppressor mutations to test if they promoted cell proliferation in vitro. We generated primary cultures and determined when patches of proliferating cells first emerged. These cells emerged on average at 37 days in wild-type cultures. Using this assay we found that a Pten mutation had a strong effect. Patches of proliferating cells appeared on average at 11 days and the cultures became confluent in about 3 weeks, which is similar to the timeframe for cultures expressing Ras(V12. Three Pten mutant cell lines were generated and these have now been cultured for between 250 and 630 cell doublings suggesting the life of the mutant cells is likely to be indefinite. We conclude that the use of Pten mutants is a powerful means to derive new Drosophila cell lines.

  12. HCMV Infection Depress NGF Expression in Human Glioma Cells

    Institute of Scientific and Technical Information of China (English)

    Hai-tao WANG; Bin WANG; Zhi-jun LIU; Zhi-qiang BAI; Ling LI; Dong-meng QIAN; Zhi-yong YAN; Xu-xia SONG

    2009-01-01

    Human cytomegalovirus (HCMV) is the most common cause of congenital infection, resulting in birth defects such as microcephaly. In this study, RT-PCR and Western Blotting were performed to quantify the regulation of endogenic nerve growth factor expression in neuroglia cells by HCMV infection. The results showed that basal, endogenous NGF expression in U251 was unchanged during early HCMV infection. NGF expression is strongly down-regulated during the latent phase of infection. These results suggest that HCMV can depress the NGF expression in U251 cells.

  13. Over-expression of tetraspanin 8 in malignant glioma regulates tumor cell progression

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Si-Jian [Department of Neurosurgery, Rui Jin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200025 (China); Wu, Yue-Bing [Department of Internal Medicine Oncology, Hubei Cancer Hospital, Wuhan, Hubei 430079 (China); Cai, Shang [Department of Radiotherapy and Oncology, the Second Affiliated Hospital of Soochow University, Suzhou 21500 (China); Pan, Yi-Xin; Liu, Wei [Department of Stereotactic and Functional Neurosurgery, Rui Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025 (China); Bian, Liu-Guan [Department of Neurosurgery, Rui Jin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200025 (China); Sun, Bomin [Department of Stereotactic and Functional Neurosurgery, Rui Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025 (China); Sun, Qing-Fang, E-mail: sunqingfang11@163.com [Department of Neurosurgery, Rui Jin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200025 (China)

    2015-03-13

    Tumor cell invasion and proliferation remain the overwhelming causes of death for malignant glioma patients. To establish effective therapeutic methods, new targets implied in these processes have to be identified. Tetraspanin 8 (Tspn8) forms complexes with a large variety of trans-membrane and/or cytosolic proteins to regulate several important cellular functions. In the current study, we found that Tspn8 was over-expressed in multiple clinical malignant glioma tissues, and its expression level correlated with the grade of tumors. Tspn8 expression in malignant glioma cells (U251MG and U87MG lines) is important for cell proliferation and migration. siRNA-mediated knockdown of Tspn8 markedly reduced in vitro proliferation and migration of U251MG and U87MG cells. Meanwhile, Tspn8 silencing also increased the sensitivity of temozolomide (TMZ), and significantly increased U251MG or U87MG cell death and apoptosis by TMZ were achieved with Tspn8 knockdown. We observed that Tspn8 formed a complex with activated focal adhesion kinase (FAK) in both human malignant glioma tissues and in above glioma cells. This complexation appeared required for FAK activation, since Tspn8 knockdown inhibited FAK activation in U251MG and U87MG cells. These results provide evidence that Tspn8 contributes to the pathogenesis of glioblastoma probably by promoting proliferation, migration and TMZ-resistance of glioma cells. Therefore, targeting Tspn8 may provide a potential therapeutic intervention for malignant glioma. - Highlights: • Tspn8 is over-expressed in multiple clinical malignant glioma tissues. • Tspn8 expression is correlated with the grade of malignant gliomas. • Tspn8 knockdown suppresses U251MG/U87MG proliferation and in vitro migration. • Tspn8 knockdown significantly increases TMZ sensitivity in U251MG/U87MG cells. • Tspn8 forms a complex with FAK, required for FAK activation.

  14. MicroRNA-181b inhibits cellular proliferation and invasion of glioma cells via targeting Sal-like protein 4.

    Science.gov (United States)

    Zhou, Yu; Peng, Yong; Liu, Min; Jiang, Yugang

    2016-11-17

    MicroRNAs (miRs), a class of 18-25 nucleotides in length non-coding RNAs, are able to suppress gene expression by targeting complementary regions of mRNAs and inhibiting protein translation Recently, miR-181b was found to playa suppressive role in glioma, but the regulatory mechanism of miR-181b in the malignant phenotypes of glioma cells remains largely unclear. Here we found that miR-181b was significantly downregulated in glioma tissues when compared with normal brain tissues, and decreased miR-181b levels were significantly associated with high pathology grade and poor prognosis of patients with glioma. Moreover, miR-181b was also downregulated in glioma cell lines (U87, SHG44, U373, and U251) compared to normal astrocytes. Overexpression of miR-181b significantly decreased the proliferation, migration, and invasion of glioma U251 cells. Sal-like protein 4 (SALL4) was identified as a novel target gene of miR-181b in U251 cells. The expression of SALL4 was significantly upregulated in glioma tissues and cell lines, and an inverse correlation was observed between the miR-181b and SALL4 expression levels in glioma. Further investigation showed that the protein expression of SALL4 was negatively regulated by miR-181b in U251 cells. Knockdown of SALL4 significantly inhibited the proliferation, migration and invasion of U251 cells, while overexpression of SALL4 effectively reversed the suppressive effects of miR-181b on these malignant phenotypes of U251 cells. In conclusion, our study demonstrates that miR-181b has suppressive effects on the malignant phenotypes of glioma cells, partly at least, via directly targeting SALL4. Therefore, the miR-181b/SALL4 axis may become a potential therapeutic target for glioma.

  15. Optimization, Application, and Interpretation of Lactate Dehydrogenase Measurements in Microwell Determination of Cell Number and Toxicity

    NARCIS (Netherlands)

    Wolterbeek, H.T.; Van der Meer, A.J.G.M.

    2005-01-01

    The lactate dehydrogenase (LDH) assay was addressed for its sensitivity, disturbances by foaming, and cell number and size. Cells were from a U-251 MG grade IV human glioblastoma brain tumor cell line used in 100-µl well volumes. Cells were counted by microscopy and Coulter counting; assays were LDH

  16. Effect of Wild-type p53 Gene Transfection on the Growth and Radiotherapeutic Sensitivity of Human Glioma Cells

    Institute of Scientific and Technical Information of China (English)

    XIANG Wei; ZHU Xianli; ZHAO Hongyang

    2005-01-01

    To evaluate the effect of wild-type p53 gene on the growth and radiotherapeutic sensitivity of human glioma cells, plasmid PC53-SN3 carrying wild-type p53 gene was transfected into U251cells. p53 gene expression in transfected cells was detected by RT-PCR, and the cell growth inhibition and apoptosis in the absence or presence of irradiation were assessed by MTT and flow cytometry. The transfection of p53 gene into U251 cells was confirmed by RT-PCR. MTT showed that p53 gene alone induced strong inhibitory effect on the growth of U251 cells (inhibition rate (IR):(79.60±5.69) %). The killing effect of irradiation alone on U251 cells was not strong (IR: (17.06±4.35) %, (17.39±1.67) %, (18.73±4.68) %) and increased with the irradiation doses (3,6, 9 Gy). When combined treatment of wild-type p53 gene transfection and irradiation was used,the effect was significantly increased (IR:(80.60±5.35) %, (90.30±1.67) %, (91.30±2.01)%). The apoptosis rate of U251 cells induced by p53 gene transfection was 17.38 %. The rate induced by irradiation increased (4. 61%, 4. 84 %, 5.40 %) with the irradiation doses (3, 6, 9Gy). The apoptosis rate was also significantly increased (17.80 %, 20.03 %, 22.34%) after combined treatment of p53 and irradiation with different doses (3, 6, 9 Gy). It is concluded that wildtype p53 gene and irradiation could result in synergistic inhibitory effect on the growth of human glioma cells.

  17. The involvement of hematopoietic pre-B cell leukemia transcription factor-interacting protein in regulating epithelial-mesenchymal transition of human spinal glioblastoma.

    Science.gov (United States)

    Wang, Deliang; Wang, Li; Zhou, Yi; Zhao, Xinjun; Xiong, Hui

    2016-05-01

    To date, hematopoietic pre-B cell leukemia transcription factor-interacting protein (HPIP), a co-repressor for the transcription factor PBX, has been involved into the initiation and onset in a wide variety of cancers. However, the molecular mechanisms underlying HPIP-induced epithelial-mesenchymal transition (EMT) in the spinal glioblastoma have been under investigation. In the present study, spinal glioblastoma tissues, U87, and U251 cell lines were used and subjected to in vitro assays, such as RT-PCR, and Western blot. Here, in vitro assays revealed that HPIP mRNA and protein were highly expressed in five cases of spinal glioblastoma tissues, compared with non-tumor tissues. Subsequently, in vitro experiments demonstrated HPIP promoted the U87 and U251 cell growth and regulated the G1/S phase transitions in U87 and U251 cell cycle, respectively, accompanied by the increased expression of cyclin A2, cyclin B1, and cyclin D1. Furthermore, HPIP increased the expression of N-cadherin, Slug, and MMP2, and decreased the expression of E-cadherin. By contrast, knockdown of HPIP reversed HPIP-induced EMT biomarkers, migration, and invasion in U87 and U251 cells. In conclusion, our findings identified HPIP plays an important role in the progression and EMT of spinal glioblastoma, by which cell growth is improved. Thus, HPIP gene or protein could act as a useful target in the clinical practice.

  18. The Effects of Wild-type p53 Gene Transfection on the Growth and Chemotherapeutic Sensitivity of Human Gl ioma Cells

    Institute of Scientific and Technical Information of China (English)

    项炜; 朱贤立; 赵洪洋

    2002-01-01

    To evaluate the effects of wild-type p53 gene on the growth and chemotherapeutic sensitivity of human glioma cells, plasmid PC53-SN3 carrying wild-type p53 gene was transfected into U251 cells. p53 gene expression in transfected cells was detected by RT-PCR, the cell growth inhibition and apoptosis in either the absence or the presence of cisplatin was assessed by MTT and flow cytometry. The transfection of p53 gene into U251 cells was confirmed by RT-PCR. MTT showed that p53 gene by itself induced strong inhibition effect on the growth of U251 cells [inhibition rate,IR (79.60±5.69) %]. The killing effects of cisplatin by itself on U251 cells was not strong [IR (19.40±6. 69) %, (24.41±2. 68) %, (51.84±13. 38) %, (66. 22±5.02) %] and increased with the increase of cisplatin concentration (1, 2, 4, 8 μg/ml). When combined treatment of wildtype p53 gene transfection and cisplatin was used, that was significantly increased [IR (91.64+1.00) %, (94. 98±1.67) %, (95.32±2.01)%, (95. 65±1.00) %]. The apoptosis rate of U251cells induced by p53 gene transfection was 17.38%. That induced by cisplatin increased (5.71 %,5. 93 %, 6.27 %, and 6.81%) with the increase of cisplatin concentration (1, 2, 4, 8 μg/ml).The apoptosis rate was also significantly increased (23.50 %, 23. 54 %, 23.89 %, and 28.88 %)after combined treatment of p53 and cisplatin with different concentration (1, 2, 4, 8 μg/ml). It is concluded that wild-type p53 gene and cisplatin could result in synergistic inhibition effects on the growth of human glioma cells.

  19. Effect of neomycin on cell proliferation and expression of PDGF,VEGF,angiogenin in glioma cells%新霉素对脑胶质瘤细胞增殖及PDGF、VEGF和血管生成素表达的影响

    Institute of Scientific and Technical Information of China (English)

    赵佳; 郝利铭; 姜文华; 孔德霞; 李洪成; 周莉

    2014-01-01

    目的:探讨新霉素对脑胶质瘤细胞增殖及 PDGF、VEGF和血管生成素表达的影响。方法采用人脑胶质瘤细胞 U251,DMEM培养基添加10%胎牛血清培养。MTT细胞活性实验检测细胞增殖,Real Time PCR检测 mR-NA表达情况,酶联免疫吸附实验检测蛋白表达。结果 MTT结果表明,新霉素对 U251细胞增殖存在抑制作用,并以剂量依赖的方式进行,并发现新霉素的抑制作用随时间增强。Real Time PCR结果显示,新霉素作用后 U251细胞中PDGF、VEGF和血管生成素 mRNA 的表达都受到不同程度的抑制,分别降低了26.75%、38.23%和43.87%。ELISA分析表明新霉素能够降低PDGF、VEGF和血管生成素蛋白水平的表达。结论新霉素能够抑制脑胶质瘤细胞 U251中PDGF、VEGF和血管生成素的表达并抑制脑胶质瘤细胞增殖。%Objective To observe the effect of neomycin on cell proliferation and expression of PDGF,VEGF,angio-genin in U251 glioma cells.Methods The cell proliferation was analyzed using MTT.Real Time PCR and ELISA were applied to investigate the expression of PDGF,VEGF,angiogenin.Results The MTT results showed that neomycin positively inhibited the cell proliferation of U251 cells and the inhibition was enhanced by dose-dependent and time-de-pendent.Real Time PCR and ELISA results showed that neomycin inhibited the expression of PDGF,VEGF,angiogenin both on mRNA level and protein level.Conclusion Neomycin positively inhibited the cell proliferation and expression of PDGF,VEGF,angiogenin in U251 glioma cells.

  20. Role of bentonite clays on cell growth.

    Science.gov (United States)

    Cervini-Silva, Javiera; Ramírez-Apan, María Teresa; Kaufhold, Stephan; Ufer, Kristian; Palacios, Eduardo; Montoya, Ascención

    2016-04-01

    Bentonites, naturally occurring clays, are produced industrially because of their adsorbent capacity but little is known about their effects on human health. This manuscript reports on the effect of bentonites on cell growth behaviour. Bentonites collected from India (Bent-India), Hungary (Bent-Hungary), Argentina (Bent-Argentina), and Indonesia (Bent-Indonesia) were studied. All four bentonites were screened in-vitro against two human cancer cell lines [U251 (central nervous system, glioblastoma) and SKLU-1 (lung adenocarcinoma)] supplied by the National Cancer Institute (USA). Bentonites induced growth inhibition in the presence of U251 cells, and growth increment in the presence of SKLU-1 cells, showing that interactions between bentonite and cell surfaces were highly specific. The proliferation response for U251 cells was explained because clay surfaces controlled the levels of metabolic growth components, thereby inhibiting the development of high-grade gliomas, particularly primary glioblastomas. On the other hand, the proliferation response for SKLU-1 was explained by an exacerbated growth favoured by swelling, and concomitant accumulation of solutes, and their hydration and transformation via clay-surface mediated reactions.

  1. Effect of Monoamine Oxidase Inhibitor on the Differentiation of Malignant Glioma Cell%单胺氧化酶抑制剂诱导胶质瘤细胞的体外分化

    Institute of Scientific and Technical Information of China (English)

    邵根宝; 薄丹丹; 韩晓娟; 贺清华; 张严; 桑建荣

    2012-01-01

    To investigate the effect of monoamine oxidase inhibitor tranylcypromine (TCP) on the differentiation of human U251 glioma cells, we treated U251 cells with TCP and/or 100 nmol/L histone deacetylase inhibitor trychos-tatin A (TSA). The differentiation of U251 cells was observed with inverted microscopy. The cell proliferation and cell cycle distribution were determined by MTT assay and flow cytometry. respectively. Apoptosis was observed by Hoechst 33258 staining. The levels of differentiation-related genes were assessed by real-time PCR and Western blotting. TCP-induced differentiation was characterized by typical morphological changes, inhibition of cellular proliferation, accumulation of cells in the Gl phase of the cell cycle, decreased expression of the pluripotency transcription factors Oct4 and Sox2, and increased expression of glial fibrillary acid protein (GFAP). The combination of TCP and TSA treatment also triggered an over-expression of GFAP. These findings suggest that TCP may induce differentiation of U251 glioma cells, and the differentiation process may be promoted by histone deacetylase inhibitor TSA,%为研究单胺氧化酶抑制剂(TCP)对体外培养的入脑胶质瘤U251细胞的诱导分化作用,以不同浓度TCP单独或与100 nmol/L组蛋白去乙酰化酶抑制剂(TSA)联合处理U251细胞,采用倒置显微镜观察细胞形态学变化;噻唑蓝( MTT)比色法检测细胞增殖变化;流式细胞仪检测细胞周期变化;Hoechst 33258染色显示细胞凋亡;Real-time PCR和Western印迹法检测分化相关基因mRNA和蛋白表达水平的改变.结果表明:TCP可诱导细胞突起增多且变细长,抑制细胞增殖,阻滞细胞周期于G1期,抑制全能性转录因子Oct4和Sox2的表达,上调分化标志基因胶质纤维酸性蛋白(GFAP)的表达,TCP联合TSA也诱导了GFAP的高表达.这些结果提示:TCP可诱导胶质瘤U251细胞分化,TSA对TCP诱导细胞分化有协同作用.

  2. Bioactive form of resveratrol in glioblastoma cells and its safety for normal brain cells

    Directory of Open Access Journals (Sweden)

    Xiao-Hong Shu

    2013-05-01

    Full Text Available ABSTRACTBackground: Resveratrol, a plant polyphenol existing in grapes and many other natural foods, possesses a wide range of biological activities including cancer prevention. It has been recognized that resveratrol is intracellularly biotransformed to different metabolites, but no direct evidence has been available to ascertain its bioactive form because of the difficulty to maintain resveratrol unmetabolized in vivo or in vitro. It would be therefore worthwhile to elucidate the potential therapeutic implications of resveratrol metabolism using a reliable resveratrol-sensitive cancer cells.Objective: To identify the real biological form of trans-resveratrol and to evaluate the safety of the effective anticancer dose of resveratrol for the normal brain cells.Methods: The samples were prepared from the condition media and cell lysates of human glioblastoma U251 cells, and were purified by solid phase extraction (SPE. The samples were subjected to high performance liquid chromatography (HPLC and liquid chromatography/tandem mass spectrometry (LC/MS analysis. According to the metabolite(s, trans-resveratrol was biotransformed in vitro by the method described elsewhere, and the resulting solution was used to treat U251 cells. Meanwhile, the responses of U251 and primarily cultured rat normal brain cells (glial cells and neurons to 100μM trans-resveratrol were evaluated by multiple experimental methods.Results: The results revealed that resveratrol monosulfate was the major metabolite in U251 cells. About half fraction of resveratrol monosulfate was prepared in vitro and this trans-resveratrol and resveratrol monosulfate mixture showed little inhibitory effect on U251 cells. It is also found that rat primary brain cells (PBCs not only resist 100μM but also tolerate as high as 200μM resveratrol treatment.Conclusions: Our study thus demonstrated that trans-resveratrol was the bioactive form in glioblastoma cells and, therefore, the biotransforming

  3. Targeting Netrin-1 in glioblastoma stem-like cells inhibits growth, invasion, and angiogenesis.

    Science.gov (United States)

    Sanvoranart, Tanwarat; Supokawej, Aungkura; Kheolamai, Pakpoom; U-Pratya, Yaowalak; Poungvarin, Niphon; Sathornsumetee, Sith; Issaragrisil, Surapol

    2016-11-01

    Glioblastoma (GBM) is an aggressive malignant brain tumor that still lacks effective therapy. Glioblastoma stem cells (GBM-SCs) were identified to contribute to aggressive phenotypes and poor clinical outcomes for GBM. Netrin-1, an axon guidance molecule, has been found in several tumors in adults. However, the role of Netrin-1 in GBM-SCs remains largely unknown. In this study, CD133-positive U251 GBM cells were used as a putative GBM-SC population to identify the functions of Netrin-1. Using lentiviral transduction, Netrin-1 miR RNAi vectors were transduced into CD133-positive U251 cells. We demonstrated that cell proliferation and survival were decreased following targeted deletion of Netrin-1. Cell invasion was dramatically diminished in Netrin-1 knockdown GBM-SCs. Moreover, Netrin-1 knockdown GBM-SCs exhibited less proangiogenic activity. In conclusion, Netrin-1 may represent a therapeutic target in glioblastoma.

  4. Ginsenoside Rh2 inhibits glioma cell proliferation by targeting microRNA-128

    Institute of Scientific and Technical Information of China (English)

    Nan WU; Guo-cai WU; Rong HU; Mei LI; Hua FENG

    2011-01-01

    Aim: To examine the influence of ginsenoside Rh2 (Rh2), a triterpene saponin extracted from the traditional medicinal plant ginseng,on the expression of miRNAs in human glioma cells.Methods: The expression profile of miRNA (miR) was analyzed in human U251, T98MG and A172 glioma cells using a miRNA array and quantitative real-time PCR. Cell viability was assessed using a colorimetric assay (cell counting kit-8). Transfection of miR-128was performed using Lipofectamine 2000. Caspase 3 activity was determined using a caspase colorimetric assay kit. Apoptosis was assessed using annexin V and propidium iodide staining. Protein expression was determined with Western blot analysis. miRNA-128targeting activity was measured using a luciferase reporter assay.Results: In U251 cells treated with Rh2 (12 μg/mL), 14 of 452 human miRNAs were up-regulated and 12 were down-regulated as detected with the miRNA array assay. The up-regulation of miR-128 by Rh2 was further verified in human U251, T98MG and A172 cells using quantitative real-time PCR. In U251 cells, transfection of a miR-128 inhibitor (50 nmol/L) prevented the overexpression of miR128 by Rh2, and significantly blunted Rh2-induced cytotoxicity, apoptosis, caspase 3 activation, transcriptional activation of E2F3a, a miR-128 target gene, as well as E2F3a protein expression.Conclusion: The anti-proliferative effect of Rh2 in human glioma cells was mediated in part through up-regulation of miRNA-128 expression.

  5. Human glioma expresses high level of Snail and promotes tumor cell invasiveness%人脑胶质瘤高表达Snail促进肿瘤细胞的侵袭

    Institute of Scientific and Technical Information of China (English)

    施立海; 李健; 赵继宗

    2011-01-01

    目的:观察Snail蛋白在人脑胶质瘤组织中的表达情况,探讨Snail表达对人脑胶质瘤U251细胞侵袭的影响.方法:收集首都医科大学附属北京天坛医院及北京安贞医院神经外科手术切除的脑胶质瘤组织65例,应用免疫组织化学S-P法检测人脑胶质瘤组织中Snail的表达.体外化学合成Snail序列特异性小干扰RNA(Snail-siRNA),应用脂质体介导转染U251细胞;RT-PCR、Western blotting检测转染后U251细胞中Snail mRNA和蛋白、E-cadherin蛋白表达水平变化,并采用Transwell小室检测转染后U251细胞侵袭能力的变化.结果:与正常脑组织相比,人脑胶质瘤组织中Snail蛋白阳性表达率明显增强(66.2% vs O,P<0.01),并且Ⅰ~Ⅱ级的胶质瘤组织阳性Snail阳性率明显低于Ⅲ一Ⅳ级(44.8%vs83.3%,P<0.01).Snail-siRNA转染抑制U251细胞中Snail mRNA和蛋白的表达.Snail-siRNA转染组U251细胞中E-cadherin蛋白的表达明显高于Ctrl-siRNA组与未转染组(0.64±0.21 vs 0.15±0.16,0.21±0.19,P<0.01).Snail-siRNA转染显著抑制U251细胞的侵袭(87.0±2.4 vs 140.0±4.9,136.0±5.3;P<0.05).结论:人脑胶质瘤组织高表达Snail蛋白,siRNA干扰Snail蛋白的表达可抑制胶质瘤U251细胞的侵袭.%Objective:To investigate the expression of Snail protein in human glioma tissues and study the effect of Snail on human glioma U251 cells. Methods: Sixty-five specimens from glioma patients, who were diagnosed in Beijing Anzhen Hospital and Beijing Tiantan Hospital, were included in this study. Immunohistochemistry S-P was used to detect Snail protein expression in human glioma tissues. Snail specific small interference RNA (Snail-siRNA) was constructed and transfected into U251 cells by lipofectamine. The expressions of Snail mRNA and protein and E-cadherin protein in transfected-U251 cells were investigated by RT-PCR and Western blotting analysis, respectively; and the invasion ability of transfected-U251 cells was investigated by

  6. Inhibitory Effects of Ginsenoside Rb1 on Apoptosis Caused by HSV-1 in Human Glioma Cells

    Institute of Scientific and Technical Information of China (English)

    Yuan-Yuan Liang; Bin Wang; Dong-Meng Qian; Ling Li; Zhi-Hao Wang; Ming Hu; Xu-Xia Song

    2012-01-01

    To investigate the inhibitory effects of Ginsenoside Rb1 (GRb1) on apoptosis caused by Herpes Simplex Virus-1 (HSV-1) in Human Glioma Cells (U251),U251 cells were infected by HSV-1 at a multiplicity of infection of 5 and GRb1,GRb1+HSV-1,HSV-1 and control groups.MTT and cell apoptosis assays were used to detect the inhibitory effects of GRbl on the apoptosis of U251 cells that caused by HSV-1 infection for various concentrations of drug and virus treatments by MTT assay.We found that in the 400 μg/mL GRbl and 400 μg/mL GRbl+HSV-1 groups,MTT values were higher than control group at all times (P<0.05).Moreover,the apoptosis rate in the 400 μg/mL GRb1+HSV-1 group was lower than the HSV-1 group (P<0.05).These results confirmed that,at appropriate concentrations,GRb 1 could inhibit nerve cell apoptosis in HSV-1 infections.

  7. Gallic acid suppresses cell viability, proliferation, invasion and angiogenesis in human glioma cells

    OpenAIRE

    Lu, Yong; Jiang, Feng; JIANG, Hao; Wu, Kalina; Zheng, Xuguang; Cai, Yizhong; Katakowski, Mark; Chopp, Michael; To, Shing-Shun Tony

    2010-01-01

    Gallic acid, an organic acid, also known as 3,4,5-trihydroxybenzoic acid, is cytotoxic against certain cancer cells, without harming normal cells. The objective of this study is to evaluate whether gallic acid can inhibit glioma cell viability, proliferation, invasion and reduce glioma cell mediated angiogenesis. Treatment of U87 and U251n glioma cells with gallic acid inhibited cell viability in a dose- and time-dependent manner. BrdU and tube formation assays indicated that gallic acid sign...

  8. 银铁纳米复合材料的脑胶质瘤放射增敏作用%Enhancing radiosensitivity of glioma cells with Ag/Fe3O4 nanoparticles

    Institute of Scientific and Technical Information of China (English)

    柴湘婷; 刘连科

    2011-01-01

    目的 研究银/四氧化三铁纳米复合材料(Ag/Fe3O4)对人源性脑胶质瘤U251细胞的放射敏感性的影响.方法 人源性脑胶质瘤U251细胞分为对照组、Ag/Fe3O4组、放疗组、Ag/Fe3O4复合放疗组.用集落形成实验检测Ag/Fe3O4对U251细胞放疗效果;流式细胞术检测银纳米颗粒(AgNPs)对细胞周期和凋亡率的影响.结果 Ag/Fe3O4能够引起U251细胞G2/M期阻滞,并使细胞放疗后凋亡率显著提高(P<0.05).结论 可利用Ag/Fe3O4纳米颗粒提高脑胶质瘤放射敏感性.%Objective To study the effect of Ag/Fe3O4 nanoparticles on the efficacy of radiosensitivity enhancement of U251 glioma cells. Methods U251 cells were divided into four groups of control, Ag/Fe3 O4, radiotherapy and Ag/Fe3 O4 combined with radiotherapy. The effect of Ag/Fe3O4 nanoparticles on radiosensitivity of glioma cells was detected by colony-forming assay. The cell cycles and apoptosis after irritation were tested by flow cytometry. Results Ag/Fe3 O4 nanoparticles could induce cell cycle in G2/M arrest and increased cells apoptosis rate after radiotherapy (P<0. 05). Conclusion The Ag/Fe3O4 nanostructures can significantly enhance radiosensitivity of glioma cells.

  9. Deciphering the Mechanism of Alternative Cleavage and Polyadenylation in Mantle Cell Lymphoma (MCL)

    Science.gov (United States)

    2014-10-01

    express- ion in glioblastoma cells enhances their tumorigenic properties and increases tumour size,whereasCFIm25overexpression reduces these...inCFIm25knockdowncells haveoverall higher express- ion levels (Fig. 2d).Weobserved that 64%of transcriptswith shortened 39UTRs exhibited significantly increased...lines used (HeLa, U251 and LN229) were cultured in DMEM supplemented with 10% FBS (11% penicillin and streptomy- cin) in a 5% CO2 incubator at 37 uC

  10. MicroRNA-130b promotes cell proliferation and invasion by inhibiting peroxisome proliferator-activated receptor-γ in human glioma cells.

    Science.gov (United States)

    Gu, Jian-Jun; Zhang, Jian-He; Chen, Hong-Jie; Wang, Shou-Sen

    2016-06-01

    MicroRNA-130b (miR-130b) is a novel tumor-related miRNA that has been found to be involved in several biological processes. However, there is limited evidence regarding the role of miR-130b in the tumorigenesis of human gliomas. In the present study, reverse transcription-quantitative polymerase chain reaction (RT-qPCR) assays were used to quantify miR-130b expression levels in human glioma tissues and glioma cell lines (U251, U87, SNB19 and LN229). The expression level of miR-130b was found to be markedly higher in human glioma tissues than in non‑neoplastic brain specimens. Specifically, higher expression levels of miR‑130b were observed in the glioma cell lines, compared with those in normal human astrocytes (NHA). We also confirmed that miR‑130b interacted with the 3'-untranslated region of peroxisome proliferator‑activated receptor-γ (PPAR‑γ), which negatively affected the protein levels of E-cadherin. Furthermore, its effects on cell proliferation and invasion were examined using CCK8, colony formation, cell cycle and Transwell assays. We found that the upregulation of miR-130b induced cell proliferation, decreased the percentage of cells in the G0/G1 phase and enhanced the invasiveness of U251 glioma cells whereas the downregulation of miR-130b exerted opposing effects. Moreover, it was demonstrated that the downregulation of miR‑130b in U251 glioma cells restored the expression of PPAR-γ and E-cadherin, and inhibited the expression of β-catenin. Notably, PPAR-γ knockdown abolished the inhibitory effect of miR-130b inhibitor on the proliferation and invasivness of U251 cells. Taken together, these findings suggest that miR‑130b promotes the proliferation and invasion of U251 glioma cells by inhibiting PPAR-γ.

  11. In vitro effect of p21WAF-1/CIP1 gene on growth of human glioma cells mediated by EGFR targeted non-viral vector GE7 system

    Institute of Scientific and Technical Information of China (English)

    陈永新; 许秀兰; 张光霁; 王韦; 金海英; 卢亦成; 朱诚; 顾健人

    2003-01-01

    Objective: To construct the EGFR targeted non-viral vector GE7 system and explore the in vitro effect of p21WAF-1/CIP1 gene on growth of human glioma cells mediated by the GE7 system. Methods: The EGFR targeted non-viral vector GE7 gene delivery system was constructed. The malignant human glioma cell line U251MG was transfected in vitro with β-galactosidase gene(reporter gene) and p21WAF-1/CIP1 gene (therapeutic gene) using the GE7 system. By means of X-gal staining, MTS and FACS, the transfection efficiency of exogenous gene and apoptosis rate of tumor cells were examined. The expression of p21WAF-1/CIP1 gene in transfected U251MG cell was examined by immunohistochemistry staining. Results: The highest transfer rate of exogenous gene was 70%. After transfection with p21WAF-1/CIP1 gene, the expression of WAF-1 increased remarkably and steadily; the growth of U251MG cells were inhibited evidently. FACS examination showed G1 arrest. The average apoptosis rate was 25.2%. Conclusion: GE7 system has the ability to transfer exogenous gene to targeted cells efficiently, and expression of p21WAF-1/CIP1 gene can induce apoptosis of glioma cell and inhibit its growth.

  12. Lycopene Pretreatment Ameliorates Acute Ethanol Induced NAD+ Depletion in Human Astroglial Cells

    Directory of Open Access Journals (Sweden)

    Jade Guest

    2015-01-01

    Full Text Available Excessive alcohol consumption is associated with reduced brain volume and cognition. While the mechanisms by which ethanol induces these deleterious effects in vivo are varied most are associated with increased inflammatory and oxidative processes. In order to further characterise the effect of acute ethanol exposure on oxidative damage and NAD+ levels in the brain, human U251 astroglioma cells were exposed to physiologically relevant doses of ethanol (11 mM, 22 mM, 65 mM, and 100 mM for ≤ 30 minutes. Ethanol exposure resulted in a dose dependent increase in both ROS and poly(ADP-ribose polymer production. Significant decreases in total NAD(H and sirtuin 1 activity were also observed at concentrations ≥ 22 mM. Similar to U251 cells, exposure to ethanol (≥22 mM decreased levels of NAD(H in primary human astrocytes. NAD(H depletion in primary astrocytes was prevented by pretreatment with 1 μM of lycopene for 3.5 hours. Unexpectedly, in U251 cells lycopene treatment at concentrations ≥ 5 μM resulted in significant reductions in [NAD(H]. This study suggests that exposure of the brain to alcohol at commonly observed blood concentrations may cause transitory oxidative damage which may be at least partly ameliorated by lycopene.

  13. Knockdown of long noncoding RNA H19 sensitizes human glioma cells to temozolomide therapy

    Science.gov (United States)

    Jiang, Pengfei; Wang, Ping; Sun, Xiaoling; Yuan, Zhongshun; Zhan, Rucai; Ma, Xiangyu; Li, Weiguo

    2016-01-01

    Temozolomide (TMZ) is commonly used in glioma chemotherapy. However, a great clinical challenge for TMZ is chemoresistance. H19 transcripts are recognized as long noncoding RNAs, which potentially interact with chromatin-modifying complexes to regulate gene expression via epigenetic changes. Our data based on glioma patients showed that the expression of H19 was significantly upregulated in TMZ-resistant tumors compared with the TMZ-sensitive tumors. To determine the function of H19 in glioma, cell lines U87 and U251 were exposed to TMZ to establish TMZ-resistant clones U87TMZ and U251TMZ. In U87TMZ and U251TMZ, the expression level of H19 transcripts was increased compared to wild-type or nonresistant clones, as determined by real-time quantitative reverse transcription polymerase chain reaction. Concomitant treatment with small interfering RNA specifically targeting H19 and TMZ in resistant glioma clones resulted in decreased IC50 values for TMZ, and increased apoptotic rates than control small interfering RNA-treated cells. This was also evident by the increased PARP cleavage in resistant cells exposed to TMZ + si-H19. Furthermore, the reduced expression of H19 altered major drug resistance genes, such as MDR, MRP, and ABCG2, both at the mRNA and protein levels. Taken together, these findings suggest that H19 plays an important role in the development of TMZ resistance, and may represent a novel therapeutic target for TMZ-resistant gliomas. PMID:27366087

  14. MiR-18a regulates the proliferation, migration and invasion of human glioblastoma cell by targeting neogenin

    Energy Technology Data Exchange (ETDEWEB)

    Song, Yichen, E-mail: jeff200064017@163.com [Department of Neurosurgery, Shengjing Hospital of China Medical University, Shenyang 110004 (China); Wang, Ping, E-mail: pingwang8000@163.com [Department of Neurobiology, College of Basic Medicine, China Medical University, Shenyang 110001 (China); Institute of Pathology and Pathophysiology, China Medical University, Shenyang 110001 (China); Zhao, Wei, E-mail: 15669746@qq.com [Department of Neurobiology, College of Basic Medicine, China Medical University, Shenyang 110001 (China); Institute of Pathology and Pathophysiology, China Medical University, Shenyang 110001 (China); Yao, Yilong, E-mail: yaoyilong_322@163.com [Department of Neurosurgery, Shengjing Hospital of China Medical University, Shenyang 110004 (China); Liu, Xiaobai, E-mail: paganizonda1991@qq.com [The 96th Class, 7-year Program, China Medical University, Shenyang, Liaoning Province 110001 (China); Ma, Jun, E-mail: majun_724@163.com [Department of Neurobiology, College of Basic Medicine, China Medical University, Shenyang 110001 (China); Institute of Pathology and Pathophysiology, China Medical University, Shenyang 110001 (China); Xue, Yixue, E-mail: xueyixue888@163.com [Department of Neurobiology, College of Basic Medicine, China Medical University, Shenyang 110001 (China); Institute of Pathology and Pathophysiology, China Medical University, Shenyang 110001 (China); Liu, Yunhui, E-mail: liuyh@sj-hospital.org [Department of Neurosurgery, Shengjing Hospital of China Medical University, Shenyang 110004 (China)

    2014-05-15

    MiR-17-92 cluster has recently been reported as an oncogene in some tumors. However, the association of miR-18a, an important member of this cluster, with glioblastoma remains unknown. Therefore, this study aims to investigate the expression of miR-18a in glioblastoma and its role in biological behavior of U87 and U251 human glioblastoma cell lines. Quantitative RT-PCR results showed that miR-18a was highly expressed in glioblastoma tissues and U87 and U251 cell lines compared with that in human brain tissues and primary normal human astrocytes, and the expression levels were increased along with the rising pathological grades of glioblastoma. Neogenin was identified as the target gene of miR-18a by dual-luciferase reporter assays. RT-PCR and western blot results showed that its expression levels were decreased along with the rising pathological grades of glioblastoma. Inhibition of miR-18a expression was established by transfecting exogenous miR-18a inhibitor into U87 and U251 cells, and its effects on the biological behavior of glioblastoma cells were studied using CCK-8 assay, transwell assay and flow cytometry. Inhibition of miR-18a expression in U87 and U251 cells significantly up-regulated neogenin, and dramatically suppressed the abilities of cell proliferation, migration and invasion, induced cell cycle arrest and promoted cellular apoptosis. Collectively, these results suggest that miR-18a may regulate biological behavior of human glioblastoma cells by targeting neogenin, and miR-18a can serve as a potential target in the treatment of glioblastoma. - Highlights: • MiR-18a was highly expressed in glioblastoma tissues and U87 and U251 cell lines. • Neogenin was identified as the target gene of miR-18a. • Neogenin expressions were decreased along with the rising pathological grades of glioblastoma. • Inhibition of miR-18a suppressed biological behavior of glioma cells by up-regulating neogenin.

  15. Synthesis of tumor-targeted folate conjugated fluorescent magnetic albumin nanoparticles for enhanced intracellular dual-modal imaging into human brain tumor cells.

    Science.gov (United States)

    Wang, Xueqin; Tu, Miaomiao; Tian, Baoming; Yi, Yanjie; Wei, ZhenZhen; Wei, Fang

    2016-11-01

    Superparamagnetic iron oxide nanoparticles (SPIO NPs), utilized as carriers are attractive materials widely applied in biomedical fields, but target-specific SPIO NPs with lower toxicity and excellent biocompatibility are still lacking for intracellular visualization in human brain tumor diagnosis and therapy. Herein, bovine serum albumin (BSA) coated superparamagnetic iron oxide, i.e. γ-Fe2O3 nanoparticles (BSA-SPIO NPs), are synthesized. Tumor-specific ligand folic acid (FA) is then conjugated onto BSA-SPIO NPs to fabricate tumor-targeted NPs, FA-BSA-SPIO NPs as a contrast agent for MRI imaging. The FA-BSA-SPIO NPs are also labeled with fluorescein isothiocyanate (FITC) for intracellular visualization after cellular uptake and internalization by glioma U251 cells. The biological effects of the FA-BSA-SPIO NPs are investigated in human brain tumor U251 cells in detail. These results show that the prepared FA-BSA-SPIO NPs display undetectable cytotoxicity, excellent biocompatibility, and potent cellular uptake. Moreover, the study shows that the made FA-BSA-SPIO NPs are effectively internalized for MRI imaging and intracellular visualization after FITC labeling in the targeted U251 cells. Therefore, the present study demonstrates that the fabricated FITC-FA-BSA-SPIO NPs hold promising perspectives by providing a dual-modal imaging as non-toxic and target-specific vehicles in human brain tumor treatment in future.

  16. GOLPH3 promotes glioblastoma cell migration and invasion via Snail%Snail 介导 GOLPH3对人脑胶质瘤细胞迁移和侵袭作用的研究

    Institute of Scientific and Technical Information of China (English)

    赵伟; 张旭; 陆冬; 张昊; 石琼; 周秀萍; 于如同

    2015-01-01

    Objective To study the role and mechanism of Golgi phosphoprotein 3(GOLPH3) in glioma cell migration and invasion .Methods The effect of GOLPH3 on the expression of YB1,snail and MMP2 was examined by Western blotting and RT-PCR respectively .After down-regulation of snail, the protein level of YB1 were analyzed by western blotting ,cell migration and invasion ability were examined by wound healing and invasion assay respectively .After GOLPH3 over-expression with or without Snail down-regulation,GOLPH3,Snail and YB1 protein expression levels in U251 glioma cells were determined by western blotting , and the ability of cell migration and invasion were examined by wound healing and invasion assay respectively .Results Down-regulation of GOLPH3 decreased the protein and mRNA levels of YB 1 and mRNA levels of MMP2.Down-regulation of GOLPH3 decreased the protein level of Snailwhile over-expression of GOLPH3 showed contrary effect . Down-regulation of Snail decreased the level of YB 1 and inhibited the migration and invasion of U 251 cells.Over-expression of GOLPH3 inducing U251 cell migration and invasion were blocked by Snail down-regulation.Conclusion Down-regulation of GOLPH3 inhibited glioma U251 cell migration and invasion through regulating Snail and YB 1 expression .%目的:研究GOLPH3影响脑胶质瘤细胞的迁移和侵袭能力及机制。方法观察GFP荧光和Western blot鉴定过表达或下调GOLPH3的U251细胞;分别应用RT-PCR、Western blot 实验检测GOLPH3对Y-box binding protein 1(YB1)蛋白及核酸水平、对MMP-2及Snail的调节;采用Snail siRNA下调Snail的表达后,Western blot检测Snail及YB1的水平,细胞划痕实验和Transwell侵袭实验检测Snail对细胞的侵袭迁移能力的影响;Western blot检测在过表达GOLPH3的U251细胞中下调Snail后,GOLPH3、Snail及YB1的水平;同时应用细胞划痕实验和Transwell 侵袭实验检测此共转实验对细胞迁移和侵袭能

  17. MicroRNA-9 inhibits vasculogenic mimicry of glioma cell lines by suppressing Stathmin expression.

    Science.gov (United States)

    Song, Yuwen; Mu, Luyan; Han, Xuezhe; Li, Qingla; Dong, Baijing; Li, Hulun; Liu, Xiaoqian

    2013-12-01

    The purpose of this study was to investigate the functions of microRNA-9, which is a tissue-specific microRNA in central nervous system, in the vasculogenic mimicry (VM) of glioma cell lines in vitro and in vivo. Glioma cell lines U87MG, U251 and SHG44 were transfected with microRNA-9 mimic, microRNA-9 inhibitor or scramble sequences. The amount of microRNA-9 and Stathmin (STMN1) mRNA was determined by quantitative real-time PCR, and the protein expression of STMN1 was determined by western blot. Cell proliferation and apoptosis were assessed. The interactions between the 3'UTR of STMN1 and miR-9 was determined by luciferase reporter assay. The VM capacity in vitro was evaluated using VM formation assay, and the rescue experiment of STMN1 was carried out in U251 cells. The in vivo experiment was applied with animal models implanted with U87MG cells.MicroRNA-9 mimic transfection reduced proliferation and increased apoptosis in glioma cell lines (p < 0.05). MicroRNA-9 mimic up-regulated STMN1 mRNA levels but reduced its protein levels (p < 0.05), and luciferase activity of STMN1 was suppressed by microRNA-9 mimic transfection (p < 0.05). Furthermore, microRNA-9 mimic transfection suppressed tumor volume growth, as well as VM both in vitro and in vivo. The cell viability and microtube density were upregulated in U251 cells after STMN1 up-regulation (p < 0.05). STMN1 is a target of microRNA-9, and microRNA-9 could modulate cell proliferation, VM and tumor volume growth through controlling STMN1 expression. MicroRNA-9 and its targets may represent a novel panel of molecules for the development of glioma treatment.

  18. RELATIONSHIP BETWEEN TELOMERE LENGTH AND RADIOSENSITIVITY IN VARIOUS HUMAN CANCER CELL LINES

    Institute of Scientific and Technical Information of China (English)

    CAO Zhen; ZHOU Yun-feng; LUO Zhi-guo; XIAO Chuang-ying; DAI Jing; PAN Dong-feng; ZHOU Fu-xiang; XIE Cong-hua; ZHANG Gong; LIU Shi-quan

    2005-01-01

    Objective: To investigate the relationship between telomere length and radiosensitivity in various human cancer cell lines with the expectation to find a valid and common predictor of radiosensitivity for different cancers. Methods: Eight human cancer cell lines were used, including five human breast cancer cell lines (ZR-75-30, MCF-7, MDA-MB-435S, T-47-D,F539-1590), two human larynx squamous carcinoma cell lines (Hep-2 and Hep-2R) and a human malignant glioma cell line(U251). Among them, the radioresistant cell line Hep-2R was isolated and established from a radiosensitive human larynx squamous carcinoma cell line Hep-2 by our center. The radiobiological characteristics of the eight lines were analyzed by the method of colony-forming assay and the radiosensitivity parameters were calculated. Telomere length was analyzed by TRF(mean Telomere Restriction Fragments) length assay. Results: The radioresistance of Hep-2R cell line proved to be stable in long-term passaged cultures as well as in frozen samples. Radiosensitivity parameters are different among those lines. The SF2 values of Hep-2 and U251 are 0.4148 and 0.7520, respectively; The SF2 values of breast cancer cell lines are between those of Hep-2 and U251. The TRF of Hep-2R is 11.12Kb, longer than three times that of its parental counterpart. There is a positive correlation both between SF2 and TRF (r=0.786, P<0.05), and between Do and TRF (r=0.905, P<0.01). Conclusion:It is concluded that radiosensitivity and telomere length (TRF) are negatively correlated, TRF could be a valid predictor for radiosensitivity.

  19. Metformin and Ara-a Effectively Suppress Brain Cancer by Targeting Cancer Stem/Progenitor Cells

    Science.gov (United States)

    Mouhieddine, Tarek H.; Nokkari, Amaly; Itani, Muhieddine M.; Chamaa, Farah; Bahmad, Hisham; Monzer, Alissar; El-Merahbi, Rabih; Daoud, Georges; Eid, Assaad; Kobeissy, Firas H.; Abou-Kheir, Wassim

    2015-01-01

    Background: Gliomas and neuroblastomas pose a great health burden worldwide with a poor and moderate prognosis, respectively. Many studies have tried to find effective treatments for these primary malignant brain tumors. Of interest, the AMP-activated protein kinase (AMPK) pathway was found to be associated with tumorigenesis and tumor survival, leading to many studies on AMPK drugs, especially Metformin, and their potential role as anti-cancer treatments. Cancer stem cells (CSCs) are a small population of slowly-dividing, treatment-resistant, undifferentiated cancer cells that are being discovered in a multitude of cancers. They are thought to be responsible for replenishing the tumor with highly proliferative cells and increasing the risk of recurrence. Methods: Metformin and 9-β-d-Arabinofuranosyl Adenine (Ara-a) were used to study the role of the AMPK pathway in vitro on U251 (glioblastoma) and SH-SY5Y (neuroblastoma) cell lines. Results: We found that both drugs are able to decrease the survival of U251 and SH-SY5Y cell lines in a 2D as well as a 3D culture model. Metformin and Ara-a significantly decreased the invasive ability of these cancer cell lines. Treatment with these drugs decreased the sphere-forming units (SFU) of U251 cells, with Ara-a being more efficient, signifying the extinction of the CSC population. However, if treatment is withdrawn before all SFUs are extinguished, the CSCs regain some of their sphere-forming capabilities in the case of Metformin but not Ara-a treatment. Conclusion: Metformin and Ara-a have proved to be effective in the treatment of glioblastomas and neuroblastomas, in vitro, by targeting their cancer stem/progenitor cell population, which prevents recurrence. PMID:26635517

  20. Metformin and Ara-a Effectively Suppress Brain Cancer by Targeting Cancer Stem/Progenitor Cells

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    Tarek H. Mouhieddine

    2015-11-01

    Full Text Available Background: Gliomas and neuroblastomas pose a great health burden worldwide with a poor and moderate prognosis, respectively. Many studies have tried to find effective treatments for these primary malignant brain tumors. Of interest, the AMP-activated protein kinase (AMPK pathway was found to be associated with tumorigenesis and tumor survival, leading to many studies on AMPK drugs, especially Metformin, and their potential role as anti-cancer treatments. Cancer stem cells (CSCs are a small population of slowly-dividing, treatment-resistant, undifferentiated cancer cells that are being discovered in a multitude of cancers. They are thought to be responsible for replenishing the tumor with highly proliferative cells and increasing the risk of recurrence. Methods: Metformin and 9-β-d-Arabinofuranosyl Adenine (Ara-a were used to study the role of the AMPK pathway in vitro on U251 (glioblastoma and SHSY-5Y (neuroblastoma cell lines.Results: We found that both drugs are able to decrease the survival of U251 and SH-SY5Y cell lines in a 2D as well as a 3D culture model. Metformin and Ara-a significantly decreased the invasive ability of these cancer cell lines. Treatment with these drugs decreased the sphere-forming units (SFU of U251 cells, with Ara-a being more efficient, signifying the extinction of the CSC population. However, if treatment is withdrawn before all SFUs are extinguished, the CSCs regain some of their sphere-forming capabilities in the case of Metformin but not Ara-a treatment. Conclusion: Metformin and Ara-a have proved to be effective in the treatment of glioblastomas and neuroblastomas, in vitro, by targeting their cancer stem/progenitor cell population, which prevents recurrence.

  1. Mechanistic Rationale to Target PTEN-Deficient Tumor Cells with Inhibitors of the DNA Damage Response Kinase ATM.

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    McCabe, Nuala; Hanna, Conor; Walker, Steven M; Gonda, David; Li, Jie; Wikstrom, Katarina; Savage, Kienan I; Butterworth, Karl T; Chen, Clark; Harkin, D Paul; Prise, Kevin M; Kennedy, Richard D

    2015-06-01

    Ataxia telangiectasia mutated (ATM) is an important signaling molecule in the DNA damage response (DDR). ATM loss of function can produce a synthetic lethal phenotype in combination with tumor-associated mutations in FA/BRCA pathway components. In this study, we took an siRNA screening strategy to identify other tumor suppressors that, when inhibited, similarly sensitized cells to ATM inhibition. In this manner, we determined that PTEN and ATM were synthetically lethal when jointly inhibited. PTEN-deficient cells exhibited elevated levels of reactive oxygen species, increased endogenous DNA damage, and constitutive ATM activation. ATM inhibition caused catastrophic DNA damage, mitotic cell cycle arrest, and apoptosis specifically in PTEN-deficient cells in comparison with wild-type cells. Antioxidants abrogated the increase in DNA damage and ATM activation in PTEN-deficient cells, suggesting a requirement for oxidative DNA damage in the mechanism of cell death. Lastly, the ATM inhibitor KU-60019 was specifically toxic to PTEN mutant cancer cells in tumor xenografts and reversible by reintroduction of wild-type PTEN. Together, our results offer a mechanistic rationale for clinical evaluation of ATM inhibitors in PTEN-deficient tumors.

  2. Dual regulatory role for phosphatase and tensin homolog in specification of intestinal endocrine cell subtypes

    Institute of Scientific and Technical Information of China (English)

    Sébastien AB Roy; Marie-Josée Langlois; Julie C Carrier; Fran(c)ois Boudreau; Nathalie Rivard; Nathalie Perreault

    2012-01-01

    AIM:To investigate the impact of phosphatase and tensin homolog (Pten) in the specification of intestinal enteroendocrine subpopulations.METHODS:Using the Cre/IoxP system,a mouse with conditional intestinal epithelial Pten deficiency was generated.Pten mutant mice and controls were sacrificed and small intestines collected for immunofluorescence and quantitative real-time polymerase chain reaction.Blood was collected on 16 h fasted mice by cardiac puncture.Enzyme-linked immunosorbent assay was used to measure blood circulating ghrelin,somatostatin (SST) and glucose-dependent insulinotropic peptide (GIP) levels.RESULTS:Results show an unexpected dual regulatory role for epithelial Pten signalling in the specification/differentiation of enteroendocrine cell subpopulations in the small intestine.Our data indicate that Pten positively regulates chromogranin A (CgA) expressing subpopulations,including cells expressing secretin,ghrelin,gastrin and cholecystokinin (CCK).In contrast,Pten negatively regulates the enteroendocrine subtype specification of non-expressing CgA cells such as GIP and SST expressing cells.CONCLUSION:The present results demonstrate that Pten signalling favours the enteroendocrine progenitor to specify into cells expressing CgA including those producing CCK,gastrin and ghrelin.

  3. Proliferative and Invasive Effects of Progesterone-Induced Blocking Factor in Human Glioblastoma Cells

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    Hansberg-Pastor, Valeria

    2017-01-01

    Progesterone-induced blocking factor (PIBF) is a progesterone (P4) regulated protein expressed in different types of high proliferative cells including astrocytomas, the most frequent and aggressive brain tumors. It has been shown that PIBF increases the number of human astrocytoma cells. In this work, we evaluated PIBF regulation by P4 and the effects of PIBF on proliferation, migration, and invasion of U87 and U251 cells, both derived from human glioblastomas. PIBF mRNA expression was upregulated by P4 (10 nM) from 12 to 24 h. Glioblastoma cells expressed two PIBF isoforms, 90 and 57 kDa. The content of the shorter isoform was increased by P4 at 24 h, while progesterone receptor antagonist RU486 (10 μM) blocked this effect. PIBF (100 ng/mL) increased the number of U87 cells on days 4 and 5 of treatment and induced cell proliferation on day 4. Wound-healing assays showed that PIBF increased the migration of U87 (12–48 h) and U251 (24 and 48 h) cells. Transwell invasion assays showed that PIBF augmented the number of invasive cells in both cell lines at 24 h. These data suggest that PIBF promotes proliferation, migration, and invasion of human glioblastoma cells. PMID:28168193

  4. Killing of Brain Tumor Cells by Hypoxia-Responsive Element Mediated Expression of BAX

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    Hangjun Ruan

    1999-11-01

    Full Text Available The presence of radioresistant hypoxic cells in human brain tumors limits the overall effectiveness of conventional fractionated radiation therapy. Tumor-specific therapies that target hypoxic cells are clearly needed. We have investigated the expression of suicide genes under hypoxia by a hypoxia-responsive element (HRE, which can be activated through hypoxia-inducible factor-1 (HIF-1. We transfected plasmids containing multiple copies of HIRE into U-87 MG and U-251 MG-NCI human brain tumor cells and tested their ability to induce LacZ gene expression under anoxia. Gene expression under anoxia versus oxia was increased about 12-fold for U-87 MG cells and about fourfold for U-251 MG-NCI cells. At intermediate hypoxic conditions, increased LacZ gene expression in U-87 MG cells was induced by the plasmid that contained three HREs, but not by the plasmid with two HREs. Lastly, when we placed a suicide gene BAX under the control of HREs, cells transfected with the BAX plasmids were preferentially killed through apoptosis under anoxia. Our studies demonstrate that HRE-regulated gene expression is active in brain tumor cells, and that the amount of increased gene expression obtained is dependent on the cell line, the HIRE copy number, and the degree of hypoxia.

  5. Shikonin Inhibits the Migration and Invasion of Human Glioblastoma Cells by Targeting Phosphorylated β-Catenin and Phosphorylated PI3K/Akt: A Potential Mechanism for the Anti-Glioma Efficacy of a Traditional Chinese Herbal Medicine.

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    Zhang, Feng-Ying; Hu, Yi; Que, Zhong-You; Wang, Ping; Liu, Yun-Hui; Wang, Zhen-Hua; Xue, Yi-Xue

    2015-10-09

    Shikonin is an anthraquinone derivative extracted from the root of lithospermum. Shikonin is traditionally used in the treatment of inflammatory and infectious diseases such as hepatitis. Shikonin also inhibits proliferation and induces apoptosis in various tumors. However, the effect of shikonin on gliomas has not been fully elucidated. In the present study, we aimed to investigate the effects of shikonin on the migration and invasion of human glioblastoma cells as well as the underlying mechanisms. U87 and U251 human glioblastoma cells were treated with shikonin at 2.5, 5, and 7.5 μmol/L and cell viability, migration and invasiveness were assessed with CCK8, scratch wound healing, in vitro Transwell migration, and invasion assays. The expression and activity of matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) and the expression of phosphorylated β-catenin (p-β-catenin) and phosphorylated PI3K/Akt were also checked. Results showed that shikonin significantly inhibited the cell proliferation, migration, invasion, and expression of MMP-2 and MMP-9 in U87 and U251 cells. The expression of p-β-catenin showed contrary trends in two cell lines. It was significantly inhibited in U87 cells and promoted in U251 cells. Results in this work indicated that shikonin displayed an inhibitory effect on the migration and invasion of glioma cells by inhibiting the expression and activity of MMP-2 and -9. In addition, shikonin also inhibited the expression of p-PI3K and p-Akt to attenuate cell migration and invasion and MMP-2 and MMP-9 expression in both cell lines, which could be reversed by the PI3K/Akt pathway agonist, insulin-like growth factor-1 (IGF-1).

  6. Shikonin Inhibits the Migration and Invasion of Human Glioblastoma Cells by Targeting Phosphorylated β-Catenin and Phosphorylated PI3K/Akt: A Potential Mechanism for the Anti-Glioma Efficacy of a Traditional Chinese Herbal Medicine

    Directory of Open Access Journals (Sweden)

    Feng-Ying Zhang

    2015-10-01

    Full Text Available Shikonin is an anthraquinone derivative extracted from the root of lithospermum. Shikonin is traditionally used in the treatment of inflammatory and infectious diseases such as hepatitis. Shikonin also inhibits proliferation and induces apoptosis in various tumors. However, the effect of shikonin on gliomas has not been fully elucidated. In the present study, we aimed to investigate the effects of shikonin on the migration and invasion of human glioblastoma cells as well as the underlying mechanisms. U87 and U251 human glioblastoma cells were treated with shikonin at 2.5, 5, and 7.5 μmol/L and cell viability, migration and invasiveness were assessed with CCK8, scratch wound healing, in vitro Transwell migration, and invasion assays. The expression and activity of matrix metalloproteinase-2 (MMP-2 and matrix metalloproteinase-9 (MMP-9 and the expression of phosphorylated β-catenin (p-β-catenin and phosphorylated PI3K/Akt were also checked. Results showed that shikonin significantly inhibited the cell proliferation, migration, invasion, and expression of MMP-2 and MMP-9 in U87 and U251 cells. The expression of p-β-catenin showed contrary trends in two cell lines. It was significantly inhibited in U87 cells and promoted in U251 cells. Results in this work indicated that shikonin displayed an inhibitory effect on the migration and invasion of glioma cells by inhibiting the expression and activity of MMP-2 and -9. In addition, shikonin also inhibited the expression of p-PI3K and p-Akt to attenuate cell migration and invasion and MMP-2 and MMP-9 expression in both cell lines, which could be reversed by the PI3K/Akt pathway agonist, insulin-like growth factor-1 (IGF-1.

  7. Inhibitor of Nicotinamide Phosphoribosyltransferase Sensitizes Glioblastoma Cells to Temozolomide via Activating ROS/JNK Signaling Pathway

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    Jun Feng

    2016-01-01

    Full Text Available Overcoming temozolomide (TMZ resistance is a great challenge in glioblastoma (GBM treatment. Nicotinamide phosphoribosyltransferase (NAMPT is a rate-limiting enzyme in the biosynthesis of nicotinamide adenine dinucleotide and has a crucial role in cancer cell metabolism. In this study, we investigated whether FK866 and CHS828, two specific NAMPT inhibitors, could sensitize GBM cells to TMZ. Low doses of FK866 and CHS828 (5 nM and 10 nM, resp. alone did not significantly decrease cell viability in U251-MG and T98 GBM cells. However, they significantly increased the antitumor action of TMZ in these cells. In U251-MG cells, administration of NAMPT inhibitors increased the TMZ (100 μM-induced apoptosis and LDH release from GBM cells. NAMPT inhibitors remarkably enhanced the activities of caspase-1, caspase-3, and caspase-9. Moreover, NAMPT inhibitors increased reactive oxygen species (ROS production and superoxide anion level but reduced the SOD activity and total antioxidative capacity in GBM cells. Treatment of NAMPT inhibitors increased phosphorylation of c-Jun and JNK. Administration of JNK inhibitor SP600125 or ROS scavenger tocopherol with TMZ and NAMPT inhibitors substantially attenuated the sensitization of NAMPT inhibitor on TMZ antitumor action. Our data indicate a potential value of NAMPT inhibitors in combined use with TMZ for GBM treatment.

  8. Neurokinin-1 receptor directly mediates glioma cell migration by up-regulation of matrix metalloproteinase-2 (MMP-2) and membrane type 1-matrix metalloproteinase (MT1-MMP).

    Science.gov (United States)

    Mou, Lingyun; Kang, Yawei; Zhou, Ying; Zeng, Qian; Song, Hongjing; Wang, Rui

    2013-01-04

    Neurokinin-1 receptor (NK1R) occurs naturally on human glioblastomas. Its activation mediates glioma cell proliferation. However, it is unknown whether NK1R is directly involved in tumor cell migration. In this study, we found human hemokinin-1 (hHK-1), via NK1R, dose-dependently promoted the migration of U-251 and U-87 cells. In addition, we showed that hHK-1 enhanced the activity of MMP-2 and the expression of MMP-2 and MT1-matrix metalloproteinase (MMP), which were responsible for cell migration, because neutralizing the MMPs with antibodies decreased cell migration. The involved mechanisms were then investigated. In U-251, hHK-1 induced significant calcium efflux; phospholipase C inhibitor U-73122 reduced the calcium mobilization, the up-regulation of MMP-2 and MT1-MMP, and the cell migration induced by hHK-1, which meant the migration effect of NK1R was mainly mediated through the G(q)-PLC pathway. We further demonstrated that hHK-1 boosted rapid phosphorylation of ERK, JNK, and Akt; inhibition of ERK and Akt effectively reduced MMP-2 induction by hHK-1. Meanwhile, inhibition of ERK, JNK, and Akt reduced the MT1-MMP induction. hHK-1 stimulated significant phosphorylation of p65 and c-JUN in U-251. Reporter gene assays indicated hHK-1 enhanced both AP-1 and NF-κB activity; inhibition of ERK, JNK, and Akt dose-dependently suppressed the NF-κB activity; only the inhibition of ERK significantly suppressed the AP-1 activity. Treatment with specific inhibitors for AP-1 or NF-κB strongly blocked the MMP up-regulation by hHK-1. Taken together, our data suggested NK1R was a potential regulator of human glioma cell migration by the up-regulation of MMP-2 and MT1-MMP.

  9. Induction of G1 Cell Cycle Arrest in Human Glioma Cells by Salinomycin Through Triggering ROS-Mediated DNA Damage In Vitro and In Vivo.

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    Zhao, Shi-Jun; Wang, Xian-Jun; Wu, Qing-Jian; Liu, Chao; Li, Da-Wei; Fu, Xiao-Ting; Zhang, Hui-Fang; Shao, Lu-Rong; Sun, Jing-Yi; Sun, Bao-Liang; Zhai, Jing; Fan, Cun-Dong

    2016-12-19

    Chemotherapy has always been one of the most effective ways in combating human glioma. However, the high metastatic potential and resistance toward standard chemotherapy severely hindered the chemotherapy outcomes. Hence, searching effective chemotherapy drugs and clarifying its mechanism are of great significance. Salinomycin an antibiotic shows novel anticancer potential against several human tumors, including human glioma, but its mechanism against human glioma cells has not been fully elucidated. In the present study, we demonstrated that salinomycin treatment time- and dose-dependently inhibited U251 and U87 cells growth. Mechanically, salinomycin-induced cell growth inhibition against human glioma was mainly achieved by induction of G1-phase arrest via triggering reactive oxide species (ROS)-mediated DNA damage, as convinced by the activation of histone, p53, p21 and p27. Furthermore, inhibition of ROS accumulation effectively attenuated salinomycin-induced DNA damage and G1 cell cycle arrest, and eventually reversed salinomycin-induced cytotoxicity. Importantly, salinomycin treatment also significantly inhibited the U251 tumor xenograft growth in vivo through triggering DNA damage-mediated cell cycle arrest with involvement of inhibiting cell proliferation and angiogenesis. The results above validated the potential of salinomycin-based chemotherapy against human glioma.

  10. Oxymatrine Inhibits Proliferation and Migration While Inducing Apoptosis in Human Glioblastoma Cells

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    Feili Liu

    2016-01-01

    Full Text Available Oxymatrine (OMT, an alkaloid derived from the traditional Chinese medicine herb Sophora flavescens Aiton, has been shown to exhibit anticancer properties on various types of cancer cells. In this study, we investigate the anticancer properties of OMT on human glioblastoma (GBM cells and evaluate their underlying mechanisms. MTT assays were performed and demonstrated that OMT significantly inhibits the proliferation of GBM cells. Flow cytometry suggested that OMT at a concentration of 10−5 M may induce apoptosis in U251 and A172 cells. Western blot analyses demonstrated a significant increase in the expression of Bax and caspase-3 and a significant decrease in expression of Bcl-2 in both U251 and A172 cells. Additionally, OMT was found by transwell and high-content screening assays to decrease the migratory ability of the evaluated GBM cells. These findings suggest that the antitumor effects of OMT may be the result of inhibition of cell proliferation and migration and the induction of apoptosis by regulating the expression of apoptosis-associated proteins. OMT may represent a novel anticancer therapy for the treatment of GBM.

  11. Omega-3 fatty acid supplementation in cancer therapy. Does eicosapentanoic acid influence the radiosensitivity of tumor cells?

    Energy Technology Data Exchange (ETDEWEB)

    Manda, Katrin; Kriesen, Stephan; Hildebrandt, Guido [Rostock Univ. (Germany). Dept. of Radiotherapy; Fietkau, Rainer; Klautke, Gunther [Univ. Hospital Erlangen, Erlangen (Germany). Dept. of Radiation Oncology

    2011-02-15

    Purpose: The aim of this study was to evaluate whether the omega-3 polyunsaturated fatty acid cis-5,8,11,14,17-eicosapentanoic acid (EPA) can enhance the radiosensitivity of different human tumor cell lines. Materials and Methods: Colon adenocarcinoma cells HT-29, and two glioblastoma multiforme tumor cells T98G and U251 were cultured under standard conditions. Cell growth was observed during administration with different concentrations of EPA, using it as the free fatty acid dissolved in ethanol or bound to bovine serum albumin. To investigate the influence of EPA (free and bound) on radiosensitivity, tumor cells were pretreated 30 minutes or 24 hours prior to irradiation with the fatty acid. Cell survival was measured by colony-forming assays. Results: When combined with irradiation, incubation with EPA was found to result in enhanced radiosensitivity with substantial variation: while there was strong radiosensitization for HT-29 and U251 cells, almost no effect for T98G cells was observed. A marked radiosensitization was clearly dependent on the treatment schedule. Conclusion: The observations suggest that EPA is not only a nutritional adjuvant but also may be a potential candidate to enhance the efficacy of irradiation on human cancer cells. (orig.)

  12. HIF-1α inhibition by siRNA or chetomin in human malignant glioma cells: effects on hypoxic radioresistance and monitoring via CA9 expression

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    Bache Matthias

    2010-11-01

    Full Text Available Abstract Background Hypoxia induces activation of the HIF-1 pathway and is an essential characteristic of malignant gliomas. Hypoxia has been linked to tumor progression, therapy resistance and poor prognosis. However, little is known about the impact of HIF-1α inhibition on radioresistance of malignant glioma. Methods In this study, we investigated the effects of the inhibition of HIF-1α on cell survival and radiosensitivity in U251MG and U343MG glioma cells, using two different strategies. HIF-1α inhibition was achieved by siRNA targeting of HIF-1α or via chetomin, a disruptor of interactions between HIF-1α and p300. The inhibition of the HIF-1 pathway was monitored by quantitative real-time PCR and Western blot analyses of the expression levels of HIF-1α and CA9. CA9 expression was investigated as a potential indicator of the efficacy of HIF-1 inhibition and the resulting radiosensitivity of malignant glioma cell lines was determined by clonogenic assay after irradiation under normoxic (2-10 Gy or hypoxic (2-15 Gy conditions. Results Although siRNA and chetomin show distinct modes of action, both attenuated the hypoxia-induced radioresistance of malignant glioma cell lines U251MG (DMF10: 1.35 and 1.18 and U343MG (DMF10: 1.78 and 1.48. However, siRNA and chetomin showed diverse effects on radiosensitivity under normoxic conditions in U251MG (DMF10: 0.86 and 1.35 and U343MG (DMF10: 1.33 and 1.02 cells. Conclusions Results from this in vitro study suggest that inhibition of HIF-1α is a promising strategy to sensitize human malignant gliomas to radiotherapy and that CA9 could serve as an indicator of effective HIF-1-related radiosensitization.

  13. Antiproliferative activity of Eremanthus crotonoides extracts and centratherin demonstrated in brain tumor cell lines

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    Jonathas F. R. Lobo

    2012-12-01

    Full Text Available The genus Eremanthus is recognized by the predominance of sesquiterpene lactones from the furanoheliangolide type, a class of substances extensively tested against cancer cell lines. Thus, the species E. crotonoides (DC. Sch. Bip., Asteraceae, obtained on "restinga" vegetation was evaluated against U251 and U87-MG glioma cell lines using the MTT colorimetric assay. Dichloromethane fraction was cytotoxic to both glioblastoma multiforme cell lines. We then conducted UPLC-PDA-ESI-MS/MS analysis of the dichloromethane fraction, which allowed the identification of the sesquiterpene lactones centratherin and goyazensolide. The isolation of centratherin was performed using chromatographic techniques and the identification of this substance was confirmed according to NMR data. Cytotoxic activity of centratherin alone was also evaluated against both U251 and U87-MG cells, which showed IC50 values comparable with those obtained for the commercial anticancer drug doxorubicin. All the tested samples showed cytotoxic activity against glioblastoma multiforme cells which suggests that E. crotonoides extracts may be important sources of antiproliferative substances and that the centratherin may serve as prototype for developing new antiglioblastoma drugs.

  14. Down-regulation of ribosomal protein S15A inhibits proliferation of human glioblastoma cells in vivo and in vitro via AKT pathway.

    Science.gov (United States)

    Yao, Yiqun; Liu, Yongjian; Lv, Xiupeng; Dong, Bin; Wang, Feng; Li, Jun; Zhang, Qiuping; Xu, Ruixue; Xu, Yinghui

    2016-04-01

    Ribosomal protein s15a (RPS15A), a highly conserved cytoplasmic protein, promotes mRNA/ribosome interaction in translation. Recent evidence showed that RPS15A is essential for tumor growth. RPS15A expression level was measured in glioblastoma tissue samples and normal brain (NB) tissue samples. RPS15A RNAi stable cell line U87 and U251 was generated by the pLVTHM-GFP lentiviral RNAi expression system. The knockdown efficiency was confirmed by quantitative real-time PCR and western blot. Molecular mechanisms and the effect of RPS15A on cell growth and migration were investigated by using western blot, MTT assay, wound healing assay, transwell migration assay, and tumorigenesis in nude mice. Here, we report that RPS15A is overexpressed in human glioblastoma tumor tissues. RPS15A knockdown inhibits proliferation and migration of glioblastoma cells in vitro. Knocking down RPS15A leads to the level of p-Akt decrease and cell cycle arrested in G0/G1 phase in U87 and U251 cells. Furthermore, the growth of glioblastoma cell-transplanted tumors in nude mice is inhibited by transduction with Lv-shRPS15A. Our findings indicate that RPS15A promotes cell proliferation and migration in glioblastoma for the first time. RPS15A might play a distinct role in glioblastoma and serve as a potential target for therapy.

  15. Efficient inhibition of human telomerase activity by antisense oligonucleotides sensitizes cancer cells to radiotherapy

    Institute of Scientific and Technical Information of China (English)

    Xue-mei JI; Cong-hua XIE; Ming-hao FANG; Fu-xiang ZHOU; Wen-jie ZHANG; Ming-sheng ZHANG; Yun-feng ZHOU

    2006-01-01

    Aim: To investigate the effect of the antisense oligonucleotides (ASODN) specific for human telomerase RNA (hTR) on radio sensitization and proliferation inhibition in human neurogliocytoma cells (U251). Methods: U251 cells were transfected with hTR ASODN or nonspecific oligonucleotides (NSODN). Before and after irradiation of 60Co-γray, telomerase activity was assayed by telomeric repeat amplification protocol (TRAP-PCR-ELISA), and DNA damage and repair were examined by the comet assay. The classical colony assay was used to plot the cell-survival curve, to detect the D0 value. Results: hTR antisense oligonucleotides could downregulate the telomerase activity, increase radiation induced DNA damage and reduce the subsequent repair. Furthermore, it could inhibit the proliferation and decrease the D0 value which demonstrates rising radiosensitivity. However, telomere length was unchanged over a short period of time. Conclusion: These findings suggest that an ASODN-based strategy may be used to develop telomerase inhibitors, which can efficiently sensitize radiotherapy.

  16. Topoisomerase I inhibitors, shikonin and topotecan, inhibit growth and induce apoptosis of glioma cells and glioma stem cells.

    Directory of Open Access Journals (Sweden)

    Feng-Lei Zhang

    Full Text Available Gliomas, the most malignant form of brain tumors, contain a small subpopulation of glioma stem cells (GSCs that are implicated in therapeutic resistance and tumor recurrence. Topoisomerase I inhibitors, shikonin and topotecan, play a crucial role in anti-cancer therapies. After isolated and identified the GSCs from glioma cells successfully, U251, U87, GSCs-U251 and GSCs-U87 cells were administrated with various concentrations of shikonin or topotecan at different time points to seek for the optimal administration concentration and time point. The cell viability, cell cycle and apoptosis were detected using cell counting kit-8 and flow cytometer to observe the inhibitory effects on glioma cells and GSCs. We demonstrated that shikonin and topotecan obviously inhibited proliferation of not only human glioma cells but also GSCs in a dose- and time-dependent manner. According to the IC50 values at 24 h, 2 μmol/L of shikonin and 3 μmol/L of topotecan were selected as the optimal administration concentration. In addition, shikonin and topotecan induced cell cycle arrest in G0/G1 and S phases and promoted apoptosis. The down-regulation of Bcl-2 expression with the activation of caspase 9/3-dependent pathway was involved in the apoptosis process. Therefore, the above results showed that topoisomerase I inhibitors, shikonin and topotecan, inhibited growth and induced apoptosis of GSCs as well as glioma cells, which suggested that they might be the potential anticancer agents targeting gliomas to provide a novel therapeutic strategy.

  17. MicroRNA-218 modulates activities of glioma cells by targeting HMGB1

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    Gu, Jianjun; Xu, Rong; Li, Yaxing; Zhang, Jianhe; Wang, Shousen

    2016-01-01

    To explore the effects of microRNA-218 (miR-218) on glioma cell lines and the related mechanism. U251 and U87 cells were transfected with negative control, miR-218 mimic or miR-218 inhibitor using lipofectamine 2000. The expressions of mRNA and proteins were detected with qRT-PCR and Western blotting. The cell proliferation, apoptosis, migration and invasion were studied using MTT, flow cytometry, Transwell assay and scratch-wound assay, respectively. The targeting effect of HMGB1 by miR-218 was measured with luciferase reporter assay. The results showed that miR-218 was significantly downregulated while HMGB1 was upregulated in both glioma cell lines. Transfection of miR-218 significantly reduced the cell viability and colony formation, increased cell apoptosis and arrested cell in G0/G1 phase. Transfection of miR-218 also decreased the invasion and migration of glioma cells. The expressions of HMGB1, RAGE, cyclin D1 and MMP-9 were downregulated while the expression of caspase-9 was upregulated by miR-218. Silencing HMGB1 increased the expression of RAGE, cyclin D1, MMP-9 but decreased the expression of caspase-9 in U251 and U87 cells. Co-transfection with pcHMGB1 and miR-218 significantly decreased the growth inhibition and increased the apoptosis of glioma cells while these effects were abolished in glioma cells co-transfected with HMGB1 siRNA and miR-218 inhibitor. In addition, co-transfection with pcHMGB1 and miR-218 inhibitor increased the invasiveness of U251 and U87 cells. These findings suggested that miR-218 may negatively regulate HMGB-mediated suppression of RAGE to regulate cell proliferation, apoptosis and invasion, and that intervention of miR-218-HMGB1-RAGE may be useful for developing potential clinical strategies. PMID:27725858

  18. siRNA targeting stathmin inhibits invasion and enhances chemotherapy sensitivity of stem cells derived from glioma cell lines.

    Science.gov (United States)

    Song, Yuwen; Mu, Luyan; Han, Xuezhe; Liu, Xiaoqian; Fu, Songbin

    2014-12-01

    Glioma is one of the most highly angiogenic tumors, and glioma stem cells (GSCs) are responsible for resistance to chemotherapy and radiotherapy, as well as recurrence after operation. Stathmin is substantial for mitosis and plays an important role in proliferation and migration of glioma-derived endothelial cells. However, the relationship between stathmin and GSCs is incompletely understood. Here we isolated GSCs from glioma cell lines U87MG and U251, and then used siRNA targeting stathmin for silencing. We showed that silencing of stathmin suppressed the proliferation, increased the apoptosis rate, and arrested the cell cycle at G2/M phase in GSCs. Silencing of stathmin in GSCs also resulted in inhibited the migration/invasion as well as the capability of vasculogenic mimicry. The susceptibility of GSCs to temozolomide was also enhanced by stathmin silencing. Our findings suggest stathmin as a potential target in GSCs for glioma treatment.

  19. Radiation related basic cancer research : research for radiation induced tumor cell killing

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    Lee, Seung Hoon; Hong, Seok Il; Cho, Kyung Ja; Kim, Byung Gi; Lee, Kee Ho; Nam, Myung Jin

    1999-04-01

    The radioresistant clones was established from human U251 glioblastoma cell line through intermittently exposed to 3 Gy gamma-radiation for six months. Treatment of SNU-16 cells with various doses of radiation, TNF alpha and PMA resulted in a decrease in cell viability. The results prove that cell death of SNU16 is a apoptosis mediated by caspase-3. We have examined the expression of bcl-2 and c-myc in cervical cancer specimens and cervical intraepithelial neoplasia (CIN) to determine the role of coexpression of bcl-3 and c-myc during progression into cervical cancer. The frequent alterations in FHIT expression in many cervical carcinomas and their cell lines suggest that FHIT gene alterations are pla a role in cervical tumorigenesis. According to these correlation between the viability and apoptosis of RD cells, the proper range of the dosage for the investigation of differentiation potency in RD cells was assessed as 1 to 3Gy.

  20. SDF-1/CXCR4 Axis Regulates Cell Cycle Progression and Epithelial-Mesenchymal Transition via Up-regulation of Survivin in Glioblastoma.

    Science.gov (United States)

    Liao, Anyan; Shi, Ranran; Jiang, Yuliang; Tian, Suqing; Li, Panpan; Song, Fuxi; Qu, Yalan; Li, Jinna; Yun, Haiqin; Yang, Xiangshan

    2016-01-01

    Stromal cell-derived factor 1 (SDF-1)/CXCR4 ligand-receptor axis is widely recommended as an attractive target for cancer therapy. Meanwhile, epithelial-mesenchymal transition (EMT) process is linked to disease pathophysiology. As one of inhibitors of apoptosis proteins, survivin is implicated in the onset and development of cancer. In the present study, we tried to determine the cause-effect associations between SDF-1/CXCR4 axis and survivin expression in glioblastoma U-251 cell line. Survivin activation and inhibition were induced with exogenous SDF-1 and survivin small interfering RNA (survivin siRNA), respectively. Western blot was used to detect relevant proteins in SDF-1/CXCR4 axis. Western blot analysis revealed that survivin expression in U-251 increased in a dose- and time-dependent manner in response to SDF-1 treatment. However, the interference with MEK/ERK and PI3K/AKT pathway prohibited SDF-1-induced survivin up-regulation. Importantly, survivin knockdown abrogated cell cycle progression and the expression of snail and N-cadherin, compared with non-transfectants. In conclusion, the present study shows that SDF-1 up-regulates survivin via MEK/ERK and PI3K/AKT pathway, leading to cell cycle progression and EMT occurrence dependent on survivin. The blockade of survivin will allow for the treatment of glioblastoma.

  1. Analysis of target genes induced by IL-13 cytotoxin in human glioblastoma cells.

    Science.gov (United States)

    Han, Jing; Yang, Liming; Puri, Raj K

    2005-03-01

    IL-13 cytotoxin comprised of IL-13 and a mutated form of Pseudomonas exotoxin (fusion protein termed IL-13-PE38QQR) has been shown to inhibit protein synthesis leading to necrotic and apoptotic cell death in glioblastoma cells that express high levels of interleukin-13 receptors (IL-13R). To identify target genes of cell death and other cellular genes with IL-13 receptors in glioblastoma cells, we utilized the cDNA microarrays to analyze global gene expression profiles after IL-13 cytotoxin and IL-13 treatment. IL-13 cytotoxin mediated cytotoxicity to U251 cells in a dose-dependent manner. Hierarchical cluster analysis of differentially expressed genes in U251 glioma cells at different time points after IL-13 cytotoxin treatment showed three major groups, each representing a specific expression pattern. Randomly selected differentially expressed genes from each group were confirmed by RT-PCR analysis. Most down-regulated genes belong to cell adhesion, motility, angiogenesis, DNA repair, and metabolic pathways. While up-regulated genes belong to cell cycle arrest, apoptosis, signaling and various metabolic pathways. Unexpectedly, at early time points, both IL-13 and IL-13 cytotoxin induced several genes belonging to different pathways most notably IL-8, DIO2, END1, and ALDH1A3 indicating that these genes are early response genes and their products may be associated with IL-13R. In addition, IL-13 cytotoxin induced IL-13Ralpha2 mRNA expression during the treatment in glioma cells. Our results indicate that novel cellular genes are involved with IL-13 receptors and that IL-13 cytotoxin induced cell death involves various target genes in human glioblastoma cells. On going studies will determine the role of associated genes and their products in the IL-13R functions in glioma cells.

  2. Effects of Crude Extracts from Medicinal Herbs Rhazya stricta and Zingiber officinale on Growth and Proliferation of Human Brain Cancer Cell Line In Vitro

    Directory of Open Access Journals (Sweden)

    Ayman I. Elkady

    2014-01-01

    Full Text Available Hitherto, limited clinical impact has been achieved in the treatment of glioblastoma (GBMs. Although phytochemicals found in medicinal herbs can provide mankind with new therapeutic remedies, single agent intervention has failed to bring the expected outcome in clinical trials. Therefore, combinations of several agents at once are gaining increasing attractiveness. In the present study, we investigated the effects of crude alkaloid (CAERS and flavonoid (CFEZO extracts prepared from medicinal herbs, Rhazya stricta and Zingiber officinale, respectively, on the growth of human GBM cell line, U251. R. stricta and Z. officinale are traditionally used in folkloric medicine and have antioxidant, anticarcinogenic, and free radical scavenging properties. Combination of CAERS and CFEZO treatments synergistically suppressed proliferation and colony formation and effectively induced morphological and biochemical features of apoptosis in U251 cells. Apoptosis induction was mediated by release of mitochondrial cytochrome c, increased Bax : Bcl-2 ratio, enhanced activities of caspase-3 and -9, and PARP-1 cleavage. CAERS and CFEZO treatments decreased expression levels of nuclear NF-κBp65, survivin, XIAP, and cyclin D1 and increased expression level of p53, p21, and Noxa. These results suggest that combination of CAERS and CFEZO provides a useful foundation for studying and developing novel chemotherapeutic agents for the treatment of GBM.

  3. PROTECTIVE EFFECT OF MELATONIN ON NEURAL CELLS AGAINST THE CYTOTOXICITY OF OXYRADICALS

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective. To investigate the exact mechanism of melatonin to prohibit the apoptosis of neural cells induced by various kinds of cytotoxic agents.Methods. We used the methods of phase contrast microscopy, MTT assay and hoechst dye staining to check this mechanism in SKNSH and U251 cell lines.Results. Both 2mmol/L H2O2 and 0.5 μ mol/L amyloid β- protein (Aβ) induce these two cell lines die via apoptosis. Either melatonin or glutathione can significantly protect both cell lines. The protective effect of 10 μ mol/L melatonin is as same as that of 60 μ mol/L glutathione.Conclusion. Melatonin can partly inhibit the cytotoxicity of H2O2 and Aβ through its role as a free radical scavenger.

  4. Antisense MMP-9 RNA inhibits malignant glioma cell growth in vitro and in vivo

    Institute of Scientific and Technical Information of China (English)

    Cuiyun Sun; Qian Wang; Hongxu Zhou; Shizhu Yu; Alain R.Simard; Chunsheng Kang; Yanyan Li

    2013-01-01

    The matrix-degrading metalloproteinases (MMPs),particularly MMP-9,play important roles in the pathogenesis and development of malignant gliomas.In the present study,the oncogenic role of MMP-9 in malignant glioma cells was investigated via antisense RNA blockade in vitro and in vivo.TJ905 malignant glioma cells were transfected with pcDNA3.0 vector expressing antisense MMP-9 RNA (pcDNA-ASMMP9),which significantly decreased MMP-9 expression,and cell proliferation was assessed.For in vivo studies,U251 cells,a human malignant glioma cell line,were implanted subcutaneously into 4-to 6-week-old BALB/c nude mice.The mice bearing well-established U251 gliomas were treated with intratumoral pcDNA-AS-MMP9-Lipofectamine complex (AS-MMP-9-treated group),subcutaneous injection of endostatin (endostatin-treated group),or both (combined therapy group).Mice treated with pcDNA (empty vector)-Lipofectamine served as the control group.Four or eight weeks later,the volume and weight of tumor,MMP-9 expression,microvessel density and proliferative activity were assayed.We demonstrate that pcDNA-AS-MMP9 significantly decreased MMP-9 expression and inhibited glioma cell proliferation.Volume and weight of tumor,MMP-9 expression,microvessel density and proliferative activity in the antisense-MMP-9-treated and therapeutic alliance groups were significantly lower than those in the control group.The results suggest that MMP-9 not only promotes malignant glioma cell invasiveness,but also affects tumor cell proliferation.Blocking the expression of MMP-9 with antisense RNA substantially suppresses the malignant phenotype of glioma cells,and thus can be used as an effective therapeutic strategy for malignant gliomas.

  5. Exogenous p16 gene therapy combined with X-ray irradiation suppresses the growth of human glioma cells

    Institute of Scientific and Technical Information of China (English)

    Hongbing Ma; Zhengli Di; Minghua Bai; Hongtao Ren; Zongfang Li

    2011-01-01

    In this study, we infected human glioma U251 cells with a replication-defective recombinant adeno-virus carrying the p16 gene. This adenovirus constructed was able to transfect exogenous p16 into the human glioma cells efficiently, and direct a high level of p16 protein expression. Tumor-inhibition experiments demonstrated that treatment with the adenovirus-p16 significantly inhibited the growth of glioma cells in vitro as well as the in vivo development of tumors in nude mice bearing a brain glioma. The combination of adenovirus-p16 gene treatment and X-ray irradiation resulted in a greater inhibition of tumor growth. Adenovirus-mediated p16 gene therapy conferred a significant antitumor effect against human glioma cells both in vitro and in vivo, and that there was a synergistic effect when X-ray irradiation was also used.

  6. Overexpression of miR-100 inhibits cell proliferation, migration, and chemosensitivity in human glioblastoma through FGFR3

    Directory of Open Access Journals (Sweden)

    Luan YX

    2015-11-01

    Full Text Available Yongxin Luan,1 Shuyan Zhang,1 Ling Zuo,2 Lixiang Zhou1 1Department of Neurosurgery, First Bethune Hospital of Jilin University, 2Department of Ophthalmology, Second Bethune Hospital of Jilin University, Changchun, People’s Republic of China Background: Glioblastoma multiforme is one of the most deadly forms of brain cancer. We investigated the regulatory effects of microRNA-100 (miR-100 on cell proliferation, migration, and chemosensitivity in human glioblastoma. Methods: miR-100 expression was assessed by quantitative real-time polymerase chain reaction in both glioblastoma cells and human tumors. Lentiviruses of miR-100 mimics and inhibitors were transfected into U251 and T98G cells. The regulatory effects of either overexpressing or downregulating miR-100 on glioblastoma were evaluated by a viability assay, growth assay, migration assay, chemosensitivity assay, and an in vivo tumor transplantation assay. Expression of fibroblast growth factor receptor 3 (FGFR3, the bioinformatically predicted target of miR-100, was examined by Western blot in glioblastoma. FGFR3 was then ectopically overexpressed in U251 and T98G cells, and its effects on miR-100-mediated cancer regulation were evaluated by growth, migration, and chemosensitivity assays. Results: MiR-100 was markedly downregulated in both glioblastoma cell lines and human tumors. Overexpressing miR-100 through lentiviral transfection in U251 and T98G cells significantly inhibited cancer growth (both in vitro and in vivo and migration and increased chemosensitivity to cisplatin and 1, 3-bis (2-chloroethyl-l-nitrosourea, whereas downregulation of miR-100 had no effects on development of cancer. FGFR3 was directly regulated by miR-100 in glioblastoma. Ectopically overexpressing FGFR3 was able to ameliorate the anticancer effects of upregulation of miR-100 on glioblastoma growth, migration, and chemosensitivity. Conclusion: MiR-100 was generally downregulated in glioblastoma. Overexpressing mi

  7. MicroRNA-7 regulates glioblastoma cell invasion via targeting focal adhesion kinase expression

    Institute of Scientific and Technical Information of China (English)

    WU De-gang; WANG Xi-rui; YOU Yong-ping; LIU Ning; WANG Ying-yi; FAN Li-gang; LUO Hui; HAN Bin; SUN Li-hua; WANG Xie-feng; ZHANG Jun-xia; CAO Lei

    2011-01-01

    Background Invasion growth is the most characteristic biological phenotype of glioblastoma,but the molecular mechanism in glioma cell invasion is poorly understood.Recent data have showed that microRNA plays an essential role in tumor invasion.Our study aimed to explore the mechanism of miR-7 involved in the control of glioblastoma cell invasion.Methods Glioma cell invasion was evaluated by transwell and scratch assays after up-regulation of miR-7 using miR-7 mimics in U87 and U251 cells.Luciferase reporter assay was used to determine focal adhesion kinase (FAK) as a target of miR-7.The levels of miR-7,matrix metalloproteinases (MMP)-2 and MMP-9 mRNA were detected by PCR assay,and the levels of FAK,MMP-2,MMP-9,total and phosphorylation serine/threonine kinase (AKT),and extracellular signal-regulated kinase (ERK) 1/2 were measured by Western blotting analysis.Results Over-expression of miR-7 inhibited the invasion and migration activity of U87 and U251 cells.And up-regulation of miR-7 reduced FAK protein expression,Further,luciferase reporter assay showed that miR-7 modulated FAK expression directly by binding 3'UTR of FAK mRNA.In addition,miR-7 repressed p-ERK1/2 and p-AKT level,MMP-2 and MMP-9 expression.Finally,the inverse relationship between FAK and miR-7 expression was certificated in human glioma tissues.Conclusion To our knowledge,these data indicate for the first time that miR-7 directly regulates cell invasion by targeting FAK in glioblastoma and that miR-7 could be a potential therapeutic target for glioblastoma intervention.

  8. Adenoviral-mediated delivery of herpes simplex virus thymidine kinase gene controlled by Cfos promoter confers cytotoxic effect on human glioma cells%腺病毒介导的HSV-TK/GCV系统在Cfos启动子调控下对胶质瘤细胞的杀伤作用

    Institute of Scientific and Technical Information of China (English)

    王浩; 潘建青; 胡继良; 冯诣; 宋伟健; 罗杰; 刘欣民; 魏强国; 洪全球

    2015-01-01

    目的 构建人Cfos启动子调控的单纯疱疹病毒(HSV)-胸苷激酶(TK)自杀基因重组腺病毒载体,观察其介导的HSV-TK/更昔洛韦(GCV)系统对胶质瘤细胞的杀伤作用. 方法 构建重组腺病毒载体Ad-Cfos-TK-IRES-hr绿色荧光蛋白(GFP)、Ad-CMV-TK-IRES-hrGFP,转染至HEK293细胞获得重组腺病毒Ad-Cfos-TK-IRES-hrGFP、Ad-CMV-TK-IRES-hrGFP,荧光计数法检测病毒滴度;将病毒感染U251、U87细胞,荧光显微镜下观察GFP的表达.将病毒感染U251、U87细胞,24 h后加入1000、100、10、1、0.1、0.01、0μmol/L GCV作用48 h,CCK-8法检测各组细胞抑制率. 结果 成功构建重组腺病毒载体pDC315-CMV-TK-IRES-hrGFP、pDC315-CFOS-TK-IRES-hrGFP.荧光计数法检测显示2种腺病毒滴度均达1×1010 PFU/mL.在病毒感染复数(MOI)为100、GCV浓度为1、10、100、1000 μmol/L时,转染Ad-Cfos-TK-IRES-hrGFP组U251细胞抑制率分别为(24.18±6.01)%、(30.39±9.67)%、(57.07±9.29)%、(94.50±3.48)%,转染Ad-Cfos-TK-IRES-hrGFP组U87细胞细胞抑制率分别为(9.78±2.24)%、(86.33±5.06)%、(98.48±0.79)%、(98.76±0.93)%. 结论 腺病毒介导的HSV-TK/GCV系统在Cfos启动子调控下在体外可以有效杀伤胶质瘤细胞.%Objective To construct recombinant adenovirus vectors containing herpes simple virus thymidine kinase (HSV-TK) controlled by human Cfos promoter and cytomegalovirus (CMV) promoter and observe the expression of adenovirus in human glioma U251 cells and their specific cytotoxic effect on U251 cells in combination with ganciclovir (GCV) in vitro.Methods Two recombinant adenovirus vectors containing herpes simplex virus thymidine kinase gene controlled by human Cfos promoter and CMV promoter were constructed (Ad-Cfos-TK-IRES-hr green fluorescent protein [GFP] and Ad-CMV-TK-IRES-hrGFP),respectively.For packaging virus,two adenovirus vectors were transfected into HEK293 cells.Ad-CMV-TK-IRES-hrGFP and Ad-Cfos-TK-IRES-hrGFP were collected,purified and

  9. Degradable Organically-Derivatized Polyoxometalate with Enhanced Activity against Glioblastoma Cell Line

    Science.gov (United States)

    She, Shan; Bian, Shengtai; Huo, Ruichao; Chen, Kun; Huang, Zehuan; Zhang, Jiangwei; Hao, Jian; Wei, Yongge

    2016-09-01

    High efficacy and low toxicity are critical for cancer treatment. Polyoxometalates (POMs) have been reported as potential candidates for cancer therapy. On accounts of the slow clearance of POMs, leading to long-term toxicity, the clinical application of POMs in cancer treatment is restricted. To address this problem, a degradable organoimido derivative of hexamolybdate is developed by modifying it with a cleavable organic group, leading to its degradation. Of note, this derivative exhibits favourable pharmacodynamics towards human malignant glioma cell (U251), the ability to penetrate across blood brain barrier and low toxicity towards rat pheochromocytoma cell (PC12). This line of research develops an effective POM-based agent for glioblastoma inhibition and will pave a new way to construct degradable anticancer agents for clinical cancer therapy.

  10. 超短期低剂量伽玛刀照射对胶质瘤细胞侵袭性的影响%Effect of ultra short-term low-dose irradiation on invasive properties of glioma cells: an in vitro study

    Institute of Scientific and Technical Information of China (English)

    林益光; 刘晓民; 张志远; 李彦和; 刘东; 王国开; 徐德生

    2014-01-01

    Objective To evaluate the effect of ultra short-term low-dose gamma knife radiation on invasive properties of glioma cells at the genetic level.Methods Malignant glioma cell lines U87 and U251 were treated with gamma knife radiation,respectively,with a marginal doses of 0,4,6,8 and 10 Gy (all to the 80% isodose line).Real time-PCR was used to measure the mRNA expressions of AKT-1,AKT-2,β-catenin and TCF-4 at 30 min after radiation.Results The expressions of AKT-1,AKT-2,β-catenin,TCF-4 in glioma cell lines after low-dose gamma knife radiation with a marginal dose of 6-8 Gy were significantly increased as compared with those after 0 Gy (P<0.05); reduced expressions ofAKT-1,AKT-2,β-catenin and TCF-4 after a marginal dose of 10 Gy were found as compared with those after 0 Gy (P<0.05); the β-catenin and AKT-1 mRNA expressions in U87 cells and TCF-4,AKT-1 and AKT-2 mRNA expressions in U251 cells enjoyed the most obvious increase at a marginal dose of 6 Gy; the TCF-4 and AKT-2 mRNA expressions in U87 cells and β-catenin mRNA expression in U251 cells enjoyed the most obvious increase at a marginal dose of 8 Gy.Conclusion Low-dose gamma knife radiation (6-8 Gy) could increase the β-catenin,TCF-4,AKT-1 and AKT-2 expressions,while high dose (10 Gy) could inhibit these effects in a short time period of 30 min.%目的 从基因水平验证低剂量伽玛刀照射在超短期内对胶质瘤细胞侵袭性的影响.方法 以80%等剂量线包绕U87、U251细胞系,分别以4、6、8、10Gy边缘剂量行伽玛刀照射30min,以未照射的细胞作为对照组.应用RT-PCR检测细胞β-链蛋白(β-catenin)、T细胞因子4(TCF-4)、蛋白激酶B(AKT)-1、AKT-2 mRNA的表达. 结果 与对照组比较,U87、U251细胞β-catenin、TCF-4、AKT-1和U87细胞AKT-2 mRNA的表达在4、6、8Gy伽玛刀照射后明显上调,10Gy照射后下调;U251细胞AKT-2 mRNA的表达在4、6Gy伽玛刀照射后明显上调,8、10 Gy照射后下调,差异均有统计学意义(P<0

  11. Enhanced MGMT expression contributes to temozolomide resistance in glioma stem-like cells

    Institute of Scientific and Technical Information of China (English)

    Zhi-Kun Qiu; Dong Shen; Yin-Sheng Chen; Qun-Ying Yang; Cheng-Cheng Guo; Bing-Hong Feng; Zhong-Ping Chen

    2014-01-01

    O6-methylguanine DNA methyltransferase (MGMT) can remove DNA alkylation adducts, thereby repairing damaged DNA and contributing to the drug resistance of gliomas to alkylating agents. In addition, glioma stem-like cells (GSCs) have been demonstrated to be involved in the recurrence and treatment resistance of gliomas. In this study, we aimed to investigate MGMT expression and regulatory mechanisms in GSCs and the association of MGMT with temozolomide (TMZ) sensitivity. GSCs were enriched from one MGMT-positive cellline (SF-767) and 7 MGMT-negative celllines (U251, SKMG-4, SKMG-1, SF295, U87, MGR1, and MGR2) through serum-free clone culture. GSCs from the U251G, SKMG-4G, SF295G, and SKMG-1G cell lines became MGMT-positive, but those from the U87G, MGR1G, and MGR2G cell lines remained MGMT-negative. However, al the GSCs and their parental glioma celllines were positive for nuclear factor-κB (NF-κB). In addition, GSCs were more resistant to TMZ than their parental glioma cell lines (P 0.05). When we treated the MGMT-positive GSCs with TMZ plus MG-132 (an NF-κB inhibitor), the antitumor activity was significantly enhanced compared to that of GSCs treated with TMZ alone (P < 0.05). Furthermore, we found that MGMT expression decreased through the down-regulation of NF-κB expression by MG-132. Our results show that MG-132 may inhibit NF-κB expression and further decrease MGMT expression, resulting in a synergistic effect on MGMT-positive GSCs. These results indicate that enhanced MGMT expression contributes to TMZ resistance in MGMT-positive GSCs.

  12. β3GnT8 plays an important role in CD147 signal transduction as an upstream modulator of MMP production in tumor cells.

    Science.gov (United States)

    Jiang, Zhi; Hu, Shuijun; Hua, Dong; Ni, Jianlong; Xu, Lan; Ge, Yan; Zhou, Yinghui; Cheng, Zhihong; Wu, Shiliang

    2014-09-01

    Aberrant carbohydration by related glycosyl-transferases plays an important role in the progression of cancer. This study focused on the ablity of β-1,3-N-acetyl-glucosaminyltransferase-8 (β3GnT8) to regulate MMP-2 expression through regulation of the CD147 signal transduction pathway in cancer cells. β3GnT8 catalyzes and then extends a polylactosamine chain specifically on β1-6-branched tetraantennary N-glycans. CD147 is a major carrier of β1-6-branched polylactosamine sugars on tumor cells, and the high glycoform of CD147 (HG-CD147) induces matrix metalloproteinase (MMP) production. In the present study, we analyzed β3GnT8 mRNA expression in 6 cancer cell lines (MCF-7, M231, LN229, U87, SGC-7901 and U251). We found that β3GnT8 expression in the LN229, SGC-7901 and U251 cell lines was higher than that in the other cell lines. Therefore, we established β3GnT8-knockdown cell lines derived from the LN229 and SGC-7901 cell lines to examine the level of polylactosamine and CD147 N-glycosylation. In addition, tunicamycin is widely used as an inhibitor of N-linked glycosylation. Hence, various concentrations of tunicamycin were used to treat the cells in order to study its influence on CD147 N-glycosylation and MMP-2 expression. In conclusion, we found that β3GnT8 regulated the level of N-glycans on CD147 and that N-glycosylation of CD147 has an important effect on MMP-2 expression. Our findings suggest that β3GnT8 affects the signal transduction pathway of MMP-2 by altering the N-glycan structure of CD147.

  13. Influence of long noncoding RNA HOTAIR on human glioma cell metabolism and growth%长链非编码RNA HOTAIR对人胶质瘤细胞代谢和生长的影响

    Institute of Scientific and Technical Information of China (English)

    魏文金; 韩东风; 李海林; 张军霞; 张雅旋; 胡奇; 李文涛; 俞天赋; 尤永平

    2015-01-01

    目的 探讨长链非编码RNA HOX转录反义RNA (HOX transcript antisense RNA,HOTAIR)对人脑胶质瘤细胞代谢和生长的影响.方法 采用荧光标记的小干扰HOTAIR (si-HOTAIR)转染胶质瘤U87和U251细胞株,通过实时定量荧光聚合酶链式反应(RT-PCR)检测HOTAIR在胶质瘤细胞中的表达水平;利用CCK8实验和克隆形成实验检测细胞的生长变化;采用海马生物公司糖酵解应激实验和线粒体应激实验试剂盒检测细胞有氧糖酵解和线粒体功能.通过Western blot检测有氧糖酵解相关酶[包括葡萄糖-6-磷酸异构酶(GPI)、丙酮酸激酶M2(PKM2)及乳酸脱氢酶A(LDHA)]的表达水平.结果 荧光显微镜下观察U87和U251细胞中si-HOTAIR转染效率均>90%.与阴性对照(NC)组比较,si-HOTAIR组细胞中HOTAIR的表达均明显下调(P<0.01);si-HOTAIR组U87和U251胶质瘤细胞的增殖能力和克隆形成能力明显低于NC组(P<0.01);下调HOTAIR后,胶质瘤细胞有氧糖酵解能力减弱,表现为基础糖酵解水平降低(P<0.05)、最大糖酵解能力减弱(P<0.01)及糖酵解剩储备量下降(P<0.01);si-HOTAIR组GPI、PKM2和LDHA表达水平较NC组降低(P<0.01).下调HOTAIR后,胶质瘤细胞线粒体功能受损,与NC组比较,表现为基础呼吸水平下降(其中U87细胞P<0.01)、线粒体偶联效率降低及剩余呼吸能力减弱(U87和U251组均P<0.05).结论 下调HOTAIR表达可以使人胶质瘤细胞糖酵解能力和线粒体功能受损,同时影响胶质瘤细胞的生长能力.%Objective To investigate the influence of long noncoding RNA HOX transcript antisense RNA (HOTAIR) on human glioma cell metabolism and growth.Methods The fluorescently labeled small interfering (si-HOTAIR) was used to transfect glioma U87 and U251 cell lines.The real-time polymerase chain reaction (RT-PCR) was used to detect the expression level of HOTAIR in glioma cells.CCK8 test and colony formation assay were used to detect the growth changes of

  14. Steroids from the leaves of Chinese Melia azedarach and their cytotoxic effects on human cancer cell lines.

    Science.gov (United States)

    Wu, Shi-Biao; Ji, Yan-Ping; Zhu, Jing-Jing; Zhao, Yun; Xia, Gang; Hu, Ying-He; Hu, Jin-Feng

    2009-09-01

    Three new (1-3) and several known (4-6) steroids were isolated from the leaves of Chinese Melia azedarach. The structures of the new compounds were elucidated by means of spectroscopic methods including 2D NMR techniques and mass spectrometry to be (20S)-5,24(28)-ergostadiene-3beta,7alpha,16beta,20-tetrol (1), (20S)-5-ergostene-3beta,7alpha,16beta,20-tetrol (2), and 2alpha,3beta-dihydro-5-pregnen-16-one (3). The cytotoxicities of the isolated compounds against three human cancer cell lines (A549, H460, U251) were evaluated; only compounds 1, 2, and (20S)-5-stigmastene-3beta,7alpha,20-triol (4) were found to show significant cyctotoxic effects with IC(50)s from 12.0 to 30.1 microg/mL.

  15. 染料木黄酮抑制由单纯疱疹病毒1型感染导致的人胶质瘤细胞增殖和凋亡异常%Inhibitory effects of Genistein on abnormal changes of proliferation and apoptosis caused by herpes simplex virus-1 infectiom in human glioma cell

    Institute of Scientific and Technical Information of China (English)

    王倩; 李玲; 王斌; 于向民; 宋旭霞; 钱冬萌; 侯云; 姜光域; 胡明

    2011-01-01

    目的 染料木黄酮(Genistein,GST)已被证实具有抗广谱病毒的作用,但有关其抑制单纯疱疹病毒Ⅰ型(herpes simplex virus-1,HSV-1)感染人星形胶质细胞的研究鲜有报道.研究GST对由HSV感染所致人胶质瘤细胞(U251)增殖和凋亡异常的抑制作用.方法 设立GST组、GST+HSV-1组、HSV-1组和对照组,以感染复数(multiplicity of infection,MOI)为5的HSV-1感染U251细胞,通过噻唑蓝(MTT)法、流式细胞术和RT-PCR检测GST对HSV-1感染致U251细胞增殖和凋亡异常的抑制作用.结果 ①MTT法显示不同处理组之间的差别具有高度统计学意义(P<0.05),并有非常明显的时间效应(P<0.05).其中30μg/ml GST组和HSV-1组MTT值低于对照组(P<0.05) ;15μg/ml GST+HSV-1组MTT均值高于HSV-1组均值(P<0.05),3.75和30μg/ml GST+HSV-1组MTT值均低于HSV-1组(P<0.05).②形态学观察HSV-1组细胞感染12h后出现融合,36h后出现细胞病变效应,15μg/ml GST+HSV-1组细胞感染24h后开始出现少量融合,36h后融合增多,但大部分细胞为正常形态;流式细胞术显示,15μg/ml GST+HSV-1组凋亡率低于HSV-1组(P<0.05 ).③RT-PCR检测显示HSV-1组感染6h后开始检测到gD基因的表达;15μg/ml GST+HSV-1组在感染12h内gD基因表达受到抑制,24h后gD基因才开始表达.结论 15μg/ml浓度的GST能抑制HSV-1感染所致细胞增殖和凋亡的异常,同时抑制病毒gD基因的表达.%Objective Though Genestein exerts antiviral properties against a wide range of viruses , its inhibitory effects on HSV-1 infected human astrocytes has received little attention. We aimed to investigate the inhibitorv effects of Genistein( GST) on abnormal changes of proliferation and apoptosis caused by H5V-1 infection in Human Glioma Cell ( U251 ) . Methods U251 cells were infected by HSV-1 at a multiplicity of infection of 5 while GST group,CST + HSV-1 group, HSV-1 group and control group were set up. MTT assay, cell apoptosis and RT-PCR were chosen

  16. Boron neutron capture therapy induces apoptosis of glioma cells through Bcl-2/Bax

    Directory of Open Access Journals (Sweden)

    Mao Xinggang

    2010-12-01

    Full Text Available Abstract Background Boron neutron capture therapy (BNCT is an alternative treatment modality for patients with glioma. The aim of this study was to determine whether induction of apoptosis contributes to the main therapeutic efficacy of BNCT and to compare the relative biological effect (RBE of BNCT, γ-ray and reactor neutron irradiation. Methods The neutron beam was obtained from the Xi'an Pulsed Reactor (XAPR and γ-rays were obtained from [60Co] γ source of the Fourth Military Medical University (FMMU in China. Human glioma cells (the U87, U251, and SHG44 cell lines were irradiated by neutron beams at the XAPR or [60Co] γ-rays at the FMMU with different protocols: Group A included control nonirradiated cells; Group B included cells treated with 4 Gy of [60Co] γ-rays; Group C included cells treated with 8 Gy of [60Co] γ-rays; Group D included cells treated with 4 Gy BPA (p-borono-phenylalanine-BNCT; Group E included cells treated with 8 Gy BPA-BNCT; Group F included cells irradiated in the reactor for the same treatment period as used for Group D; Group G included cells irradiated in the reactor for the same treatment period as used for Group E; Group H included cells irradiated with 4 Gy in the reactor; and Group I included cells irradiated with 8 Gy in the reactor. Cell survival was determined using the 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium (MTT cytotoxicity assay. The morphology of cells was detected by Hoechst33342 staining and transmission electron microscope (TEM. The apoptosis rate was detected by flow cytometer (FCM. The level of Bcl-2 and Bax protein was measured by western blot analysis. Results Proliferation of U87, U251, and SHG44 cells was much more strongly inhibited by BPA-BNCT than by irradiation with [60Co] γ-rays (P 60Co] γ-rays (P P Conclusions Compared with ��-ray and reactor neutron irradiation, a higher RBE can be achieved upon treatment of glioma cells with BNCT. Glioma cell apoptosis induced by

  17. Relationship between Golgi apparatus and cell migration direction in vivo and in vitro%高尔基体与细胞运动方向关系的体内外实验研究

    Institute of Scientific and Technical Information of China (English)

    刘彬; 刘志峰; 任炳成; 陈聪; 于圣平; 张斌; 明浩朗; 王垒垒; 赵恺

    2013-01-01

    目的 观察高尔基体与细胞运动方向的关系,探讨高尔基体作为细胞运动方向指示的可行性及其在研究细胞迁移运动方面的生物学意义.方法 选择大鼠C6胶质瘤细胞、人脑U251和SNB19胶质瘤细胞,通过细胞免疫荧光染色观察细胞迁移实验中高尔基体与细胞运动方向的关系,计数高尔基体朝向划痕空白区的细胞所占的百分比;鬼笔环肽细胞骨架染色,观察高尔基体与细胞运动伪足的位置关系;免疫组化染色观大鼠脑胶质瘤组织标本和人脑胶质瘤组织标本中坏死区周围细胞高尔基体的定位与细胞运动方向的关系,计数高尔基体背离坏死区的细胞所占百分比.结果 细胞迁移实验中,位于划痕两侧的绝大多数C6细胞(83%±6%)、U251细胞(80%±7%)、SNB19细胞(82%±6%)的高尔基体朝向划痕空白侧;鬼笔环肽细胞骨架染色显示U251细胞和SNB19细胞中高尔基体的定位方向与细胞的伪足伸展方向一致.免疫组化染色显示,肿瘤组织标本中坏死区周围肿瘤细胞的高尔基体多数(鼠脑80%±7%;人脑82%±6%)背向坏死侧.结论 无论在体内还是在体外环境中,细胞高尔基体的定位方向对于判断细胞的迁移运动方向都具有参考意义,从而为在体研究肿瘤细胞侵袭的生物学行为和抗迁移治疗疗效的观察提供了有力的观测指标.%Objective To explore the relationship between Golgi apparatus and the direction of tumor cell migration in vivo and in vitro.Methods Cell migration assays were conducted with rat C6 glioma cells,human U251 and SNB19 glioma cells respectively.Then immunofluorescence was used to detect the position of Golgi apparatus in migrating cells.The percentage of cells with Golgi apparatus facing towards wound edge was calculated.Cell pseudopodium was stained with TRITC-phalloidin and the relationship between Golgi apparatus and pseudopodium detected

  18. 微环境乏氧通过肿瘤干细胞途径对脑胶质瘤细胞放射敏感性的影响%Effect of microenviroment hypoxia on glioma cells radiosensitivity through cancer stem cell pathway

    Institute of Scientific and Technical Information of China (English)

    童流妹; 冯丽波; 陆雪官; 陈列松; 郭信伟; 田野

    2010-01-01

    目的 探讨微环境乏氧是否能通过肿瘤干细胞途径引起脑胶质瘤放射敏感性的改变以及可能的相关机制.方法 选择脑胶质瘤SHG44和U251细胞株分别在常氧(20%0_2)、乏氧(1%0_2)12和24 h的条件下培养后,应用流式细胞仪检测CD133表达阳性细胞的比例,细胞克隆形成实验绘制细胞存活曲线以观察其放射敏感性,采用Western blotting方法测定基因HIF-la及其下游基因Notch 1蛋白的表达水平.结果 与常氧培养条件比,SHG44和U251细胞乏氧12和24 h后CD133阳性表达比例明显升高;SF_2(2 Gy照射时的存活分数)均升高.在乏氧12和24 h培养时,SHG44细胞株的氧增强比的值分别为1.54和1.38.而U251细胞株则分别为1.44和1.23,提示在乏氧培养时细胞的放射敏感性下降;与常氧培养条件比,乏氧时HIF-la和Notch 1的蛋白表达水平均明显升高.结论 微环境乏氧能通过提高肿瘤干细胞的比例而降低脑胶质瘤细胞的放射敏感性,其可能的作用信号途径为HIF-la-Notch 1.%Objective To investigate the effect of microenviroment hypoxia on glioma cells radiosensitivity through cancer stem pathway,and to explore the related mechanism.Methods Glioma eell lines SHG44 and U251 were cultured in normoxia (20%0_2) or continuous hypoxia (1%0_2)for 12 and 24 h.The fraction of glioma ceils with positive expression of CD133 was assayed by flow cytometry.The radiosensitivity of glioma cells was determined by clonogenic cell assay.Western blotting was used to investigate the expressions of HIF-la and its downstream gene Notch 1.Resuits The fraction of glioma cells with positive expression of CD133 was higher after hypoxic culture for 12 and 24 h than that of the corresponding cells cultured in normoxia.Compared to the cells cultured in normoxia,SF_2(survival fraction at 2 Gy)were enhanced significantly in SHG44 and U251 cells cultured in hypoxia for 12 and 24 h.The OER (oxygen-enhancement ratio) of SHG44 cells in

  19. Truncated forms of BNIP3 act as dominant negatives inhibiting hypoxia-induced cell death

    Science.gov (United States)

    Bristow, Nicolle; Burton, Teralee R; Henson, Elizabeth S; Ong-Justiniano, Coleen; Brown, Michelle; Gibson, Spencer B

    2011-01-01

    BNIP3 (Bcl-2/adenovirus E1B Ninteen Kilodalton Interacting Protein) is a pro-cell death member of the Bcl-2 family of proteins. Its expression is induced by the transcription factor Hypoxia Inducible Factor-1 (HIF-1) under conditions of low oxygen (hypoxia) and is found over expressed in hypoxic regions of many tumors. When over expressed, BNIP3 induces cell death through induction of mitochondrial dysfunction that is dependant on the presence of BNIP3’s TM domain. Herein, we have determined that the SkOv3 ovarian cancer cell line expresses a truncated BNIP3 protein, which results in the elimination of the transmembrane domain. Truncation that eliminates all four domains of BNIP3 protein also inhibits hypoxia-induced cell death in SkOv3, HEK293, U251 and MCF-7 cells. Three different mutations in a BNIP3 expression vector that lead to a truncated BNIP3 protein, lacking TM domain only, or lacking CD, BH3, and TM domains resulted in inhibition of hypoxia-induced cell death when transfected into HEK293 cells. We found that truncated BNIP3 failed to associate with the mitochondria and the truncated BNIP3 lacking all four domains can bind to wild type BNIP3. Taken together, truncation of BNIP3 could be a novel mechanism for cancer cells to avoid hypoxia-induced cell death mediated by BNIP3 over expression. PMID:21138765

  20. The effects of CD147 on the cell proliferation, apoptosis, invasion, and angiogenesis in glioma.

    Science.gov (United States)

    Yin, Haoyuan; Shao, Ying; Chen, Xuan

    2017-01-01

    To analyze the effects of extracellular matrix metalloproteinase inducer (CD147) on glioma proliferation, apoptosis, invasion, and angiogenesis. Tissue samples were obtained from 101 glioma cases while normal brain tissues were obtained from 30 brain injury cases. Immunohistochemical assay was performed to detect the expressions of CD147, CD34, and VEGF in tissue samples. QRT-PCR was performed to detect the relative expression of CD147 mRNA in human glioma cell lines. CD147 siRNA was transfected into glioma cell line U251. Cell proliferation, apoptosis, invasion, and angiogenesis were tested by MTT, flow cytometry, Transwell assay, and vasculogenic mimicry assay, respectively. Expressions of relative proteins were analyzed with western blot. CD147 was positively expressed with the percentage of 0, 37.5, 44.8, 67.9, and 85.7 % in normal tissues and glioma tissues with WHO grades I-IV, respectively, and the scores of MVDand VEGF were associated with the expression of CD147. CD147 was significantly upregulated in the human glioma cell lines (P CD147 suppressed cell proliferation, blocked cell cycle, induced apoptosis, inhibited cell invasion and angiogenesis in glioma cells in vitro. The expression of CD147 was significantly associated with WHO tumor grade and angiogenesis; silencing of CD147 contributed to inhibition of glioma proliferation, invasion, and angiogenesis. Our study provided firm evidence that CD 147 is a potential glioma target for anti-angiogenic therapies.

  1. Targeting therapeutic effect of radioiodine-labeled anti-EGFR binding nanoparticles on glioblastoma cells%131I标记抗表皮生长因子受体抗体靶向性纳米载体治疗胶质母细胞瘤的可行性实验研究

    Institute of Scientific and Technical Information of China (English)

    李承霞; 李玮; 张富海; 贾强; 李宁; 常津; 季艳会; 谭建

    2016-01-01

    目的 构建131I标记抗表皮生长因子受体抗体(antiEGFR)靶向性的纳米载体,探讨其在细胞水平和动物体内用于胶质瘤治疗的可行性.方法 制备放射性碘(131I)标记的antiEGFR靶向性的纳米载体牛血清白蛋白聚己内酯复合物131 I-antiEGFR-BSA-PCL.用共聚焦显微镜观察纳米载体能够与肿瘤细胞结合情况,用MTT法检测纳米载体的细胞毒性作用,摄碘率实验检测肿瘤细胞对放射性纳米载体的摄取.制备裸鼠种植瘤模型,通过瘤体内注射给药,观察裸鼠种植瘤的体积变化,通过SPECT显像观察药物在裸鼠体内的停留情况,并分析纳米载体在裸鼠体内的分布情况.结果 成功地制备了BSA-PCL及antiEGFR-BSA-PCL纳米载体.与BSA-PCL相比,antiEGFR-BSA-PCL 更容易与肿瘤细胞结合.当放射性纳米载体的放射性活度达到0.925 MBq时,U251和U87细胞的生长抑制率1 31 I-antiEGFR-BSA-PCL组均高于131I-BSA-PCL组(t-2.517、2.821,P<0.05),且均高于同组其他剂量(U251:t=2.148、2.693,P<0.05;U87:t=2.436、2.615,P<0.05).裸鼠体内实验发现两种纳米载体瘤体内注射后均经过肝脏代谢.131I-antiEGFR-BSA-PCL组荷瘤裸鼠的种植瘤体积较1 31 I-BSA-PCL组缩小更多(=4.115,P<0.05).结论 131I-antiEGFR-BSA-PCL在体内外实验中均能够抑制胶质瘤生长,为胶质瘤的治疗和预后评估提供了一种新方法.%Objective To explore the feasibility of treating glioma with 131 I-labeled antiEGFR nanoparticales in vitro and in vivo.Methods Radioiodine-labeled anti-EGFR binding nanoparticles were constructed and its in vitro cell-binding ability was confirmed by confocal microscopy and flow cytometry.Cell cytotoxicity of the drug was evaluated by MTT assay.Radioiodine-imaging studies were conducted by using a xenograft nude mouse model in vivo by detecting the change of the volume of the xenograft.Results In vitro studies revealed that the anti-EGFR nanoparticles binding with bovine serum

  2. 3-Bromopyruvate treatment induces alterations of metabolic and stress-related pathways in glioblastoma cells.

    Science.gov (United States)

    Chiasserini, Davide; Davidescu, Magdalena; Orvietani, Pier Luigi; Susta, Federica; Macchioni, Lara; Petricciuolo, Maya; Castigli, Emilia; Roberti, Rita; Binaglia, Luciano; Corazzi, Lanfranco

    2017-01-30

    Glioblastoma (GBM) is the most common and aggressive brain tumour of adults. The metabolic phenotype of GBM cells is highly dependent on glycolysis; therefore, therapeutic strategies aimed at interfering with glycolytic pathways are under consideration. 3-Bromopyruvate (3BP) is a potent antiglycolytic agent, with a variety of targets and possible effects on global cell metabolism. Here we analyzed the changes in protein expression on a GBM cell line (GL15 cells) caused by 3BP treatment using a global proteomic approach. Validation of differential protein expression was performed with immunoblotting and enzyme activity assays in GL15 and U251 cell lines. The results show that treatment of GL15 cells with 3BP leads to extensive changes in the expression of glycolytic enzymes and stress related proteins. Importantly, other metabolisms were also affected, including pentose phosphate pathway, aminoacid synthesis, and glucose derivatives production. 3BP elicited the activation of stress response proteins, as shown by the phosphorylation of HSPB1 at serine 82, caused by the concomitant activation of the p38 pathway. Our results show that inhibition of glycolysis in GL15 cells by 3BP influences different but interconnected pathways. Proteome analysis may help in the molecular characterization of the glioblastoma response induced by pharmacological treatment with antiglycolytic agents.

  3. Manool, a Salvia officinalis diterpene, induces selective cytotoxicity in cancer cells.

    Science.gov (United States)

    de Oliveira, Pollyanna Francielli; Munari, Carla Carolina; Nicolella, Heloiza Diniz; Veneziani, Rodrigo Cassio Sola; Tavares, Denise Crispim

    2016-10-01

    Manool, a diterpene isolated from Salvia officinalis, was evaluated by the XTT colorimetric assay for cytotoxicity and selectivity against different cancer cell lines: B16F10 (murine melanoma), MCF-7 (human breast adenocarcinoma), HeLa (human cervical adenocarcinoma), HepG2 (human hepatocellular carcinoma), and MO59J, U343 and U251 (human glioblastoma). A normal cell line (V79, Chinese hamster lung fibroblasts) was used to compare the selectivity of the test substance. Manool exhibited higher cytotoxic activity against HeLa (IC50 = 6.7 ± 1.1 µg/mL) and U343 (IC50 = 6.7 ± 1.2 µg/mL) cells. In addition, in the used experimental protocols, the treatment with manool was significantly more cytotoxic for different tumor cell lines than for the normal cell line V79 (IC50 = 49.3 ± 3.3 µg/mL), and showed high selectivity. These results suggest that manool may be used to treat cancer without affecting normal cells.

  4. TAZ promotes temozolomide resistance by upregulating MCL-1 in human glioma cells.

    Science.gov (United States)

    Tian, Tian; Li, Aimin; Lu, Hong; Luo, Ran; Zhang, Mingzhi; Li, Zhaoming

    2015-08-07

    Temozolomide is a novel cytotoxic agent currently used as first-line chemotherapy for glioblastoma multiforme (GBM). However, intrinsic or acquired chemoresistance to temozolomide remains the greatest obstacle to the successful treatment of human GBM. The principal mechanism responsible for this resistance is largely unknown. In the present study, we showed that expression of transcriptional co-activator with PDZ-binding motif (TAZ) in glioma cells correlated with temozolomide chemoresistance in human glioma cells. Overexpression of TAZ promoted temozolomide resistance in U-87MG cells, whereas knockdown of TAZ expression sensitized temozolomide-resistant U-251MG cells to temozolomide. Further, TAZ inhibits temozolomide induced apoptosis via upregulation of MCL-1 (myeloid cell leukemia 1) and high expression of TAZ predicts a poor prognosis for GBM patients. In conclusion, our results suggest that TAZ had a critical role in the resistance to temozolomide in glioma cells, and it may provide a promising target for improving the therapeutic outcome of temozolomide-resistant gliomas.

  5. Laminin isoforms and their integrin receptors in glioma cell migration and invasiveness: Evidence for a role of alpha5-laminin(s) and alpha3beta1 integrin.

    Science.gov (United States)

    Kawataki, Tomoyuki; Yamane, Tetsu; Naganuma, Hirofumi; Rousselle, Patricia; Andurén, Ingegerd; Tryggvason, Karl; Patarroyo, Manuel

    2007-11-01

    Glioma cell infiltration of brain tissue often occurs along the basement membrane (BM) of blood vessels. In the present study we have investigated the role of laminins, major structural components of BMs and strong promoters of cell migration. Immunohistochemical studies of glioma tumor tissue demonstrated expression of alpha2-, alpha3-, alpha4- and alpha5-, but not alpha1-, laminins by the tumor vasculature. In functional assays, alpha3 (Lm-332/laminin-5)- and alpha5 (Lm-511/laminin-10)-laminins strongly promoted migration of all glioma cell lines tested. alpha1-Laminin (Lm-111/laminin-1) displayed lower activity, whereas alpha2 (Lm-211/laminin-2)- and alpha4 (Lm-411/laminin-8)-laminins were practically inactive. Global integrin phenotyping identified alpha3beta1 as the most abundant integrin in all the glioma cell lines, and this laminin-binding integrin exclusively or largely mediate the cell migration. Moreover, pretreatment of U251 glioma cells with blocking antibodies to alpha3beta1 integrin followed by intracerebral injection into nude mice inhibited invasion of the tumor cells into the brain tissue. The cell lines secreted Lm-211, Lm-411 and Lm-511, at different ratios. The results indicate that glioma cells secrete alpha2-, alpha4- and alpha5-laminins and that alpha3- and alpha5-laminins, found in brain vasculature, selectively promote glioma cell migration. They identify alpha3beta1 as the predominant integrin and laminin receptor in glioma cells, and as a brain invasion-mediating integrin.

  6. NETRIN-4 protects glioblastoma cells FROM temozolomide induced senescence.

    Directory of Open Access Journals (Sweden)

    Li Li

    Full Text Available Glioblastoma multiforme is the most common primary tumor of the central nervous system. The drug temozolomide (TMZ prolongs lifespan in many glioblastoma patients. The sensitivity of glioblastoma cells to TMZ is interfered by many factors, such as the expression of O-6-methylguanine-DNA methyltransferase (MGMT and activation of AKT signaling. We have recently identified the interaction between netrin-4 (NTN4 and integrin beta-4 (ITGB4, which promotes glioblastoma cell proliferation via activating AKT-mTOR signaling pathway. In the current work we have explored the effect of NTN4/ITGB4 interaction on TMZ induced glioblastoma cell senescence. We report here that the suppression of either ITGB4 or NTN4 in glioblastoma cell lines significantly enhances cellular senescence. The sensitivity of GBM cells to TMZ was primarily determined by the expression of MGMT. To omit the effect of MGMT, we concentrated on the cell lines devoid of expression of MGMT. NTN4 partially inhibited TMZ induced cell senescence and rescued AKT from dephosphorylation in U251MG cells, a cell line bearing decent levels of ITGB4. However, addition of exogenous NTN4 displayed no significant effect on TMZ induced senescence rescue or AKT activation in U87MG cells, which expressed ITGB4 at low levels. Furthermore, overexpression of ITGB4 combined with exogenous NTN4 significantly attenuated U87MG cell senescence induced by TMZ. These data suggest that NTN4 protects glioblastoma cells from TMZ induced senescence, probably via rescuing TMZ triggered ITGB4 dependent AKT dephosphorylation. This suggests that interfering the interaction between NTN4 and ITGB4 or concomitant use of the inhibitors of the AKT pathway may improve the therapeutic efficiency of TMZ.

  7. NETRIN-4 protects glioblastoma cells FROM temozolomide induced senescence.

    Science.gov (United States)

    Li, Li; Hu, Yizhou; Ylivinkka, Irene; Li, Huini; Chen, Ping; Keski-Oja, Jorma; Hyytiäinen, Marko

    2013-01-01

    Glioblastoma multiforme is the most common primary tumor of the central nervous system. The drug temozolomide (TMZ) prolongs lifespan in many glioblastoma patients. The sensitivity of glioblastoma cells to TMZ is interfered by many factors, such as the expression of O-6-methylguanine-DNA methyltransferase (MGMT) and activation of AKT signaling. We have recently identified the interaction between netrin-4 (NTN4) and integrin beta-4 (ITGB4), which promotes glioblastoma cell proliferation via activating AKT-mTOR signaling pathway. In the current work we have explored the effect of NTN4/ITGB4 interaction on TMZ induced glioblastoma cell senescence. We report here that the suppression of either ITGB4 or NTN4 in glioblastoma cell lines significantly enhances cellular senescence. The sensitivity of GBM cells to TMZ was primarily determined by the expression of MGMT. To omit the effect of MGMT, we concentrated on the cell lines devoid of expression of MGMT. NTN4 partially inhibited TMZ induced cell senescence and rescued AKT from dephosphorylation in U251MG cells, a cell line bearing decent levels of ITGB4. However, addition of exogenous NTN4 displayed no significant effect on TMZ induced senescence rescue or AKT activation in U87MG cells, which expressed ITGB4 at low levels. Furthermore, overexpression of ITGB4 combined with exogenous NTN4 significantly attenuated U87MG cell senescence induced by TMZ. These data suggest that NTN4 protects glioblastoma cells from TMZ induced senescence, probably via rescuing TMZ triggered ITGB4 dependent AKT dephosphorylation. This suggests that interfering the interaction between NTN4 and ITGB4 or concomitant use of the inhibitors of the AKT pathway may improve the therapeutic efficiency of TMZ.

  8. AS1411-Induced Growth Inhibition of Glioma Cells by Up-Regulation of p53 and Down-Regulation of Bcl-2 and Akt1 via Nucleolin.

    Science.gov (United States)

    Cheng, Ye; Zhao, Gang; Zhang, Siwen; Nigim, Fares; Zhou, Guangtong; Yu, Zhiyun; Song, Yang; Chen, Yong; Li, Yunqian

    2016-01-01

    AS1411 binds nucleolin (NCL) and is the first oligodeoxynucleotide aptamer to reach phase I and II clinical trials for the treatment of several cancers. However, the mechanisms by which AS1411 targets and kills glioma cells and tissues remain unclear. Here we report that AS1411 induces cell apoptosis and cycle arrest, and inhibits cell viability by up-regulation of p53 and down-regulation of Bcl-2 and Akt1 in human glioma cells. NCL was overexpressed in both nucleus and cytoplasm in human glioma U87, U251 and SHG44 cells compared to normal human astrocytes (NHA). AS1411 bound NCL and inhibited the proliferation of glioma cells but not NHA, which was accompanied with up-regulation of p53 and down-regulation of Bcl-2 and Akt1. Moreover, AS1411 treatment resulted in the G2/M cell cycle arrest in glioma cells, which was however abolished by overexpression of NCL. Further, AS1411 induced cell apoptosis, which was prevented by silencing of p53 and overexpression of Bcl-2. In addition, AS1411 inhibited the migration and invasion of glioma cells in an Akt1-dependent manner. Importantly, AS1411 inhibited the growth of glioma xenograft and prolonged the survival time of glioma tumor-bearing mice. These results revealed a promising treatment of glioma by oligodeoxynucleotide aptamer.

  9. A complex mechanism for HDGF-mediated cell growth, migration, invasion, and TMZ chemosensitivity in glioma.

    Science.gov (United States)

    Song, Ye; Hu, Zheng; Long, Hao; Peng, Yuping; Zhang, Xi'an; Que, Tianshi; Zheng, Shihao; Li, Zhiyong; Wang, Gang; Yi, Liu; Liu, Zhen; Fang, Weiyi; Qi, Songtao

    2014-09-01

    HDGF is overexpressed in gliomas as compared to normal brain. We therefore analyzed the molecular mechanisms of HDGF action in gliomas. HDGF was downregulated in normal brain tissue as compared to glioma specimens at both the mRNA and the protein levels. In glioma samples, increased HDGF expression was associated with disease progression. Knocking down HDGF expression not only significantly decreased cellular proliferation, migration, invasion, and tumorigenesis, but also markedly enhanced TMZ-induced cytotoxicity and apoptosis in glioma cells. Mechanistic analyses revealed that CCND1, c-myc, and TGF-β were downregulated after stable HDGF knockdown in the U251 and U87 glioma cells. HDGF knockdown restored E-cadherin expression and suppressed mesenchymal cell markers such as vimentin, β-catenin, and N-cadherin. The expression of cleaved caspase-3 increased, while Bcl-2 decreased in each cell line following treatment with shHDGF and TMZ, as compared to TMZ alone. Furthermore, RNAi-based knockdown study revealed that HDGF is probably involved in the activation of both the PI3K/Akt and the TGF-β signaling pathways. Together, our data suggested that HDGF regulates glioma cell growth, apoptosis and epithelial-mesenchymal transition (EMT) probably through the Akt and the TGF-β signaling pathways. These results provide evidence that targeting HDGF or its downstream targets may lead to novel therapies for gliomas.

  10. Interferon-α/β Enhance Temozolomide Activity against MGMT-positive Glioma Stem Cells in Vitro%干扰素-α/β体外增敏替莫唑胺对MGMT阳性胶质瘤干细胞作用

    Institute of Scientific and Technical Information of China (English)

    沈冬; 仇志坤; 陈银生; 陈芙蓉; 陈忠平

    2012-01-01

    [Objective] O6 methylguanine DNA methylbanferase (MGMT) is one of the main mechanisms of chemoresistance for alkylaling agents in malignant glioma. Recent studies showed that glioma stem cells (GSC) was the main cause for tumor recurrence and chemoresistance. This study aimed to explore the effects of interferon-a/β against MGMT-positive glioma stem cells, and to investigate whether Interferon-a/β can enhance the efficiency of temozolomide and the possible mechanism. [Methods] Glioma cell line U251 and SKMG-4, MCMT-negative in conventional culture, were induced through serum-free clone culture to get MGMT-positive GSC U2S1G and SKMG-4G. CCK-8 assay was used to test the growth inhibition effect of temozolomide with interferon-a/p against the MGMT-positive GSC. RT-PCR and Western blot analysis were applied to detect the MGMT and NF-KB expression in MGMT-positive GSC administered by interfenm-a/β. [Results] GSC were successfully obtained from two parental glioma cell lines U251 and SKMG-4, and MGMT expression in GSC was significantly increased determined by Western blot analysis. The chemotherapy sensitivity of temozolomide was significantly enhanced by using intederon-a/β in vitro. The expression of NF-KB and MCMT in MGMT-positive GSC decreased significantly in both mRNA and protein levels after using interferon-a/p through RT-PCR and Western-blot tests. [Conclusion] As to MGMT-positive GSC, interferoo-a/β can enhance the sensitivity of temozolomide, and down-regulate NF-KB expression, lower MGMT transcription expression and reverse the chemoresistance of temozolomide.%[目的]探讨干扰素是否能增加替莫唑胺(TMZ)对O6甲基鸟嘌呤DNA甲基转移酶(MGMT)阳性胶质瘤干细胞的抗肿瘤作用及其可能机制.[方法]采用“悬浮克隆球形成法”对常规培养条件下MGMT阴性表达的胶质瘤细胞株U251、SKMG-4进行诱导,获得MGMT阳性的胶质瘤干细胞U251G、SKMC-4G;应用CCK-8法检测干扰素-α和干扰素-β联合

  11. Cannabinoid receptor CB1 regulates STAT3 activity and its expression dictates the responsiveness to SR141716 treatment in human glioma patients' cells.

    Science.gov (United States)

    Ciaglia, Elena; Torelli, Giovanni; Pisanti, Simona; Picardi, Paola; D'Alessandro, Alba; Laezza, Chiara; Malfitano, Anna Maria; Fiore, Donatella; Pagano Zottola, Antonio Christian; Proto, Maria Chiara; Catapano, Giuseppe; Gazzerro, Patrizia; Bifulco, Maurizio

    2015-06-20

    Herein we show that a majority of human brain tumor samples and cell lines over-expressed cannabinoid receptor CB1 as compared to normal human astrocytes (NHA), while uniformly expressed low levels of CB2. This finding prompted us to investigate the therapeutic exploitation of CB1 inactivation by SR141716 treatment, with regard to its direct and indirect cell-mediated effects against gliomas. Functional studies, using U251MG glioma cells and primary tumor cell lines derived from glioma patients expressing different levels of CB1, highlighted SR141716 efficacy in inducing apoptosis via G1 phase stasis and block of TGF-β1 secretion through a mechanism that involves STAT3 inhibition. According to the multivariate role of STAT3 in the immune escape too, interestingly SR141716 lead also to the functional and selective expression of MICA/B on the surface of responsive malignant glioma cells, but not on NHA. This makes SR141716 treated-glioma cells potent targets for allogeneic NK cell-mediated recognition through a NKG2D restricted mechanism, thus priming them for NK cell antitumor reactivity. These results indicate that CB1 and STAT3 participate in a new oncogenic network in the complex biology of glioma and their expression levels in patients dictate the efficacy of the CB1 antagonist SR141716 in multimodal glioma destruction.

  12. Inhibition of STAT3 reduces astrocytoma cell invasion and constitutive activation of STAT3 predicts poor prognosis in human astrocytoma.

    Directory of Open Access Journals (Sweden)

    Qinchuan Liang

    Full Text Available Astrocytoma cells characteristically possess high invasion potentials. Recent studies have revealed that knockdown of signal transducers and activators of transcription 3 (STAT3 expression by RNAi induces apoptosis in astrocytoma cell. Nevertheless, the distinct roles of STAT3 in astrocytoma's invasion and recurrence have not been elucidated. In this study, we silenced STAT3 using Small interfering RNAs in two human glioblastoma multiforme (GBM cell lines (U251 and U87, and investigated the effect on GBM cell adhesion and invasion. Our results demonstrate that disruption of STAT3 inhibits GBM cell's adhesion and invasion. Knockdown of STAT3 significantly increased E-cadherin but decreased N-cadherin, vascular endothelial growth factor, matrix metalloproteinase 2 and matrix metalloproteinase 9. Additionally, expression of pSTAT3(Tyr705 correlates with astrocytoma WHO classification, Karnofsky performance status scale score, tumor recurrence and survival. Furthermore, pSTAT3(Tyr705 is a significant prognostic factor in astrocytoma. In conclusion, STAT3 may affect astrocytoma invasion, expression of pSTAT3(Tyr705 is a significant prognostic factor in tumor recurrence and overall survival in astrocytoma patients. Therefore, STAT3 may provide a potential target for molecular therapy in human astrocytoma, and pSTAT3(Tyr705could be an important biomarker for astrocytoma prognosis.

  13. Silencing erythropoietin receptor on glioma cells reinforces efficacy of temozolomide and X-rays through senescence and mitotic catastrophe.

    Science.gov (United States)

    Pérès, Elodie A; Gérault, Aurélie N; Valable, Samuel; Roussel, Simon; Toutain, Jérôme; Divoux, Didier; Guillamo, Jean-Sébastien; Sanson, Marc; Bernaudin, Myriam; Petit, Edwige

    2015-02-10

    Hypoxia-inducible genes may contribute to therapy resistance in glioblastoma (GBM), the most aggressive and hypoxic brain tumours. It has been recently reported that erythropoietin (EPO) and its receptor (EPOR) are involved in glioma growth. We now investigated whether EPOR signalling may modulate the efficacy of the GBM current treatment based on chemotherapy (temozolomide, TMZ) and radiotherapy (X-rays). Using RNA interference, we showed on glioma cell lines (U87 and U251) that EPOR silencing induces a G2/M cell cycle arrest, consistent with the slowdown of glioma growth induced by EPOR knock-down. In vivo, we also reported that EPOR silencing combined with TMZ treatment is more efficient to delay tumour recurrence and to prolong animal survival compared to TMZ alone. In vitro, we showed that EPOR silencing not only increases the sensitivity of glioma cells to TMZ as well as X-rays but also counteracts the hypoxia-induced chemo- and radioresistance. Silencing EPOR on glioma cells exposed to conventional treatments enhances senescence and induces a robust genomic instability that leads to caspase-dependent mitotic death by increasing the number of polyploid cells and cyclin B1 expression. Overall these data suggest that EPOR could be an attractive target to overcome therapeutic resistance toward ionising radiation or temozolomide.

  14. Silencing erythropoietin receptor on glioma cells reinforces efficacy of temozolomide and X-rays through senescence and mitotic catastrophe

    Science.gov (United States)

    Pérès, Elodie A.; Gérault, Aurélie N.; Valable, Samuel; Roussel, Simon; Toutain, Jérôme; Divoux, Didier; Guillamo, Jean-Sébastien; Sanson, Marc; Bernaudin, Myriam; Petit, Edwige

    2015-01-01

    Hypoxia-inducible genes may contribute to therapy resistance in glioblastoma (GBM), the most aggressive and hypoxic brain tumours. It has been recently reported that erythropoietin (EPO) and its receptor (EPOR) are involved in glioma growth. We now investigated whether EPOR signalling may modulate the efficacy of the GBM current treatment based on chemotherapy (temozolomide, TMZ) and radiotherapy (X-rays). Using RNA interference, we showed on glioma cell lines (U87 and U251) that EPOR silencing induces a G2/M cell cycle arrest, consistent with the slowdown of glioma growth induced by EPOR knock-down. In vivo, we also reported that EPOR silencing combined with TMZ treatment is more efficient to delay tumour recurrence and to prolong animal survival compared to TMZ alone. In vitro, we showed that EPOR silencing not only increases the sensitivity of glioma cells to TMZ as well as X-rays but also counteracts the hypoxia-induced chemo- and radioresistance. Silencing EPOR on glioma cells exposed to conventional treatments enhances senescence and induces a robust genomic instability that leads to caspase-dependent mitotic death by increasing the number of polyploid cells and cyclin B1 expression. Overall these data suggest that EPOR could be an attractive target to overcome therapeutic resistance toward ionising radiation or temozolomide. PMID:25544764

  15. The Cytotoxic Effect of Small and Large Molecules of PMF Fraction Extracted from Camel Urine on Cancer Cells

    KAUST Repository

    Khorshid, Faten

    2015-01-10

    Aim of the work: Animal urine, including that of camels, has long been used for the therapeutic management of human ailments. In this study, we sought to characterize the cytotoxic properties of newly derived purified fractions from previously described camel urine extract (PMF) on various cancer cell lines. Methodology: Two new size dissimilar fractions of PMF (large and small) were obtained by fractionalizing PMF using 3kD and 50kD membrane filters. A SRB cytotoxicity assay of the PMF fractions was performed on cancer cell lines (A549, HCT116, HepG2, MCF-7, U251 and Hela) as well as normal cell lines (human fibroblast cell line and Vero). Results: This study showed that the newly derived and more purified fraction of PMF (new PMF) possesses effective and selective anti-cancer properties against several types of cancer cell lines. Conclusion: This study, as well as previous ones, suggests that camel urine extracts (old and new PMF) may provide newer therapeutic alternatives to clinically manage cancer patients. However, further studies are needed to verify these positive preliminary results.

  16. FRK inhibits migration and invasion of human glioma cells by promoting N-cadherin/β-catenin complex formation.

    Science.gov (United States)

    Shi, Qiong; Song, Xu; Wang, Jun; Gu, Jia; Zhang, Weijian; Hu, Jinxia; Zhou, Xiuping; Yu, Rutong

    2015-01-01

    Fyn-related kinase (FRK), a member of Src-related tyrosine kinases, is recently reported to function as a potent tumor suppressor in several cancer types. Our previous study has also shown that FRK over-expression inhibited the migration and invasion of glioma cells. However, the mechanism of FRK effect on glioma cell migration and invasion, a feature of human malignant gliomas, is still not clear. In this study, we found that FRK over-expression increased the protein level of N-cadherin, but not E-cadherin. Meanwhile, FRK over-expression promoted β-catenin translocation to the plasma membrane, where it formed complex with N-cadherin, while decreased β-catenin level in the nuclear fraction. In addition, down-regulation of N-cadherin by siRNA promoted the migration and invasion of glioma U251 and U87 cells and abolished the inhibitory effect of FRK on glioma cell migration and invasion. In summary, these results indicate that FRK inhibits migration and invasion of human glioma cells by promoting N-cadherin/β-catenin complex formation.

  17. 锯叶棕提取物对人脑胶质瘤细胞凋亡和PI3K蛋白表达影响的研究%The Study of Saw Palmetto Extract on the Effect of Glioma Cell Apoptosis and Expression of PI3K Protein

    Institute of Scientific and Technical Information of China (English)

    侯率; 杨姝; 王元元; 吕回; 车玉琴

    2014-01-01

    目的:通过锯叶棕提取物对人脑胶质瘤细胞的干预,观察人脑胶质瘤细胞中细胞凋亡和PI3K蛋白表达的变化。方法体外培养U251细胞,应用锯叶棕提取物进行预处理,应用TUNEL法检测细胞凋亡,应用Western Blot法检测PI3K蛋白表达水平的变化。结果TUNEL法染色检测锯叶棕提取物对人脑胶质瘤细胞凋亡的影响,24 h与48 h均可见TUNEL阳性反应细胞即凋亡细胞,胞体缩小,形态不规则,胞核固缩浓染,呈棕黄色或棕褐色;1.5μL/mL组48 h与24 h比较,凋亡数量显著增多(P<0.01);对照组24 h与48 h偶见凋亡细胞,2.0μL/mL组与1.5μL/mL组比较,凋亡率增大(P<0.01)。用Western blot法检测锯叶棕提取物对人脑胶质瘤细胞PI3K蛋白表达的影响,锯叶棕提取物预处理U251细胞与对照组比较, PI3K蛋白表达水平显著降低(P<0.01)。结论锯叶棕提取物能诱导人脑胶质瘤细胞凋亡;锯叶棕提取物诱导人脑胶质瘤细胞凋亡的机制可能是通过阻断PI3K/Akt信号转导通路。%Objective To observe the effect of saw palmetto extract on glioma cell apoptosis and the influence of PI3K in glioma cells through the intervention of saw palmetto on glioma cell. Methods U251 cells are cultured in vitro, pre-treatment with saw palmetto extract, to detect the cell apoptosis by TUNEL method, to detect the changes of the expression of PI3K by Western blot. Results 1.TUNEL method staining to detect the effect of saw palmetto extract on glioma cell apoptosis. (1)Both 24 h and 48 h time point see TUNEL positive cells (apoptotic cells), cell body narrow, irregular, nucleus condensation stain, showed brown yellow or brown, 48 h and 24 h compare, the number of apoptotic cells significantly increased in 1.5μL/mL group (P<0.01);(2)24 h and 48 h time point occasionally see apoptotic cells in the control group, the same time 1.5μL/mL and 2.0μL/mL group, number of apoptotic cells

  18. Understanding dynamic changes in live cell adhesion with neutron reflectometry

    Science.gov (United States)

    Junghans, Ann

    Understanding the structure and functionality of biological systems on a nanometer-resolution and short temporal scales is important for solving complex biological problems, developing innovative treatment, and advancing the design of highly functionalized biomimetic materials. For example, adhesion of cells to an underlying substrate plays a crucial role in physiology and disease development, and has been investigated with great interest for several decades. In the talk, we would like to highlight recent advances in utilizing neutron scattering to study bio-related structures in dynamic conditions (e . g . under the shear flow) including in-situ investigations of the interfacial properties of living cells. The strength of neutron reflectometry is its non-pertubative nature, the ability to probe buried interfaces with nanometer resolution and its sensitivity to light elements like hydrogen and carbon. That allows us to study details of cell - substrate interfaces that are not accessible with any other standard techniques. We studied the adhesion of human brain tumor cells (U251) to quartz substrates and their responses to the external mechanical forces. Such cells are isolated within the central nervous system which makes them difficult to reach with conventional therapies and therefore making them highly invasive. Our results reveal changes in the thickness and composition of the adhesion layer (a layer between the cell lipid membrane and the quartz substrate), largely composed of hyaluronic acid and associated proteoglycans, when the cells were subjected to shear stress. Further studies will allow us to determine more conditions triggering changes in the composition of the bio-material in the adhesion layer. This, in turn, can help to identify changes that correlate with tumor invasiveness, which can have significant medical impact for the development of targeted anti-invasive therapies.

  19. Leucine-rich repeat C4 protein is Involved in Nervous Tissue Development and Neurite Outgrowth, and Induction of Glioma Cell Differentiation

    Institute of Scientific and Technical Information of China (English)

    Minghua WU; Jianhong LU; Shourong SHEN; Guiyuan LI; He HUANG; Qiong CHEN; Dan LI; Zhaoyang ZENG; Wei XIONG; Yanhong ZHOU; Xiaoling LI; Ming ZHOU

    2007-01-01

    LRRC4, leucine-rich repeat C4 protein, has been identified in human (GenBank accession No.AF196976), mouse (GenBank accession No. DQ177325), rat (GenBank accession No. DQ119102) and bovine (GenBank accession No. DQ164537) with identical domains. In terms of their similarity, the genes encoding LRRC4 in these four mammalian species are orthogs and therefore correspond to the same gene entity. Based on previous research, and using in situ hybridization, we found that LRRC4 had the strongest expression in hippocampal CA1 and CA2, the granule cells of the dentate gyrus region, the mediodoral thalamic nucleus, and cerebella Purkinje cell layers. Using a P19 cell model, we also found that LRRC4 participates in the differentiation of neuron and glia cells. In addition, extracellular proteins containing both an LRR cassette and immunoglobulin domains have been shown to participate in axon guidance. Our data from neurite outgrowth assays indicated that LRRC4 promoted neurite extension of hippocampal neurons, and induced differentiation of glioblastoma U251 cells into astrocyte-like cells, confirmed by morphology observation and glial fibrillary acidic protein expression.

  20. Aptamer modification improves the adenoviral transduction of malignant glioma cells.

    Science.gov (United States)

    Chen, Hao; Zheng, Xiaojing; Di, BingYan; Wang, Dongyang; Zhang, Yaling; Xia, Haibin; Mao, Qinwen

    2013-12-01

    Adenovirus has shown increasing promise in the gene-viral therapy for glioblastoma, a treatment strategy that relies on the delivery of viruses or transgenes into tumor cells. However, targeting of adenovirus to human glioblastoma remains a challenge due to the low expression level of coxsackie and adenovirus receptor (CAR) in glioma cells. Aptamers are small and highly structured single-stranded oligonucleotides that bind at high affinity to a target molecule, and are good candidates for targeted imaging and therapy. In this study, to construct an aptamer-modified Ad5, we first genetically modified the HVR5 of Ad hexon by biotin acceptor peptide (BAP), which would be metabolically biotinylated during production in HEK293 cells, and then attached the biotin labeled aptamer to the modified Ad through avidin–biotin binding. The aptamers used in this study includes AS1411 and GBI-10. The former is a DNA aptamer that can bind to nucleolin, a nuclear matrix protein found on the surface of cancer cells. The latter is a DNA aptamer that can recognize the extracellular matrix protein tenascin-C on the surface of human glioblastoma cells. To examine if aptamer-modification of the hexon protein could improve the adenoviral transduction efficiency, a glioblastoma cell line, U251, was transduced with aptamer-modified Ads. The transduction efficiency of AS1411- or GBI-10-modified Ad was approximately 4.1-fold or 5.2-fold higher than that of the control. The data indicated that aptamer modified adenovirus would be a useful tool for cancer gene therapy.

  1. 缺氧诱导因子-1抑制剂细胞筛选模型的建立及抑制剂研究%Identification of two small molecule inhibitors of hypoxia-inducible factor 1 with different cell-based screening model

    Institute of Scientific and Technical Information of China (English)

    郎立伟; 唐克; 李燕; 刘晓宇; 王超; 陈晓光

    2012-01-01

    目的:建立并应用2种缺氧诱导因子-1( HIF-1)抑制剂细胞筛选模型对雷公藤甲素和三白脂素-8活性进行评价,为HIF-1靶点抑制剂的研发提供基础.方法:建立基于报告基因的HIF-1抑制剂细胞筛选模型,U251 -HRE和T47D-HRE细胞模型,分别对雷公藤甲素与三白脂素-8活性进行检测,观察其对下游关键调控基因VEGF表达的影响,并用MTT法比较2类抑制剂对多种实体瘤细胞的增殖抑制活性.结果:2种细胞模型在1% O2缺氧20 h,由HIF-1诱导的荧光素酶高表达,可用于抑制剂的活性评价.雷公藤甲素对U251 -HRE细胞模型敏感,其HIF-1抑制活性IC50(3.4±0.5)×10-8 mol· L-1,而三白脂素-8对T47D-HRE细胞模型敏感,其IC50 (2.4±0.6)×10-8 mol·L-1;雷公藤甲素和三白脂素-8在1×10-7mol·L-1都可对T47D细胞因缺氧所致的VEGF表达升高产生明显抑制作用,其抑制率分别为85.2%,62.6%;雷公藤甲素对所测肿瘤细胞株都有明显的增殖抑制活性,而三白脂素-8对乳腺癌、胰腺癌细胞株较为敏感.结论:针对不同类别的HIF-1抑制剂建立相应敏感的特异性细胞筛选模型至关重要.%Objective: To investigate the inhibitory activity of HIF-1 by triptolide and manasaantin A, two cell-based models with luciferase report gene assay were established. Method: Two cell-based models of HIF-1 were used to evaluate HIF-1 inhibition activity of triptolide and manasaantin A. Secreted VEGF expression induced by hypoxia was detected by ELISA with two compounds. The growth inhibition of different solid tumor cell lines was measured by the MTT assay. Result: The expression of firefly luciferase was induced by hypoxia in U251-HRE and T47D-HRE cells. U251-HRE model was suitable for the detection of HIF-1 inhibition activity of triptolide. The IC50 of triptolide on HIF-1 activity was (3.4±0.5) × 10 mol · L-1 . The report gene assay using T47D cells co-trans-fected with pGL2-TK-HRE and pRL-CMV showed more

  2. High expression of adenylate cyclase-associated protein 1 accelerates the proliferation, migration and invasion of neural glioma cells.

    Science.gov (United States)

    Bao, Zhen; Qiu, Xiaojun; Wang, Donglin; Ban, Na; Fan, Shaochen; Chen, Wenjuan; Sun, Jie; Xing, Weikang; Wang, Yunfeng; Cui, Gang

    2016-04-01

    Adenylate cyclase-associated protein 1 (CAP1), a conserved member of cyclase-associated proteins was reported to be associated with the proliferation, migration or invasion of the tumors of pancreas, breast and liver, and was involved in astrocyte proliferation after acute Traumatic Brain Injury (TBI). In this study, we sought to investigate the character of CAP1 in the pathological process of human glioma by detecting human glioma specimens and cell lines. 43 of 100 specimens showed high expression of CAP1 via immunohistochemistry. With statistics analysis, we found out the expression level of CAP1 was correlated with the WHO grades of human glioma and was great positively related to Ki-67 (p<0.01). In vitro, silencing CAP1 in U251 and U87MG, the glioma cell lines with the relatively higher expression of CAP1, induced the proliferation of the cells significantly retarded, migration and invasion as well. Obviously, our results indicated that CAP1 participated in the molecular pathological process of glioma indeed, and in a certain sense, CAP1 might be a potential and promising molecular target for glioma diagnosis and therapies in the future.

  3. A preliminary investigation into the impact of a pesticide combination on human neuronal and glial cell lines in vitro.

    Directory of Open Access Journals (Sweden)

    Michael D Coleman

    Full Text Available Many pesticides are used increasingly in combinations during crop protection and their stability ensures the presence of such combinations in foodstuffs. The effects of three fungicides, pyrimethanil, cyprodinil and fludioxonil, were investigated together and separately on U251 and SH-SY5Y cells, which can be representative of human CNS glial and neuronal cells respectively. Over 48h, all three agents showed significant reductions in cellular ATP, at concentrations that were more than tenfold lower than those which significantly impaired cellular viability. The effects on energy metabolism were reflected in their marked toxic effects on mitochondrial membrane potential. In addition, evidence of oxidative stress was seen in terms of a fall in cellular thiols coupled with increases in the expression of enzymes associated with reactive species formation, such as GSH peroxidase and superoxide dismutase. The glial cell line showed significant responsiveness to the toxin challenge in terms of changes in antioxidant gene expression, although the neuronal SH-SY5Y line exhibited greater vulnerability to toxicity, which was reflected in significant increases in caspase-3 expression, which is indicative of the initiation of apoptosis. Cyprodinil was the most toxic agent individually, although oxidative stress-related enzyme gene expression increases appeared to demonstrate some degree of synergy in the presence of the combination of agents. This report suggests that the impact of some pesticides, both individually and in combinations, merits further study in terms of their impact on human cellular health.

  4. Suppression of autophagy augments the radiosensitizing effects of STAT3 inhibition on human glioma cells

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, Xiaopeng; Du, Jie; Hua, Song; Zhang, Haowen; Gu, Cheng; Wang, Jie; Yang, Lei; Huang, Jianfeng; Yu, Jiahua, E-mail: yujiahua@suda.edu.cn; Liu, Fenju, E-mail: fangsh@suda.edu.cn

    2015-01-15

    Radiotherapy is an essential component of the standard therapy for newly diagnosed glioblastoma. To increase the radiosensitivity of glioma cells is a feasible solution to improve the therapeutic effects. It has been suggested that inhibition of signal transducer and activator of transcription 3 (STAT3) can radiosensitize glioma cells, probably via the activation of mitochondrial apoptotic pathway. In this study, human malignant glioma cells, U251 and A172, were treated with an STAT3 inhibitor, WP1066, or a short hairpin RNA plasmid targeting STAT3 to suppress the activation of STAT3 signaling. The radiosensitizing effects of STAT3 inhibition were confirmed in glioma cells. Intriguingly, combination of ionizing radiation exposure and STAT3 inhibition triggered a pronounced increase of autophagy flux. To explore the role of autophagy, glioma cells were treated with 3-methyladenine or siRNA for autophagy-related gene 5, and it was demonstrated that inhibition of autophagy further strengthened the radiosensitizing effects of STAT3 inhibition. Accordingly, more apoptotic cells were induced by the dual inhibition of autophagy and STAT3 signaling. In conclusion, our data revealed a protective role of autophagy in the radiosensitizing effects of STAT3 inhibition, and inhibition of both autophagy and STAT3 might be a potential therapeutic strategy to increase the radiosensitivity of glioma cells. - Highlights: • Inactivation of STAT3 signaling radiosensitizes malignant glioma cells. • STAT3 inhibition triggers a significant increase of autophagy flux induced by ionizing radiation in glioma cells. • Suppression of autophagy further strengthens the radiosensitizing effects of STAT3 inhibition in glioma cells. • Dual inhibition of autophagy and STAT3 induce massive apoptotic cells upon exposure to ionizing radiation.

  5. A chalcone-related small molecule that induces methuosis, a novel form of non-apoptotic cell death, in glioblastoma cells

    Directory of Open Access Journals (Sweden)

    Bhanot Haymanti

    2011-06-01

    Full Text Available Abstract Background Methuosis is a unique form of non-apoptotic cell death triggered by alterations in the trafficking of clathrin-independent endosomes, ultimately leading to extreme vacuolization and rupture of the cell. Results Here we describe a novel chalcone-like molecule, 3-(2-methyl-1H- indol-3-yl-1-(4-pyridinyl-2-propen-1-one (MIPP that induces cell death with the hallmarks of methuosis. MIPP causes rapid accumulation of vacuoles derived from macropinosomes, based on time-lapse microscopy and labeling with extracellular fluid phase tracers. Vacuolization can be blocked by the cholesterol-interacting compound, filipin, consistent with the origin of the vacuoles from non-clathrin endocytic compartments. Although the vacuoles rapidly acquire some characteristics of late endosomes (Rab7, LAMP1, they remain distinct from lysosomal and autophagosomal compartments, suggestive of a block at the late endosome/lysosome boundary. MIPP appears to target steps in the endosomal trafficking pathway involving Rab5 and Rab7, as evidenced by changes in the activation states of these GTPases. These effects are specific, as other GTPases (Rac1, Arf6 are unaffected by the compound. Cells treated with MIPP lose viability within 2-3 days, but their nuclei show no evidence of apoptotic changes. Inhibition of caspase activity does not protect the cells, consistent with a non-apoptotic death mechanism. U251 glioblastoma cells selected for temozolomide resistance showed sensitivity to MIPP-induced methuosis that was comparable to the parental cell line. Conclusions MIPP might serve as a prototype for new drugs that could be used to induce non-apoptotic death in cancers that have become refractory to agents that work through DNA damage and apoptotic mechanisms.

  6. Impact of flattening-filter-free radiation on the clonogenic survival of astrocytic cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Steenken, Caroline; Fleckenstein, Jens; Kegel, Stefan; Jahnke, Lennart; Simeonova, Anna; Hartmann, Linda; Kuebler, Jens; Veldwijk, Marlon R.; Wenz, Frederik; Herskind, Carsten; Giordano, Frank Anton [Universitaetsmedizin Mannheim (UMM), Medical Faculty Mannheim, Heidelberg University, Department of Radiation Oncology, Mannheim (Germany)

    2015-07-15

    Flattening-filter-free (FFF) beams are increasingly used in radiotherapy as delivery times can be substantially reduced. However, the relative biologic effectiveness (RBE) of FFF may be increased relative to conventional flattened (FLAT) beams due to differences in energy spectra. Therefore, we investigated the effects of FFF and FLAT beams on the clonogenic survival of astrocytoma cells. Three cell lines (U251, U251-MGMT, and U87) were irradiated with 6-MV and 10-MV X-rays from a linear accelerator in FFF- or FLAT-beam modes at dose rates in the range of 0.5-24 Gy/min. The surviving fraction (SF) as function of dose (2-12 Gy) was determined by the colony formation assay and fitted by the linear-quadratic model. For both beams (FFF or FLAT), the cells were pelleted in conical 15-ml centrifuge tubes and irradiated at 2-cm depth in a 1 x 1-cm{sup 2} area on the central axis of a 30 x 30-cm{sup 2} field. Dosimetry was performed with a 0.3-cm{sup 3} rigid ionization chamber. RBE was determined for FFF versus FLAT irradiation. The RBE of FFF at 7.3-11.3 Gy was 1.027 ± 0.013 and 1.063 ± 0.018 relative to FLAT beams for 6- and 10-MV beams, respectively, and was only significantly higher than 1 for 10 MV. Significantly increased survival rates were seen for lower dose rates (0.5 Gy/min FLAT vs. 5 Gy/min FLAT) at higher doses (11.9 Gy), while no differences were seen at dose rates ≥ 1.4 Gy/min (1.4 Gy/min FFF vs. 14 Gy/min FFF and 2.4 Gy/min FFF vs. 24 Gy/min FFF). FFF beams showed only a slightly increased RBE relative to FLAT beams in this experimental set-up, which is unlikely to result in clinically relevant differences in outcome. (orig.) [German] Die Flattening-Filter-freie (FFF) Bestrahlungstechnik findet zunehmend Verwendung, da sich die Applikationsdauer der einzelnen Fraktionen deutlich verkuerzen laesst. Aufgrund der Unterschiede im Spektrum koennte die relative biologische Wirksamkeit (RBW) von FFF jedoch hoeher sein als bei konventioneller Technik (d.h. bei

  7. Haplotypes of the HLA-G 3’ Untranslated Region Respond to Endogenous Factors of HLA-G+ and HLA-G- Cell Lines Differentially

    Science.gov (United States)

    Cagnin, Natalia F.; Sgorla de Almeida, Bibiana; Castelli, Erick C.; Carosella, Edgardo D.; Donadi, Eduardo A.; Moreau, Philippe

    2017-01-01

    The immune checkpoint HLA-G prevents maternal rejection of the fetus and contributes in cancer invasion and acceptance of allografts. The 5’ and 3’ regulatory regions of the HLA-G gene are polymorphic and balancing selection probably maintains this variability. It is proposed that nucleotide variations may affect the level of HLA-G expression. To investigate this issue we aimed to analyze how haplotypes of the 3’ untranslated region (3’UTR) with highest worldwide frequencies, namely UTR-1, UTR-2, UTR-3, UTR-4, UTR-5, UTR-18 and UTR-7, impact the expression of a luciferase reporter gene in vitro. Experiments performed with the HLA-G positive cell lines JEG-3 (choricarcinoma) and FON (melanoma), and with the HLA-G negative cell lines M8 (melanoma) and U251MG (glioblastoma) showed that the HLA-G 3’UTR polymorphism influences the response to endogenous cellular factors and may vary according to the cell type. UTR-5 and UTR-7 impact the activity of luciferase the most whereas UTR-2, UTR-3, UTR-4, and UTR-18 have intermediate impact, and UTR-1 has the lowest impact. These results corroborate the previous associations between amounts of plasma sHLA-G levels and 3’UTR haplotypes in healthy individuals and reinforce that 3’UTR typing may be a predictor of the genetic predisposition of an individual to express different levels of HLA-G. PMID:28045999

  8. ZEB2 mediates multiple pathways regulating cell proliferation, migration, invasion, and apoptosis in glioma.

    Directory of Open Access Journals (Sweden)

    Songtao Qi

    Full Text Available BACKGROUND: The aim of the present study was to analyze the expression of Zinc finger E-box Binding homeobox 2 (ZEB2 in glioma and to explore the molecular mechanisms of ZEB2 that regulate cell proliferation, migration, invasion, and apoptosis. METHODOLOGY/PRINCIPAL FINDINGS: Expression of ZEB2 in 90 clinicopathologically characterized glioma patients was analyzed by immunohistochemistry. Furthermore, siRNA targeting ZEB2 was transfected into U251 and U87 glioma cell lines in vitro and proliferation, migration, invasion, and apoptosis were examined separately by MTT assay, Transwell chamber assay, flow cytometry, and western blot. RESULTS: The expression level of ZEB2 protein was significantly increased in glioma tissues compared to normal brain tissues (P<0.001. In addition, high levels of ZEB2 protein were positively correlated with pathology grade classification (P = 0.024 of glioma patients. Knockdown of ZEB2 by siRNA suppressed cell proliferation, migration and invasion, as well as induced cell apoptosis in glioma cells. Furthermore, ZEB2 downregulation was accompanied by decreased expression of CDK4/6, Cyclin D1, Cyclin E, E2F1, and c-myc, while p15 and p21 were upregulated. Lowered expression of ZEB2 enhanced E-cadherin levels but also inhibited β-Catenin, Vimentin, N-cadherin, and Snail expression. Several apoptosis-related regulators such as Caspase-3, Caspase-6, Caspase-9, and Cleaved-PARP were activated while PARP was inhibited after ZEB2 siRNA treatment. CONCLUSION: Overexpression of ZEB2 is an unfavorable factor that may facilitate glioma progression. Knockdown ZEB2 expression by siRNA suppressed cell proliferation, migration, invasion and promoted cell apoptosis in glioma cells.

  9. Efficacy of ribavirin against malignant glioma cell lines

    Science.gov (United States)

    OGINO, AKIYOSHI; SANO, EMIKO; OCHIAI, YUSHI; YAMAMURO, SHUN; TASHIRO, SHINYA; YACHI, KAZUNARI; OHTA, TAKASHI; FUKUSHIMA, TAKAO; OKAMOTO, YUTAKA; TSUMOTO, KOUHEI; UEDA, TAKUYA; YOSHINO, ATSUO; KATAYAMA, YOICHI

    2014-01-01

    Ribavirin (1-β-D-ribofuranosy-1,2,4-triazole-3-carboxamide) has been widely administered as an antiviral agent against RNA and DNA viruses. Ribavirin, in combination with interferon, has predominantly been applied in the treatment of the hepatitis C virus infection and its potential antitumor efficacy has recently become a point of interest. The aim of the present study was to evaluate the effect of ribavirin on the growth of malignant glioma cells, to identify novel predictive genes in malignant glioma cells (by analyzing gene expression profiles) and to assess the influence of ribavirin on the cell cycle of malignant glioma cells. The present study evaluated the antitumor efficacy of ribavirin against various malignant glioma cell lines (A-172, AM-38, T98G, U-87MG, U-138MG, U-251MG and YH-13). After culturing the cells in ribavirin-containing culture medium (final concentration, 0–1,000 μM) for 72 h, the viable proliferated cells were harvested and counted. The half maximal inhibitory concentration of ribavirin, with regard to the growth of the malignant glioma cell lines, was determined from the concentration of ribavirin required for 50% growth inhibition in comparison to the untreated control cells. Furthermore, the current study identified the genes in which the gene expression levels correlated with the ribavirin sensitivity of the malignant glioma cells lines, using a high-density oligonucleotide array. Finally, cell cycle analysis was performed on the U-87MG cell line. It was identified that ribavirin inhibited the growth of all of the malignant glioma cell lines in a dose-dependent manner, although the ribavirin sensitivity varied between each cell line. Of the extracted genes, PDGFRA demonstrated the strongest positive correlation between gene expression level and ribavirin sensitivity. Cell cycle analysis of the U-87MG cell line demonstrated that ribavirin treatment induces G0/G1 arrest and thus may be an effective agent for inhibiting malignant

  10. P17.63COMBINATION THERAPY WITH TEMOZOLOMIDE, INTERFERON-BETA, AND RIBAVIRIN IN GLIOMA CELL LINES

    Science.gov (United States)

    Ochiai, Y.; Sano, E.; Yamamuro, S.; Ogino, A.; Fukushima, T.; Tsumoto, K.; Ueda, T.; Yutaka, O.; Yoshino, A.; Yoichi, K.

    2014-01-01

    INTRODUCTION: Although Temozolomide (TMZ) with radiotherapy significantly improves the survival of newly diagnosed glioblastoma although most patients develop tumor progression within 1-2 years. The Japan Clinical Oncology Group (JCOG) are ongoing a phase II randomized study to evaluate the clinical effectiveness of TMZ and Interferon-β (IFN-β) combination therapy in glioblastoma patients. Meanwhile, Ribavirin (RBV) is a standard agent of treating of chronic hepatitis C together with interferon-α. Recently, an anti-tumor effect of RBV was reported in breast cancer and chronic myelocytic leukemia. We evaluated the effect of TMZ, IFN-β, and RBV combination therapy in glioma cell lines. METHODS: Glioma cell lines used were A-172, AM-38, T98G, U-87MG, U-138MG, U-251MG, and YH-13. Glioma cell lines were cultured in an incubator for 48 hours and administered with either 1. TMZ (10 µM) + IFN-β (10 IU/ml) or 2. TMZ (10 µM) + IFN-β (10 IU/ml) + RBV (10 µM). At 72 to 96 hours post-treatment, the number of remaining glioma cells were counted to evaluate the growth-inhibitory effects of each therapy. In addition, cell cycle changes by flow cytemetry and p53 activity with western blot analysis were examined from U-87 MG cell line. RESULTS AND CONCLUSIONS: In all cell lines, the triple combination therapy enhanced the growth-inhibitory effect compared to dual combination therapy. Triple therapy led to distribution of G2/M phase of the cell cycle and accumulated p53 activety. Rivabirin enhanced antitumor effect of TMZ and IFN combination therapy in glioma cell lines.

  11. 芹菜素对胶质瘤细胞增殖抑制作用的研究

    Institute of Scientific and Technical Information of China (English)

    杨志英; 邓志刚; 伍健明; 蓝伟红

    2012-01-01

    Objective To investigate the inhibitory effect of apigenin on glioma U251 cells. Methods U251 cells were treated by apigenin with various concentrations ( 20、 40、 80 μmol/L) . Cell proliferation was measured by MTT assay on 24, 48 and 72 h. Results Apigenin inhibited the growth and proliferation of U251 cells in a dose-dependent and time-dependent manner. Inhibition of growth was observed on 24, 48 and 72 h at the concentration of 40 and 80 μmol/L, while at the concentration of 20 μ mol/L no effect was observed. Conclusion The results demonstrate that apigenin has potent inhibitory action on glioma cell growth and proliferation.%目的 探讨芹菜素对人胶质瘤细胞U251的增殖抑制作用.方法 用四甲基偶氮唑盐(MTT)比色法,检测不同浓度(20μmol/L、40μmol/L、80μmol/L)的芹菜素作用不同时间(24h、48h、72h),对人胶质瘤细胞株U251生长的影响.结果 低剂量的芹菜素(20μmol/L)无明显抑制胶质瘤U251细胞增殖的作用,而中剂量(40μmol/L)及高剂量的芹菜素(80μmol/L)能抑制胶质瘤U251细胞增殖,且抑制作用呈剂量和时间依赖性.结论 芹菜素有抑制人胶质瘤细胞U251增殖的作用.

  12. Disruption of Parallel and Converging Signaling Pathways Contributes to the Synergistic Antitumor Effects of Simultaneous mTOR and EGFR Inhibition in GBM Cells

    Directory of Open Access Journals (Sweden)

    Ravi D. Rao

    2005-10-01

    Full Text Available Elevated epidermal growth factor receptor (EGFR and mammalian target of rapamycin (mTOR signaling are known to contribute to the malignant properties of glioblastoma multiforme (GBM, which include uncontrolled cell proliferation and evasion of apoptosis. Small molecule inhibitors that target these protein kinases have been evaluated in multiple clinical trials for cancer patients, including those with GBM. Here we have examined the cellular and molecular effects of a combined kinase inhibition of mTOR (rapamycin and EGFR (EKI-785 in U87 and U251 GBM cells. Simultaneous treatment with rapamycin and EKI-785 results in synergistic antiproliferative as well as proapoptotic effects. At a molecular level, rapamycin alone significantly decreases S6 phosphorylation, whereas EKI-785 alone promotes substantially reduced signal transducer and activator of transcription (STAT3 phosphorylation. Treatment with rapamycin alone also increases Akt phosphorylation on Ser-473, but this effect is blocked by a simultaneous administration of EKI-785. Individually, EKI-785 diminishes while rapamycin promotes the binding of the translation inhibitor eukaryotic initiation factor 4E binding protein (4EBP1 to the eukaryotic translation initiation factor 4E (eIF4E. In spite of these opposing effects, the highest level of 4EBP1-eIF4E binding occurs with the combination of the two inhibitors. These results indicate that the inhibition of EGFR and mTOR has distinct as well as common signaling consequences and provides a molecular rationale forthe synergistic antitumor effects of EKI-785 and rapamycin administration.

  13. Baicalein reduces the invasion of glioma cells via reducing the activity of p38 signaling pathway.

    Directory of Open Access Journals (Sweden)

    Zhenni Zhang

    Full Text Available Baicalein, one of the major flavonids in Scutellaria baicalensis, has historically been used in anti-inflammatory and anti-cancer therapies. However, the anti-metastatic effect and related mechanism(s in glioma are still unclear. In this study, we thus utilized glioma cell lines U87MG and U251MG to explore the effect of baicalein. We found that administration of baicalein significantly inhibited migration and invasion of glioma cells. In addition, after treating with baicalein for 24 h, there was a decrease in the levels of matrix metalloproteinase-2 (MMP-2 and MMP-9 expression as well as proteinase activity in glioma cells. Conversely, the expression of tissue inhibitor of metalloproteinase-1 (TIMP-1 and TIMP-2 was increased in a dose-dependent manner. Moreover, baicalein treatment significantly decreased the phosphorylated level of p38, but not ERK1/2, JNK1/2 and PI3K/Akt. Combined treatment with a p38 inhibitor (SB203580 and baicalein resulted in the synergistic reduction of MMP-2 and MMP-9 expression and then increase of TIMP-1 and TIMP-2 expression; and the invasive capabilities of U87MG cells were also inhibited. However, p38 chemical activator (anisomycin could block these effects produced by baicalein, suggesting baicalein directly downregulate the p38 signaling pathway. In conclusion, baicalein inhibits glioma cells invasion and metastasis by reducing cell motility and migration via suppression of p38 signaling pathway, suggesting that baicalein is a potential therapeutic agent for glioma.

  14. 内源性大麻素系统与神经胶质瘤细胞增殖与凋亡的关系分析%The relationship between endocannabinoid system and glioma cell proliferation and apoptosis

    Institute of Scientific and Technical Information of China (English)

    杜向一; 闫长祥

    2014-01-01

    目的:探讨细胞实验分析内源性大麻素系统与神经胶质瘤细胞增殖与调亡的关系。方法:选择鼠C6细胞和鼠U251细胞及进行培养,采用MTT 法测定大麻素四氢大麻酚(THC)对C6细胞增殖的影响,采用DNA梯度电泳法检测C6细胞凋亡,采用Western Blotting 法检测CB1、CB2、重组人半胱天冬酶-3(caspase-3)和过氧化物酶体增殖物激活受体(PPA R )蛋白的表达。结果:大麻素受体CB1和CB2在C6细胞和U251细胞都有表达,对比差异无统计学意义(P>0.05)。不同浓度THC(0、1、10μmol/L)的细胞生长抑制率分别为0%、6.3%、29.3%,细胞凋亡率为5.2%、7.3%和12.7%,三组间的抑制与凋亡率对比差异有统计学意义(P<0.05)。 THC不同浓度组(1、10μmol/L)C6细胞中Cleaved capase-3、PPAR蛋白表达均明显升高,与空白对照组(0μmol/L)比较差异均具有统计学意义(P<0.05)。结论:内源性大麻素系统在体外能抑制鼠C6细胞的增殖和促进其凋亡,其作用的发挥与caspase-3和PPA R表达有关。%Objective:Used the cell experiments to discuss the relationship between endocannabinoid sys-tem and glioma cell proliferation and apoptosis .Methods:Selected mouse C6 cells and U251 cells were cultured , used the MTT assay to detect C6 cell proliferation by the cannabinoids THC ,used the DNA gradient gel electropho-resis assay to detect C6 cell apoptosis ,used Western Blotting assay to detect the expression of CB1 ,CB2 ,caspase-3 and the PPAR protein .Results :The CB1 and CB2 were expressed in the C6 cells and U251 cells that compared had no significant difference (P> 0 .05) .The different concentrations of THC (0 ,1 ,10 μmol /L) of cell growth in-hibition rates were 0 % ,6 .3% ,29 .3% ,and the apoptosis rate were 5 .2% ,7 .3 % and 12 .7% ,among the three groups of inhibition and apoptosis rates contrasted had significantly (P< 0 .05) .The

  15. Trichosanthin suppresses the proliferation of glioma cells by inhibiting LGR5 expression and the Wnt/β-catenin signaling pathway.

    Science.gov (United States)

    Miao, Junjie; Jiang, Yilin; Wang, Dongliang; Zhou, Jingru; Fan, Cungang; Jiao, Feng; Liu, Bo; Zhang, Jun; Wang, Yangshuo; Zhang, Qingjun

    2015-12-01

    Studies have indicated that trichosanthin (TCS), a bioactive protein extracted and purified from the tuberous root of Trichosanthes kirilowii (a well‑known traditional Chinese medicinal plant), produces antitumor effects on various types of cancer cells. However, the effects of TCS on glioma cells are poorly understood. The objective of this study was to investigate the antitumor effects of TCS on the U87 and U251 cell lines. The in vitro effects of TCS on these two cell lines were determined using a Cell Counting Kit‑8 (CCK‑8) assay, Annexin V‑FITC staining, DAPI staining, Transwell assays, terminal deoxynucleotidyl transferase‑mediated dUTP nick end‑labeling (TUNEL) assays, 5,5',6,6'‑tetrachloro‑1,1',3,3'‑tetraethyl‑imidacarbocyanine iodide (JC‑1) staining and western blotting, which was utilized to assess the expression of leucine‑rich repeat‑containing G protein‑coupled receptor 5 (LGR5) and key proteins in the Wnt/β‑catenin signaling pathway. Our data indicated that TCS inhibited the proliferation of glioma cells in a dose‑ and time‑dependent manner and played a role in inhibiting glioma cell invasion and migration. Additional investigation revealed that the expression levels of LGR5 and of key proteins in the Wnt/β‑catenin signaling pathway were markedly decreased after TCS treatment. The results suggest that TCS may induce apoptosis in glioma cells by targeting LGR5 and repressing the Wnt/β‑catenin signaling pathway. In the future, in vivo experiments should be conducted to examine the potential use of this compound as a novel therapeutic agent for gliomas.

  16. Telomerase reverse transcriptase promoter-driven expression of iodine pump genes for targeted radioiodine therapy of malignant glioma cells

    Institute of Scientific and Technical Information of China (English)

    Jian Tan; Wei Li; Peng Wang

    2011-01-01

    Radioiodine is a routine therapy for differentiated thyroid cancers. Non-thyroid cancers can intake radioiodine after transfection of the human sodium iodide symporter (hNIS) gene. The human telomerase reverse transcriptase (hTERT) promoter, an excellent tumor-specific promoter, has potential value for targeted gene therapy of glioma. We used the hTERT promoter to drive the expression of the hNIS and human thyroid peroxidase (hTPO) gene as a primary step for testing the effects of radioiodine therapy on malignant glioma. The U87 and U251 cells were co-transfected with two adenoviral vectors, in which the hNIS gene had been coupled to the hTERT promoter and the hTPO gene had been coupled to the CMV promoter, respectively. Then, we performed Western blot, 135l intake and efflux assays, and clonogenic assay with cancer cells. We also did 99mTc tumor imaging of nude mice models. After co-transfection with Ad-hTERT-hNIS and Ad-CMV-hTPO, glioma cells showed the 125l intake almost 1.5 times higher than cells transfected with Ad-hTERT-hNIS alone. Western blots revealed bands of approximately 70 kDa and 110 kDa, consistent with the hNIS and hTPO proteins. In clonogenic assay, approximately 90% of co transfected cells were killed, compared to 50% of control cells after incubated with 37 MBq of 131I. These results demonstrated that radioiodine therapy was effective in treating malignant glioma cell lines following induction of tumor-specific iodide intake by the hTERT promoter-directed hNIS expression in vitro. Co transfected hNIS and hTPO genes can result in increased intake and longer retention of radioiodine. Nude mice harboring xenografts transfected with Ad-hTERT-NIS can take 99mTc scans.

  17. Several synthetic progestins disrupt the glial cell specific-brain aromatase expression in developing zebra fish.

    Science.gov (United States)

    Cano-Nicolau, Joel; Garoche, Clémentine; Hinfray, Nathalie; Pellegrini, Elisabeth; Boujrad, Noureddine; Pakdel, Farzad; Kah, Olivier; Brion, François

    2016-08-15

    The effects of some progestins on fish reproduction have been recently reported revealing the hazard of this class of steroidal pharmaceuticals. However, their effects at the central nervous system level have been poorly studied until now. Notwithstanding, progesterone, although still widely considered primarily a sex hormone, is an important agent affecting many central nervous system functions. Herein, we investigated the effects of a large set of synthetic ligands of the nuclear progesterone receptor on the glial-specific expression of the zebrafish brain aromatase (cyp19a1b) using zebrafish mechanism-based assays. Progesterone and 24 progestins were first screened on transgenic cyp19a1b-GFP zebrafish embryos. We showed that progesterone, dydrogesterone, drospirenone and all the progesterone-derived progestins had no effect on GFP expression. Conversely, all progestins derived from 19-nortesterone induced GFP in a concentration-dependent manner with EC50 ranging from the low nM range to hundreds nM. The 19-nortestosterone derived progestins levonorgestrel (LNG) and norethindrone (NET) were further tested in a radial glial cell context using U251-MG cells co-transfected with zebrafish ER subtypes (zfERα, zfERβ1 or zfERβ2) and cyp19a1b promoter linked to luciferase. Progesterone had no effect on luciferase activity while NET and LNG induced luciferase activity that was blocked by ICI 182,780. Zebrafish-ERs competition assays showed that NET and LNG were unable to bind to ERs, suggesting that the effects of these compounds on cyp19a1b require metabolic activation prior to elicit estrogenic activity. Overall, we demonstrate that 19-nortestosterone derived progestins elicit estrogenic activity by inducing cyp19a1b expression in radial glial cells. Given the crucial role of radial glial cells and neuro-estrogens in early development of brain, the consequences of exposure of fish to these compounds require further investigation.

  18. Acetate supplementation as a means of inducing glioblastoma stem-like cell growth arrest.

    Science.gov (United States)

    Long, Patrick M; Tighe, Scott W; Driscoll, Heather E; Fortner, Karen A; Viapiano, Mariano S; Jaworski, Diane M

    2015-08-01

    Glioblastoma (GBM), the most common primary adult malignant brain tumor, is associated with a poor prognosis due, in part, to tumor recurrence mediated by chemotherapy and radiation resistant glioma stem-like cells (GSCs). The metabolic and epigenetic state of GSCs differs from their non-GSC counterparts, with GSCs exhibiting greater glycolytic metabolism and global hypoacetylation. However, little attention has been focused on the potential use of acetate supplementation as a therapeutic approach. N-acetyl-l-aspartate (NAA), the primary storage form of brain acetate, and aspartoacylase (ASPA), the enzyme responsible for NAA catalysis, are significantly reduced in GBM tumors. We recently demonstrated that NAA supplementation is not an appropriate therapeutic approach since it increases GSC proliferation and pursued an alternative acetate source. The FDA approved food additive Triacetin (glyceryl triacetate, GTA) has been safely used for acetate supplementation therapy in Canavan disease, a leukodystrophy due to ASPA mutation. This study characterized the effects of GTA on the proliferation and differentiation of six primary GBM-derived GSCs relative to established U87 and U251 GBM cell lines, normal human cerebral cortical astrocytes, and murine neural stem cells. GTA reduced proliferation of GSCs greater than established GBM lines. Moreover, GTA reduced growth of the more aggressive mesenchymal GSCs greater than proneural GSCs. Although sodium acetate induced a dose-dependent reduction of GSC growth, it also reduced cell viability. GTA-mediated growth inhibition was not associated with differentiation, but increased protein acetylation. These data suggest that GTA-mediated acetate supplementation is a novel therapeutic strategy to inhibit GSC growth.

  19. Competitive but Not Allosteric mTOR Kinase Inhibition Enhances Tumor Cell Radiosensitivity1

    Science.gov (United States)

    Hayman, Thomas J; Kramp, Tamalee; Kahn, Jenna; Jamal, Muhammad; Camphausen, Kevin; Tofilon, Philip J

    2013-01-01

    The mechanistic target of rapamycin (mTOR) is a critical kinase in the regulation of gene translation and has been suggested as a potential target for radiosensitization. The goal of this study was to compare the radiosensitizing activities of the allosteric mTOR inhibitor rapamycin with that of the competitive mTOR inhibitor PP242. On the basis of immunoblot analyses, whereas rapamycin only partially inhibited mTOR complex 1 (mTORC1) activity and had no effect on mTOR complex 2 (mTORC2), PP242 inhibited the activity of both mTOR-containing complexes. Irradiation alone had no effect on mTORC1 or mTORC2 activity. Clonogenic survival was used to define the effects of the mTOR inhibitors on in vitro radiosensitivity. In the two tumor cell lines evaluated, PP242 treatment 1 hour before irradiation increased radiosensitivity, whereas rapamycin had no effect. Addition of PP242 after irradiation also enhanced the radiosensitivity of both tumor lines. To investigate the mechanism of radiosensitization, the induction and repair of DNA double-strand breaks were evaluated according γH2AX foci. PP242 exposure did not influence the initial level of γH2AX foci after irradiation but did significantly delay the dispersal of radiation-induced γH2AX foci. In contrast to the tumor cell lines, the radiosensitivity of a normal human fibroblast cell line was not influenced by PP242. Finally, PP242 administration to mice bearing U251 xenografts enhanced radiation-induced tumor growth delay. These results indicate that in a preclinical tumor model PP242 enhances tumor cell radiosensitivity both in vitro and in vivo and suggest that this effect involves an inhibition of DNA repair. PMID:23730416

  20. Competitive but Not Allosteric mTOR Kinase Inhibition Enhances Tumor Cell Radiosensitivity.

    Science.gov (United States)

    Hayman, Thomas J; Kramp, Tamalee; Kahn, Jenna; Jamal, Muhammad; Camphausen, Kevin; Tofilon, Philip J

    2013-06-01

    The mechanistic target of rapamycin (mTOR) is a critical kinase in the regulation of gene translation and has been suggested as a potential target for radiosensitization. The goal of this study was to compare the radiosensitizing activities of the allosteric mTOR inhibitor rapamycin with that of the competitive mTOR inhibitor PP242. On the basis of immunoblot analyses, whereas rapamycin only partially inhibited mTOR complex 1 (mTORC1) activity and had no effect on mTOR complex 2 (mTORC2), PP242 inhibited the activity of both mTOR-containing complexes. Irradiation alone had no effect on mTORC1 or mTORC2 activity. Clonogenic survival was used to define the effects of the mTOR inhibitors on in vitro radiosensitivity. In the two tumor cell lines evaluated, PP242 treatment 1 hour before irradiation increased radiosensitivity, whereas rapamycin had no effect. Addition of PP242 after irradiation also enhanced the radiosensitivity of both tumor lines. To investigate the mechanism of radiosensitization, the induction and repair of DNA double-strand breaks were evaluated according γH2AX foci. PP242 exposure did not influence the initial level of γH2AX foci after irradiation but did significantly delay the dispersal of radiation-induced γH2AX foci. In contrast to the tumor cell lines, the radiosensitivity of a normal human fibroblast cell line was not influenced by PP242. Finally, PP242 administration to mice bearing U251 xenografts enhanced radiation-induced tumor growth delay. These results indicate that in a preclinical tumor model PP242 enhances tumor cell radiosensitivity both in vitro and in vivo and suggest that this effect involves an inhibition of DNA repair.

  1. Superoxide mediates direct current electric field-induced directional migration of glioma cells through the activation of AKT and ERK.

    Directory of Open Access Journals (Sweden)

    Fei Li

    Full Text Available Direct current electric fields (DCEFs can induce directional migration for many cell types through activation of intracellular signaling pathways. However, the mechanisms that bridge extracellular electrical stimulation with intracellular signaling remain largely unknown. In the current study, we found that a DCEF can induce the directional migration of U87, C6 and U251 glioma cells to the cathode and stimulate the production of hydrogen peroxide and superoxide. Subsequent studies demonstrated that the electrotaxis of glioma cells were abolished by the superoxide inhibitor N-acetyl-l-cysteine (NAC or overexpression of mitochondrial superoxide dismutase (MnSOD, but was not affected by inhibition of hydrogen peroxide through the overexpression of catalase. Furthermore, we found that the presence of NAC, as well as the overexpression of MnSOD, could almost completely abolish the activation of Akt, extracellular-signal-regulated kinase (Erk1/2, c-Jun N-terminal kinase (JNK, and p38, although only JNK and p38 were affected by overexpression of catalase. The presenting of specific inhibitors can decrease the activation of Erk1/2 or Akt as well as the directional migration of glioma cells. Collectively, our data demonstrate that superoxide may play a critical role in DCEF-induced directional migration of glioma cells through the regulation of Akt and Erk1/2 activation. This study provides novel evidence that the superoxide is at least one of the "bridges" coupling the extracellular electric stimulation to the intracellular signals during DCEF-mediated cell directional migration.

  2. Inhibition of autophagy induced by quercetin at a late stage enhances cytotoxic effects on glioma cells.

    Science.gov (United States)

    Bi, Yunke; Shen, Chen; Li, Chenguang; Liu, Yaohua; Gao, Dandan; Shi, Chen; Peng, Fei; Liu, Zhendong; Zhao, Boxian; Zheng, Zhixing; Wang, Xiaoxiong; Hou, Xu; Liu, Huailei; Wu, Jianing; Zou, Huichao; Wang, Kaikai; Zhong, Chen; Zhang, Jiakang; Shi, Changbin; Zhao, Shiguang

    2016-03-01

    Glioma is the most common primary brain tumor in the central nervous system (CNS) with high morbidity and mortality in adults. Although standardized comprehensive therapy has been adapted, the prognosis of glioma patients is still frustrating and thus novel therapeutic strategies are urgently in need. Quercetin (Quer), an important flavonoid compound found in many herbs, is shown to be effective in some tumor models including glioma. Recently, it is reported that adequate regulation of autophagy can strengthen cytotoxic effect of anticancer drugs. However, it is not yet fully clear how we should modulate autophagy to achieve a satisfactory therapeutic effect. 3-Methyladenine (3-MA) and Beclin1 short hairpin RNA (shRNA) were used to inhibit the early stage of autophage while chloroquine (CQ) to inhibit the late stage. MTT assay was implemented to determine cell viability. Transmission electron microscopy, western blot, and immunohistochemistry were adopted to evaluate autophagy. Western blot, flow cytometry, and immunohistochemistry were used to detect apoptosis. C6 glioma xenograft models were established to assess the therapeutic effect (the body weight change, the median survival time, and tumor volume) in vivo. Quercetin can inhibit cell viability and induce autophagy of U87 and U251 glioma cells in a dose-dependent manner. Inhibition of early-stage autophagy by 3-MA or shRNA against Beclin1 attenuated the quercetin-induced cytotoxicity. In contrast, suppression of autophagy at a late stage by CQ enhanced the anti-glioma efficiency of quercetin. Therapeutic effect of quercetin for malignant glioma can be strengthened by inhibition of autophagy at a late stage, not initial stage, which may provide a novel opportunity for glioma therapy.

  3. Pitfalls of the MTT assay: Direct and off-target effects of inhibitors can result in over/underestimation of cell viability.

    Science.gov (United States)

    Stepanenko, A A; Dmitrenko, V V

    2015-12-15

    The MTT assay (to a less degree MTS, XTT or WST) is a widely exploited approach for measuring cell viability/drug cytotoxicity. MTT reduction occurs throughout a cell and can be significantly affected by a number of factors, including metabolic and energy perturbations, changes in the activity of oxidoreductases, endo-/exocytosis and intracellular trafficking. Over/underestimation of cell viability by the MTT assay may be due to both adaptive metabolic and mitochondrial reprogramming of cells subjected to drug treatment-mediated stress and inhibitor off-target effects. Previously, imatinib, rottlerin, ursolic acid, verapamil, resveratrol, genistein nanoparticles and some polypeptides were shown to interfere with MTT reduction rate resulting in inconsistent results between the MTT assay and alternative assays. Here, to test the under/overestimation of viability by the MTT assay, we compared results derived from the MTT assay with the trypan blue exclusion assay after treatment of glioblastoma U251, T98G and C6 cells with three widely used inhibitors with the known direct and side effects on energy and metabolic homeostasis - temozolomide (TMZ), a DNA-methylating agent, temsirolimus (TEM), an inhibitor of mTOR kinase, and U0126, an inhibitor of MEK1/2 kinases. Inhibitors were applied shortly as in IC50 evaluating studies or long as in studies focusing on drug resistance acquisition. We showed that over/underestimation of cell viability by the MTT assay and its significance depends on a cell line, a time point of viability measurement and other experimental parameters. Furthermore, we provided a comprehensive survey of factors that should be accounted in the MTT assay. To avoid result misinterpretation, supplementation of the tetrazolium salt-based assays with other non-metabolic assays is recommended.

  4. Curcumin regulation of glioma cell proliferation and apoptosis through Wnt/β-catenin signaling pathway: an experimental study%姜黄素通过Wnt/β-catenin信号通路调控胶质瘤细胞增殖和凋亡的实验研究

    Institute of Scientific and Technical Information of China (English)

    马光涛; 张燕; 李晨龙; 郄福忠; 曹振宇; 蒋传路

    2015-01-01

    作用胶质瘤细胞后,Wnt/β-catenin通路活性明显受到抑制(P<0.01).结论 姜黄素可能通过下调Wnt/β-catenin通路抑制胶质瘤细胞增殖并促进凋亡.%Objective To investigate the effects of curcumin on glioma cell proliferation and apoptosis through Wnt/β-catenin signaling pathway.Methods The research objects were the human glioblastoma U251 cell lines.The experiment was divided into either a blank control group or a curcumin experiment group (the experiment concentrations were 10 μmol/L and 20 μmol/L respectively).The cell toxicity test was used to study cellular toxic effect of curcumin on U251 glioma.Four methyl thiazolyl tetrazolium (MTT) assay was used to observe the cell proliferative capacity; the caspase-3 activity assay and flow cytometry (FCM) test were used to detect cell apoptosis ; flow cytometry was used detect the cell cycle;real-time quantitative PCR,Western-blotting,and immunofluorescence assay were used to detect the expression levels of intracellular β-catenin and c-myc.The luciferase assay was used to detect the changes of Wnt/β-catenin signaling pathway activity after the effects of curcumin.Results With the increased effect concentration of curcumin,the cytotoxicity of U251 glioma cells enhanced.In the curcumin experimental group,when the concentrations were 5,10,20,and 40 μmol/L,the cells activities were 88.55% ±2.35%,62.78% ±3.35%,35.17% ±2.05%,and 7.47% ± 1.92%,respectively (P <0.05),and the effect of proliferation inhibition enhanced obviously.IC50 of the measured curcumin effect for 24 h was 16.32 μmol/L,therefore,the concentrations of 10 μmo]/L and 20 μmol/L in the curcumin experimental group were chosen; the relative activities of caspase-3 in the experimental group (10 μmol/L and 20 μmol/L) were 3.64% ± 1.49% and 5.41% ±0.36% respectively.Compared with the control group 0.91% ± 0.62%,the activities enhanced significantly (P < 0.05).After flow cytometry was

  5. R132H mutation in IDH1 gene reduces proliferation, cell survival and invasion of human glioma by downregulating Wnt/β-catenin signaling.

    Science.gov (United States)

    Cui, Daming; Ren, Jie; Shi, Jinlong; Feng, Lijing; Wang, Ke; Zeng, Tao; Jin, Yi; Gao, Liang

    2016-04-01

    Mutations in the isocitrate dehydrogenase 1 (IDH1) gene commonly occur in gliomas. Remarkably, the R132H mutation in IDH1 (IDH1-R132H) is associated with better prognosis and increased survival than patients lacking this mutation. The molecular mechanism underlying this phenomenon is largely unknown. In this study, we investigated potential cross-talk between IDH1-R132H and Wnt/β-catenin signaling in regulating the cellular properties of human glioma. Although aberrant nuclear accumulation of β-catenin is linked to the malignant progression of gliomas, its association with IDH1 remains unknown. We identified an inverse correlation between IDH1-R132H and the expression and activity of β-catenin in human gliomas. In addition, overexpression of IDH1-R132H in glioblastoma cell lines U87 and U251 led to reduced cell proliferation, migration and invasion, accompanied by increased apoptosis. At the molecular level, we detected a significant reduction in the expression, nuclear accumulation and activity of β-catenin following overexpression of IDH1-R132H. A microarray-based comparison of gene expression indicated that several mediators, effectors and targets of Wnt/β-catenin signaling are downregulated, while negative regulators are upregulated in IDH1-R132H gliomas. Further, overexpression of β-catenin in IDH1-R132H glioma cells restored the cellular phenotype induced by this mutation. Specifically, β-catenin abrogated the decrease in proliferation, invasion and migration, and the increase in apoptosis, triggered by overexpression of IDH1-R132H. Finally, we demonstrate that xenografts of IDH1-R132H overexpressing U87 cells can significantly decrease the growth of tumors in vivo. Altogether, our results strongly suggest that the R132H mutation in IDH1 serves a tumor suppressor function in human glioma by negatively regulating Wnt/β-catenin signaling.

  6. Disruption of Parallel and Converging Signaling Pathways Contributes to the Synergistic Antitumor Effects of Simultaneous mTOR and EGFR Inhibition in GBM Cells1

    Science.gov (United States)

    Rao, Ravi D; Mladek, Ann C; Lamont, Jeffrey D; Goble, Jennie M; Erlichman, Charles; James, C David; Sarkaria, Jann N

    2005-01-01

    Abstract Elevated epidermal growth factor receptor (EGFR) and mammalian target of rapamycin (mTOR) signaling are known to contribute to the malignant properties of glioblastoma multiforme (GBM), which include uncontrolled cell proliferation and evasion of apoptosis. Small molecule inhibitors that target these protein kinases have been evaluated in multiple clinical trials for cancer patients, including those with GBM. Here we have examined the cellular and molecular effects of a combined kinase inhibition of mTOR (rapamycin) and EGFR (EKI-785) in U87 and U251 GBM cells. Simultaneous treatment with rapamycin and EKI-785 results in synergistic antiproliferative as well as proapoptotic effects. At a molecular level, rapamycin alone significantly decreases S6 phosphorylation, whereas EKI-785 alone promotes substantially reduced signal transducer and activator of transcription (STAT3) phosphorylation. Treatment with rapamycin alone also increases Akt phosphorylation on Ser-473, but this effect is blocked by a simultaneous administration of EKI-785. Individually, EKI-785 diminishes while rapamycin promotes the binding of the translation inhibitor eukaryotic initiation factor 4E binding protein (4EBP1) to the eukaryotic translation initiation factor 4E (eIF4E). In spite of these opposing effects, the highest level of 4EBP1-eIF4E binding occurs with the combination of the two inhibitors. These results indicate that the inhibition of EGFR and mTOR has distinct as well as common signaling consequences and provides a molecular rationale for the synergistic antitumor effects of EKI-785 and rapamycin administration. PMID:16242075

  7. Cells

    Directory of Open Access Journals (Sweden)

    Zhao-Hui Jin

    2012-11-01

    Full Text Available As cancer stem cells (CSCs are postulated to play critical roles in cancer development, including metastasis and recurrence, CSC imaging would provide valuable information for cancer treatment and lead to CSC-targeted therapy. To assess the possibility of in vivo CSC targeting, we conducted basic studies on radioimmunotargeting of cancer cells positive for CD133, a CSC marker recognized in various cancers. Antibodies against CD133 were labeled with 125I, and their in vitro cell binding properties were tested. Using the same isotype IgG as a control, in vivo biodistribution of the labeled antibody retaining immunoreactivity was examined in mice bearing an HCT116 xenograft in which a population of the cancer cells expressed CD133. Intratumoral distribution of the labeled antibody was examined and compared to the CD133 expression pattern. The 125I-labeled anti-CD133 antibody showed a modest but significantly higher accumulation in the HCT116 xenograft compared to the control IgG. The intratumoral distribution of the labeled antibody mostly overlapped with the CD133 expression, whereas the control IgG was found in the area close to the necrotic tumor center. Our results indicate that noninvasive in vivo targeting of CSCs could be possible with radiolabeled antibodies against cell membrane markers.

  8. Influences of surface coatings and components of FePt nanoparticles on the suppression of glioma cell proliferation

    Directory of Open Access Journals (Sweden)

    Sun H

    2012-07-01

    Full Text Available Haiming Sun,1,* Xiaohui Chen,2,* Dan Chen,1 Mingyan Dong,1 Xinning Fu,1 Qian Li,1 Xi Liu,1 Qingzhi Wu,1 Tong Qiu,1 Tao Wan,1 Shipu Li11State Key Laboratory of Advanced Technology for Materials Synthesis and Processing and Biomedical Materials and Engineering Center, Wuhan University of Technology, Wuhan, China; 2Department of Prosthetics, School of Stomatology, Wuhan University, Wuhan, China*Both authors contributed equally to this workAbstract: Malignant gliomas are primary brain tumors with high rates of morbidity and mortality; they are the fourth most common cause of cancer death. Novel diagnostic and therapeutic techniques based on nanomaterials provide promising options in the treatment of malignant gliomas. In order to evaluate the potential of FePt nanoparticles (NPs for malignant glioma therapy, FePt NPs with different surface coatings and components were tunably synthesized using oleic acid/oleylamine (OA/OA and cysteines (Cys as the capping agents, respectively. The samples were characterized using X-ray diffraction, transmission electron microscopy (TEM, X-ray photon spectroscopy, Fourier transform infrared spectroscopy, atomic absorption spectrum, and zeta potential. The influence of the surface coatings and components of the FePt NPs on the proliferation of glioma cells was assessed through MTT assay and TEM observation using three typical glioma cell lines (glioma U251 cells, astrocytoma U87 cells, and neuroglioma H4 cells as in vitro models. The results showed that the proliferation of glioma cells was significantly suppressed by lipophilic FePt-OA/OA NPs in a time- and/or dose-dependent manner, while no or low cytotoxic effects were detected in the case of hydrophilic FePt-Cys NPs. The IC50 value of FePt-OA/OA NPs on the three glioma cell lines was approximately 5–10 µg mL-1 after 24 hours’ incubation. Although the cellular uptake of FePt NPs was confirmed regardless of the surface coatings and components of the FePt NPs

  9. Sp1 regulates Raf/MEK/ERK-induced p21(CIP1) transcription in TP53-mutated cancer cells.

    Science.gov (United States)

    Karkhanis, Mansi; Park, Jong-In

    2015-03-01

    We previously reported that the upregulation of mortalin, an Hsp70 family chaperone, is important for B-Raf(V600E) tumor cells to bypass p21(CIP1) expression, which is activated as a tumor-suppressive mechanism in response to aberrant MEK/ERK activation (Wu et al., 2013). Interestingly, mortalin depletion induced p21(CIP1) transcription not only in wild-type TP53 but also in TP53-mutated B-Raf(V600E) cancer cells, suggesting the presence of an additional mechanism for p21(CIP1) regulation. In the present study, using luciferase reporter truncation analysis in a TP53-mutated B-Raf(V600E) cancer cell line, SK-MEL28, we identified a proximal p21(CIP1) promoter region responsive to mortalin depletion. Interestingly, when Sp1-like cis-elements in this promoter region were mutagenized, the p21(CIP1) promoter luciferase reporter was no longer responsive to mortalin depletion. Consistent with this, our ChIP analysis revealed that mortalin knockdown could induce Sp1 binding to p21(CIP1) promoter in a MEK/ERK-dependent manner. Moreover, RNA interference of Sp1 substantially attenuated p21(CIP1) expression induced by mortalin depletion in SK-MEL28 cells. Consistent with this observation in SK-MEL28 cells, Sp1 was necessary for the tamoxifen-regulated ∆Raf-1:ER to induce p21(CIP1) transcription in U251 cells, in which TP53 is mutated. However, in contrast, Sp1 was not necessary for ∆Raf-1:ER to induce p21(CIP1) transcription in LNCaP cells, in which TP53 is wild type. These data suggest that Sp1 may address TP53-independent p21(CIP1) transcription in Raf/MEK/ERK-activated cancer cells and that its requirement in Raf/MEK/ERK-induced p21(CIP1) transcription is subject to TP53 status.

  10. 脑胶质瘤细胞顺铂耐药分子标志物筛选%A Screen for Molecular Markers of Cisplatin Resistance in Glioma Cells

    Institute of Scientific and Technical Information of China (English)

    崔磊; 付军; 吴浩强; 彭颂先; 陈忠平

    2009-01-01

    背景与目的:顺铂是神经肿瘤化疗常用药物之一,耐药是疗效不佳原因之一.遗传学改变可以影响肿瘤细胞对化疗的敏感性.本研究旨在利用芯片-基因组杂交技术筛选胶质瘤细胞中与顺铂耐药相关的分子标志物.方法:用芯片-基因组杂交技术对我们先前采用顺铂剂量梯度爬升诱导的对顺铂高度耐药的U251/CP2细胞(IC50为76.5 μg/mL)和亲代细胞U251细胞(IC10为1.2 μg/ml)筛选与顺铂耐药相关的分子标志物.RT-PCR和实时荧光定量PCR用来对结果进行验证.结果:补体因子H相关蛋白1基因(CFHRl)和补体因子H相关蛋白3基因(CFHR3)在U251细胞中至少各自缺失了一个拷贝,在U251/CP2细胞中完全缺失.IL-7基因在U251/CP2细胞中的拷贝数为U251细胞的2~3倍.结论:CFHR1、CFHR3和IL-7基因可能与胶质瘤对顺铂耐药有关.

  11. 人钠/碘同向转运体基因转染胶质瘤细胞介导放射性碘治疗的研究%Transfer of the sodium/iodide symporter gene into gliomas for radioiodine therapy in vitro

    Institute of Scientific and Technical Information of China (English)

    谭建; 李玮; 刘晓华; 肖茜; 贾强; 李宁

    2008-01-01

    Objective The most frequent brain tumors are the gliomas.Glioblastomas arc largely incurable secondary to their rapid,aggressive and diffusely infiltrative growth pattern and hypervascularity.This study,aimed at investigating the possibility of transecting human sodium/iodide symporter(hNIS)gene into human glioma cell lines to facilitate radioactive iodide treatment in vitro.Methods Transecting hNIS gene into human glioma cell lines U251 was performed by recombinant expression plasmids with lipofectamine 2000-plasmid complexes.The hNIS gene cell lines with stable expression(hNIS-U251)were selected through G418 antibiotic constraint.The hNIS-U251 gene cell lines were then evaluated for their biologic functions,including 125I uptake assay.125 I influx-course.125I-efflux-course.131I inhibitory effect on cellular proliferation by 3-(4,5-dimethylthiazol-2-y1)-2,5-diphenylte-trazolium bromide(MTT)assay and flow cytometer.Results We were successful in transecting hNIS gene into human glioma cell lines by recombinant expression plasmids.and were able to obtain hNIS gene cell lines(hNIS-U251)with stable expression.The hNIS-U251 cell lines could intake and bind radioactive iodide by hNIS gene.The uptakes of125 Iwere 117 fold higher in hNIS-U251 cell lines than U251 cell lines[(50 469.88±997.29),(432.92±89.28)counts·min-1,respectively ].And the proliferation index of hNIS-U251 cell lines was lower than U251 cell lines after incubating with 131I.Conclusion The hNIS gene with stable gene expression (hNIS-U251)cell lines could be labeled by 131I with a high efficiency,thereby may function effectively in the treatment of glioma-related brain tumors.%目的 在体外细胞实验中证明转染人钠/碘同向转运体(hNIS)基因介导放射性碘治疗胶质瘤是有效的.方法 以脂质体转染法、用重组质粒将hNIS基因转染至人胶质瘤细胞株U251中.经过G418硫酸盐筛选获得稳定表达hNIS的细胞株(hNIS-U251),然后进行体外摄125I

  12. Specific targeting of gliomas with multifunctional superparamagnetic iron oxide nanoparticle optical and magnetic resonance imaging contrast agents

    Institute of Scientific and Technical Information of China (English)

    Xiang-xi MENG; Jia-qi WAN; Meng JING; Shi-guang ZHAO; Wei CAI; En-zhong LIU

    2007-01-01

    Aim: To determine whether glioma cells can be specifically and efficiently tar- geted by superparamagnetic iron oxide nanoparticle (SPIO)-fluorescein isothiocyanate (FITC)-chlorotoxin (SPIOFC) that is detectable by magnetic reso- nance imaging (MRI) and optical imaging. Methods: SPIOFC was synthesized by conjugating SPIO with FITC and chlorotoxin. Glioma cells (human U251-MG and rat C6) were cultured with SPIOFC and SPIOF (SPIO-FITC), respectively. Neural cells were treated with SPIOFC as the control for SPIOFC-targeted glioma cells. The internalization of SPIOFC by glioma cells was assessed by MRI and was quantified using inductively-coupled plasma emission spectroscopy. The optical imaging ability of SPIOFC was evaluated by confocal laser scanning microscopy. Results: Iron per cell of U251 (72.5±1.8 pg) and C6 (74.9±2.2 pg) cells cultured with SPIOFC were significantly more than those of U251 (6.6±1.0 pg) and C6 (7.1±0.8 pg) cells incubated with SPIOF. The T2 signal intensity of U251 and C6 cells cultured with SPIOFC (233.6±25.9 and 211.4±17.2, respectively) were substantially lower than those of U251 and C6 cells incubated with SPIOF (2275.3±268.6 and 2342.7±222.4, respectively). Moreover, there were significant differences in iron per cell and T2 signal intensity between SPIOFC-treated neural cells (1.3±0.3; 2533.6±199.2) and SPIOFC-treated glioma cells. SPIOFC internalized by glioma cells exhibited green fluorescence by confocal laser scanning microscopy. Conclusion: SPIOFC is suitable for the specific and efficient targeting of glioma cells. MRI and optical imaging in conjunction with SPIOFC can differentiate glioma cells from normal brain tissue cells.

  13. Effects of adenylate cyclase-associated protein 1 on cell migration, invasion and adhesion of human brain glioma cells%腺苷酸环化酶相关蛋白1对人脑胶质瘤细胞迁移、侵袭和黏附的影响

    Institute of Scientific and Technical Information of China (English)

    崔晨晨; 朱一硕; 时猛; 张磊; 余进松; 陈晨; 范月超

    2016-01-01

    目的 探讨腺苷酸环化酶相关蛋白1(CAP1)对人脑胶质瘤细胞株U87、U251迁移、侵袭和黏附的影响及其机制.方法 运用小干扰RNA(siRNA)技术分别转染U87、U251细胞,Westernblot检测CAP1、MMP-2、MMP-9、黏着斑激酶(FAK)和含有酪氨酸激酶活性的Src的表达.应用细胞划痕实验及Transwell迁移、侵袭实验检测U87、U251细胞的迁移和侵袭能力.应用细胞黏附实验检测细胞黏附能力.结果 与阴性对照组比较,CAP1-siRNA组U87、U251细胞中CAP1蛋白表达量降低,MMP-2、MMP-9、FAK和Src的蛋白表达量均减少(P<0.05).CAP1-siRNA组较阴性对照组细胞的迁移能力降低(P<0.05).沉默CAP1后,U87、U251细胞的迁移、侵袭能力下降(P<0.05).CAP1 siRNA组黏附细胞个数少于阴性对照组(P<o.05).结论 CAP1-siRNA靶向干扰了CAP1的表达,同时下调MMP-2、MMP-9、FAK和Src的表达.下调CAP1的表达水平能够显著降低人脑胶质瘤细胞株U87、U251迁移、侵袭和黏附能力.

  14. Overexpression of CDC2/CyclinB1 in gliomas, and CDC2 depletion inhibits proliferation of human glioma cells in vitro and in vivo

    Directory of Open Access Journals (Sweden)

    Wang Ai-Dong

    2008-01-01

    Full Text Available Abstract Background Gliomas are the most common and aggressive primary brain tumors for which unfortunately no effective treatment modalities exist despite advances in molecular biology as the knowledge base to unravel the extremely complex molecular mechanisms of tumorigenesis is limited. In this study an attempt has been made to understand the molecular pathological basis of tumorigenesis which led to an identification of an oncogene, CDC2, and an epigenetic strategy has been evaluated to control the tumorigensis by downregulating this oncogene. Methods Tissue microarrays were utilized to investigate the expression of genes in a large number of tumor samples and to identify overexpressed genes which could be potentially causing tumorigenesis. Retroviral vectors expressing short hairpin RNAs (shRNAs targeted against CDC2 were designed and transducted into human glioma cell line ex vivo in order to downregulate the expression of CDC2. Real-Time PCR was used to determine the level of CDC2 mRNA. Western Blotting was used to determine the level of expression of CDC2 protein as measure to quantify down regulation of CDC2 expression along with use of flow cytometry to investigate effect of shRNAs on cell cycles and detection of apoptosis. Following ex vivo study, viral particles containing small interfering RNA for CDC2 were subsequently injected into xenogeneic graft tumor of nude mice and the weight of human glioma xenografts, survival and resulting phenotypic changes of target gene were investigated. Results Human glioma tissue microarrays indicated the positive expression rates of CDC2/CyclinB1 with a positive correlation with pathologic grades (r = 0.982, r = 0.959, respectively. Retroviral vectors expressing short hairpin RNAs (shRNAs against CDC2 caused efficient deletion of CDC2, cellular G2/M arrest concluding in apoptosis and inhibition of proliferation in human glioma cells U251 and SHG-44 cell lines ex vivo. And the viral particles

  15. Mechanism by which interferon reduces the resistance of MGMT positive glioma stem cells to temozolomide%干扰素抗MGMT阳性胶质瘤干细胞替莫唑胺的耐药机制

    Institute of Scientific and Technical Information of China (English)

    苏辉; 刘兆玮; 杜红利; 乔艳梅

    2015-01-01

    OBJECTIVE:To investigate the role of interferon to increase the sensibilization of MGMT positive glioma stem cel s to temozolomide in vitro. METHODS:Glioma cel lines, U251 and SKMG-4, were induced by suspended cloning bal formation method to harvest MGMT positive glioma stem cel s, U251G and SKMG-4G. Cel counting kit-8 assay was used to detect the kil ing effect of interferonα/βcombined with temozolomide on MGMT positive glioma stem cel s. RT-PCR and western blot assay were employed to determine the expression of MGMT and nuclear factorκB in MGMT positive glioma stem cel s. RESULTS AND CONCLUSION:Western blot results showed positive expression of MGMT in U251G and SKMG-4G cel s at protein levels. After intervention with interferonα/β, the mRNA expression of MGMT and nuclear factorκB in SKMG-4G and U251G cel s was reduced significantly, and then further decreased after temozolomide treatment. These findings indicate that interferonα/βcan remarkably strengthen the kil ing effect of temozolomide on MGMT positive glioma stem cel s.%背景:临床对胶质瘤患者进行治疗的过程中容易出现耐药现象,研究发现,MGMT是胶质瘤表达的一种多药耐药基因。  目的:探讨干扰素增加替莫唑胺对MGMT阳性胶质瘤干细胞的增敏作用。  方法:采用“悬浮克隆球形成法”对胶质瘤细胞株U251、SKMG-4进行诱导,获得MGMT阳性的胶质瘤干细胞U251G、SKMG-4G。应用CCK-8法检测干扰素α/β联合替莫唑胺对MGMT阳性胶质瘤干细胞的杀伤效应;RT-PCR和Western blot检测预用干扰素α/β后MGMT阳性胶质瘤干细胞MGMT、NF-κB表达情况。结果与结论:经Western blot检测,胶质瘤干细胞U251G、SKMG-4G中MGMT蛋白呈阳性表达。采用预用干扰素α/β,然后添加替莫唑胺方式,提高了替莫唑胺的化疗敏感性,杀伤效应显著提高。使用干扰素α/β之后,SKMG-4G和U251G MGMT、NF-κB mRNA和蛋白表达均显著降低,联

  16. Pten Regulates Epithelial Cytodifferentiation during Prostate Development

    DEFF Research Database (Denmark)

    Lokody, Isabel B; Francis, Jeffrey C; Gardiner, Jennifer R;

    2015-01-01

    Gene expression and functional studies have indicated that the molecular programmes involved in prostate development are also active in prostate cancer. PTEN has been implicated in human prostate cancer and is frequently mutated in this disease. Here, using the Nkx3.1:Cre mouse strain and a genetic...... deletion approach, we investigate the role of Pten specifically in the developing mouse prostate epithelia. In contrast to its role in other developing organs, this gene is dispensable for the initial developmental processes such as budding and branching. However, as cytodifferentiation progresses...... that are shared with Pten mutant prostate cancer models, including a decrease in androgen receptor regulated genes. In depth analysis of the phenotype of these mice during development revealed that loss of Pten leads to the precocious differentiation of epithelial cells towards a luminal cell fate. This study...

  17. Transposon mutagenesis identifies genes that cooperate with mutant Pten in breast cancer progression

    Science.gov (United States)

    Rangel, Roberto; Lee, Song-Choon; Hon-Kim Ban, Kenneth; Guzman-Rojas, Liliana; Mann, Michael B.; Newberg, Justin Y.; McNoe, Leslie A.; Selvanesan, Luxmanan; Ward, Jerrold M.; Rust, Alistair G.; Chin, Kuan-Yew; Black, Michael A.; Jenkins, Nancy A.; Copeland, Neal G.

    2016-01-01

    Triple-negative breast cancer (TNBC) has the worst prognosis of any breast cancer subtype. To better understand the genetic forces driving TNBC, we performed a transposon mutagenesis screen in a phosphatase and tensin homolog (Pten) mutant mice and identified 12 candidate trunk drivers and a much larger number of progression genes. Validation studies identified eight TNBC tumor suppressor genes, including the GATA-like transcriptional repressor TRPS1. Down-regulation of TRPS1 in TNBC cells promoted epithelial-to-mesenchymal transition (EMT) by deregulating multiple EMT pathway genes, in addition to increasing the expression of SERPINE1 and SERPINB2 and the subsequent migration, invasion, and metastasis of tumor cells. Transposon mutagenesis has thus provided a better understanding of the genetic forces driving TNBC and discovered genes with potential clinical importance in TNBC. PMID:27849608

  18. Downregulation of uPAR and cathepsin B induces apoptosis via regulation of Bcl-2 and Bax and inhibition of the PI3K/Akt pathway in gliomas.

    Directory of Open Access Journals (Sweden)

    Ramarao Malla

    Full Text Available BACKGROUND: Glioma is the most commonly diagnosed primary brain tumor and is characterized by invasive and infiltrative behavior. uPAR and cathepsin B are known to be overexpressed in high-grade gliomas and are strongly correlated with invasive cancer phenotypes. METHODOLOGY/PRINCIPAL FINDINGS: In the present study, we observed that simultaneous downregulation of uPAR and cathepsin B induces upregulation of some pro-apoptotic genes and suppression of anti-apoptotic genes in human glioma cells. uPAR and cathepsin B (pCU-downregulated cells exhibited decreases in the Bcl-2/Bax ratio and initiated the collapse of mitochondrial membrane potential. We also observed that the broad caspase inhibitor, Z-Asp-2, 6-dichlorobenzoylmethylketone rescued pCU-induced apoptosis in U251 cells but not in 5310 cells. Immunoblot analysis of caspase-9 immunoprecipitates for Apaf-1 showed that uPAR and cathepsin B knockdown activated apoptosome complex formation in U251 cells. Downregulation of uPAR and cathepsin B also retarded nuclear translocation and interfered with DNA binding activity of CREB in both U251 and 5310 cells. Further western blotting analysis demonstrated that downregulation of uPAR and cathepsin B significantly decreased expression of the signaling molecules p-PDGFR-β, p-PI3K and p-Akt. An increase in the number of TUNEL-positive cells, increased Bax expression, and decreased Bcl-2 expression in nude mice brain tumor sections and brain tissue lysates confirm our in vitro results. CONCLUSIONS/SIGNIFICANCE: In conclusion, RNAi-mediated downregulation of uPAR and cathepsin B initiates caspase-dependent mitochondrial apoptosis in U251 cells and caspase-independent mitochondrial apoptosis in 5310 cells. Thus, targeting uPAR and cathepsin B-mediated signaling using siRNA may serve as a novel therapeutic strategy for the treatment of gliomas.

  19. IKKε通过E-cadherin调控人脑胶质瘤迁移和侵袭能力的实验研究%Experimental research of IKKε through E-cadherin regulation of the human brain glioma migration and invasion ability

    Institute of Scientific and Technical Information of China (English)

    周西广; 杨毅; 路捷; 南阳; 甄英伟; 俞凯; 王广秀; 贾志凡; 康春生

    2016-01-01

    Objective To investigate the effect of IKKε in glioma cells on the regulation of Ecadherin expression and cell migration and invasion ability.Methods The IKKε overexpression vectors and shRNA-IKKε lentivirus were constructed.The TP483 glioma cell lines were transfected by the IKKε overexpression plasmid.The expression level of IKKε in glioma cells was upregulated.The U251 and U138 glioma cell lines were transfected by the shRNA-IKKε lentivirus,IKKε expression level in glioma cells was downregulated.The expression levels of IKKε and E-cadherin in cells were detected by RT-PCR and Western blot.The expression changes of IKKε and E-cadherin after transfecting were observed by using the immunofluorescence assay.The cell migration and invasion abilities were detected by using the scratch test and Transwell assay.Results Compared with the non-transfected group (TP483 control group),the expression level of IKKε protein increased (P =0.000),and the expression level of E-cadherin protein decreased (P =0.000) in the transfected IKKε expression plasmid group (TP483 treaed group).In the glioma cells transfected IKKε shRNA(the U251 treated group and the U138 treated group),the expression level of IKKε protein decreased significantly compared with the non-transfected group (the U251 treated group and the U138 treated group;all P < 0.05).At the same time,the expression levels of E-cadherin protein in each treated group were all increased compared with the control group (P < 0.05).The scratch repair rate of the TP483 treated group was higher than that of the control group (56.39 ± 0.93% vs.46.43 ± 1.68%;P =0.035).After transfection of overexpression plasmid for 24 h,the number of TP483 cells passing through the filter membrane increased compared with the control group (55.8 ± 6.0 vs.24.6 ± 2.3;P =0.000).The scratch repair rates of the U251 and U138 treated groups decreased compared with their respective control groups (the U251 treated group:50.40 ± 1.09

  20. Detection of Hypoxia in Human Brain Tumor Xenografts Using a Modified Comet Assay

    Directory of Open Access Journals (Sweden)

    Jingli Wang

    2003-07-01

    Full Text Available We used the standard comet assay successfully to generate in vitro dose-response curves under oxic and hypoxic conditions. We then made mixtures of cells that had been irradiated with 3 and 9 Gy of X-rays to simulate two subpopulations in a tumor, but efforts to accurately detect and quantify the subpopulations using the standard comet assay were unsuccessful. Therefore, we investigated a modified comet assay to determine whether it could be used for measuring hypoxia in our model systems. U251 MG cells were grown as subcutaneous tumors in athymic mice; U251 MG and U87 MG cells were grown as intracerebral (i.c. tumors in athymic rats. Animals were injected with RSU 1069, irradiated, and euthanized. Tumors and normal brains were removed, and the cells were analyzed using a modified comet assay. Differences in comet tail moment distributions between tumor and contralateral normal brain, using tail moments at either the 25th or 50th percentile in each distribution, were taken as measures of the degree of tumor hypoxia. For U251 MG tumors, there was a positive relationship between tumor size and the degree of hypoxia, whereas preliminary data from U87 MG i.c. tumors showed less hypoxia and no apparent relationship between tumor size and hypoxia.

  1. c-Src and neural Wiskott-Aldrich syndrome protein (N-WASP promote low oxygen-induced accelerated brain invasion by gliomas.

    Directory of Open Access Journals (Sweden)

    Zhuo Tang

    Full Text Available Malignant gliomas remain associated with poor prognosis and high morbidity because of their ability to invade the brain; furthermore, human gliomas exhibit a phenotype of accelerated brain invasion in response to anti-angiogenic drugs. Here, we study 8 human glioblastoma cell lines; U251, U87, D54 and LN229 show accelerated motility in low ambient oxygen. Src inhibition by Dasatinib abrogates this phenotype. Molecular discovery and validation studies evaluate 46 molecules related to motility or the src pathway in U251 cells. Demanding that the molecular changes induced by low ambient oxygen are reversed by Dasatinib in U251 cells, identifies neural Wiskott-Aldrich syndrome protein (NWASP, Focal adhesion Kinase (FAK, [Formula: see text]-Catenin, and Cofilin. However, only Src-mediated NWASP phosphorylation distinguishes the four cell lines that exhibit enhanced motility in low ambient oxygen. Downregulating c-Src or NWASP by RNA interference abrogates the low-oxygen-induced enhancement in motility by in vitro assays and in organotypic brain slice cultures. The findings support the idea that c-Src and NWASP play key roles in mediating the molecular pathogenesis of low oxygen-induced accelerated brain invasion by gliomas.

  2. c-Src and neural Wiskott-Aldrich syndrome protein (N-WASP) promote low oxygen-induced accelerated brain invasion by gliomas.

    Science.gov (United States)

    Tang, Zhuo; Araysi, Lita M; Fathallah-Shaykh, Hassan M

    2013-01-01

    Malignant gliomas remain associated with poor prognosis and high morbidity because of their ability to invade the brain; furthermore, human gliomas exhibit a phenotype of accelerated brain invasion in response to anti-angiogenic drugs. Here, we study 8 human glioblastoma cell lines; U251, U87, D54 and LN229 show accelerated motility in low ambient oxygen. Src inhibition by Dasatinib abrogates this phenotype. Molecular discovery and validation studies evaluate 46 molecules related to motility or the src pathway in U251 cells. Demanding that the molecular changes induced by low ambient oxygen are reversed by Dasatinib in U251 cells, identifies neural Wiskott-Aldrich syndrome protein (NWASP), Focal adhesion Kinase (FAK), [Formula: see text]-Catenin, and Cofilin. However, only Src-mediated NWASP phosphorylation distinguishes the four cell lines that exhibit enhanced motility in low ambient oxygen. Downregulating c-Src or NWASP by RNA interference abrogates the low-oxygen-induced enhancement in motility by in vitro assays and in organotypic brain slice cultures. The findings support the idea that c-Src and NWASP play key roles in mediating the molecular pathogenesis of low oxygen-induced accelerated brain invasion by gliomas.

  3. Increased leucine-rich repeats and immunoglobulin- like domains 1 expression enhances chemosensitivity in glioma

    Institute of Scientific and Technical Information of China (English)

    Baohui Liu; Shenqi Zhang; Dong Ruan; Xiaonan Zhu; Zhentao Guo; Huimin Dong; Mingmin Yan; Qianxue Chen; Daofeng Tian; Liquan Wu; Junmin Wang; Qiang Cai; Heng Shen; Baowei Ji; Long Wang

    2011-01-01

    Leucine-rich repeats and immunoglobulin-like domains 1 (LRIG1) is an anti-oncogene.LRIG1 is correlated with Bcl-2 in ependymomas.Decreased Bcl-2 and manganese superoxide dismutase expression can improve the chemosensitivity of glioma.In the present study, a tissue microarray of human brain astrocytomas was constructed.To investigate the relationship of LRIG1 with Bcl-2 and manganese superoxide dismutase, LRIG1, Bcl-2 and manganese superoxide dismutase expression in our tissue microarray was determined using immunohistochemistry.In addition, we constructed the LRIG1-U251 cell line, and its responses to doxorubicin and temozolomide were detected using the MTT assay.Results showed that LRIG1 expression was significantly negatively correlated with Bcl-2 and manganese superoxide dismutase expression in glioma.Also, proliferation of LRIG1-U251 cells exposed to doxorubicin or temozolomide was significantly inhibited, i.e.in the LRIG1-U251 cell line, the chemosensitivity to doxorubicin and temozolomide was increased.This indicates that increased LRIG1 expression produces a chemosensitivity in glioma.

  4. Predictive effect of γH2AX expression on the radiosensitivity of glioma

    Directory of Open Access Journals (Sweden)

    Jun-wei WANG

    2014-03-01

    Full Text Available Objective To observe the expression changes of γH2AX in high-grade glioma cell lines (U87, U251 and LN229 and to investigate the relationship between the expression of γ H2AX and the radiosensitivity of high-grade glioma cells in vitro.  Methods The radiosensitivity of glioma U251, U87 and LN229 cell lines were measured by clone forming assay. Afte X-ray irradiation of different doses (0, 2, 4, 6, 8 and 10 Gy, the clone forming rates of 3 cell lines were measured, and cell survival curves were drawn. The DNA double-strand break (DSB damage of 3 cell lines were determined by Western blotting assay. Results For glioma U251, U87 and LN229 cell lines, the survival fraction and clone forming rate were gradually decreased with the increase of Χ-ray radiation dose, and the radiotherapy sensitization enhancement ratio (SER of U87 cells was slightly higher compared with LN229, U251 cells (P = 0.000, for all. In the Western blotting assay, the kinetics of the expression of γH2AX protein after irradiation was featured by increase and decay. The γH2AX expression of U87, LN229 and U251 cells after irradiation reached the peak value at 2 h, 1 h and 1 h respectively (P = 0.000, 0.000, 0.015. There was positive correlation between SER and γH2AX attenuation speed (r = 0.733, P = 0.025, as well as between SER and degree of increasing (r = 0.672, P = 0.047.  Conclusions The phosphorylated histone γH2AX is expected to become a powerful tool to monitor DNA DSB and to predict the radiosensitivity in high-grade glioma nradiotherapy. doi: 10.3969/j.issn.1672-6731.2014.03.015

  5. Effects of 1-bromopropane, a substitute for chlorofluorocarbons, on BDNF expression.

    Science.gov (United States)

    Yoshida, Yasuhiro; Nakano, Yoshiteru; Ueno, Susumu; Liu, Jiqin; Fueta, Yukiko; Ishidao, Toru; Kunugita, Naoki; Yanagihara, Nobuyuki; Sugiura, Tsutomu; Hori, Hajime; Yamashita, Uki

    2009-04-01

    1-Bromopropane (1-BP) has been widely used as an alternative to ozone-depleting chlorofluorocarbons in various industries. Although the neurotoxicity of 1-BP has been recently reported, there is little information about the effect of 1-BP on the cells in brain by experimental approach. Here we studied the effect of 1-BP on brain-derived neurotrophic factor (BDNF) expression in astrocytes in vitro. The BDNF mRNA level was remarkably decreased by 1-BP in a human astrocytoma cell line, U251, and in mouse primary astrocytes. The DNA-binding and specific reporter activity of cAMP response element-binding transcription factor (CREB), which is one of the key molecules regulating BDNF expression, were reduced by 1-BP in U251 and/or mouse primary astrocytes. Additionally, protein kinase A (PKA) activity was suppressed by 1-BP in U251. These results suggest that BDNF expression was affected by 1-BP through at least PKA.

  6. Stem Cells

    Science.gov (United States)

    Stem cells are cells with the potential to develop into many different types of cells in the body. ... the body. There are two main types of stem cells: embryonic stem cells and adult stem cells. Stem ...

  7. Extraction and morphology observation of exosome from glioma cell%胶质瘤源性exosome的提取及形态学观察

    Institute of Scientific and Technical Information of China (English)

    李超; 于金录; 杨偲; 黄海燕

    2010-01-01

    目的 证实体内和体外培养的胶质瘤细胞是否均可分泌exosome,为测定其蛋白质组成提供实验基础,为进一步利用exosome对胶质瘤进行免疫治疗提供理论依据.方法 收集U251胶质瘤培养上清液和Ⅲ级星形胶质瘤囊液,利用差速离心法提取exosome,并用液相载网法在电镜下观察胶质瘤源性exosome的形态.结果 U251胶质瘤和Ⅲ级星形胶质瘤细胞均可以产生exosome,其平均直径约100 nm.结论 证实了胶质瘤细胞像其他多数细胞一样,体内和体外培养均可分泌exosome.

  8. 长链非编码RNA HOTAIR促进胶质瘤细胞侵袭%Long non-coding RNA HOTAIR promotes invasion of glioma cells

    Institute of Scientific and Technical Information of China (English)

    魏文金; 李文涛; 胡奇; 韩东风; 张雅旋; 张军霞; 吴学潮; 尤永平

    2015-01-01

    目的 探讨长链非编码RNAHOT AIR对人脑胶质瘤细胞侵袭的促进作用.方法 采用HOTAIR-siRNA寡聚核苷酸转染胶质瘤U87和U251细胞系,通过实时荧光定量PCR技术检测HOTAIR在胶质瘤细胞中的表达水平.利用Westem blot验证上皮间质化相关通路蛋白(Snail、Stat3和-catenin)、标记蛋白(E-cadherin、CDH13和Vimentin)和侵袭迁移相关基质金属蛋白酶(MMP2、MMP9)的表达变化.采用Transwell实验,观察敲低HOTAIR后其对胶质瘤细胞侵袭的影响.结果 下调HOTAIR表达后,U87和U251细胞的上皮间质化相关信号通路蛋白降低,E-cadherin和CDH13升高,Vimentin降低,MMP2和MMP9表达下降,细胞侵袭能力减弱(P<0.01).结论 HOTAIR通过诱导上皮间质化促进了胶质细胞侵袭能力.

  9. Dendritic Cell

    OpenAIRE

    Sevda Söker

    2005-01-01

    Dendritic cells, a member of family of antigen presenting cells, are most effective cells in the primary immune response. Dendritic cells originated from dendron, in mean of tree in the Greek, because of their long and elaborate cytoplasmic branching processes. Dendritic cells constitute approximately 0.1 to 1 percent of the blood’s mononuclear cell. Dendritic cells are widely distributed, and specialized for antigen capture and T cell stimulation. In this article, structures and functions of...

  10. Role of GalNAc4S-6ST in astrocytic tumor progression.

    Directory of Open Access Journals (Sweden)

    Tatsuya Kobayashi

    Full Text Available N-Acetylgalactosamine 4-sulfate 6-O-sulfotransferase (GalNAc4S-6ST is the sulfotransferase responsible for biosynthesis of highly sulfated chondroitin sulfate CS-E. Although involvements of CS-E in neuronal cell functions have been extensively analyzed, the role of GalNAc4S-6ST in astrocytic tumor progression remains unknown. Here, we reveal that GalNAc4S-6ST transcripts were detected in astrocytic tumors derived from all 30 patients examined using quantitative reverse transcription-PCR analysis. Patients with high GalNAc4S-6ST mRNA expression had significantly worse outcome compared with patients with low expression, and multivariate survival analysis disclosed that GalNAc4S-6ST is an independent poor prognostic factor for astrocytic tumors. We then tested whether CS-E enhanced haptotaxic migration of glioblastoma U251-MG cells that endogenously express both the CS-E's scaffold tyrosine phosphatase ζ (PTPζ and GalNAc4S-6ST, in the presence of CS-E's preferred ligands, pleiotrophin (PTN or midkine (MK, using a modified Boyden chamber method. Haptotaxic stimulation of cell migration by PTN was most robust on control siRNA-transfected U251-MG cells, while that enhancing effect was cancelled following transduction of GalNAc4S-6ST siRNA. Similar results were obtained using MK, suggesting that both PTN and MK enhance migration of U251-MG cells by binding to CS-E. We also found that PTPζ as well as PTN and MK were frequently expressed in astrocytic tumor cells. Thus, our findings indicate that GalNAc4S-6ST mRNA expressed by astrocytic tumor cells is associated with poor patient prognosis likely by enhancing CS-E-mediated tumor cell motility in the presence of PTN and/or MK.

  11. IL-13Ra2- and glioma stem cell-pulsed dendritic cells induce glioma cell death in vitro

    Institute of Scientific and Technical Information of China (English)

    Ying Wang; Ruifan Xie; Hongquan Niu; Ting Lei

    2016-01-01

    Objective Gliomas are the most common malignant tumors in the central nervous system. Despite mul-tiple therapies including surgery, chemotherapy, and radiotherapy, the prognosis of patients remains poor. Immunotherapy is an alternative method of treating glioma, and the use of dendritic cel vaccines is one of the promising treatment options. However, there is no specific tumor cel antigen that can trigger dendritic cel s (DCs). IL-13Ra2 is a specific antigen expressed in glioma cel s; in the current study, we have at-tempted to explore whether IL-13Ra2 could be the antigen that triggers DCs and to envisage its application as potential therapy for glioma. Methods The expression of IL-13Ra2 was detected in U251 glioma cel lines and primary glioma tissues using dif erent methods. DCs from human blood were isolated and pulsed with recombinant IL-13Ra2, fol-lowing which the cytotoxicity of these DCs on glioma cel s was detected and analyzed. Results About 55.9% human glioma tissue cel s expressed IL-13Ra2, while normal brain tissue cel s did not show any expression. DC vaccines loaded with IL-13Ra2, glioma cel antigen, and brain tumor stem cel (BTSC) antigen could significantly stimulate the proliferation of T lymphocytes and induce cel death in the glioma tissue. Compared to other groups, DC vaccines loaded with BTSC antigen showed the strongest ability to activate cytotoxic T lymphocytes (CTLs), while the glioma cel antigen group showed no significant dif erence. Conclusion IL-13Ra2, which is expressed in gliomas and by glioma stem cel s, as wel as IL-13Ra2 could prove to be potential antigens for DC vaccine-based immunotherapy.

  12. Galvanic Cells

    Science.gov (United States)

    Young, I. G.

    1973-01-01

    Many standard physical chemistry textbooks contain ambiguities which lead to confusion about standard electrode potentials, calculating cell voltages, and writing reactions for galvanic cells. This article shows how standard electrode potentials can be used to calculate cell voltages and deduce cell reactions. (Author/RH)

  13. Cell Biochips

    Science.gov (United States)

    Pioufle, B. Le; Picollet-D'Hahan, N.

    A cell biochip is a microsystem, equipped with electronic and microfluidic functions, designed to manipulate or analyse living cells. The first publications in this emerging area of research appeared toward the end of the 1980s. In 1989 Washizu described a biochip designed to fuse two cells by electropermeabilisation of the cytoplasmic membrane [1]. Research centers have devised a whole range of cell chip structures, for simultaneous or sequential analysis of single cells, cell groups, or cell tissues reconstituted on the chip. The cells are arranged in a square array on a parallel cell chip for parallel analysis, while they are examined and processed one by one in a microchannel in the case of a series cell chip. In contrast to these biochips for high-throughput analysis of a large number of cells, single-cell chips focus on the analysis of a single isolated cell. As in DNA microarrays, where a large number of oligonucleotides are ordered in a matrix array, parallel cell chips order living cells in a similar way. At each point of the array, the cells can be isolated, provided that the cell type allows this, e.g., blood cells, or cultivated in groups (most adhesion cells can only survive in groups). The aim is to allow massively parallel analysis or processing. Le Pioufle et al. describe a microdevice for the culture of single cells or small groups of cells in a micropit array [2]. Each pit is equipped to stimulate the cell or group of cells either electrically or fluidically. Among the applications envisaged are gene transfer, cell sorting, and screening in pharmacology. A complementary approach, combining the DNA microarray and cell biochip ideas, has been put forward by Bailey et al. [3]. Genes previously arrayed on the chip transfect the cultured cells on the substrate depending on their position in the array (see Fig. 19.1). This way of achieving differential lipofection on a chip was then taken up again by Yoshikawa et al. [4] with primary cells, more

  14. ERK and AKT signaling drive MED1 overexpression in prostate cancer in association with elevated proliferation and tumorigenicity.

    Science.gov (United States)

    Jin, Feng; Irshad, Shazia; Yu, Wei; Belakavadi, Madesh; Chekmareva, Marina; Ittmann, Michael M; Abate-Shen, Cory; Fondell, Joseph D

    2013-07-01

    MED1 is a key coactivator of the androgen receptor (AR) and other signal-activated transcription factors. Whereas MED1 is overexpressed in prostate cancer cell lines and is thought to coactivate distinct target genes involved in cell-cycle progression and castration-resistant growth, the underlying mechanisms by which MED1 becomes overexpressed and its oncogenic role in clinical prostate cancer have remained unclear. Here, we report that MED1 is overexpressed in the epithelium of clinically localized human prostate cancer patients, which correlated with elevated cellular proliferation. In a Nkx3.1:Pten mutant mouse model of prostate cancer that recapitulates the human disease, MED1 protein levels were markedly elevated in the epithelium of both invasive and castration-resistant adenocarcinoma prostate tissues. Mechanistic evidence showed that hyperactivated ERK and/or AKT signaling pathways promoted MED1 overexpression in prostate cancer cells. Notably, ectopic MED1 overexpression in prostate cancer xenografts significantly promoted tumor growth in nude mice. Furthermore, MED1 expression in prostate cancer cells promoted the expression of a number of novel genes involved in inflammation, cell proliferation, and survival. Together, these findings suggest that elevated MED1 is a critical molecular event associated with prostate oncogenesis.

  15. Pten Regulates Epithelial Cytodifferentiation during Prostate Development.

    Directory of Open Access Journals (Sweden)

    Isabel B Lokody

    Full Text Available Gene expression and functional studies have indicated that the molecular programmes involved in prostate development are also active in prostate cancer. PTEN has been implicated in human prostate cancer and is frequently mutated in this disease. Here, using the Nkx3.1:Cre mouse strain and a genetic deletion approach, we investigate the role of Pten specifically in the developing mouse prostate epithelia. In contrast to its role in other developing organs, this gene is dispensable for the initial developmental processes such as budding and branching. However, as cytodifferentiation progresses, abnormal luminal cells fill the ductal lumens together with augmented epithelial proliferation. This phenotype resembles the hyperplasia seen in postnatal Pten deletion models that develop neoplasia at later stages. Consistent with this, gene expression analysis showed a number of genes affected that are shared with Pten mutant prostate cancer models, including a decrease in androgen receptor regulated genes. In depth analysis of the phenotype of these mice during development revealed that loss of Pten leads to the precocious differentiation of epithelial cells towards a luminal cell fate. This study provides novel insight into the role of Pten in prostate development as part of the process of coordinating the differentiation and proliferation of cell types in time and space to form a functional organ.

  16. Pten Regulates Epithelial Cytodifferentiation during Prostate Development

    Science.gov (United States)

    Lokody, Isabel B.; Francis, Jeffrey C.; Gardiner, Jennifer R.; Erler, Janine T.; Swain, Amanda

    2015-01-01

    Gene expression and functional studies have indicated that the molecular programmes involved in prostate development are also active in prostate cancer. PTEN has been implicated in human prostate cancer and is frequently mutated in this disease. Here, using the Nkx3.1:Cre mouse strain and a genetic deletion approach, we investigate the role of Pten specifically in the developing mouse prostate epithelia. In contrast to its role in other developing organs, this gene is dispensable for the initial developmental processes such as budding and branching. However, as cytodifferentiation progresses, abnormal luminal cells fill the ductal lumens together with augmented epithelial proliferation. This phenotype resembles the hyperplasia seen in postnatal Pten deletion models that develop neoplasia at later stages. Consistent with this, gene expression analysis showed a number of genes affected that are shared with Pten mutant prostate cancer models, including a decrease in androgen receptor regulated genes. In depth analysis of the phenotype of these mice during development revealed that loss of Pten leads to the precocious differentiation of epithelial cells towards a luminal cell fate. This study provides novel insight into the role of Pten in prostate development as part of the process of coordinating the differentiation and proliferation of cell types in time and space to form a functional organ. PMID:26076167

  17. 蛋白酶体功能障碍对多巴胺能PC12细胞的特异性损伤%Specific Damage of Ubiquitin-Proteasome System Dysfunction to Dopaminergic PC12 Cells

    Institute of Scientific and Technical Information of China (English)

    周海燕; 戚辰; 范国华; 王刚; 张宇红; 陈生弟

    2006-01-01

    目的探讨蛋白酶体抑制剂lactacystin对多巴胺能PC12细胞的特异性损伤.方法不同浓度的lactacystin(1、5、10、15和20μmoL/L)分别处理多巴胺能PC12细胞和胶质瘤U251细胞24 h,MTT法检测细胞活力;50 μmol/L的lactacystin处理U251细胞24 h,MTT法检测细胞活力;10、20 μmol/L lactacystin处理PC12细胞,Western Blot检测细胞内多泛素化蛋白含量;单胺氧化酶B抑制剂selegiline(500μmol/L)和特异性酪氨酸羟化酶抑制剂α-MT(1 mmol/L)提前4 h预处理PC12细胞,再与10 μmol/Llactacystin共同作用24 h,MTT法检测细胞活力,Western Blot检测多泛素化蛋白含量.结果Lactacystin呈剂量依赖性损伤多巴胺能PC12细胞,其对胶质瘤U251细胞无毒性作用,而且其毒性与细胞内多泛素化蛋白生成增加相关.用以增加细胞内多巴胺含量的selegiline和用以减少细胞内多巴胺含量的α-MT都导致lactacystin毒性增强.结论蛋白酶体功能障碍特异性损伤多巴胺能细胞,而其特征性的神经递质多巴胺在其易感性中的作用复杂.

  18. Stem cells in cell transplantation.

    Science.gov (United States)

    Sanmartin, Agneta; English, Denis; Sanberg, Paul R

    2006-12-01

    This commentary documents the increased number of stem cell-related research reports recently published in the cell transplantation field in the journal Cell Transplantation. The journal covers a wide range of issues in cell-based therapy and regenerative medicine and is attracting clinical and preclinical articles from around the world. It thereby complements and extends the basic coverage of stem cell physiology reported in Stem Cells and Development. Sections in Cell Transplantation cover neuroscience, diabetes, hepatocytes, bone, muscle, cartilage, skin, vessels, and other tissues, as well as tissue engineering that employs novel methods with stem cells. Clearly, the continued use of biomedical engineering will depend heavily on stem cells, and these two journals are well positioned to provide comprehensive coverage of these developments.

  19. Engineering cell-cell signaling.

    Science.gov (United States)

    Blagovic, Katarina; Gong, Emily S; Milano, Daniel F; Natividad, Robert J; Asthagiri, Anand R

    2013-10-01

    Juxtacrine cell-cell signaling mediated by the direct interaction of adjoining mammalian cells is arguably the mode of cell communication that is most recalcitrant to engineering. Overcoming this challenge is crucial for progress in biomedical applications, such as tissue engineering, regenerative medicine, immune system engineering and therapeutic design. Here, we describe the significant advances that have been made in developing synthetic platforms (materials and devices) and synthetic cells (cell surface engineering and synthetic gene circuits) to modulate juxtacrine cell-cell signaling. In addition, significant progress has been made in elucidating design rules and strategies to modulate juxtacrine signaling on the basis of quantitative, engineering analysis of the mechanical and regulatory role of juxtacrine signals in the context of other cues and physical constraints in the microenvironment. These advances in engineering juxtacrine signaling lay a strong foundation for an integrative approach to utilize synthetic cells, advanced 'chassis' and predictive modeling to engineer the form and function of living tissues.

  20. The oncogenic roles of Notch1 in astrocytic gliomas in vitro and in vivo.

    Science.gov (United States)

    Xu, Peng; Qiu, Mingzhe; Zhang, Zhiyong; Kang, Chunsheng; Jiang, Rongcai; Jia, Zhifan; Wang, Guangxiu; Jiang, Hao; Pu, Peiyu

    2010-03-01

    Notch receptors play an essential role in cellular processes during embryonic and postnatal development, including maintenance of stem cell self-renewal, proliferation, and determination of cell fate and apoptosis. Deregulation of Notch signaling has been implicated in some genetic diseases and tumorigenesis. The function of Notch signaling in a variety of tumors can be either oncogenic or tumor-suppressive, depending on the cellular context. In this study, Notch1 overexpression was observed in the majority of 45 astrocytic gliomas with different grades and in U251MG glioma cells. Transfection of siRNA targeting Notch1 into U251 cells in vitro downregulated Notch1 expression, associated with inhibition of cell growth, arrest of cell cycle, reduction of cell invasiveness, and induction of cell apoptosis. Meanwhile, tumor growth was delayed in established subcutaneous gliomas in nude mice treated with Notch1 siRNA in vivo. These results suggest that Notch1 plays an important oncogenic role in the development and progression of astrocytic gliomas. Furthermore, knockdown of Notch1 expression by siRNA simultaneously downregulated the expression of EGFR and the important components of its downstream pathways, including PI3K, p-AKT, K-Ras, cyclin D1 and MMP9, indicating the crosstalk and interaction of Notch and EGFR signaling pathways.

  1. Construction and in vitro Study of an E1B-Defective Adenovirus

    Institute of Scientific and Technical Information of China (English)

    Xue Feng; Joshua Mallam Nock; Zhu Hua-bin; Dong Chang-yuan; Qi Yi-peng

    2004-01-01

    An E1B-defective adenovirus named r1/Ad was constructed by homologous recombination. The construction, selection and propagation of recombinant virus was done in the human embryonic kidney 293 cells (HEK293). The in vitro study demonstrated that the recombinant virus has the ability to replicate in and lyse some p53-deficient human tumor cells such as the human glioblastoma tumor cells (U251) and human bladder tumer cells (EJ) but not in the normal cells with functional p53 such as the human fibroblast cells (MRC-5). Also, based on the cytopathic effect (CPE), it was demonstrated that the U251 cells were more sensitive to the infection of r1/Ad than that of EJ cells under identical conditions. In this paper, it was found that r1/Ad could be very useful in studying the in vitro selective replication of E1B-defective adenovirus. This may help to determine the safety of using any E1B-defective adenoviruses in cancer gene therapy.

  2. Cell Motility

    CERN Document Server

    Lenz, Peter

    2008-01-01

    Cell motility is a fascinating example of cell behavior which is fundamentally important to a number of biological and pathological processes. It is based on a complex self-organized mechano-chemical machine consisting of cytoskeletal filaments and molecular motors. In general, the cytoskeleton is responsible for the movement of the entire cell and for movements within the cell. The main challenge in the field of cell motility is to develop a complete physical description on how and why cells move. For this purpose new ways of modeling the properties of biological cells have to be found. This long term goal can only be achieved if new experimental techniques are developed to extract physical information from these living systems and if theoretical models are found which bridge the gap between molecular and mesoscopic length scales. Cell Motility gives an authoritative overview of the fundamental biological facts, theoretical models, and current experimental developments in this fascinating area.

  3. An experimental study on effect of capsaicin-loaded nanoparticles on gliomas%辣椒碱载药纳米微球抗脑胶质瘤作用的实验研究

    Institute of Scientific and Technical Information of China (English)

    张岩松; 王新法; 罗正祥; 姜志峰; 赵鹏来; 李军; 丁一

    2014-01-01

    Objective To explore the physiochemical characteristics of the capsaicin-loaded nanoparticles prepared by methoxy polyethylene glycol-poly ( caprolactone ) ( mPEG-PCL ) amphilic block copolymer, and to evaluate the ability of the capsaicin-loaded nanoparticles to inhibits the human glioblastoma U251 cells growth.Methods mPEG-PCL amphilic block copolymer was synthesized using the ring-opening polymerization method, and the capsaicin-loaded nanoparticles were prepared with the solvent diffusion method.The uptake of nanoparticles in the glioma cells and its ability to inhibit cell proliferation were tested in human glioblastoma U251 cells.Results In vitro drug release assay revealed that the capsaicin-loaded nanoparticles presented slow-release characteristics.The NIR-797 isothiocyanate-loaded nanoparticles was found to cross the blood-brain barrier.In addition, the capsaicin-loaded nanoparticle showed a remarkable inhibition on the growth of U251 cells.Conclusions The capsaicin-loaded nanoparticles can provide an extremely promising approach for chemotherapy of gliomas.%目的:探讨聚己内脂-聚乙二醇二嵌段共聚物( mPEG-PCL)制备的辣椒碱纳米微球的理化性质,通过实验评价其抗胶质瘤效果。方法通过开环聚合法和溶剂分散法制备负载辣椒碱的纳米微球,应用负载荧光素纳米粒子的肿瘤细胞摄取实验以及辣椒碱纳米微球的细胞毒性实验。结果实验显示载药微球具有缓释特性,细胞可通过胞吞作用将纳米微球摄入,负载NIR-797纳米微球可以很好地透过血-脑屏障,辣椒碱纳米微球对U251细胞的生长有明显的抑制作用。结论 mPEG-PCL为载体的辣椒碱纳米微球能够有效抑制胶质瘤细胞增殖,为脑胶质瘤药物治疗提供了一条极有前途的治疗途径。

  4. Photovoltaic Cells

    Directory of Open Access Journals (Sweden)

    Karolis Kiela

    2012-04-01

    Full Text Available The article deals with an overview of photovoltaic cells that are currently manufactured and those being developed, including one or several p-n junction, organic and dye-sensitized cells using quantum dots. The paper describes the advantages and disadvantages of various photovoltaic cells, identifies the main parameters, explains the main reasons for the losses that may occur in photovoltaic cells and looks at the ways to minimize them.Article in Lithuanian

  5. Gata4 potentiates second heart field proliferation and Hedgehog signaling for cardiac septation.

    Science.gov (United States)

    Zhou, Lun; Liu, Jielin; Xiang, Menglan; Olson, Patrick; Guzzetta, Alexander; Zhang, Ke; Moskowitz, Ivan P; Xie, Linglin

    2017-02-21

    GATA4, an essential cardiogenic transcription factor, provides a model for dominant transcription factor mutations in human disease. Dominant GATA4 mutations cause congenital heart disease (CHD), specifically atrial and atrioventricular septal defects (ASDs and AVSDs). We found that second heart field (SHF)-specific Gata4 heterozygote embryos recapitulated the AVSDs observed in germline Gata4 heterozygote embryos. A proliferation defect of SHF atrial septum progenitors and hypoplasia of the dorsal mesenchymal protrusion, rather than anlage of the atrioventricular septum, were observed in this model. Knockdown of the cell-cycle repressor phosphatase and tensin homolog (Pten) restored cell-cycle progression and rescued the AVSDs. Gata4 mutants also demonstrated Hedgehog (Hh) signaling defects. Gata4 acts directly upstream of Hh components: Gata4 activated a cis-regulatory element at Gli1 in vitro and occupied the element in vivo. Remarkably, SHF-specific constitutive Hh signaling activation rescued AVSDs in Gata4 SHF-specific heterozygous knockout embryos. Pten expression was unchanged in Smoothened mutants, and Hh pathway genes were unchanged in Pten mutants, suggesting pathway independence. Thus, both the cell-cycle and Hh-signaling defects caused by dominant Gata4 mutations were required for CHD pathogenesis, suggesting a combinatorial model of disease causation by transcription factor haploinsufficiency.

  6. Construction of conditionally replicative adenovirus vector mediated by dual specific promoters%双特异性启动子调控条件复制腺病毒载体的构建

    Institute of Scientific and Technical Information of China (English)

    李玮; 谭建

    2013-01-01

    Objective To construct and identify the conditionally replicative adenovirus vectors which may induce the human sodium iodide symporter (hNIS) expression in the early region 1A (E1A) gene of the human telomerase reverse transcriptase (hTERT) and the glial fibrillary acidic protein (GFAP)promoter regions.Methods Immunoblotting assay was employed to detect the variation in GFAP and telomerase protein expression prior to and following viral infection of the cerebral stellar glioblastoma cells (U87),neuroglioma cells (U251) and human embryonic lung fibroblasts (MRC-5) cells.The hTERT and GFAP promoters and the hNIS genes were amplified by polymerase chain reaction for synthesis of adenoviral E1A genes.The recombinant plasmids containing hTERT and GFAP gene promoters were adopted for transfection into MRC-5,U251 and U87,which entailed assessment of the hTERT and GFAP promoter activity via fluorescent analysis after 24 h.This was followed by ligation with the E1A and hNIS genes and subsequent cloning into the plasmid pDC311 for construction of the recombinant plasmid pDC311-Tp-E1A-Gp-NIS that was identified by double enzyme digestion (EcoR Ⅰ and Sal Ⅰ) and gene sequencing.This recombinant plasmid was co-transfected with adenoviral genomic plasmid pBHGlox△E1-3Cre into the human embryonic kidney 293 cells forming the conditionally replicative recombinant adenovirus Ad-Tp-E1A-Gp-NIS.This Ad-Tp-E1A-Gp-NIS was employed to transfect the 293,MRC-5,U87 and U251 cells,whose conditional replicability was measured by plaque forming assay.The recombinant virus Ad-Tp-E1A-Gp-NIS and Ad-CMV-EGFP controls were used to transfect the U251,U87 and MRC-5 cells for detection of the capacity of 125I uptake by using a γ-ray counter.Results The expression of the 120 000 telomerase and 49 000 GFAP protein could be found in U87 and U251 cells,but not in MRC-5 cells.Glioma target gene expression could be induced by the GFAP and hTERT promoters,the efficiency of which was (62.10±6.26)

  7. Cytotoxic acetogenins from Annona glabra cultivated in Egypt

    Directory of Open Access Journals (Sweden)

    Ahmed Abdel-lateff

    2009-01-01

    Full Text Available Bio-assay guided fraction of the methanolic extract of Annona glabra seeds (Annonaceae, cultivated in Egypt, revealed to the isolation of three bis-tetrahydrofuran acetogenins; squamocin-C (1 , squamocin-D (2 , and annonin I (3 . Compounds 1 and 2 were obtained as stereoisomeric mixture. All isolates were assayed for their cytotoxicity twards brine shrimp and five in vitro cancer cell lines (A549, HT29, MCF 7, RPMI, and U251, and showed significant activity The structures of all compounds were determined by interpretation of their NMR and MS analyses.

  8. Engineering Cell-Cell Signaling

    OpenAIRE

    Blagovic, Katarina; Gong, Emily S.; Milano, Daniel F.; Natividad, Robert J.; Asthagiri, Anand R

    2013-01-01

    Juxtacrine cell-cell signaling mediated by the direct interaction of adjoining mammalian cells is arguably the mode of cell communication that is most recalcitrant to engineering. Overcoming this challenge is crucial for progress in biomedical applications, such as tissue engineering, regenerative medicine, immune system engineering and therapeutic design. Here, we describe the significant advances that have been made in developing synthetic platforms (materials and devices) and synthetic cel...

  9. Inhibition of MMP14 potentiates the therapeutic effect of temozolomide and radiation in gliomas.

    Science.gov (United States)

    Ulasov, Ilya; Thaci, Bart; Sarvaiya, Purvaba; Yi, Ruiyang; Guo, Donna; Auffinger, Brenda; Pytel, Peter; Zhang, Lingjiao; Kim, Chung Kwon; Borovjagin, Anton; Dey, Mahua; Han, Yu; Baryshnikov, Anatoly Y; Lesniak, Maciej S

    2013-08-01

    Metalloproteinases are membrane-bound proteins that play a role in the cellular responses to antiglioma therapy. Previously, it has been shown that treatment of glioma cells with temozolomide (TMZ) and radiation (XRT) induces the expression of metalloproteinase 14 (MMP14). To investigate the role of MMP14 in gliomagenesis, we used several chemical inhibitors which affect MMP14 expression. Of all the inhibitors tested, we found that Marimastat not only inhibits the expression of MMP14 in U87 and U251 glioma cells, but also induces cell cycle arrest. To determine the relationship between MMP14 inhibition and alteration of the cell cycle, we used an RNAi technique. Genetic knockdown of MMP14 in U87 and U251 glioma cells induced G2/M arrest and decreased proliferation. Mechanistically, we show that TMZ and XRT regulated expression of MMP14 in clinical samples and in vitro models through downregulation of microRNA374. In vivo genetic knockdown of MMP14 significantly decreased tumor growth of glioma xenografts and improved survival of glioma-bearing mice. Moreover, the combination of MMP14 silencing with TMZ and XRT significantly improved the survival of glioma-bearing mice compared to a single modality treatment group. Therefore, we show that the inhibition of MMP14 sensitizes tumor cells to TMZ and XRT and could be used as a future strategy for antiglioma therapy.

  10. New quinoxaline 1,4-di-N-oxides. Part 1: Hypoxia-selective cytotoxins and anticancer agents derived from quinoxaline 1,4-di-N-oxides.

    Science.gov (United States)

    Amin, Kamelia M; Ismail, Magda M F; Noaman, Eman; Soliman, Dalia H; Ammar, Yousry A

    2006-10-15

    Hypoxic cells which are common feature of solid tumors are resistant to both anticancer drugs and radiation therapy. Thus, the identification of drugs with the selective toxicity toward hypoxic cells is an important target in anticancer chemotherapy. Tirapazamine has been shown to be an efficient and selective cytotoxin after bioreductive activation in hypoxic cells which is thought to be due to the presence of the 1,4-di-N-oxide. A new series of quinoxaline 1,4-di-N-oxides and fused quinoxaline di-N-oxides were synthesized and evaluated for hypoxic-cytotoxic activity on EAC cell line. Compound 10a was the most potent cytotoxin IC(50) 0.9 microg/mL, potency 75 microg/mL, and was approximately 15 times more selective cytotoxin (HCR>111) than 3-aminoquinoxaline-2-carbonitrile which has been used as a standard (HCR>7.5). Compounds 4 and 3a,b were more selective than the standard. In addition, antitumor activity against Hepg2 (liver) and U251 (brain) human cell lines was evaluated, compounds 9c and 8a were the most active against Hepg2 with IC(50) values 1.9 and 2.9 microg/mL, respectively, however, all the tested compounds were nontoxic against U251 cell line.

  11. Stem Cells

    Directory of Open Access Journals (Sweden)

    Madhukar Thakur

    2015-02-01

    Full Text Available Objective: The objective of this presentation is to create awareness of stem cell applications in the ISORBE community and to foster a strategy of how the ISORBE community can disseminate information and promote the use of radiolabeled stem cells in biomedical applications. Methods: The continued excitement in Stem Cells, in many branches of basic and applied biomedical science, stems from the remarkable ability of stem cells to divide and develop into different types of cells in the body. Often called as Magic Seeds, stem cells are produced in bone marrow and circulate in blood, albeit at a relatively low concentration. These virtues together with the ability of stem cells to grow in tissue culture have paved the way for their applications to generate new and healthy tissues and to replace diseased or injured human organs. Although possibilities of stem cell applications are many, much remains yet to be understood of these remarkable magic seeds. Conclusion: This presentation shall briefly cover the origin of stem cells, the pros and cons of their growth and division, their potential application, and shall outline some examples of the contributions of radiolabeled stem cells, in this rapidly growing branch of biomedical science

  12. Targeting MT1-MMP as an ImmunoPET-Based Strategy for Imaging Gliomas.

    Directory of Open Access Journals (Sweden)

    A G de Lucas

    Full Text Available A critical challenge in the management of Glioblastoma Multiforme (GBM tumors is the accurate diagnosis and assessment of tumor progression in a noninvasive manner. We have identified Membrane-type 1 matrix metalloproteinase (MT1-MMP as an attractive biomarker for GBM imaging since this protein is actively involved in tumor growth and progression, correlates with tumor grade and is closely associated with poor prognosis in GBM patients. Here, we report the development of an immunoPET tracer for effective detection of MT1-MMP in GBM models.An anti-human MT1-MMP monoclonal antibody (mAb, LEM2/15, was conjugated to p-isothiocyanatobenzyl-desferrioxamine (DFO-NCS for 89Zr labeling. Biodistribution and PET imaging studies were performed in xenograft mice bearing human GBM cells (U251 expressing MT1-MMP and non-expressing breast carcinoma cells (MCF-7 as negative control. Two orthotopic brain GBM models, patient-derived neurospheres (TS543 and U251 cells, with different degrees of blood-brain barrier (BBB disruption were also used for PET imaging experiments.89Zr labeling of DFO-LEM2/15 was achieved with high yield (>90% and specific activity (78.5 MBq/mg. Biodistribution experiments indicated that 89Zr-DFO-LEM2/15 showed excellent potential as a radiotracer for detection of MT1-MMP positive GBM tumors. PET imaging also indicated a specific and prominent 89Zr-DFO-LEM2/15 uptake in MT1-MMP+ U251 GBM tumors compared to MT1-MMP- MCF-7 breast tumors. Results obtained in orthotopic brain GBM models revealed a high dependence of a disrupted BBB for tracer penetrance into tumors. 89Zr-DFO-LEM2/15 showed much higher accumulation in TS543 tumors with a highly disrupted BBB than in U251 orthotopic model in which the BBB permeability was only partially increased. Histological analysis confirmed the specificity of the immunoconjugate in all GBM models.A new anti MT1-MMP-mAb tracer, 89Zr-DFO-LEM2/15, was synthesized efficiently. In vivo validation showed high

  13. Types of Stem Cells

    Science.gov (United States)

    ... Stem Cell Glossary Search Toggle Nav Types of Stem Cells Stem cells are the foundation from which all ... Learn About Stem Cells > Types of Stem Cells Stem cells Stem cells are the foundation for every organ ...

  14. Fuel Cells

    DEFF Research Database (Denmark)

    Smith, Anders; Pedersen, Allan Schrøder

    2014-01-01

    Fuel cells have been the subject of intense research and development efforts for the past decades. Even so, the technology has not had its commercial breakthrough yet. This entry gives an overview of the technological challenges and status of fuel cells and discusses the most promising applications...... of the different types of fuel cells. Finally, their role in a future energy supply with a large share of fluctuating sustainable power sources, e.g., solar or wind, is surveyed....

  15. Passage of Magnetic Tat-Conjugated Fe3O4@SiO2 Nanoparticles Across In Vitro Blood-Brain Barrier

    Science.gov (United States)

    Zhao, Xueqin; Shang, Ting; Zhang, Xiaodan; Ye, Ting; Wang, Dajin; Rei, Lei

    2016-10-01

    Delivery of diagnostic or therapeutic agents across the blood-brain barrier (BBB) remains a major challenge of brain disease treatment. Magnetic nanoparticles are actively being developed as drug carriers due to magnetic targeting and subsequently reduced off-target effects. In this paper, we developed a magnetic SiO2@Fe3O4 nanoparticle-based carrier bound to cell-penetrating peptide Tat (SiO2@Fe3O4 -Tat) and studied its fates in accessing BBB. SiO2@Fe3O4-Tat nanoparticles (NPs) exhibited suitable magnetism and good biocompatibility. NPs adding to the apical chamber of in vitro BBB model were found in the U251 glioma cells co-cultured at the bottom of the Transwell, indicating that particles passed through the barrier and taken up by glioma cells. Moreover, the synergistic effects of Tat and magnetic field could promote the efficient cellular internalization and the permeability across the barrier. Besides, functionalization with Tat peptide allowed particles to locate into the nucleus of U251 cells than the non-conjugated NPs. These results suggest that SiO2@Fe3O4-Tat NPs could penetrate the BBB through the transcytosis of brain endothelial cells and magnetically mediated dragging. Therefore, SiO2@Fe3O4-Tat NPs could be exploited as a potential drug delivery system for chemotherapy and gene therapy of brain disease.

  16. MicroRNA-16 suppresses epithelial-mesenchymal transition‑related gene expression in human glioma.

    Science.gov (United States)

    Wang, Qin; Li, Xu; Zhu, Yu; Yang, Ping

    2014-12-01

    Glioma is one of the most prevalent types of brain tumor and is associated with the highest mortality rate of all CNS cancers. Epithelial‑mesenchymal transition (EMT) has been recognized as an important factor in tumor metastasis. Previously, it has been demonstrated that microRNA-16 (miR-16) has an important role in tumor metastasis in human cancer cell lines. However, the role of miR-16 in epithelial‑mesenchymal transition of human glioma cells remains unclear. In the present study, U87 and U251 glioma cell lines overexpressing miR-16 were established and it was identified that miR-16 suppressed invasion, adhesion, cell cycle, production of interleukin (IL)-6, IL-8 and transforming growth factor-β, and EMT-related gene expression, including vimentin, β-catenin and E-cadherin in miR-16 overexpressing U87 and U251 glioma cells. Furthermore, miR-16 suppressed EMT mainly through the downregulation of p-FAK and p-Akt expression, and nuclear factor-κB and Slug transcriptional activity. Therefore, miR-16 may be an important therapeutic target and predictor for glioma therapy.

  17. Stem cells.

    Science.gov (United States)

    Redi, Carlo Alberto; Monti, Manuela; Merico, Valeria; Neri, Tui; Zanoni, Mario; Zuccotti, Maurizio; Garagna, Silvia

    2007-01-01

    The application of stem cells to regenerative medicine is one of the actual hot topics in biomedicine. This research could help the cure of a number of diseases that are affecting a large share of the population. Some good results in cell replacement have already been obtained (infarcted heart, diabetes, Parkinson disease), apart from those of more traditional applications like severe burns and blood tumors. We are now facing crucial questions in stem cell biology. One of the key questions is how a cell begins to proliferate or differentiate. Genome reprogramming, both following nuclear transfer and cytoplast action, will likely highlight some of the molecular mechanisms of cell differentiation and dedifferentiation. In turn, these clues should be useful to the production of populations of reprogrammed cells that could develop into tissues or, in the future, into proper organs. We will overview what stem cells are, what roles they play in normal developmental processes and how stem cells could have the potential to treat diseases.

  18. Fuel Cells

    Science.gov (United States)

    Hawkins, M. D.

    1973-01-01

    Discusses the theories, construction, operation, types, and advantages of fuel cells developed by the American space programs. Indicates that the cell is an ideal small-scale power source characterized by its compactness, high efficiency, reliability, and freedom from polluting fumes. (CC)

  19. Stem Cells

    DEFF Research Database (Denmark)

    Sommerlund, Julie

    2004-01-01

    '. This paper is about tech-noscience, and about the proliferation of connections and interdependencies created by it.More specifically, the paper is about stem cells. Biotechnology in general has the power to capture the imagination. Within the field of biotechnology nothing seems more provocative...... and tantalizing than stem cells, in research, in medicine, or as products....

  20. Sickle cell anemia

    Science.gov (United States)

    ... Anemia - sickle cell; Hemoglobin SS disease (Hb SS); Sickle cell disease Images Red blood cells, sickle cell Red blood cells, normal Red blood ... multiple sickle cells Red blood cells, sickle cells Red blood cells, sickle and ... Heeney MM, Ware RE. Sickle cell disease. In: Orkin SH, Fisher DE, Ginsburg D, Look ...

  1. Protein Phosphatase 2A Inhibition with LB100 Enhances Radiation-Induced Mitotic Catastrophe and Tumor Growth Delay in Glioblastoma.

    Science.gov (United States)

    Gordon, Ira K; Lu, Jie; Graves, Christian A; Huntoon, Kristin; Frerich, Jason M; Hanson, Ryan H; Wang, Xiaoping; Hong, Christopher S; Ho, Winson; Feldman, Michael J; Ikejiri, Barbara; Bisht, Kheem; Chen, Xiaoyuan S; Tandle, Anita; Yang, Chunzhang; Arscott, W Tristram; Ye, Donald; Heiss, John D; Lonser, Russell R; Camphausen, Kevin; Zhuang, Zhengping

    2015-07-01

    Protein phosphatase 2A (PP2A) is a tumor suppressor whose function is lost in many cancers. An emerging, though counterintuitive, therapeutic approach is inhibition of PP2A to drive damaged cells through the cell cycle, sensitizing them to radiotherapy. We investigated the effects of PP2A inhibition on U251 glioblastoma cells following radiation treatment in vitro and in a xenograft mouse model in vivo. Radiotherapy alone augmented PP2A activity, though this was significantly attenuated with combination LB100 treatment. LB100 treatment yielded a radiation dose enhancement factor of 1.45 and increased the rate of postradiation mitotic catastrophe at 72 and 96 hours. Glioblastoma cells treated with combination LB100 and radiotherapy maintained increased γ-H2AX expression at 24 hours, diminishing cellular repair of radiation-induced DNA double-strand breaks. Combination therapy significantly enhanced tumor growth delay and mouse survival and decreased p53 expression 3.68-fold, compared with radiotherapy alone. LB100 treatment effectively inhibited PP2A activity and enhanced U251 glioblastoma radiosensitivity in vitro and in vivo. Combination treatment with LB100 and radiation significantly delayed tumor growth, prolonging survival. The mechanism of radiosensitization appears to be related to increased mitotic catastrophe, decreased capacity for repair of DNA double-strand breaks, and diminished p53 DNA-damage response pathway activity.

  2. Betulinic Acid Derivatives NVX-207 and B10 for Treatment of Glioblastoma—An in Vitro Study of Cytotoxicity and Radiosensitization

    Directory of Open Access Journals (Sweden)

    Matthias Bache

    2014-10-01

    Full Text Available Betulinic acid (BA, a pentacyclic triterpene, represents a new therapeutic substance that has potential benefits for treating glioblastoma. Recently, new strategies for producing BA derivatives with improved properties have evolved. However, few studies have examined the combination of BA or BA derivatives using radiotherapy. The effects of two BA derivatives, NVX-207 and B10, on cellular and radiobiological behavior were analyzed using glioblastoma cell lines (U251MG, U343MG and LN229. Based on IC50 values under normoxic conditions, we detected a 1.3–2.9-fold higher cytotoxicity of the BA derivatives B10 and NVX-207, respectively, compared to BA. Incubation using both BA derivatives led to decreased cell migration, cleavage of PARP and decreased protein expression levels of Survivin. Weak radiation sensitivity enhancement was observed in U251MG cells after treatment with both BA derivatives. The enhancement factors at an irradiation dose of 6 Gy after treatment with 5 µM NVX-207 and 5 µM B10 were 1.32 (p = 0.029 and 1.55 (p = 0.002, respectively. In contrast to BA, neither NVX-207 nor B10 had additional effects under hypoxic conditions. Our results suggest that the BA derivatives NVX-207 and B10 improve the effects of radiotherapy on human malignant glioma cells, particularly under normoxic conditions.

  3. Development of a blood-brain barrier model in a membrane-based microchip for characterization of drug permeability and cytotoxicity for drug screening.

    Science.gov (United States)

    Shao, Xiaojian; Gao, Dan; Chen, Yongli; Jin, Feng; Hu, Guangnan; Jiang, Yuyang; Liu, Hongxia

    2016-08-31

    Since most of the central nervous system (CNS) drug candidates show poor permeability across the blood-brain barrier (BBB), development of a reliable platform for permeability assay will greatly accelerate drug discovery. Herein, we constructed a microfluidic BBB model to mimic drug delivery into the brain to induce cytotoxicity at target cells. To reconstitute the in vivo BBB properties, human cerebral microvessel endothelial cells (hCMEC/D3) were dynamically cultured in a membrane-based microchannel. Sunitinib, a model drug, was then delivered into the microchannel and forced to permeate through the BBB model. The permeated amount was directly quantified by an electrospray ionization quadrupole time-of-flight mass spectrometer (ESI-Q-TOF MS) after on-chip SPE (μSPE) pretreatment. Moreover, the permeated drug was incubated with glioma cells (U251) cultured inside agarose gel in the downstream to investigate drug-induced cytotoxicity. The resultant permeability of sunitinib was highly correlated with literature reported value, and it only required 30 min and 5 μL of sample solution for each permeation experiment. Moreover, after 48 h of treatment, the survival rate of U251 cells cultured in 3D scaffolds was nearly 6% higher than that in 2D, which was in accordance with the previously reported results. These results demonstrate that this platform provides a valid tool for drug permeability and cytotoxicity assays which have great value for the research and development of CNS drugs.

  4. Bi-Cell Unit for Fuel Cell.

    Science.gov (United States)

    The patent concerns a bi-cell unit for a fuel cell . The bi-cell unit is comprised of two electrode packs. Each of the electrode packs includes an...invention relates in general to a bi-cell unit for a fuel cell and in particular, to a bi-cell unit for a hydrazine-air fuel cell .

  5. Cell, cell, cell: fuel cell applications moving ahead

    Energy Technology Data Exchange (ETDEWEB)

    Ross, E.

    2001-11-01

    Developments in fuel cell technology within the last decade, such as the targeting by major automakers of non-polluting fuel cells as an alternative to the internal combustion engine, are reviewed. For example, Ballard Power Systems of Vancouver is the exclusive supplier to both DaimlerCrysler and the Ford Motor Company of the fuel cell stacks that produce the power in fuel cell systems. Ballard plans the commercial launch of transit bus engines in 2002 and automotive products between 2003 and 2005. The company also sees huge opportunities for fuel cells in stationary and portable power applications. At the same time, the Calgary-based fuel cell division of Energy Ventures Inc. is developing a direct methanol fuel cell that eliminates the intermediate step of 'reforming' methanol into hydrogen that is required in the Ballard process. Energy Ventures targets small niche markets such as small utility vehicles for its direct methanol fuel cell. A completely self-contained fuel cell of this type is expected to be ready in 2002. Solid oxide fuel cells for off-grid remote power units as well as for home heat and power is yet another field of development that will be particularly attractive to operations in remote areas where reliable grid electricity is expensive and hard to obtain. A prototype 2.3 kW residential power system using natural gas was made available by Global Thermoelectric Inc in June 2001; field testing is planned for 2002, with commercial production in late 2003 or 2004. The Calgary-based Snow Leopard Resources Inc plans to use pure hydrogen sulphide obtained from sour natural gas as a hydrogen source. The prime focus of Snow Leopard is on gas plants looking for ways to increase their efficiency, obtain carbon dioxide credits and generate electricity on site. This type of fuel cell also could be of interest to companies with shut-in sour gas since these companies could use the stationary fuel cell system to generate electricity.

  6. Learn About Stem Cells

    Science.gov (United States)

    ... Patient Handbook Stem Cell Glossary Search Toggle Nav Stem Cell Basics Stem cells are the foundation from which ... original cell’s DNA, cytoplasm and cell membrane. About stem cells Stem cells are the foundation of development in ...

  7. Fuel cells

    Directory of Open Access Journals (Sweden)

    D. N. Srivastava

    1962-05-01

    Full Text Available The current state of development of fuel cells as potential power sources is reviewed. Applications in special fields with particular reference to military requirements are pointed out.

  8. Functionalized magnetic nanochains with enhanced MR imaging: A novel nanosystem for targeting and inhibition of early glioma.

    Science.gov (United States)

    Zhang, Yi; Huang, Zhongbing; Wu, Zhi; Yin, Guangfu; Wang, Lei; Gao, Fabao

    2016-04-01

    Absence of efficient targeting limits the application of magnetic nanochains (NCs) in the diagnosis of early brain cancer. Herein, dextran-coated NCs (more than 100 nm length and ∼ 10 nm cores diameter), which were modified by cyclic pentapeptide c(RGDyC) or chlorotoxin (CTX) as the targeting molecules, were fabricated via carbodiimide chemistry and thiol technique. The analysis results revealed that the obtained slender NCs exhibited good biocompatibility, superparamagnetic property, high transverse relaxivity (R2) and longer blood circulation time. The test results of human umbilical vein endothelial cells and U251 human glioma cells indicated that the conjugation of c(RGDyC) could obviously increase the cyto-internalization of c(RGDyC)-NCs, however, CTX modification could significantly enhance accumulation of CTX-NCs in U251 cells, leading to cellular apoptosis. The results of in vivo biodistribution tests and in vivo magnetic resonance (MR) imaging indicated that, although the c(RGDyC)-NCs could target early glioma to some extent and obviously enhance the contrast of MR imaging, CTX-NCs possessed higher tumor-targeting ability and good inhibition effect than the c(RGDyC)-NCs, suggesting that CTX-NCs are promising candidates for the diagnosis and therapy of early glioma.

  9. Highly expressed genes in human high grade gliomas: immunohistochemical analysis of data from the Human Protein Atlas

    Directory of Open Access Journals (Sweden)

    Michael A. Meyer

    2014-06-01

    Full Text Available Gene expression within human glioblastomas were analyzed from data on 20,083 genes entered into the on-line Human Protein Atlas. In selecting genes that are strongly expressed within normal human brain tissue, 58 genes were identified from a search of the 20,083 entries that were rated as showing 90% or greater intensity of expression within normal brain tissues. Of these 58, a subset of 48 genes was identified that not only had expression data for human glioblastomas but also for the human glioblastoma cell line U-251. Four of these 48 selected genes were found to be strongly expressed within the cytoplasm when assessed by both histologic sampling of high grade glioma patient cases as well as U-251 glioblastoma cell line immunofluoresence analysis. These four human genes are: AGBL2 (ATP/GTP binding protein-like 2, BLOC1S6 (biogenesis of lysosomal organelles complex-1, subunit 6, MAP1A (microtubule-associated protein 1A and ZSWIM5 (zinc finger, SWIM-type containing 5, also known as KIAA1511. Further research is advocated to investigate the role of ZSWIM5 and AGBL2 in glioma cell biology.

  10. Electrochemical cell

    Science.gov (United States)

    Nagy, Zoltan; Yonco, Robert M.; You, Hoydoo; Melendres, Carlos A.

    1992-01-01

    An electrochemical cell has a layer-type or sandwich configuration with a Teflon center section that houses working, reference and counter electrodes and defines a relatively narrow electrolyte cavity. The center section is surrounded on both sides with thin Teflon membranes. The membranes are pressed in place by a pair of Teflon inner frames which are in turn supported by a pair of outer metal frames. The pair of inner and outer frames are provided with corresponding, appropriately shaped slits that are in plane generally transverse to the plane of the working electrode and permit X-ray beams to enter and exit the cell through the Teflon membranes that cover the slits so that the interface between the working electrode and the electrolyte within the cell may be analyzed by transmission geometry. In one embodiment, the center section consists of two parts, one on top of the other. Alternatively, the center section of the electrochemical cell may consist of two intersliding pieces or may be made of a single piece of Teflon sheet material. The electrolyte cavity is shaped so that the electrochemical cell can be rotated 90.degree. in either direction while maintaining the working and counter electrodes submerged in the electrolyte.

  11. Fuel cells:

    DEFF Research Database (Denmark)

    Sørensen, Bent

    2013-01-01

    A brief overview of the progress in fuel cell applications and basic technology development is presented, as a backdrop for discussing readiness for penetration into the marketplace as a solution to problems of depletion, safety, climate or environmental impact from currently used fossil and nucl......A brief overview of the progress in fuel cell applications and basic technology development is presented, as a backdrop for discussing readiness for penetration into the marketplace as a solution to problems of depletion, safety, climate or environmental impact from currently used fossil...

  12. CellTracks cell analysis system for rare cell detection

    NARCIS (Netherlands)

    Kagan, Michael T.; Trainer, Michael N.; Bendele, Teresa; Rao, Chandra; Horton, Allen; Tibbe, Arjan G.; Greve, Jan; Terstappen, Leon W.M.M.

    2002-01-01

    The CellTracks system is a Compact Disk-based cell analyzer that, similar to flow cytometry, differentiates cells that are aligned while passing through focused laser beams. In CellTracks, only immuno-magnetically labeled cells are aligned and remain in position for further analysis. This feature is

  13. Sickle Cell Anemia

    Science.gov (United States)

    Sickle cell anemia is a disease in which your body produces abnormally shaped red blood cells. The cells ... red blood cells. This leads to anemia. The sickle cells also get stuck in blood vessels, blocking blood ...

  14. Sickle Cell Disease

    Science.gov (United States)

    ... sickle cell disease?Sickle cell disease, also called sickle cell anemia, is a hereditary condition (which means it runs ... disease, hemoglobin SS disease, hemoglobin synthesis, hemoglobinopathies, ... cell anemia, sickle cell crisis, vaso-occlusive crisis Family Health, ...

  15. Stem Cell Information: Glossary

    Science.gov (United States)

    ... bone, cartilage, stromal cells that support blood formation, fat, and fibrous tissue. Cell-based therapies —Treatment in which stem cells are induced to differentiate into the specific cell type required to repair damaged or destroyed cells or ...

  16. Squamous Cell Carcinoma

    Science.gov (United States)

    ... Kids’ zone Video library Find a dermatologist Squamous cell carcinoma Overview Squamous cell carcinoma: This man's skin ... a squamous cell carcinoma on his face. Squamous cell carcinoma: Overview Squamous cell carcinoma (SCC) is a ...

  17. Electrochemical Cell

    DEFF Research Database (Denmark)

    1999-01-01

    The invention relates to a rechargeable electrochemical cell comprising a negative electrode, an electrolyte and a positive electrode in which the positive electrode structure comprises a lithium cobalt manganese oxide of the composition Li¿2?Co¿y?Mn¿2-y?O¿4? where 0

  18. Potent Cells

    Science.gov (United States)

    Liu, Dennis

    2007-01-01

    It seems hard to believe that Dolly the cloned sheep was born 10 years ago, kindling furious arguments over the prospects and ethics of cloning a human. Today, the controversy over cloning is entwined, often confused, with concerns over the use of human embryonic stem cells. Most people are unclear what cloning is, and they know even less when it…

  19. Photovoltaic cell

    Science.gov (United States)

    Gordon, Roy G.; Kurtz, Sarah

    1984-11-27

    In a photovoltaic cell structure containing a visibly transparent, electrically conductive first layer of metal oxide, and a light-absorbing semiconductive photovoltaic second layer, the improvement comprising a thin layer of transition metal nitride, carbide or boride interposed between said first and second layers.

  20. Construction of pSiRNA-Shh recombinant retroviral vector and its application in malignant glioma cells in vitro%pSiRNA-Shh逆转录病毒载体的构建及对恶性脑胶质瘤细胞作用的离体实验研究

    Institute of Scientific and Technical Information of China (English)

    尹昌林; 吕胜青; 黄轶; 李光辉; 唐莉; 杨辉

    2007-01-01

    目的 建立逆转录病毒介导的人Shh基因RNA干扰体外表达体系并观察对恶性脑胶质瘤细胞的作用.方法 将人Shh基因RNA干扰双链转录DNA片段重组到逆转录病毒质粒Psilencer 5.1-H1 Retro中,构建成携带人Shh基因RNA干扰逆转录病毒载体pSiRNA-Shh,经PT67细胞包装后,产生的重组逆转录病毒感染恶性脑胶质瘤细胞株U251和CHG-5细胞,用WST-8、RT-PCR和Western Blotting分别检测对转染细胞活性、人Shh mRNA和蛋白表达的影响.结果 重组pSiRNA-Shh质粒经测序鉴定正确.重组逆转录病毒滴度可达210×104 CFU/ml,感染U251和CHG-5恶性脑胶质瘤细胞株后3 d能明显抑制细胞生长,RT-PCR和Western Blotting检测人Shh mRNA和蛋白表达水平明显低于阴性对照组和未干扰组.结论 携带人Shh基因RNA干扰双链转录DNA片段的逆转录病毒体现出明显的抑制恶性脑胶质瘤细胞生长作用,为下一步开展基因治疗恶性脑胶质瘤奠定了基础.

  1. Radiosensitization by the novel DNA intercalating agent vosaroxin

    Directory of Open Access Journals (Sweden)

    Gordon Ira K

    2012-02-01

    Full Text Available Abstract Purpose Vosaroxin is a first in class naphthyridine analog structurally related to quinolone antibacterials, that intercalates DNA and inhibits topoisomerase II. Vosaroxin is not a P-glycoprotein receptor substrate and its activity is independent of p53, thus evading common drug resistance mechanisms. To evaluate vosaroxin as a clinically applicable radiation sensitizer, we investigated its effects on tumor cell radiosensitivity in vitro and in vivo. Methods Vosaroxin's effect on post-irradiation sensitivity of U251, DU145, and MiaPaca-2 cells was assessed by clonogenic assay. Subsequent mechanistic and in vivo studies were performed with U251 cells. Cell cycle distribution and G2 checkpoint integrity was analyzed by flow cytometry. DNA damage and repair was evaluated by a high throughput gamma-H2AX assay. Apoptosis was assessed by flow cytometry. Mitotic catastrophe was assessed by microscopic evidence of fragmented nuclei by immunofluorescence. In vivo radiosensitization was measured by subcutaneous tumor growth delay. Results 50-100 nmol/L treatment with vosaroxin resulted in radiosensitization of all 3 cell lines tested with a dose enhancement factor of 1.20 to 1.51 measured at a surviving fraction of 0.1. The maximal dose enhancement was seen in U251 cells treated with 75 nmol/L vosaroxin (DEF 1.51. Vosaroxin exposure did not change cell cycle distribution prior to irradiation nor alter G2 checkpoint integrity after irradiation. No difference was seen in the apoptotic fraction regardless of drug or radiation treatment. The number of cells in mitotic catastrophe was significantly greater in irradiated cells treated with vosaroxin than cells receiving radiation only at 72 hr (p = 0.009. Vosaroxin alone did not significantly increase mitotic catastrophe over control (p = 0.53. Cells treated with vosaroxin and radiation maintained significantly higher gamma-H2AX levels than cells treated with vehicle control (p = 0.014, vosaroxin (p

  2. Myxoma virus infection promotes NK lysis of malignant gliomas in vitro and in vivo.

    Directory of Open Access Journals (Sweden)

    Henry Ogbomo

    Full Text Available Myxoma virus (MYXV is a well-established oncolytic agent against different types of tumors. MYXV is also known for its immunomodulatory properties in down-regulating major histocompatibility complex (MHC I surface expression (via the M153R gene product, a viral E3-ubiquitin ligase and suppressing T cell killing of infected target cells. MHC I down-regulation, however, favors NK cell activation. Brain tumors including gliomas are characterized by high MHC I expression with impaired NK activity. We thus hypothesized that MYXV infection of glioma cells will promote NK cell-mediated recognition and killing of gliomas. We infected human gliomas with MYXV and evaluated their susceptibility to NK cell-mediated cytotoxicity. MYXV enhanced NK cell-mediated killing of glioma cells (U87 cells, MYXV vs. Mock: 51.73% vs. 28.63%, P = .0001, t test; U251 cells, MYXV vs. Mock: 40.4% vs. 20.03%, P .0007, t test. Using MYXV M153R targeted knockout (designated vMyx-M153KO to infect gliomas, we demonstrate that M153R was responsible for reduced expression of MHC I on gliomas and enhanced NK cell-mediated antiglioma activity (U87 cells, MYXV vs. vMyx-M153KO: 51.73% vs. 25.17%, P = .0002, t test; U251 cells, MYXV vs. vMyx-M153KO: 40.4% vs. 19.27, P = .0013, t test. Consequently, NK cell-mediated lysis of established human glioma tumors in CB-17 SCID mice was accelerated with improved mouse survival (log-rank P = .0072. These results demonstrate the potential for combining MYXV with NK cells to effectively kill malignant gliomas.

  3. Myxoma virus infection promotes NK lysis of malignant gliomas in vitro and in vivo.

    Science.gov (United States)

    Ogbomo, Henry; Zemp, Franz J; Lun, Xueqing; Zhang, Jiqing; Stack, Danuta; Rahman, Masmudur M; McFadden, Grant; Mody, Christopher H; Forsyth, Peter A

    2013-01-01

    Myxoma virus (MYXV) is a well-established oncolytic agent against different types of tumors. MYXV is also known for its immunomodulatory properties in down-regulating major histocompatibility complex (MHC) I surface expression (via the M153R gene product, a viral E3-ubiquitin ligase) and suppressing T cell killing of infected target cells. MHC I down-regulation, however, favors NK cell activation. Brain tumors including gliomas are characterized by high MHC I expression with impaired NK activity. We thus hypothesized that MYXV infection of glioma cells will promote NK cell-mediated recognition and killing of gliomas. We infected human gliomas with MYXV and evaluated their susceptibility to NK cell-mediated cytotoxicity. MYXV enhanced NK cell-mediated killing of glioma cells (U87 cells, MYXV vs. Mock: 51.73% vs. 28.63%, P = .0001, t test; U251 cells, MYXV vs. Mock: 40.4% vs. 20.03%, P .0007, t test). Using MYXV M153R targeted knockout (designated vMyx-M153KO) to infect gliomas, we demonstrate that M153R was responsible for reduced expression of MHC I on gliomas and enhanced NK cell-mediated antiglioma activity (U87 cells, MYXV vs. vMyx-M153KO: 51.73% vs. 25.17%, P = .0002, t test; U251 cells, MYXV vs. vMyx-M153KO: 40.4% vs. 19.27, P = .0013, t test). Consequently, NK cell-mediated lysis of established human glioma tumors in CB-17 SCID mice was accelerated with improved mouse survival (log-rank P = .0072). These results demonstrate the potential for combining MYXV with NK cells to effectively kill malignant gliomas.

  4. Fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Enomoto, Hirofumi.

    1989-05-22

    This invention aims to maintain a long-term operation with stable cell output characteristics by uniformly supplying an electrolyte from the reserver to the matrix layer over the entire matrix layer, and further to prevent the excessive wetting of the catalyst layer by smoothly absorbing the volume change of the electrolyte, caused by the repeated stop/start-up of the fuel cell, within the reserver system. For this purpose, in this invention, an electrolyte transport layer, which connects with an electrolyte reservor formed at the electrode end, is partly formed between the electrode material and the catalyst layer; a catalyst layer, which faces the electrolyte transport layer, has through-holes, which connect to the matrix, dispersely distributed. The electrolyte-transport layer is a thin sheet of a hydrophilic fibers which are non-wovens of such fibers as carbon, silicon carbide, silicon nitride or inorganic oxides. 11 figs.

  5. Biotransformation of sclareolide by filamentous fungi: cytotoxic evaluations of the derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Cano, Arturo [Universidad Nacional Autonoma de Mexico, D.F. (Mexico). Facultad de Estudios Superiores Zaragoza; Ramirez-Apan, Maria Teresa; Delgado, Guillermo, E-mail: delgado@unam.m [Universidad Nacional Autonoma de Mexico, D.F. (Mexico)

    2011-07-01

    Sclareolide (1) was incubated with eight different species of filamentous fungi conventionally used for bio-oxidations. Compound 1 was metabolized with Aspergillus niger in medium A to yield 3-ketosclareolide (2) and 3b-hydroxysclareolide (4), while in medium B (containing major number of nutrients with respect to medium A), compounds 2, 4, 3{alpha},6{beta}-dihydroxysclareolide (16), 1-ketosclareolide (17), 3-keto-15-hydroxysclareolide (18) and 3{beta},15-dihydroxysclareolide (19) were obtained. The biotransformation products 16-19 were found to be new substances. Fermentation of 1 with Cunninghamella blackesleeana using medium A afforded 2 and 4, while using medium B yielded 2, 4, 16 and 17. Compounds 2, 4 and 17 were also obtained with Curvularia lunata. Biotransformation of 1 with Beauveria bassiana yielded 4 in satisfactory yield, with Rhizopus oligosporus and Mucor miehei afforded 2 and 4, while with R. nigricans and Fusarium moliniforme yielded 2, 4 and 16. Cytotoxic evaluation of 1 and the obtained products against selected human cancer cell lines (U251, PC-3, K562, HCT-15, MCF-7 and SKUL-1) indicated that 16 (3{alpha},6{beta}-dihydroxysclareolide) displayed moderate cytotoxic (IC{sub 50} < 100 {mu}M) against U251, PC-3, HCT-15 and MCF-7. (author)

  6. Ghost cell lesions

    Directory of Open Access Journals (Sweden)

    E Rajesh

    2015-01-01

    Full Text Available Ghost cells have been a controversy for a long time. Ghost cell is a swollen/enlarged epithelial cell with eosnophilic cytoplasm, but without a nucleus. In routine H and E staining these cells give a shadowy appearance. Hence these cells are also called as shadow cells or translucent cells. The appearance of these cells varies from lesion to lesion involving odontogenic and nonodontogenic lesions. This article review about the origin, nature and significance of ghost cells in different neoplasms.

  7. [Inflammatory dendritic cells].

    Science.gov (United States)

    Segura, Elodie; Amigorena, Sebastian

    2014-01-01

    Dendritic cells are a rare and heterogeneous population of professional antigen-presenting cells. Several murine dendritic cell subpopulations have been identified that differ in their phenotype and functional properties. In the steady state, committed dendritic cell precursors differentiate into lymphoid organ-resident dendritic cells and migratory tissue dendritic cells. During inflammation appears an additional dendritic cell subpopulation that has been termed « inflammatory dendritic cells ». Inflammatory dendritic cells differentiate in situ from monocytes recruited to the site of inflammation. Here, we discuss how mouse inflammatory dendritic cells differ from macrophages and from other dendritic cell populations. Finally, we review recent work on human inflammatory dendritic cells.

  8. Red blood cells, sickle cell (image)

    Science.gov (United States)

    Sickle cell anemia is an inherited blood disease in which the red blood cells produce abnormal pigment (hemoglobin). ... abnormal hemoglobin causes deformity of the red blood cells into crescent or sickle-shapes, as seen in this photomicrograph.

  9. Red blood cells, multiple sickle cells (image)

    Science.gov (United States)

    Sickle cell anemia is an inherited disorder in which abnormal hemoglobin (the red pigment inside red blood cells) is produced. The abnormal hemoglobin causes red blood cells to assume a sickle shape, like the ones seen in this photomicrograph.

  10. CellFinder: a cell data repository

    OpenAIRE

    Stachelscheid, H.; Seltmann, S.; Lekschas, F.; Fontaine, J.F.; Mah, N.; Neves, M.; Andrade-Navarro, M.A.; Leser, U; Kurtz, A.

    2014-01-01

    CellFinder (http://www.cellfinder.org) is a comprehensive one-stop resource for molecular data characterizing mammalian cells in different tissues and in different development stages. It is built from carefully selected data sets stemming from other curated databases and the biomedical literature. To date, CellFinder describes 3394 cell types and 50 951 cell lines. The database currently contains 3055 microscopic and anatomical images, 205 whole-genome expression profiles of 194 cell/tissue t...

  11. 胞嘧啶脱氨酶/5-氟胞嘧啶自杀基因治疗系统对恶性脑胶质瘤荷瘤裸鼠的抗肿瘤作用%Antitumor efficacy of cytosine deaminase/5-fluorocytosine suicide gene therapy system against Inalignant gliomas in nude mice

    Institute of Scientific and Technical Information of China (English)

    吕胜青; 张克斌; 刘学强; 尹昌林; 邱克军; Eric E.ZHANG; 杨辉

    2008-01-01

    Objective To explore the anfitumor efficacy of cytosine deaminase/5-fluoroeytosine (CD/5-FC) suicide gene therapy system against malignant gliomas. Methods CD gene was transferred into U251 malignant glioma cell line using Lipofeetamine20OOTM-mediated method. The U251 and U251/ CD cells were seeded into the subcutaneous flank of the nude mice. After tumors appeared,5-FC (500 rag/ kg · day) was subsequently intraperitoneally injected for 10 days. The mice were sacrificed after 8 weeks, the volume and weight of tumors were evaluated. At the same time, the pathological features were analyzed for the tumor samples. Results The CD gene was successfully transferred into the U251 ceils. The in vivo animal data showed that the volume and weight of these implanted tumors were dramatically decreased from ( 1.81± 0.77) cm3 to (0.09± 0.03 )cm3, and from ( 1.63 ± 0.80) g to (0.28±0.11 ) g, respectively. Morphological observation found cell apoptosis and tumor necrosis in the transfected group. Coudusion These results indicate that the CD/5-FC suicide gene therapy system may serve as one of the main adjuvant strategies in the treatment of malignant gliomas in the future.%目的 评判胞嘧啶脱氨酶/5-氟胞嘧啶(CD/5-FC)自杀基因治疗系统对恶性脑胶质瘤的抗肿瘤效果.方法 采用Lipofectamine2000TM脂质体介导方法将CD基因转染17251恶性胶质瘤细胞系,并接种于裸鼠前臂皮下,成瘤后腹腔注射5-FC(每13500mg/kg体重)10 d,观察荷瘤鼠肿瘤的生长情况,8周后比较转染组与对照组肿瘤的体积与重量,并进行病理形态学分析.结果 U251细胞获得CD基因的成功转染,5-FC用于不同组别荷瘤裸鼠,8周后转染组肿瘤体积(0.09±0.03)cm3和重量(0.28±0.11)g明显小于对照组(1.81±0.77)cm3和(1.63±0.80)g;形态学揭示转染组肿瘤细胞出现明显的凋亡与坏死.结论 裸鼠在体实验研究表明:CD/5-FC自杀基因治疗系统是治疗恶性脑胶质瘤行之有效的手段之一.

  12. Molluscan cells in culture: primary cell cultures and cell lines

    OpenAIRE

    2013-01-01

    In vitro cell culture systems from molluscs have significantly contributed to our basic understanding of complex physiological processes occurring within or between tissue-specific cells, yielding information unattainable using intact animal models. In vitro cultures of neuronal cells from gastropods show how simplified cell models can inform our understanding of complex networks in intact organisms. Primary cell cultures from marine and freshwater bivalve and gastropod species are used as bi...

  13. Stem Cell Basics

    Science.gov (United States)

    ... Tips Info Center Research Topics Federal Policy Glossary Stem Cell Information General Information Clinical Trials Funding Information Current ... Basics » Stem Cell Basics I. Back to top Stem Cell Basics I. Introduction: What are stem cells, and ...

  14. Basal Cell Carcinoma

    Science.gov (United States)

    ... Kids’ zone Video library Find a dermatologist Basal cell carcinoma Overview Basal cell carcinoma: This skin cancer ... that has received years of sun exposure. Basal cell carcinoma: Overview Basal cell carcinoma (BCC) is the ...

  15. Electrorefining cell evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Bronson, M.C.; Thomas, R.L. (ed.)

    1989-04-14

    Operational characteristics of the LANL electrorefining cell, a modified LANL electrorefining cell, and an advanced electrorefining cell (known as the CRAC cell) were determined. Average process yields achieved were: 75% for the LANL cell, 82% for the modified LANL cell, and 86% for the CRAC cell. All product metal from the LANL and modified LANL cells was within foundry specifications. Metal from one run in the CRAC cell exceeded foundry specifications for tantalum. The LANL and modified LANL cells were simple in design and operation, but product separation was more labor intensive than with the CRAC cell. The CRAC cell was more complicated in design but remained relatively simple in operation. A decision analysis concluded that the modified LANL cell was the preferred cell. It was recommended that the modified LANL cell be implemented by the Plutonium Recovery Project at Rocky Flats and that development of the CRAC cell continue. 8 refs., 22 figs., 12 tabs.

  16. Antiparietal cell antibody test

    Science.gov (United States)

    APCA; Anti-gastric parietal cell antibody; Atrophic gastritis - anti-gastric parietal cell antibody; Gastric ulcer - anti-gastric parietal cell antibody; Pernicious anemia - anti-gastric parietal cell antibody; ...

  17. Molluscan cells in culture: primary cell cultures and cell lines.

    Science.gov (United States)

    Yoshino, T P; Bickham, U; Bayne, C J

    2013-06-01

    In vitro cell culture systems from molluscs have significantly contributed to our basic understanding of complex physiological processes occurring within or between tissue-specific cells, yielding information unattainable using intact animal models. In vitro cultures of neuronal cells from gastropods show how simplified cell models can inform our understanding of complex networks in intact organisms. Primary cell cultures from marine and freshwater bivalve and gastropod species are used as biomonitors for environmental contaminants, as models for gene transfer technologies, and for studies of innate immunity and neoplastic disease. Despite efforts to isolate proliferative cell lines from molluscs, the snail Biomphalaria glabrata Say, 1818 embryonic (Bge) cell line is the only existing cell line originating from any molluscan species. Taking an organ systems approach, this review summarizes efforts to establish molluscan cell cultures and describes the varied applications of primary cell cultures in research. Because of the unique status of the Bge cell line, an account is presented of the establishment of this cell line, and of how these cells have contributed to our understanding of snail host-parasite interactions. Finally, we detail the difficulties commonly encountered in efforts to establish cell lines from molluscs and discuss how these difficulties might be overcome.

  18. DNA-cell conjugates

    Science.gov (United States)

    Hsiao, Shih-Chia; Francis, Matthew B.; Bertozzi, Carolyn; Mathies, Richard; Chandra, Ravi; Douglas, Erik; Twite, Amy; Toriello, Nicholas; Onoe, Hiroaki

    2016-05-03

    The present invention provides conjugates of DNA and cells by linking the DNA to a native functional group on the cell surface. The cells can be without cell walls or can have cell walls. The modified cells can be linked to a substrate surface and used in assay or bioreactors.

  19. Molecular Mechanisms of Cell-cell Recognition

    Institute of Scientific and Technical Information of China (English)

    WANG Jia-Huai

    2004-01-01

    Cell-cell recognition is the key for multicellular organisms to survive. This recognition critically depends on protein-protein interactions from opposing cell surfaces. Recent structural investigations reveal unique features of these cell surface receptors and how they interact. These interactions are specific, but usually relatively weak, with more hydrophilic forces involved in binding. The receptors appear to have specialized ways to present their key interacting elements for ligand-binding from the cell surface. Cell-cell contacts are multivalent. A large group of cell surface molecules are engaged in interactions. Characteristic weak interactions make possible for each individual molecule pair within the group to constantly associate-dissociate-reassociate, such that the cell-cell recognition becomes a dynamic process. The immunological synapse is a good example for immune receptors to be orchestrated in performing immunological function in a collective fashion.

  20. Skin Stem Cells in Skin Cell Therapy

    Directory of Open Access Journals (Sweden)

    Mollapour Sisakht

    2015-12-01

    Full Text Available Context Preclinical and clinical research has shown that stem cell therapy is a promising therapeutic option for many diseases. This article describes skin stem cells sources and their therapeutic applications. Evidence Acquisition Compared with conventional methods, cell therapy reduces the surgical burden for patients because it is simple and less time-consuming. Skin cell therapy has been developed for variety of diseases. By isolation of the skin stem cell from the niche, in vitro expansion and transplantation of cells offers a surprising healing capacity profile. Results Stem cells located in skin cells have shown interesting properties such as plasticity, transdifferentiation, and specificity. Mesenchymal cells of the dermis, hypodermis, and other sources are currently being investigated to promote regeneration. Conclusions Because skin stem cells are highly accessible from autologous sources and their immunological profile is unique, they are ideal for therapeutic approaches. Optimization of administrative routes requires more investigation own to the lack of a standard protocol.

  1. Photoelectrochemical cell

    Energy Technology Data Exchange (ETDEWEB)

    Rauh, R. David (Newton, MA); Boudreau, Robert A. (Norton, MA)

    1983-06-14

    A photoelectrochemical cell comprising a sealed container having a light-transmitting window for admitting light into the container across a light-admitting plane, an electrolyte in the container, a photoelectrode in the container having a light-absorbing surface arranged to receive light from the window and in contact with the electrolyte, the surface having a plurality of spaced portions oblique to the plane, each portion having dimensions at least an order of magnitude larger than the maximum wavelength of incident sunlight, the total surface area of the surface being larger than the area of the plane bounded by the container, and a counter electrode in the container in contact with the electrolyte.

  2. nduced pluripotent stem cells and cell therapy

    Directory of Open Access Journals (Sweden)

    Banu İskender

    2013-12-01

    Full Text Available Human embryonic stem cells are derived from the inner cell mass of a blastocyst-stage embryo. They hold a huge promise for cell therapy with their self-renewing ability and pluripotency, which is known as the potential to differentiate into all cell types originating from three embryonic germ layers. However, their unique pluripotent feature could not be utilised for therapeutic purposes due to the ethical and legal problems during derivation. Recently, it was shown that the cells from adult tissues could be reverted into embryonic state, thereby restoring their pluripotent feature. This has strenghtened the possiblity of directed differentition of the reprogrammed somatic cells into the desired cell types in vitro and their use in regenerative medicine. Although these cells were termed as induced pluripotent cells, the mechanism of pluripotency has yet to be understood. Still, induced pluripotent stem cell technology is considered to be significant by proposing novel approaches in disease modelling, drug screening and cell therapy. Besides their self-renewing ability and their potential to differentiate into all cell types in a human body, they arouse a great interest in scientific world by being far from the ethical concerns regarding their embryonic counterparts and their unique feature of being patient-specific in prospective cell therapies. In this review, induced pluripotent stem cell technology and its role in cell-based therapies from past to present will be discussed. J Clin Exp Invest 2013; 4 (4: 550-561

  3. Modeling cell-in-cell structure into its biological significance

    OpenAIRE

    He, M-f; Wang, S.; Wang, Y; Wang, X-N.

    2013-01-01

    Although cell-in-cell structure was noted 100 years ago, the molecular mechanisms of ‘entering' and the destination of cell-in-cell remain largely unclear. It takes place among the same type of cells (homotypic cell-in-cell) or different types of cells (heterotypic cell-in-cell). Cell-in-cell formation affects both effector cells and their host cells in multiple aspects, while cell-in-cell death is under more intensive investigation. Given that cell-in-cell has an important role in maintainin...

  4. Tumor cell "dead or alive": caspase and survivin regulate cell death, cell cycle and cell survival.

    Science.gov (United States)

    Suzuki, A; Shiraki, K

    2001-04-01

    Cell death and cell cycle progression are two sides of the same coin, and these two different phenomenons are regulated moderately to maintain the cellular homeostasis. Tumor is one of the disease states produced as a result of the disintegrated regulation and is characterized as cells showing an irreversible progression of cell cycle and a resistance to cell death signaling. Several investigations have been performed for the understanding of cell death or cell cycle, and cell death research has remarkably progressed in these 10 years. Caspase is a nomenclature referring to ICE/CED-3 cysteine proteinase family and plays a central role during cell death. Recently, several investigations raised some possible hypotheses that caspase is also involved in cell cycle regulation. In this issue, therefore, we review the molecular basis of cell death and cell cycle regulated by caspase in tumor, especially hepatocellular carcinoma cells.

  5. Cell culture purity issues and DFAT cells

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Shengjuan [College of Animal Science and Technology, Northwest A and F University, Yangling, Shaanxi Province 712100 (China); Department of Animal Sciences, Washington State University, Pullman, WA 99164 (United States); Bergen, Werner G. [Program in Cellular and Molecular Biosciences/Department of Animal Sciences, Auburn University, Auburn, AL 36849 (United States); Hausman, Gary J. [Animal Science Department, University of Georgia, Athens, GA 30602-2771 (United States); Zan, Linsen, E-mail: zanls@yahoo.com.cn [College of Animal Science and Technology, Northwest A and F University, Yangling, Shaanxi Province 712100 (China); Dodson, Michael V., E-mail: dodson@wsu.edu [Department of Animal Sciences, Washington State University, Pullman, WA 99164 (United States)

    2013-04-12

    Highlights: •DFAT cells are progeny cells derived from dedifferentiated mature adipocytes. •Common problems in this research is potential cell contamination of initial cultures. •The initial cell culture purity is crucial in DFAT cell research field. -- Abstract: Dedifferentiation of mature adipocytes, in vitro, has been pursued/documented for over forty years. The subsequent progeny cells are named dedifferentiated adipocyte-derived progeny cells (DFAT cells). DFAT cells are proliferative and likely to possess mutilineage potential. As a consequence, DFAT cells and their progeny/daughter cells may be useful as a potential tool for various aspects of tissue engineering and as potential vectors for the alleviation of several disease states. Publications in this area have been increasing annually, but the purity of the initial culture of mature adipocytes has seldom been documented. Consequently, it is not always clear whether DFAT cells are derived from dedifferentiated mature (lipid filled) adipocytes or from contaminating cells that reside in an impure culture.

  6. Electrochemical cell

    Energy Technology Data Exchange (ETDEWEB)

    Heuts, J.J.F.G.; Willems, J.J.G.S.A.

    1987-10-13

    An electrochemical cell is described comprising a negative electrode. The electrochemically active material of which consists of an intermetallic compound forming a hydride with hydrogen, which compound has the CaCu/sub 5/-structure and the compositional formula AB/sub m/C/sub n/, where m+n is between 4.8 and 5.4, where n is between 0.05 and 0.6, in which A consists of Misch-metal or of one or more elements selected from the group consisting of Y, Ti, Hf, Zr, Ca, Th, La and the remaining rare earth metals, in which the total atomic quantities of the elements Y, Ti, Hf and Zr may not be more than 40% of A. B consists of two or more elements selected from the group formed by Ni, Co, Cu, Fe and Mn, where the maximum atomic quantity per gram atom of A is for Ni: 3.5, for Co:3.5, for Cu:3.5, for Fe:2.0 and for Mn:1.0, and C consists of one or more elements selected from the group formed by Al, Cr and Si in the indicated atomic quantities: Al:0.05-0.6, Cr:0.05-0.5 and Si:0.05-0.5, characterized in that the electrochemically active material additionally comprises one or more metals selected from the group formed by Pd, Pt, Ir and Rh, the atomic quantity per gram atom of A being from 0.001 to 0.5.

  7. CELL RESEARCH

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    REVIEWSInducible resistance to Fas-mediated apoptosis in B cells…………………………………ROTHSTEIN Thomas L (245)Executionary pathway for apoptosis: lessons from mutant mice………………………………………WOO Minna, Razqallah Hakem, Tak W Mak (267)The SHP-2 tyrosine phosphatase: Signaling mechanisms and biological functions…………………………………QU Cheng Kui (279)REGULAR ARTICLESTemperature dependent expression of cdc2 and cyclin B1 in spermatogenic cells during spermatogenesis…………………………KONG Wei Hua, Zheng GU, Jining LU, Jiake TSO (289)Transgenic mice overexpressing γ-aminobutyric acid transporter subtype I develop obesity…………………………………MA Ying Hua, Jia Hua HU, Xiao Gang ZHOU, Ruo Wang ZENG, Zhen Tong MEI, Jian FEI, Li He GUO (303)Genetic aberration in primary hepatocellular carcinoma: correlation between p53 gene mutation and loss-of-heterozygosity on chromosome 16q21-q23 and 9p21-p23………………………………………WANG Gang, Chang Hui HUANG, Yan ZHAO, Ling CAI, Ying WANG, Shi Jin XIU, Zheng Wen JIANG, Shuang YANG, Xin Tai ZHAO, Wei HUANG, Jian Ren GU (311)Identification and genetic mapping of four novel genes that regulate leaf deve- lopment in Arabidopsis………………………………………………SUN Yue, Wei ZHANG, Feng Ling LI, Ying Li GUO, Tian Lei LIU, Hai HUANG (325)NOTICE FOR CONTRIBUTORS…………………………………(337)CONTENTS of Vol. 10, 2000…………………………………………………(338)

  8. Cell culture purity issues and DFAT cells.

    Science.gov (United States)

    Wei, Shengjuan; Bergen, Werner G; Hausman, Gary J; Zan, Linsen; Dodson, Michael V

    2013-04-12

    Dedifferentiation of mature adipocytes, in vitro, has been pursued/documented for over forty years. The subsequent progeny cells are named dedifferentiated adipocyte-derived progeny cells (DFAT cells). DFAT cells are proliferative and likely to possess mutilineage potential. As a consequence, DFAT cells and their progeny/daughter cells may be useful as a potential tool for various aspects of tissue engineering and as potential vectors for the alleviation of several disease states. Publications in this area have been increasing annually, but the purity of the initial culture of mature adipocytes has seldom been documented. Consequently, it is not always clear whether DFAT cells are derived from dedifferentiated mature (lipid filled) adipocytes or from contaminating cells that reside in an impure culture.

  9. Cell Membrane Softening in Cancer Cells

    Science.gov (United States)

    Schmidt, Sebastian; Händel, Chris; Käs, Josef

    Biomechanical properties are useful characteristics and regulators of the cell's state. Current research connects mechanical properties of the cytoskeleton to many cellular processes but does not investigate the biomechanics of the plasma membrane. We evaluated thermal fluctuations of giant plasma membrane vesicles, directly derived from the plasma membranes of primary breast and cervical cells and observed a lowered rigidity in the plasma membrane of malignant cells compared to non-malignant cells. To investigate the specific role of membrane rigidity changes, we treated two cell lines with the Acetyl-CoA carboxylase inhibitor Soraphen A. It changed the lipidome of cells and drastically increased membrane stiffness by up regulating short chained membrane lipids. These altered cells had a decreased motility in Boyden chamber assays. Our results indicate that the thermal fluctuations of the membrane, which are much smaller than the fluctuations driven by the cytoskeleton, can be modulated by the cell and have an impact on adhesion and motility.

  10. Mammary stem cells have myoepithelial cell properties.

    Science.gov (United States)

    Prater, Michael D; Petit, Valérie; Alasdair Russell, I; Giraddi, Rajshekhar R; Shehata, Mona; Menon, Suraj; Schulte, Reiner; Kalajzic, Ivo; Rath, Nicola; Olson, Michael F; Metzger, Daniel; Faraldo, Marisa M; Deugnier, Marie-Ange; Glukhova, Marina A; Stingl, John

    2014-10-01

    Contractile myoepithelial cells dominate the basal layer of the mammary epithelium and are considered to be differentiated cells. However, we observe that up to 54% of single basal cells can form colonies when seeded into adherent culture in the presence of agents that disrupt actin-myosin interactions, and on average, 65% of the single-cell-derived basal colonies can repopulate a mammary gland when transplanted in vivo. This indicates that a high proportion of basal myoepithelial cells can give rise to a mammary repopulating unit (MRU). We demonstrate that myoepithelial cells, flow-sorted using two independent myoepithelial-specific reporter strategies, have MRU capacity. Using an inducible lineage-tracing approach we follow the progeny of myoepithelial cells that express α-smooth muscle actin and show that they function as long-lived lineage-restricted stem cells in the virgin state and during pregnancy.

  11. GSPEL - Fuel Cell Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Fuel Cell Lab (FCL) Provides testing for technology readiness of fuel cell systems The FCL investigates, tests and verifies the performance of fuel-cell systems...

  12. Cell sheet engineering

    Directory of Open Access Journals (Sweden)

    Masayuki Yamato

    2004-05-01

    Full Text Available We have developed ‘cell sheet engineering’ in order to avoid the limitations of tissue reconstruction using biodegradable scaffolds or single cell suspension injection. Our concept is tissue reconstruction, not from single cells, but from cell sheets. Cell sheets are prepared using temperature-responsive culture dishes. Temperature-responsive polymers are covalently grafted onto the dishes, allowing various types of cells to adhere and proliferate at 37°C. The cells spontaneously detach when the temperature is reduced below 32°C without the need for proteolytic enzymes. The confluent cells are noninvasively harvested as single, contiguous cell sheets with intact cell-cell junctions and deposited extracellular matrix (ECM. We have used these harvested cell sheets for various tissue reconstructions, including ocular surfaces, periodontal ligaments, cardiac patches, and bladder augmentation.

  13. Lung cancer - small cell

    Science.gov (United States)

    Cancer - lung - small cell; Small cell lung cancer; SCLC ... About 15% of all lung cancer cases are SCLC. Small cell lung cancer is slightly more common in men than women. Almost all cases of SCLC are ...

  14. GSPEL - Fuel Cell Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Fuel Cell Lab (FCL)Provides testing for technology readiness of fuel cell systems The FCL investigates, tests and verifies the performance of fuel-cell systems...

  15. Fuel cells: A survey

    Science.gov (United States)

    Crowe, B. J.

    1973-01-01

    A survey of fuel cell technology and applications is presented. The operating principles, performance capabilities, and limitations of fuel cells are discussed. Diagrams of fuel cell construction and operating characteristics are provided. Photographs of typical installations are included.

  16. CellFinder: a cell data repository.

    Science.gov (United States)

    Stachelscheid, Harald; Seltmann, Stefanie; Lekschas, Fritz; Fontaine, Jean-Fred; Mah, Nancy; Neves, Mariana; Andrade-Navarro, Miguel A; Leser, Ulf; Kurtz, Andreas

    2014-01-01

    CellFinder (http://www.cellfinder.org) is a comprehensive one-stop resource for molecular data characterizing mammalian cells in different tissues and in different development stages. It is built from carefully selected data sets stemming from other curated databases and the biomedical literature. To date, CellFinder describes 3394 cell types and 50 951 cell lines. The database currently contains 3055 microscopic and anatomical images, 205 whole-genome expression profiles of 194 cell/tissue types from RNA-seq and microarrays and 553 905 protein expressions for 535 cells/tissues. Text mining of a corpus of >2000 publications followed by manual curation confirmed expression information on ∼900 proteins and genes. CellFinder's data model is capable to seamlessly represent entities from single cells to the organ level, to incorporate mappings between homologous entities in different species and to describe processes of cell development and differentiation. Its ontological backbone currently consists of 204 741 ontology terms incorporated from 10 different ontologies unified under the novel CELDA ontology. CellFinder's web portal allows searching, browsing and comparing the stored data, interactive construction of developmental trees and navigating the partonomic hierarchy of cells and tissues through a unique body browser designed for life scientists and clinicians.

  17. Snail modulates cell metabolism in MDCK cells

    Energy Technology Data Exchange (ETDEWEB)

    Haraguchi, Misako, E-mail: haraguci@m3.kufm.kagoshima-u.ac.jp [Department of Biochemistry and Molecular Biology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Indo, Hiroko P. [Department of Maxillofacial Radiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Iwasaki, Yasumasa [Health Care Center, Kochi University, Kochi 780-8520 (Japan); Iwashita, Yoichiro [Department of Maxillofacial Radiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Fukushige, Tomoko [Department of Dermatology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Majima, Hideyuki J. [Department of Maxillofacial Radiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Izumo, Kimiko; Horiuchi, Masahisa [Department of Environmental Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Kanekura, Takuro [Department of Dermatology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Furukawa, Tatsuhiko [Department of Molecular Oncology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Ozawa, Masayuki [Department of Biochemistry and Molecular Biology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan)

    2013-03-22

    Highlights: ► MDCK/snail cells were more sensitive to glucose deprivation than MDCK/neo cells. ► MDCK/snail cells had decreased oxidative phosphorylation, O{sub 2} consumption and ATP content. ► TCA cycle enzyme activity, but not expression, was lower in MDCK/snail cells. ► MDCK/snail cells showed reduced PDH activity and increased PDK1 expression. ► MDCK/snail cells showed reduced expression of GLS2 and ACLY. -- Abstract: Snail, a repressor of E-cadherin gene transcription, induces epithelial-to-mesenchymal transition and is involved in tumor progression. Snail also mediates resistance to cell death induced by serum depletion. By contrast, we observed that snail-expressing MDCK (MDCK/snail) cells undergo cell death at a higher rate than control (MDCK/neo) cells in low-glucose medium. Therefore, we investigated whether snail expression influences cell metabolism in MDCK cells. Although gylcolysis was not affected in MDCK/snail cells, they did exhibit reduced pyruvate dehydrogenase (PDH) activity, which controls pyruvate entry into the tricarboxylic acid (TCA) cycle. Indeed, the activity of multiple enzymes involved in the TCA cycle was decreased in MDCK/snail cells, including that of mitochondrial NADP{sup +}-dependent isocitrate dehydrogenase (IDH2), succinate dehydrogenase (SDH), and electron transport Complex II and Complex IV. Consequently, lower ATP content, lower oxygen consumption and increased survival under hypoxic conditions was also observed in MDCK/snail cells compared to MDCK/neo cells. In addition, the expression and promoter activity of pyruvate dehydrogenase kinase 1 (PDK1), which phosphorylates and inhibits the activity of PDH, was increased in MDCK/snail cells, while expression levels of glutaminase 2 (GLS2) and ATP-citrate lyase (ACLY), which are involved in glutaminolysis and fatty acid synthesis, were decreased in MDCK/snail cells. These results suggest that snail modulates cell metabolism by altering the expression and activity of

  18. Targeted Theranostic Approach for Glioma Using Dendrimer-Based Curcumin Nanoparticle

    Science.gov (United States)

    Gamage, NH; Jing, Li; Worsham, MJ; Ali, MM

    2016-01-01

    The delivery of anti-cancer agents to brain tumors represent a challenge because the blood-brain tumor barrier (BBTB) effectively limits the delivery of many agents. A new generation 3 (G3) dendrimer-based curcumin (Curc) conjugate was synthesized. The synthesized G3-Curc conjugate demonstrated full solubility in aqueous media. The in vitro study revealed that G3-Curc nanoparticles were internalized into glioma U-251 cells. Systemic delivery of G3-Curc conjugate led to preferentially accumulation in an orthotopic preclinical glioma model minimizing systemic toxic effect. Multicolor microscopy images of the tumor tissue showed that G3-Curc particles were internalized inside tumor cells selectively and further localized within nuclei. Enhanced bioavailability of G3-Curc conjugate was also observed with improved therapeutic efficacy against different cancers cells. PMID:27699139

  19. Cell aggregation and sedimentation.

    Science.gov (United States)

    Davis, R H

    1995-01-01

    The aggregation of cells into clumps or flocs has been exploited for decades in such applications as biological wastewater treatment, beer brewing, antibiotic fermentation, and enhanced sedimentation to aid in cell recovery or retention. More recent research has included the use of cell aggregation and sedimentation to selectively separate subpopulations of cells. Potential biotechnological applications include overcoming contamination, maintaining plasmid-bearing cells in continuous fermentors, and selectively removing nonviable hybridoma cells from perfusion cultures.

  20. Cell control report

    CERN Document Server

    2013-01-01

    Please note this is a Short Discount publication. This extensive report provides an essential overview of cells and their use as factory automation building blocks. The following issues are discussed in depth: Cell integration Cell software and standards Future technologies applied to cells Plus Cell control applications including: - rotary parts manufacturing - diesel engine component development - general cell control development at the General Electric Corporation - a vendor list.

  1. LY294002通过抑制胶质瘤的PI3K/Akt通路增强三氧化二砷毒性作用%LY294002 enhances cytotoxicity of ATO in glioma by down-regulation of the PI3 K/Akt pathway

    Institute of Scientific and Technical Information of China (English)

    李洋; 杨东波; 张俊和; 陈灵朝; 蒋传路

    2014-01-01

    目的:探讨LY294002通过抑制胶质瘤的PI3K/Akt 通路增加三氧化二砷( arsenic trioxide, ATO)毒性作用。方法分别用不同剂量的LY294002检测胶质瘤细胞的相对增殖率、侵袭能力、凋亡能力和PI3K、p-AKT的蛋白表达情况。选择适合的与ATO作用的LY294002浓度。结果与单独药物处理组相比,LY294002联合ATO治疗组肿瘤细胞增殖明显受到抑制。药物联合组诱导细胞凋亡,以及降低了U251细胞的侵袭性。与单独ATO治疗组相比,药物联合治疗组中,凋亡相关蛋白cleaved-caspase3及Bax显著增加。 LY294002使p-Akt及Bcl-2表达显著降低。结论 LY294002通过负调节PI3K/Akt通道提高了ATO对胶质瘤细胞的毒性作用。%Objective To explore the effect that LY294002 enhances cytotoxicity of arsenic troxide ( ATO) in glioma by down-regulating the PI3 K/Akt pathway .Methods U251 were treated with different concentrations of LY 294002 and detected by MTT assay , cell invasion as-say, apoptosis assays, and protein expression of PI3K and p-AKT were detected.Cells were treated with ATO and combination a suitable concentrations of LY 294002 .Results Prolifera-tion of tumor cell was obviously suppressed by arsenic trioxide with LY 294002 treatment than by either drug used alone .The combination treatment induced more apoptosis rate , while re-duced the invasive capability of U 251 cells.The apoptosis-associated proteins cleaved-caspase3 and Bax were more significantly up-regulated by the combined treatment than arsenic trioxi-deused alone .While, p-Akt and Bcl-2 which promoted the invasive capability of arsenic triox-ide, were significantly decreased by LY 294002 .Conclusion LY294002 enhances the cyto-toxicity of arsenic trioxide by down-regulation of PI3K/Akt pathway.

  2. Nanostructured Solar Cells

    Science.gov (United States)

    Chen, Guanying; Ning, Zhijun; Ågren, Hans

    2016-01-01

    We are glad to announce the Special Issue “Nanostructured Solar Cells”, published in Nanomaterials. This issue consists of eight articles, two communications, and one review paper, covering major important aspects of nanostructured solar cells of varying types. From fundamental physicochemical investigations to technological advances, and from single junction solar cells (silicon solar cell, dye sensitized solar cell, quantum dots sensitized solar cell, and small molecule organic solar cell) to tandem multi-junction solar cells, all aspects are included and discussed in this issue to advance the use of nanotechnology to improve the performance of solar cells with reduced fabrication costs.

  3. Squamous cell skin cancer

    Science.gov (United States)

    ... that reflect light more, such as water, sand, concrete, and areas that are painted white. The higher ... - skin - squamous cell; Skin cancer - squamous cell; Nonmelanoma skin cancer - squamous ...

  4. Cell mechanics: a dialogue

    Science.gov (United States)

    Tao, Jiaxiang; Li, Yizeng; Vig, Dhruv K.; Sun, Sean X.

    2017-03-01

    Under the microscope, eukaryotic animal cells can adopt a variety of different shapes and sizes. These cells also move and deform, and the physical mechanisms driving these movements and shape changes are important in fundamental cell biology, tissue mechanics, as well as disease biology. This article reviews some of the basic mechanical concepts in cells, emphasizing continuum mechanics description of cytoskeletal networks and hydrodynamic flows across the cell membrane. We discuss how cells can generate movement and shape changes by controlling mass fluxes at the cell boundary. These mass fluxes can come from polymerization/depolymerization of actin cytoskeleton, as well as osmotic and hydraulic pressure-driven flow of water across the cell membrane. By combining hydraulic pressure control with force balance conditions at the cell surface, we discuss a quantitative mechanism of cell shape and volume control. The broad consequences of this model on cell mechanosensation and tissue mechanics are outlined.

  5. Identification of imaging biomarkers for the assessment of tumour response to different treatments in a preclinical glioma model

    Energy Technology Data Exchange (ETDEWEB)

    Lo Dico, A.; Martelli, C. [University of Milan, Department of Pathophysiology and Transplantation, Milan (Italy); University of Milan, Centre of Molecular and Cellular Imaging-IMAGO, Milan (Italy); Valtorta, S.; Belloli, S. [National Researches Council (CNR), Institute of Molecular Bioimaging and Physiology (IBFM), Segrate, MI (Italy); IRCCS San Raffaele Scientific Institute, Experimental Imaging Center, Milan (Italy); Raccagni, I.; Moresco, R.M. [IRCCS San Raffaele Scientific Institute, Experimental Imaging Center, Milan (Italy); University of Milano-Bicocca, Department of Health Sciences, Monza (Italy); Diceglie, C. [University of Milan, Department of Pathophysiology and Transplantation, Milan (Italy); University of Milan, Doctorate School of Molecular Medicine, Milan (Italy); Gianelli, U.; Bosari, S. [University of Milan, Department of Pathophysiology and Transplantation, Milan (Italy); Fondazione IRCCS Ca' Granda-Ospedale Maggiore Policlinico, Division of Pathology, Milan (Italy); Vaira, V. [Fondazione IRCCS Ca' Granda-Ospedale Maggiore Policlinico, Division of Pathology, Milan (Italy); Istituto Nazionale Genetica Molecolare ' ' Romeo ed Enrica Invernizzi' ' (INGM), Milan (Italy); Politi, L.S. [IRCCS San Raffaele Scientific Institute, Neuroradiology Department and Neuroradiology Research Group, Milan (Italy); Lucignani, G. [University of Milan, Centre of Molecular and Cellular Imaging-IMAGO, Milan (Italy); University of Milan, Department of Health Sciences, Milan (Italy); San Paolo Hospital, Department of Diagnostic Services, Unit of Nuclear Medicine, Milan (Italy); Ottobrini, L. [University of Milan, Department of Pathophysiology and Transplantation, Milan (Italy); University of Milan, Centre of Molecular and Cellular Imaging-IMAGO, Milan (Italy); National Researches Council (CNR), Institute of Molecular Bioimaging and Physiology (IBFM), Segrate, MI (Italy)

    2015-03-27

    Hypoxia-inducible factor 1α (HIF-1α) activity is one of the major players in hypoxia-mediated glioma progression and resistance to therapies, and therefore the focus of this study was the evaluation of HIF-1α modulation in relation to tumour response with the purpose of identifying imaging biomarkers able to document tumour response to treatment in a murine glioma model. U251-HRE-mCherry cells expressing Luciferase under the control of a hypoxia responsive element (HRE) and mCherry under the control of a constitutive promoter were used to assess HIF-1α activity and cell survival after treatment, both in vitro and in vivo, by optical, MRI and positron emission tomography imaging. This cell model can be used to monitor HIF-1α activity after treatment with different drugs modulating transduction pathways involved in its regulation. After temozolomide (TMZ) treatment, HIF-1α activity is early reduced, preceding cell cytotoxicity. Optical imaging allowed monitoring of this process in vivo, and carbonic anhydrase IX (CAIX) expression was identified as a translatable non-invasive biomarker with potential clinical significance. A preliminary in vitro evaluation showed that reduction of HIF-1α activity after TMZ treatment was comparable to the effect of an Hsp90 inhibitor, opening the way for further elucidation of its mechanism of action. The results of this study suggest that the U251-HRE-mCherry cell model can be used for the monitoring of HIF-1α activity through luciferase and CAIX expression. These cells can become a useful tool for the assessment and improvement of new targeted tracers for potential theranostic procedures. (orig.)

  6. Inhibition of MMP14 potentiates the therapeutic effect of temozolomide and radiation in gliomas

    Science.gov (United States)

    Ulasov, Ilya; Thaci, Bart; Sarvaiya, Purvaba; Yi, Ruiyang; Guo, Donna; Auffinger, Brenda; Pytel, Peter; Zhang, Lingjiao; Kim, Chung Kwon; Borovjagin, Anton; Dey, Mahua; Han, Yu; Baryshnikov, Anatoly Y; Lesniak, Maciej S

    2013-01-01

    Abstract Metalloproteinases are membrane-bound proteins that play a role in the cellular responses to antiglioma therapy. Previously, it has been shown that treatment of glioma cells with temozolomide (TMZ) and radiation (XRT) induces the expression of metalloproteinase 14 (MMP14). To investigate the role of MMP14 in gliomagenesis, we used several chemical inhibitors which affect MMP14 expression. Of all the inhibitors tested, we found that Marimastat not only inhibits the expression of MMP14 in U87 and U251 glioma cells, but also induces cell cycle arrest. To determine the relationship between MMP14 inhibition and alteration of the cell cycle, we used an RNAi technique. Genetic knockdown of MMP14 in U87 and U251 glioma cells induced G2/M arrest and decreased proliferation. Mechanistically, we show that TMZ and XRT regulated expression of MMP14 in clinical samples and in vitro models through downregulation of microRNA374. In vivo genetic knockdown of MMP14 significantly decreased tumor growth of glioma xenografts and improved survival of glioma-bearing mice. Moreover, the combination of MMP14 silencing with TMZ and XRT significantly improved the survival of glioma-bearing mice compared to a single modality treatment group. Therefore, we show that the inhibition of MMP14 sensitizes tumor cells to TMZ and XRT and could be used as a future strategy for antiglioma therapy. Glioblastoma remains an incurable form of brain cancer. In this manuscript, we show that inhibition of MMP14 can potentiate the efficacy of current standard of care which includes chemo- and radiotherapy. PMID:24156018

  7. Potential Anti-cancer Activity of Furanodiene

    Institute of Scientific and Technical Information of China (English)

    Zhen-zhen Ba; Yan-ping Zheng; Hui Zhang; Xiu-yan Sun; Dong-hai Lin

    2009-01-01

    Objective: To study the anti-tumor activities of furanodiene (C15H20O), a primary sesquiterpene compound isolated from the essential oil of the rhizome of Curcuma wenyujin YH Chen et C. Ling(Wen Ezhu), in vitro and in vivo.Methods: In vitro MTT assay was used to further study the effects of time and dosage on anti-proliferation of furanodiene against the sensitive Hela, Hep-2,HL-60, U251 cells, based on the cytotoxic effects of furanodiene on 12 human malignant tumor cell lines with the essential oil of Wen Ezhu as control., and the half-inhibitory concentration (IC50) was observed. In vivo uterine cervix (U14) tumor cell was selected and the conventional assay method of anti-tumor activity was employed. Furanodiene liposome was administered intraperitoneally, and tumor-inhibitory rate, thymus and spleen indexes were observed.Results: The inhibitive effects on cell proliferation were shown in all of the twelve cell lines and the cytotoxic effects of furanodiene against Hela, Hep-2, HL-60, U251 cells were observed after 12 h of administration, the effect could last for at least 48 h in a dose dependent manner, and the IC50 values were 0.6, 1.7, 1.8, 7.0 μg/ml, respectively. Furanodiene was also found to show inhibitive effects on the proliferation of uterine cervix (U14) tumor induced in mice. The tumor inhibition rates were 36.09% (40 mg/kg), 41.55% (60 mg/kg), 58.29% (80 mg/kg), respectively.Conclusion: Furanodiene is one of primary anti-cancer active components in the essential oil of Wen Ezhu, and also a very effective agent against uterine cervix cancer, and has protection effect on the immune function.

  8. 5-Aza-CdR induced expression of NY-ESO-1 antigen in tumor cells%5-Aza-CdR诱导肿瘤细胞NY-ESO-1抗原的表达

    Institute of Scientific and Technical Information of China (English)

    陈裕庆; 黄丽; 汪晓军; 张文敏

    2010-01-01

    目的:探讨甲基化抑制剂5-氮杂-2'-脱氧胞苷(5-Aza-2'-deoxycytidine,5-Aza-CdR)对肿瘤细胞中NY-ESO-1抗原表达的诱导作用.方法:常规培养人胃癌细胞株SGC-7901、人肝癌细胞株H2P和MHCC97-H、人结肠癌细胞株HT-29和LoVo及人脑胶质瘤细胞株U251,RT-PCR和免疫细胞化学法检测5-Aza-CdR作用前后肿瘤细胞中NY-ESO-1 mRNA和蛋白的表达.结果:RT-PCR与免疫细胞化学检测仅见胃癌SGC-7901细胞阳性表达NY-ESO-1,其余5株肿瘤细胞不表达NY-ESO-1.NY-ESO-1阴性的肝癌细胞株H2P、结肠癌细胞株LoVo及脑胶质瘤细胞株U251经5-Aza-CdR(终浓度分别为1、5和10 μmol/L)处理6 d后,细胞形态和生长速度均无明显改变,而NY-ESO-1 mRNA和蛋白均被诱导为阳性表达,并随5-Aza-CdR浓度增加而阳性表达逐渐增强.结论:5-Aza-CdR能诱导肝癌、结肠癌、脑胶质瘤等肿瘤细胞中NY-ESO-1抗原的表达,为肿瘤免疫治疗提供了一条新思路.

  9. 胶质瘤来源exosome的鉴定及其蛋白质组成研究%Identification and research of protein composition of exosome from glioma cell

    Institute of Scientific and Technical Information of China (English)

    金铮; 于金录; 杨皊; 李超; 黄海燕

    2010-01-01

    目的 初步分析胶质瘤细胞分泌的exosome蛋白组成,探讨胶质瘤来源exosome 的潜在免疫调节功能,从而为进一步利用exosome 对胶质瘤进行免疫治疗提供理论依据.方法 采用差速离心法从U251胶质瘤细胞培养上清液和Ⅲ级星形胶质瘤囊液中分别提纯exosome,用透射电镜鉴定;利用二维电泳分离、分析exosome 内蛋白质,并用质谱技术鉴定了部分蛋白质.结果 胶质瘤细胞可以产生exosome,其平均直径约100 nm.二维电泳图显示U251细胞分泌的exosome含有270个蛋白点,与数据库相符的有66个;而来自Ⅲ级星形胶质瘤囊液的exosome含有242个蛋白点,与数据库相符的有60个;两者有130个蛋白点在等电点和表观分子量方面相同,其中包含HSP70、RNA结合蛋白、核酸外切酶、MHCI及MHCII类分子等.部分蛋白质点质谱鉴定结果为hCG、低密度脂蛋白、T细胞受体等.结论 胶质瘤细胞可分泌exosome,其一般特性与已报道的exosome一致,其蛋白组成与其他细胞来源的exosome 具有共性,体内和体外培养的胶质瘤细胞分泌的exosome的蛋白质组成具有同源性与差异性.胶质瘤细胞源的exosome具有一定的免疫调节功能,可以为胶质瘤免疫治疗提供理论基础.

  10. Mesenchymal stem cell like (MSCl) cells generated from human embryonic stem cells support pluripotent cell growth

    Energy Technology Data Exchange (ETDEWEB)

    Varga, Nora [Membrane Research Group of the Hungarian Academy of Sciences, Semmelweis University, Budapest (Hungary); Vereb, Zoltan; Rajnavoelgyi, Eva [Department of Immunology, Medical and Health Science Centre, University of Debrecen, Debrecen (Hungary); Nemet, Katalin; Uher, Ferenc; Sarkadi, Balazs [Membrane Research Group of the Hungarian Academy of Sciences, Semmelweis University, Budapest (Hungary); Apati, Agota, E-mail: apati@kkk.org.hu [Membrane Research Group of the Hungarian Academy of Sciences, Semmelweis University, Budapest (Hungary)

    2011-10-28

    Highlights: Black-Right-Pointing-Pointer MSC like cells were derived from hESC by a simple and reproducible method. Black-Right-Pointing-Pointer Differentiation and immunosuppressive features of MSCl cells were similar to bmMSC. Black-Right-Pointing-Pointer MSCl cells as feeder cells support the undifferentiated growth of hESC. -- Abstract: Mesenchymal stem cell like (MSCl) cells were generated from human embryonic stem cells (hESC) through embryoid body formation, and isolated by adherence to plastic surface. MSCl cell lines could be propagated without changes in morphological or functional characteristics for more than 15 passages. These cells, as well as their fluorescent protein expressing stable derivatives, efficiently supported the growth of undifferentiated human embryonic stem cells as feeder cells. The MSCl cells did not express the embryonic (Oct4, Nanog, ABCG2, PODXL, or SSEA4), or hematopoietic (CD34, CD45, CD14, CD133, HLA-DR) stem cell markers, while were positive for the characteristic cell surface markers of MSCs (CD44, CD73, CD90, CD105). MSCl cells could be differentiated toward osteogenic, chondrogenic or adipogenic directions and exhibited significant inhibition of mitogen-activated lymphocyte proliferation, and thus presented immunosuppressive features. We suggest that cultured MSCl cells can properly model human MSCs and be applied as efficient feeders in hESC cultures.

  11. T-Cell Lymphoma

    Science.gov (United States)

    Getting the Facts T-Cell Lymphoma Overview Lymphoma is the most common blood cancer. The two main forms of lymphoma are Hodgkin lymphoma ... develop into lymphomas: B-lymphocytes (B-cells) and T-lymphocytes (T-cells). T-cell lymphomas account for ...

  12. Tracking adult stem cells

    NARCIS (Netherlands)

    Snippert, H.J.G.; Clevers, H.

    2011-01-01

    The maintenance of stem-cell-driven tissue homeostasis requires a balance between the generation and loss of cell mass. Adult stem cells have a close relationship with the surrounding tissue--known as their niche--and thus, stem-cell studies should preferably be performed in a physiological context,

  13. Insect Cell Culture

    NARCIS (Netherlands)

    Oers, van M.M.; Lynn, D.E.

    2010-01-01

    Insect cell cultures are widely used in studies on insect cell physiology, developmental biology and microbial pathology. In particular, insect cell culture is an indispensable tool for the study of insect viruses. The first continuously growing insect cell cultures were established from lepidoptera

  14. Ganglion cell like cells, diagnostic dilemma

    Directory of Open Access Journals (Sweden)

    Anand Shankar Ammanagi

    2013-01-01

    Full Text Available We report a case of cutaneous swelling found on the left anterior axillary fold of a 41-year-old man. Gross examination of specimen excised from the dermis showed a well-circumscribed nodule histologically composed of spindle cells with interspersed ganglion cell like cells. On hematoxylin and eosine (H and E staining it was diagnosed as ganglioneuroma. Ganglioneuromas are rare, benign, fully differentiated tumors that contain mature schwann cells, ganglion cells, fibrous tissue, and nerve fibers. They are commonly found along the paravertebral sympathetic ganglia and sometimes in the adrenal medulla. However primary cutaneous ganglioneuroma is an extremely rare tumor. Immunohistochemical workup revealed a fibroblastic origin and hence the case was diagnosed as fibromatosis with ganglion cell like fibroblasts. This case report suggests that the features considered diagnostic of ganglioneuromas can occur in other cutaneous lesions and, therefore, this diagnosis cannot be offered only on the basis of H and E.

  15. The positive correlation between DJ-1 and β-catenin expression shows prognostic value for patients with glioma.

    Science.gov (United States)

    Wang, Chao; Fang, Mao; Zhang, Meng; Li, Weiping; Guan, Hong; Sun, Yanhua; Xie, Siming; Zhong, Xueyun

    2013-12-01

    The relationship between DJ-1 and β-catenin, and its impact on the prognosis for glioma patients has not been fully understood. This study determined the effect of DJ-1 on β-catenin and the prognostic significance of this interaction in glioma patients. We collected tumor specimens from 88 glioma patients and determined the expression of DJ-1, β-catenin and PTEN by using immunohistochemical staining. The involvement of DJ-1 and β-catenin in glioma cell lines was evaluated by immunohistochemistry and Western blotting. High DJ-1 expression (37.5%) and high β-catenin expression (34.1%) in glioma specimens were significantly associated with high grade and poor prognosis in glioma patients. However, only high levels of DJ-1 (P = 0.014) was a strong independent prognostic factor, correlated with a reduced overall survival time. In vitro DJ-1 expression was positively correlated with the expression levels of β-catenin and p-Akt, and negatively correlated with PTEN expression in U87, U251 MG, SWO-38 and SHG44 human glioma cell lines. After the knockdown of DJ-1, Akt, p-Akt or β-catenin expression levels were not affected in the PTEN-null cell lines (U87 and U251 MG). However, in the SWO-38 cell line, which has wild-type PTEN protein, the level of PTEN increased while Akt/p-Akt and β-catenin levels were reduced. Furthermore, β-catenin staining weakened in SWO-38 cells after DJ-1 levels decreased according to immunocytochemical analysis. In conclusion, DJ-1 and β-catenin may contribute to the development and recurrence of glioma and are valuable prognostic factors for glioma patients. DJ-1 may regulate β-catenin expression via PTEN and p-Akt.

  16. Novel metal chelating molecules with anticancer activity. Striking effect of the imidazole substitution of the histidine-pyridine-histidine system.

    Science.gov (United States)

    Ali, Taha F S; Iwamaru, Kana; Ciftci, Halil Ibrahim; Koga, Ryoko; Matsumoto, Masahiro; Oba, Yasunori; Kurosaki, Hiromasa; Fujita, Mikako; Okamoto, Yoshinari; Umezawa, Kazuo; Nakao, Mitsuyoshi; Hide, Takuichiro; Makino, Keishi; Kuratsu, Jun-ichi; Abdel-Aziz, Mohamed; Abuo-Rahma, Gamal El-Din A A; Beshr, Eman A M; Otsuka, Masami

    2015-09-01

    Previously we have reported a metal chelating histidine-pyridine-histidine system possessing a trityl group on the histidine imidazole, namely HPH-2Trt, which induces apoptosis in human pancreatic adenocarcinoma AsPC-1 cells. Herein the influence of the imidazole substitution of HPH-2Trt was examined. Five related compounds, HPH-1Trt, HPH-2Bzl, HPH-1Bzl, HPH-2Me, and HPH-1Me were newly synthesized and screened for their activity against AsPC-1 and brain tumor cells U87 and U251. HPH-1Trt and HPH-2Trt were highly active among the tested HPH compounds. In vitro DNA cleavage assay showed both HPH-1Trt and HPH-2Trt completely disintegrate pUC19 DNA. The introduction of trityl group decisively potentiated the activity.

  17. Generation of iPS Cells from Granulosa Cells.

    Science.gov (United States)

    Mao, Jian; Liu, Lin

    2016-01-01

    Various types of somatic cells can be reprogrammed to induced pluripotent stem (iPS) cells. Somatic stem cells may generate iPS cells more efficiently than do differentiated cells. We show that granulosa cells exhibit characteristic of somatic stem cells and can be reprogrammed to iPS cells more efficiently or with few factors. Here, we describe generation of mouse and pig iPS cells from granulosa cells with high efficiency.

  18. B cell helper assays.

    Science.gov (United States)

    Abrignani, Sergio; Tonti, Elena; Casorati, Giulia; Dellabona, Paolo

    2009-01-01

    Activation, proliferation and differentiation of naïve B lymphocytes into memory B cells and plasma cells requires engagement of the B cell receptor (BCR) coupled to T-cell help (1, 2). T cells deliver help in cognate fashion when they are activated upon recognition of specific MHC-peptide complexes presented by B cells. T cells can also deliver help in a non-cognate or bystander fashion, when they do not find specific MHC-peptide complexes on B cells and are activated by alternative mechanisms. T-cell dependent activation of B cells can be studied in vitro by experimental models called "B cell helper assays" that are based on the co-culture of B cells with activated T cells. These assays allow to decipher the molecular bases for productive T-dependent B cell responses. We show here examples of B cell helper assays in vitro, which can be reproduced with any subset of T lymphocytes that displays the appropriate helper signals.

  19. Mast cells enhance T cell activation: Importance of mast cell-derived TNF

    Science.gov (United States)

    Nakae, Susumu; Suto, Hajime; Kakurai, Maki; Sedgwick, Jonathon D.; Tsai, Mindy; Galli, Stephen J.

    2005-05-01

    Mast cells are not only important effector cells in immediate hypersensitivity reactions and immune responses to pathogens but also can contribute to T cell-mediated disorders. However, the mechanisms by which mast cells might influence T cells in such settings are not fully understood. We find that mast cells can enhance proliferation and cytokine production in multiple T cell subsets. Mast cell-dependent enhancement of T cell activation can be promoted by FcRI-dependent mast cell activation, TNF production by both mast cells and T cells, and mast cell-T cell contact. However, at high concentrations of cells, mast cells can promote T cell activation independent of IgE or TNF. Finally, mast cells also can promote T cell activation by means of soluble factors. These findings identify multiple mechanisms by which mast cells can influence T cell proliferation and cytokine production. allergy | asthma | autoimmunity | cytokines | immune response

  20. Sertoli-Leydig cell tumor

    Science.gov (United States)

    Sertoli-stromal cell tumor; Arrhenoblastoma; Androblastoma; Ovarian cancer - Sertoli-Leydig cell tumor ... The Sertoli cells are normally located in the male reproductive glands (the testes). They feed sperm cells. The Leydig cells, also ...

  1. Single cell mechanics of keratinocyte cells.

    Science.gov (United States)

    Lulevich, Valentin; Yang, Hsin-ya; Isseroff, R Rivkah; Liu, Gang-yu

    2010-11-01

    Keratinocytes represent the major cell type of the uppermost layer of human skin, the epidermis. Using AFM-based single cell compression, the ability of individual keratinocytes to resist external pressure and global rupturing forces is investigated and compared with various cell types. Keratinocytes are found to be 6-70 times stiffer than other cell types, such as white blood, breast epithelial, fibroblast, or neuronal cells, and in contrast to other cell types they retain high mechanic strength even after the cell's death. The absence of membrane rupturing peaks in the force-deformation profiles of keratinocytes and their high stiffness during a second load cycle suggests that their unique mechanical resistance is dictated by the cytoskeleton. A simple analytical model enables the quantification of Young's modulus of keratinocyte cytoskeleton, as high as 120-340 Pa. Selective disruption of the two major cytoskeletal networks, actin filaments and microtubules, does not significantly affect keratinocyte mechanics. F-actin is found to impact cell deformation under pressure. During keratinocyte compression, the plasma membrane stretches to form peripheral blebs. Instead of blebbing, cells with depolymerized F-actin respond to pressure by detaching the plasma membrane from the cytoskeleton underneath. On the other hand, the compression force of keratinocytes expressing a mutated keratin (cell line, KEB-7) is 1.6-2.2 times less than that for the control cell line that has normal keratin networks. Therefore, we infer that the keratin intermediate filament network is responsible for the extremely high keratinocyte stiffness and resilience. This could manifest into the rugged protective nature of the human epidermis.

  2. Plant stem cell niches.

    Science.gov (United States)

    Aichinger, Ernst; Kornet, Noortje; Friedrich, Thomas; Laux, Thomas

    2012-01-01

    Multicellular organisms possess pluripotent stem cells to form new organs, replenish the daily loss of cells, or regenerate organs after injury. Stem cells are maintained in specific environments, the stem cell niches, that provide signals to block differentiation. In plants, stem cell niches are situated in the shoot, root, and vascular meristems-self-perpetuating units of organ formation. Plants' lifelong activity-which, as in the case of trees, can extend over more than a thousand years-requires that a robust regulatory network keep the balance between pluripotent stem cells and differentiating descendants. In this review, we focus on current models in plant stem cell research elaborated during the past two decades, mainly in the model plant Arabidopsis thaliana. We address the roles of mobile signals on transcriptional modules involved in balancing cell fates. In addition, we discuss shared features of and differences between the distinct stem cell niches of Arabidopsis.

  3. Lung Cancer Stem Cells

    Directory of Open Access Journals (Sweden)

    Sharon R. Pine

    2008-01-01

    Full Text Available Lung cancer remains a major cause of cancer-related lethality because of high incidence and recurrence in spite of significant advances in staging and therapies. Recent data indicates that stem cells situated throughout the airways may initiate cancer formation. These putative stem cells maintain protumorigenic characteristics including high proliferative capacity, multipotent differentiation, drug resistance and long lifespan relative to other cells. Stem cell signaling and differentiation pathways are maintained within distinct cancer types, and destabilization of this machinery may participate in maintenance of cancer stem cells. Characterization of lung cancer stem cells is an area of active research and is critical for developing novel therapies. This review summarizes the current knowledge on stem cell signaling pathways and cell markers used to identify the lung cancer stem cells.

  4. What are Stem Cells?

    Directory of Open Access Journals (Sweden)

    Ahmadshah Farhat

    2014-05-01

    Full Text Available   Stem cells are undifferentiated self regenerating multi potential cells. There are three types of stem cells categories by the ability to form after cells and correlated with the body’s development process. Totipotent: these stem cells can form an entire organism such as fertilized egg. Ploripotent: ploripotent cells are those that can form any cell in the body but cannot form an entire organism such as developing embryo’s totipotent cells become ploripotent  Multipotent: Multi potent stem cells are those that can only form specific cells in the body such as blood cells based. Based on the sources of stem cells we have three types of these cells: Autologous: Sources of the patient own cells are (Autologous either the cells from patient own body or his or her cord blood. For this type of transplant the physician now usually collects the periphery rather than morrow because the procedure is easier on like a bane morrow harvest it take place outside of an operating room, and the patient does not to be under general unsetting . Allogenic: Sources of stem cells from another donore are primarily relatives (familial allogenic or completely unrelated donors. Xenogenic: In these stem cells from different species are transplanted e .g striatal porcine fetal mesan cephalic (FVM xenotransplants for Parkinson’s disease. On sites of isolation such as embryo, umbilical cord and other body tissues stem cells are named embnyonic, cord blood, and adult stem cells. The scope of results and clinical application of stem cells are such as: Neurodegenerative conditions (MS,ALS, Parkinson’s, Stroke, Ocular disorders- Glaucoma, retinitis Pigmentosa (RP, Auto Immune Conditions (Lupus, MS,R. arthritis, Diabetes, etc, Viral Conditions (Hepatitis C and AIDS, Heart Disease, Adrenal Disorders, Injury(Nerve, Brain, etc, Anti aging (hair, skin, weight control, overall well being/preventive, Emotional disorders, Organ / Tissue Cancers, Blood cancers, Blood diseases

  5. Tracking adult stem cells.

    Science.gov (United States)

    Snippert, Hugo J; Clevers, Hans

    2011-02-01

    The maintenance of stem-cell-driven tissue homeostasis requires a balance between the generation and loss of cell mass. Adult stem cells have a close relationship with the surrounding tissue--known as their niche--and thus, stem-cell studies should preferably be performed in a physiological context, rather than outside their natural environment. The mouse is an attractive model in which to study adult mammalian stem cells, as numerous experimental systems and genetic tools are available. In this review, we describe strategies commonly used to identify and functionally characterize adult stem cells in mice and discuss their potential, limitations and interpretations, as well as how they have informed our understanding of adult stem-cell biology. An accurate interpretation of physiologically relevant stem-cell assays is crucial to identify adult stem cells and elucidate how they self-renew and give rise to differentiated progeny.

  6. Stem cells in urology.

    Science.gov (United States)

    Aboushwareb, Tamer; Atala, Anthony

    2008-11-01

    The shortage of donors for organ transplantation has stimulated research on stem cells as a potential resource for cell-based therapy in all human tissues. Stem cells have been used for regenerative medicine applications in many organ systems, including the genitourinary system. The potential applications for stem cell therapy have, however, been restricted by the ethical issues associated with embryonic stem cell research. Instead, scientists have explored other cell sources, including progenitor and stem cells derived from adult tissues and stem cells derived from the amniotic fluid and placenta. In addition, novel techniques for generating stem cells in the laboratory are being developed. These techniques include somatic cell nuclear transfer, in which the nucleus of an adult somatic cell is placed into an oocyte, and reprogramming of adult cells to induce stem-cell-like behavior. Such techniques are now being used in tissue engineering applications, and some of the most successful experiments have been in the field of urology. Techniques to regenerate bladder tissue have reached the clinic, and exciting progress is being made in other areas, such as regeneration of the kidney and urethra. Cell therapy as a treatment for incontinence and infertility might soon become a reality. Physicians should be optimistic that regenerative medicine and tissue engineering will one day provide mainstream treatment options for urologic disorders.

  7. Induction of Functional Hair-Cell-Like Cells from Mouse Cochlear Multipotent Cells

    Directory of Open Access Journals (Sweden)

    Quanwen Liu

    2016-01-01

    Full Text Available In this paper, we developed a two-step-induction method of generating functional hair cells from inner ear multipotent cells. Multipotent cells from the inner ear were established and induced initially into progenitor cells committed to the inner ear cell lineage on the poly-L-lysine substratum. Subsequently, the committed progenitor cells were cultured on the mitotically inactivated chicken utricle stromal cells and induced into hair-cell-like cells containing characteristic stereocilia bundles. The hair-cell-like cells exhibited rapid permeation of FM1-43FX. The whole-cell patch-clamp technique was used to measure the membrane currents of cells differentiated for 7 days on chicken utricle stromal cells and analyze the biophysical properties of the hair-cell-like cells by recording membrane properties of cells. The results suggested that the hair-cell-like cells derived from inner ear multipotent cells were functional following differentiation in an enabling environment.

  8. Cell shape recognition by colloidal cell imprints

    NARCIS (Netherlands)

    Borovička, Josef; Stoyanov, S.D.; Paunov, V.N.

    2015-01-01

    The results presented in this study are aimed at the theoretical estimate of the interactions between a spherical microbial cell and the colloidal cell imprints in terms of the Derjaguin, Landau, Vervey, and Overbeek (DLVO) surface forces. We adapted the Derjaguin approximation to take into accou

  9. Pluripotent Stem Cells for Schwann Cell Engineering

    NARCIS (Netherlands)

    Ma, Ming-San; Boddeke, Erik; Copray, Sjef

    2015-01-01

    Tissue engineering of Schwann cells (SCs) can serve a number of purposes, such as in vitro SC-related disease modeling, treatment of peripheral nerve diseases or peripheral nerve injury, and, potentially, treatment of CNS diseases. SCs can be generated from autologous stem cells in vitro by recapitu

  10. Are mesenchymal stromal cells immune cells?

    NARCIS (Netherlands)

    M.J. Hoogduijn (Martin)

    2015-01-01

    textabstractMesenchymal stromal cells (MSCs) are considered to be promising agents for the treatment of immunological disease. Although originally identified as precursor cells for mesenchymal lineages, in vitro studies have demonstrated that MSCs possess diverse immune regulatory capacities. Pre-cl

  11. The cell cycle as a brake for β-cell regeneration from embryonic stem cells.

    Science.gov (United States)

    El-Badawy, Ahmed; El-Badri, Nagwa

    2016-01-13

    The generation of insulin-producing β cells from stem cells in vitro provides a promising source of cells for cell transplantation therapy in diabetes. However, insulin-producing cells generated from human stem cells show deficiency in many functional characteristics compared with pancreatic β cells. Recent reports have shown molecular ties between the cell cycle and the differentiation mechanism of embryonic stem (ES) cells, assuming that cell fate decisions are controlled by the cell cycle machinery. Both β cells and ES cells possess unique cell cycle machinery yet with significant contrasts. In this review, we compare the cell cycle control mechanisms in both ES cells and β cells, and highlight the fundamental differences between pluripotent cells of embryonic origin and differentiated β cells. Through critical analysis of the differences of the cell cycle between these two cell types, we propose that the cell cycle of ES cells may act as a brake for β-cell regeneration. Based on these differences, we discuss the potential of modulating the cell cycle of ES cells for the large-scale generation of functionally mature β cells in vitro. Further understanding of the factors that modulate the ES cell cycle will lead to new approaches to enhance the production of functional mature insulin-producing cells, and yield a reliable system to generate bona fide β cells in vitro.

  12. Regulatory T cells and B cells: implication on autoimmune diseases

    OpenAIRE

    Wang, Ping; Zheng, Song Guo

    2013-01-01

    The regulatory T (Treg) cells play an important role in the maintenance of homeostasis and the prevention of autoimmune diseases. Although most studies are focusing on the role of Treg cells in T cells and T cells-mediated diseases, these cells also directly affect B cells and other non-T cells. This manuscript updates the role of Treg cells on the B cells and B cell-mediated diseases. In addition, the mechanisms whereby Treg cells suppress B cell responses have been discussed.

  13. FUEL CELL ELECTRODE MATERIALS

    Science.gov (United States)

    FUEL CELL ELECTRODE MATERIALS. RAW MATERIAL SELECTION INFLUENCES POLARIZATION BUT IS NOT A SINGLE CONTROLLING FACTOR. AVAILABLE...DATA INDICATES THAT AN INTERRELATIONSHIP OF POROSITY, AVERAGE PORE VOLUME, AND PERMEABILITY CONTRIBUTES TO ELECTRODE FUEL CELL BEHAVIOR.

  14. NIA Aging Cell Repository

    Data.gov (United States)

    Federal Laboratory Consortium — To facilitate aging research on cells in culture, the NIA provides support for the NIA Aging Cell Repository, located at the Coriell Institute for Medical Research...

  15. Cell signaling review series

    Institute of Scientific and Technical Information of China (English)

    Aiming Lin; Zhenggang Liu

    2008-01-01

    @@ Signal transduction is pivotal for many, if not all, fundamental cellular functions including proliferation, differentiation, transformation and programmed cell death. Deregulation of cell signaling may result in certain types of cancers and other human diseases.

  16. Stem Cell Transplant

    Science.gov (United States)

    ... transplant is a procedure that infuses healthy blood stem cells into your body to replace your damaged or ... A bone marrow transplant is also called a stem cell transplant. A bone marrow transplant may be necessary ...

  17. Sickle cell test

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003666.htm Sickle cell test To use the sharing features on this page, please enable JavaScript. The sickle cell test looks for the abnormal hemoglobin in the ...

  18. Sickle Cell Tests

    Science.gov (United States)

    ... AACC products and services. Advertising & Sponsorship: Policy | Opportunities Sickle Cell Tests Share this page: Was this page helpful? ... else I should know? How is it used? Sickle cell tests are used to identify the presence of ...

  19. Sickle Cell Disease Quiz

    Science.gov (United States)

    ... Websites About Us Information For... Media Policy Makers Sickle Cell Disease Quiz Language: English Español (Spanish) Recommend on ... 1. True or False: Only African Americans get sickle cell disease. A True B False 2. True or ...

  20. Sickle Cell Trait

    Science.gov (United States)

    ... Websites About Us Information For... Media Policy Makers Sickle Cell Trait Language: English Español (Spanish) Recommend on Facebook ... pass the trait on to their children. How Sickle Cell Trait is Inherited If both parents have SCT, ...

  1. Sickle cell anemia.

    OpenAIRE

    ŘÍHOVÁ, Tereza

    2013-01-01

    This thesis is about the disease called sickle cell anemia, or drepanocytosis. In this thesis is described the history of the disease, pathophysiology, laboratory features, various clinical features, diferencial diagnosis, quality of life in sickle cell anemia and therapy.

  2. Giant Cell Arteritis

    Science.gov (United States)

    Giant cell arteritis is a disorder that causes inflammation of your arteries, usually in the scalp, neck, and arms. ... arteries, which keeps blood from flowing well. Giant cell arteritis often occurs with another disorder called polymyalgia ...

  3. White Blood Cell Count

    Science.gov (United States)

    ... limited. Home Visit Global Sites Search Help? White Blood Cell Count Share this page: Was this page helpful? ... Count; Leukocyte Count; White Count Formal name: White Blood Cell Count Related tests: Complete Blood Count , Blood Smear , ...

  4. Sickle Cell Information Center

    Science.gov (United States)

    ... Nature, Wash Post, SciAm, CNN - Google Custom Search Sickle Cell Anemia News -- ScienceDaily January 18, 1970 Read articles summarizing medical research on sickle-cell anemia. NYT, Nature, Wash Post, SciAm, CNN - Google Custom ...

  5. Sickle Cell Disease

    Science.gov (United States)

    ... About Us Overview of CDC’s work. Advancements in Sickle Cell Disease New supplement from the American Journal of Preventive Medicine describes the state of sickle cell disease related care in the United States. Read Supplement ...

  6. Red blood cell production

    Science.gov (United States)

    ... to one part of the body or another. Red blood cells are an important element of blood. Their job ... is carried to and eliminated by the lungs. Red blood cells are formed in the red bone marrow of ...

  7. Cell phone explosion.

    Science.gov (United States)

    Atreya, Alok; Kanchan, Tanuj; Nepal, Samata; Pandey, Bhuwan Raj

    2016-03-01

    Cell phone explosions and resultant burn injuries are rarely reported in the scientific literature. We report a case of cell phone explosion that occurred when a young male was listening to music while the mobile was plugged in for charging.

  8. Mast cell proteoglycans.

    Science.gov (United States)

    Rönnberg, Elin; Melo, Fabio R; Pejler, Gunnar

    2012-12-01

    Mast cells are versatile effector cells of the immune system, contributing to both innate and adaptive immunity toward pathogens but also having profound detrimental activities in the context of inflammatory disease. A hallmark morphological feature of mast cells is their large content of cytoplasmic secretory granules, filled with numerous secretory compounds, including highly negatively charged heparin or chondroitin sulfate proteoglycans of serglycin type. These anionic proteoglycans provide the basis for the strong metachromatic staining properties of mast cells seen when applying various cationic dyes. Functionally, the mast cell proteoglycans have been shown to have an essential role in promoting the storage of other granule-contained compounds, including bioactive monoamines and different mast cell-specific proteases. Moreover, granule proteoglycans have been shown to regulate the enzymatic activities of mast cell proteases and to promote apoptosis. Here, the current knowledge of mast cell proteoglycans is reviewed.

  9. Diagram of Cell to Cell Communication

    Science.gov (United States)

    2002-01-01

    Diagram depicts the importance of cell-cell communication as central to the understanding of cancer growth and progression, the focus of the NASA bioreactor demonstration system (BDS-05) investigation. Microgravity studies will allow us to unravel the signaling and communication between these cells with the host and potential development of therapies for the treatment of cancer metastasis. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Credit: Emory University.

  10. STEM CELLS AND PROTEOMICS

    Institute of Scientific and Technical Information of China (English)

    ZHOU Yong-ming; GUO Tian-nan; HUANG Shi-ang

    2006-01-01

    The distinctive features of proteomics are large-scale and high throughput. The key techniques of proteomics are two-dimensional gel electrophoresis, mass spectrometry and bioinformatics. Stem cell can differentiate into all kinds of cells, tissues and organs. There are many proteins and cytokines involved in the process of differentiation. Applying proteomics techniques to the research of the complex process of stem cell differentiation is of great importance to study the mechanism and applications of stem cell differentiation.

  11. Kidney Cell Electrophoresis

    Science.gov (United States)

    Todd, P.

    1985-01-01

    Materials and procedures for microgravity electrophoresis of living human embryonic kidney cells were evaluated, ground support in the form of analytical cell electrophoresis and flow cytometry was provided and cells returned from space flight were analyzed. Preflight culture media, electrophoresis buffer, fraction collection media, temperature profiles, and urokinase assay procedures were tested prior to flight. Electrophoretic mobility distributions of aliquots of the cell population to be fractionated in flight were obtained. The protocol established and utilized is given.

  12. Fish stem cell cultures.

    Science.gov (United States)

    Hong, Ni; Li, Zhendong; Hong, Yunhan

    2011-04-13

    Stem cells have the potential for self-renewal and differentiation. First stem cell cultures were derived 30 years ago from early developing mouse embryos. These are pluripotent embryonic stem (ES) cells. Efforts towards ES cell derivation have been attempted in other mammalian and non-mammalian species. Work with stem cell culture in fish started 20 years ago. Laboratory fish species, in particular zebrafish and medaka, have been the focus of research towards stem cell cultures. Medaka is the second organism that generated ES cells and the first that gave rise to a spermatogonial stem cell line capable of test-tube sperm production. Most recently, the first haploid stem cells capable of producing whole animals have also been generated from medaka. ES-like cells have been reported also in zebrafish and several marine species. Attempts for germline transmission of ES cell cultures and gene targeting have been reported in zebrafish. Recent years have witnessed the progress in markers and procedures for ES cell characterization. These include the identification of fish homologs/paralogs of mammalian pluripotency genes and parameters for optimal chimera formation. In addition, fish germ cell cultures and transplantation have attracted considerable interest for germline transmission and surrogate production. Haploid ES cell nuclear transfer has proven in medaka the feasibility of semi-cloning as a novel assisted reproductive technology. In this special issue on "Fish Stem Cells and Nuclear Transfer", we will focus our review on medaka to illustrate the current status and perspective of fish stem cells in research and application. We will also mention semi-cloning as a new development to conventional nuclear transfer.

  13. Fish Stem Cell Cultures

    Directory of Open Access Journals (Sweden)

    Ni Hong, Zhendong Li, Yunhan Hong

    2011-01-01

    Full Text Available Stem cells have the potential for self-renewal and differentiation. First stem cell cultures were derived 30 years ago from early developing mouse embryos. These are pluripotent embryonic stem (ES cells. Efforts towards ES cell derivation have been attempted in other mammalian and non-mammalian species. Work with stem cell culture in fish started 20 years ago. Laboratory fish species, in particular zebrafish and medaka, have been the focus of research towards stem cell cultures. Medaka is the second organism that generated ES cells and the first that gave rise to a spermatogonial stem cell line capable of test-tube sperm production. Most recently, the first haploid stem cells capable of producing whole animals have also been generated from medaka. ES-like cells have been reported also in zebrafish and several marine species. Attempts for germline transmission of ES cell cultures and gene targeting have been reported in zebrafish. Recent years have witnessed the progress in markers and procedures for ES cell characterization. These include the identification of fish homologs/paralogs of mammalian pluripotency genes and parameters for optimal chimera formation. In addition, fish germ cell cultures and transplantation have attracted considerable interest for germline transmission and surrogate production. Haploid ES cell nuclear transfer has proven in medaka the feasibility of semi-cloning as a novel assisted reproductive technology. In this special issue on “Fish Stem Cells and Nuclear Transfer”, we will focus our review on medaka to illustrate the current status and perspective of fish stem cells in research and application. We will also mention semi-cloning as a new development to conventional nuclear transfer.

  14. Increased voltage photovoltaic cell

    Science.gov (United States)

    Ross, B.; Bickler, D. B.; Gallagher, B. D. (Inventor)

    1985-01-01

    A photovoltaic cell, such as a solar cell, is provided which has a higher output voltage than prior cells. The improved cell includes a substrate of doped silicon, a first layer of silicon disposed on the substrate and having opposite doping, and a second layer of silicon carbide disposed on the first layer. The silicon carbide preferably has the same type of doping as the first layer.

  15. Storage of cell lines.

    Science.gov (United States)

    Parker, Katharine A

    2011-01-01

    The successful storage of cell lines depends upon many factors, including the condition of the cells to be frozen and the experience of the operator. Attempting to freeze down unhealthy, contaminated or poorly labelled cells can have huge implications for a research laboratory. This chapter outlines the importance of good record keeping, vigilant monitoring, aseptic technique, and high-quality reagents in the successful storage and downstream propagation of cell lines.

  16. Skeletal (stromal) stem cells

    DEFF Research Database (Denmark)

    Abdallah, Basem M; Kermani, Abbas Jafari; Zaher, Walid

    2015-01-01

    Skeletal (marrow stromal) stem cells (BMSCs) are a group of multipotent cells that reside in the bone marrow stroma and can differentiate into osteoblasts, chondrocytes and adipocytes. Studying signaling pathways that regulate BMSC differentiation into osteoblastic cells is a strategy....../preadipocyte factor 1 (Dlk1/Pref-1), the Wnt co-receptor Lrp5 and intracellular kinases. This article is part of a Special Issue entitled: Stem Cells and Bone....

  17. Stem cell heterogeneity revealed

    DEFF Research Database (Denmark)

    Andersen, Marianne S; Jensen, Kim B

    2016-01-01

    The skin forms a protective, water-impermeable barrier consisting of heavily crosslinked epithelial cells. However, the specific role of stem cells in sustaining this barrier remains a contentious issue. A detailed analysis of the interfollicular epidermis now proposes a model for how a composite...... of cells with different properties are involved in its maintenance....

  18. Advanced Cell Technology, Inc.

    Science.gov (United States)

    Caldwell, William M

    2007-03-01

    Advanced Cell Technology, Inc. (OTCBB: ACTC) is a biotechnology company applying novel human embryonic stem cell technologies in the emerging field of regenerative medicine. We believe that regenerative medicine has the potential to revolutionize the field by enabling scientists to produce human cells of any kind for use in a wide array of therapies.

  19. Adventures with Cell Phones

    Science.gov (United States)

    Kolb, Liz

    2011-01-01

    Teachers are finding creative ways to turn the basic cell phone from a digital distraction into a versatile learning tool. In this article, the author explains why cell phones are important in learning and suggests rather than banning them that they be integrated into learning. She presents activities that can be done on a basic cell phone with a…

  20. Cell phones and cancer

    Science.gov (United States)

    Cancer and cell phones; Do cell phones cause cancer? ... Several major studies show no link between cell phones and cancer at this time. However, since the information available is based on short-term studies, the impact of many years of ...

  1. Nanostructured Organic Solar Cells

    DEFF Research Database (Denmark)

    Radziwon, Michal Jędrzej; Rubahn, Horst-Günter; Madsen, Morten

    Recent forecasts for alternative energy generation predict emerging importance of supporting state of art photovoltaic solar cells with their organic equivalents. Despite their significantly lower efficiency, number of application niches are suitable for organic solar cells. This work reveals...... the principles of bulk heterojunction organic solar cells fabrication as well as summarises major differences in physics of their operation....

  2. Dazlin' pluripotent stem cells

    NARCIS (Netherlands)

    Welling, M.A.

    2014-01-01

    Pluripotent embryonic stem cells (ESCs) can be isolated from the inner cell mass (ICM) of blastocyst embryos and differentiate into all three germ layers in vitro. However, despite their similar origin, mouse embryonic stem cells represent a more naïve ICM-like pluripotent state whereas human embryo

  3. Mammalian Cell Culture Simplified.

    Science.gov (United States)

    Moss, Robert; Solomon, Sondra

    1991-01-01

    A tissue culture experiment that does not require elaborate equipment and that can be used to teach sterile technique, the principles of animal cell line maintenance, and the concept of cell growth curves is described. The differences between cancerous and normal cells can be highlighted. The procedure is included. (KR)

  4. Cell Culture Made Easy.

    Science.gov (United States)

    Dye, Frank J.

    1985-01-01

    Outlines steps to generate cell samples for observation and experimentation. The procedures (which use ordinary laboratory equipment) will establish a short-term primary culture of normal mammalian cells. Information on culture vessels and cell division and a list of questions to generate student interest and involvement in the topics are…

  5. SYNOVIAL CELL SARCOMA

    Directory of Open Access Journals (Sweden)

    M. Farzan

    1997-06-01

    Full Text Available Ten cases of synovial cell sarcoma are reported. The youngest patient was a 2'A years old boy with synovial cell sarcoma of the knee and the oldest one was a man with synovial cell sarcoma of the elbow.

  6. Embryonic Stem Cell Markers

    Directory of Open Access Journals (Sweden)

    Lan Ma

    2012-05-01

    Full Text Available Embryonic stem cell (ESC markers are molecules specifically expressed in ES cells. Understanding of the functions of these markers is critical for characterization and elucidation for the mechanism of ESC pluripotent maintenance and self-renewal, therefore helping to accelerate the clinical application of ES cells. Unfortunately, different cell types can share single or sometimes multiple markers; thus the main obstacle in the clinical application of ESC is to purify ES cells from other types of cells, especially tumor cells. Currently, the marker-based flow cytometry (FCM technique and magnetic cell sorting (MACS are the most effective cell isolating methods, and a detailed maker list will help to initially identify, as well as isolate ESCs using these methods. In the current review, we discuss a wide range of cell surface and generic molecular markers that are indicative of the undifferentiated ESCs. Other types of molecules, such as lectins and peptides, which bind to ESC via affinity and specificity, are also summarized. In addition, we review several markers that overlap with tumor stem cells (TSCs, which suggest that uncertainty still exists regarding the benefits of using these markers alone or in various combinations when identifying and isolating cells.

  7. Mouse Leydig Tumor Cells

    Directory of Open Access Journals (Sweden)

    Bo-Syong Pan

    2011-01-01

    Full Text Available Cordycepin is a natural pure compound extracted from Cordyceps sinensis (CS. We have demonstrated that CS stimulates steroidogenesis in primary mouse Leydig cell and activates apoptosis in MA-10 mouse Leydig tumor cells. It is highly possible that cordycepin is the main component in CS modulating Leydig cell functions. Thus, our aim was to investigate the steroidogenic and apoptotic effects with potential mechanism of cordycepin on MA-10 mouse Leydig tumor cells. Results showed that cordycepin significantly stimulated progesterone production in dose- and time-dependent manners. Adenosine receptor (AR subtype agonists were further used to treat MA-10 cells, showing that A1, A 2A , A 2B , and A3, AR agonists could stimulate progesterone production. However, StAR promoter activity and protein expression remained of no difference among all cordycepin treatments, suggesting that cordycepin might activate AR, but not stimulated StAR protein to regulate MA-10 cell steroidogenesis. Meanwhile, cordycepin could also induce apoptotic cell death in MA-10 cells. Moreover, four AR subtype agonists induced cell death in a dose-dependent manner, and four AR subtype antagonists could all rescue cell death under cordycepin treatment in MA-10 cells. In conclusion, cordycepin could activate adenosine subtype receptors and simultaneously induce steroidogenesis and apoptosis in MA-10 mouse Leydig tumor cells.

  8. Battery cell module

    Energy Technology Data Exchange (ETDEWEB)

    Shambaugh, J.S.

    1981-11-23

    A modular lithium battery having a plurality of cells, having electrical connecting means connecting the cells to output terminals, and venting means for releasing discharge byproducts to a chemical scrubber is disclosed. Stainless steel cell casings are potted in an aluminum modular case with syntactic foam and epoxy. The wall thickness resulting is about 0.5 inches.

  9. Aneuploidy in stem cells

    NARCIS (Netherlands)

    Garcia-Martinez, Jorge; Bakker, Bjorn; Schukken, Klaske M; Simon, Judith E; Foijer, Floris

    2016-01-01

    Stem cells hold enormous promise for regenerative medicine as well as for engineering of model systems to study diseases and develop new drugs. The discovery of protocols that allow for generating induced pluripotent stem cells (IPSCs) from somatic cells has brought this promise steps closer to real

  10. Solar Photovoltaic Cells.

    Science.gov (United States)

    Mickey, Charles D.

    1981-01-01

    Reviews information on solar radiation as an energy source. Discusses these topics: the key photovoltaic material; the bank theory of solids; conductors, semiconductors, and insulators; impurity semiconductors; solid-state photovoltaic cell operation; limitations on solar cell efficiency; silicon solar cells; cadmium sulfide/copper (I) sulfide…

  11. Molecular Mechanisms of HTLV-1 Cell-to-Cell Transmission

    Directory of Open Access Journals (Sweden)

    Christine Gross

    2016-03-01

    Full Text Available The tumorvirus human T-cell lymphotropic virus type 1 (HTLV-1, a member of the delta-retrovirus family, is transmitted via cell-containing body fluids such as blood products, semen, and breast milk. In vivo, HTLV-1 preferentially infects CD4+ T-cells, and to a lesser extent, CD8+ T-cells, dendritic cells, and monocytes. Efficient infection of CD4+ T-cells requires cell-cell contacts while cell-free virus transmission is inefficient. Two types of cell-cell contacts have been described to be critical for HTLV-1 transmission, tight junctions and cellular conduits. Further, two non-exclusive mechanisms of virus transmission at cell-cell contacts have been proposed: (1 polarized budding of HTLV-1 into synaptic clefts; and (2 cell surface transfer of viral biofilms at virological synapses. In contrast to CD4+ T-cells, dendritic cells can be infected cell-free and, to a greater extent, via viral biofilms in vitro. Cell-to-cell transmission of HTLV-1 requires a coordinated action of steps in the virus infectious cycle with events in the cell-cell adhesion process; therefore, virus propagation from cell-to-cell depends on specific interactions between cellular and viral proteins. Here, we review the molecular mechanisms of HTLV-1 transmission with a focus on the HTLV-1-encoded proteins Tax and p8, their impact on host cell factors mediating cell-cell contacts, cytoskeletal remodeling, and thus, virus propagation.

  12. Synthesis and Cytotoxicity of Chalcones and 5-Deoxyflavonoids

    Directory of Open Access Journals (Sweden)

    Jing Zhang

    2013-01-01

    Full Text Available Chalcones 1~8 and 5-deoxyflavonoids 9~22 were synthesized in good yields by aldol condensation, Algar-Flynn-Oyamada reaction, glycosidation, and deacetylation reaction, respectively, starting from 2-acetyl phenols substituted by methoxy or methoxymethoxy group and appropriately benzaldehydes substituted by methoxy, methoxymethoxy group, or chlorine. Among them, 13 and 17~22 are new compounds. The cytotoxicity bioassays of these chalcones and 5-deoxyflavonoids were screened using the sulforhodamine B (SRB protein staining method, and the results showed that compounds 2, 4, 5, 6, 10, 15, and 19 exhibited moderate cytotoxicity against the cancer cell line of MDA-MB-231, U251, BGC-823, and B16 in comparison with control drugs (HCPT, Vincristine, and Taxol.

  13. Fuel cell catalyst degradation

    DEFF Research Database (Denmark)

    Arenz, Matthias; Zana, Alessandro

    2016-01-01

    Fuel cells are an important piece in our quest for a sustainable energy supply. Although there are several different types of fuel cells, the by far most popular is the proton exchange membrane fuel cell (PEMFC). Among its many favorable properties are a short start up time and a high power density...... increasing focus. Activity of the catalyst is important, but stability is essential. In the presented perspective paper, we review recent efforts to investigate fuel cell catalysts ex-situ in electrochemical half-cell measurements. Due to the amount of different studies, this review has no intention to give...

  14. Mechanics rules cell biology

    Directory of Open Access Journals (Sweden)

    Wang James HC

    2010-07-01

    Full Text Available Abstract Cells in the musculoskeletal system are subjected to various mechanical forces in vivo. Years of research have shown that these mechanical forces, including tension and compression, greatly influence various cellular functions such as gene expression, cell proliferation and differentiation, and secretion of matrix proteins. Cells also use mechanotransduction mechanisms to convert mechanical signals into a cascade of cellular and molecular events. This mini-review provides an overview of cell mechanobiology to highlight the notion that mechanics, mainly in the form of mechanical forces, dictates cell behaviors in terms of both cellular mechanobiological responses and mechanotransduction.

  15. Transparent ultraviolet photovoltaic cells.

    Science.gov (United States)

    Yang, Xun; Shan, Chong-Xin; Lu, Ying-Jie; Xie, Xiu-Hua; Li, Bing-Hui; Wang, Shuang-Peng; Jiang, Ming-Ming; Shen, De-Zhen

    2016-02-15

    Photovoltaic cells have been fabricated from p-GaN/MgO/n-ZnO structures. The photovoltaic cells are transparent to visible light and can transform ultraviolet irradiation into electrical signals. The efficiency of the photovoltaic cells is 0.025% under simulated AM 1.5 illumination conditions, while it can reach 0.46% under UV illumination. By connecting several such photovoltaic cells in a series, light-emitting devices can be lighting. The photovoltaic cells reported in this Letter may promise the applications in glass of buildings to prevent UV irradiation and produce power for household appliances in the future.

  16. Dental pulp stem cells

    DEFF Research Database (Denmark)

    Ashri, N. Y.; Ajlan, S. A.; Aldahmash, Abdullah M.

    2015-01-01

    scaffold, and guided through signaling molecules. Dental pulp stem cells have been used in an increasing number of studies in dental tissue engineering. Those cells show mesenchymal (stromal) stem cell-like properties including self-renewal and multilineage differentiation potentials, aside from...... an updated review on dental pulp stem cells and their applications in periodontal regeneration, in combination with different scaffolds and growth factors.......Inflammatory periodontal disease is a major cause of loss of tooth-supporting structures. Novel approaches for regeneration of periodontal apparatus is an area of intensive research. Periodontal tissue engineering implies the use of appropriate regenerative cells, delivered through a suitable...

  17. Fuel Cell/Electrochemical Cell Voltage Monitor

    Science.gov (United States)

    Vasquez, Arturo

    2012-01-01

    A concept has been developed for a new fuel cell individual-cell-voltage monitor that can be directly connected to a multi-cell fuel cell stack for direct substack power provisioning. It can also provide voltage isolation for applications in high-voltage fuel cell stacks. The technology consists of basic modules, each with an 8- to 16-cell input electrical measurement connection port. For each basic module, a power input connection would be provided for direct connection to a sub-stack of fuel cells in series within the larger stack. This power connection would allow for module power to be available in the range of 9-15 volts DC. The relatively low voltage differences that the module would encounter from the input electrical measurement connection port, coupled with the fact that the module's operating power is supplied by the same substack voltage input (and so will be at similar voltage), provides for elimination of high-commonmode voltage issues within each module. Within each module, there would be options for analog-to-digital conversion and data transfer schemes. Each module would also include a data-output/communication port. Each of these ports would be required to be either non-electrical (e.g., optically isolated) or electrically isolated. This is necessary to account for the fact that the plurality of modules attached to the stack will normally be at a range of voltages approaching the full range of the fuel cell stack operating voltages. A communications/ data bus could interface with the several basic modules. Options have been identified for command inputs from the spacecraft vehicle controller, and for output-status/data feeds to the vehicle.

  18. Internalization of NK cells into tumor cells requires ezrin and leads to programmed cell-in-cell death

    Institute of Scientific and Technical Information of China (English)

    Shan Wang; Zhen Guo; Peng Xia; Tingting Liu; Jufang Wang; Shan Li; Lihua Sun; Jianxin Lu; Qian Wen; Mingqian Zhou; Li Ma; Xia Ding; Xiaoning Wang; Xuebiao Yao

    2009-01-01

    Cytotoxic lymphocytes are key players in the orchestration of immune response and elimination of defective cells. We have previously reported that natural killer (NK) cells enter target tumor cells, leading to either target cell death or self-destruction within tumor cells. However, it has remained elusive as to the fate of NK cells after internaliza-tion and whether the heterotypic cell-in-cell process is different from that of the homotypic cell-in-cell event recently named entosis. Here, we show that NK cells undergo a cell-in-cell process with the ultimate fate of apoptosis within tumor cells and reveal that the internalization process requires the actin cytoskeletal regulator, ezrin. To visualize how NK cells enter into tumor cells, we carried out real-time dual color imaging analyses of NK cell internalization into tumor cells. Surprisingly, most NK cells commit to programmed cell death after their entry into tumor cells, which is distinctively different from entosis observed in the homotypic cell-in-cell process. The apoptotic cell death of the internalized NK cells was evident by activation of caspase 3 and DNA fragmentation. Furthermore, NK cell death after internalization is attenuated by the caspase inhibitor, Z-VAD-FMK, confirming apoptosis as the mode of NK cell death within tumor cells. To determine protein factors essential for the entry of NK cells into tumor cells, we car-ried out siRNA-based knockdown analysis and discovered a critical role of ezrin in NK cell internalization. Impor-tantly, PKA-mediated phosphorylation of ezrin promotes the NK cell internalization process. Our findings suggest a novel regulatory mechanism by which ezrin governs NK cell internalization into tumor cells.

  19. Islet cell development.

    Science.gov (United States)

    Rojas, Anabel; Khoo, Adrian; Tejedo, Juan R; Bedoya, Francisco J; Soria, Bernat; Martín, Franz

    2010-01-01

    Over the last years, there has been great success in driving stem cells toward insulin-expressing cells. However, the protocols developed to date have some limitations, such as low reliability and low insulin production. The most successful protocols used for generation of insulin-producing cells from stem cells mimic in vitro pancreatic organogenesis by directing the stem cells through stages that resemble several pancreatic developmental stages. Islet cell fate is coordinated by a complex network of inductive signals and regulatory transcription factors that, in a combinatorial way, determine pancreatic organ specification, differentiation, growth, and lineage. Together, these signals and factors direct the progression from multipotent progenitor cells to mature pancreatic cells. Later in development and adult life, several of these factors also contribute to maintain the differentiated phenotype of islet cells. A detailed understanding of the processes that operate in the pancreas during embryogenesis will help us to develop a suitable source of cells for diabetes therapy. In this chapter, we will discuss the main transcription factors involved in pancreas specification and beta-cell formation.

  20. Cell biology. Metabolic control of cell death.

    Science.gov (United States)

    Green, Douglas R; Galluzzi, Lorenzo; Kroemer, Guido

    2014-09-19

    Beyond their contribution to basic metabolism, the major cellular organelles, in particular mitochondria, can determine whether cells respond to stress in an adaptive or suicidal manner. Thus, mitochondria can continuously adapt their shape to changing bioenergetic demands as they are subjected to quality control by autophagy, or they can undergo a lethal permeabilization process that initiates apoptosis. Along similar lines, multiple proteins involved in metabolic circuitries, including oxidative phosphorylation and transport of metabolites across membranes, may participate in the regulated or catastrophic dismantling of organelles. Many factors that were initially characterized as cell death regulators are now known to physically or functionally interact with metabolic enzymes. Thus, several metabolic cues regulate the propensity of cells to activate self-destructive programs, in part by acting on nutrient sensors. This suggests the existence of "metabolic checkpoints" that dictate cell fate in response to metabolic fluctuations. Here, we discuss recent insights into the intersection between metabolism and cell death regulation that have major implications for the comprehension and manipulation of unwarranted cell loss.

  1. Cell and Tissue Engineering

    CERN Document Server

    2012-01-01

    Cell and Tissue Engineering” introduces the principles and new approaches in cell and tissue engineering. It includes both the fundamentals and the current trends in cell and tissue engineering, in a way useful both to a novice and an expert in the field. The book is composed of 13 chapters all of which are written by the leading experts. It is organized to gradually assemble an insight in cell and tissue function starting form a molecular nano-level, extending to a cellular micro-level and finishing at the tissue macro-level. In specific, biological, physiological, biophysical, biochemical, medical, and engineering aspects are covered from the standpoint of the development of functional substitutes of biological tissues for potential clinical use. Topics in the area of cell engineering include cell membrane biophysics, structure and function of the cytoskeleton, cell-extracellular matrix interactions, and mechanotransduction. In the area of tissue engineering the focus is on the in vitro cultivation of ...

  2. Enteroendocrine cell types revisited

    DEFF Research Database (Denmark)

    Engelstoft, Maja S; Egerod, Kristoffer Lihme; Lund, Mari L

    2013-01-01

    The GI-tract is profoundly involved in the control of metabolism through peptide hormones secreted from enteroendocrine cells scattered throughout the gut mucosa. A large number of recently generated transgenic reporter mice have allowed for direct characterization of biochemical and cell...... biological properties of these previously highly elusive enteroendocrine cells. In particular the surprisingly broad co-expression of six functionally related hormones in the intestinal enteroendocrine cells indicates that it should be possible to control not only the hormone secretion but also the type...... and number of enteroendocrine cells. However, this will require a more deep understanding of the factors controlling differentiation, gene expression and specification of the enteroendocrine cells during their weekly renewal from progenitor cells in the crypts of the mucosa....

  3. Cell Factory Engineering.

    Science.gov (United States)

    Davy, Anne Mathilde; Kildegaard, Helene Faustrup; Andersen, Mikael Rørdam

    2017-03-22

    Rational approaches to modifying cells to make molecules of interest are of substantial economic and scientific interest. Most of these efforts aim at the production of native metabolites, expression of heterologous biosynthetic pathways, or protein expression. Reviews of these topics have largely focused on individual strategies or cell types, but collectively they fall under the broad umbrella of a growing field known as cell factory engineering. Here we condense >130 reviews and key studies in the art into a meta-review of cell factory engineering. We identified 33 generic strategies in the field, all applicable to multiple types of cells and products, and proven successful in multiple major cell types. These apply to three major categories: production of native metabolites and/or bioactives, heterologous expression of biosynthetic pathways, and protein expression. This meta-review provides general strategy guides for the broad range of applications of rational engineering of cell factories.

  4. Peripheral giant cell granuloma

    Directory of Open Access Journals (Sweden)

    Padam Narayan Tandon

    2012-01-01

    Full Text Available Peripheral giant cell granuloma or the so-called "giant cell epulis" is the most common oral giant cell lesion. It normally presents as a soft tissue purplish-red nodule consisting of multinucleated giant cells in a background of mononuclear stromal cells and extravasated red blood cells. This lesion probably does not represent a true neoplasm, but rather may be reactive in nature, believed to be stimulated by local irritation or trauma, but the cause is not certainly known. This article reports a case of peripheral giant cell granuloma arising at the maxillary anterior region in a 22-year-old female patient. The lesion was completely excised to the periosteum level and there is no residual or recurrent swelling or bony defect apparent in the area of biopsy after a follow-up period of 6 months.

  5. Cell viability assays: introduction.

    Science.gov (United States)

    Stoddart, Martin J

    2011-01-01

    The measurement of cell viability plays a fundamental role in all forms of cell culture. Sometimes it is the main purpose of the experiment, such as in toxicity assays. Alternatively, cell viability can be used to -correlate cell behaviour to cell number, providing a more accurate picture of, for example, anabolic -activity. There are wide arrays of cell viability methods which range from the most routine trypan blue dye exclusion assay to highly complex analysis of individual cells, such as using RAMAN microscopy. The cost, speed, and complexity of equipment required will all play a role in determining the assay used. This chapter aims to provide an overview of many of the assays available today.

  6. Involvement of plant stem cells or stem cell-like cells in dedifferentiation

    Directory of Open Access Journals (Sweden)

    Fangwei eJiang

    2015-11-01

    Full Text Available Dedifferentiation is the transformation of cells from a given differentiated state to a less differentiated or stem cell-like state. Stem cell-related genes play important roles in dedifferentiation, which exhibits similar histone modification and DNA methylation features to stem cell maintenance. Hence, stem cell-related factors possibly synergistically function to provide a specific niche beneficial to dedifferentiation. During callus formation in Arabidopsis petioles, cells adjacent to procambium cells (stem cell-like cells are dedifferentiated and survive more easily than other cell types. This finding indicates that stem cells or stem cell-like cells may influence the dedifferentiating niche. In this paper, we provide a brief overview of stem cell maintenance and dedifferentiation regulation. We also summarize current knowledge of genetic and epigenetic mechanisms underlying the balance between differentiation and dedifferentiation. Furthermore, we discuss the correlation of stem cells or stem cell-like cells with dedifferentiation.

  7. Stages of Renal Cell Cancer

    Science.gov (United States)

    ... cell cancer is a disease in which malignant (cancer) cells form in tubules of the kidney. Renal cell ... diagnosed, tests are done to find out if cancer cells have spread within the kidney or to other ...

  8. Cutaneous hamartoma with pagetoid cells.

    Science.gov (United States)

    Piérard-Franchimont, C; Dosal, F L; Estrada, J A; Piérard, G E

    1991-04-01

    We report an unusual cutaneous hamartoma with pagetoid cells characterized by the presence of intraepidermal cells resembling Toker's cells of the nipple. These cells were EMA positive and could be related to the histogenesis of some Paget's disease.

  9. Sickle Cell Disease (For Parents)

    Science.gov (United States)

    ... Old Feeding Your 1- to 2-Year-Old Sickle Cell Disease KidsHealth > For Parents > Sickle Cell Disease Print ... healthy, and productive lives. A Closer Look at Sickle Cell Disease The different types of sickle cell disease ...

  10. Membrane Cells for Brine Electrolysis.

    Science.gov (United States)

    Tingle, M.

    1982-01-01

    Membrane cells were developed as alternatives to mercury and diaphragm cells for the electrolysis of brine. Compares the three types of cells, focusing on the advantages and disadvantages of membrane cells. (JN)

  11. High Red Blood Cell Count

    Science.gov (United States)

    Symptoms High red blood cell count By Mayo Clinic Staff A high red blood cell count is an increase in oxygen-carrying cells in your bloodstream. Red blood cells transport oxygen from your lungs to tissues throughout ...

  12. PEROVSKITE SOLAR CELLS (REVIEW ARTICLE)

    OpenAIRE

    Benli, Deniz Ahmet

    2015-01-01

    A solar cell is a device that converts sunlight into electricity. There are different types of solar cells but this report mainly focuses on a type of new generation solar cell that has the name organo-metal halide perovskite, shortly perovskite solar cells. In this respect, the efficiency of power conversion is taken into account to replace the dominancy of traditional and second generation solar cell fields by perovskite solar cells. Perovskite solar cell is a type of solar cell including a...

  13. Cell to substratum and cell to cell interactions of microalgae.

    Science.gov (United States)

    Ozkan, Altan; Berberoglu, Halil

    2013-12-01

    This paper reports the cell to substratum and cell to cell interactions of a diverse group of microalgae based on the Extended Derjaguin, Landau, Verwey, Overbeek (XDLVO) approach using the previously reported physico-chemical surface properties. The microalgae included 10 different species of green algae and diatoms from both freshwater and saltwater environments while the substrata included glass, indium-tin oxide (ITO), stainless steel, polycarbonate, polyethylene, and polystryrene. The results indicated that acid-base interactions were the dominating mechanism of interaction for microalgae. For green algae, if at least one of the interacting surfaces was hydrophobic, adhesion at primary minimum was predicted without any energy barrier. However, most diatom systems featured energy barriers for adhesion due to repulsive van der Waals interactions. The results reported in this study are expected to provide useful data and insight into the interaction mechanisms of microalgae cells with each other and with substrata for a number of practical applications including prevention of biofouling of photobioreactors and other man-made surfaces, promotion of biofilm formation in algal biofilm photobioreactors, and developing bioflocculation strategies for energy efficient harvesting of algal biomass. Particularly, Botryococcus braunii and Cerithiopsis fusiformis were identified as promising species for biofloccuation and biofilm formation in freshwater and saltwater aquatic systems, respectively. Finally, based on the observed trends in this study, use of hydrophilic algae and hydrophilic coatings over surfaces are recommended for minimizing biofouling in aquatic systems.

  14. Biology of Schwann cells.

    Science.gov (United States)

    Kidd, Grahame J; Ohno, Nobuhiko; Trapp, Bruce D

    2013-01-01

    The fundamental roles of Schwann cells during peripheral nerve formation and regeneration have been recognized for more than 100 years, but the cellular and molecular mechanisms that integrate Schwann cell and axonal functions continue to be elucidated. Derived from the embryonic neural crest, Schwann cells differentiate into myelinating cells or bundle multiple unmyelinated axons into Remak fibers. Axons dictate which differentiation path Schwann cells follow, and recent studies have established that axonal neuregulin1 signaling via ErbB2/B3 receptors on Schwann cells is essential for Schwann cell myelination. Extracellular matrix production and interactions mediated by specific integrin and dystroglycan complexes are also critical requisites for Schwann cell-axon interactions. Myelination entails expansion and specialization of the Schwann cell plasma membrane over millimeter distances. Many of the myelin-specific proteins have been identified, and transgenic manipulation of myelin genes have provided novel insights into myelin protein function, including maintenance of axonal integrity and survival. Cellular events that facilitate myelination, including microtubule-based protein and mRNA targeting, and actin based locomotion, have also begun to be understood. Arguably, the most remarkable facet of Schwann cell biology, however, is their vigorous response to axonal damage. Degradation of myelin, dedifferentiation, division, production of axonotrophic factors, and remyelination all underpin the substantial regenerative capacity of the Schwann cells and peripheral nerves. Many of these properties are not shared by CNS fibers, which are myelinated by oligodendrocytes. Dissecting the molecular mechanisms responsible for the complex biology of Schwann cells continues to have practical benefits in identifying novel therapeutic targets not only for Schwann cell-specific diseases but other disorders in which axons degenerate.

  15. Embryonic stem cell-somatic cell fusion and postfusion enucleation.

    Science.gov (United States)

    Sumer, Huseyin; Verma, Paul J

    2015-01-01

    Embryonic stem (ES) cells are able to reprogram somatic cells following cell fusion. The resulting cell hybrids have been shown to have similar properties to pluripotent cells. It has also been shown that transcriptional changes can occur in a heterokaryon, without nuclear hybridization. However it is unclear whether these changes can be sustained following removal of the dominant ES nucleus. In this chapter, methods are described for the cell fusion of mouse tetraploid ES cells with somatic cells and enrichment of the resulting heterokaryons. We next describe the conditions for the differential removal of the ES cell nucleus, allowing for the recovery of somatic cells.

  16. Isolation of rare cancer cells from blood cells using dielectrophoresis.

    Science.gov (United States)

    Salmanzadeh, Alireza; Sano, Michael B; Shafiee, Hadi; Stremler, Mark A; Davalos, Rafael V

    2012-01-01

    In this study, we investigate the application of contactless dielectrophoresis (cDEP) for isolating cancer cells from blood cells. Devices with throughput of 0.2 mL/hr (equivalent to sorting 3×10(6) cells per minute) were used to trap breast cancer cells while allowing blood cells through. We have shown that this technique is able to isolate cancer cells in concentration as low as 1 cancer cell per 10(6) hematologic cells (equivalent to 1000 cancer cells in 1 mL of blood). We achieved 96% trapping of the cancer cells at 600 kHz and 300 V(RMS).

  17. Cell-Substrate Adhesion by Amoeboid Cells

    Science.gov (United States)

    Flanders, Bret; Panta, Krishna

    Amoeboid migration is a rapid (10 μm min-1) mode of migration that some tumor cells exhibit. To permit such rapid movement, the adhesive contacts between the cell and the substrate must be relatively short-lived and weak. In this study, we investigate the basic adhesive character of amoeboid cells (D. discoideum) in contact with silanized glass substrates. We observe the initiation and spreading of the adhesive contacts that these cells establish as they settle under gravity onto the substrate and relax towards mechanical equilibrium. The use of interference reflection microscopy and cellular tethering measurements have allowed us to determine the basic adhesive properties of the cell: the membrane-medium interfacial energy; the bending modulus; the equilibrium contact angle; and the work of adhesion. We find the time scale on which settling occurs to be longer than expected. Implications of these results on adhesion and migration will be discussed. The authors are grateful for support from NSF (CBET-1451903) and NIH (1R21EY026392).

  18. Aneuploidy in stem cells

    Institute of Scientific and Technical Information of China (English)

    Jorge; Garcia-Martinez; Bjorn; Bakker; Klaske; M; Schukken; Judith; E; Simon; Floris; Foijer

    2016-01-01

    Stem cells hold enormous promise for regenerative medicine as well as for engineering of model systems to study diseases and develop new drugs. The discovery of protocols that allow for generating induced pluripotent stem cells(IPSCs) from somatic cells has brought this promise steps closer to reality. However,as somatic cells might have accumulated various chromosomal abnormalities,including aneuploidies throughout their lives,the resulting IPSCs might no longer carry the perfect blueprint for the tissue to be generated,or worse,become at risk of adopting a malignant fate. In this review,we discuss the contribution of aneuploidy to healthy tissues and how aneuploidy can lead to disease. Furthermore,we review the differences between how somatic cells and stem cells respond to aneuploidy.

  19. Mechanical plasticity of cells

    Science.gov (United States)

    Bonakdar, Navid; Gerum, Richard; Kuhn, Michael; Spörrer, Marina; Lippert, Anna; Schneider, Werner; Aifantis, Katerina E.; Fabry, Ben

    2016-10-01

    Under mechanical loading, most living cells show a viscoelastic deformation that follows a power law in time. After removal of the mechanical load, the cell shape recovers only incompletely to its original undeformed configuration. Here, we show that incomplete shape recovery is due to an additive plastic deformation that displays the same power-law dynamics as the fully reversible viscoelastic deformation response. Moreover, the plastic deformation is a constant fraction of the total cell deformation and originates from bond ruptures within the cytoskeleton. A simple extension of the prevailing viscoelastic power-law response theory with a plastic element correctly predicts the cell behaviour under cyclic loading. Our findings show that plastic energy dissipation during cell deformation is tightly linked to elastic cytoskeletal stresses, which suggests the existence of an adaptive mechanism that protects the cell against mechanical damage.

  20. Cell Factory Engineering

    DEFF Research Database (Denmark)

    Davy, Anne Mathilde; Kildegaard, Helene Faustrup; Andersen, Mikael Rørdam

    2017-01-01

    Rational approaches to modifying cells to make molecules of interest are of substantial economic and scientific interest. Most of these efforts aim at the production of native metabolites, expression of heterologous biosynthetic pathways, or protein expression. Reviews of these topics have largely...... focused on individual strategies or cell types, but collectively they fall under the broad umbrella of a growing field known as cell factory engineering. Here we condense >130 reviews and key studies in the art into a meta-review of cell factory engineering. We identified 33 generic strategies...... in the field, all applicable to multiple types of cells and products, and proven successful in multiple major cell types. These apply to three major categories: production of native metabolites and/or bioactives, heterologous expression of biosynthetic pathways, and protein expression. This meta...

  1. NCAM regulates cell motility

    DEFF Research Database (Denmark)

    Prag, Søren; Lepekhin, Eugene A; Kolkova, Kateryna

    2002-01-01

    Cell migration is required during development of the nervous system. The regulatory mechanisms for this process, however, are poorly elucidated. We show here that expression of or exposure to the neural cell adhesion molecule (NCAM) strongly affected the motile behaviour of glioma cells...... independently of homophilic NCAM interactions. Expression of the transmembrane 140 kDa isoform of NCAM (NCAM-140) caused a significant reduction in cellular motility, probably through interference with factors regulating cellular attachment, as NCAM-140-expressing cells exhibited a decreased attachment...... to a fibronectin substratum compared with NCAM-negative cells. Ectopic expression of the cytoplasmic part of NCAM-140 also inhibited cell motility, presumably via the non-receptor tyrosine kinase p59(fyn) with which NCAM-140 interacts. Furthermore, we showed that the extracellular part of NCAM acted as a paracrine...

  2. Fish germ cells

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Fish, like many other animals, have two major cell lineages, namely the germline and soma. The germ-soma separation is one of the earliest events of embryonic development. Germ cells can be specifically labeled and isolated for culture and transplan-tation, providing tools for reproduction of endangered species in close relatives, such as surrogate production of trout in salmon. Haploid cell cultures, such as medaka haploid embryonic stem cells have recently been obtained, which are capable of mimicking sperm to produce fertile offspring, upon nuclear being directly transferred into normal eggs. Such fish originated from a mosaic oocyte that had a haploid meiotic nucleus and a transplanted haploid mitotic cell culture nucleus. The first semi-cloned fish is Holly. Here we review the current status and future directions of understanding and manipulating fish germ cells in basic research and reproductive technology.

  3. Trafficking and cell migration.

    Science.gov (United States)

    Ulrich, Florian; Heisenberg, Carl-Philipp

    2009-07-01

    The migration of single cells and epithelial sheets is of great importance for gastrulation and organ formation in developing embryos and, if misregulated, can have dire consequences e.g. during cancer metastasis. A keystone of cell migration is the regulation of adhesive contacts, which are dynamically assembled and disassembled via endocytosis. Here, we discuss some of the basic concepts about the function of endocytic trafficking during cell migration: transport of integrins from the cell rear to the leading edge in fibroblasts; confinement of signalling to the front of single cells by endocytic transport of growth factors; regulation of movement coherence in multicellular sheets by cadherin turnover; and shaping of extracellular chemokine gradients. Taken together, endocytosis enables migrating cells and tissues to dynamically modulate their adhesion and signalling, allowing them to efficiently migrate through their extracellular environment.

  4. Gingival plasma cell granuloma

    Directory of Open Access Journals (Sweden)

    Amitkumar B Pandav

    2012-01-01

    Full Text Available Plasma cell granuloma, also known as inflammatory pseudotumor is a tumor-like lesion that manifests primarily in the lungs. But it may occur in various other anatomic locations like orbit, head and neck, liver and rarely in the oral cavity. We here report an exceedingly rare case of gingival plasma cell granuloma in a 58 year old woman who presented with upper gingival polypoidal growth. The histopathological examination revealed a mass composed of proliferation of benign spindle mesenchymal cells in a loose myxoid and fibrocollagenous stroma along with dense infiltrate of chronic inflammatory cells predominantly containing plasma cells. Immunohistochemistry for kappa and lambda light chains showed a polyclonal staining pattern confirming a diagnosis of plasma cell granuloma.

  5. Gingival plasma cell granuloma

    Directory of Open Access Journals (Sweden)

    Phadnaik Mangesh

    2010-01-01

    Full Text Available Plasma cell granuloma is a rare reactive lesion composed of polyclonal plasma cells. It manifests primarily in the lungs, but may occur in various other anatomic locations like the oral cavity. Intraoral plasma cell granulomas involving the tongue, lip, oral mucosa and gingiva have been reported in the past. This case presents a 54-year-old female with chronic periodontitis and mandibular anterior gingival overgrowth treated by Phase I therapy (scaling and root planing and excisional biopsy. Histological examination revealed inflammatory cell infiltrate containing sheets of plasma cells. Immunohistochemistry for kappa and lambda light chains showed a polyclonal staining pattern confirming a diagnosis of plasma cell granuloma. This case highlights the need to biopsy for unusual lesions to rule out potential neoplasms.

  6. Induced pluripotent stem cells

    Institute of Scientific and Technical Information of China (English)

    Siddhartha Bhowmik; LI Yong

    2011-01-01

    Induced pluripotent stem (iPS) cells are a recent development which has brought a promise of great therapeutic values. The previous technique of somatic cell nuclear transfer (SCNT) has been ineffective in humans. Recent discoveries show that human fibroblasts can be reprogrammed by a transient over expression of a small number of genes; they can undergo induced pluripotency. iPS were first produced in 2006. By 2008, work was underway to remove the potential oncogenes from their structure. In 2009, protein iPS (piPS) cells were discovered. Surface markers and reporter genes play an important role in stem cell research. Clinical applications include generation of self renewing stem cells, tissue replacement and many more. Stem cell therapy has the ability to dramatically change the treatment of human diseases.

  7. Myoepithelial cells in pathology.

    Science.gov (United States)

    Balachander, N; Masthan, K M K; Babu, N Aravindha; Anbazhagan, V

    2015-04-01

    Myoepithelial cells are a normal constituent of the salivary acini and ducts and are found between the epithelial cells and the basement membrane. Microscopically myoepithelial cells are thin and spindle-shaped and ultrastructurally they possess a number of Cytoplasmic processes that extend between and over the acinar and ductal-lining cells, and they show features of both smooth muscle and epithelium. They play a vital role during expulsion of saliva and regulates the electrolytic exchange. They also perform as tumor suppressors and are considered to play a very important role in differentiation of various salivary gland tumors and help in the diagnosis of tumors. Neoplastic myoepithelial cells in both benign and malignant tumors can take numerous forms including epithelioid, plasmacytoid, spindle and clear cell variant, and this variability largely accounts for difficulties in histopathological diagnosis.

  8. Myoepithelial cells in pathology

    Directory of Open Access Journals (Sweden)

    N Balachander

    2015-01-01

    Full Text Available Myoepithelial cells are a normal constituent of the salivary acini and ducts and are found between the epithelial cells and the basement membrane. Microscopically myoepithelial cells are thin and spindle-shaped and ultrastructurally they possess a number of Cytoplasmic processes that extend between and over the acinar and ductal-lining cells, and they show features of both smooth muscle and epithelium. They play a vital role during expulsion of saliva and regulates the electrolytic exchange. They also perform as tumor suppressors and are considered to play a very important role in differentiation of various salivary gland tumors and help in the diagnosis of tumors. Neoplastic myoepithelial cells in both benign and malignant tumors can take numerous forms including epithelioid, plasmacytoid, spindle and clear cell variant, and this variability largely accounts for difficulties in histopathological diagnosis.

  9. Cytoskeleton and Cell Motility

    CERN Document Server

    Risler, Thomas

    2011-01-01

    The present article is an invited contribution to the Encyclopedia of Complexity and System Science, Robert A. Meyers Ed., Springer New York (2009). It is a review of the biophysical mechanisms that underly cell motility. It mainly focuses on the eukaryotic cytoskeleton and cell-motility mechanisms. Bacterial motility as well as the composition of the prokaryotic cytoskeleton is only briefly mentioned. The article is organized as follows. In Section III, I first present an overview of the diversity of cellular motility mechanisms, which might at first glance be categorized into two different types of behaviors, namely "swimming" and "crawling". Intracellular transport, mitosis - or cell division - as well as other extensions of cell motility that rely on the same essential machinery are briefly sketched. In Section IV, I introduce the molecular machinery that underlies cell motility - the cytoskeleton - as well as its interactions with the external environment of the cell and its main regulatory pathways. Sec...

  10. Mammary gland stem cells

    DEFF Research Database (Denmark)

    Fridriksdottir, Agla J R; Petersen, Ole W; Rønnov-Jessen, Lone

    2011-01-01

    Distinct subsets of cells, including cells with stem cell-like properties, have been proposed to exist in normal human breast epithelium and breast carcinomas. The cellular origins of epithelial cells contributing to gland development, tissue homeostasis and cancer are, however, still poorly...... and differences between mouse and human gland development with particular emphasis on the identity and localization of stem cells, and the influence of the surrounding microenvironment. It is concluded that while recent advances in the field have contributed immense insight into how the normal mammary gland...... develops and is maintained, significant discrepancies exist between the mouse and human gland which should be taken into consideration in current and future models of mammary stem cell biology....

  11. Differentiated human stem cells resemble fetal, not adult, β cells.

    Science.gov (United States)

    Hrvatin, Sinisa; O'Donnell, Charles W; Deng, Francis; Millman, Jeffrey R; Pagliuca, Felicia Walton; DiIorio, Philip; Rezania, Alireza; Gifford, David K; Melton, Douglas A

    2014-02-25

    Human pluripotent stem cells (hPSCs) have the potential to generate any human cell type, and one widely recognized goal is to make pancreatic β cells. To this end, comparisons between differentiated cell types produced in vitro and their in vivo counterparts are essential to validate hPSC-derived cells. Genome-wide transcriptional analysis of sorted insulin-expressing (INS(+)) cells derived from three independent hPSC lines, human fetal pancreata, and adult human islets points to two major conclusions: (i) Different hPSC lines produce highly similar INS(+) cells and (ii) hPSC-derived INS(+) (hPSC-INS(+)) cells more closely resemble human fetal β cells than adult β cells. This study provides a direct comparison of transcriptional programs between pure hPSC-INS(+) cells and true β cells and provides a catalog of genes whose manipulation may convert hPSC-INS(+) cells into functional β cells.

  12. Direct hydrocarbon fuel cells

    Science.gov (United States)

    Barnett, Scott A.; Lai, Tammy; Liu, Jiang

    2010-05-04

    The direct electrochemical oxidation of hydrocarbons in solid oxide fuel cells, to generate greater power densities at lower temperatures without carbon deposition. The performance obtained is comparable to that of fuel cells used for hydrogen, and is achieved by using novel anode composites at low operating temperatures. Such solid oxide fuel cells, regardless of fuel source or operation, can be configured advantageously using the structural geometries of this invention.

  13. Lymphomas of large cells.

    Science.gov (United States)

    Staples, W G; Gétaz, E P

    1977-09-03

    Historial aspects of the classification of large-cell lymphomas are described. Immunological characterization of the lymphomas has been made possible by identification of T and B lymphocytes according to their cell membrane surface characteristics. The pathogenesis of lymphomas has been clarified by the germinal (follicular) centre cell concepts of Lennert and Lukes and Collins. The various classifications are presented and compared. Whether these subdivisions will have any relevance in the clinical context remains to be seen.

  14. Immobilized Cell Research

    Science.gov (United States)

    1990-10-31

    beads, the plasmid is twice as stable as in cells In a process where immobilized cells produce material grown in continuous culture over 200...carrageenan) or chemically cross-linked, or- Penicillium chrysogenum than in washed freely suspended ganic polymer (Ca-alginate, polyacrylamide, and mycelium ...these materials are formed into the freely suspended cells stopped after 6 days. If the beads of several millimeters in diameter by allowing the

  15. Cell Wall Proteome

    OpenAIRE

    Boudart, Georges; Minic, Zoran; Albenne, Cécile; Canut, Hervé; Jamet, Elisabeth; Pont-Lezica, Rafael F

    2007-01-01

    In this chapter, we will focus on the contribution of proteomics to the identification and determination of the structure and function of CWPs as well as discussing new perspectives in this area. The great variety of proteins found in the plant cell wall is described. Some families, such as glycoside hydrolases, proteases, lectins, and inhibitors of cell wall modifying enzymes, are discussed in detail. Examples of the use of proteomic techniques to elucidate the structure of various cell wall...

  16. Systems cell biology.

    Science.gov (United States)

    Mast, Fred D; Ratushny, Alexander V; Aitchison, John D

    2014-09-15

    Systems cell biology melds high-throughput experimentation with quantitative analysis and modeling to understand many critical processes that contribute to cellular organization and dynamics. Recently, there have been several advances in technology and in the application of modeling approaches that enable the exploration of the dynamic properties of cells. Merging technology and computation offers an opportunity to objectively address unsolved cellular mechanisms, and has revealed emergent properties and helped to gain a more comprehensive and fundamental understanding of cell biology.

  17. Origins of pluripotent stem cells.

    Science.gov (United States)

    Roelen, B A J; Chuva De Sousa Lopes, S M

    2011-08-01

    Different types of pluripotent stem cells can be identified and cultured in vitro. Here an overview is presented of the various pluripotent stem cells types. Embryonal carcinoma (EC) cells that have been cultured in vitro provided the groundwork for future pluripotent cell cultures. Conditions established for these cells such as culture on a feeder layer of mouse embryonic fibroblasts and the importance of fetal calf serum were initially also used for the culture of mouse embryonic stem (ES) cells derived from the inner cell masses of blastocysts. Embryonic stem cells derived from human blastocysts were found to require different conditions and are cultured in the presence of activin and basic fibroblast growth factor. Recently pluripotent stem cells have also been derived from mouse peri-implantation epiblasts. Since these epiblast stem cells (EpiSCs) require the same conditions as the human ES cells it has been suggested that human ES cells are more similar to mouse EpiSCs than to mouse ES cells. Pluripotent cell lines have also been derived from migratory primordial germ cells and spermatogonial stem cells. The creation of pluripotent stem cells from adult cells by the introduction of reprogramming transcription factors, so-called induced pluripotent stem (iPS) cells allowed the derivation of patient-specific pluripotent stem cells without the need of creation of a human blastocyst after cloning by somatic cells nuclear transfer. Recently it has become clear however that iPS cells may be quite different to ES cells in terms of epigenetics.

  18. Beta cell dynamics: beta cell replenishment, beta cell compensation and diabetes.

    Science.gov (United States)

    Cerf, Marlon E

    2013-10-01

    Type 2 diabetes, characterized by persistent hyperglycemia, arises mostly from beta cell dysfunction and insulin resistance and remains a highly complex metabolic disease due to various stages in its pathogenesis. Glucose homeostasis is primarily regulated by insulin secretion from the beta cells in response to prevailing glycemia. Beta cell populations are dynamic as they respond to fluctuating insulin demand. Beta cell replenishment and death primarily regulate beta cell populations. Beta cells, pancreatic cells, and extra-pancreatic cells represent the three tiers for replenishing beta cells. In rodents, beta cell self-replenishment appears to be the dominant source for new beta cells supported by pancreatic cells (non-beta islet cells, acinar cells, and duct cells) and extra-pancreatic cells (liver, neural, and stem/progenitor cells). In humans, beta cell neogenesis from non-beta cells appears to be the dominant source of beta cell replenishment as limited beta cell self-replenishment occurs particularly in adulthood. Metabolic states of increased insulin demand trigger increased insulin synthesis and secretion from beta cells. Beta cells, therefore, adapt to support their physiology. Maintaining physiological beta cell populations is a strategy for targeting metabolic states of persistently increased insulin demand as in diabetes.

  19. Rapid cooled lens cell

    Science.gov (United States)

    Stubbs, David M.; Hsu, Ike C.

    1991-12-01

    This paper describes the optomechanical design, thermal analysis, fabrication, and test evaluation processes followed in developing a rapid cooled, infrared lens cell. Thermal analysis was the key engineering discipline exercised in the design phase. The effect of thermal stress on the lens, induced by rapid cooling of the lens cell, was investigated. Features of this lens cell that minimized the thermal stress will be discussed in a dedicated section. The results of thermal analysis on the selected lens cell design and the selection of the flow channel design in the heat exchanger will be discussed. Throughout the paper engineering drawings, illustrations, analytical results, and photographs of actual hardware are presented.

  20. Cell sorting in development.

    Science.gov (United States)

    Krens, S F Gabby; Heisenberg, Carl-Philipp

    2011-01-01

    During the development of multicellular organisms, cell fate specification is followed by the sorting of different cell types into distinct domains from where the different tissues and organs are formed. Cell sorting involves both the segregation of a mixed population of cells with different fates and properties into distinct domains, and the active maintenance of their segregated state. Because of its biological importance and apparent resemblance to fluid segregation in physics, cell sorting was extensively studied by both biologists and physicists over the last decades. Different theories were developed that try to explain cell sorting on the basis of the physical properties of the constituent cells. However, only recently the molecular and cellular mechanisms that control the physical properties driving cell sorting, have begun to be unraveled. In this review, we will provide an overview of different cell-sorting processes in development and discuss how these processes can be explained by the different sorting theories, and how these theories in turn can be connected to the molecular and cellular mechanisms driving these processes.

  1. Red cell enzymes.

    Science.gov (United States)

    Paniker, N V

    1975-03-01

    As compared to other cells of the body, the mammalian red cell has one of the simplest structural organizations. As a result, this cell has been extensively used in studies involving the structure, function, and integrity of cell membranes as well as cytoplasmic events. Additionally, the metabolic activities of the red blood cell are also relatively simple. During the past quarter century or so, an ocean of knowledge has been gathered on various aspects of red cell metabolism and function. The fields of enzymes, hemoglobin, membrane, and metabolic products comprise the major portion of this knowledge. These advances have made valuable contributions to biochemistry and medicine. Despite these favorable aspects of this simple, anucleated cell, it must be conceded that our knowledge about the red cell is far from complete. We are still in the dark concerning the mechanism involved in several aspects of its membrane, hemoglobin, enzymes, and a large number of other constituents. For example, a large number of enzymes with known catalytic activity but with unknown function have eluded investigators despite active pursuit. This review will be a consolidation of our present knowledge of human red cell enzymes, with particular reference to their usefulness in the diagnosis and therapy of disease. Owing to the multitude of publications by prominent investigators on each of the approximately 50 enzymes discussed in this review, it was impossible to cite a majority of them.

  2. Littoral Cells 2005

    Data.gov (United States)

    California Department of Resources — Littoral cells along the California Coast. Originally digitized by Melanie Coyne from the Assessment and Atlas of Shoreline Erosion Along the California Coast...

  3. [Endothelial cell adhesion molecules].

    Science.gov (United States)

    Ivanov, A N; Norkin, I A; Puchin'ian, D M; Shirokov, V Iu; Zhdanova, O Iu

    2014-01-01

    The review presents current data concerning the functional role of endothelial cell adhesion molecules belonging to different structural families: integrins, selectins, cadherins, and the immunoglobulin super-family. In this manuscript the regulatory mechanisms and factors of adhesion molecules expression and distribution on the surface of endothelial cells are discussed. The data presented reveal the importance of adhesion molecules in the regulation of structural and functional state of endothelial cells in normal conditions and in pathology. Particular attention is paid to the importance of these molecules in the processes of physiological and pathological angiogenesis, regulation of permeability of the endothelial barrier and cell transmigration.

  4. Analysing immune cell migration.

    Science.gov (United States)

    Beltman, Joost B; Marée, Athanasius F M; de Boer, Rob J

    2009-11-01

    The visualization of the dynamic behaviour of and interactions between immune cells using time-lapse video microscopy has an important role in modern immunology. To draw robust conclusions, quantification of such cell migration is required. However, imaging experiments are associated with various artefacts that can affect the estimated positions of the immune cells under analysis, which form the basis of any subsequent analysis. Here, we describe potential artefacts that could affect the interpretation of data sets on immune cell migration. We propose how these errors can be recognized and corrected, and suggest ways to prevent the data analysis itself leading to biased results.

  5. Microencapsulation Of Living Cells

    Science.gov (United States)

    Chang, Manchium; Kendall, James M.; Wang, Taylor G.

    1989-01-01

    In experimental technique, living cells and other biological materials encapsulated within submillimeter-diameter liquid-filled spheres. Sphere material biocompatible, tough, and compliant. Semipermeable, permitting relatively small molecules to move into and out of sphere core but preventing passage of large molecules. New technique promises to make such spherical capsules at high rates and in uniform, controllable sizes. Capsules injected into patient through ordinary hypodermic needle. Promising application for technique in treatment of diabetes. Also used to encapsulate pituitary cells and thyroid hormone adrenocortical cells for treatment of other hormonal disorders, to encapsulate other secreting cells for transplantation, and to package variety of pharmaceutical products and agricultural chemicals for controlled release.

  6. Nanocrystal Solar Cells

    Energy Technology Data Exchange (ETDEWEB)

    Gur, Ilan [Univ. of California, Berkeley, CA (United States)

    2006-01-01

    This dissertation presents the results of a research agenda aimed at improving integration and stability in nanocrystal-based solar cells through advances in active materials and device architectures. The introduction of 3-dimensional nanocrystals illustrates the potential for improving transport and percolation in hybrid solar cells and enables novel fabrication methods for optimizing integration in these systems. Fabricating cells by sequential deposition allows for solution-based assembly of hybrid composites with controlled and well-characterized dispersion and electrode contact. Hyperbranched nanocrystals emerge as a nearly ideal building block for hybrid cells, allowing the controlled morphologies targeted by templated approaches to be achieved in an easily fabricated solution-cast device. In addition to offering practical benefits to device processing, these approaches offer fundamental insight into the operation of hybrid solar cells, shedding light on key phenomena such as the roles of electrode-contact and percolation behavior in these cells. Finally, all-inorganic nanocrystal solar cells are presented as a wholly new cell concept, illustrating that donor-acceptor charge transfer and directed carrier diffusion can be utilized in a system with no organic components, and that nanocrystals may act as building blocks for efficient, stable, and low-cost thin-film solar cells.

  7. Assessment of cell viability.

    Science.gov (United States)

    Johnson, Simon; Nguyen, Vy; Coder, David

    2013-01-01

    Cell viability may be judged by morphological changes or by changes in membrane permeability and/or physiological state inferred from the exclusion of certain dyes or the uptake and retention of others. This unit presents methods based on dye exclusion, esterase activity, and mitochondrial membrane potential, as well as protocols for determining the pre-fixation viability of fixed cells either before or after fixation with amine-reactive dyes suitable for a range of excitation wavelengths. Membrane-impermeable dead cell and live cell dyes as well as dye-exclusion procedures for microscopy are also included.

  8. Dedifferentiated adipocyte-derived progeny cells (DFAT cells)

    OpenAIRE

    Wei, Shengjuan; Zan, Linsen; Hausman, Gary J.; Rasmussen, Theodore P; Bergen, Werner G.; Dodson, Michael V.

    2013-01-01

    Analyses of mature adipocytes have shown that they possess a reprogramming ability in vitro, which is associated with dedifferentiation. The subsequent dedifferentiated fat cells (DFAT cells) are multipotent and can differentiate into adipocytes and other cell types as well. Mature adipocytes can be easily obtained by biopsy, and the cloned progeny cells are homogeneous in vitro. Therefore, DFAT cells (a new type of stem cell) may provide an excellent source of cells for tissue regeneration, ...

  9. A focus on parietal cells as a renewing cell population

    Institute of Scientific and Technical Information of China (English)

    Sherif; M; Karam

    2010-01-01

    The fact that the acidsecreting parietal cells undergo continuous renewal has been ignored by many gastroenterologists and cell biologists. In the past, it was thought that these cells were static. However, by using 3Hthymidine radioautography in combination with electron microscopy, it was possible to demonstrate that parietal cells belong to a continuously renewing epithelial cell lineage. In the gastric glands, stem cells anchored in the isthmus region are responsible for the production of parietal cells...

  10. Regulation of B Cell to Plasma Cell Transition within the Follicular B Cell Response.

    Science.gov (United States)

    Nera, K-P; Kyläniemi, M K; Lassila, O

    2015-09-01

    Persistent humoral immunity depends on the follicular B cell response and on the generation of somatically mutated high-affinity plasma cells and memory B cells. Upon activation by an antigen, cognately activated follicular B cells and follicular T helper (TFH ) cells initiate germinal centre (GC) reaction during which high-affinity effector cells are generated. The differentiation of activated follicular B cells into plasma cells and memory B cells is guided by complex selection events, both at the cellular and molecular level. The transition of B cell into a plasma cell during the GC response involves alterations in the microenvironment and developmental state of the cell, which are guided by cell-extrinsic signals. The developmental cell fate decisions in response to these signals are coordinated by cell-intrinsic gene regulatory network functioning at epigenetic, transcriptional and post-transcriptional levels.

  11. Regulation of beta cell replication

    DEFF Research Database (Denmark)

    Lee, Ying C; Nielsen, Jens Høiriis

    2008-01-01

    Beta cell mass, at any given time, is governed by cell differentiation, neogenesis, increased or decreased cell size (cell hypertrophy or atrophy), cell death (apoptosis), and beta cell proliferation. Nutrients, hormones and growth factors coupled with their signalling intermediates have been...... suggested to play a role in beta cell mass regulation. In addition, genetic mouse model studies have indicated that cyclins and cyclin-dependent kinases that determine cell cycle progression are involved in beta cell replication, and more recently, menin in association with cyclin-dependent kinase...... inhibitors has been demonstrated to be important in beta cell growth. In this review, we consider and highlight some aspects of cell cycle regulation in relation to beta cell replication. The role of cell cycle regulation in beta cell replication is mostly from studies in rodent models, but whether...

  12. Single-cell sequencing in stem cell biology.

    Science.gov (United States)

    Wen, Lu; Tang, Fuchou

    2016-04-15

    Cell-to-cell variation and heterogeneity are fundamental and intrinsic characteristics of stem cell populations, but these differences are masked when bulk cells are used for omic analysis. Single-cell sequencing technologies serve as powerful tools to dissect cellular heterogeneity comprehensively and to identify distinct phenotypic cell types, even within a 'homogeneous' stem cell population. These technologies, including single-cell genome, epigenome, and transcriptome sequencing technologies, have been developing rapidly in recent years. The application of these methods to different types of stem cells, including pluripotent stem cells and tissue-specific stem cells, has led to exciting new findings in the stem cell field. In this review, we discuss the recent progress as well as future perspectives in the methodologies and applications of single-cell omic sequencing technologies.

  13. Wnt-Dependent Control of Cell Polarity in Cultured Cells.

    Science.gov (United States)

    Runkle, Kristin B; Witze, Eric S

    2016-01-01

    The secreted ligand Wnt5a regulates cell polarity and polarized cell movement during development by signaling through the poorly defined noncanonical Wnt pathway. Cell polarity regulates most aspects of cell behavior including the organization of apical/basolateral membrane domains of epithelial cells, polarized cell divisions along a directional plane, and front rear polarity during cell migration. These characteristics of cell polarity allow coordinated cell movements required for tissue formation and organogenesis during embryonic development. Genetic model organisms have been used to identify multiple signaling pathways including Wnt5a that are required to establish cell polarity and regulate polarized cell behavior. However, the downstream signaling events that regulate these complex cellular processes are still poorly understood. The methods below describe assays to study Wnt5a-induced cell polarity in cultured cells, which may facilitate our understanding of these complex signaling pathways.

  14. Molecular mechanisms controlling the cell cycle in embryonic stem cells.

    Science.gov (United States)

    Abdelalim, Essam M

    2013-12-01

    Embryonic stem (ES) cells are originated from the inner cell mass of a blastocyst stage embryo. They can proliferate indefinitely, maintain an undifferentiated state (self-renewal), and differentiate into any cell type (pluripotency). ES cells have an unusual cell cycle structure, consists mainly of S phase cells, a short G1 phase and absence of G1/S checkpoint. Cell division and cell cycle progression are controlled by mechanisms ensuring the accurate transmission of genetic information from generation to generation. Therefore, control of cell cycle is a complicated process, involving several signaling pathways. Although great progress has been made on the molecular mechanisms involved in the regulation of ES cell cycle, many regulatory mechanisms remain unknown. This review summarizes the current knowledge about the molecular mechanisms regulating the cell cycle of ES cells and describes the relationship existing between cell cycle progression and the self-renewal.

  15. Small cell glioblastoma or small cell carcinoma

    DEFF Research Database (Denmark)

    Hilbrandt, Christine; Sathyadas, Sathya; Dahlrot, Rikke H

    2013-01-01

    was admitted to the hospital with left-sided loss of motor function. A MRI revealed a 6 cm tumor in the right temporoparietal area. The histology was consistent with both glioblastoma multiforme (GBM) and small cell lung carcinoma (SCLC) but IHC was suggestive of a SCLC metastasis. PET-CT revealed...

  16. Dedifferentiated adipocyte-derived progeny cells (DFAT cells): Potential stem cells of adipose tissue.

    Science.gov (United States)

    Wei, Shengjuan; Zan, Linsen; Hausman, Gary J; Rasmussen, Theodore P; Bergen, Werner G; Dodson, Michael V

    2013-07-01

    Analyses of mature adipocytes have shown that they possess a reprogramming ability in vitro, which is associated with dedifferentiation. The subsequent dedifferentiated fat cells (DFAT cells) are multipotent and can differentiate into adipocytes and other cell types as well. Mature adipocytes can be easily obtained by biopsy, and the cloned progeny cells are homogeneous in vitro. Therefore, DFAT cells (a new type of stem cell) may provide an excellent source of cells for tissue regeneration, engineering and disease treatment. The dedifferentiation of mature adipocytes, the multipotent capacity of DFAT cells and comparisons and contrasts with mesenchymal stem cells (MSCs) and induced pluripotent stem cells (iPS) are discussed in this review.

  17. Biosensors for Cell Analysis.

    Science.gov (United States)

    Zhou, Qing; Son, Kyungjin; Liu, Ying; Revzin, Alexander

    2015-01-01

    Biosensors first appeared several decades ago to address the need for monitoring physiological parameters such as oxygen or glucose in biological fluids such as blood. More recently, a new wave of biosensors has emerged in order to provide more nuanced and granular information about the composition and function of living cells. Such biosensors exist at the confluence of technology and medicine and often strive to connect cell phenotype or function to physiological or pathophysiological processes. Our review aims to describe some of the key technological aspects of biosensors being developed for cell analysis. The technological aspects covered in our review include biorecognition elements used for biosensor construction, methods for integrating cells with biosensors, approaches to single-cell analysis, and the use of nanostructured biosensors for cell analysis. Our hope is that the spectrum of possibilities for cell analysis described in this review may pique the interest of biomedical scientists and engineers and may spur new collaborations in the area of using biosensors for cell analysis.

  18. MICROBIAL FUEL CELL

    DEFF Research Database (Denmark)

    2008-01-01

    A novel microbial fuel cell construction for the generation of electrical energy. The microbial fuel cell comprises: (i) an anode electrode, (ii) a cathode chamber, said cathode chamber comprising an in let through which an influent enters the cathode chamber, an outlet through which an effluent...

  19. Ghost cell odontogenic carcinoma.

    NARCIS (Netherlands)

    Nazaretian, S.P.; Schenberg, M.E.; Simpson, I.; Slootweg, P.J.

    2007-01-01

    Ghost cell odontogenic carcinoma (GCOC) is the malignant counterpart of calcifying cystic odontogenic tumour and dentinogenic ghost cell tumour. This is the case of a middle-aged male who presented with a slow-growing maxillary tumour. He was asymptomatic until pain symptoms developed prior to initi

  20. Electrochemical cell stack assembly

    Science.gov (United States)

    Jacobson, Craig P.; Visco, Steven J.; De Jonghe, Lutgard C.

    2010-06-22

    Multiple stacks of tubular electrochemical cells having a dense electrolyte disposed between an anode and a cathode preferably deposited as thin films arranged in parallel on stamped conductive interconnect sheets or ferrules. The stack allows one or more electrochemical cell to malfunction without disabling the entire stack. Stack efficiency is enhanced through simplified gas manifolding, gas recycling, reduced operating temperature and improved heat distribution.

  1. Ghrelin and cell differentiation

    Institute of Scientific and Technical Information of China (English)

    Geyang Xu; Yin Li; Wenjiao An; Weizhen Zhang

    2008-01-01

    Ghrelin, an endogenous ligand for the growth hormone secretagogue receptor, is a gastric hormone that has been found to have a wide variety of biological functions. This review summarizes our current understanding of the effects of ghrelin on cell differentiation and tissue development, with an emphasis on the lineage determination of mesenchymal stem cells.

  2. Cell Phones for Education

    Science.gov (United States)

    Roberson, James H.; Hagevik, Rita A.

    2008-01-01

    Cell phones are fast becoming an integral part of students' everyday lives. They are regarded as important companions and tools for personal expression. School-age children are integrating the cell phone as such, and thus placing a high value on them. Educators endeavor to instill in students a high value for education, but often meet with…

  3. PLATINUM AND FUEL CELLS

    Science.gov (United States)

    Platinum requirements for fuel cell vehicles (FCVS) have been identified as a concern and possible problem with FCV market penetration. Platinum is a necessary component of the electrodes of fuel cell engines that power the vehicles. The platinum is deposited on porous electrodes...

  4. Modeling: driving fuel cells

    Directory of Open Access Journals (Sweden)

    Michael Francis

    2002-05-01

    Fuel cells were invented in 1839 by Sir William Grove, a Welsh judge and gentleman scientist, as a result of his experiments on the electrolysis of water. To put it simply, fuel cells are electrochemical devices that take hydrogen gas from fuel, combine it with oxygen from the air, and generate electricity and heat, with water as the only by-product.

  5. The Constitution by Cell

    Science.gov (United States)

    Greenhut, Stephanie; Jones, Megan

    2010-01-01

    On their visit to the National Archives Experience in Washington, D.C., students in Jenni Ashley and Gay Brock's U.S. history classes at the Potomac School in McLean, Virginia, participated in a pilot program called "The Constitution by Cell." Armed with their cell phones, a basic understanding of the Constitution, and a willingness to participate…

  6. Programmed cell death

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    The purpose of this conference to provide a multidisciplinary forum for exchange of state-of-the-art information on the role programmed cell death plays in normal development and homeostasis of many organisms. This volume contains abstracts of papers in the following areas: invertebrate development; immunology/neurology; bcl-2 family; biochemistry; programmed cell death in viruses; oncogenesis; vertebrate development; and diseases.

  7. Fuel cells: Operating flexibly

    Science.gov (United States)

    Lee, Young Moo

    2016-09-01

    Fuel cells typically function well only in rather limited temperature and humidity ranges. Now, a proton exchange membrane consisting of ion pair complexes is shown to enable improved fuel cell performance under a wide range of conditions that are unattainable with conventional approaches.

  8. Tetraspanins in Mast Cells

    Directory of Open Access Journals (Sweden)

    Martin eKöberle

    2012-05-01

    Full Text Available Mast cells are key mediators of the immune system, most prominently known for their role in eliciting harmful allergic reactions. Mast cell mediator release (e. g. by degranulation is triggered by Fc{epsilon}RI recognition of antigen – IgE complexes. Until today no therapeutic targeting of this and other mast cell activation pathways is established. Among possible new candidates there are tetraspanins that have been described on mast cells already several years ago.Tetraspanins are transmembrane proteins acting as scaffolds, mediating local clustering of their interaction partners and thus amplify their activities. More recently, tetraspanins were also found to exert intrinsic receptor functions. Tetraspanins have been found to be crucial components of fundamental biological processes like cell motility and adhesion. In immune cells, they not only boost the effectiveness of antigen presentation by clustering MHC molecules, they are also key players in all kinds of degranulation events and immune receptor clustering. This review focuses on the contribution of tetraspanins clustered with Fc{epsilon}RI or residing in granule membranes to classical mast cells functions but also undertakes an outlook on the possible contribution of tetraspanins to newly described mast cell functions and discusses possible drugging strategies.

  9. Tumor cell metabolism

    Science.gov (United States)

    Romero-Garcia, Susana; Lopez-Gonzalez, Jose Sullivan; B´ez-Viveros, José Luis; Aguilar-Cazares, Dolores

    2011-01-01

    Cancer is a genetic disease that is caused by mutations in oncogenes, tumor suppressor genes and stability genes. The fact that the metabolism of tumor cells is altered has been known for many years. However, the mechanisms and consequences of metabolic reprogramming have just begun to be understood. In this review, an integral view of tumor cell metabolism is presented, showing how metabolic pathways are reprogrammed to satisfy tumor cell proliferation and survival requirements. In tumor cells, glycolysis is strongly enhanced to fulfill the high ATP demands of these cells; glucose carbons are the main building blocks in fatty acid and nucleotide biosynthesis. Glutaminolysis is also increased to satisfy NADPH regeneration, whereas glutamine carbons replenish the Krebs cycle, which produces metabolites that are constantly used for macromolecular biosynthesis. A characteristic feature of the tumor microenvironment is acidosis, which results from the local increase in lactic acid production by tumor cells. This phenomenon is attributed to the carbons from glutamine and glucose, which are also used for lactic acid production. Lactic acidosis also directs the metabolic reprogramming of tumor cells and serves as an additional selective pressure. Finally, we also discuss the role of mitochondria in supporting tumor cell metabolism. PMID:22057267

  10. Mesangial cell biology

    Energy Technology Data Exchange (ETDEWEB)

    Abboud, Hanna E., E-mail: Abboud@uthscsa.edu

    2012-05-15

    Mesangial cells originate from the metanephric mesenchyme and maintain structural integrity of the glomerular microvascular bed and mesangial matrix homeostasis. In response to metabolic, immunologic or hemodynamic injury, these cells undergo apoptosis or acquire an activated phenotype and undergo hypertrophy, proliferation with excessive production of matrix proteins, growth factors, chemokines and cytokines. These soluble factors exert autocrine and paracrine effects on the cells or on other glomerular cells, respectively. MCs are primary targets of immune-mediated glomerular diseases such as IGA nephropathy or metabolic diseases such as diabetes. MCs may also respond to injury that primarily involves podocytes and endothelial cells or to structural and genetic abnormalities of the glomerular basement membrane. Signal transduction and oxidant stress pathways are activated in MCs and likely represent integrated input from multiple mediators. Such responses are convenient targets for therapeutic intervention. Studies in cultured MCs should be supplemented with in vivo studies as well as examination of freshly isolated cells from normal and diseases glomeruli. In addition to ex vivo morphologic studies in kidney cortex, cells should be studied in their natural environment, isolated glomeruli or even tissue slices. Identification of a specific marker of MCs should help genetic manipulation as well as selective therapeutic targeting of these cells. Identification of biological responses of MCs that are not mediated by the renin–angiotensin system should help development of novel and effective therapeutic strategies to treat diseases characterized by MC pathology.

  11. Stem cells in dermatology.

    Science.gov (United States)

    Ogliari, Karolyn Sassi; Marinowic, Daniel; Brum, Dario Eduardo; Loth, Fabrizio

    2014-01-01

    Preclinical and clinical research have shown that stem cell therapy could be a promising therapeutic option for many diseases in which current medical treatments do not achieve satisfying results or cure. This article describes stem cells sources and their therapeutic applications in dermatology today.

  12. [Acute plasma cell leukemia].

    Science.gov (United States)

    Monsalbe, V; Domíngues, C; Roa, I; Busel, D; González, S

    1989-01-01

    Plasma Cell Leukemia is a very rare form of plasmocytic dyscrasia, whose clinical and pathological characteristics warrant its recognition as a distinct subentity. We report the case of a 60 years old man who presented a rapidly fatal acute plasma cell leukemia, with multiple osteolytic lesions, hipercalcemia, renal and cardiac failure.

  13. T-cell costimulation

    DEFF Research Database (Denmark)

    Owens, T

    1996-01-01

    The CD40L molecule expressed by CD4+ regulatory T lymphocytes is known to deliver signals that activate B cells and macrophages. It now appears that CD40L regulates T cells themselves, during both their development and their participation in adaptive immune responses....

  14. "Angular" plasma cell cheilitis.

    Science.gov (United States)

    da Cunha Filho, Roberto Rheingantz; Tochetto, Lucas Baldissera; Tochetto, Bruno Baldissera; de Almeida, Hiram Larangeira; Lorencette, Nádia Aparecida; Netto, José Fillus

    2014-03-17

    Plasma cell cheilitis is an extremely rare disease, characterized by erythematous-violaceous, ulcerated and asymptomatic plaques, which evolve slowly. The histological characteristics include dermal infiltrate composed of mature plasmocytes. We report a case of Plasma cell angular cheilitis in a 58-year-old male, localized in the lateral oral commissure.

  15. "Angular" plasma cell cheilitis

    OpenAIRE

    da Cunha Filho, Roberto Rheingantz; Tochetto, Lucas Baldissera; Tochetto, Bruno Baldissera; de Almeida Jr, Hiram Larangeira; Lorencette, Nadia Aparecida; Netto, Jose Fillus

    2014-01-01

    Plasma cell cheilitis is an extremely rare disease, characterized by erythematous-violaceous, ulcerated and asymptomatic plaques, which evolve slowly. The histological characteristics include dermal infiltrate composed of mature plasmocytes. We report a case of Plasma cell angular cheilitis in a 58-year-old male, localized in the lateral oral commissure.

  16. NCAM regulates cell motility.

    Science.gov (United States)

    Prag, Søren; Lepekhin, Eugene A; Kolkova, Kateryna; Hartmann-Petersen, Rasmus; Kawa, Anna; Walmod, Peter S; Belman, Vadym; Gallagher, Helen C; Berezin, Vladimir; Bock, Elisabeth; Pedersen, Nina

    2002-01-15

    Cell migration is required during development of the nervous system. The regulatory mechanisms for this process, however, are poorly elucidated. We show here that expression of or exposure to the neural cell adhesion molecule (NCAM) strongly affected the motile behaviour of glioma cells independently of homophilic NCAM interactions. Expression of the transmembrane 140 kDa isoform of NCAM (NCAM-140) caused a significant reduction in cellular motility, probably through interference with factors regulating cellular attachment, as NCAM-140-expressing cells exhibited a decreased attachment to a fibronectin substratum compared with NCAM-negative cells. Ectopic expression of the cytoplasmic part of NCAM-140 also inhibited cell motility, presumably via the non-receptor tyrosine kinase p59(fyn) with which NCAM-140 interacts. Furthermore, we showed that the extracellular part of NCAM acted as a paracrine inhibitor of NCAM-negative cell locomotion through a heterophilic interaction with a cell-surface receptor. As we showed that the two N-terminal immunoglobulin modules of NCAM, which are known to bind to heparin, were responsible for this inhibition, we presume that this receptor is a heparan sulfate proteoglycan. A model for the inhibitory effect of NCAM is proposed, which involves competition between NCAM and extracellular components for the binding to membrane-associated heparan sulfate proteoglycan.

  17. The Constitution by Cell

    Science.gov (United States)

    Greenhut, Stephanie; Jones, Megan

    2010-01-01

    On their visit to the National Archives Experience in Washington, D.C., students in Jenni Ashley and Gay Brock's U.S. history classes at the Potomac School in McLean, Virginia, participated in a pilot program called "The Constitution by Cell." Armed with their cell phones, a basic understanding of the Constitution, and a willingness to…

  18. Retinal stem cells and potential cell transplantation treatments.

    Science.gov (United States)

    Lin, Tai-Chi; Hsu, Chih-Chien; Chien, Ke-Hung; Hung, Kuo-Hsuan; Peng, Chi-Hsien; Chen, Shih-Jen

    2014-11-01

    The retina, histologically composed of ten delicate layers, is responsible for light perception and relaying electrochemical signals to the secondary neurons and visual cortex. Retinal disease is one of the leading clinical causes of severe vision loss, including age-related macular degeneration, Stargardt's disease, and retinitis pigmentosa. As a result of the discovery of various somatic stem cells, advances in exploring the identities of embryonic stem cells, and the development of induced pluripotent stem cells, cell transplantation treatment for retinal diseases is currently attracting much attention. The sources of stem cells for retinal regeneration include endogenous retinal stem cells (e.g., neuronal stem cells, Müller cells, and retinal stem cells from the ciliary marginal zone) and exogenous stem cells (e.g., bone mesenchymal stem cells, adipose-derived stem cells, embryonic stem cells, and induced pluripotent stem cells). The success of cell transplantation treatment depends mainly on the cell source, the timing of cell harvesting, the protocol of cell induction/transplantation, and the microenvironment of the recipient's retina. This review summarizes the different sources of stem cells for regeneration treatment in retinal diseases and surveys the more recent achievements in animal studies and clinical trials. Future directions and challenges in stem cell transplantation are also discussed.

  19. Transition of mesenchymal stem/stromal cells to endothelial cells

    NARCIS (Netherlands)

    M. Crisan (Mihaela)

    2013-01-01

    textabstractMesenchymal stem/stromal cells (MSCs) are heterogeneous. A fraction of these cells constitute multipotent cells that can self-renew and mainly give rise to mesodermal lineage cells such as adipocytes, osteocytes and chondrocytes. The ability of MSCs to differentiate into endothelial cell

  20. Induction of embryonic stem cells to hematopoietic cells in vitro

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    In order to get hematopoietic cells from embryonic stem (ES) cells and to study development mechanisms of hematopoietic cells, the method of inducing embryonic stem cells to hematopoietic cells was explored by differenciating mouse ES cells and human embryonic cells in three stages. The differentiated cells were identified by flow cytometry, immunohistochemistry and Wright's staining. The results showed that embryoid bodies (EBs) could form when ES cells were cultured in the medium with 2-mercaptoethanol (2-ME). However, cytokines, such as stem cell factor (SCF), thrombopoietin (TPO), interleukin-3 (IL-3), interleukin-6 (IL-6), erythropoietin (EPO) and granular colony stimulating factor (G-CSF), were not helpful for forming EBs. SCF, TPO and embryonic cell conditional medium were useful for the differentiation of mouse EBs to hematopoietic progenitors. Eighty-six percent of these cells were CD34+ after 6-d culture. Hematopoietic progenitors differentiated to B lymphocytes when they were cocultured with primary bone marrow stroma cells in the DMEM medium with SCF and IL-6. 14 d later, most of the cells were CD34-CD38+. Wright's staining and immunohistochemistry showed that 80% of these cells were plasma-like morphologically and immunoglubolin positive. The study of hematopoietic cells from human embryonic cells showed that human embryonic cell differentiation was very similar to that of mouse ES cells. They could form EBs in the first stage and the CD34 positive cells account for about 48.5% in the second stage.

  1. 含人 LINGO -1慢病毒干扰载体的构建与鉴定%Construction and Identification of Lentiviral Interference Vector That Including Human LINGO-1

    Institute of Scientific and Technical Information of China (English)

    索磊; 杨印祥; 栾佐

    2016-01-01

    Objective To construct the lentiviral interference vector that including human LINGO - 1 in vitro and evaluate its interference effects on the target gene LINGO - 1. Methods From March to November in 2015,interference sequences that targeted at human LINGO - 1 interfered by short hairpin RNA(LINGO - 1 shRNA)were designed and synthesized according to the LINGO - 1 gene sequence reported in GenBank database,LINGO - 1 shRNA was cloned into recombinant plasmid vectors. They were assembled in 293T cells after sequence verification. The test divided into interference vector group of target gene(experimental group)and interference vector group of mismatch sequence(control group),the lentiviral vectors were transfected into U251 cells of human glioma, and its efficiency of infection was observed by fluorescence microscopy. Immunofluorescent staining and real - time fluorescent quantitative polymerase chain reaction(qPCR)method were adopted to detect the expression level of LINGO - 1 mRNA. The expression level of LINGO - 1 was detected by Western blotting method. Results Two groups of lentiviral interference vectors were successfully constructed,and the virus stock solutions with a titer of 2 × 108 TU/ ml and 4 × 108 TU/ ml were obtained respectively after package. After U251 cells of human glioma were transfected with virus vectors,the transfection efficiency of vectors in experimental group and control group were 96. 6% and 95. 2% respectively. Immunofluorescent staining presented that LINGO - 1 was highly expressed in U251 cells of human glioma, and immunofluorescence in experimental group weakened after the transfection of lentiviral vectors. The expression level of LINGO- 1 mRNA in experimental group(0. 09 ± 0. 01)was significantly decreased compared with that in control group(1. 00 ± 0. 00) (t = 12. 87,P ﹤ 0. 01),and the interference rate of LINGO - 1 mRNA relative expression in experimental group was 91. 0% . Compared with control group(1. 00 ± 0. 00),the

  2. Solid electrolytic fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Sakai, Masayasu; Yamauchi, Yasuhiro; Kamisaka, Mitsuo; Notomi, Kei.

    1989-04-21

    Concerning a solid electrolytic fuel cell with a gas permeable substrate pipe, a fuel electrode installed on this substrate pipe and an air electrode which is laminated on this fuel electrode with the electrolyte in between, the existing fuel cell of this kind uses crystals of CaMnO3, etc. for the material of the air electrode, but its electric resistance is big and in order to avert this, it is necessary to make the film thickness of the air electrode big. However, in such a case, the entry of the air into its inside worsens and the cell performance cannot develop satisfactorily. In view of the above, in order to obtain a high performance solid electrolytic fuel cell which can improve electric conductivity without damaging diffusion rate of the air, this invention proposes with regard to the aforementioned solid electrolytic fuel cell to install a heat resistant and conductive member inside the above air electrode. 6 figs.

  3. HTPEM Fuel Cell Impedance

    DEFF Research Database (Denmark)

    Vang, Jakob Rabjerg

    As part of the process to create a fossil free Denmark by 2050, there is a need for the development of new energy technologies with higher efficiencies than the current technologies. Fuel cells, that can generate electricity at higher efficiencies than conventional combustion engines, can...... potentially play an important role in the energy system of the future. One of the fuel cell technologies, that receives much attention from the Danish scientific community is high temperature proton exchange membrane (HTPEM) fuel cells based on polybenzimidazole (PBI) with phosphoric acid as proton conductor....... This type of fuel cell operates at higher temperature than comparable fuel cell types and they distinguish themselves by high CO tolerance. Platinum based catalysts have their efficiency reduced by CO and the effect is more pronounced at low temperature. This Ph.D. Thesis investigates this type of fuel...

  4. Cell fusions in mammals

    DEFF Research Database (Denmark)

    Larsson, Lars-Inge; Bjerregaard, Bolette; Talts, Jan Fredrik

    2008-01-01

    Cell fusions are important to fertilization, placentation, development of skeletal muscle and bone, calcium homeostasis and the immune defense system. Additionally, cell fusions participate in tissue repair and may be important to cancer development and progression. A large number of factors appear...... to regulate cell fusions, including receptors and ligands, membrane domain organizing proteins, proteases, signaling molecules and fusogenic proteins forming alpha-helical bundles that bring membranes close together. The syncytin family of proteins represent true fusogens and the founding member, syncytin-1......, has been documented to be involved in fusions between placental trophoblasts, between cancer cells and between cancer cells and host ells. We review the literature with emphasis on the syncytin family and propose that syncytins may represent universal fusogens in primates and rodents, which work...

  5. Cell Control Engineering

    DEFF Research Database (Denmark)

    Lynggaard, Hans Jørgen Birk; Alting, Leo

    1996-01-01

    The engineering process of creating cell control systems is described, and a Cell Control Engineering (CCE) concept is defined. The purpose is to assist people, representing different disciplines in the organisation, to implement cell controllers by addressing the complexity of having many systems...... in physically and logically different and changing manufacturing environments. The defined CCE concept combines state-of-the-art of commercially available enabling technologies for automation system software development, generic cell control models and guidelines for the complete engineering process....... It facilitates the understanding of the task and structure of cell controllers and uses this knowledge directly in the implementation of the system. By applying generic models CCE facilitates reuse of software components and maintenance of applications. In many enterprises, software makes up an increasing part...

  6. Toward sustainable fuel cells

    DEFF Research Database (Denmark)

    Stephens, Ifan; Rossmeisl, Jan; Chorkendorff, Ib

    2016-01-01

    A quarter of humanity's current energy consumption is used for transportation (1). Low-temperature hydrogen fuel cells offer much promise for replacing this colossal use of fossil fuels with renewables; these fuel cells produce negligible emissions and have a mileage and filling time equal...... to a regular gasoline car. However, current fuel cells require 0.25 g of platinum (Pt) per kilowatt of power (2) as catalysts to drive the electrode reactions. If the entire global annual production of Pt were devoted to fuel cell vehicles, fewer than 10 million vehicles could be produced each year, a mere 10......% of the annual automotive vehicle production. Lowering the Pt loading in a fuel cell to a sustainable level requires the reactivity of Pt to be tuned so that it accelerates oxygen reduction more effectively (3). Two reports in this issue address this challenge (4, 5)....

  7. Storing Blood Cells

    Science.gov (United States)

    1976-01-01

    The National Cancer Institute worked with Goddard Space Flight Center to propose a solution to the blood-cell freezing problem. White blood cells and bone marrow are stored for future use by leukemia patients as a result of Goddard and Jet Propulsion Laboratory expertise in electronics and cryogenics. White blood cell and bone marrow bank established using freezing unit. Freezing unit monitors temperature of cells themselves. Thermocouple placed against polyethylene container relays temperature signals to an electronic system which controls small heaters located outside container. Heaters allow liquid nitrogen to circulate at constant temperature and maintain consistent freezing rate. Ability to freeze, store, and thaw white cells and bone marrow without damage is important in leukemia treatment.

  8. Mast cell leukemia.

    Science.gov (United States)

    Georgin-Lavialle, Sophie; Lhermitte, Ludovic; Dubreuil, Patrice; Chandesris, Marie-Olivia; Hermine, Olivier; Damaj, Gandhi

    2013-02-21

    Mast cell leukemia (MCL) is a very rare form of aggressive systemic mastocytosis accounting for mast cell activation-involvement of the liver, spleen, peritoneum, bones, and marrow-are frequent. Diagnosis is based on the presence of ≥ 20% atypical mast cells in the marrow or ≥ 10% in the blood; however, an aleukemic variant is frequently encountered in which the number of circulating mast cells is < 10%. The common phenotypic features of pathologic mast cells encountered in most forms of mastocytosis are unreliable in MCL. Unexpectedly, non-KIT D816V mutations are frequent and therefore, complete gene sequencing is necessary. Therapy usually fails and the median survival time is < 6 months. The role of combination therapies and bone marrow transplantation needs further investigation.

  9. Dynamics of cell orientation

    Science.gov (United States)

    de, Rumi; Zemel, Assaf; Safran, Samuel A.

    2007-09-01

    Many physiological processes depend on the response of biological cells to mechanical forces generated by the contractile activity of the cell or by external stresses. Using a simple theoretical model that includes the forces due to both the mechanosensitivity of cells and the elasticity of the matrix, we predict the dynamics and orientation of cells in both the absence and presence of applied stresses. The model predicts many features observed in measurements of cellular forces and orientation including the increase with time of the cellular forces in the absence of applied stress and the consequent decrease of the force in the presence of quasi-static stresses. We also explain the puzzling observation of parallel alignment of cells for static and quasi-static stresses and of nearly perpendicular alignment for dynamically varying stresses. In addition, we predict the response of the cellular orientation to a sinusoidally varying applied stress as a function of frequency.

  10. Physics of adherent cells

    Science.gov (United States)

    Schwarz, Ulrich S.; Safran, Samuel A.

    2013-07-01

    One of the most unique physical features of cell adhesion to external surfaces is the active generation of mechanical force at the cell-material interface. This includes pulling forces generated by contractile polymer bundles and networks, and pushing forces generated by the polymerization of polymer networks. These forces are transmitted to the substrate mainly by focal adhesions, which are large, yet highly dynamic adhesion clusters. Tissue cells use these forces to sense the physical properties of their environment and to communicate with each other. The effect of forces is intricately linked to the material properties of cells and their physical environment. Here a review is given of recent progress in our understanding of the role of forces in cell adhesion from the viewpoint of theoretical soft matter physics and in close relation to the relevant experiments.

  11. Metallization of bacteria cells

    Institute of Scientific and Technical Information of China (English)

    黎向锋; 李雅芹; 蔡军; 张德远

    2003-01-01

    Bacteria cells with different standard shapes are well suited for use as templates for the fabrication of magnetic and electrically conductive microstructures. In this paper, metallization of bacteria cells is demonstrated by an electroless deposition technique of nickel-phosphorus initiated by colloid palladium-tin catalyst on the surfaces of Citeromyces matritensis and Bacillus cereus. The activated and metallized bacteria cells have been characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction analysis (XRD). Results showed that both Citeromyces matritensis and Bacillus cereus had no deformation in shape after metallization; the metallized films deposited on the surfaces of bacteria cells are homogeneous in thickness and noncrystalline in phase structure. The kinetics of colloid palladium-tin solution and electroless plating on bacteria cells is discussed.

  12. Mast cells and inflammation.

    Science.gov (United States)

    Frenzel, Laurent; Hermine, Olivier

    2013-03-01

    The prominent role for mast cells in the inflammatory response has been increasingly well documented in recent years. Mast cells not only contribute to maintain homeostasis via degranulation and to generate IgE-mediated allergic reactions, but also sit at a major crossroads for both innate and adaptive immune responses. The part played by mast cells in chronic inflammatory diseases such as rheumatoid arthritis and multiple sclerosis identifies mast cells as a valuable treatment target in these diseases. Tyrosine-kinase inhibitors targeting the c-Kit mast cell receptor have been found effective in treating rheumatoid arthritis, asthma, and multiple sclerosis. When used in combination with other available drugs, tyrosine-kinase inhibitors may improve the therapeutic management of these diseases.

  13. Cell Radiation Experiment System

    Science.gov (United States)

    Morrison, Dennis R.

    2010-01-01

    The cell radiation experiment system (CRES) is a perfused-cell culture apparatus, within which cells from humans or other animals can (1) be maintained in homeostasis while (2) being exposed to ionizing radiation during controlled intervals and (3) being monitored to determine the effects of radiation and the repair of radiation damage. The CRES can be used, for example, to determine effects of drug, radiation, and combined drug and radiation treatments on both normal and tumor cells. The CRES can also be used to analyze the effects of radiosensitive or radioprotectant drugs on cells subjected to radiation. The knowledge gained by use of the CRES is expected to contribute to the development of better cancer treatments and of better protection for astronauts, medical-equipment operators, and nuclear-power-plant workers, and others exposed frequently to ionizing radiation.

  14. Solar cell radiation handbook

    Science.gov (United States)

    Tada, H. Y.; Carter, J. R., Jr.; Anspaugh, B. E.; Downing, R. G.

    1982-01-01

    The handbook to predict the degradation of solar cell electrical performance in any given space radiation environment is presented. Solar cell theory, cell manufacturing and how they are modeled mathematically are described. The interaction of energetic charged particles radiation with solar cells is discussed and the concept of 1 MeV equivalent electron fluence is introduced. The space radiation environment is described and methods of calculating equivalent fluences for the space environment are developed. A computer program was written to perform the equivalent fluence calculations and a FORTRAN listing of the program is included. Data detailing the degradation of solar cell electrical parameters as a function of 1 MeV electron fluence are presented.

  15. Cell cycle regulation in human embryonic stem cells: links to adaptation to cell culture.

    Science.gov (United States)

    Barta, Tomas; Dolezalova, Dasa; Holubcova, Zuzana; Hampl, Ales

    2013-03-01

    Cell cycle represents not only a tightly orchestrated mechanism of cell replication and cell division but it also plays an important role in regulation of cell fate decision. Particularly in the context of pluripotent stem cells or multipotent progenitor cells, regulation of cell fate decision is of paramount importance. It has been shown that human embryonic stem cells (hESCs) show unique cell cycle characteristics, such as short doubling time due to abbreviated G1 phase; these properties change with the onset of differentiation. This review summarizes the current understanding of cell cycle regulation in hESCs. We discuss cell cycle properties as well as regulatory machinery governing cell cycle progression of undifferentiated hESCs. Additionally, we provide evidence that long-term culture of hESCs is accompanied by changes in cell cycle properties as well as configuration of several cell cycle regulatory molecules.

  16. Advances in stem cell research

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@In 1998, biologists Thomson and Gearhart successfully derived stem cells from human embryos. One year later, several researchers discovered that adult stem cells still retain the ability to be differentiated into unrelated types of cells. Advances in stem cell research open a promising direction for applied medical science. Moreover, it may also force scientists to reconsider the fundamental theory about how cells grow up. Stem cell research was considered by Science as the top of the ten breakthroughs of science of the year[1]. This paper gives a survey of recent advances in stem cell research. 1 Overview In the 1980s, embryonic stem cell and/or embryonic germ cell line (ES cell line, EG cell line) of multifarious mammalian animals, especially those of non-human pri-mates, had been established. In 1998, Thomson and Shamblott obtained ES, EG cell lines from human blasto-cysts and gonad ridges of early human embryos, respec-tively. Their research brought up an ethical debate about whether human embryos can be used as experimental materials. It was not appeased until 1999 when research-ers discovered that stem cells from adults still retain the ability to become different kinds of tissue cells. For in-stance, brain cells can become blood cells[2], and cells from bone marrow can become cells in liver. Scientists believe, for a long time, that cells can only be developed from early pluripotent embryo cells; the differentiation potential of stem cells from mature tissues is restricted to only one of the cell types of the tissue where stem cells are obtained. Recent stem cell researches, however, sub-verted the traditional view of stem cells. These discoveries made scientists speed ahead with the work on adult stem cells, hoping to discover whether their promise will rival that of ES cells.

  17. CCL22-specific T Cells

    DEFF Research Database (Denmark)

    Martinenaite, Evelina; Munir Ahmad, Shamaila; Hansen, Morten

    2016-01-01

    Tumor cells and tumor-infiltrating macrophages produce the chemokine CCL22, which attracts regulatory T cells (Tregs) into the tumor microenvironment, decreasing anticancer immunity. Here, we investigated the possibility of targeting CCL22-expressing cells by activating specific T cells. We...... analyzed the CCL22 protein signal sequence, identifying a human leukocyte antigen A2- (HLA-A2-) restricted peptide epitope, which we then used to stimulate peripheral blood mononuclear cells (PMBCs) to expand populations of CCL22-specific T cells in vitro. T cells recognizing an epitope derived from...... the signal-peptide of CCL22 will recognize CCL22-expressing cells even though CCL22 is secreted out of the cell. CCL22-specific T cells recognized and killed CCL22-expressing cancer cells. Furthermore, CCL22-specific T cells lysed acute monocytic leukemia cells in a CCL22 expression-dependent manner. Using...

  18. From Adult Bone Marrow Cells to Other Cell Lineages:Transdifferentiation or Cells Fusion

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Recent studies have demonstrated that intravenous transplantation or local injection of bone marrow cells can induce unexpected changes of their fate. The results of these experiments showed that after transplantation or injecton, some of tissue specific somatic cells such as hepatocytes, skeleton, cardiac muscle cells and brain cells expressed the donor cell-specific genes, such as Y chromosome. There are two hypotheses that can explain this phenomenon. One is bone marrow stem cell transdifferentiation and the other is spontaneous cell fusion.

  19. Oscillating Cell Culture Bioreactor

    Science.gov (United States)

    Freed, Lisa E.; Cheng, Mingyu; Moretti, Matteo G.

    2010-01-01

    To better exploit the principles of gas transport and mass transport during the processes of cell seeding of 3D scaffolds and in vitro culture of 3D tissue engineered constructs, the oscillatory cell culture bioreactor provides a flow of cell suspensions and culture media directly through a porous 3D scaffold (during cell seeding) and a 3D construct (during subsequent cultivation) within a highly gas-permeable closed-loop tube. This design is simple, modular, and flexible, and its component parts are easy to assemble and operate, and are inexpensive. Chamber volume can be very low, but can be easily scaled up. This innovation is well suited to work with different biological specimens, particularly with cells having high oxygen requirements and/or shear sensitivity, and different scaffold structures and dimensions. The closed-loop changer is highly gas permeable to allow efficient gas exchange during the cell seeding/culturing process. A porous scaffold, which may be seeded with cells, is fixed by means of a scaffold holder to the chamber wall with scaffold/construct orientation with respect to the chamber determined by the geometry of the scaffold holder. A fluid, with/without biological specimens, is added to the chamber such that all, or most, of the air is displaced (i.e., with or without an enclosed air bubble). Motion is applied to the chamber within a controlled environment (e.g., oscillatory motion within a humidified 37 C incubator). Movement of the chamber induces relative motion of the scaffold/construct with respect to the fluid. In case the fluid is a cell suspension, cells will come into contact with the scaffold and eventually adhere to it. Alternatively, cells can be seeded on scaffolds by gel entrapment prior to bioreactor cultivation. Subsequently, the oscillatory cell culture bioreactor will provide efficient gas exchange (i.e., of oxygen and carbon dioxide, as required for viability of metabolically active cells) and controlled levels of fluid

  20. Many facets of stem cells

    Institute of Scientific and Technical Information of China (English)

    Jiarui Wu

    2011-01-01

    @@ Research area on stem cells is one of frontiers in biology.The collection of five research articles in this issue aims to cover timely developments in stem cell biology, ranging from generating and identifying stem cell line to manipulating stem cells, and from basic mechanism analysis to applied medical potential.These papers reflect the various research tasks in stem cell biology.

  1. Microfluidics for single cell analysis

    DEFF Research Database (Denmark)

    Jensen, Marie Pødenphant

    Isolation and manipulation of single cells have gained an increasing interest from researchers because of the heterogeneity of cells from the same cell culture. Single cell analysis can ensure a better understanding of differences between individual cells and potentially solve a variety of clinic...

  2. Low White Blood Cell Count

    Science.gov (United States)

    Symptoms Low white blood cell count By Mayo Clinic Staff A low white blood cell count (leukopenia) is a decrease in disease-fighting cells ( ... a decrease in a certain type of white blood cell (neutrophil). The definition of low white blood cell ...

  3. CellNet: network biology applied to stem cell engineering.

    Science.gov (United States)

    Cahan, Patrick; Li, Hu; Morris, Samantha A; Lummertz da Rocha, Edroaldo; Daley, George Q; Collins, James J

    2014-08-14

    Somatic cell reprogramming, directed differentiation of pluripotent stem cells, and direct conversions between differentiated cell lineages represent powerful approaches to engineer cells for research and regenerative medicine. We have developed CellNet, a network biology platform that more accurately assesses the fidelity of cellular engineering than existing methodologies and generates hypotheses for improving cell derivations. Analyzing expression data from 56 published reports, we found that cells derived via directed differentiation more closely resemble their in vivo counterparts than products of direct conversion, as reflected by the establishment of target cell-type gene regulatory networks (GRNs). Furthermore, we discovered that directly converted cells fail to adequately silence expression programs of the starting population and that the establishment of unintended GRNs is common to virtually every cellular engineering paradigm. CellNet provides a platform for quantifying how closely engineered cell populations resemble their target cell type and a rational strategy to guide enhanced cellular engineering.

  4. Embryonic stem cells: testing the germ-cell theory.

    Science.gov (United States)

    Hochedlinger, Konrad

    2011-10-25

    The exact cellular origin of embryonic stem cells remains elusive. Now a new study provides compelling evidence that embryonic stem cells, established under conventional culture conditions, originate from a transient germ-cell state.

  5. Mesenchymal stem cells: cell biology and potential use in therapy

    DEFF Research Database (Denmark)

    Kassem, Moustapha; Kristiansen, Malthe; Abdallah, Basem M

    2004-01-01

    Mesenchymal stem cells are clonogenic, non-haematopoietic stem cells present in the bone marrow and are able to differentiate into multiple mesoderm-type cell lineages e.g. osteoblasts, chondrocytes, endothelial-cells and also non-mesoderm-type lineages e.g. neuronal-like cells. Several methods...... are currently available for isolation of the mesenchymal stem cells based on their physical and immunological characteristics. Because of the ease of their isolation and their extensive differentiation potential, mesenchymal stem cells are among the first stem cell types to be introduced in the clinic. Recent...... studies have demonstrated that the life span of mesenchymal stem cells in vitro can be extended by increasing the levels of telomerase expression in the cells and thus allowing culture of large number of cells needed for therapy. In addition, it has been shown that it is possible to culture the cells...

  6. Immunology of Stem Cells and Cancer Stem Cells

    Institute of Scientific and Technical Information of China (English)

    Xiao-Feng Yang

    2007-01-01

    The capacity of pluri-potent stem cells to repair the tissues in which stem cells reside holds great promise in development of novel cell replacement therapeutics for treating chronic and degenerative diseases. However,numerous reports show that stem cell therapy, even in an autologous setting, triggers lymphocyte infiltration and inflammation. Therefore, an important question to be answered is how the host immune system responds to engrafted autologous stem cells or allogeneous stem cells. In this brief review, we summarize the progress in several related areas in this field, including some of our data, in four sections: (1) immunogenicity of stem cells; (2)strategies to inhibit immune rejection to allograft stem cells; (3) immune responses to cancer stem cells; and (4)mesenchymal stem cells in immune regulation. Improvement of our understanding on these and other aspects of immune system-stem cell interplay would greatly facilitate the development of stem cell-based therapeutics for regenerative purposes.

  7. Cell density monitoring and control of microencapsulated CHO cell cultures

    OpenAIRE

    Cole, Harriet Emma

    2015-01-01

    Though mammalian cells play a key role in the manufacturing of recombinant glycosylated proteins, cell cultures and productivity are limited by the lack of suitable systems to enable stable perfusion culture. Microencapsulation, or entrapping cells within a semi-permeable membrane, offers the potential to generate high cell density cultures and improve the productivity by mimicking the cells natural environment. However, the cells being secluded by the microcapsules membrane are difficult to ...

  8. Dedifferentiated fat cells: A cell source for regenerative medicine

    OpenAIRE

    Jumabay, Medet; Boström, Kristina I.

    2015-01-01

    The identification of an ideal cell source for tissue regeneration remains a challenge in the stem cell field. The ability of progeny cells to differentiate into other cell types is important for the processes of tissue reconstruction and tissue engineering and has clinical, biochemical or molecular implications. The adaptation of stem cells from adipose tissue for use in regenerative medicine has created a new role for adipocytes. Mature adipocytes can easily be isolated from adipose cell su...

  9. Single Cell Characterization of Prostate Cancer-Circulating Tumor Cells

    Science.gov (United States)

    2013-09-01

    al., 2010). In addition, there were a significant number of cell cycle and mitosis associated transcripts in the highly expressed gene set including...red blood cell lysis with 10 volumes of 16 PharmLyse (BD Biosciences) for 15 minutes at room temperature . Remaining cells were pelleted at 4uC for 15...processes (23%, GO:0008152) or the cell cycle (10%, GO:0007049), consistent with mitotically active cells (Fig. 4C). Cell cycle and mitosis associated

  10. Cell of Origin and Cancer Stem Cell Phenotype in Medulloblastomas

    Science.gov (United States)

    2015-07-01

    progenitor cells (NPCs) by expressing an activated form of Notch1 (N1ICD) or oncogenic PIK3CA (PIK3CA*) in the developing mouse cerebellum, using cell...resistance, pediatric cancer, brain tumor, Notch1, PIK3CA, cell of origin, molecular subtypes, neural stem cells, neural progenitor cells, tumor initiation...neural progenitor cells, tumor initiation. 3. ACCOMPLISHMENTS: Major goals of the project: The stated goals of this project are to: 1) test the

  11. Plasma cells negatively regulate the follicular helper T cell program

    OpenAIRE

    2010-01-01

    B lymphocytes differentiate into antibody-secreting cells under the antigen-specific control of follicular helper T (TFH) cells. Here, we demonstrate that isotype-switched plasma cells expressed MHCII, CD80 and CD86 and intracellular machinery required for antigen presentation. Antigen-specific plasma cells could access, process and present sufficient antigen in vivo to induce multiple TH cell functions. Importantly, antigen-primed plasma cells failed to induce interleukin 21 or Bcl-6 in naïv...

  12. Mesothelial cell differentiation into osteoblast- and adipocyte-like cells

    OpenAIRE

    Sally M Lansley; Searles, Richelle G.; Hoi, Aina; Thomas, Carla; Moneta, Helena; Herrick, Sarah E; Thompson, Philip J; Mark, Newman; Sterrett, Gregory F; Prêle, Cecilia M; Mutsaers, Steven E.

    2011-01-01

    Serosal pathologies including malignant mesothelioma (MM) can show features of osseous and/or cartilaginous differentiation although the mechanism for its formation is unknown. Mesothelial cells have the capacity to differentiate into cells with myofibroblast, smooth muscle and endothelial cell characteristics. Whether they can differentiate into other cell types is unclear. This study tests the hypothesis that mesothelial cells can differentiate into cell lineages of the embryonic mesoderm i...

  13. A novel cell subset:Interferon-producing killer dendritic cells

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Recent reports introduce a novel cell subset of DCs with antigenic phenotypes shared by both NK cells and B cells, but without surface markers of pDCs and T cells, appearing to be a chimera of NK cells and DCs, namely interferon-producing killer dendritic cells(IKDCs).IKDCs not only secret type I and type II interferons to recognize and kill tumor cells effectively, but also express MHC-II molecules to present antigens.Thus, IKDCs are considered as important immunosurveilance cells for tumors, providing a link between innate and adaptive immunity.

  14. Cell therapy for diabetes mellitus: an opportunity for stem cells?

    Science.gov (United States)

    Soria, B; Bedoya, F J; Tejedo, J R; Hmadcha, A; Ruiz-Salmerón, R; Lim, S; Martin, F

    2008-01-01

    Diabetes is a chronic disease characterized by a deficit in beta cell mass and a failure of glucose homeostasis. Both circumstances result in a variety of severe complications and an overall shortened life expectancy. Thus, diabetes represents an attractive candidate for cell therapy. Reversal of diabetes can be achieved through pancreas and islet transplantation, but shortage of donor organs has prompted an intensive search for alternative sources of beta cells. This achievement has stimulated the search for appropriate stem cell sources. Both embryonic and adult stem cells have been used to generate surrogate beta cells or otherwise restore beta cell functioning. In this regard, several studies have reported the generation of insulin-secreting cells from embryonic and adult stem cells that normalized blood glucose values when transplanted into diabetic animal models. Due to beta cell complexity, insulin-producing cells generated from stem cells do not possess all beta cell attributes. This indicates the need for further development of methods for differentiation and selection of completely functional beta cells. While these problems are overcome, diabetic patients may benefit from therapeutic strategies based on autologous stem cell therapies addressing late diabetic complications. In this article, we discuss the recent progress in the generation of insulin-producing cells from embryonic and adult stem cells, together with the challenges for the clinical use of diabetes stem cell therapy.

  15. Stem cell biology and cell transplantation therapy in the retina.

    Science.gov (United States)

    Osakada, Fumitaka; Hirami, Yasuhiko; Takahashi, Masayo

    2010-01-01

    Embryonic stem (ES) cells, which are derived from the inner cell mass of mammalian blastocyst stage embryos, have the ability to differentiate into any cell type in the body and to grow indefinitely while maintaining pluripotency. During development, cells undergo progressive and irreversible differentiation into specialized adult cell types. Remarkably, in spite of this restriction in potential, adult somatic cells can be reprogrammed and returned to the naive state of pluripotency found in the early embryo simply by forcing expression of a defined set of transcription factors. These induced pluripotent stem (iPS) cells are molecularly and functionally equivalent to ES cells and provide powerful in vitro models for development, disease, and drug screening, as well as material for cell replacement therapy. Since functional impairment results from cell loss in most central nervous system (CNS) diseases, recovery of lost cells is an important treatment strategy. Although adult neurogenesis occurs in restricted regions, the CNS has poor potential for regeneration to compensate for cell loss. Thus, cell transplantation into damaged or diseased CNS tissues is a promising approach to treating various neurodegenerative disorders. Transplantation of photoreceptors or retinal pigment epithelium cells derived from human ES cells can restore some visual function. Patient-specific iPS cells may lead to customized cell therapy. However, regeneration of retinal function will require a detailed understanding of eye development, visual system circuitry, and retinal degeneration pathology. Here, we review the current progress in retinal regeneration, focusing on the therapeutic potential of pluripotent stem cells.

  16. Embryonic stem cells: prospects for developmental biology and cell therapy.

    Science.gov (United States)

    Wobus, Anna M; Boheler, Kenneth R

    2005-04-01

    Stem cells represent natural units of embryonic development and tissue regeneration. Embryonic stem (ES) cells, in particular, possess a nearly unlimited self-renewal capacity and developmental potential to differentiate into virtually any cell type of an organism. Mouse ES cells, which are established as permanent cell lines from early embryos, can be regarded as a versatile biological system that has led to major advances in cell and developmental biology. Human ES cell lines, which have recently been derived, may additionally serve as an unlimited source of cells for regenerative medicine. Before therapeutic applications can be realized, important problems must be resolved. Ethical issues surround the derivation of human ES cells from in vitro fertilized blastocysts. Current techniques for directed differentiation into somatic cell populations remain inefficient and yield heterogeneous cell populations. Transplanted ES cell progeny may not function normally in organs, might retain tumorigenic potential, and could be rejected immunologically. The number of human ES cell lines available for research may also be insufficient to adequately determine their therapeutic potential. Recent molecular and cellular advances with mouse ES cells, however, portend the successful use of these cells in therapeutics. This review therefore focuses both on mouse and human ES cells with respect to in vitro propagation and differentiation as well as their use in basic cell and developmental biology and toxicology and presents prospects for human ES cells in tissue regeneration and transplantation.

  17. Dye sensitized solar cells.

    Science.gov (United States)

    Wei, Di

    2010-03-16

    Dye sensitized solar cell (DSSC) is the only solar cell that can offer both the flexibility and transparency. Its efficiency is comparable to amorphous silicon solar cells but with a much lower cost. This review not only covers the fundamentals of DSSC but also the related cutting-edge research and its development for industrial applications. Most recent research topics on DSSC, for example, applications of nanostructured TiO(2), ZnO electrodes, ionic liquid electrolytes, carbon nanotubes, graphene and solid state DSSC have all been included and discussed.

  18. Materials for fuel cells

    Directory of Open Access Journals (Sweden)

    Sossina M Haile

    2003-03-01

    Full Text Available Because of their potential to reduce the environmental impact and geopolitical consequences of the use of fossil fuels, fuel cells have emerged as tantalizing alternatives to combustion engines. Like a combustion engine, a fuel cell uses some sort of chemical fuel as its energy source but, like a battery, the chemical energy is directly converted to electrical energy, without an often messy and relatively inefficient combustion step. In addition to high efficiency and low emissions, fuel cells are attractive for their modular and distributed nature, and zero noise pollution. They will also play an essential role in any future hydrogen fuel economy.

  19. Dye Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Di Wei

    2010-03-01

    Full Text Available Dye sensitized solar cell (DSSC is the only solar cell that can offer both the flexibility and transparency. Its efficiency is comparable to amorphous silicon solar cells but with a much lower cost. This review not only covers the fundamentals of DSSC but also the related cutting-edge research and its development for industrial applications. Most recent research topics on DSSC, for example, applications of nanostructured TiO2, ZnO electrodes, ionic liquid electrolytes, carbon nanotubes, graphene and solid state DSSC have all been included and discussed.

  20. Cell Growth Enhancement

    Science.gov (United States)

    1992-01-01

    Exogene Corporation uses advanced technologies to enhance production of bio-processed substances like proteins, antibiotics and amino acids. Among them are genetic modification and a genetic switch. They originated in research for Jet Propulsion Laboratory. Extensive experiments in cell growth through production of hemoglobin to improve oxygen supply to cells were performed. By improving efficiency of oxygen use by cells, major operational expenses can be reduced. Greater product yields result in decreased raw material costs and more efficient use of equipment. A broad range of applications is cited.

  1. Congenital granular cell epulis.

    Science.gov (United States)

    Conrad, Rachel; Perez, Mia C N

    2014-01-01

    Congenital granular cell epulis is a rarely reported lesion of unknown histogenesis with a strong predilection for the maxillary alveolar ridge of newborn girls. Microscopically, it demonstrates nests of polygonal cells with granular cytoplasm, a prominent capillary network, and attenuated overlying squamous epithelium. The lesion lacks immunoreactivity for S-100, laminin, chromogranin, and most other markers except neuron-specific enolase and vimentin. Through careful observation of its unique clinical, histopathologic, and immunohistochemical features, this lesion can be distinguished from the more common adult granular cell tumor as well as other differential diagnoses.

  2. Giant Cell Fibroma

    OpenAIRE

    Tahere Nosratzehi; Lale Maleki

    2013-01-01

    Giant cell fibroma is a fibrous tumor which represents about 2 to 5% of all oral fibrotic proliferations. Compared to traumatic fibroma, giant (traumatic fibroma or irritation fibroma) cell fibroma occurs at a younger age. In about 60% of the cases the lesion is diagnosed within the first three decades of life and is slightly more in women. 50% of the cases is observed in the gum and will appear as a nodule with a papillary surface [1]. The giant cell fibroma is treated by conservative excisi...

  3. Quantum dot solar cells

    CERN Document Server

    Wu, Jiang

    2013-01-01

    The third generation of solar cells includes those based on semiconductor quantum dots. This sophisticated technology applies nanotechnology and quantum mechanics theory to enhance the performance of ordinary solar cells. Although a practical application of quantum dot solar cells has yet to be achieved, a large number of theoretical calculations and experimental studies have confirmed the potential for meeting the requirement for ultra-high conversion efficiency. In this book, high-profile scientists have contributed tutorial chapters that outline the methods used in and the results of variou

  4. PLUTONIUM ELECTROREFINING CELLS

    Science.gov (United States)

    Mullins, L.J. Jr.; Leary, J.A.; Bjorklund, C.W.; Maraman, W.J.

    1963-07-16

    Electrorefining cells for obtaining 99.98% plutonium are described. The cells consist of an impure liquid plutonium anode, a molten PuCl/sub 3/-- alkali or alkaline earth metal chloanode, a molten PuCl/sub 3/-alkali or alkaline earth metal chloride electrolyte, and a nonreactive cathode, all being contained in nonreactive ceramic containers which separate anode from cathode by a short distance and define a gap for the collection of the purified liquid plutonium deposited on the cathode. Important features of these cells are the addition of stirrer blades on the anode lead and a large cathode surface to insure a low current density. (AEC)

  5. Stem cells and transplant arteriosclerosis.

    Science.gov (United States)

    Xu, Qingbo

    2008-05-09

    Stem cells can differentiate into a variety of cells to replace dead cells or to repair damaged tissues. Recent evidence indicates that stem cells are involved in the pathogenesis of transplant arteriosclerosis, an alloimmune initiated vascular stenosis that often results in transplant organ failure. Although the pathogenesis of transplant arteriosclerosis is not yet fully understood, recent developments in stem cell research have suggested novel mechanisms of vascular remodeling in allografts. For example, stem cells derived from the recipient may repair damaged endothelial cells of arteries in transplant organs. Further evidence suggests that stem cells or endothelial progenitor cells may be released from both bone marrow and non-bone marrow tissues. Vascular stem cells appear to replenish cells that died in donor vessels. Concomitantly, stem/progenitor cells may also accumulate in the intima, where they differentiate into smooth muscle cells. However, several issues concerning the contribution of stem cells to the pathogenesis of transplant arteriosclerosis are controversial, eg, whether bone marrow-derived stem cells can differentiate into smooth muscle cells that form neointimal lesions of the vessel wall. This review summarizes recent research on the role of stem cells in transplant arteriosclerosis, discusses the mechanisms of stem cell homing and differentiation into mature endothelial and smooth muscle cells, and highlights the controversial issues in the field.

  6. Primitive human hematopoietic cells give rise to differentially specified daughter cells upon their initial cell division.

    NARCIS (Netherlands)

    Giebel, B.; Zhang, T.; Beckmann, J.; Spanholtz, J.; Wernet, P.; Ho, A.; Punzel, M.

    2006-01-01

    It is often predicted that stem cells divide asymmetrically, creating a daughter cell that maintains the stem-cell capacity, and 1 daughter cell committed to differentiation. While asymmetric stem-cell divisions have been proven to occur in model organisms (eg, in Drosophila), it remains illusive wh

  7. Stem Cell Transplants (For Teens)

    Science.gov (United States)

    ... Loss Surgery? A Week of Healthy Breakfasts Shyness Stem Cell Transplants KidsHealth > For Teens > Stem Cell Transplants Print ... Does it Take to Recover? Coping What Are Stem Cells? As you probably remember from biology class, every ...

  8. Fuel cell system with interconnect

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Zhien; Goettler, Richard

    2016-12-20

    The present invention includes an integrated planar, series connected fuel cell system having electrochemical cells electrically connected via interconnects, wherein the anodes of the electrochemical cells are protected against Ni loss and migration via an engineered porous anode barrier layer.

  9. What is Sickle Cell Disease?

    Science.gov (United States)

    ... page from the NHLBI on Twitter. What Is Sickle Cell Disease? Español The term sickle cell disease (SCD) ... other common forms of SCD. Some Forms of Sickle Cell Disease Hemoglobin SS Hemoglobin SC Hemoglobin Sβ 0 thalassemia ...

  10. What Causes Sickle Cell Disease?

    Science.gov (United States)

    ... page from the NHLBI on Twitter. What Causes Sickle Cell Disease? Abnormal hemoglobin, called hemoglobin S , causes sickle cell ... way that hemoglobin works. ( See Overview. ) How Is Sickle Cell Disease Inherited? When the hemoglobin S gene is inherited ...

  11. Learning about Sickle Cell Disease

    Science.gov (United States)

    ... genetic terms used on this page Learning About Sickle Cell Disease What do we know about heredity and ... Information What do we know about heredity and sickle cell disease? Sickle cell disease is the most common ...

  12. Perivascular cells for regenerative medicine

    NARCIS (Netherlands)

    M. Crisan (Mihaela); M. Corselli (Mirko); W.C. Chen (William); B. Péault (Bruno)

    2012-01-01

    textabstractMesenchymal stem/stromal cells (MSC) are currently the best candidate therapeutic cells for regenerative medicine related to osteoarticular, muscular, vascular and inflammatory diseases, although these cells remain heterogeneous and necessitate a better biological characterization. We an

  13. Rejuvenation of automotive fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yu Seung; Langlois, David A.

    2016-08-23

    A process for rejuvenating fuel cells has been demonstrated to improve the performance of polymer exchange membrane fuel cells with platinum/ionomer electrodes. The process involves dehydrating a fuel cell and exposing at least the cathode of the fuel cell to dry gas (nitrogen, for example) at a temperature higher than the operating temperature of the fuel cell. The process may be used to prolong the operating lifetime of an automotive fuel cell.

  14. The cell biology of T-dependent B cell activation

    DEFF Research Database (Denmark)

    Owens, T; Zeine, R

    1989-01-01

    The requirement that CD4+ helper T cells recognize antigen in association with class II Major Histocompatibility Complex (MHC) encoded molecules constrains T cells to activation through intercellular interaction. The cell biology of the interactions between CD4+ T cells and antigen-presenting cells...... includes multipoint intermolecular interactions that probably involve aggregation of both polymorphic and monomorphic T cell surface molecules. Such aggregations have been shown in vitro to markedly enhance and, in some cases, induce T cell activation. The production of T-derived lymphokines that have been...... implicated in B cell activation is dependent on the T cell receptor for antigen and its associated CD3 signalling complex. T-dependent help for B cell activation is therefore similarly MHC-restricted and involves T-B intercellular interaction. Recent reports that describe antigen-independent B cell...

  15. Concise Review: Asymmetric Cell Divisions in Stem Cell Biology

    Directory of Open Access Journals (Sweden)

    Florian Murke

    2015-11-01

    Full Text Available Somatic stem cells are rare cells with unique properties residing in many organs and tissues. They are undifferentiated cells responsible for tissue regeneration and homeostasis, and contain both the capacity to self-renew in order to maintain their stem cell potential and to differentiate towards tissue-specific, specialized cells. However, the knowledge about the mechanisms controlling somatic stem cell fate decisions remains sparse. One mechanism which has been described to control daughter cell fates in selected somatic stem cell systems is the process of asymmetric cell division (ACD. ACD is a tightly regulated and evolutionary conserved process allowing a single stem or progenitor cell to produce two differently specified daughter cells. In this concise review, we will summarize and discuss current concepts about the process of ACD as well as different ACD modes. Finally, we will recapitulate the current knowledge and our recent findings about ACD in human hematopoiesis.

  16. Dazl Promotes Germ Cell Differentiation from Embryonic Stem Cells

    Institute of Scientific and Technical Information of China (English)

    Zhuo Yu; Ping Ji; Jinping Cao; Shu Zhu; Yao Li; Lin Zheng; Xuejin Chen; Lixin Feng

    2009-01-01

    It has been demonstrated that through the formation of embryoid bodies (Ebs) germ cells can be derived from embryonic stem (ES) cells. Here, we describe a transgene expression approach to derive germ cells directly from ES cells in vitro without EB formation. Through the ectopic expression of Deleted in Azoospermia-Like (Dazl), a germ cell-specific RNA-binding protein,both motile tailed-sperm and oocytes were induced from mouse ES (mES) cells in culture. Furthermore, transient overexpression of Dazl led to suppression of Nanog but induced germ cell nuclear antigen in mES cells. Dazl knockdown resulted in reduction in the expression of germ cell markers including Stella, MVH and Prdm1. Our study indicates that Dazl is a master gene controlling germ cell differentiation and that ectopic expression of Dazl promotes the dynamic differentiation of mouse ES cells into gametes in vitro.

  17. Thin Solid Oxide Cell

    DEFF Research Database (Denmark)

    2010-01-01

    The present invention relates to a thin and in principle unsupported solid oxide cell, comprising at least a porous anode layer, an electrolyte layer and a porous cathode layer, wherein the anode layer and the cathode layer comprise an electrolyte material, at least one metal and a catalyst...... material, and wherein the overall thickness of the thin reversible cell is about 150 [mu]m or less, and to a method for producing same. The present invention also relates to a thin and in principle unsupported solid oxide cell, comprising at least a porous anode layer, an electrolyte layer and a porous...... cathode layer, wherein the anode layer and the cathode layer comprise an electrolyte material and a catalyst material, wherein the electrolyte material is doper zirconia, and wherein the overall thickness of the thin reversible cell is about 150 [mu]m or less, and to a method for producing same...

  18. Colorful Microbial Cell Factories

    DEFF Research Database (Denmark)

    Petersen, Pia Damm

    Yeast cell factories are powerful tools used for the production of high-value natural compounds otherwise not easily available. Many bioactive and industrially important plant secondary metabolites can be produced in yeast by engineering their biosynthetic pathways into yeast cells, as these both...... anthocyanins. Yeast cell factories present a platform to circumvent the problem of low yields of interesting molecular structures in plant tissues, as hand-picking of desired enzyme activities allows for specific biosynthesis of the precise pigment of interest, as well as choosing more stable structures...... for heterologous biosynthesis is possible. In cell factories, great improvements in yields can be achieved through molecular engineering of flux from endogenous yeast precursors, e.g. by elimination of by-product formation, and by genetic optimization of pathway components, such as fine-tuning of expression levels...

  19. Mammary epithelial cell

    DEFF Research Database (Denmark)

    Kass, Laura; Erler, Janine Terra; Dembo, Micah

    2007-01-01

    a repertoire of transmembrane receptors, of which integrins are the best characterized. Integrins modulate cell fate by reciprocally transducing biochemical and biophysical cues between the cell and the extracellular matrix, facilitating processes such as embryonic branching morphogenesis and lactation...... in the mammary gland. During breast development and cancer progression, the extracellular matrix is dynamically altered such that its composition, turnover, processing and orientation change dramatically. These modifications influence mammary epithelial cell shape, and modulate growth factor and hormonal...... responses to regulate processes including branching morphogenesis and alveolar differentiation. Malignant transformation of the breast is also associated with significant matrix remodeling and a progressive stiffening of the stroma that can enhance mammary epithelial cell growth, perturb breast tissue...

  20. Plasma cell leukemia

    DEFF Research Database (Denmark)

    Fernández de Larrea, C; Kyle, R A; Durie, B G M

    2013-01-01

    Plasma cell leukemia (PCL) is a rare and aggressive variant of myeloma characterized by the presence of circulating plasma cells. It is classified as either primary PCL occurring at diagnosis or as secondary PCL in patients with relapsed/refractory myeloma. Primary PCL is a distinct clinic......-pathological entity with different cytogenetic and molecular findings. The clinical course is aggressive with short remissions and survival duration. The diagnosis is based upon the percentage (≥ 20%) and absolute number (≥ 2 × 10(9)/l) of plasma cells in the peripheral blood. It is proposed that the thresholds...... regimens and bortezomib-based regimens are recommended followed by high-dose therapy with autologous stem cell transplantation if feasible. Allogeneic transplantation can be considered in younger patients. Prospective multicenter studies are required to provide revised definitions and better understanding...