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Sample records for k562 cell proliferation

  1. Implication of unfolded protein response in resveratrol-induced inhibition of K562 cell proliferation

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    Liu, Bao-Qin; Gao, Yan-Yan; Niu, Xiao-Fang [Department of Biochemistry and Molecular Biology, China Medical University, Shenyang 110001 (China); Xie, Ji-Sheng [Youjiang Medical College for Nationalities, Guangxi 533000 (China); Meng, Xin; Guan, Yifu [Department of Biochemistry and Molecular Biology, China Medical University, Shenyang 110001 (China); Wang, Hua-Qin, E-mail: wanghq_doctor@hotmail.com [Department of Biochemistry and Molecular Biology, China Medical University, Shenyang 110001 (China)

    2010-01-01

    Resveratrol (RES), a natural plant polyphenol, is an effective inducer of cell cycle arrest and apoptosis in a variety of carcinoma cell types. In addition, RES has been reported to inhibit tumorigenesis in several animal models suggesting that it functions as a chemopreventive and anti-tumor agent in vivo. The chemopreventive and chemotherapeutic properties associated with resveratrol offer promise for the design of new chemotherapeutic agents. However, the mechanisms by which RES mediates its effects are not yet fully understood. In this study, we showed that RES caused cell cycle arrest and proliferation inhibition via induction of unfolded protein response (UPR) in human leukemia K562 cell line. Treatment of K562 cells with RES induced a number of signature UPR markers, including transcriptional induction of GRP78 and CHOP, phosphorylation of eukaryotic initiation factor 2{alpha} (eIF2{alpha}), ER stress-specific XBP-1 splicing, suggesting the induction of UPR by RES. RES inhibited proliferation of K562 in a concentration-dependent manner. Flow cytometric analyses revealed that K562 cells were arrested in G1 phase upon RES treatment. Salubrinal, an eIF2{alpha} inhibitor, or overexpression of dominant negative mutants of PERK or eIF2{alpha}, effectively restored RES-induced cell cycle arrest, underscoring the important role of PERK/eIF2{alpha} branch of UPR in RES-induced inhibition of cell proliferation.

  2. Implication of unfolded protein response in resveratrol-induced inhibition of K562 cell proliferation

    International Nuclear Information System (INIS)

    Liu, Bao-Qin; Gao, Yan-Yan; Niu, Xiao-Fang; Xie, Ji-Sheng; Meng, Xin; Guan, Yifu; Wang, Hua-Qin

    2010-01-01

    Resveratrol (RES), a natural plant polyphenol, is an effective inducer of cell cycle arrest and apoptosis in a variety of carcinoma cell types. In addition, RES has been reported to inhibit tumorigenesis in several animal models suggesting that it functions as a chemopreventive and anti-tumor agent in vivo. The chemopreventive and chemotherapeutic properties associated with resveratrol offer promise for the design of new chemotherapeutic agents. However, the mechanisms by which RES mediates its effects are not yet fully understood. In this study, we showed that RES caused cell cycle arrest and proliferation inhibition via induction of unfolded protein response (UPR) in human leukemia K562 cell line. Treatment of K562 cells with RES induced a number of signature UPR markers, including transcriptional induction of GRP78 and CHOP, phosphorylation of eukaryotic initiation factor 2α (eIF2α), ER stress-specific XBP-1 splicing, suggesting the induction of UPR by RES. RES inhibited proliferation of K562 in a concentration-dependent manner. Flow cytometric analyses revealed that K562 cells were arrested in G1 phase upon RES treatment. Salubrinal, an eIF2α inhibitor, or overexpression of dominant negative mutants of PERK or eIF2α, effectively restored RES-induced cell cycle arrest, underscoring the important role of PERK/eIF2α branch of UPR in RES-induced inhibition of cell proliferation.

  3. Retinoic acid receptor gamma impacts cellular adhesion, Alpha5Beta1 integrin expression and proliferation in K562 cells.

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    Kelley, Melissa D; Phomakay, Raynin; Lee, Madison; Niedzwiedz, Victoria; Mayo, Rachel

    2017-01-01

    The interplay between cellular adhesion and proliferation is complex; however, integrins, particularly the α5β1 subset, play a pivotal role in orchestrating critical cellular signals that culminate in cellular adhesion and growth. Retinoids modify the expression of a variety of adhesive/proliferative signaling proteins including α5β1 integrins; however, the role of specific retinoic acid receptors involved in these processes has not been elucidated. In this study, the effect of all-trans-retinoic acid receptor (RAR) agonists on K562 cellular adhesion, proliferation, and α5β1 integrin cell surface expression was investigated. RARγ agonist exposure increased K562 cellular adhesion to RGD containing extracellular matrix proteins fibronectin and FN-120 in a time- and concentration dependent manner, while RARα or RARβ agonist treatment had no effect on cellular adhesion. Due to the novel RARγ- dependent cellular adhesion response exhibited by K562 cells, we examined α5 and β1 integrin subunit expression when K562 cells were exposed to retinoid agonists or vehicle for 24, 48, 72 or 96 hours. Our data demonstrates no differences in K562 cell surface expression of the α5 integrin subunit when cells were exposed to RARα, RARβ, or RARγ agonists for all time points tested. In contrast, RARγ agonist exposure resulted in an increase in cell surface β1 integrin subunit expression within 48 hours that was sustained at 72 and 96 hours. Finally, we demonstrate that while exposure to RARα or RARβ agonists have no effect on K562 cellular proliferation, the RARγ agonist significantly dampens K562 cellular proliferation levels in a time- and concentration- dependent manner. Our study is the first to report that treatment with a RARγ specific agonist augments cellular adhesion to α5β1 integrin substrates, increases cell surface levels of the β1 integrin subunit, and dampens cellular proliferation in a time and concentration dependent manner in a human

  4. Musashi2 modulates K562 leukemic cell proliferation and apoptosis involving the MAPK pathway

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    Zhang, Huijuan; Tan, Shi; Wang, Juan; Chen, Shana; Quan, Jing; Xian, Jingrong; Zhang, Shuai shuai; He, Jingang; Zhang, Ling, E-mail: lingzhang@cqmu.edu.cn

    2014-01-01

    The RNA-binding protein Musashi2 (Msi2) has been identified as a master regulator within a variety of stem cell populations via the regulation of translational gene expression. A recent study has suggested that Msi2 is strongly expressed in leukemic cells of acute myeloid leukemia patients, and elevated Msi2 is associated with poor prognosis. However, the potential role of Msi2 in leukemogenesis is still not well understood. Here, we investigated the effect of Msi2 knockdown on the biological properties of leukemic cells. High expression of Msi2 was found in K562 and KG-1a leukemic cell lines, and low expression was observed in the U937 cell line. We transduced K562 cells with two independent adenoviral shRNA vectors targeting Msi2 and confirmed knockdown of Msi2 at the mRNA and protein levels. Msi2 silencing inhibited cell growth and caused cell cycle arrest by increasing the expression of p21 and decreasing the expression of cyclin D1 and cdk2. In addition, knockdown of Msi2 promoted cellular apoptosis via the upregulation of Bax and downregulation of Bcl-2 expression. Furthermore, Msi2 knockdown resulted in the inactivation of the ERK/MAPK and p38/MAPK pathways, but no remarkable change in p-AKT was observed. These data provide evidence that Msi2 plays an important role in leukemogenesis involving the MAPK signaling pathway, which indicates that Msi2 may be a novel target for leukemia treatment. - Highlights: • Knockdown of Msi2 inhibited K562 cell growth and arrested cell cycle progression. • Knockdown of Msi2 induced K562 cell apoptosis via the regulation of Bax and Bcl-2. • The MAPK pathway was involved in the process of Msi2-mediated leukemogenesis. • Our data indicate that Msi2 is a potential new target for leukemia treatment.

  5. 9-cis-retinoic Acid and troglitazone impacts cellular adhesion, proliferation, and integrin expression in K562 cells.

    Science.gov (United States)

    Hanson, Amanda M; Gambill, Jessica; Phomakay, Venusa; Staten, C Tyler; Kelley, Melissa D

    2014-01-01

    Retinoids are established pleiotropic regulators of both adaptive and innate immune responses. Recently, troglitazone, a PPAR gamma agonist, has been demonstrated to have anti-inflammatory effects. Separately, retinoids and troglitazone are implicated in immune related processes; however, their combinatory role in cellular adhesion and proliferation has not been well established. In this study, the effect of 9-cis-retinoic acid (9-cis-RA) and troglitazone on K562 cellular adhesion and proliferation was investigated. Troglitazone exposure decreased K562 cellular adhesion to RGD containing extracellular matrix proteins fibronectin, FN-120, and vitronectin in a concentration and time-dependent manner. In the presence of troglitazone, 9-cis-retinoic acid restores cellular adhesion to levels comparable to vehicle treatment alone on fibronectin, FN-120, and vitronectin substrates within 72 hours. Due to the prominent role of integrins in attachment to extracellular matrix proteins, we evaluated the level of integrin α5 subunit expression. Troglitazone treatment results in decrease in α5 subunit expression on the cell surface. In the presence of both agonists, cell surface α5 subunit expression was restored to levels comparable to vehicle treatment alone. Additionally, troglitazone and 9-cis-RA mediated cell adhesion was decreased in the presence of a function blocking integrin alpha 5 inhibitor. Further, through retinoid metabolic profiling and HPLC analysis, our study demonstrates that troglitazone augments retinoid availability in K562 cells. Finally, we demonstrate that troglitazone and 9-cis-retinoic acid synergistically dampen cellular proliferation in K562 cells. Our study is the first to report that the combination of troglitazone and 9-cis-retinoic acid restores cellular adhesion, alters retinoid availability, impacts integrin expression, and dampens cellular proliferation in K562 cells.

  6. Effect of JTV1 gene on the proliferation and apoptosis of K562 cells and its mechanism

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    Yan WU

    2011-05-01

    Full Text Available Objective To investigate the effect of tumor-suppressing gene JTV1 on proliferation and apoptosis of leukemic K562 cells,and the changes in apoptosis factors Bcl-2,C-myc and Bax genes.Methods The recombinate vector pcDNA3.1-JTV1,and the empty vector pcDNA3.1 were transfected into K562 cells as control.The cell proliferation of K562 cells was evaluated by colony formation assay;the cell cycle and apoptosis rate were assessed by flow cytometry(FCM;the mRNA levels of apoptosis related genes Bax,Bcl-2 and C-myc were determined by RT-PCR;the protein levels of Bax,Bcl-2 and C-myc were assayed by Western Blotting.Results The colony formation assay showed that the proliferation of K562 cells decreased when the expression of JTV1 gene was up-regulated.FCM assay showed that the G phase cells in pcDNA3.1-JTV1 positive transfection group increased compared with that of the control group and the pcDNA3.1 empty vector transfected group,and the differences were statistically significant(P < 0.05.Compared with the control group and the empty vector group,the mRNA transcription level and the protein translation level of Bax gene increased significantly,and the mRNA transcription level and the protein translation level of Bcl-2 and C-myc gene were reduced significantly(P < 0.05.Conclusions The expressions of Bcl-2 and C-myc gene are inhibited when the gene JTV1 is up-regulated,leading to an increase in Bax gene expression,inhibition of K562 cell proliferation,and promotion of tumor cells apoptosis.Over expression of JTV1 gene can inhibit the proliferation of K562 cells and promote cell apoptosis by inhibiting Bcl-2 and C-myc expression and up-regulating that of Bax.

  7. Putative tyrosine kinases expressed in K-562 human leukemia cells

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    Partanen, J.; Maekelae, T.P.; Lehvaeslaiho, H.; Alitalo, K.; Alitalo, R.

    1990-01-01

    Tyrosine phosphorylation is important in the transmission of growth and differentiation signals; known tyrosine kinases include several oncoproteins and growth factor receptors. Interestingly, some differentiated cell types, such as erythrocytes and platelets contain high amounts of phosphotyrosine. The authors analyzed tyrosine kinases expressed in the K-562 chronic myelogenous leukemia cell line, which has a bipotential erythroid and megakaryoblastoid differentiation capacity. Analysis of 359 polymerase chain reaction-amplified cDNA clones led to the identification of 14 different tyrosine kinase-related sequences (JTK1-14). Two of the clones (JTK2 and JTK4) represent unusual members of the fibroblast growth factor receptor gene family, and the clones JTK5, JTK11, and JTK14 may also belong to the family of receptor tyrosine kinases but lack a close relationship to any known tyrosine kinase. Each of these different genes has its own characteristic expression pattern in K-562 cells and several other human tumor cell lines. In addition, the JTK11 and JTK14 mRNAs are induced during the megakaryoblastoid differentiation of K-562 cells. These tyrosine kinases may have a role in the differentiation of megakaryoblasts or in the physiology of platelets

  8. Anti-Proliferative and Apoptotic Effects of Beta-Ionone in Human Leukemia Cell Line K562

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    Zohreh Faezizadeh

    2016-06-01

    Full Text Available Background Beta-ionone is an aroma compound found in the Rosaceae family. Some evidence supported that beta-ionone has a great potential for cancer prevention. To date, the anti-proliferative and apoptotic effects of beta-ionone in human leukemia cell line K562 were not studied. Objectives Hence, we investigated whether beta-ionone could inhibit cell growth and induce apoptosis in the K562 cells. Materials and Methods In this experimental study, human leukemia cell line K562 was cultured and anti-proliferation effect of beta-ionone with different doses (25 - 400 µm at different times (24 - 96 hours on treated cells was evaluated by the MTT assay. To determine apoptosis rate, the Hoechst 33342 staining and flow cytometry was performed. Results The MTT assay showed that beta-ionone inhibited proliferation of K562 cells in a dose-dependent manner significantly (P = 0.0008. Moreover, the increased apoptotic rate was found after incubation of K562 cells with 200 µm beta-ionone. The Hoechst staining and flow cytometry analysis indicated that beta-ionone could increase apoptosis of K562 cells in a dose-dependent manner. Conclusions The results demonstrated that beta-ionone has anti-proliferative and apoptotic effects on K562 cells, and in the future may be used in the treatment of some leukemia sub-types.

  9. The effect of β-ionone on telomerase activity in the human leukemia cell line K562

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    Zohreh Faezizadeh

    2015-06-01

    Full Text Available Background: Telomerase is highly activated in most human cancer cells, therefore, its inhibition has been proposed as a novel and promising strategy for cancer therapy. Many plant-derived anticancer agents act through inhibition of telomerase activity and induction of apoptosis. β-ionone, a carotenoid compound isolated from Roseaceae, has been reported to possess anticancer properties. The present study was undertaken to examine the mechanism of β-ionone-induced apoptosis in human leukemia cell line K562 with special emphasis on its role in telomerase inhibition. Method: In this study the anti-proliferation effect of β-ionone on K562 cells was evaluated by MTT assay. Apoptosis rate was detected by Hoechst staining and flow cytometry analysis. Telomerase activity was measured by (TRAP ELISA assay. Results: Exposure of K562 cells to β-ionone caused a dose-dependent decrease in proliferation. Flow cytometry analysis and Hoechst staining showed that percentage of apoptotic cells markedly increased with an increase in β-ionone concentration. Compared to control cells, treatment of K562 cells with β-ionone resulted in a significant decrease of telomerase activity. Moreover, a positive correlation was detected between telomerase inhibition and apoptosis induction in the treated K562 cells. Conclusion: Based on these results, β-ionone is an appropriate candidate for inhibiting telomerase activity in K562 cells. Therefore, it may be utilized as a novel drug against some leukemia cell lines.

  10. Vorinostat enhances chemosensitivity to arsenic trioxide in K562 cell line

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    Nainong Li

    2015-05-01

    Full Text Available Objective. This study aimed to investigate the chemosensitive augmentation effect and mechanism of HDAC inhibitor Vorinostat (SAHA in combination with arsenic trioxide (ATO on proliferation and apoptosis of K562 cells.Methods. The CCK-8 assay was used to compare proliferation of the cells. Annexin-V and PI staining by flow cytometry and acridine orange/ethidium bromide stains were used to detect and quantify apoptosis. Western blot was used to detect expression of p21, Akt, pAkt, p210, Acetyl-Histone H3, and Acetyl-Histone H4 proteins.Results. SAHA and ATO inhibited proliferation of K562 cells in an additive and time- and dose-dependent manner. SAHA in combination with ATO showed significant apoptosis of K562 cells in comparison to the single drugs alone (p < 0.01. Both SAHA and ATO alone and in combination showed lower levels of p210 expression. SAHA and SAHA and ATO combined treatment showed increased levels of Acetyl-Histone H3 and Acetyl-Histone H4 protein expression. SAHA alone showed increased expression of p21, while ATO alone and in combination with SAHA showed no significant change. SAHA and ATO combined therapy showed lower levels of Akt and pAkt protein expression than SAHA or ATO alone.Conclusion. SAHA and ATO combined treatment inhibited proliferation, induced apoptosis, and showed a chemosensitive augmentation effect on K562 cells. The mechanism might be associated with increasing histone acetylation levels as well as regulating the Akt signaling pathway.

  11. Potent antitumor activities of recombinant human PDCD5 protein in combination with chemotherapy drugs in K562 cells

    International Nuclear Information System (INIS)

    Shi, Lin; Song, Quansheng; Zhang, Yingmei; Lou, Yaxin; Wang, Yanfang; Tian, Linjie; Zheng, Yi; Ma, Dalong; Ke, Xiaoyan; Wang, Ying

    2010-01-01

    Conventional chemotherapy is still frequently used. Programmed cell death 5 (PDCD5) enhances apoptosis of various tumor cells triggered by certain stimuli and is lowly expressed in leukemic cells from chronic myelogenous leukemia patients. Here, we describe for the first time that recombinant human PDCD5 protein (rhPDCD5) in combination with chemotherapy drugs has potent antitumor effects on chronic myelogenous leukemia K562 cells in vitro and in vivo. The antitumor efficacy of rhPDCD5 protein with chemotherapy drugs, idarubicin (IDR) or cytarabine (Ara-C), was examined in K562 cells in vitro and K562 xenograft tumor models in vivo. rhPDCD5 protein markedly increased the apoptosis rates and decreased the colony-forming capability of K562 cells after the combined treatment with IDR or Ara-C. rhPDCD5 protein by intraperitoneal administration dramatically improved the antitumor effects of IDR treatment in the K562 xenograft model. The tumor sizes and cell proliferation were significantly decreased; and TUNEL positive cells were significantly increased in the combined group with rhPDCD5 protein and IDR treatment compared with single IDR treatment groups. rhPDCD5 protein, in combination with IDR, has potent antitumor effects on chronic myelogenous leukemia K562 cells and may be a novel and promising agent for the treatment of chronic myelogenous leukemia.

  12. Circumvention of acquired resistance to doxorubicin in K562 human leukemia cells by oxatomide.

    Science.gov (United States)

    Ishikawa, M; Fujita, R; Furusawa, S; Takayanagi, M; Sasaki, K; Satoh, S

    2001-10-01

    We studied the effect of oxatomide, an antiallergic drug, on the resistance of K562 cells to doxorubicin. Oxatomide synergistically potentiated the cytotoxicity of doxorubicin in doxorubicin-resistant K562 cells (K562/DXR) at a concentration of 1-10 microM, but had hardly any synergistic effect on the parental cell line (K562) at the same concentration. Oxatomide inhibit P-glycoprotein pump-efflux activity and the binding of [3H]-azidopine to the cell-surface protein P-glycoprotein, in a dose-related manner. These results indicate that oxatomide reverses the multidrug-resistance phenotype through direct interaction with P-glycoprotein.

  13. Caveolin-1 contributes to realgar nanoparticle therapy in human chronic myelogenous leukemia K562 cells

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    Shi D

    2016-11-01

    Full Text Available Dan Shi,1,* Yan Liu,1,* Ronggang Xi,1 Wei Zou,2 Lijun Wu,3 Zhiran Zhang,1 Zhongyang Liu,1 Chao Qu,1 Baoli Xu,1 Xiaobo Wang1 1Department of Pharmacy, The 210th Hospital of People’s Liberation Army, 2College of Life Science, Liaoning Normal University, Dalian, Liaoning, 3Department of Pharmaceutics, College of Pharmacy, Harbin Medical University, Harbin, Heilongjiang, People’s Republic of China *These authors contributed equally to this work Abstract: Chronic myelogenous leukemia (CML is characterized by the t(9;22 (q34;q11-associated Bcr-Abl fusion gene, which is an essential element of clinical diagnosis. As a traditional Chinese medicine, realgar has been widely used for the treatment of various diseases for >1,500 years. Inspired by nano-drug, realgar nanoparticles (NPs have been prepared with an average particle size of <100 nm in a previous work. Compared with coarse realgar, the realgar NPs have higher bioavailability. As a principal constituent protein of caveolae, caveolin-1 (Cav-1 participates in regulating various cellular physiological and pathological processes including tumorigenesis and tumor development. In previous studies, it was found that realgar NPs can inhibit several types of tumor cell proliferation. However, the therapeutic effect of realgar NPs on CML has not been fully elucidated. In the present paper, it was demonstrated that realgar NPs can inhibit the proliferation of K562 cells and degrade Bcr-Abl fusion protein effectively. Both apoptosis and autophagy were activated in a dose-dependent manner in realgar NPs treated cells, and the induction of autophagy was associated with class I phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin pathway. Morphological analysis indicated that realgar NPs induced differentiation effectively in CML cells. Furthermore, it was identified that Cav-1 might play a crucial role in realgar NP therapy. In order to study the effects of Cav-1 on K562 cells during

  14. Effects of P-Glycoprotein and Its Inhibitors on Apoptosis in K562 Cells

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    Yaqiong Zu

    2014-08-01

    Full Text Available P-glycoprotein (P-gp is a major factor in multidrug resistance (MDR which is a serious obstacle in chemotherapy. P-gp has also been implicated in causing apoptosis of tumor cells, which was shown to be another important mechanism of MDR recently. To study the influence of P-gp in tumor cell apoptosis, K562/A cells (P-gp+ and K562/S cells (P-gp− were subjected to doxorubicin (Dox, serum withdrawal, or independent co-incubation with multiple P-gp inhibitors, including valspodar (PSC833, verapamil (Ver and H108 to induce apoptosis. Apoptosis was simultaneously detected by apoptotic rate, cell cycle by flow cytometry and cysteine aspartic acid-specific protease 3 (caspase 3 activity by immunoassay. Cytotoxicity and apoptosis induced by PSC833 were evaluated through an MTT method and apoptosis rate, and cell cycle combined with caspase 3 activity, respectively. The results show that K562/A cells are more resistant to apoptosis and cell cycle arrest than K562/S cells after treatment with Dox or serum deprivation. The apoptosis of K562/A cells increased after co-incubation with each of the inhibitors of P-gp. P-gp inhibitors also enhanced cell cycle arrest in K562/A cell. PSC833 most strikingly decreased viability and led to apoptosis and S phase arrest of cell cycle in K562/A cells. Our study demonstrates that P-gp inhibits the apoptosis of tumor cells in addition to participating in the efflux of intracellular chemotherapy drugs. The results of the caspase 3 activity assay also suggest that the role of P-gp in apoptosis avoidance is caspase-related.

  15. 5-(2-Carboxyethenyl) isatin derivative induces G2/M cell cycle arrest and apoptosis in human leukemia K562 cells

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    Zhou, Yao; Zhao, Hong-Ye; Han, Kai-Lin; Yang, Yao; Song, Bin-Bin; Guo, Qian-Nan; Fan, Zhen-Chuan; Zhang, Yong-Min; Teng, Yu-Ou; Yu, Peng

    2014-01-01

    Highlights: • 5-(2-Carboxyethenyl) isatin derivative (HKL 2H) inhibited K562’s proliferation. • HKL 2H caused the morphology change of G 2 /M phase arrest and typical apoptosis. • HKL 2H induced G2/M cell cycle phase arrest in K562 cells. • HKL 2H induced apoptosis in K562 cells through the mitochondrial pathway. - Abstract: Our previous study successfully identified that the novel isatin derivative (E)-methyl 3-(1-(4-methoxybenzyl)-2,3-dioxoindolin-5-yl) acrylate (HKL 2H) acts as an anticancer agent at an inhibitory concentration (IC 50 ) level of 3 nM. In this study, the molecular mechanism how HKL 2H induces cytotoxic activity in the human chronic myelogenous leukemia K562 cells was investigated. Flow cytometric analysis showed that the cells were arrested in the G 2 /M phase and accumulated subsequently in the sub-G 1 phase in the presence of HKL 2H. HKL 2H treatment down-regulated the expressions of CDK1 and cyclin B but up-regulated the level of phosphorylated CDK1. Annexin-V staining and the classic DNA ladder studies showed that HKL 2H induced the apoptosis of K562 cells. Our study further showed that HKL 2H treatment caused the dissipation of mitochondrial membrane potential, activated caspase-3 and lowered the Bcl-2/Bax ratio in K562 cells, suggesting that the HKL 2H-causing programmed cell death of K562 cells was caused via the mitochondrial apoptotic pathway. Taken together, our data demonstrated that HKL 2H, a 5-(2-carboxyethenyl) isatin derivative, notably induces G 2 /M cell cycle arrest and mitochondrial-mediated apoptosis in K562 cells, indicating that this compound could be a promising anticancer candidate for further investigation

  16. 5-(2-Carboxyethenyl) isatin derivative induces G{sub 2}/M cell cycle arrest and apoptosis in human leukemia K562 cells

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    Zhou, Yao; Zhao, Hong-Ye; Han, Kai-Lin; Yang, Yao; Song, Bin-Bin; Guo, Qian-Nan [Key Laboratory of Industrial Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457 (China); Tianjin Key Laboratory of Industry Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457 (China); Fan, Zhen-Chuan [Key Laboratory of Food Nutrition and Safety (Tianjin University of Science and Technology), Ministry of Education, Tianjin 300457 (China); Obesita and Algaegen LLC, College Station, TX 77845 (United States); Zhang, Yong-Min [Université Pierre et Marie Curie-Paris 6, Institut Parisien de Chimie Moléculaire UMR CNRS 8232, 4 Place Jussieu, 75005 Paris (France); Teng, Yu-Ou, E-mail: tyo201485@tust.edu.cn [Key Laboratory of Industrial Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457 (China); Tianjin Key Laboratory of Industry Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457 (China); Yu, Peng, E-mail: yupeng@tust.edu.cn [Key Laboratory of Industrial Microbiology, Ministry of Education, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457 (China); Tianjin Key Laboratory of Industry Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457 (China)

    2014-08-08

    Highlights: • 5-(2-Carboxyethenyl) isatin derivative (HKL 2H) inhibited K562’s proliferation. • HKL 2H caused the morphology change of G{sub 2}/M phase arrest and typical apoptosis. • HKL 2H induced G2/M cell cycle phase arrest in K562 cells. • HKL 2H induced apoptosis in K562 cells through the mitochondrial pathway. - Abstract: Our previous study successfully identified that the novel isatin derivative (E)-methyl 3-(1-(4-methoxybenzyl)-2,3-dioxoindolin-5-yl) acrylate (HKL 2H) acts as an anticancer agent at an inhibitory concentration (IC{sub 50}) level of 3 nM. In this study, the molecular mechanism how HKL 2H induces cytotoxic activity in the human chronic myelogenous leukemia K562 cells was investigated. Flow cytometric analysis showed that the cells were arrested in the G{sub 2}/M phase and accumulated subsequently in the sub-G{sub 1} phase in the presence of HKL 2H. HKL 2H treatment down-regulated the expressions of CDK1 and cyclin B but up-regulated the level of phosphorylated CDK1. Annexin-V staining and the classic DNA ladder studies showed that HKL 2H induced the apoptosis of K562 cells. Our study further showed that HKL 2H treatment caused the dissipation of mitochondrial membrane potential, activated caspase-3 and lowered the Bcl-2/Bax ratio in K562 cells, suggesting that the HKL 2H-causing programmed cell death of K562 cells was caused via the mitochondrial apoptotic pathway. Taken together, our data demonstrated that HKL 2H, a 5-(2-carboxyethenyl) isatin derivative, notably induces G{sub 2}/M cell cycle arrest and mitochondrial-mediated apoptosis in K562 cells, indicating that this compound could be a promising anticancer candidate for further investigation.

  17. The role of DNA methylation in catechol-enhanced erythroid differentiation of K562 cells

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    Li, Xiao-Fei; Wu, Xiao-Rong; Xue, Ming; Wang, Yan; Wang, Jie; Li, Yang; Suriguga,; Zhang, Guang-Yao; Yi, Zong-Chun, E-mail: yizc@buaa.edu.cn

    2012-11-15

    Catechol is one of phenolic metabolites of benzene in vivo. Catechol is also widely used in pharmaceutical and chemical industries. In addition, fruits, vegetables and cigarette smoke also contain catechol. Our precious study showed that several benzene metabolites (phenol, hydroquinone, and 1,2,4-benzenetriol) inhibited erythroid differentiation of K562 cells. In present study, the effect of catechol on erythroid differentiation of K562 cells was investigated. Moreover, to address the role of DNA methylation in catechol-induced effect on erythroid differentiation in K562 cells, methylation levels of erythroid-specific genes were analyzed by Quantitative MassARRAY methylation analysis platform. Benzidine staining showed that exposure to catechol enhanced hemin-induced hemoglobin accumulation in K562 cells in concentration- and time-dependent manners. The mRNA expression of erythroid specific genes, including α-globin, β-globin, γ-globin, erythroid 5-aminolevulinate synthase, erythroid porphobilinogen deaminase, and transcription factor GATA-1 genes, showed a significant concentration-dependent increase in catechol-treated K562 cells. The exposure to catechol caused a decrease in DNA methylation levels at a few CpG sites in some erythroid specific genes including α-globin, β-globin and erythroid porphobilinogen deaminase genes. These results indicated that catechol improved erythroid differentiation potency of K562 cells at least partly via up-regulating transcription of some erythroid related genes, and suggested that inhibition of DNA methylation might be involved in up-regulated expression of some erythroid related genes. -- Highlights: ► Catechol enhanced hemin-induced hemoglobin accumulation. ► Exposure to catechol resulted in up-regulated expression of erythroid genes. ► Catechol reduced methylation levels at some CpG sites in erythroid genes.

  18. The role of DNA methylation in catechol-enhanced erythroid differentiation of K562 cells

    International Nuclear Information System (INIS)

    Li, Xiao-Fei; Wu, Xiao-Rong; Xue, Ming; Wang, Yan; Wang, Jie; Li, Yang; Suriguga,; Zhang, Guang-Yao; Yi, Zong-Chun

    2012-01-01

    Catechol is one of phenolic metabolites of benzene in vivo. Catechol is also widely used in pharmaceutical and chemical industries. In addition, fruits, vegetables and cigarette smoke also contain catechol. Our precious study showed that several benzene metabolites (phenol, hydroquinone, and 1,2,4-benzenetriol) inhibited erythroid differentiation of K562 cells. In present study, the effect of catechol on erythroid differentiation of K562 cells was investigated. Moreover, to address the role of DNA methylation in catechol-induced effect on erythroid differentiation in K562 cells, methylation levels of erythroid-specific genes were analyzed by Quantitative MassARRAY methylation analysis platform. Benzidine staining showed that exposure to catechol enhanced hemin-induced hemoglobin accumulation in K562 cells in concentration- and time-dependent manners. The mRNA expression of erythroid specific genes, including α-globin, β-globin, γ-globin, erythroid 5-aminolevulinate synthase, erythroid porphobilinogen deaminase, and transcription factor GATA-1 genes, showed a significant concentration-dependent increase in catechol-treated K562 cells. The exposure to catechol caused a decrease in DNA methylation levels at a few CpG sites in some erythroid specific genes including α-globin, β-globin and erythroid porphobilinogen deaminase genes. These results indicated that catechol improved erythroid differentiation potency of K562 cells at least partly via up-regulating transcription of some erythroid related genes, and suggested that inhibition of DNA methylation might be involved in up-regulated expression of some erythroid related genes. -- Highlights: ► Catechol enhanced hemin-induced hemoglobin accumulation. ► Exposure to catechol resulted in up-regulated expression of erythroid genes. ► Catechol reduced methylation levels at some CpG sites in erythroid genes.

  19. Unravelling pathways downstream Sox6 induction in K562 erythroid cells by proteomic analysis

    KAUST Repository

    Barbarani, Gloria; Ronchi, Antonella; Ruoppolo, Margherita; Santorelli, Lucia; Steinfelder, Robert; Elangovan, Sudharshan; Fugazza, Cristina; Caterino, Marianna

    2017-01-01

    are accompanied with a reduced survival of Sox6-/- red blood cells, resulting in a compensated anemia. Sox6-overexpression in K562cells and in human primary ex vivo erythroid cultures enhances erythroid differentiation and leads to hemoglobinization, the hallmark

  20. The proteomic study of sodium butyrate antiproliferative/cytodifferentiation effects on K562 cells

    Czech Academy of Sciences Publication Activity Database

    Grebeňová, D.; Kuželová, K.; Pluskalová, M.; Pešlová, G.; Halada, Petr; Hrkal, Z.

    2006-01-01

    Roč. 37, - (2006), s. 210-217 ISSN 1079-9796 R&D Projects: GA MZd NL7681 Institutional research plan: CEZ:AV0Z50200510 Keywords : k562 * cell cycle * hemoglobin synthesis Subject RIV: EE - Microbiology, Virology Impact factor: 2.678, year: 2006

  1. Expression of human gamma-globin genes in human erythroleukemia (K562) cells.

    Science.gov (United States)

    Donovan-Peluso, M; Acuto, S; Swanson, M; Dobkin, C; Bank, A

    1987-12-15

    K562 cells express embryonic (epsilon) and fetal (gamma) globins and hemoglobins but not adult (beta) globin. To define the cis acting regulatory elements involved in the discrimination between gamma and beta genes, we have constructed chimeric genes composed of portions of gamma and beta and evaluated their expression in stable K562 transfectants. A gamma beta fusion gene containing gamma 5' sequences to the EcoRI site in exon 3 and beta sequences 3' is expressed at 10-40% that of the endogenous gamma level. In 50% of the lines, this fusion gene appropriately increases its expression in response to hemin, an inducer of endogenous globin gene expression in K562 cells. In contrast, a beta gamma fusion gene, containing beta sequences 5' to the EcoRI site in exon 3 and gamma sequences 3', is neither expressed nor correctly initiated. A beta gene containing gamma-intervening sequence (IVS) 2 accumulates an mRNA transcript when analyzed with a 3' beta probe. However, no correctly initiated beta mRNA is observed. A gamma gene with beta-IVS 2 is only inducible in one of six expressing clones. All the results are consistent with the presence of stage-specific trans acting factors in K562 cells that stimulate expression of gamma genes and suggest a significant role for gamma-IVS 2 in gamma gene expression.

  2. H-ferritin-regulated microRNAs modulate gene expression in K562 cells.

    Directory of Open Access Journals (Sweden)

    Flavia Biamonte

    Full Text Available In a previous study, we showed that the silencing of the heavy subunit (FHC offerritin, the central iron storage molecule in the cell, is accompanied by a modification in global gene expression. In this work, we explored whether different FHC amounts might modulate miRNA expression levels in K562 cells and studied the impact of miRNAs in gene expression profile modifications. To this aim, we performed a miRNA-mRNA integrative analysis in K562 silenced for FHC (K562shFHC comparing it with K562 transduced with scrambled RNA (K562shRNA. Four miRNAs, namely hsa-let-7g, hsa-let-7f, hsa-let-7i and hsa-miR-125b, were significantly up-regulated in silenced cells. The remarkable down-regulation of these miRNAs, following FHC expression rescue, supports a specific relation between FHC silencing and miRNA-modulation. The integration of target predictions with miRNA and gene expression profiles led to the identification of a regulatory network which includes the miRNAs up-regulated by FHC silencing, as well as91 down-regulated putative target genes. These genes were further classified in 9 networks; the highest scoring network, "Cell Death and Survival, Hematological System Development and Function, Hematopoiesis", is composed by 18 focus molecules including RAF1 and ERK1/2. We confirmed that, following FHC silencing, ERK1/2 phosphorylation is severely impaired and that RAF1 mRNA is significantly down-regulated. Taken all together, our data indicate that, in our experimental model, FHC silencing may affect RAF1/pERK1/2 levels through the modulation of a specific set of miRNAs and add new insights in to the relationship among iron homeostasis and miRNAs.

  3. Radiation-induced apoptosis in differentially modulated by PTK inhibitora in K562 cells

    International Nuclear Information System (INIS)

    Lee, Hyung Sik; Moon, Chang Woo; Hur, Won Joo; Jeong, Su Jin; Jeong Min Ho; Lee, Jeong Hyeon; Lim, Young Jin; Park, Heon Joo

    2000-01-01

    The effect of PTK inhibitors (herbimycin A and genistein) on the induction of radiation-induced apoptosis in Ph-positive K562 leukemia cell line was investigated. K562 cells in exponential growth phase were irradiated with a linear accelerator at room temperature. For 6 MV X-ray irradiation and drug treatment, cultures were initiated at 2x10 6 cells/ml. The cells were irradiated with 10Gy. Stock solutions of herbimycin A and genistein were prepared in dimethyl sulphoxide (DMSO). After incubation at 37 .deg. for 0-48 h, the extent of apoptosis was determined using agarose gel electrophoresis and TUNEL assay. The progression of cells through the cell cycle after irradiation and drug treatment was also determined with flow cytometry. Western blot analysis was used to monitor bcl-2, bcl-X-L and bax protein levels. Treatment with 10 Gy X-irradiation did not result in the induction of apoptosis. The HMA alone (500 nM) also failed to induce apoptosis. By contrast, incubation of K562 cells with HMA after irradiation resulted in a substantial induction of nuclear condensation and fragmentation by agarose gel electrophoresis and TUNEL assay. Genistein failed to enhance the ability of X-irradiation to induce DNA fragmentation. Enhancement of apoptosis by HMA was not attributable to downregulation of the bcl-2 or bcl-X-L anti-apoptotic proteins. When the cells were irradiated and maintained with HMA, the percentage of cells in G2/M phase decreased to 30-40% at 48 h. On the other hand, cells exposed to 10 Gy X-irradiation alone or maintained with genistein did not show marked cell cycle redistribution. We have shown that nanomolar concentrations of the PTK inhibitor HMA synergize with X-irradiation in inducing the apoptosis in Ph (+) K562 leukemia cell line. While, genistein, a PTK inhibitor which is not selective for p210 bcr/abl failed to enhance the radiation induced apoptosis in K562 cells. It is unlikely that the ability of HMA to enhance apoptosis in K562 cells is

  4. Regulation of hTERT by BCR-ABL at multiple levels in K562 cells

    International Nuclear Information System (INIS)

    Chai, Juin Hsien; Zhang, Yong; Tan, Wei Han; Chng, Wee Joo; Li, Baojie; Wang, Xueying

    2011-01-01

    The cytogenetic characteristic of Chronic Myeloid Leukemia (CML) is the formation of the Philadelphia chromosome gene product, BCR-ABL. Given that BCR-ABL is the specific target of Gleevec in CML treatment, we investigated the regulation of the catalytic component of telomerase, hTERT, by BCR-ABL at multiple levels in K562 cells. Molecular techniques such as over expression, knockdown, real-time PCR, immunoprecipitation, western blotting, reporter assay, confocal microscopy, telomerase assays and microarray were used to suggest that hTERT expression and activity is modulated by BCR-ABL at multiple levels. Our results suggest that BCR-ABL plays an important role in regulating hTERT in K562 (BCR-ABL positive human leukemia) cells. When Gleevec inhibited the tyrosine kinase activity of BCR-ABL, phosphorylation of hTERT was downregulated, therefore suggesting a positive correlation between BCR-ABL and hTERT. Gleevec treatment inhibited hTERT at mRNA level and significantly reduced telomerase activity (TA) in K562 cells, but not in HL60 or Jurkat cells (BCR-ABL negative cells). We also demonstrated that the transcription factor STAT5a plays a critical role in hTERT gene regulation in K562 cells. Knockdown of STAT5a, but not STAT5b, resulted in a marked downregulation of hTERT mRNA level, TA and hTERT protein level in K562 cells. Furthermore, translocation of hTERT from nucleoli to nucleoplasm was observed in K562 cells induced by Gleevec. Our data reveal that BCR-ABL can regulate TA at multiple levels, including transcription, post-translational level, and proper localization. Thus, suppression of cell growth and induction of apoptosis by Gleevec treatment may be partially due to TA inhibition. Additionally, we have identified STAT5a as critical mediator of the hTERT gene expression in BCR-ABL positive CML cells, suggesting that targeting STAT5a may be a promising therapeutic strategy for BCR-ABL positive CML patients

  5. IBTK Differently Modulates Gene Expression and RNA Splicing in HeLa and K562 Cells

    Directory of Open Access Journals (Sweden)

    Giuseppe Fiume

    2016-11-01

    Full Text Available The IBTK gene encodes the major protein isoform IBTKα that was recently characterized as substrate receptor of Cul3-dependent E3 ligase, regulating ubiquitination coupled to proteasomal degradation of Pdcd4, an inhibitor of translation. Due to the presence of Ankyrin-BTB-RCC1 domains that mediate several protein-protein interactions, IBTKα could exert expanded regulatory roles, including interaction with transcription regulators. To verify the effects of IBTKα on gene expression, we analyzed HeLa and K562 cell transcriptomes by RNA-Sequencing before and after IBTK knock-down by shRNA transduction. In HeLa cells, 1285 (2.03% of 63,128 mapped transcripts were differentially expressed in IBTK-shRNA-transduced cells, as compared to cells treated with control-shRNA, with 587 upregulated (45.7% and 698 downregulated (54.3% RNAs. In K562 cells, 1959 (3.1% of 63128 mapped RNAs were differentially expressed in IBTK-shRNA-transduced cells, including 1053 upregulated (53.7% and 906 downregulated (46.3%. Only 137 transcripts (0.22% were commonly deregulated by IBTK silencing in both HeLa and K562 cells, indicating that most IBTKα effects on gene expression are cell type-specific. Based on gene ontology classification, the genes responsive to IBTK are involved in different biological processes, including in particular chromatin and nucleosomal organization, gene expression regulation, and cellular traffic and migration. In addition, IBTK RNA interference affected RNA maturation in both cell lines, as shown by the evidence of alternative 3′- and 5′-splicing, mutually exclusive exons, retained introns, and skipped exons. Altogether, these results indicate that IBTK differently modulates gene expression and RNA splicing in HeLa and K562 cells, demonstrating a novel biological role of this protein.

  6. IBTK Differently Modulates Gene Expression and RNA Splicing in HeLa and K562 Cells.

    Science.gov (United States)

    Fiume, Giuseppe; Scialdone, Annarita; Rizzo, Francesca; De Filippo, Maria Rosaria; Laudanna, Carmelo; Albano, Francesco; Golino, Gaetanina; Vecchio, Eleonora; Pontoriero, Marilena; Mimmi, Selena; Ceglia, Simona; Pisano, Antonio; Iaccino, Enrico; Palmieri, Camillo; Paduano, Sergio; Viglietto, Giuseppe; Weisz, Alessandro; Scala, Giuseppe; Quinto, Ileana

    2016-11-07

    The IBTK gene encodes the major protein isoform IBTKα that was recently characterized as substrate receptor of Cul3-dependent E3 ligase, regulating ubiquitination coupled to proteasomal degradation of Pdcd4, an inhibitor of translation. Due to the presence of Ankyrin-BTB-RCC1 domains that mediate several protein-protein interactions, IBTKα could exert expanded regulatory roles, including interaction with transcription regulators. To verify the effects of IBTKα on gene expression, we analyzed HeLa and K562 cell transcriptomes by RNA-Sequencing before and after IBTK knock-down by shRNA transduction. In HeLa cells, 1285 (2.03%) of 63,128 mapped transcripts were differentially expressed in IBTK -shRNA-transduced cells, as compared to cells treated with control-shRNA, with 587 upregulated (45.7%) and 698 downregulated (54.3%) RNAs. In K562 cells, 1959 (3.1%) of 63128 mapped RNAs were differentially expressed in IBTK -shRNA-transduced cells, including 1053 upregulated (53.7%) and 906 downregulated (46.3%). Only 137 transcripts (0.22%) were commonly deregulated by IBTK silencing in both HeLa and K562 cells, indicating that most IBTKα effects on gene expression are cell type-specific. Based on gene ontology classification, the genes responsive to IBTK are involved in different biological processes, including in particular chromatin and nucleosomal organization, gene expression regulation, and cellular traffic and migration. In addition, IBTK RNA interference affected RNA maturation in both cell lines, as shown by the evidence of alternative 3'- and 5'-splicing, mutually exclusive exons, retained introns, and skipped exons. Altogether, these results indicate that IBTK differently modulates gene expression and RNA splicing in HeLa and K562 cells, demonstrating a novel biological role of this protein.

  7. [Effects of Aptamer-siRNA Nucleic Acid Compound on Growth and Apoptosis in Myeloid Leukemia Cell Line K562].

    Science.gov (United States)

    Ping, Juan; Shen, Zhi-Hui; Wang, Bao-Quan; Zhao, Na; Li, Rui; Li, Mian; Pang, Xiao-Bin; Chen, Chuan-Bo

    2015-04-01

    To explore the effects of aptamer-siRNA nucleic acid compound on growth and apoptosis in myeloid leukemia cell line K562. the changes of cellular morphology and structure were observed by using fluorescence microscope, laser confocal microscope, JEM-4000EX transmission electron microscopy; MTT assay were performed to evaluate the sensibility of K562 cells to aptamer-siRNA compound, the apoptosis was detected by DNA gel electro-phoresis. The remarkably changes of morphology and structure of K562 cells treated with 200 µmol/L aptamer-siRNA were observed under fluorescence microscopy and electromicroscopy. As compared with control, the aptamer-siRNA compound showed more inhibitory effect on K562 cells and there was significant difference (Pcompound for K562 cells was 150 µmol/L. According to agarose gel electrophoresis observation, when the aptamer-siRNA compound showed effect on K562 cells, the typical DNA lader could be observed. The aptamer-siRNA compound can significantly induce K562 cell apoptosis, and provide reference for gene therapy of patients with chronic myelocytic lenkemia.

  8. Regulation of HtrA2 on WT1 gene expression under imatinib stimulation and its effects on the cell biology of K562 cells.

    Science.gov (United States)

    Zhang, Lixia; Li, Yan; Li, Xiaoyan; Zhang, Qing; Qiu, Shaowei; Zhang, Qi; Wang, Min; Xing, Haiyan; Rao, Qing; Tian, Zheng; Tang, Kejing; Wang, Jianxiang; Mi, Yingchang

    2017-09-01

    The aim of the present study was to investigate the regulation of Wilms Tumor 1 (WT1) by serine protease high-temperature requirement protein A2 (HtrA2), a member of the Htr family, in K562 cells. In addition, the study aimed to observe the effect of this regulation on cell biological functions and its associated mechanisms. Expression of WT1 and HtrA2 mRNA, and proteins following imatinib and the HtrA2 inhibitor 5-[5-(2-nitrophenyl) furfuryl iodine]-1, 3-diphenyl-2-thiobarbituric acid (UCF-101) treatment was detected with reverse transcription-quantitative polymerase chain reaction and western blot analysis. Subsequent to treatment with drugs and UCF-101, the proliferative function of K562 cells was detected using MTT assays, and the rate of apoptosis was detected using Annexin V with propidium iodide flow cytometry in K562 cells. The protein levels in the signaling pathway were analyzed using western blotting following treatment with imatinib and UCF-101. In K562 cells, imatinib treatment activated HtrA2 gene at a transcription level, while the WT1 gene was simultaneously downregulated. Following HtrA2 inhibitor (UCF-101) treatment, the downregulation of WT1 increased gradually. At the protein level, imatinib induced the increase in HtrA2 protein level and concomitantly downregulated WT1 protein level. Subsequent to HtrA2 inhibition by UCF-101, the WT1 protein level decreased temporarily, but eventually increased. Imatinib induced apoptosis in K562 cells, but this effect was attenuated by the HtrA2 inhibitor UCF-101, resulting in the upregulation of the WT1 protein level. However; UCF-101 did not markedly change the proliferation inhibition caused by imatinib. Imatinib activated the p38 mitogen activated protein kinase (p38 MAPK) signaling pathway in K562 cells, and UCF-101 affected the activation of imatinib in the p38 MAPK signaling pathway. Imatinib inhibited the extracellular signal-related kinase (ERK1/2) pathway markedly and persistently, but UCF-101

  9. The role of catechol-O-methyltransferase in catechol-enhanced erythroid differentiation of K562 cells

    International Nuclear Information System (INIS)

    Suriguga,; Li, Xiao-Fei; Li, Yang; Yu, Chun-Hong; Li, Yi-Ran; Yi, Zong-Chun

    2013-01-01

    Catechol is widely used in pharmaceutical and chemical industries. Catechol is also one of phenolic metabolites of benzene in vivo. Our previous study showed that catechol improved erythroid differentiation potency of K562 cells, which was associated with decreased DNA methylation in erythroid specific genes. Catechol is a substrate for the catechol-O-methyltransferase (COMT)-mediated methylation. In the present study, the role of COMT in catechol-enhanced erythroid differentiation of K562 cells was investigated. Benzidine staining showed that exposure to catechol enhanced hemin-induced hemoglobin accumulation and induced mRNA expression of erythroid specific genes in K562 cells. Treatment with catechol caused a time- and concentration-dependent increase in guaiacol concentration in the medium of cultured K562 cells. When COMT expression was knocked down by COMT shRNA expression in K562 cells, the production of guaiacol significantly reduced, and the sensitivity of K562 cells to cytotoxicity of catechol significantly increased. Knockdown of COMT expression by COMT shRNA expression also eliminated catechol-enhanced erythroid differentiation of K562 cells. In addition, the pre-treatment with methyl donor S-adenosyl-L-methionine or its demethylated product S-adenosyl-L-homocysteine induced a significant increase in hemin-induced Hb synthesis in K562 cells and the mRNA expression of erythroid specific genes. These findings indicated that O-methylation catalyzed by COMT acted as detoxication of catechol and involved in catechol-enhanced erythroid differentiation of K562 cells, and the production of S-adenosyl-L-homocysteine partly explained catechol-enhanced erythroid differentiation. - Highlights: • Catechol enhanced hemin-induced hemoglobin accumulation. • COMT-catalyzed methylation acted as detoxication of catechol. • COMT involved in catechol-enhanced erythroid differentiation

  10. The role of catechol-O-methyltransferase in catechol-enhanced erythroid differentiation of K562 cells

    Energy Technology Data Exchange (ETDEWEB)

    Suriguga,; Li, Xiao-Fei; Li, Yang; Yu, Chun-Hong; Li, Yi-Ran; Yi, Zong-Chun, E-mail: yizc@buaa.edu.cn

    2013-12-15

    Catechol is widely used in pharmaceutical and chemical industries. Catechol is also one of phenolic metabolites of benzene in vivo. Our previous study showed that catechol improved erythroid differentiation potency of K562 cells, which was associated with decreased DNA methylation in erythroid specific genes. Catechol is a substrate for the catechol-O-methyltransferase (COMT)-mediated methylation. In the present study, the role of COMT in catechol-enhanced erythroid differentiation of K562 cells was investigated. Benzidine staining showed that exposure to catechol enhanced hemin-induced hemoglobin accumulation and induced mRNA expression of erythroid specific genes in K562 cells. Treatment with catechol caused a time- and concentration-dependent increase in guaiacol concentration in the medium of cultured K562 cells. When COMT expression was knocked down by COMT shRNA expression in K562 cells, the production of guaiacol significantly reduced, and the sensitivity of K562 cells to cytotoxicity of catechol significantly increased. Knockdown of COMT expression by COMT shRNA expression also eliminated catechol-enhanced erythroid differentiation of K562 cells. In addition, the pre-treatment with methyl donor S-adenosyl-L-methionine or its demethylated product S-adenosyl-L-homocysteine induced a significant increase in hemin-induced Hb synthesis in K562 cells and the mRNA expression of erythroid specific genes. These findings indicated that O-methylation catalyzed by COMT acted as detoxication of catechol and involved in catechol-enhanced erythroid differentiation of K562 cells, and the production of S-adenosyl-L-homocysteine partly explained catechol-enhanced erythroid differentiation. - Highlights: • Catechol enhanced hemin-induced hemoglobin accumulation. • COMT-catalyzed methylation acted as detoxication of catechol. • COMT involved in catechol-enhanced erythroid differentiation.

  11. The role of catechol-O-methyltransferase in catechol-enhanced erythroid differentiation of K562 cells.

    Science.gov (United States)

    Suriguga; Li, Xiao-Fei; Li, Yang; Yu, Chun-Hong; Li, Yi-Ran; Yi, Zong-Chun

    2013-12-15

    Catechol is widely used in pharmaceutical and chemical industries. Catechol is also one of phenolic metabolites of benzene in vivo. Our previous study showed that catechol improved erythroid differentiation potency of K562 cells, which was associated with decreased DNA methylation in erythroid specific genes. Catechol is a substrate for the catechol-O-methyltransferase (COMT)-mediated methylation. In the present study, the role of COMT in catechol-enhanced erythroid differentiation of K562 cells was investigated. Benzidine staining showed that exposure to catechol enhanced hemin-induced hemoglobin accumulation and induced mRNA expression of erythroid specific genes in K562 cells. Treatment with catechol caused a time- and concentration-dependent increase in guaiacol concentration in the medium of cultured K562 cells. When COMT expression was knocked down by COMT shRNA expression in K562 cells, the production of guaiacol significantly reduced, and the sensitivity of K562 cells to cytotoxicity of catechol significantly increased. Knockdown of COMT expression by COMT shRNA expression also eliminated catechol-enhanced erythroid differentiation of K562 cells. In addition, the pre-treatment with methyl donor S-adenosyl-L-methionine or its demethylated product S-adenosyl-L-homocysteine induced a significant increase in hemin-induced Hb synthesis in K562 cells and the mRNA expression of erythroid specific genes. These findings indicated that O-methylation catalyzed by COMT acted as detoxication of catechol and involved in catechol-enhanced erythroid differentiation of K562 cells, and the production of S-adenosyl-L-homocysteine partly explained catechol-enhanced erythroid differentiation. © 2013.

  12. The Effects of Royal Jelly on In-Vitro Cytotoxicity of K562 Cells and Peripheral Blood Mononuclear Cells

    Directory of Open Access Journals (Sweden)

    SE Hosseini

    2014-02-01

    Full Text Available Abstract Background & aim: Royal jelly, secreted by worker bees, has different biological activities on cells and tissues. The aim of this study was to evaluate the effects of royal jelly on peripheral blood mononuclear cells and on the tumor category of K562 cell line. Methods: In the present experimental study, three subjects were selected separately with three repetitions. K562 (104 cells and PBMC (105 cells with different concentrations of royal jelly (5, 10, 25, 50 and 100 mg/ml were cultured under standard conditions for 48 and 72 h separately. The fatality rate on PBMC cells and K562 cancer cells was evaluated by using MTT (Tetrazolium Dye-Reduction Assay. The number of viable cells in PBMC that were exposed for 48 hours with Royal Jelly was evaluated by trypan blue staining. Data were analyzed by ANOVA. Results: The royal jelly had no cytotoxicity effect on PBMC cells but at concentration of 50 and 100 mg/mL the cytotoxicity effect were observed on k562 cells whereas, at 10 and 25 mg/ml the number of PBMC viable cells increased. Conclusion: Due to the lack of lethality of royal jelly on PBMC cells and PBMC cell viability and an increase in the fatality rate of cancer cells in the future, royal jelly can be used as a potential candidate for treatment of leukemia. Keywords: Royal jelly, K562, peripheral blood mononuclear cell

  13. Macrophage inflammatory protein-3α influences growth of K562 leukemia cells in co-culture with anticancer drug-pretreated HS-5 stromal cells

    International Nuclear Information System (INIS)

    Lee, Y.C.; Chiou, T.-J.; Tzeng, W.-F.; Chu, S.T.

    2008-01-01

    Stromal cell monolayers have been an important means of studying the regulation of hematopoiesis, because they produce cytokines. Cytosine arabinoside, vincristine, daunorubicin, and doxorubicin are common drugs for hematological cancer therapy, and they may have some effects on bone marrow stroma during chemotherapy. The aim of this study was to elucidate interactions between the bone marrow stromal microenvironment and leukemic cells after drug treatment. We tested the hypothesis that human HS-5 stromal cells, pretreated with anticancer drugs, affected the growth of leukemic K562 cells by changing the cytokines in the culture microenvironment. Thereafter, proliferation of K562 cells increased nearly 2.5-fold compared the co-cultivation with drugs-pretreated HS-5 stromal cells and drugs-untreated HS-5 stromal cells. The results indicated that co-cultivation with HS-5 stromal cells pretreated with drugs caused significant K562 cell proliferation. Cytokines in the microenvironment were detected via the RayBio Human Cytokine Antibody Array Membrane. The levels of the cytokines CKβ, IL-12, IL-13, IGFBP-2, MCP-1, MCP-3, MCP-4, MDC, MIP-1β and MIP-1δ were decreased, with a particularly marked decrease in MIP-3α. In co-culture medium, there was a 20-fold decrease in MIP-3α in daunorubicin-pretreated HS-5 cells and at least a 3-fold decrease in Ara-C-pretreated cells. This indicated a significant effect of anticancer drugs on the stromal cell line. Using phosphorylated Erk and pRb proteins as cell proliferation markers, we found that phosphorylation of these markers in K562 cells was inhibited during co-cultivation with drug-pretreated stromal cells in MIP-3α-supplemented medium and restored by MIP-3α antibody supplement. In conclusion, anticancer drug pretreatment suppresses the negative control exerted by HS-5 cells on leukemic cell proliferation, via modulation of cytokines in the microenvironment, especially at the level of MIP-3α

  14. Anticancer activity of Pupalia lappacea on chronic myeloid leukemia K562 cells.

    Science.gov (United States)

    Ravi, Alvala; Alvala, Mallika; Sama, Venkatesh; Kalle, Arunasree M; Irlapati, Vamshi K; Reddy, B Madhava

    2012-12-05

    Cancer is one of the most prominent human diseases which has enthused scientific and commercial interest in the discovery of newer anticancer agents from natural sources. Here we demonstrated the anticancer activity of ethanolic extract of aerial parts of Pupalia lappacea (L) Juss (Amaranthaceae) (EAPL) on Chronic Myeloid Leukemia K562 cells. Antiproliferative activity of EAPL was determined by MTT assay using carvacrol as a positive control. Induction of apoptosis was studied by annexin V, mitochondrial membrane potential, caspase activation and cell cycle analysis using flow cytometer and modulation in protein levels of p53, PCNA, Bax and Bcl2 ratio, cytochrome c and cleavage of PARP were studied by Western blot analysis. The standardization of the extract was performed through reverse phase-HPLC using Rutin as biomarker. The results showed dose dependent decrease in growth of K562 cells with an IC50 of 40 ± 0.01 μg/ml by EAPL. Induction of apoptosis by EAPL was dose dependent with the activation of p53, inhibition of PCNA, decrease in Bcl2/Bax ratio, decrease in the mitochondrial membrane potential resulting in release of cytochrome c, activation of multicaspase and cleavage of PARP. Further HPLC standardization of EAPL showed presence 0.024% of Rutin. Present study significantly demonstrates anticancer activity of EAPL on Chronic Myeloid Leukemia (K562) cells which can lead to potential therapeutic agent in treating cancer. Rutin, a known anti cancer compound is being reported and quantified for the first time from EAPL.

  15. Unravelling pathways downstream Sox6 induction in K562 erythroid cells by proteomic analysis

    KAUST Repository

    Barbarani, Gloria

    2017-10-20

    The Sox6 transcription factor is crucial for terminal maturation of definitive red blood cells. Sox6-null mouse fetuses present misshapen and nucleated erythrocytes, due to impaired actin assembly and cytoskeleton stability. These defects are accompanied with a reduced survival of Sox6-/- red blood cells, resulting in a compensated anemia. Sox6-overexpression in K562cells and in human primary ex vivo erythroid cultures enhances erythroid differentiation and leads to hemoglobinization, the hallmark of erythroid maturation. To obtain an overview on processes downstream to Sox6 expression, we performed a differential proteomic analysis on human erythroid K562cells overexpressing Sox6. Sox6-overexpression induces dysregulation of 64 proteins, involved in cytoskeleton remodeling and in protein synthesis, folding and trafficking, key processes for erythroid maturation. Moreover, 43 out of 64 genes encoding for differentially expressed proteins contain within their proximal regulatory regions sites that are bound by SOX6 according to ENCODE ChIP-seq datasets and are possible direct SOX6 targets. SAR1B, one of the most induced proteins upon Sox6 overexpression, shares a conserved regulatory module, composed by a double SOX6 binding site and a GATA1 consensus, with the adjacent SEC24 A gene. Since both genes encode for COPII components, this element could concur to the coordinated expression of these proteins during erythropoiesis.

  16. c-myb stimulates cell growth by regulation of insulin-like growth factor (IGF) and IGF-binding protein-3 in K562 leukemia cells

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Min-Sun; Kim, Sun-Young; Arunachalam, Sankarganesh [Department of Pediatrics, School of Medicine, Chonbuk National University, Jeonju 561-712 (Korea, Republic of); Hwang, Pyoung-Han [Department of Pediatrics, School of Medicine, Chonbuk National University, Jeonju 561-712 (Korea, Republic of); Research Institute of Clinical Medicine, School of Medicine, Chonbuk National University, Jeonju 561-712 (Korea, Republic of); Yi, Ho-Keun [Department of Biochemistry, School of Dentistry, Chonbuk National University, Jeonju 561-712 (Korea, Republic of); Nam, Sang-Yun [Department of Alternative Therapy, School of Alternative Medicine and Health Science, Jeonju University, Jeonju 561-712 (Korea, Republic of); Lee, Dae-Yeol, E-mail: leedy@chonbuk.ac.kr [Department of Pediatrics, School of Medicine, Chonbuk National University, Jeonju 561-712 (Korea, Republic of); Research Institute of Clinical Medicine, School of Medicine, Chonbuk National University, Jeonju 561-712 (Korea, Republic of)

    2009-07-17

    c-myb plays an important role in the regulation of cell growth and differentiation, and is highly expressed in immature hematopoietic cells. The human chronic myelogenous leukemia cell K562, highly expresses IGF-I, IGF-II, IGF-IR, and IGF-induced cellular proliferation is mediated by IGF-IR. To characterize the impact of c-myb on the IGF-IGFBP-3 axis in leukemia cells, we overexpressed c-myb using an adenovirus gene transfer system in K562 cells. The overexpression of c-myb induced cell proliferation, compared to control, and c-myb induced cell growth was inhibited by anti-IGF-IR antibodies. c-myb overexpression resulted in a significant increase in the expression of IGF-I, IGF-II, and IGF-IR, and a decrease in IGFBP-3 expression. By contrast, disruption of c-myb function by DN-myb overexpression resulted in significant reduction of IGF-I, IGF-II, IGF-IR, and elevation of IGFBP-3 expression. In addition, exogenous IGFBP-3 inhibited the proliferation of K562 cells, and c-myb induced cell growth was blocked by IGFBP-3 overexpression in a dose-dependent manner. The growth-promoting effects of c-myb were mediated through two major intracellular signaling pathways, Akt and Erk. Activation of Akt and Erk by c-myb was completely blocked by IGF-IR and IGFBP-3 antibodies. These findings suggest that c-myb stimulates cell growth, in part, by regulating expression of the components of IGF-IGFBP axis in K562 cells. In addition, disruption of c-myb function by DN-myb may provide a useful strategy for treatment of leukemia.

  17. c-myb stimulates cell growth by regulation of insulin-like growth factor (IGF) and IGF-binding protein-3 in K562 leukemia cells

    International Nuclear Information System (INIS)

    Kim, Min-Sun; Kim, Sun-Young; Arunachalam, Sankarganesh; Hwang, Pyoung-Han; Yi, Ho-Keun; Nam, Sang-Yun; Lee, Dae-Yeol

    2009-01-01

    c-myb plays an important role in the regulation of cell growth and differentiation, and is highly expressed in immature hematopoietic cells. The human chronic myelogenous leukemia cell K562, highly expresses IGF-I, IGF-II, IGF-IR, and IGF-induced cellular proliferation is mediated by IGF-IR. To characterize the impact of c-myb on the IGF-IGFBP-3 axis in leukemia cells, we overexpressed c-myb using an adenovirus gene transfer system in K562 cells. The overexpression of c-myb induced cell proliferation, compared to control, and c-myb induced cell growth was inhibited by anti-IGF-IR antibodies. c-myb overexpression resulted in a significant increase in the expression of IGF-I, IGF-II, and IGF-IR, and a decrease in IGFBP-3 expression. By contrast, disruption of c-myb function by DN-myb overexpression resulted in significant reduction of IGF-I, IGF-II, IGF-IR, and elevation of IGFBP-3 expression. In addition, exogenous IGFBP-3 inhibited the proliferation of K562 cells, and c-myb induced cell growth was blocked by IGFBP-3 overexpression in a dose-dependent manner. The growth-promoting effects of c-myb were mediated through two major intracellular signaling pathways, Akt and Erk. Activation of Akt and Erk by c-myb was completely blocked by IGF-IR and IGFBP-3 antibodies. These findings suggest that c-myb stimulates cell growth, in part, by regulating expression of the components of IGF-IGFBP axis in K562 cells. In addition, disruption of c-myb function by DN-myb may provide a useful strategy for treatment of leukemia.

  18. Modulation of P-glycoprotein-mediated multidrug resistance in K562 leukemic cells by indole-3-carbinol

    International Nuclear Information System (INIS)

    Arora, Annu; Seth, Kavita; Kalra, Neetu; Shukla, Yogeshwer

    2005-01-01

    Resistance to chemotherapeutic drugs is one of the major problems in the treatment of cancer. P-glycoprotein (P-gp) encoded by the mdr gene is a highly conserved protein, acts as a multidrug transporter, and has a major role in multiple drug resistance (MDR). Targeting of P-gp by naturally occurring compounds is an effective strategy to overcome MDR. Indole-3-carbinol (I3C), a glucosinolates present in cruciferous vegetables, is a promising chemopreventive agent as it is reported to possess antimutagenic, antitumorigenic, and antiestrogenic properties in experimental studies. In the present investigation, the potential of I3C to modulate P-gp expression was evaluated in vinblastine (VBL)-resistant K562 human leukemic cells. The resistant K562 cells (K562/R10) were found to be cross-resistant to vincristine (VCR), doxorubicin (DXR), and other antineoplastic agents. I3C at a nontoxic dose (10 x 10 -3 M) enhanced the cytotoxic effects of VBL time dependently in VBL-resistant human leukemia (K562/R10) cells but had no effect on parent-sensitive cells (K562/S). The Western blot analysis of K 562/R 10 cells showed that I3C downregulates the induced levels of P-gp in resistant cells near to normal levels. The quantitation of immunocytochemically stained K562/R10 cells showed 24%, 48%, and 80% decrease in the levels of P-gp by I3C for 24, 48, and 72 h of incubation. The above features thus indicate that I3C could be used as a novel modulator of P-gp-mediated multidrug resistance in vitro and may be effective as a dietary adjuvant in the treatment of MDR cancers

  19. Inhibitory effect of PTD-OD-HA fusion protein on Bcr-Abl in K562 cells

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    Miao GAO

    2012-10-01

    Full Text Available Objective To study the transduction dynamics, location of PTD-OD-HA fusion protein and its interaction with Bcr-Abl oncoprotein in K562 cell lines, and explore the influence of PTD-OD-HA fusion protein on oligomerization and tyrosine kinase activity of Bcr-Abl. Methods PTD-OD-HA fusion protein was labeled with FITC and co-cultured with K562 cells. The transduction efficiency of labeled PTD-OD-HA at different doses and time intervals was observed under fluorescence microscope. The location of labeled PTD-OD-HA fusion protein in K562 cells was detected by confocal microscopy. The interaction of PTD-OD-HA fusion protein with Bcr-Abl oncoprotein was confirmed by coimmunoprecipitation. The phosphorylation of Bcr-Abl oncoprotein was detected by Western blotting. Results PTD-OD-HA fusion protein labeled with FITC was transduced into K562 cells in a dose- and time-dependent manner. PTD-OD-HA fusion protein was located in the cytoplasm of K562 cells and was consistent with the location of Bcr-Abl oncoprotein. The interaction of PTD-OD-HA fusion protein with Bcr-Abl oncoprotein was proved in K562 cells. This interaction could interrupt the homologous oligomerization of Bcr-Abl oncoprotein and reduce the phosphorylation of Bcr-Abl oncoprotein. Conclusion PTD-OD-HA fusion protein could be transduced into K562 cells efficiently, inhibit the oligomerization and reduce the phosphorylation of Bcr-Abl oncoprotein.

  20. Comparison of different methods for erythroid differentiation in the K562 cell line.

    Science.gov (United States)

    Shariati, Laleh; Modaress, Mehran; Khanahmad, Hossein; Hejazi, Zahra; Tabatabaiefar, Mohammad Amin; Salehi, Mansoor; Modarressi, Mohammad Hossein

    2016-08-01

    To compare methods for erythroid differentiation of K562 cells that will be promising in the treatment of beta-thalassemia by inducing γ-globin synthesis. Cells were treated separately with: RPMI 1640 medium without glutamine, RPMI 1640 medium without glutamine supplemented with 1 mM sodium butyrate, RPMI 1640 medium supplemented with 1 mM sodium butyrate, 25 µg cisplatin/ml, 0.1 µg cytosine arabinoside/ml. The highest differentiation (84 %) with minimum toxicity was obtained with cisplatin at 15 µg /ml. Real-time RT-PCR showed that expression of the γ-globin gene was significantly higher in the cells differentiated with cisplatin compared to undifferentiated cells (P < 0.001). Cisplatin is useful in the experimental therapy of ß-globin gene defects and can be considered for examining the basic mechanism of γ-reactivation.

  1. Inhibitiory properties of cytoplasmic extract of Lactobacilli isolated from common carp intestine on human chronic myelocytic leukemia K562 cell line: an in vitro study

    Directory of Open Access Journals (Sweden)

    Kabiri F

    2011-03-01

    Full Text Available "n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 st1":*{behavior:url(#ieooui } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: Lactobacillus species are genetically diverse groups of Lactic Acid Bacteria (LAB that have been introduced as probiotics, because of some characteristics such as their anti-tumor properties, helping the intestinal flora balance, production of antibiotics, stimulation of host immune response, etc. The aim of this study was to investigate the effects of cytoplasmic extraction and cell wall of Lactobacillus species isolated from the intestine of common carp on human chronic myelocytic leukemia or K562 cancer cell lines."n"nMethods: The intestinal contents of 115 common carp captured from the natural resources of West Azerbaijan province in Iran were examined for LAB. After isolation, the identification of Lactobacilli was done according to traditional and molecular bacteriological tests. Subsequently, a suspension of each bacterium was prepared and the protein content of the cytoplasm was extracted. Cell wall disintegration was done by cell lysis buffer and sonication. The effects of cytoplasmic extraction and cell wall on K562 cell line proliferation were investigated by MTT assays."n"nResults: The cytoplasmic extraction of the isolated Lactobacilli had significant (p<0.05 anti

  2. Aqueous extract of Crataegus azarolus protects against DNA damage in human lymphoblast Cell K562 and enhances antioxidant activity.

    Science.gov (United States)

    Mustapha, Nadia; Bouhlel, Inès; Chaabane, Fadwa; Bzéouich, Imèn Mokdad; Ghedira, Kamel; Hennebelle, Thierry; Chekir-Ghedira, Leila

    2014-02-01

    The present study was carried out to characterize the cellular antioxidant effect of the aqueous extract of Crataegus azarolus and its antigenotoxic potential using human myelogenous cells, K562. The antioxidant capacity of this extract was evaluated by determining its cellular antioxidant activity (CAA) in K562 cells. Also, preceding antigenotoxicity assessment, its eventual genotoxicity property was investigated by evaluating its capacity to induce the DNA degradation of treated cell nuclei. As no genotoxicity was detected at different exposure times, its ability to protect cell DNA against H2O2 oxidative effect was investigated, using the "comet assay." It appears that 800 μg/mL of extract inhibited the genotoxicity induced by H2O2 with a rate of 41.30 %, after 4 h of incubation. In addition, this extract revealed a significant cellular antioxidant capacity against the reactive oxygen species in K562 cells.

  3. 6′-Hydroxy Justicidin B Triggers a Critical Imbalance in Ca2+ Homeostasis and Mitochondrion-Dependent Cell Death in Human Leukemia K562 Cells

    Directory of Open Access Journals (Sweden)

    Jiaoyang Luo

    2018-06-01

    Full Text Available Justicia procumbens (J. procumbens is a traditional Chinese herbal medicine which was used for the treatment of fever, pain, and cancer. A compound 6′-hydroxy justicidin B (HJB isolated from J. procumbens exhibits promising biological properties. However, the mechanism of action and the in vivo behavior of HJB remain to be elucidated. In this study, we investigated the mechanism of action of HJB on human leukemia K562 cells and its pharmacokinetic properties in rats. The results demonstrated that HJB significantly inhibited the proliferation of K562 cells and promoted apoptosis. Besides, HJB resulted in decreased mitochondrial membrane potential deltaPSIm, increased the level of the calcium homeostasis regulator protein TRPC6 and cytosolic calcium. The activity of caspase-8, caspase-9 and the expression of p53 were significantly increased after treatment with HJB. Additionally, HJB has rapid absorption rate and relative long elimination t1/2, indicating a longer residence time in vivo. The results indicate that HJB inhibited the proliferation of K562 cells and induced apoptosis by affecting the function of mitochondria and calcium homeostasis to activate the p53 signaling pathway. The pharmacokinetic study of HJB suggested it is absorbed well and has moderate metabolism in vivo. These results present HJB as a potential novel alternative to standard human leukemia therapies.

  4. Multidrug resistance in tumour cells: characterisation of the multidrug resistant cell line K562-Lucena 1

    Directory of Open Access Journals (Sweden)

    VIVIAN M. RUMJANEK

    2001-03-01

    Full Text Available Multidrug resistance to chemotherapy is a major obstacle in the treatment of cancer patients. The best characterised mechanism responsible for multidrug resistance involves the expression of the MDR-1 gene product, P-glycoprotein. However, the resistance process is multifactorial. Studies of multidrug resistance mechanisms have relied on the analysis of cancer cell lines that have been selected and present cross-reactivity to a broad range of anticancer agents. This work characterises a multidrug resistant cell line, originally selected for resistance to the Vinca alkaloid vincristine and derived from the human erythroleukaemia cell K562. This cell line, named Lucena 1, overexpresses P-glycoprotein and have its resistance reversed by the chemosensitisers verapamil, trifluoperazine and cyclosporins A, D and G. Furthermore, we demonstrated that methylene blue was capable of partially reversing the resistance in this cell line. On the contrary, the use of 5-fluorouracil increased the resistance of Lucena 1. In addition to chemotherapics, Lucena 1 cells were resistant to ultraviolet A radiation and hydrogen peroxide and failed to mobilise intracellular calcium when thapsigargin was used. Changes in the cytoskeleton of this cell line were also observed.A resistência a múltiplos fármacos é o principal obstáculo no tratamento de pacientes com câncer. O mecanismo responsável pela resistência múltipla mais bem caracterizado envolve a expressão do produto do gene MDR-1, a glicoproteína P. Entretanto, o processo de resistência tem fatores múltiplos. Estudos de mecanismos de resistência m��ltipla a fármacos têm dependido da análise de linhagens celulares tumorais que foram selecionadas e apresentam reatividade cruzada a uma ampla faixa de agentes anti-tumorais. Este trabalho caracteriza uma linhagem celular com múltipla resistência a fármacos, selecionada originalmente pela resistência ao alcalóide de Vinca vincristina e derivado

  5. Delayed K562 cell apoptosis promoted by cleaved LyGDI after 60Co γ-rays irradiation

    International Nuclear Information System (INIS)

    Sun Huali; Duan Weiming; Shao Yanyan; Xiao Hainan; Zhou Xinwen

    2010-01-01

    Objective: To elucidate the function and regulatory mechanism of LyGDI involved delayed cell death in the human K562 cells and HL-60 cells induced by 60 Co γ-rays. Methods: Erythrosine B cells staining was used to count the apoptosis rate. PI staining and flow cytometry were applied to check the cell cycle. The expression of LYGDI and Rac1 was resolved by Western blot by using monoclonal antibody of LyGDI and Rac1. The distribution of Rac1 protein in cells was observed with immunofluorescence by using the confocal microscope. Results: The K562 cells showed G 2 /M phase arrest and the percent age was 71.3%. The apoptosis rate was very low at early post-irradiation stage in the K562 cells. The apoptosis rate was 14% in the K562 cells at 24 h post-irradiation with 8 Gy of γ-rays, and delayed cell apoptosis was present. LyGDI was cleaved in the K562 cells irradiated by 4 Gy 60 Co γ-rays after 24 hours post-irradiation. The expression of Rac1 protein was not altered at all, but the distribution was changed in the irradiated cells while the Rac1 protein moved to cell membrane and a little in cell nucleus. The Rac1 was activated with the losing the binding affinity with the LyGDI. Conclusion: LyGDI could promote the delayed cell apoptosis, which is through the activation of the Rac1. (authors)

  6. H ferritin silencing induces protein misfolding in K562 cells: A Raman analysis

    KAUST Repository

    Zolea, Fabiana

    2015-10-09

    The redox state of the cell is involved in the regulation of many physiological functions as well as in the pathogenesis of several diseases, and is strictly dependent on the amount of iron in its catalytically active state. Alterations of iron homeostasis determine increased steady-state concentrations of Reactive Oxygen Species (ROS) that cause lipid peroxidation, DNA damage and altered protein folding. Ferritin keeps the intracellular iron in a non-toxic and readily available form and consequently plays a central role in iron and redox homeostasis. The protein is composed by 24 subunits of the H- and L-type, coded by two different genes, with structural and functional differences. The aim of this study was to shed light on the role of the single H ferritin subunit (FHC) in keeping the native correct protein three-dimensional structure. To this, we performed Raman spectroscopy on protein extracts from K562 cells subjected to FHC silencing. The results show a significant increase in the percentage of disordered structures content at a level comparable to that induced by H2O2 treatment in control cells. ROS inhibitor and iron chelator were able to revert protein misfolding. This integrated approach, involving Raman spectroscopy and targeted-gene silencing, indicates that an imbalance of the heavy-to-light chain ratio in the ferritin composition is able to induce severe but still reversible modifications in protein folding and uncovers new potential pathogenetic mechanisms associated to intracellular iron perturbation.

  7. H ferritin silencing induces protein misfolding in K562 cells: A Raman analysis

    KAUST Repository

    Zolea, Fabiana; Biamonte, Flavia; Candeloro, Patrizio; Di Sanzo, Maddalena; Cozzi, Anna; Di Vito, Anna; Quaresima, Barbara; Lobello, Nadia; Trecroci, Francesca; Di Fabrizio, Enzo M.; Levi, Sonia; Cuda, Giovanni; Costanzo, Francesco

    2015-01-01

    The redox state of the cell is involved in the regulation of many physiological functions as well as in the pathogenesis of several diseases, and is strictly dependent on the amount of iron in its catalytically active state. Alterations of iron homeostasis determine increased steady-state concentrations of Reactive Oxygen Species (ROS) that cause lipid peroxidation, DNA damage and altered protein folding. Ferritin keeps the intracellular iron in a non-toxic and readily available form and consequently plays a central role in iron and redox homeostasis. The protein is composed by 24 subunits of the H- and L-type, coded by two different genes, with structural and functional differences. The aim of this study was to shed light on the role of the single H ferritin subunit (FHC) in keeping the native correct protein three-dimensional structure. To this, we performed Raman spectroscopy on protein extracts from K562 cells subjected to FHC silencing. The results show a significant increase in the percentage of disordered structures content at a level comparable to that induced by H2O2 treatment in control cells. ROS inhibitor and iron chelator were able to revert protein misfolding. This integrated approach, involving Raman spectroscopy and targeted-gene silencing, indicates that an imbalance of the heavy-to-light chain ratio in the ferritin composition is able to induce severe but still reversible modifications in protein folding and uncovers new potential pathogenetic mechanisms associated to intracellular iron perturbation.

  8. Synergistic effect of hydrogen peroxide on polyploidization during the megakaryocytic differentiation of K562 leukemia cells by PMA.

    Science.gov (United States)

    Ojima, Yoshihiro; Duncan, Mark Thompson; Nurhayati, Retno Wahyu; Taya, Masahito; Miller, William Martin

    2013-08-15

    The human myelogenous cell line, K562 has been extensively used as a model for the study of megakaryocytic (MK) differentiation, which could be achieved by exposure to phorbol 12-myristate 13-acetate (PMA). In this study, real-time PCR analysis revealed that the expression of catalase (cat) was significantly repressed during MK differentiation of K562 cells induced by PMA. In addition, PMA increased the intracellular reactive oxygen species (ROS) concentration, suggesting that ROS was a key factor for PMA-induced differentiation. PMA-differentiated K562 cells were exposed to hydrogen peroxide (H2O2) to clarify the function of ROS during MK differentiation. Interestingly, the percentage of high-ploidy (DNA content >4N) cells with H2O2 was 34.8±2.3% at day 9, and was 70% larger than that without H2O2 (21.5±0.8%). Further, H2O2 addition during the first 3 days of PMA-induced MK differentiation had the greatest effect on polyploidization. In an effort to elucidate the mechanisms of enhanced polyploidization by H2O2, the BrdU assay clearly indicated that H2O2 suppressed the division of 4N cells into 2N cells, followed by the increased polyploidization of K562 cells. These findings suggest that the enhancement in polyploidization mediated by H2O2 is due to synergistic inhibition of cytokinesis with PMA. Although H2O2 did not increase ploidy during the MK differentiation of primary cells, we clearly observed that cat expression was repressed in both immature and mature primary MK cells, and that treatment with the antioxidant N-acetylcysteine effectively blocked and/or delayed the polyploidization of immature MK cells. Together, these findings suggest that MK cells are more sensitive to ROS levels during earlier stages of maturation. Copyright © 2013 Elsevier Inc. All rights reserved.

  9. Time-series analysis in imatinib-resistant chronic myeloid leukemia K562-cells under different drug treatments.

    Science.gov (United States)

    Zhao, Yan-Hong; Zhang, Xue-Fang; Zhao, Yan-Qiu; Bai, Fan; Qin, Fan; Sun, Jing; Dong, Ying

    2017-08-01

    Chronic myeloid leukemia (CML) is characterized by the accumulation of active BCR-ABL protein. Imatinib is the first-line treatment of CML; however, many patients are resistant to this drug. In this study, we aimed to compare the differences in expression patterns and functions of time-series genes in imatinib-resistant CML cells under different drug treatments. GSE24946 was downloaded from the GEO database, which included 17 samples of K562-r cells with (n=12) or without drug administration (n=5). Three drug treatment groups were considered for this study: arsenic trioxide (ATO), AMN107, and ATO+AMN107. Each group had one sample at each time point (3, 12, 24, and 48 h). Time-series genes with a ratio of standard deviation/average (coefficient of variation) >0.15 were screened, and their expression patterns were revealed based on Short Time-series Expression Miner (STEM). Then, the functional enrichment analysis of time-series genes in each group was performed using DAVID, and the genes enriched in the top ten functional categories were extracted to detect their expression patterns. Different time-series genes were identified in the three groups, and most of them were enriched in the ribosome and oxidative phosphorylation pathways. Time-series genes in the three treatment groups had different expression patterns and functions. Time-series genes in the ATO group (e.g. CCNA2 and DAB2) were significantly associated with cell adhesion, those in the AMN107 group were related to cellular carbohydrate metabolic process, while those in the ATO+AMN107 group (e.g. AP2M1) were significantly related to cell proliferation and antigen processing. In imatinib-resistant CML cells, ATO could influence genes related to cell adhesion, AMN107 might affect genes involved in cellular carbohydrate metabolism, and the combination therapy might regulate genes involved in cell proliferation.

  10. The best time of cytotoxicity for extracted cell wall from Lactobacillus casei and paracasei in K562 cell line

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    Riki M

    2013-02-01

    Full Text Available Background: The aim of this study was to evaluate the effect of extracted cell walls from Lactobacillus casei and Lactobacillus paracasei as probiotic bacteria (isolated from common carp intestine on K562 and the role of cell concentration on the results of MTT [3-(4,5-Dimethylthiazol-2-yl2,5- Diphenyl tetrazolium Bromide] test.Methods: For this purpose, bacteria were cultured in specific medium (MRS broth at anaerobic condition for 24-48 hour. After incubation period culture medium was centri-fuged, then the cells were washed twice with PBS buffer to remove additional medium. Finally, collected bacterial cell disrupted by Sonication and cell walls were separated from other components by centrifugation. After that, different concentrations of cell walls (500, 1000, 2000 and 4000 µg/ml were prepared in RPMI medium for each bacteria, separately. Then anticancer properties of the cell walls were determined in vitro at 12, 24, 48 and 72 h, also the effect of K562 concentration was assayed with MTT technique.Results: The results showed extracted cell wall from both probiotic statistically (P=0.098 have anti turmeric properties in K562 and their properties will arise in relation with concentration. As well as, we found that the number of cell had not any affect on the result of MTT assay.Conclusion: We conclude that the cytotoxicity property of extracted cell wall is related in the type of bacteria, but this anticancer property would warrant further study on the clinical application of extracted cell wall.

  11. SATB1 regulates SPARC expression in K562 cell line through binding to a specific sequence in the third intron

    International Nuclear Information System (INIS)

    Li, K.; Cai, R.; Dai, B.B.; Zhang, X.Q.; Wang, H.J.; Ge, S.F.; Xu, W.R.; Lu, J.

    2007-01-01

    Special AT-rich binding protein 1 (SATB1), a cell type-specific nuclear matrix attachment region (MAR) DNA-binding protein, tethers to a specific DNA sequence and regulates gene expression through chromatin remodeling and HDAC (histone deacetylase complex) recruitment. In this study, a SATB1 eukaryotic expression plasmid was transfected into the human erythroleukemia K562 cell line and individual clones that stably over-expressed the SATB1 protein were isolated. Microarray analysis revealed that hundreds of genes were either up- or down-regulated in the SATB1 over-expressing K562 cell lines. One of these was the extra-cellular matrix glycoprotein, SPARC (human secreted protein acidic and rich in cysteine). siRNA knock-down of SATB1 also reduced SPARC expression, which was consistent with elevated SPARC levels in the SATB1 over-expressing cell line. Bioinformatics software Mat-inspector showed that a 17 bp DNA sequence in the third intron of SPARC possessed a high potential for SATB1 binding; a finding confirmed by Chromatin immunoprecipitation (ChIP) with anti-SATB1 antibody. Our results show for the first time that forced-expression of SATB1 in K562 cells triggers SPARC up-regulation by binding to a 17 bp DNA sequence in the third intron

  12. Carbon monoxide induced erythroid differentiation of K562 cells mimics the central macrophage milieu in erythroblastic islands.

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    Shlomi Toobiak

    Full Text Available Growing evidence supports the role of erythroblastic islands (EI as microenvironmental niches within bone marrow (BM, where cell-cell attachments are suggested as crucial for erythroid maturation. The inducible form of the enzyme heme oxygenase, HO-1, which conducts heme degradation, is absent in erythroblasts where hemoglobin (Hb is synthesized. Yet, the central macrophage, which retains high HO-1 activity, might be suitable to take over degradation of extra, harmful, Hb heme. Of these enzymatic products, only the hydrophobic gas molecule--CO can transfer from the macrophage to surrounding erythroblasts directly via their tightly attached membranes in the terminal differentiation stage.Based on the above, the study hypothesized CO to have a role in erythroid maturation. Thus, the effect of CO gas as a potential erythroid differentiation inducer on the common model for erythroid progenitors, K562 cells, was explored. Cells were kept under oxygen lacking environment to mimic BM conditions. Nitrogen anaerobic atmosphere (N₂A served as control for CO atmosphere (COA. Under both atmospheres cells proliferation ceased: in N₂A due to cell death, while in COA as a result of erythroid differentiation. Maturation was evaluated by increased glycophorin A expression and Hb concentration. Addition of 1%CO only to N₂A, was adequate for maintaining cell viability. Yet, the average Hb concentration was low as compared to COA. This was validated to be the outcome of diversified maturation stages of the progenitor's population.In fact, the above scenario mimics the in vivo EI conditions, where at any given moment only a minute portion of the progenitors proceeds into terminal differentiation. Hence, this model might provide a basis for further molecular investigations of the EI structure/function relationship.

  13. Effects of the antitumoural dequalinium on NB4 and K562 human leukemia cell lines. Mitochondrial implication in cell death.

    Science.gov (United States)

    Galeano, Eva; Nieto, Elena; García-Pérez, Ana Isabel; Delgado, M Dolores; Pinilla, Montserrat; Sancho, Pilar

    2005-10-01

    Dequalinium (DQA) is a delocalized lipophylic cation that selectively targets the mitochondria of carcinoma cells. However, the underlying mechanisms of DQA action are not yet well understood. We have studied the effects of DQA on two different leukemia cell lines: NB4, derived from acute promyelocytic leukemia, and K562, derived from chronic myeloid leukemia. We found that DQA displays differential cytotoxic activity in these cell lines. In NB4 cells, a low DQA concentration (2microM) induces a mixture of apoptosis and necrosis, whereas a high DQA concentration (20microM) induces mainly necrosis. However, K562 cell death was always by necrosis as the cells showed a resistance to apoptosis at all time-periods and DQA concentrations assayed. In both cell lines, the cell death seems to be mediated by alterations of mitochondrial function as evidenced by loss of mitochondrial transmembrane potential, O2*- accumulation and ATP depletion. The current study improves the knowledge on DQA as a novel anticancer agent with a potential application in human acute promyelocytic leukemia chemotherapy.

  14. PENGARUH EKSTRAK JAMU TERHADAP AKTIVITAS SEL NATURAL KILLER DALAM MELISIS ALUR SEL LEUKIMIA (K-562 SECARA IN VITRO [The Effects of Commercial “Jamu” Extracts on Natural Killer Cell Activity in Lysing Leukemic Cell Line (K-562 in vitro

    Directory of Open Access Journals (Sweden)

    Elisa Veronica D.C. 2

    2002-04-01

    Full Text Available Natural killer (NK cell consitutes white blood cells which specifically functions in lysing tumor and virus invected cells. In this research, a commercial “Jamu” was tested to observe its effect on NK cells activity against leukemic cell lines (K562 in vitro. Jamu was extracted with hot water, diluted and added into cell cultures consisted of a mixture of human peripheric limphocyte cells, as the source of the effector NK cells, and K562 cell line i.e., the target cells which were cell line derived from human leukemia and had been labelled with H3-thymidine. The mixture of the cells were made by culturing the two cells at the ratio of 50:1 and 100 : 1, respectively. The results showed that lysing activity of NK cells in the presence of “Jamu” water extract measured as lysing percentage and lysing index increased only slightly, which were not statiscally significant. It should be considered that the test used in this research represents only a part of the lysing mechanism by NK cells against the target cells. An in vivo test for a period of time will be recessary to elucidate ffurther this NK cell activity.

  15. Small Molecule TH-39 Potentially Targets Hec1/Nek2 Interaction and Exhibits Antitumor Efficacy in K562 Cells via G0/G1 Cell Cycle Arrest and Apoptosis Induction.

    Science.gov (United States)

    Zhu, Yongxia; Wei, Wei; Ye, Tinghong; Liu, Zhihao; Liu, Li; Luo, Yong; Zhang, Lidan; Gao, Chao; Wang, Ningyu; Yu, Luoting

    2016-01-01

    Cancer is still a major public health issue worldwide, and new therapeutics with anti-tumor activity are still urgently needed. The anti-tumor activity of TH-39, which shows potent anti-proliferative activity against K562 cells with an IC50 of 0.78 µM, was investigated using immunoblot, co-immunoprecipitation, the MTT assay, and flow cytometry. Mechanistically, TH-39 may disrupt the interaction between Hec1 and Nek2 in K562 cells. Moreover, TH-39 inhibited cell proliferation in a concentration- and time-dependent manner by influencing the morphology of K562 cells and inducing G0/G1 phase arrest. G0/G1 phase arrest was associated with down-regulation of CDK2-cyclin E complex and CDK4/6-cyclin D complex activities. Furthermore, TH-39 also induced cell apoptosis, which was associated with activation of caspase-3, down-regulation of Bcl-2 expression and up-regulation of Bax. TH-39 could also decrease mitochondrial membrane potential (Δψm) and increase reactive oxygen species (ROS) accumulation in K562 cells. The results indicated that TH-39 might induce apoptosis via the ROS-mitochondrial apoptotic pathway. This study highlights the potential therapeutic efficacy of the anti-cancer compound TH-39 in treatment-resistant chronic myeloid leukemia. © 2016 The Author(s) Published by S. Karger AG, Basel.

  16. Apoptosis induction in MV4-11 and K562 human leukemic cells by Pereskia sacharosa (Cactaceae) leaf crude extract.

    Science.gov (United States)

    Asmaa, Mat Jusoh Siti; Al-Jamal, Hamid Ali Nagi; Ang, Cheng Yong; Asan, Jamaruddin Mat; Seeni, Azman; Johan, Muhammad Farid

    2014-01-01

    Pereskia sacharosa is a genus of cacti widely used in folk medicine for cancer-related treatment. Anti-proliferative effects have been studied in recent years against colon, breast, cervical and lung cancer cell lines, with promising results. We here extended study of anti-proliferative effects to a blood malignancy, leukemia. Two leukemic cell lines, MV4-11 (acute myeloid leukemia) and K562 (chronic myeloid leukemia), were studied. IC50 concentrations were determined and apoptosis and cell cycle regulation were studied by flow cytometric analysis. The expression of apoptosis and cell-cycle related regulatory proteins was assessed by Western blotting. P sacharosa inhibited growth of MV4-11 and K562 cells in a dose-dependent manner. The mode of cell death was via induction of intrinsic apoptotic pathways and cell cycle arrest. There was profound up-regulation of cytochrome c, caspases, p21 and p53 expression and repression of Akt and Bcl-2 expression in treated cells. These results suggest that P sacharosa induces leukemic cell death via apoptosis induction and changes in cell cycle checkpoint, thus deserves further study for anti-leukemic potential.

  17. Phenethyl isothiocyanate inhibits growth of human chronic myeloid leukemia K562 cells via reactive oxygen species generation and caspases.

    Science.gov (United States)

    Wang, Yating; Wei, Sixi; Wang, Jishi; Fang, Qin; Chai, Qixiang

    2014-07-01

    Phenethyl isothiocyanate (PEITC), a potential cancer chemopreventive constituent of cruciferous vegetables, including watercress, has been reported to inhibit cancer cell growth by arresting the cell cycle and inducing apoptosis in various human cancer cell models. However, the role of PEITC in the inhibition of human chronic myeloid leukemia (CML) K562 cell growth and its underlying mechanisms have yet to be elucidated. In the present study, PEITC was found to induce cell death through the induction of reactive oxygen species (ROS) stress and oxidative damage. Heme oxygenase‑1 (HO‑1), which participates in the development of numerous tumors and the sensitivity of these tumors to chemotherapeutic drugs, plays a protective role by modulating oxidative injury. Therefore, the present study assessed the inhibitory effect of PEITC on K562 cells and whether HO‑1 facilitated cell apoptosis and ROS generation. PEITC was found to suppress cell growth and cause apoptosis by promoting Fas and Fas ligand expression, increasing ROS generation and by the successive release of cytochrome c as well as the activation of caspase‑9 and caspase‑3. PEITC was also combined with the HO‑1 inhibitor zinc protoporphyrin IX and the inducer hemin to assess whether HO‑1 determines cell survival and ROS generation. The results of the present study suggest that PEITC may be a potential anti‑tumor compound for CML therapy, and that HO‑1 has a critical function in PEITC‑induced apoptosis and ROS generation.

  18. Nuclear topography of beta-like globin gene cluster in IL-3-stimulated human leukemic K-562 cells

    Czech Academy of Sciences Publication Activity Database

    Galiová-Šustáčková, Gabriela; Bártová, Eva; Kozubek, Stanislav

    2004-01-01

    Roč. 33, č. 1 (2004), s. 4-14 ISSN 1079-9796 R&D Projects: GA ČR GA301/01/0186; GA AV ČR KSK5052113; GA AV ČR IAA5004306; GA ČR GA202/04/0907; GA MŠk ME 565 Institutional research plan: CEZ:AV0Z5004920 Keywords : beta-like globin gene cluster * K-562 cells * nuclear topography Subject RIV: BO - Biophysics Impact factor: 2.549, year: 2004

  19. Comparative Study of Different Nano-Formulations of Curcumin for Reversal of Doxorubicin Resistance in K562R Cells.

    Science.gov (United States)

    Dash, Tapan K; Konkimalla, V Badireenath

    2017-02-01

    Curcumin is very well established as a chemo-therapeutic, chemo-preventive and chemo-sensitizing agent in diverse disease conditions. As the isolated pure form has poor solubility and pharmacokinetic problems, therefore it is encapsulated in to several nano-formulations to improve its bioavailability. Here in the current study, we aim to compare different nano-formulations of curcumin for their chemo-sensitizing activity in doxorubicin (DOX) resistant K562 cells. Four different curcumin formulations were prepared namely DMSO assisted curcumin nano-dispersion (CurD, 260 nm), liposomal curcumin (CurL, 165 nm), MPEG-PCL micellar curcumin (CurM, 18 nm) and cyclodextrin encapsulated curcumin (CurN, 37 nm). The formulations were subjected to particle characterizations (size, zeta potential, release studies), followed by biological assays such as cellular uptake, P-gp inhibitory activity and reversal of DOX resistance by co-treatment with DOX. Curcumin uptake in K562N and K562R cells was mildly reduced when treated with CurL and CurM, while for CurD and CurN the uptake remained equivalent. However, CurL retained P-gp inhibitory activity of curcumin and with a considerable chemo-sensitizing effect but CurM showed no P-gp inhibitory activity. CurN retained above biological activities, but requires a secondary carrier under in vivo conditions. From the results, CurM was found to be most suitable for solubilization of curcumin where as CurL can be considered as most suitable nano-formulation for reversal of DOX resistance.

  20. Chaetominine reduces MRP1-mediated drug resistance via inhibiting PI3K/Akt/Nrf2 signaling pathway in K562/Adr human leukemia cells

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Jingyun; Wei, Xing [State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai (China); Shanghai Collaborative Innovation Center for Biomanufacturing Technology, 130 Meilong Road, Shanghai (China); Lu, Yanhua, E-mail: luyanhua@ecust.edu.cn [State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai (China); Shanghai Collaborative Innovation Center for Biomanufacturing Technology, 130 Meilong Road, Shanghai (China)

    2016-05-13

    Drug resistance limits leukemia treatment and chaetominine, a cytotoxic alkaloid that promotes apoptosis in a K562 human leukemia cell line via the mitochondrial pathway was studied with respect to chemoresistance in a K562/Adr human resistant leukemia cell line. Cytotoxicity assays indicated that K562/Adr resistance to adriamycin (ADR) did not occur in the presence of chaetominine and that chaetominine increased chemosensitivity of K562/Adr to ADR. Data show that chaetominine enhanced ADR-induced apoptosis and intracellular ADR accumulation in K562/Adr cells. Accordingly, chaetominine induced apoptosis by upregulating ROS, pro-apoptotic Bax and downregulating anti-apoptotic Bcl-2. RT-PCR and western-blot confirmed that chaetominine suppressed highly expressed MRP1 at mRNA and protein levels. But little obvious alternation of another drug transporter MDR1 mRNA was observed. Furthermore, inhibition of MRP1 by chaetominine relied on inhibiting Akt phosphorylation and nuclear Nrf2. In summary, chaetominine strongly reverses drug resistance by interfering with the PI3K/Akt/Nrf2 signaling, resulting in reduction of MRP1-mediated drug efflux and induction of Bax/Bcl-2-dependent apoptosis in an ADR-resistant K562/Adr leukemia cell line. - Highlights: • Chaetominine enhanced chemosensitivity of ADR against K562/Adr cells. • Chaetominine increased intracellular ADR levels via inhibiting MRP1. • Chaetominine induced apoptosis of K562/Adr cells through upregulation of ROS and modulation of Bax/Bcl-2. • Inhibition of MRP1 and Nrf2 by chaetominine treatment was correlative with blockade of PI3K/Akt signaling.

  1. Holotoxin A1 Induces Apoptosis by Activating Acid Sphingomyelinase and Neutral Sphingomyelinase in K562 and Human Primary Leukemia Cells

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    Seong-Hoon Yun

    2018-04-01

    Full Text Available Marine triterpene glycosides are attractive candidates for the development of anticancer agents. Holotoxin A1 is a triterpene glycoside found in the edible sea cucumber, Apostichopus (Stichopus japonicus. We previously showed that cladoloside C2, the 25(26-dihydro derivative of holotoxin A1, induced apoptosis in human leukemia cells by activating ceramide synthase 6. Thus, we hypothesized that holotoxin A1, which is structurally similar to cladoloside C2, might induce apoptosis in human leukemia cells through the same molecular mechanism. In this paper, we compared holotoxin A1 and cladoloside C2 for killing potency and mechanism of action. We found that holotoxin A1 induced apoptosis more potently than cladoloside C2. Moreover, holotoxin A1 induced apoptosis in K562 cells by activating caspase-8 and caspase-3, but not by activating caspase-9. During holotoxin A1-induced apoptosis, acid sphingomyelinase (SMase and neutral SMase were activated in both K562 cells and human primary leukemia cells. Specifically inhibiting acid SMase and neutral SMаse with chemical inhibitors or siRNAs significantly inhibited holotoxin A1–induced apoptosis. These results indicated that holotoxin A1 might induce apoptosis by activating acid SMase and neutral SMase. In conclusion, holotoxin A1 represents a potential anticancer agent for treating leukemia. Moreover, the aglycone structure of marine triterpene glycosides might affect the mechanism involved in inducing apoptosis.

  2. [Effect of Recombinant Adenovirus AdE-SH2-Caspase 8 on the Apoptosis of Imatinib-resistant K562/G01 Cell Line].

    Science.gov (United States)

    Wang, Lin; Fei, Chang; Huang, Zheng-Lan; Li, Hui; Liu, Zhang-Lin; Feng, Wen-Li

    2015-08-01

    To investigate the effect of SH2-Caspase 8 fusion protein expressed by recombinant adenovirus AdE-SH2-Caspase8-HA-GFP (SC) on the apoptosis of K562/G01 cell line, which is a BCR/ABL positive chronic myeloid leukemia cell line and resistant to imatinib. The K562/G01 cell line was infected with AdE-SH2-Caspase 8-HA-GFP adenovirus (SC), then the cells were divided into 3 groups: AdE-SH2m-Caspase 8-HA-GFP (SmC) group, AdE-GFP (CMV) group and PBS group as control. The infection efficiency was observed under fluorescent microscopy and by flow cytometry. The expression of fusion protein SH2-Caspase 8-HA was measured by Western blot. The morphology of the cells detected by Wright's staining. The apoptosis of the cells were detected by flow cytometry and DNA ladder. The expression of Caspase 3 and PARP were detected by Western blot. The infection efficiency of SC on K562/G01 cells was high which was confirmed by fluorescent microscopy and FCM. SH2-Caspase 8-HA fusion protein were expressed correctly in K562/G01 cells. After treatment with SC the apoptosis of K562/G01 cells could be observed by microscopy. The result of FCM showed that early apoptosis of K562/G01 cells increased significantly as compared with control groups (P SH2-Caspase 8 fusion protein can induces the apoptosis of K562/G01 cells.

  3. Apoptosis of leukemia K562 and Molt-4 cells induced by emamectin benzoate involving mitochondrial membrane potential loss and intracellular Ca2+ modulation.

    Science.gov (United States)

    Yun, Xinming; Rao, Wenbing; Xiao, Ciying; Huang, Qingchun

    2017-06-01

    Leukemia threatens millions of people's health and lives, and the pesticide-induced leukemia has been increasingly concerned because of the etiologic exposure. In this paper, cytotoxic effect of emamectin benzoate (EMB), an excellent natural-product insecticide, was evaluated through monitoring cell viability, cell apoptosis, mitochondrial membrane potential and intracellular Ca 2+ concentration ([Ca 2+ ] i ) in leukemia K562 and Molt-4 cells. Following the exposure to EMB, cell viability was decreased and positive apoptosis of K562 and Molt-4 cells was increased in a concentration- and time- dependent fashion. In the treatment of 10μM EMB, apoptotic cells accounted for 93.0% to K562 cells and 98.9% to Molt-4 cells based on the control, meanwhile, 63.47% of K562 cells and 81.15% of Molt-4 cells exhibited late apoptotic and necrotic features with damaged cytoplasmic membrane. 48h exposure to 10μM EMB increased significantly the great number of cells with mitochondrial membrane potential (MMP) loss, and the elevation of [Ca 2+ ] i level was peaked and persisted within 70s in K562 cells whilst 50s in Molt-4 cells. Moreover, a stronger cytotoxicity of EMB was further observed than that of imatinib. The results authenticate the efficacious effect of EMB as a potential anti-leukemia agent and an inconsistency with regard to insecticide-induced leukemia. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. A Subpopulation of the K562 Cells Are Killed by Curcumin Treatment after G2/M Arrest and Mitotic Catastrophe.

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    Macario Martinez-Castillo

    Full Text Available Curcumin is extensively investigated as a good chemo-preventive agent in the development of many cancers and particularly in leukemia, including treatment of chronic myelogenous leukemia and it has been proposed as an adjuvant for leukemia therapies. Human chronic myeloid leukemia cells (K562, were treated with 20 μM of curcumin, and we found that a subpopulation of these cells were arrested and accumulate in the G2/M phase of the cell cycle. Characterization of this cell subpopulation showed that the arrested cells presented nuclear morphology changes resembling those described for mitotic catastrophe. Mitotic cells displayed abnormal chromatin organization, collapse of the mitotic spindle and abnormal chromosome segregation. Then, these cells died in an apoptosis dependent manner and showed diminution in the protein levels of BCL-2 and XIAP. Moreover, our results shown that a transient activation of the nuclear factor κB (NFκB occurred early in these cells, but decreased after 6 h of the treatment, explaining in part the diminution of the anti-apoptotic proteins. Additionally, P73 was translocated to the cell nuclei, because the expression of the C/EBPα, a cognate repressor of the P73 gene, was decreased, suggesting that apoptosis is trigger by elevation of P73 protein levels acting in concert with the diminution of the two anti-apoptotic molecules. In summary, curcumin treatment might produce a P73-dependent apoptotic cell death in chronic myelogenous leukemia cells (K562, which was triggered by mitotic catastrophe, due to sustained BAX and survivin expression and impairment of the anti-apoptotic proteins BCL-2 and XIAP.

  5. MiR-27a Promotes Hemin-Induced Erythroid Differentiation of K562 Cells by Targeting CDC25B

    Directory of Open Access Journals (Sweden)

    Dongsheng Wang

    2018-03-01

    Full Text Available Background/Aims: MicroRNAs (miRNAs play a crucial role in erythropoiesis. MiR-23a∼27a∼24-2 clusters have been proven to take part in erythropoiesis via some proteins. CDC25B (cell division control Cdc2 phosphostase B is also the target of mir-27a; whether it regulates erythropoiesis and its mechanism are unknown. Methods: To evaluate the potential role of miR-27a during erythroid differentiation, we performed miR-27a gain- and loss-of-function experiments on hemin-induced K562 cells. We detected miR-27a expression after hemin stimulation at different time points. At the same time, the γ-globin gene also was measured via real-time PCR. According to the results of the chips, we screened the target protein of miR-27a through a dual-luciferase reporter assay and identified it via Western blot analyses. To evaluate the function of CDC25B, benzidine staining and flow cytometry were employed to detect the cell differentiation and cell cycle. Results: We found that miR-27a promotes hemin-induced erythroid differentiation of human K562 cells by targeting cell division cycle 25 B (CDC25B. Overexpression of miR-27a promotes the differentiation of hemin-induced K562 cells, as demonstrated by γ-globin overexpression. The inhibition of miR-27a expression suppresses erythroid differentiation, thus leading to a reduction in the γ-globin gene. CDC25B was identified as a new target of miR-27a during erythroid differentiation. Overexpression of miR-27a led to decreased CDC25B expression after hemin treatment, and CDC25B was up-regulated when miR-27a expression was inhibited. Moreover, the inhibition of CDC25B affected erythroid differentiation, as assessed by γ-globin expression. Conclusion: This study is the first report of the interaction between miR-27a and CDC25B, and it improves the understanding of miRNA functions during erythroid differentiation.

  6. Use of zinc-finger nucleases to knock out the WAS gene in K562 cells: a human cellular model for Wiskott-Aldrich syndrome

    Directory of Open Access Journals (Sweden)

    Miguel G. Toscano

    2013-03-01

    Mutations in the WAS gene cause Wiskott-Aldrich syndrome (WAS, which is characterized by eczema, immunodeficiency and microthrombocytopenia. Although the role of WASP in lymphocytes and myeloid cells is well characterized, its role on megakaryocyte (MK development is poorly understood. In order to develop a human cellular model that mimics the megakaryocytic-derived defects observed in WAS patients we used K562 cells, a well-known model for study of megakaryocytic development. We knocked out the WAS gene in K562 cells using a zinc-finger nuclease (ZFN pair targeting the WAS intron 1 and a homologous donor DNA that disrupted WASP expression. Knockout of WASP on K562 cells (K562WASKO cells resulted in several megakaryocytic-related defects such as morphological alterations, lower expression of CD41ɑ, lower increments in F-actin polymerization upon stimulation, reduced CD43 expression and increased phosphatidylserine exposure. All these defects have been previously described either in WAS-knockout mice or in WAS patients, validating K562WASKO as a cell model for WAS. However, K562WASPKO cells showed also increased basal F-actin and adhesion, increased expression of CD61 and reduced expression of TGFβ and Factor VIII, defects that have never been described before for WAS-deficient cells. Interestingly, these phenotypic alterations correlate with different roles for WASP in megakaryocytic differentiation. All phenotypic alterations observed in K562WASKO cells were alleviated upon expression of WAS following lentiviral transduction, confirming the role of WASP in these phenotypes. In summary, in this work we have validated a human cellular model, K562WASPKO, that mimics the megakaryocytic-related defects found in WAS-knockout mice and have found evidences for a role of WASP as regulator of megakaryocytic differentiation. We propose the use of K562WASPKO cells as a tool to study the molecular mechanisms involved in the megakaryocytic-related defects observed in WAS

  7. Influence of different metal ions on the ultrastructure, biochemical properties, and protein localization of the K562 cell nuclear matrix.

    Science.gov (United States)

    Neri, L M; Bortul, R; Zweyer, M; Tabellini, G; Borgatti, P; Marchisio, M; Bareggi, R; Capitani, S; Martelli, A M

    1999-06-01

    The higher order of chromatin organization is thought to be determined by the nuclear matrix, a mainly proteinaceous structure that would act as a nucleoskeleton. The matrix is obtained from isolated nuclei by a series of extraction steps involving the use of high salt and nonspecific nucleases, which remove chromatin and other loosely bound components. It is currently under debate whether these structures, isolated in vitro by unphysiological extraction buffers, correspond to a nucleoskeleton existing in vivo. In most cell types investigated, the nuclear matrix does not spontaneously resist these extractions steps; rather, it must be stabilized before the application of extracting agents. In this study nuclei, isolated from K562 human erythroleukemia cells, were stabilized by incubation with different metal ions (Ca2+, Cu2+, Zn2+, Cd2+), and the matrix was obtained by extraction with 2 M NaCl. By means of ultrastructural analysis of the resulting structures, we determined that, except for Ca2+, all the other metals induced a stabilization of the matrix, which retained the inner fibrogranular network and residual nucleoli. The biochemical composition, analyzed by two-dimensional gel electrophoresis separation, exhibited a distinct matrix polypeptide pattern, characteristic of each type of stabilizing ion employed. We also investigated to what extent metal ions could maintain in the final structures the original distribution of three inner matrix components, i.e. NuMA, topoisomerase IIalpha, and RNP. Confocal microscopy analysis showed that only NuMa, and, to a lesser extent, topoisomerase IIalpha, were unaffected by stabilization with divalent ions. On the contrary, the fluorescent RNP patterns detected in the resulting matrices were always disarranged, irrespective of the stabilization procedure. These results indicate that several metal ions are powerful stabilizing agents of the nuclear matrix prepared from K562 erythroleukemia cells and also strengthen the

  8. A nanocomplex of Cu(II) with theophylline drug; synthesis, characterization, and anticancer activity against K562 cell line

    Science.gov (United States)

    Sahlabadi, Maryam; Daryanavard, Marzieh; Hadadzadeh, Hassan; Amirghofran, Zahra

    2018-03-01

    A new mononuclear of copper (II), [Cu(theophylline)2(H2O)3]·2H2O, has been synthesized by reaction of theophylline (1,3-dimethyl-7H-purine-2,6-dione) with copper (II) nitrate in water. Further, its nanocomplex has been prepared through the three different methods including sonication, grinding, and a combination thereof, sonication-grinding. The prepared nanocomplex was characterized using different techniques including FT-IR, UV-Vis, X-ray diffraction (XRD) analysis, and field-emission scanning electron microscopy (FE-SEM). Moreover, the anticancer activity of the precursor complex, nanocomplex, free theophylline ligand, and the starting copper salt (Cu(NO3)2·3H2O) was investigated against the K562 cell line. The results show that the nanocomplex is an effective nano metal-based anticancer agent with IC50 = 11.7 μM.

  9. Involvement of CD147 on multidrug resistance through the regulation of P-glycoprotein expression in K562/ADR leukemic cell line

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    Aoranit Somno

    2016-01-01

    Full Text Available The relationship between P-gp and CD147 in the regulation of MDR in leukemic cells has not been reported. This study aimed to investigate the correlation between CD147 and P-gp in the regulation of drug resistance in the K562/ADR leukemic cell line. The results showed that drug-resistant K562/ADR cells expressed significantly higher P-gp and CD147 levels than drug-free K562/ADR cells. To determine the regulatory effect of CD147 on P-gp expression, anti-CD147 antibody MEM-M6/6 significantly decreased P-gp and CD147 mRNA and protein levels. This is the first report to show that CD147 mediates MDR in leukemia through the regulation of P-gp expression.

  10. Bcr-Abl-independent mechanism of resistance to imatinib in K562 cells: Induction of cyclooxygenase-2 (COX-2) by histone deacetylases (HDACs).

    Science.gov (United States)

    Kalle, Arunasree M; Sachchidanand, Sachchidanand; Pallu, Reddanna

    2010-09-01

    Our previous studies have shown that overexpression of MDR1 and cyclooygenase-2 (COX-2) resulted in resistance development to imatinib in chronic myelogenous leukemia (CML) K562 (IR-K562) cells. In the present study, the regulatory mechanism of MDR1 induction by COX-2 was investigated. A gradual overexpression of MDR1 and COX-2 during the process of development was observed. Furthermore, down regulation of MDR1 upon COX-2 knockdown by siRNA showed a decrease in the PKC levels and activation of PKC by addition of PGE(2) to K562 cells, suggesting a role for PKC in the COX-2 mediated induction of MDR1. The present study demonstrates COX-2 induction by HDACs and MDR1 induction by COX-2 via PGE(2)-cAMP-PKC-mediated pathway. Copyright 2010 Elsevier Ltd. All rights reserved.

  11. Induction of Mitochondrial Dependent Apoptosis in Human Leukemia K562 Cells by Meconopsis integrifolia: A Species from Traditional Tibetan Medicine

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    Jianping Fan

    2015-06-01

    Full Text Available Objectives: Meconopsis integrifolia (M. integrifolia is one of the most popular members in Traditional Tibetan Medicine. This study aimed to investigate the anticancer effect of M. integrifolia and to detect the underlying mechanisms of these effects. Methods: 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyl tetrazolium bromide (MTT assay and trypan blue assay were used to evaluate the cytotoxicity of M. integrifolia. Changes in cell nuclear morphology and reactive oxygen species (ROS level were observed by fluorescent microscopy. Apoptosis ratio, DNA damage and mitochondrial membrane potential (MMP loss were analyzed by flow cytometry. Western blotting assay was adopted to detect the proteins related to apoptosis. Immunofluorescence was used to observe the release of cytochrome C. Results: The obtained data revealed that M. integrifolia could significantly inhibit K562 cell viability, mainly by targeting apoptosis induction and cell cycle arrest in G2/M phase. Collapse in cell morphology, chromatin condensation, DNA damage and ROS accumulation were observed. Further mechanism detection revealed that mitochondrion might be a key factor in M. integrifolia-induced apoptosis. Conclusions: M. integrifolia could induce mitochondria mediated apoptosis and cell cycle arrest in G2/M phase with little damage to normal cells, suggesting that M. integrifolia might be a potential and efficient anticancer agent that deserves further investigation.

  12. Effect of taurine on expressions of MMP-2 in K562 leukemia cell line exposed to γ-rays

    International Nuclear Information System (INIS)

    Fan Yan; Wu Shiliang; Xu Lan; Chou Hao; Zhou Yinghui

    2003-01-01

    Objective: To study the effect of γ-irradiation on expressions of MMP-2 in leukaemia cells and the suppressive effect of taurine(Tau) on irradiated tumour cells in terms of cellular level. Methods: The cells in the control group and Tau (50 mg/L, 100 mg/L, 200 mg/L) groups were irradiated with 15 Gy γ-rays. The expressions of MMP-2 were examined through Western-blotting after handled with gel-loading buffer within 12 h. Results: The expressions of MMP-2 were enhanced evidently in the positive control group, while they were less in the negative control group. In the Tau(50 mg/L, 100 mg/L, 200 mg/L) groups, the expressions of MMP-2 were diminished in turns, and they were almost identical between the negative control group and the Tau 200 mg/L group. Conclusion: Irradiation with γ-rays at a dose of 15 Gy can significantly stimulate the expressions of MMP-2 in K562 cells; Tau can inhibit the expressions of MMP-2 and its effect depends on to its dosage; Tau can inhabit the invasiveness and migration of irradiated tumour cells, so it has the biologic protective and therapeutic effects

  13. Heme-binding plasma membrane proteins of K562 erythroleukemia cells: Adsorption to heme-microbeads, isolation with affinity chromatography

    International Nuclear Information System (INIS)

    Majuri, R.

    1989-01-01

    Heme-microbeads attached themselves to the surface of viable K562 cells in a manner inhibitable by free hemin, indicating heme-recptor interaction. The microbeads were at first evenly distributed, but after prolonged incubation at 37 deg. C they formed a cap on one pole of the cells indicating clustering of the membrane heme receptors. Membrane proteins were labeled by culturing the cells in the presence of 35 S-methionine and were then solubilized with Triton X-114. The hydrophobic proteins contained about 20% of the total bound label. The solubilized membrane proteins were subsequently adsorbed to a heme-Sepharose affinity gel. According to SDS-electrophorsis and subsequent autoradiography, the immobilized heme captures two proteins or a protein with two polypeptides of 20 000 and 32 000 daltons. The larger of these was only wekly labeled with 35 S. The same two bands were observed if the cell surface proteins were labeled with 125 I by the lactoperoxidase method and the subsequently solubilized membrane proteins were isolated with heme-Sepharose. (author)

  14. Complete genome of Phenylobacterium zucineum – a novel facultative intracellular bacterium isolated from human erythroleukemia cell line K562

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    Sun Jie

    2008-08-01

    Full Text Available Abstract Background Phenylobacterium zucineum is a recently identified facultative intracellular species isolated from the human leukemia cell line K562. Unlike the known intracellular pathogens, P. zucineum maintains a stable association with its host cell without affecting the growth and morphology of the latter. Results Here, we report the whole genome sequence of the type strain HLK1T. The genome consists of a circular chromosome (3,996,255 bp and a circular plasmid (382,976 bp. It encodes 3,861 putative proteins, 42 tRNAs, and a 16S-23S-5S rRNA operon. Comparative genomic analysis revealed that it is phylogenetically closest to Caulobacter crescentus, a model species for cell cycle research. Notably, P. zucineum has a gene that is strikingly similar, both structurally and functionally, to the cell cycle master regulator CtrA of C. crescentus, and most of the genes directly regulated by CtrA in the latter have orthologs in the former. Conclusion This work presents the first complete bacterial genome in the genus Phenylobacterium. Comparative genomic analysis indicated that the CtrA regulon is well conserved between C. crescentus and P. zucineum.

  15. Involvement of p38 MAPK- and JNK-modulated expression of Bcl-2 and Bax in Naja nigricollis CMS-9-induced apoptosis of human leukemia K562 cells.

    Science.gov (United States)

    Chen, Ying-Jung; Liu, Wen-Hsin; Kao, Pei-Hsiu; Wang, Jeh-Jeng; Chang, Long-Sen

    2010-06-15

    CMS-9, a phospholipase A(2) (PLA(2)) isolated from Naja nigricollis venom, induced apoptosis of human leukemia K562 cells, characterized by mitochondrial depolarization, modulation of Bcl-2 family members, cytochrome c release and activation of caspases 9 and 3. Moreover, an increase in intracellular Ca2+ concentration and the production of reactive oxygen species (ROS) was noted. Pretreatment with BAPTA-AM (Ca2+ chelator) and N-acetylcysteine (NAC, ROS scavenger) proved that Ca2+ was an upstream event in inducing ROS generation. Upon exposure to CMS-9, activation of p38 MAPK and JNK was observed in K562 cells. BAPTA-AM or NAC abrogated CMS-9-elicited p38 MAPK and JNK activation, and rescued viability of CMS-9-treated K562 cells. SB202190 (p38 MAPK inhibitor) and SP600125 (JNK inhibitor) suppressed CMS-9-induced dissipation of mitochondrial membrane potential, Bcl-2 down-regulation, Bax up-regulation and increased mitochondrial translocation of Bax. Inactivation of PLA(2) activity reduced drastically the cytotoxicity of CMS-9, and a combination of lysophosphatidylcholine and stearic acid mimicked the cytotoxic effects of CMS-9. Taken together, our data suggest that CMS-9-induced apoptosis of K562 cells is catalytic activity-dependent and is mediated through mitochondria-mediated death pathway triggered by Ca2+/ROS-evoked p38 MAPK and JNK activation. 2010 Elsevier Ltd. All rights reserved.

  16. Evaluation of Synergetic Anticancer Activity of Berberine and Curcumin on Different Models of A549, Hep-G2, MCF-7, Jurkat, and K562 Cell Lines

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    Acharya Balakrishna

    2015-01-01

    Full Text Available Ayurvedic system of medicine is using Berberis aristata and Curcuma longa herbs to treat different diseases including cancer. The study was performed to evaluate the synergetic anticancer activity of Berberine and Curcumin by estimating the inhibition of the cell proliferation by cytotoxicity assay using MTT method on specified human cell lines (A549, Hep-G2, MCF-7, Jurkat, and K562. All the cells were harvested from the culture and seeded in the 96-well assay plates at seeding density of 2.0 × 104 cells/well and were incubated for 24 hours. Test items Berberine with Curcumin (1 : 1, Curcumin 95% pure, and Berberine 95% pure were exposed at the concentrations of 1.25, 0.001, and 0.5 mg/mL, respectively, and incubated for a period of 48 hours followed by dispensing MTT solution (5 mg/mL. The cells were incubated at 37 ± 1°C for 4 hours followed by addition of DMSO for dissolving the formazan crystals and absorbance was read at 570 nm. Separate wells were prepared for positive control, controls (only medium with cells, and blank (only medium. The results had proven the synergetic anticancer activity of Berberine with Curcumin inducing cell death greater percentage of >77% when compared to pure curcumin with <54% and pure Berberine with <45% on average on all cell line models.

  17. SENYAWA BIOAKTIF RIMPANG JAHE (Zingiber officinale Roscue MENINGKATKAN RESPON SITOLITIK SEL NK TERHADAP SEL KANKER DARAH K-562 IN VITRO [Ginger Root Bioactive Compounds Increased Cytolitic Response of Natural Killer (NK Cells Against Leucemic Cell Line K-562 In Vitro

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    Fransiska Rungkat Zakaria 2

    2006-08-01

    Full Text Available Natural killer (NK cell, a kind of lymphocyte cells, plays an important role in attacking infectious, immature, and cancer cell. Its function could be modulated by food bioactive compounds. This experiment was conducted to investigate the effects of ginger root bioactive compounds such as oleoresin, gingerol, and shogaol on cytolitic response of NK cell in vitro. Lymphocyte cells were isolated by centrifugation on ficoll-hypaque density (1,77 ?0,001 g/ml method. Leukemic cells line K-562 as target cells(TC labelled by [3H]-timidin, together with lymphocyte as effector cell (EC were cultured in two ratio levels of EC : TC equal to 1:50 and 1:100, and two culture conditions, for 4 hours, respectively. Paraquate dichloride (1,1-dimethyl-4,4-bipyridilium dichloride 3 mM was used to induce stress oxidative circumstance. Cytolytic capacity of NK cells was determined by percentage of TC lysed by NK cells, in normal and oxidative stress conditions. Statistical analysis showed that the effects of ginger bioactive compounds on cytolytic response of NK cell depended on the culture conditions, as shown by cultures in the presence of oleoresin, and gingerol, but not shogaol. In the lymphocyte culture without stress oxidative, oleoresin, gingerol and shogaol compounds increased significantly cytolytic response of NK cells cultured at a ratio of TC : EC equal to 1:50, with the highest increament of 65 % at oleoresin concentration of 50 ?g/ml. However, in culture at a ratio of TC : EC equals to 1:100, only oleoresin at a concentration of 50 ?g/ml increased significantly cytolytic response of NK cells with the highest increament of 8 %. Shogaol did not affect significantly NK cells cytolytic response. Under stress oxidative conditions, shogaol increased significantly cytolytic response of NK cells cultured at a ratio of TC:EC equal to 1:50, but the highest increament of 56 % , was by oleoresin at concentration of 50 ?g/ml. Meanwhile, oleoresin and gingerol did

  18. Heat stress causes spatially-distinct membrane re-modelling in K562 leukemia cells.

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    Gábor Balogh

    Full Text Available Cellular membranes respond rapidly to various environmental perturbations. Previously we showed that modulations in membrane fluidity achieved by heat stress (HS resulted in pronounced membrane organization alterations which could be intimately linked to the expression and cellular distribution of heat shock proteins. Here we examine heat-induced membrane changes using several visualisation methods. With Laurdan two-photon microscopy we demonstrate that, in contrast to the enhanced formation of ordered domains in surface membranes, the molecular disorder is significantly elevated within the internal membranes of cells preexposed to mild HS. These results were compared with those obtained by anisotropy, fluorescence lifetime and electron paramagnetic resonance measurements. All probes detected membrane changes upon HS. However, the structurally different probes revealed substantially distinct alterations in membrane heterogeneity. These data call attention to the careful interpretation of results obtained with only a single label. Subtle changes in membrane microstructure in the decision-making of thermal cell killing could have potential application in cancer therapy.

  19. Co-ordinate expression of activin A and its type I receptor mRNAs during phorbol ester-induced differentiation of human K562 erythroleukemia cells.

    Science.gov (United States)

    Hildén, K; Tuuri, T; Erämaa, M; Ritvos, O

    1999-07-20

    Activins were originally isolated based on their ability to stimulate follicle-stimulating hormone secretion but later they have been shown to regulate a number of different cellular functions such as nerve cell survival, mesoderm induction during early embryogenesis as well as hematopoiesis. We studied the regulation of activin A, a homodimer of betaA-subunits, mRNA and protein in K562 erythroleukemia cells, which are known to be induced toward the erythroid lineage in response to activin or TGF-beta or toward the megakaryocytic lineage by the phorbol ester protein kinase C activator 12-O-tetradecanoylphorbol-13-acetate (TPA). Here we show by Northern blot analysis as well as by Western and ligand blotting that TPA strongly promotes activin betaA-subunit mRNA and activin A protein expression in K562 cells in time- and concentration dependent manner. In contrast, neither activin A nor TGF-beta induced betaA-subunit mRNA expression during erythroid differentiation in K562 cells. Interestingly, whereas activin type II receptors are not regulated during K562 cell differentiation (Hilden et al. (1994) Blood 83, 2163-2170), we now show that the activin type I and IB receptor mRNAs are clearly induced by TPA but not by activin or TGF-beta. We also show that the inducing effect of TPA on expression of activin betaA-subunit mRNA is potentiated by the protein kinase A activator 8-bromo-cAMP. We conclude that activin A and its type I receptors appear to be co-ordinately up-regulated during megakaryocytic differentiation of K562 cells.

  20. Induced apoptosis by mild hyperthermia occurs via telomerase inhibition on the three human myeloid leukemia cell lines: TF-1, K562, and HL-60.

    Science.gov (United States)

    Deezagi, Abdolkhaleg; Manteghi, Sanaz; Khosravani, Pardis; Vaseli-Hagh, Neda; Soheili, Zahra-Soheila

    2009-09-01

    The purpose of this research was to understand the effect of hyperthermia on the telomerase activity in human leukemic cell lines (HL-60, K562, and TF-1). The cells were treated by hyperthermia at the range of 41-44 degrees C for 120 min and incubated for 96 h. Then telomerase activity, cell proliferation, and apoptosis were assessed. The results indicated that hyperthermia significantly induced apoptosis on the cells. The cells exhibited pre-apoptotic pattern at 41 and 42 degrees C at 60-120 min and apoptotic pattern at 43 and 44 degrees C over 30 min after hyperthermia. Telomerase activity (that was assayed immediately after hyperthermia) was stable at 41-42 degrees C for 60 min but decreased to 35-40% at 120 min. However, at severe hyperthermia (43-44 degrees C) telomerase activity was decreased in a time- and dose-dependent manner. Following hyperthermia (41-44 degrees C up to 120 min), the cells were incubated for 96 h. In these conditions, the telomerase activity was decreased by about 60-80% in comparison with that untreated control cells.

  1. Oxidative stress by ascorbate/menadione association kills K562 human chronic myelogenous leukaemia cells and inhibits its tumour growth in nude mice.

    Science.gov (United States)

    Verrax, Julien; Stockis, Julie; Tison, Aurélie; Taper, Henryk S; Calderon, Pedro Buc

    2006-09-14

    The effect of oxidative stress induced by the ascorbate/menadione-redox association was examined in K562 cells, a human erythromyeloid leukaemia cell line. Our results show that ascorbate enhances menadione redox cycling, leading to the formation of intracellular reactive oxygen species (as shown by dihydrorhodamine 123 oxidation). The incubation of cells in the presence of both ascorbate/menadione and aminotriazole, a catalase inhibitor, resulted in a strong decrease of cell survival, reinforcing the role of H(2)O(2) as the main oxidizing agent killing K562 cells. This cell death was not caspase-3-dependent. Indeed, neither procaspase-3 and PARP were processed and only a weak cytochrome c release was observed. Moreover, we observed only 23% of cells with depolarized mitochondria. In ascorbate/menadione-treated cells, DNA fragmentation was observed without any sign of chromatin condensation (DAPI and TUNEL tests). The cell demise by ascorbate/menadione is consistent with a necrosis-like cell death confirmed by both cytometric profile of annexin-V/propidium iodide labeled cells and by light microscopy examination. Finally, we showed that a single i.p. administration of the association of ascorbate and menadione is able to inhibit the growth of K562 cells by about 60% (in both tumour size and volume) in an immune-deficient mice model. Taken together, these results reinforced our previous claims about a potential application of the ascorbate/menadione association in cancer therapy.

  2. Analysis of the Effects of δ-Tocopherol on RAW264.7 and K562 Cells Based on 1H NMR Metabonomics.

    Science.gov (United States)

    Lu, Yang; Li, Hui; Geng, Yue

    2018-01-31

    δ-Tocopherol (δ-TOH) is a form of vitamin E with higher bioactivity. In this study, we studied the bioactivity of δ-TOH using the IC 50 of δ-TOH on RAW264.7 (80 μM) and K562 (110 μM) cells. We compared the differential metabolites from the cell lines with and without δ-TOH treatment by 1 H NMR metabonomics analysis. It was found that δ-TOH affected the protein biosynthesis, betaine metabolism, and urea cycle in various ways in both cell lines. Metabolic levels of the cell lines were changed after treatment with δ-TOH as differential metabolites were produced. The betaine level in RAW264.7 cells was reduced significantly, while the l-lactic acid level in K562 cells was significantly enhanced. The metabolic changes might contribute to the switch of the respiration pattern from aerobic respiration to anaerobic respiration in K562 cells. These results are helpful in further understanding the subtoxicity of δ-TOH.

  3. Knockdown of HOXA10 reverses the multidrug resistance of human chronic mylogenous leukemia K562/ADM cells by downregulating P-gp and MRP-1.

    Science.gov (United States)

    Yi, Ying-Jie; Jia, Xiu-Hong; Wang, Jian-Yong; Li, You-Jie; Wang, Hong; Xie, Shu-Yang

    2016-05-01

    Multidrug resistance (MDR) of leukemia cells is a major obstacle in chemotherapeutic treatment. The high expression and constitutive activation of P-glycoprotein (P-gp) and multidrug resistance protein-1 (MRP-1) have been reported to play a vital role in enhancing cell resistance to anticancer drugs in many tumors. The present study aimed to investigate the reversal of MDR by silencing homeobox A10 (HOXA10) in adriamycin (ADR)-resistant human chronic myelogenous leukemia (CML) K562/ADM cells by modulating the expression of P-gp and MRP-1. K562/ADM cells were stably transfected with HOXA10-targeted short hairpin RNA (shRNA). The results of reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blot analysis showed that the mRNA and protein expression of HOXA10 was markedly suppressed following transfection with a shRNA-containing vector. The sensitivity of the K562/ADM cells to ADR was enhanced by the silencing of HOXA10, due to the increased intracellular accumulation of ADR. The accumulation of ADR induced by the silencing of HOXA10 may be due to the downregulation of P-gp and MRP-1. Western blot analysis revealed that downregulating HOXA10 inhibited the protein expression of P-gp and MRP-1. Taken together, these results suggest that knockdown of HOXA10 combats resistance and that HOXA10 is a potential target for resistant human CML.

  4. PaDef defensin from avocado (Persea americana var. drymifolia) is cytotoxic to K562 chronic myeloid leukemia cells through extrinsic apoptosis.

    Science.gov (United States)

    Flores-Alvarez, Luis José; Guzmán-Rodríguez, Jaquelina Julia; López-Gómez, Rodolfo; Salgado-Garciglia, Rafael; Ochoa-Zarzosa, Alejandra; López-Meza, Joel E

    2018-06-01

    Plant defensins, a group of antimicrobial peptides, show selective cytotoxicity toward cancer cells. However, their mechanisms of action remain poorly understood. Here, we evaluated the cytotoxicity of PaDef defensin from avocado (Persea americana var. drymifolia) on K562 chronic myeloid leukemia cells and analyzed the pathway involved in the induction of cell death. The defensin PaDef was not cytotoxic against human PBMCs; however, it was cytotoxic for K562 cell line (IC 50  = 97.3 μg/ml) activating apoptosis at 12 h. PaDef did not affect the mitochondrial membrane potential (ΔΨm), neither the transmembranal potential or the release of intracellular calcium. Also, PaDef induced gene expression of caspase 8 (∼2 fold), TNF-α (∼4 fold) and TNFR1 (∼10 fold). In addition, the activation of caspase 8 was detected at 24 h, whereas caspase 9 activity was not modified, suggesting that the extrinsic apoptosis pathway could be activated. In conclusion, PaDef induces apoptosis on K562 cells, which is related to the activation of caspase 8 and involves the participation of TNF-α, which is a novel property for a plant defensin. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. Effects of light irradiation upon photodynamic therapy based on 5-aminolevulinic acid–gold nanoparticle conjugates in K562 cells via singlet oxygen generation

    Directory of Open Access Journals (Sweden)

    Xu H

    2012-09-01

    Full Text Available Hao Xu, Chen Liu, Jiansheng Mei, Cuiping Yao, Sijia Wang, Jing Wang, Zheng Li, Zhenxi ZhangKey Laboratory of Biomedical Information Engineering of Education Ministry, Institute of Biomedical Analytical Technology and Instrumentation, School of Life Science and Technology, Xi’an Jiaotong University, Xi’an, Shannxi, People’s Republic of ChinaPurpose: As a precursor of the potent photosensitizer protoporphyrin IX (PpIX, 5-aminolevulinic acid (5-ALA, was conjugated onto cationic gold nanoparticles (GNPs to improve the efficacy of photodynamic therapy (PDT.Methods: Cationic GNPs reduced by branched polyethyleneimine and 5-ALA were conjugated onto the cationic GNPs by creating an electrostatic interaction at physiological pH. The efficacy of ALA-GNP conjugates in PDT was investigated under irradiation with a mercury lamp (central wavelength of 395 nm and three types of light-emitting diode arrays (central wavelengths of 399, 502, and 621 nm, respectively. The impacts of GNPs on PDT were then analyzed by measuring the intracellular PpIX levels in K562 cells and the singlet oxygen yield of PpIX under irradiation.Results: The 2 mM ALA-GNP conjugates showed greater cytotoxicity against K562 cells than ALA alone. Light-emitting diode (505 nm irradiation of the conjugates caused a level of K562 cell destruction similar to that with irradiation by a mercury lamp, although it had no adverse effects on drug-free control cells. These results may be attributed to the singlet oxygen yield of PpIX, which can be enhanced by GNPs.Conclusion: Under irradiation with a suitable light source, ALA-GNP conjugates can effectively destroy K562 cells. The technique offers a new strategy of PDT.Keywords: nonradiative energy transfer, photodamage, protoporphyrin IX, selective destruction, singlet oxygen sensor green reagent, surface plasmon resonance

  6. Stat5 Exerts Distinct, Vital Functions in the Cytoplasm and Nucleus of Bcr-Abl+ K562 and Jak2(V617F)+ HEL Leukemia Cells

    International Nuclear Information System (INIS)

    Weber, Axel; Borghouts, Corina; Brendel, Christian; Moriggl, Richard; Delis, Natalia; Brill, Boris; Vafaizadeh, Vida; Groner, Bernd

    2015-01-01

    Signal transducers and activators of transcription (Stats) play central roles in the conversion of extracellular signals, e.g., cytokines, hormones and growth factors, into tissue and cell type specific gene expression patterns. In normal cells, their signaling potential is strictly limited in extent and duration. The persistent activation of Stat3 or Stat5 is found in many human tumor cells and contributes to their growth and survival. Stat5 activation plays a pivotal role in nearly all hematological malignancies and occurs downstream of oncogenic kinases, e.g., Bcr-Abl in chronic myeloid leukemias (CML) and Jak2(V617F) in other myeloproliferative diseases (MPD). We defined the mechanisms through which Stat5 affects growth and survival of K562 cells, representative of Bcr-Abl positive CML, and HEL cells, representative for Jak2(V617F) positive acute erythroid leukemia. In our experiments we suppressed the protein expression levels of Stat5a and Stat5b through shRNA mediated downregulation and demonstrated the dependence of cell survival on the presence of Stat5. Alternatively, we interfered with the functional capacities of the Stat5 protein through the interaction with a Stat5 specific peptide ligand. This ligand is a Stat5 specific peptide aptamer construct which comprises a 12mer peptide integrated into a modified thioredoxin scaffold, S5-DBD-PA. The peptide sequence specifically recognizes the DNA binding domain (DBD) of Stat5. Complex formation of S5-DBD-PA with Stat5 causes a strong reduction of P-Stat5 in the nuclear fraction of Bcr-Abl-transformed K562 cells and a suppression of Stat5 target genes. Distinct Stat5 mediated survival mechanisms were detected in K562 and Jak2(V617F)-transformed HEL cells. Stat5 is activated in the nuclear and cytosolic compartments of K562 cells and the S5-DBD-PA inhibitor most likely affects the viability of Bcr-Abl + K562 cells through the inhibition of canonical Stat5 induced target gene transcription. In HEL cells, Stat5

  7. Celecoxib sensitizes imatinib-resistant K562 cells to imatinib by inhibiting MRP1-5, ABCA2 and ABCG2 transporters via Wnt and Ras signaling pathways.

    Science.gov (United States)

    Dharmapuri, Gangappa; Doneti, Ravinder; Philip, Gundala Harold; Kalle, Arunasree M

    2015-07-01

    Imatinib mesylate, a tyrosine kinase inhibitor, is very effective in the treatment of chronic myeloid leukemia (CML). However, development of resistance to imatinib therapy is also a very common mechanism observed with long-term administration of the drug. Our previous studies have highlighted the role of cyclooxygenase-2 (COX-2) in regulating the expression of multidrug resistant protein-1 (MDR1), P-gp, in imatinib-resistant K562 cells (IR-K562) via PGE2-cAMP-PKC-NF-κB pathway and inhibition of COX-2 by celecoxib, a COX-2 specific inhibitor, inhibits this pathway and reverses the drug resistance. Studies have identified that not only MDR1 but other ATP-binding cassette transport proteins (ABC transporters) are involved in the development of imatinib resistance. Here, we tried to study the role of COX-2 in the regulation of other ABC transporters such as MRP1, MRP2, MRP3, ABCA2 and ABCG2 that have been already implicated in imatinib resistance development. The results of the study clearly indicated that overexpression of COX-2 lead to upregulation of MRP family proteins in IR-K562 cells and celecoxib down-regulated the ABC transporters through Wnt and MEK signaling pathways. The study signifies that celecoxib in combination with the imatinib can be a good alternate treatment strategy for the reversal of imatinib resistance. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Natural and semi-synthetic clerodanes of Croton cajucara and their cytotoxic effects against ehrlich carcinoma and human K562 leukemia cells

    Energy Technology Data Exchange (ETDEWEB)

    Maciel, Maria Aparecida M. [Universidade Federal do Rio Grande do Norte, Natal, RN (Brazil). Dept. de Quimica; Martins, Jenilce R.; Pinto, Angelo C.; Kaiser, Carlos R. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Inst. de Quimica; Esteves-Souza, Andressa; Echevarria, Aurea [Universidade Federal Rural do Rio de Janeiro, Seropedica, RJ (Brazil). Dept. de Quimica]. E-mail: echevarr@ufrrj.br

    2007-03-15

    The clerodane-type diterpene, trans-dehydrocrotonin (1) the major component of Croton cajucara has shown striking correlation with its therapeutic use in traditional folk medicine. Phytochemical investigations led to the isolation of the metabolites 1, cajucarinolide (6), isocajucarinolide (7), trans-crotonin (2), trans-cajucarin B (3), cis-cajucarin B (4), trans-cajucarin A (5), N-methyltyrosine, vanillic acid and 4-hydroxy-benzoic acid. 6 and 7 were synthesized in good yield by regiospecific oxidation of 1 using singlet-oxygen. All clerodanes were studied for their cytotoxic effects against human K562 leukemia and Ehrlich carcinoma cells. Ehrlich carcinoma assays with IC{sub 50} = 166 {mu}M (1), 164 {mu}M (2), 65 {mu}M (6) and 10 {mu}M (7) related to cell growth inhibitory effects were dose dependent. Furthermore, moderate cytotoxic activity against K562 leukemia cells was observed with IC{sub 50} = 38 {mu}M (3), 33 {mu}M (5), 36 {mu}M (6) and 43 {mu}M (7). The semi-synthetic 2, 6 and 7 showed similar results when compared to the corresponding natural clerodanes. (author)

  9. Natural and semi-synthetic clerodanes of Croton cajucara and their cytotoxic effects against ehrlich carcinoma and human K562 leukemia cells

    International Nuclear Information System (INIS)

    Maciel, Maria Aparecida M.; Martins, Jenilce R.; Pinto, Angelo C.; Kaiser, Carlos R.; Esteves-Souza, Andressa; Echevarria, Aurea

    2007-01-01

    The clerodane-type diterpene, trans-dehydrocrotonin (1) the major component of Croton cajucara has shown striking correlation with its therapeutic use in traditional folk medicine. Phytochemical investigations led to the isolation of the metabolites 1, cajucarinolide (6), isocajucarinolide (7), trans-crotonin (2), trans-cajucarin B (3), cis-cajucarin B (4), trans-cajucarin A (5), N-methyltyrosine, vanillic acid and 4-hydroxy-benzoic acid. 6 and 7 were synthesized in good yield by regiospecific oxidation of 1 using singlet-oxygen. All clerodanes were studied for their cytotoxic effects against human K562 leukemia and Ehrlich carcinoma cells. Ehrlich carcinoma assays with IC 50 = 166 μM (1), 164 μM (2), 65 μM (6) and 10 μM (7) related to cell growth inhibitory effects were dose dependent. Furthermore, moderate cytotoxic activity against K562 leukemia cells was observed with IC 50 = 38 μM (3), 33 μM (5), 36 μM (6) and 43 μM (7). The semi-synthetic 2, 6 and 7 showed similar results when compared to the corresponding natural clerodanes. (author)

  10. Recombinant adeno-associated virus mediates a high level of gene transfer but less efficient integration in the K562 human hematopoietic cell line.

    Science.gov (United States)

    Malik, P; McQuiston, S A; Yu, X J; Pepper, K A; Krall, W J; Podsakoff, G M; Kurtzman, G J; Kohn, D B

    1997-03-01

    We tested the ability of a recombinant adeno-associated virus (rAAV) vector to express and integrate exogenous DNA into human hematopoietic cells in the absence of selection. We developed an rAAV vector, AAV-tNGFR, carrying a truncated rat nerve growth factor receptor (tNGFR) cDNA as a cell surface reporter under the control of the Moloney murine leukemia virus (MoMuLV) long terminal repeat. An analogous MoMuLV-based retroviral vector (L-tNGFR) was used in parallel, and gene transfer and expression in human hematopoietic cells were assessed by flow cytometry and DNA analyses. Following gene transfer into K562 cells with AAV-tNGFR at a multiplicity of infection (MOI) of 13 infectious units (IU), 26 to 38% of cells expressed tNGFR on the surface early after transduction, but the proportion of tNGFR expressing cells steadily declined to 3.0 to 3.5% over 1 month of culture. At an MOI of 130 IU, nearly all cells expressed tNGFR immediately posttransduction, but the proportion of cells expressing tNGFR declined to 62% over 2 months of culture. The decline in the proportion of AAV-tNGFR-expressing cells was associated with ongoing losses of vector genomes. In contrast, K562 cells transduced with the retroviral vector L-tNGFR expressed tNGFR in a constant fraction. Integration analyses on clones showed that integration occurred at different sites. Integration frequencies were estimated at about 49% at an MOI of 130 and 2% at an MOI of 1.3. Transduction of primary human CD34+ progenitor cells by AAV-tNGFR was less efficient than with K562 cells and showed a declining percentage of cells expressing tNGFR over 2 weeks of culture. Thus, purified rAAV caused very high gene transfer and expression in human hematopoietic cells early after transduction, which steadily declined during cell passage in the absence of selection. Although the efficiency of integration was low, overall integration was markedly improved at a high MOI. While prolonged episomal persistence may be adequate

  11. Expression of bovine non-classical major histocompatibility complex class I proteins in mouse P815 and human K562 cells.

    Science.gov (United States)

    Parasar, Parveen; Wilhelm, Amanda; Rutigliano, Heloisa M; Thomas, Aaron J; Teng, Lihong; Shi, Bi; Davis, William C; Suarez, Carlos E; New, Daniel D; White, Kenneth L; Davies, Christopher J

    2016-08-01

    Major histocompatibility complex class I (MHC-I) proteins can be expressed as cell surface or secreted proteins. To investigate whether bovine non-classical MHC-I proteins are expressed as cell surface or secreted proteins, and to assess the reactivity pattern of monoclonal antibodies with non-classical MHC-I isoforms, we expressed the MHC proteins in murine P815 and human K562 (MHC-I deficient) cells. Following antibiotic selection, stably transfected cell lines were stained with H1A or W6/32 antibodies to detect expression of the MHC-I proteins by flow cytometry. Two non-classical proteins (BoLA-NC1*00501 and BoLA-NC3*00101) were expressed on the cell surface in both cell lines. Surprisingly, the BoLA-NC4*00201 protein was expressed on the cell membrane of human K562 but not mouse P815 cells. Two non-classical proteins (BoLA-NC1*00401, which lacks a transmembrane domain, and BoLA-NC2*00102) did not exhibit cell surface expression. Nevertheless, Western blot analyses demonstrated expression of the MHC-I heavy chain in all transfected cell lines. Ammonium-sulfate precipitation of proteins from culture supernatants showed that BoLA-NC1*00401 was secreted and that all surface expressed proteins where shed from the cell membrane by the transfected cells. Interestingly, the surface expressed MHC-I proteins were present in culture supernatants at a much higher concentration than BoLA-NC1*00401. This comprehensive study shows that bovine non-classical MHC-I proteins BoLA-NC1*00501, BoLA-NC3*00101, and BoLA-NC4*00201 are expressed as surface isoforms with the latter reaching the cell membrane only in K562 cells. Furthermore, it demonstrated that BoLA-NC1*00401 is a secreted isoform and that significant quantities of membrane associated MHC-I proteins can be shed from the cell membrane. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  12. Dual Functions of the C5a Receptor as a Connector for the K562 Erythroblast-Like Cell-THP-1 Macrophage-Like Cell Island and as a Sensor for the Differentiation of the K562 Erythroblast-Like Cell during Haemin-Induced Erythropoiesis

    Directory of Open Access Journals (Sweden)

    Hiroshi Nishiura

    2012-01-01

    Full Text Available The transcriptional nuclear factor binding to the Y box of human leukocyte antigen genes (NF-Y for the C5a receptor (C5aR gene is active in erythroblasts. However, the roles of the C5aR in erythropoiesis are unclear. We have previously demonstrated that apoptotic cell-derived ribosomal protein S19 (RP S19 oligomers exhibit extraribosomal functions in promoting monocyte chemotaxis and proapoptosis via the C5aR without receptor internalisation. In contrast to the extraribosomal functions of the RP S19, a proapoptotic signal in pro-EBs, which is caused by mutations in the RP S19 gene, is associated with the inherited erythroblastopenia, Diamond-Blackfan anaemia. In this study, we detected C5aR expression and RP S19 oligomer generation in human erythroleukemia K562 cells during haemin-induced erythropoiesis. Under monocell culture conditions, the differentiation into K562 erythrocyte-like cells was enhanced following the overexpression of Wild-type RP S19. Conversely, the differentiation was repressed following the overexpression of mutant RP S19. An RP S19 oligomer inhibitor and a C5aR inhibitor blocked the association of the K562 basophilic EB-like cells and the THP-1 macrophage-like cells under coculture conditions. When bound to RP S19 oligomers, the C5aR may exhibit dual functions as a connector for the EB-macrophage island and as a sensor for EB differentiation in the bone marrow.

  13. Quinacrine induces apoptosis in human leukemia K562 cells via p38 MAPK-elicited BCL2 down-regulation and suppression of ERK/c-Jun-mediated BCL2L1 expression

    International Nuclear Information System (INIS)

    Changchien, Jung-Jung; Chen, Ying-Jung; Huang, Chia-Hui; Cheng, Tian-Lu; Lin, Shinne-Ren; Chang, Long-Sen

    2015-01-01

    Although previous studies have revealed the anti-cancer activity of quinacrine, its effect on leukemia is not clearly resolved. We sought to explore the cytotoxic effect and mechanism of quinacrine action in human leukemia K562 cells. Quinacrine induced K562 cell apoptosis accompanied with ROS generation, mitochondrial depolarization, and down-regulation of BCL2L1 and BCL2. Upon exposure to quinacrine, ROS-mediated p38 MAPK activation and ERK inactivation were observed in K562 cells. Quinacrine-induced cell death and mitochondrial depolarization were suppressed by the p38MAPK inhibitor SB202190 and constitutively active MEK1 over-expression. Activation of p38 MAPK was shown to promote BCL2 degradation. Further, ERK inactivation suppressed c-Jun-mediated transcriptional expression of BCL2L1. Over-expression of BCL2L1 and BCL2 attenuated quinacrine-evoked mitochondrial depolarization and rescued the viability of quinacrine-treated cells. Taken together, our data indicate that quinacrine-induced K562 cell apoptosis is mediated through mitochondrial alterations triggered by p38 MAPK-mediated BCL2 down-regulation and suppression of ERK/c-Jun-mediated BCL2L1 expression. - Highlights: • Quinacrine induces K562 cell apoptosis via down-regulation of BCL2 and BCL2L1. • Quinacrine induces p38 MAPK activation and ERK inactivation in K562 cells. • Quinacrine elicits p38 MAPK-mediated BCL2 down-regulation. • Quinacrine suppresses ERK/c-Jun-mediated BCL2L1 expression

  14. Encapsulation of Piper cabralanum (Piperaceae) nonpolar extract in poly(methyl methacrylate) by miniemulsion and evaluation of increase in the effectiveness of antileukemic activity in K562 cells.

    Science.gov (United States)

    Mendes, Anderson Nogueira; Filgueiras, Lívia Alves; Siqueira, Monica Regina Pimentel; Barbosa, Gleyce Moreno; Holandino, Carla; de Lima Moreira, Davyson; Pinto, José Carlos; Nele, Marcio

    2017-01-01

    This study aimed to synthesize and characterize nanoparticles (NPs) of poly(methyl methacrylate) (PMMA) and evaluate their ability to incorporate plant extracts with antitumor activity and low dissolution in aqueous media. The extract used was n -hexane partition of the methanol extract of Piper cabralanum (PCA-HEX). PMMA NPs were obtained using the mini-emulsion method, which was able to encapsulate almost 100% of PCA-HEX. The synthesized polymeric particles presented with a size of 200 nm and a negative charge. Cytotoxicity tests by MTT and trypan blue assays showed that NPs without PCA-HEX did not kill leukemic cells (K562 cells). NPs containing PCA-HEX were able to enhance cell death when compared to pure extract. The results showed that PMMA NPs could be useful as a drug delivery system as they can enhance the antitumor activity of the PCA-HEX extract by more than 20-fold. PMMA NPs containing plant extracts with antitumor activities may be an alternative to control the evolution of diseases such as leukemia.

  15. Silencing of BCR/ABL Chimeric Gene in Human Chronic Myelogenous Leukemia Cell Line K562 by siRNA-Nuclear Export Signal Peptide Conjugates.

    Science.gov (United States)

    Shinkai, Yasuhiro; Kashihara, Shinichi; Minematsu, Go; Fujii, Hirofumi; Naemura, Madoka; Kotake, Yojiro; Morita, Yasutaka; Ohnuki, Koichiro; Fokina, Alesya A; Stetsenko, Dmitry A; Filichev, Vyacheslav V; Fujii, Masayuki

    2017-06-01

    Herein we described the synthesis of siRNA-NES (nuclear export signal) peptide conjugates by solid phase fragment coupling and the application of them to silencing of bcr/abl chimeric gene in human chronic myelogenous leukemia cell line K562. Two types of siRNA-NES conjugates were prepared, and both sense strands at 5' ends were covalently linked to a NES peptide derived from TFIIIA and HIV-1 REV, respectively. Significant enhancement of silencing efficiency was observed for both of them. siRNA-TFIIIA NES conjugate suppressed the expression of BCR/ABL gene to 8.3% at 200 nM and 11.6% at 50 nM, and siRNA-HIV-1REV NES conjugate suppressed to 4.0% at 200 nM and 6.3% at 50 nM, whereas native siRNA suppressed to 36.3% at 200 nM and 30.2% at 50 nM. We could also show complex of siRNA-NES conjugate and designed amphiphilic peptide peptideβ7 could be taken up into cells with no cytotoxicity and showed excellent silencing efficiency. We believe that the complex siRNA-NES conjugate and peptideβ7 is a promising candidate for in vivo use and therapeutic applications.

  16. Cellular uptake, nuclear localization and cytotoxicity of 125I-labelled DNA minor groove binding ligands in K562, human erythroleukaemia cells

    International Nuclear Information System (INIS)

    Karagiannis, T.C.; Lobachevsky, P.N.; Martin, R.F.

    2000-01-01

    Full text: Iodine-125 decays by orbital electron capture and internal conversion resulting in the emission of numerous Auger electrons which produce a highly localised radiochemical damage in the immediate vicinity of the site of decay. Given the requirement to deliver 125 I to the nuclear DNA, a minor groove binding bibenzimidazole, 125 I-iodoHoechst 33258 was investigated. It has been noted that this analogue may be prone to de-iodination in vitro and in vivo, given the presence of an orthoiodophenol moiety which is analogous to that in thyroxins. Therefore, an 125 I -iodoHoechst analogue without the hydroxyl group was also studied. The 125 I -iodoHoechst 33258 analogue was prepared by direct iodination of Hoechst 33258 and 125 I iodoHoechst was prepared by demetallation of a trimethylstannyl precursor. DNA binding studies indicated that both iodo-analogues bind to calf thymus DNA, K D = 89 ± 30nM, n = 0.018 bp - 1 for iodoHoechst 33258 and K D = 121 ± 31nM, n = 0.024 bp -1 for iodoHoechst. Similarly, nuclear localization following incubation with 5μM of either ligand at 37 deg C was observed in K562 cells by fluorescence microscopy. Flow cytometry was used to investigate the kinetics of drug uptake and efflux in K562 cells. The results indicated that when 10 6 cells were incubated with 5μM ligand at 37 deg C, the uptake reached a plateau at approximately 43 minutes for iodoHoechst 33258 and approximately 52 minutes for iodoHoechst. Ligand efflux results indicated two-phase kinetics. The initial phase which involves 50-60% of drug was characterised by a half-life time (t 1/2 ) of 55.4 minutes for efflux of iodoHoechst 33258 and a t 1/2 of 10.3 minutes for efflux of iodoHoechst, at 37 deg C. Furthermore, the results suggested that the DNA binding sites in a 10 6 cell/ml suspension were saturated by incubation with 3μM iodoHoechst 33258 and 5μM iodoHoechst. In the initial cytotoxicity experiments using 125 I-iodoHoechst 33258, K562 cells were incubated for 1

  17. Photodynamic treatment (ALA-PDT) suppresses the expression of the oncogenic Bcr-Abl kinase and affects the cytoskeleton organization in K562 cells

    Czech Academy of Sciences Publication Activity Database

    Pluskalová, M.; Pešlová, G.; Grebeňová, D.; Halada, Petr; Hrkal, Z.

    2006-01-01

    Roč. 83, - (2006), s. 205-212 ISSN 1011-1344 R&D Projects: GA MZd NL7681 Institutional research plan: CEZ:AV0Z50200510 Keywords : k562 * bcr -abl * photodynamic treatment Subject RIV: EE - Microbiology, Virology Impact factor: 1.909, year: 2006

  18. Stat5 Exerts Distinct, Vital Functions in the Cytoplasm and Nucleus of Bcr-Abl{sup +} K562 and Jak2(V617F){sup +} HEL Leukemia Cells

    Energy Technology Data Exchange (ETDEWEB)

    Weber, Axel [Georg-Speyer-Haus, Institute for Tumor Biology and Experimental Therapy, Frankfurt am Main 60596 (Germany); Borghouts, Corina [Ganymed Pharmaceuticals AG, Mainz 55131 (Germany); Brendel, Christian [Boston Children’s Hospital, Division of Hematology/Oncology, Boston, MA 02115 (United States); Moriggl, Richard [Ludwig Boltzmann Institute for Cancer Research (LBI-CR), Vienna 1090 (Austria); Delis, Natalia; Brill, Boris; Vafaizadeh, Vida; Groner, Bernd, E-mail: Groner@em.uni-frankfurt.de [Georg-Speyer-Haus, Institute for Tumor Biology and Experimental Therapy, Frankfurt am Main 60596 (Germany)

    2015-03-19

    Signal transducers and activators of transcription (Stats) play central roles in the conversion of extracellular signals, e.g., cytokines, hormones and growth factors, into tissue and cell type specific gene expression patterns. In normal cells, their signaling potential is strictly limited in extent and duration. The persistent activation of Stat3 or Stat5 is found in many human tumor cells and contributes to their growth and survival. Stat5 activation plays a pivotal role in nearly all hematological malignancies and occurs downstream of oncogenic kinases, e.g., Bcr-Abl in chronic myeloid leukemias (CML) and Jak2(V617F) in other myeloproliferative diseases (MPD). We defined the mechanisms through which Stat5 affects growth and survival of K562 cells, representative of Bcr-Abl positive CML, and HEL cells, representative for Jak2(V617F) positive acute erythroid leukemia. In our experiments we suppressed the protein expression levels of Stat5a and Stat5b through shRNA mediated downregulation and demonstrated the dependence of cell survival on the presence of Stat5. Alternatively, we interfered with the functional capacities of the Stat5 protein through the interaction with a Stat5 specific peptide ligand. This ligand is a Stat5 specific peptide aptamer construct which comprises a 12mer peptide integrated into a modified thioredoxin scaffold, S5-DBD-PA. The peptide sequence specifically recognizes the DNA binding domain (DBD) of Stat5. Complex formation of S5-DBD-PA with Stat5 causes a strong reduction of P-Stat5 in the nuclear fraction of Bcr-Abl-transformed K562 cells and a suppression of Stat5 target genes. Distinct Stat5 mediated survival mechanisms were detected in K562 and Jak2(V617F)-transformed HEL cells. Stat5 is activated in the nuclear and cytosolic compartments of K562 cells and the S5-DBD-PA inhibitor most likely affects the viability of Bcr-Abl{sup +} K562 cells through the inhibition of canonical Stat5 induced target gene transcription. In HEL cells

  19. Structural Characteristics of the Novel Polysaccharide FVPA1 from Winter Culinary-Medicinal Mushroom, Flammulina velutipes (Agaricomycetes), Capable of Enhancing Natural Killer Cell Activity against K562 Tumor Cells.

    Science.gov (United States)

    Jia, Wei; Feng, Jie; Zhang, Jing-Song; Lin, Chi-Chung; Wang, Wen-Han; Chen, Hong-Ge

    2017-01-01

    FVPA1, a novel polysaccharide, has been isolated from fruiting bodies of the culinary-medicinal mushroom Flammulina velutipes, a historically popular, widely cultivated and consumed functional food with an attractive taste, beneficial nutraceutical properties such as antitumor and immunomodulatory effects, and a number of essential biological activities. The average molecular weight was estimated to be ~1.8 × 104 Da based on high-performance size exclusion chromatography. Sugar analyses, methylation analyses, and 1H, 13C, and 2-dimensional nuclear magnetic resonance spectroscopy revealed the following structure of the repeating units of the FVPA1 polysaccharide Identification of this structure would conceivably lead to better understanding of the nutraceutical functions of this very important edible fungus. Bioactivity tests in vitro indicated that FVPA1 could significantly enhance natural killer cell activity against K562 tumor cells.

  20. In Vitro Characterization and Evaluation of the Cytotoxicity Effects of Nisin and Nisin-Loaded PLA-PEG-PLA Nanoparticles on Gastrointestinal (AGS and KYSE-30), Hepatic (HepG2) and Blood (K562) Cancer Cell Lines.

    Science.gov (United States)

    Goudarzi, Fariba; Asadi, Asadollah; Afsharpour, Maryam; Jamadi, Robab Hassanvand

    2018-05-01

    The aim of this study was an in vitro evaluation and comparison of the cytotoxic effects of free nisin and nisin-loaded PLA-PEG-PLA nanoparticles on gastrointestinal (AGS and KYSE-30), hepatic (HepG2), and blood (K562) cancer cell lines. To create this novel anti-cancer drug delivery system, the nanoparticles were synthesized and then loaded with nisin. Subsequently, their biocompatibility, ability to enter cells, and physicochemical properties, including formation, size, and shape, were studied using hemolysis, fluorescein isothiocyanate (FITC), Fourier transform infrared (FTIR) spectroscopy, dynamic light scattering (DLS), and scanning electron microscopy (SEM), respectively. Then, its loading efficiency and release kinetics were examined to assess the potential impact of this formulation for the nanoparticle carrier candidacy. The cytotoxicities of nisin and nisin-loaded nanoparticles were evaluated by using the MTT and Neutral Red (NR) uptake assays. Detections of the apoptotic cells were done via Ethidium Bromide (EB)/Acridine Orange (AO) staining. The FTIR spectra, SEM images, and DLS graph confirmed the formations of the nanoparticles and nisin-loaded nanoparticles with spherical, distinct, and smooth surfaces and average sizes of 100 and 200 nm, respectively. The loading efficiency of the latter nanoparticles was about 85-90%. The hemolysis test represented their non-cytotoxicities and the FITC images indicated their entrance inside the cells. An increase in the percentage of apoptotic cells was observed through EB/AO staining. These results demonstrated that nisin had a cytotoxic effect on AGS, KYSE-30, HepG2, and K562 cancer cell lines, while the cytotoxicity of nisin-loaded nanoparticles was more than that of the free nisin.

  1. Luteoloside Inhibits Proliferation of Human Chronic Myeloid ...

    African Journals Online (AJOL)

    Purpose: To investigate the effects of luteoloside on the proliferation of human chronic myeloid leukemia K562 cells and whether luteoloside induces cell cycle arrest and apoptosis in K562 cells. Methods: Luteoloside's cytotoxicity was assessed using a cell counting kit. Cell cycle distribution was analysed by flow cytometry ...

  2. Role of glycolysis inhibition and poly(ADP-ribose) polymerase activation in necrotic-like cell death caused by ascorbate/menadione-induced oxidative stress in K562 human chronic myelogenous leukemic cells.

    Science.gov (United States)

    Verrax, Julien; Vanbever, Stéphanie; Stockis, Julie; Taper, Henryk; Calderon, Pedro Buc

    2007-03-15

    Among different features of cancer cells, two of them have retained our interest: their nearly universal glycolytic phenotype and their sensitivity towards an oxidative stress. Therefore, we took advantage of these features to develop an experimental approach by selectively exposing cancer cells to an oxidant insult induced by the combination of menadione (vitamin K(3)) and ascorbate (vitamin C). Ascorbate enhances the menadione redox cycling, increases the formation of reactive oxygen species and kills K562 cells as shown by more than 65% of LDH leakage after 24 hr of incubation. Since both lactate formation and ATP content are depressed by about 80% following ascorbate/menadione exposure, we suggest that the major intracellular event involved in such a cytotoxicity is related to the impairment of glycolysis. Indeed, NAD(+) is rapidly and severely depleted, a fact most probably related to a strong Poly(ADP-ribose) polymerase (PARP) activation, as shown by the high amount of poly-ADP-ribosylated proteins. The addition of N-acetylcysteine (NAC) restores most of the ATP content and the production of lactate as well. The PARP inhibitor dihydroxyisoquinoline (DiQ) was able to partially restore both parameters as well as cell death induced by ascorbate/menadione. These results suggest that the PARP activation induced by the oxidative stress is a major but not the only intracellular event involved in cell death by ascorbate/menadione. Due to the high energetic dependence of cancer cells on glycolysis, the impairment of such an essential pathway may explain the effectiveness of this combination to kill cancer cells. (c) 2006 Wiley-Liss, Inc.

  3. RPS27a promotes proliferation, regulates cell cycle progression and inhibits apoptosis of leukemia cells

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Houcai; Yu, Jing; Zhang, Lixia; Xiong, Yuanyuan; Chen, Shuying; Xing, Haiyan; Tian, Zheng; Tang, Kejing; Wei, Hui; Rao, Qing; Wang, Min; Wang, Jianxiang, E-mail: wangjx@ihcams.ac.cn

    2014-04-18

    Highlights: • RPS27a expression was up-regulated in advanced-phase CML and AL patients. • RPS27a knockdown changed biological property of K562 and K562/G01 cells. • RPS27a knockdown affected Raf/MEK/ERK, P21 and BCL-2 signaling pathways. • RPS27a knockdown may be applicable for new combination therapy in CML patients. - Abstract: Ribosomal protein S27a (RPS27a) could perform extra-ribosomal functions besides imparting a role in ribosome biogenesis and post-translational modifications of proteins. The high expression level of RPS27a was reported in solid tumors, and we found that the expression level of RPS27a was up-regulated in advanced-phase chronic myeloid leukemia (CML) and acute leukemia (AL) patients. In this study, we explored the function of RPS27a in leukemia cells by using CML cell line K562 cells and its imatinib resistant cell line K562/G01 cells. It was observed that the expression level of RPS27a was high in K562 cells and even higher in K562/G01 cells. Further analysis revealed that RPS27a knockdown by shRNA in both K562 and K562G01 cells inhibited the cell viability, induced cell cycle arrest at S and G2/M phases and increased cell apoptosis induced by imatinib. Combination of shRNA with imatinib treatment could lead to more cleaved PARP and cleaved caspase-3 expression in RPS27a knockdown cells. Further, it was found that phospho-ERK(p-ERK) and BCL-2 were down-regulated and P21 up-regulated in RPS27a knockdown cells. In conclusion, RPS27a promotes proliferation, regulates cell cycle progression and inhibits apoptosis of leukemia cells. It appears that drugs targeting RPS27a combining with tyrosine kinase inhibitor (TKI) might represent a novel therapy strategy in TKI resistant CML patients.

  4. CLEC4M慢病毒载体的构建及其在K562细胞中的表达

    Directory of Open Access Journals (Sweden)

    WANG Yuanyuan

    2014-06-01

    Full Text Available ObjectiveTo construct the lentiviral vector encoding CLEC4M and prepare K-562 cells with stable overexpression of CLEC4M. MethodsThe gene sequence of normal CLEC4M was cloned by RT-PCR and then inserted into GV166 vector to construct GV166-CLEC4M lentiviral expression vector, and then lentiviral packaging was performed by transfection of 293T cells. The obtained lentiviral liquid was used to infect human leukemia cell line K-562. Real-time PCR and Western blot were used to detect the overexpression of CLEC4M in K-562 cells. ResultsSequencing showed that the recombinant lentiviral expression plasmid GV166-CLEC4M was successfully constructed. Lentiviruses could efficiently infect K-562 cells, according to real-time PCR. CLEC4M was successfully over-expressed in K-562 cells at mRNA and protein levels. ConclusionThe construction of lentiviral vector encoding CLEC4M lays a foundation for further study of CLEC4M gene involved in HCV entry into host cells.

  5. In vitro studies of ante-mortem proliferation kinetics

    International Nuclear Information System (INIS)

    McBride, W.H.; Withers, H.R.

    1986-01-01

    Using K562 human erythroblastoid cells, it was concluded that dose fractionation has no discrepant effect on the ante-mortem proliferation kinetics of doomed cells as opposed to clonogenic cell survival and that effects on ante-mortem proliferation kinetics cannot be solely responsible for the differences in fractionation response between early and late responding tissues. (UK)

  6. Eurycomanone and Eurycomanol from Eurycoma longifolia Jack as Regulators of Signaling Pathways Involved in Proliferation, Cell Death and Inflammation

    Directory of Open Access Journals (Sweden)

    Shéhérazade Hajjouli

    2014-09-01

    Full Text Available Eurycomanone and eurycomanol are two quassinoids from the roots of Eurycoma longifolia Jack. The aim of this study was to assess the bioactivity of these compounds in Jurkat and K562 human leukemia cell models compared to peripheral blood mononuclear cells from healthy donors. Both eurycomanone and eurycomanol inhibited Jurkat and K562 cell viability and proliferation without affecting healthy cells. Interestingly, eurycomanone inhibited NF-κB signaling through inhibition of IκBα phosphorylation and upstream mitogen activated protein kinase (MAPK signaling, but not eurycomanol. In conclusion, both quassinoids present differential toxicity towards leukemia cells, and the presence of the α,β-unsaturated ketone in eurycomanone could be prerequisite for the NF-κB inhibition.

  7. Cell Proliferation in Neuroblastoma

    Science.gov (United States)

    Stafman, Laura L.; Beierle, Elizabeth A.

    2016-01-01

    Neuroblastoma, the most common extracranial solid tumor of childhood, continues to carry a dismal prognosis for children diagnosed with advanced stage or relapsed disease. This review focuses upon factors responsible for cell proliferation in neuroblastoma including transcription factors, kinases, and regulators of the cell cycle. Novel therapeutic strategies directed toward these targets in neuroblastoma are discussed. PMID:26771642

  8. Analysis of the role of COP9 Signalosome (CSN subunits in K562; the first link between CSN and autophagy

    Directory of Open Access Journals (Sweden)

    Bunce Christopher M

    2009-04-01

    Full Text Available Abstract Background The COP9/signalosome (CSN is a highly conserved eight subunit complex that, by deneddylating cullins in cullin-based E3 ubiquitin ligases, regulates protein degradation. Although studied in model human cell lines such as HeLa, very little is known about the role of the CSN in haemopoietic cells. Results Greater than 95% knockdown of the non-catalytic subunit CSN2 and the deneddylating subunit CSN5 of the CSN was achieved in the human myeloid progenitor cell line K562. CSN2 knockdown led to a reduction of both CSN5 protein and mRNA whilst CSN5 knockdown had little effect on CSN2. Both knockdowns inhibited CSN deneddylase function as demonstrated by accumulation of neddylated Cul1. Furthermore, both knockdowns resulted in the sequential loss of Skp2, Cdc4 and β-TrCP F-box proteins. These proteins were rescued by the proteasome inhibitor MG132, indicating the autocatalytic degradation of F-box proteins upon loss of CSN2 or CSN5. Interestingly, altered F-box protein gene expression was also observed in CSN2 and CSN5 knockdowns, suggesting a potential role of the CSN in regulating F-box protein transcription. Loss of either CSN subunit dramatically reduced cell growth but resulted in distinct patterns of cell death. CSN5 knockdown caused mitotic defects, G2/M arrest and apoptotic cell death. CSN2 knockdown resulted in non-apoptotic cell death associated with accumulation of both the autophagy marker LC3-II and autophagic vacuoles. Treatment of vector control K562 cells with the autophagy inhibitors 3-methyladenine and bafilomycin A1 recapitulated the growth kinetics, vacuolar morphology and LC3-II accumulation of CSN2 knockdown cells indicating that the cellular phenotype of CSN2 cells arises from autophagy inhibition. Finally, loss of CSN2 was associated with the formation of a CSN5 containing subcomplex. Conclusion We conclude that CSN2 is required for CSN integrity and the stability of individual CSN subunits, and postulate

  9. Overcoming imatinib resistance using Src inhibitor CGP76030, Abl inhibitor nilotinib and Abl/Lyn inhibitor INNO-406 in newly established K562 variants with BCR-ABL gene amplification.

    Science.gov (United States)

    Morinaga, Koji; Yamauchi, Takahiro; Kimura, Shinya; Maekawa, Taira; Ueda, Takanori

    2008-06-01

    Because imatinib (IM) resistance in chronic myeloid leukemia is primarily caused by the re-establishment of Abl kinase, new inhibitors may be efficacious. We evaluated 3 new agents against 2 new K562 variants, IM-R1 and IM-R2 cells, which were developed having 7- and 27-fold greater IM resistance, respectively, than the parental K562 cells. Both variants possessed BCR-ABL gene amplification along with elevated levels of its transcript and protein. Greater BCR-ABL gene amplification was observed in IM-R2 cells than in IM-R1 cells, which was consistent with the higher mRNA and protein levels of Bcr-Abl, and ultimately correlated with the greater IM resistance in IM-R2 cells. No mutation in the Abl kinase domain was detected in either variant. Despite the absence of Lyn overexpression, the Src kinase inhibitor CGP76030 showed positive cooperability with IM in inhibiting cell growth of not only K562 cells but also these 2 variants. This might be because of the augmented inhibition of Erk1/2 phosphorylation. The new Abl kinase inhibitor nilotinib was 10-fold more potent than IM in inhibiting the growth of K562 cells. Nilotinib inhibited the growth of IM-R1 and IM-R2 cells as potently as K562 cells. The combination of nilotinib with CGP76030 showed little additivity, because the potency of nilotinib masked the efficacy of CGP76030. The new dual Abl/Lyn inhibitor INNO-406 (formerly NS-187) was slightly more potent than nilotinib in inhibiting the growth of all 3 cell lines. Because BCR-ABL gene amplification occurs in blast crisis, these inhibitors might overcome IM resistance in such patients' leukemia. (c) 2008 Wiley-Liss, Inc.

  10. Expression of p89c-Mybex9b, an alternatively spliced form of c-Myb, is required for proliferation and survival of p210BCR/ABL-expressing cells

    International Nuclear Information System (INIS)

    Manzotti, G; Mariani, S A; Corradini, F; Bussolari, R; Cesi, V; Vergalli, J; Ferrari-Amorotti, G; Fragliasso, V; Soliera, A R; Cattelani, S; Raschellà, G; Holyoake, T L; Calabretta, B

    2012-01-01

    The c-Myb gene encodes the p75 c-Myb isoform and less-abundant proteins generated by alternatively spliced transcripts. Among these, the best known is p c-Mybex9b , which contains 121 additional amino acids between exon 9 and 10, in a domain involved in protein–protein interactions and negative regulation. In hematopoietic cells, expression of p c-Mybex9b accounts for 10–15% of total c-Myb; these levels may be biologically relevant because modest changes in c-Myb expression affects proliferation and survival of leukemic cells and lineage choice and frequency of normal hematopoietic progenitors. In this study, we assessed biochemical activities of p c-Mybex9b and the consequences of perturbing its expression in K562 and primary chronic myeloid leukemia (CML) progenitor cells. Compared with p75 c-Myb , p c-Mybex9b is more stable and more effective in transactivating Myb-regulated promoters. Ectopic expression of p c-Mybex9b enhanced proliferation and colony formation and reduced imatinib (IM) sensitivity of K562 cells; conversely, specific downregulation of p c-Mybex9b reduced proliferation and colony formation, enhanced IM sensitivity of K562 cells and markedly suppressed colony formation of CML CD34 + cells, without affecting the levels of p75 c-Myb . Together, these studies indicate that expression of the low-abundance p c-Mybex9b isoform has an important role for the overall biological effects of c-Myb in BCR/ABL-transformed cells

  11. A comparison of cytotoxicity of some phosphoramides against K562 cell line

    Directory of Open Access Journals (Sweden)

    niloufar Dorosti

    2012-03-01

    Conclusion: Since hydrogen bonds play a key role in biology processes, these results suggest that increase in the hydrogen bonds of derivatives bearing urea moiety (4-6 may be increase cytotoxicity of these compounds. Moreover, the 3-NO2 group showed higher anti-cancer activity than two other positions owing to possibility electronic and steric effects.

  12. Effects of antioxidants on apoptosis induced by dasatinib and nilotinib in K562 cells.

    Science.gov (United States)

    Damiano, Sara; Montagnaro, Serena; Puzio, Maria V; Severino, Lorella; Pagnini, Ugo; Barbarino, Marcella; Cesari, Daniele; Giordano, Antonio; Florio, Salvatore; Ciarcia, Roberto

    2018-06-01

    In clinical practice for the treatment of chronic myeloid leukemia, second generation of tyrosine kinase inhibitors such as Nilotinib (NIL) specific and potent inhibitor of the BCR/ABL kinase and Dasatinib (DAS) a inhibitor of BCR/ABL and Src family kinase were developed to clinically overcome imatinib resistance. In this study, we wanted to test the ability of some antioxidants such Resveratrol (RES) or a new recombinant mitochondrial manganese containing superoxide dismutase (rMnSOD) or δ-tocotrienol (δ-TOCO) to interact with DAS and NIL on viability, reactive oxygen species (ROS) production, lipid peroxidation, and apoptosis. To test the possible mechanisms of action of such antioxidants, we utilized N-acetyl-L-cysteine (NAC) a specific inhibitor ROS production or PP1 a specific Src tyrosine kinase inhibitor or BAPTA a specific chelator of intracellular calcium. Our data demonstrated: 1) RES, rMnSOD, δ-TOCO, and NAC, at dose used, significantly reduced the intracellular levels of MDA induced by DAS or NIL; 2) RES, rMnSOD, and δ-TOCO increased the intracellular ROS levels; 3) The increase ROS levels is related to higher levels of oligonucleosomesi induced by DAS and NIL and that NAC significantly reduced this activity. Interestingly, our data showed that apoptotic activity of DAS and NIL have significantly increased the production of oligonucleosomes by triggering excessive ROS generation as well as functionality of SERCA receptors. © 2018 Wiley Periodicals, Inc.

  13. Neural control of colonic cell proliferation.

    Science.gov (United States)

    Tutton, P J; Barkla, D H

    1980-03-15

    The mitotic rate in rat colonic crypts and in dimethylhydrazine-induced colonic carcinomas was measured using a stathmokinetic technique. In sympathectomized animals cell proliferation was retarded in the crypts but not in the tumors, whereas in animals treated with Metaraminol, a drug which releases norepinephrine from nerve terminals, crypt cell but not tumor cell proliferation was accelerated. Blockade of alpha-adrenoceptors also inhibited crypt cell proliferation. However, stimulation of beta-adrenoceptors inhibited and blockade of beta-adrenoceptors accelerated tumor cell proliferation without influencing crypt cell proliferation. Injection of either serotonin or histamine stimulated tumor but not crypt cell proliferation and blockade or serotonin receptors or histamine H2-receptors inhibited tumor cell proliferation. It is postulated that cell proliferation in the colonic crypts, like that in the jejunal crypts, is under both endocrine and autonomic neural control whereas colonic tumor cell division is subject to endocrine regulation alone.

  14. Nanoparticles for cells proliferation enhancement

    International Nuclear Information System (INIS)

    Popa, V.; Braniste, F.; Tiginyanu, I.M.; Lisii, C.; Nacu, V.

    2013-01-01

    The potential of semiconductor nanoparticles as stimulator for avian mesenchyme stem cells proliferation enhancement is demonstrated. The effect is related to nanoparticles polarization due to external ultrasound field resulting in local electrical stimulation. Our preliminary results demonstrates that the number of cells have been increased by 23 % ±2%) in cell cultures under the action of external ultrasound stimulation. Morphological analysis and viability shows no differences between the control group and the group studied. These results suggest the possibility for tissue regeneration enhancement by remote stimulation of implanted semiconductor nanoparticles. (authors)

  15. Apoptosis induced by (di-isopropyloxyphoryl-Trp) -Lys-OCH in K562 ...

    Indian Academy of Sciences (India)

    PRAKASH KUMAR G

    Rational drug development in cancer therapy appears to ... at this point, resulting in the treated cells entering into programmed cell death. ... foetal bovine serum; IC50, inhibitory concentration 50%; IR%, inhibition rate; MTT, .... negative) from the late apoptotic cells (annexin V-positive .... Results are representative of three.

  16. SPARC expression in CML is associated to imatinib treatment and to inhibition of leukemia cell proliferation

    International Nuclear Information System (INIS)

    Giallongo, Cesarina; Palumbo, Giuseppe A; Di Raimondo, Francesco; La Cava, Piera; Tibullo, Daniele; Barbagallo, Ignazio; Parrinello, Nunziatina; Cupri, Alessandra; Stagno, Fabio; Consoli, Carla; Chiarenza, Annalisa

    2013-01-01

    SPARC is a matricellular glycoprotein with growth-inhibitory and antiangiogenic activity in some cell types. The study of this protein in hematopoietic malignancies led to conflicting reports about its role as a tumor suppressor or promoter, depending on its different functions in the tumor microenvironment. In this study we investigated the variations in SPARC production by peripheral blood cells from chronic myeloid leukemia (CML) patients at diagnosis and after treatment and we identified the subpopulation of cells that are the prevalent source of SPARC. We evaluated SPARC expression using real-time PCR and western blotting. SPARC serum levels were detected by ELISA assay. Finally we analyzed the interaction between exogenous SPARC and imatinib (IM), in vitro, using ATP-lite and cell cycle analysis. Our study shows that the CML cells of patients at diagnosis have a low mRNA and protein expression of SPARC. Low serum levels of this protein are also recorded in CML patients at diagnosis. However, after IM treatment we observed an increase of SPARC mRNA, protein, and serum level in the peripheral blood of these patients that had already started at 3 months and was maintained for at least the 18 months of observation. This SPARC increase was predominantly due to monocyte production. In addition, exogenous SPARC protein reduced the growth of K562 cell line and synergized in vitro with IM by inhibiting cell cycle progression from G1 to S phase. Our results suggest that low endogenous SPARC expression is a constant feature of BCR/ABL positive cells and that IM treatment induces SPARC overproduction by normal cells. This exogenous SPARC may inhibit CML cell proliferation and may synergize with IM activity against CML

  17. SPARC expression in CML is associated to imatinib treatment and to inhibition of leukemia cell proliferation

    Directory of Open Access Journals (Sweden)

    Giallongo Cesarina

    2013-02-01

    Full Text Available Abstract Background SPARC is a matricellular glycoprotein with growth-inhibitory and antiangiogenic activity in some cell types. The study of this protein in hematopoietic malignancies led to conflicting reports about its role as a tumor suppressor or promoter, depending on its different functions in the tumor microenvironment. In this study we investigated the variations in SPARC production by peripheral blood cells from chronic myeloid leukemia (CML patients at diagnosis and after treatment and we identified the subpopulation of cells that are the prevalent source of SPARC. Methods We evaluated SPARC expression using real-time PCR and western blotting. SPARC serum levels were detected by ELISA assay. Finally we analyzed the interaction between exogenous SPARC and imatinib (IM, in vitro, using ATP-lite and cell cycle analysis. Results Our study shows that the CML cells of patients at diagnosis have a low mRNA and protein expression of SPARC. Low serum levels of this protein are also recorded in CML patients at diagnosis. However, after IM treatment we observed an increase of SPARC mRNA, protein, and serum level in the peripheral blood of these patients that had already started at 3 months and was maintained for at least the 18 months of observation. This SPARC increase was predominantly due to monocyte production. In addition, exogenous SPARC protein reduced the growth of K562 cell line and synergized in vitro with IM by inhibiting cell cycle progression from G1 to S phase. Conclusion Our results suggest that low endogenous SPARC expression is a constant feature of BCR/ABL positive cells and that IM treatment induces SPARC overproduction by normal cells. This exogenous SPARC may inhibit CML cell proliferation and may synergize with IM activity against CML.

  18. Blocking the proliferation of human tumor cell lines by peptidase inhibitors from Bauhinia seeds.

    Science.gov (United States)

    Nakahata, Adriana Miti; Mayer, Barbara; Neth, Peter; Hansen, Daiane; Sampaio, Misako Uemura; Oliva, Maria Luiza Vilela

    2013-03-01

    In cancer tumors, growth, invasion, and formation of metastasis at a secondary site play a pivotal role, participating in diverse processes in the development of the pathology, such as degradation of extracellular matrix. Bauhinia seeds contain relatively large quantities of peptidase inhibitors, and two Bauhinia inhibitors were obtained in a recombinant form from the Bauhinia bauhinioides species, B. bauhinoides cruzipain inhibitor, which is a cysteine and serine peptidase inhibitor, and B. bauhinioides kallikrein inhibitor, which is a serine peptidase inhibitor. While recombinant B. bauhinoides cruzipain inhibitor inhibits human neutrophil elastase cathepsin G and the cysteine proteinase cathepsin L, recombinant B. bauhinioides kallikrein inhibitor inhibits plasma kallikrein and plasmin. The effects of recombinant B. bauhinoides cruzipain inhibitor and recombinant B. bauhinioides kallikrein inhibitor on the viability of tumor cell lines with a distinct potential of growth from the same tissue were compared to those of the clinical cytotoxic drug 5-fluorouracil. At 12.5 µM concentration, recombinant B. bauhinoides cruzipain inhibitor and recombinant B. bauhinioides kallikrein inhibitor were more efficient than 5-fluorouracil in inhibiting MKN-28 and Hs746T (gastric), HCT116 and HT29 (colorectal), SkBr-3 and MCF-7 (breast), and THP-1 and K562 (leukemia) cell lines. Additionally, recombinant B. bauhinoides cruzipain inhibitor inhibited 40 % of the migration of Hs746T, the most invasive gastric cell line, while recombinant B. bauhinioides kallikrein inhibitor did not affect cell migration. Recombinant B. bauhinioides kallikrein inhibitor and recombinant B. bauhinoides cruzipain inhibitor, even at high doses, did not affect hMSC proliferation while 5-fluorouracil greatly reduced the proliferation rates of hMSCs. Therefore, both recombinant B. bauhinoides cruzipain inhibitor and recombinant B. bauhinioides kallikrein inhibitor might be considered for further studies

  19. Characterization of Compounds with Tumor-Cell Proliferation Inhibition Activity from Mushroom (Phellinus baumii) Mycelia Produced by Solid-State Fermentation.

    Science.gov (United States)

    Zhang, Henan; Shao, Qian; Wang, Wenhan; Zhang, Jingsong; Zhang, Zhong; Liu, Yanfang; Yang, Yan

    2017-04-27

    The inhibition of tumor-cell proliferationbyan organicsolvent extract from the solid-state fermentation of Phellinus baumii mycelia inoculated in rice medium was investigated in vitro. The active compounds inhibiting tumor-cell proliferation were characterized. Results revealed that all (petroleum ether, chloroform, ethyl acetate, and butanol) fractions inhibited tumor-cell proliferation in a dose-dependent fashion. The ethyl acetate extract had the highest inhibitory effecton tumor-cell proliferation, and the butanol fraction had the lowest. Six compounds were isolated and purified from the ethyl acetate extract of P. baumii mycelia by the tandem application of silica-gel column chromatography (SGCC), high-speed countercurrent chromatography (HSCCC), and preparative HPLC. These compounds were identified by NMR and electrospray ionization-mass spectrometry (ESI-MS) spectroscopic methods as ergosterol (RF1), ergosta-7,22-dien-3β-yl pentadecanoate (RF3), 3,4-dihydroxy benzaldehyde(RF6), inoscavinA (RF7), baicalein(RF10), and 24-ethylcholesta-5,22-dien-3β-ol (RF13). To further clarify the activity of these compounds, the cell-proliferation-inhibition tests of these compounds on various tumor cells were carried out and evaluatedin vitro. Results suggested that compounds RF6, RF7, and RF10 had potent inhibition effects on the proliferation of a series of tumor cell lines, including K562, L1210, SW620, HepG2, LNCaP, and MCF-7cells. These findings indicated that P. baumii mycelia produced by solid-state fermentation in rice canbe used to obtain active compounds with the ability to inhibittumor-cell proliferation.

  20. Characterization of Compounds with Tumor–Cell Proliferation Inhibition Activity from Mushroom (Phellinus baumii Mycelia Produced by Solid-State Fermentation

    Directory of Open Access Journals (Sweden)

    Henan Zhang

    2017-04-01

    Full Text Available The inhibition of tumor-cell proliferationbyan organicsolvent extract from the solid-state fermentation of Phellinus baumii mycelia inoculated in rice medium was investigated in vitro. The active compounds inhibiting tumor-cell proliferation were characterized. Results revealed that all (petroleum ether, chloroform, ethyl acetate, and butanol fractions inhibited tumor-cell proliferation in a dose-dependent fashion. The ethyl acetate extract had the highest inhibitory effecton tumor-cell proliferation, and the butanol fraction had the lowest. Six compounds were isolated and purified from the ethyl acetate extract of P. baumii mycelia by the tandem application of silica-gel column chromatography (SGCC, high-speed countercurrent chromatography (HSCCC, and preparative HPLC. These compounds were identified by NMR and electrospray ionization-mass spectrometry (ESI-MS spectroscopic methods as ergosterol (RF1, ergosta-7,22-dien-3β-yl pentadecanoate (RF3, 3,4-dihydroxy benzaldehyde(RF6, inoscavinA (RF7, baicalein(RF10, and 24-ethylcholesta-5,22-dien-3β-ol (RF13. To further clarify the activity of these compounds, the cell-proliferation-inhibition tests of these compounds on various tumor cells were carried out and evaluatedin vitro. Results suggested that compounds RF6, RF7, and RF10 had potent inhibition effects on the proliferation of a series of tumor cell lines, including K562, L1210, SW620, HepG2, LNCaP, and MCF-7cells. These findings indicated that P. baumii mycelia produced by solid-state fermentation in rice canbe used to obtain active compounds with the ability to inhibittumor-cell proliferation.

  1. Expression profile of CREB knockdown in myeloid leukemia cells

    International Nuclear Information System (INIS)

    Pellegrini, Matteo; Cheng, Jerry C; Voutila, Jon; Judelson, Dejah; Taylor, Julie; Nelson, Stanley F; Sakamoto, Kathleen M

    2008-01-01

    The cAMP Response Element Binding Protein, CREB, is a transcription factor that regulates cell proliferation, differentiation, and survival in several model systems, including neuronal and hematopoietic cells. We demonstrated that CREB is overexpressed in acute myeloid and leukemia cells compared to normal hematopoietic stem cells. CREB knockdown inhibits leukemic cell proliferation in vitro and in vivo, but does not affect long-term hematopoietic reconstitution. To understand downstream pathways regulating CREB, we performed expression profiling with RNA from the K562 myeloid leukemia cell line transduced with CREB shRNA. By combining our expression data from CREB knockdown cells with prior ChIP data on CREB binding we were able to identify a list of putative CREB regulated genes. We performed extensive analyses on the top genes in this list as high confidence CREB targets. We found that this list is enriched for genes involved in cancer, and unexpectedly, highly enriched for histone genes. Furthermore, histone genes regulated by CREB were more likely to be specifically expressed in hematopoietic lineages. Decreased expression of specific histone genes was validated in K562, TF-1, and primary AML cells transduced with CREB shRNA. We have identified a high confidence list of CREB targets in K562 cells. These genes allow us to begin to understand the mechanisms by which CREB contributes to acute leukemia. We speculate that regulation of histone genes may play an important role by possibly altering the regulation of DNA replication during the cell cycle

  2. 7-Piperazinethylchrysin inhibits melanoma cell proliferation by ...

    African Journals Online (AJOL)

    In B16F10 and A375 cells, treatment with PEC caused the inhibition ... Conclusion: PEC inhibited melanoma cell proliferation, apparently by blocking the cell cycle at G0/G1 .... all statistical analyses. .... Financial support from the Department of.

  3. Induction of erythroid differentiation in human erythroleukemia cells by depletion of malic enzyme 2.

    Directory of Open Access Journals (Sweden)

    Jian-Guo Ren

    2010-09-01

    Full Text Available Malic enzyme 2 (ME2 is a mitochondrial enzyme that catalyzes the conversion of malate to pyruvate and CO2 and uses NAD as a cofactor. Higher expression of this enzyme correlates with the degree of cell de-differentiation. We found that ME2 is expressed in K562 erythroleukemia cells, in which a number of agents have been found to induce differentiation either along the erythroid or the myeloid lineage. We found that knockdown of ME2 led to diminished proliferation of tumor cells and increased apoptosis in vitro. These findings were accompanied by differentiation of K562 cells along the erythroid lineage, as confirmed by staining for glycophorin A and hemoglobin production. ME2 knockdown also totally abolished growth of K562 cells in nude mice. Increased ROS levels, likely reflecting increased mitochondrial production, and a decreased NADPH/NADP+ ratio were noted but use of a free radical scavenger to decrease inhibition of ROS levels did not reverse the differentiation or apoptotic phenotype, suggesting that ROS production is not causally involved in the resultant phenotype. As might be expected, depletion of ME2 induced an increase in the NAD+/NADH ratio and ATP levels fell significantly. Inhibition of the malate-aspartate shuttle was insufficient to induce K562 differentiation. We also examined several intracellular signaling pathways and expression of transcription factors and intermediate filament proteins whose expression is known to be modulated during erythroid differentiation in K562 cells. We found that silencing of ME2 leads to phospho-ERK1/2 inhibition, phospho-AKT activation, increased GATA-1 expression and diminished vimentin expression. Metabolomic analysis, conducted to gain insight into intermediary metabolic pathways that ME2 knockdown might affect, showed that ME2 depletion resulted in high orotate levels, suggesting potential impairment of pyrimidine metabolism. Collectively our data point to ME2 as a potentially novel

  4. Proliferating cell nuclear antigen (PCNA): a new marker to study human colonic cell proliferation.

    OpenAIRE

    Kubben, F J; Peeters-Haesevoets, A; Engels, L G; Baeten, C G; Schutte, B; Arends, J W; Stockbrügger, R W; Blijham, G H

    1994-01-01

    Immunohistochemistry of the S phase related proliferating cell nuclear antigen (PCNA) was studied as an alternative to ex-vivo bromodeoxyuridine (BrdU) immunohistochemistry for assessment of human colonic cell proliferation. From 16 subjects without colonic disease biopsy specimens were collected from five different sites along the colorectum and processed for BrdU and PCNA immunohistochemistry. The mean proliferation index of PCNA was significantly higher at 133% of the value obtained with B...

  5. miR-181a promotes G1/S transition and cell proliferation in pediatric acute myeloid leukemia by targeting ATM.

    Science.gov (United States)

    Liu, Xiaodan; Liao, Wang; Peng, Hongxia; Luo, Xuequn; Luo, Ziyan; Jiang, Hua; Xu, Ling

    2016-01-01

    Abnormal expression of miRNAs is intimately related to a variety of human cancers. The purpose of this study is to confirm the expression of miR-181a and elucidate its physiological function and mechanism in pediatric acute myeloid leukemia (AML). Pediatric AML patients and healthy controls were enrolled, and the expression of miR-181a and ataxia telangiectasia mutated (ATM) in tissues were examined using quantitative PCR. Moreover, cell proliferation and cell cycle were evaluated in several cell lines (HL60, NB4 and K562) by using flow cytometry after transfected with miR-181a mimics and inhibitors, or ATM siRNA and control siRNA. Finally, ATM as the potential target protein of miR-181a was examined. We found that miR-181a was significantly increased in pediatric AML, which showed an inverse association with ATM expression. Overexpressed miR-181a in cell lines significantly enhanced cell proliferation, as well as increased the ratio of S-phase cells by miR-181a mimics transfection in vitro. Luciferase activity of the reporter construct identified ATM as the direct molecular target of miR-181a. ATM siRNA transfection significantly enhanced cell proliferation and increased the ratio of S-phase cells in vitro. The results revealed novel mechanism through which miR-181a regulates G1/S transition and cell proliferation in pediatric AML by regulating the tumor suppressor ATM, providing insights into the molecular mechanism in pediatric AML.

  6. Overexpression of Hiwi Inhibits the Growth and Migration of Chronic Myeloid Leukemia Cells.

    Science.gov (United States)

    Wang, Yalin; Jiang, Yan; Ma, Ning; Sang, Bailu; Hu, Xiaolin; Cong, Xiaofeng; Liu, Ziling

    2015-09-01

    Chronic myeloid leukemia (CML) is a hematopoietic malignancy characterized by dysregulated growth and proliferation of hematopoietic stem/progenitor cells in bone marrow and excessive expansion of hematopoietic compartments in peripheral blood. Expression deletion of Hiwi, a human Piwi homolog, has been reported to be implicated in leukemogenesis. We here explored Hiwi's role in CML pathogenesis by determining how and whether its forced overexpression could affect CML cell growth and migration. The present results showed that lentivirus-mediated overexpression of Hiwi significantly suppressed cell proliferation and induced obvious apoptosis in K562 cells, a CML line cell line. Tumors in BALB/c nude mice generated by the K562 cells expressing Hiwi were much smaller than those formed by the control cells. Like in vitro, Hiwi upregulation induced cell apoptosis in the tumor tissues in vivo. Additionally, Hiwi elevation suppressed K562 cell migration and inhibited the activity and expression of matrix metalloproteinase-2 and -9. In summary, our study demonstrates that Hiwi overexpression inhibits CML cell growth and migration, providing insights into its role in CML pathogenesis.

  7. TWEAK induces liver progenitor cell proliferation

    Science.gov (United States)

    Jakubowski, Aniela; Ambrose, Christine; Parr, Michael; Lincecum, John M.; Wang, Monica Z.; Zheng, Timothy S.; Browning, Beth; Michaelson, Jennifer S.; Baestcher, Manfred; Wang, Bruce; Bissell, D. Montgomery; Burkly, Linda C.

    2005-01-01

    Progenitor (“oval”) cell expansion accompanies many forms of liver injury, including alcohol toxicity and submassive parenchymal necrosis as well as experimental injury models featuring blocked hepatocyte replication. Oval cells can potentially become either hepatocytes or biliary epithelial cells and may be critical to liver regeneration, particularly when hepatocyte replication is impaired. The regulation of oval cell proliferation is incompletely understood. Herein we present evidence that a TNF family member called TWEAK (TNF-like weak inducer of apoptosis) stimulates oval cell proliferation in mouse liver through its receptor Fn14. TWEAK has no effect on mature hepatocytes and thus appears to be selective for oval cells. Transgenic mice overexpressing TWEAK in hepatocytes exhibit periportal oval cell hyperplasia. A similar phenotype was obtained in adult wild-type mice, but not Fn14-null mice, by administering TWEAK-expressing adenovirus. Oval cell expansion induced by 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) was significantly reduced in Fn14-null mice as well as in adult wild-type mice with a blocking anti-TWEAK mAb. Importantly, TWEAK stimulated the proliferation of an oval cell culture model. Finally, we show increased Fn14 expression in chronic hepatitis C and other human liver diseases relative to its expression in normal liver, which suggests a role for the TWEAK/Fn14 pathway in human liver injury. We conclude that TWEAK has a selective mitogenic effect for liver oval cells that distinguishes it from other previously described growth factors. PMID:16110324

  8. CD34+ cells cultured in stem cell factor and interleukin-2 generate CD56+ cells with antiproliferative effects on tumor cell lines

    Directory of Open Access Journals (Sweden)

    Hensel Nancy

    2005-04-01

    Full Text Available Abstract In vitro stimulation of CD34+ cells with IL-2 induces NK cell differentiation. In order to define the stages of NK cell development, which influence their generation from CD34 cells, we cultured G-CSF mobilized peripheral blood CD34+ cells in the presence of stem cell factor and IL-2. After three weeks culture we found a diversity of CD56+ subsets which possessed granzyme A, but lacked the cytotoxic apparatus required for classical NK-like cytotoxicity. However, these CD56+ cells had the unusual property of inhibiting proliferation of K562 and P815 cell lines in a cell-contact dependent fashion.

  9. Arsenic and urinary bladder cell proliferation

    International Nuclear Information System (INIS)

    Luster, Michael I.; Simeonova, Petia P.

    2004-01-01

    Epidemiologic studies have demonstrated that a close association exists between the elevated levels of arsenic in drinking water and the incidence of certain cancers, including transitional cell carcinomas of the urinary bladder. We have employed in vitro and in vivo models to examine the effects of sodium arsenite on the urinary bladder epithelium. Mice exposed to 0.01% sodium arsenite in drinking water demonstrated hyperproliferation of the bladder uroepithelium within 4 weeks after initiating treatment. This occurred in the absence of amorphous precipitates and was accompanied by the accumulation of trivalent arsenite (iAs 3+ ), and to a lesser extent dimethylarsenic (DMA), arsenate (iAs 5+ ), and monomethylarsenic (MMA) in bladder tissue. In contrast to the bladder, urinary secretion was primarily in the form of DMA and MMA. Arsenic-induced cell proliferation in the bladder epithelium was correlated with activation of the MAP kinase pathway, leading to extracellular signal-regulated kinase (ERK) kinase activity, AP-1 activation, and expression of AP-1-associated genes involved in cell proliferation. Activation of the MAP kinase pathway involved both epidermal growth factor (EGF) receptor-dependent and -independent events, the latter involving Src activation. Studies summarized in this review suggest that arsenic accumulates in urinary bladder epithelium causing activation of specific signaling pathways that lead to chronic increased cell proliferation. This may play a non-epigenetic role in carcinogenesis by increasing the proliferation of initiated cells or increasing the mutational rate

  10. Nanomechanical measurement of adhesion and migration of leukemia cells with phorbol 12-myristate 13-acetate treatment.

    Science.gov (United States)

    Zhou, Zhuo Long; Ma, Jing; Tong, Ming-Hui; Chan, Barbara Pui; Wong, Alice Sze Tsai; Ngan, Alfonso Hing Wan

    The adhesion and traction behavior of leukemia cells in their microenvironment is directly linked to their migration, which is a prime issue affecting the release of cancer cells from the bone marrow and hence metastasis. In assessing the effectiveness of phorbol 12-myristate 13-acetate (PMA) treatment, the conventional batch-cell transwell-migration assay may not indicate the intrinsic effect of the treatment on migration, since the treatment may also affect other cellular behavior, such as proliferation or death. In this study, the pN-level adhesion and traction forces between single leukemia cells and their microenvironment were directly measured using optical tweezers and traction-force microscopy. The effects of PMA on K562 and THP1 leukemia cells were studied, and the results showed that PMA treatment significantly increased cell adhesion with extracellular matrix proteins, bone marrow stromal cells, and human fibroblasts. PMA treatment also significantly increased the traction of THP1 cells on bovine serum albumin proteins, although the effect on K562 cells was insignificant. Western blots showed an increased expression of E-cadherin and vimentin proteins after the leukemia cells were treated with PMA. The study suggests that PMA upregulates adhesion and thus suppresses the migration of both K562 and THP1 cells in their microenvironment. The ability of optical tweezers and traction-force microscopy to measure directly pN-level cell-protein or cell-cell contact was also demonstrated.

  11. Identification of coupling DNA motif pairs on long-range chromatin interactions in human K562 cells

    KAUST Repository

    Wong, Ka-Chun; Li, Yue; Peng, Chengbin

    2015-01-01

    Motivation: The protein-DNA interactions between transcription factors (TFs) and transcription factor binding sites (TFBSs, also known as DNA motifs) are critical activities in gene transcription. The identification of the DNA motifs is a vital task for downstream analysis. Unfortunately, the long-range coupling information between different DNA motifs is still lacking. To fill the void, as the first-of-its-kind study, we have identified the coupling DNA motif pairs on long-range chromatin interactions in human. Results: The coupling DNA motif pairs exhibit substantially higher DNase accessibility than the background sequences. Half of the DNA motifs involved are matched to the existing motif databases, although nearly all of them are enriched with at least one gene ontology term. Their motif instances are also found statistically enriched on the promoter and enhancer regions. Especially, we introduce a novel measurement called motif pairing multiplicity which is defined as the number of motifs that are paired with a given motif on chromatin interactions. Interestingly, we observe that motif pairing multiplicity is linked to several characteristics such as regulatory region type, motif sequence degeneracy, DNase accessibility and pairing genomic distance. Taken into account together, we believe the coupling DNA motif pairs identified in this study can shed lights on the gene transcription mechanism under long-range chromatin interactions. © The Author 2015. Published by Oxford University Press.

  12. VDAC2 and aldolase A identified as membrane proteins of K562 cells with increased expression under iron deprivation

    Czech Academy of Sciences Publication Activity Database

    Vališ, Karel; Neubauerová, J.; Man, Petr; Pompach, Petr; Vohradský, Jiří; Kovář, J.

    2008-01-01

    Roč. 311, 1-2 (2008), 225-231 ISSN 0300-8177 Institutional research plan: CEZ:AV0Z50520701; CEZ:AV0Z50200510 Keywords : Iron deprivation * aldolase A * VDAC2 Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.764, year: 2008

  13. Identification of coupling DNA motif pairs on long-range chromatin interactions in human K562 cells

    KAUST Repository

    Wong, Ka-Chun

    2015-09-27

    Motivation: The protein-DNA interactions between transcription factors (TFs) and transcription factor binding sites (TFBSs, also known as DNA motifs) are critical activities in gene transcription. The identification of the DNA motifs is a vital task for downstream analysis. Unfortunately, the long-range coupling information between different DNA motifs is still lacking. To fill the void, as the first-of-its-kind study, we have identified the coupling DNA motif pairs on long-range chromatin interactions in human. Results: The coupling DNA motif pairs exhibit substantially higher DNase accessibility than the background sequences. Half of the DNA motifs involved are matched to the existing motif databases, although nearly all of them are enriched with at least one gene ontology term. Their motif instances are also found statistically enriched on the promoter and enhancer regions. Especially, we introduce a novel measurement called motif pairing multiplicity which is defined as the number of motifs that are paired with a given motif on chromatin interactions. Interestingly, we observe that motif pairing multiplicity is linked to several characteristics such as regulatory region type, motif sequence degeneracy, DNase accessibility and pairing genomic distance. Taken into account together, we believe the coupling DNA motif pairs identified in this study can shed lights on the gene transcription mechanism under long-range chromatin interactions. © The Author 2015. Published by Oxford University Press.

  14. NSAIDs and Cell Proliferation in Colorectal Cancer

    Directory of Open Access Journals (Sweden)

    Raj Ettarh

    2010-06-01

    Full Text Available Colon cancer is common worldwide and accounts for significant morbidity and mortality in patients. Fortunately, epidemiological studies have demonstrated that continuous therapy with NSAIDs offers real promise of chemoprevention and adjunct therapy for colon cancer patients. Tumour growth is the result of complex regulation that determines the balance between cell proliferation and cell death. How NSAIDs affect this balance is important for understanding and improving treatment strategies and drug effectiveness. NSAIDs inhibit proliferation and impair the growth of colon cancer cell lines when tested in culture in vitro and many NSAIDs also prevent tumorigenesis and reduce tumour growth in animal models and in patients, but the relationship to inhibition of tumour cell proliferation is less convincing, principally due to gaps in the available data. High concentrations of NSAIDs are required in vitro to achieve cancer cell inhibition and growth retardation at varying time-points following treatment. However, the results from studies with colon cancer cell xenografts are promising and, together with better comparative data on anti-proliferative NSAID concentrations and doses (for in vitro and in vivo administration, could provide more information to improve our understanding of the relationships between these agents, dose and dosing regimen, and cellular environment.

  15. Cell proliferation and ageing in mouse colon

    International Nuclear Information System (INIS)

    Hamilton, E.; Franks, L.M.

    1980-01-01

    Cell kinetic parameters in the descending colon of unirradiated mice, 3-30-months-old were compared with those in mice irradiated repeatedly from the age of 6 or 24 months. The latter animals were given 1250 rad local X-irradiation to the colon every 6 weeks. Dose-survival curves showed the colon crypts of 6 and 24-months-old mice were similarly radiosensitive. In unirradiated mice the number of crypts per colon section decreased significantly at 30 months, but no significant age-related changes were seen in crypt size or labelling index (LI). Cell proliferation returned to control levels within 6 weeks of each X-ray dose and remained at this level for 20 weeks after the final dose. Later, cell proliferation in the irradiated colon fell significantly below control. A total of 6 or 7 doses each of 1250 rad produced only 1 colon carcinoma amongst 50 mice kept until they died. (author)

  16. Disrupting BCR-ABL in combination with secondary leukemia-specific pathways in CML cells leads to enhanced apoptosis and decreased proliferation.

    Science.gov (United States)

    Woessner, David W; Lim, Carol S

    2013-01-07

    Chronic myeloid leukemia (CML) is a myeloproliferative disorder caused by expression of the fusion gene BCR-ABL following a chromosomal translocation in the hematopoietic stem cell. Therapeutic management of CML uses tyrosine kinase inhibitors (TKIs), which block ABL-signaling and effectively kill peripheral cells with BCR-ABL. However, TKIs are not curative, and chronic use is required in order to treat CML. The primary failure for TKIs is through the development of a resistant population due to mutations in the TKI binding regions. This led us to develop the mutant coiled-coil, CC(mut2), an alternative method for BCR-ABL signaling inhibition by targeting the N-terminal oligomerization domain of BCR, necessary for ABL activation. In this article, we explore additional pathways that are important for leukemic stem cell survival in K562 cells. Using a candidate-based approach, we test the combination of CC(mut2) and inhibitors of unique secondary pathways in leukemic cells. Transformative potential was reduced following silencing of the leukemic stem cell factor Alox5 by RNA interference. Furthermore, blockade of the oncogenic protein MUC-1 by the novel peptide GO-201 yielded reductions in proliferation and increased cell death. Finally, we found that inhibiting macroautophagy using chloroquine in addition to blocking BCR-ABL signaling with the CC(mut2) was most effective in limiting cell survival and proliferation. This study has elucidated possible combination therapies for CML using novel blockade of BCR-ABL and secondary leukemia-specific pathways.

  17. Suppression of bcr-abl synthesis by siRNAs or tyrosine kinase activity by Glivec alters different oncogenes, apoptotic/antiapoptotic genes and cell proliferation factors (microarray study).

    Science.gov (United States)

    Zhelev, Zhivko; Bakalova, Rumiana; Ohba, Hideki; Ewis, Ashraf; Ishikawa, Mitsuru; Shinohara, Yasuo; Baba, Yoshinobu

    2004-07-16

    Short 21-mer double-stranded/small-interfering RNAs (ds/siRNAs) were designed to target bcr-abl mRNA in chronic myelogenous leukemia. The ds/siRNAs were transfected into bcr-abl-positive K-562 (derived from blast crisis chronic myelogenous leukemia), using lipofectamine. Penetrating of ds/siRNAs into the cells was detected by fluorescent confocal microscopy, using fluorescein-labeled ds/siRNAs. The cells were treated with mix of three siRNA sequences (3 x 60 nM) during 6 days with three repetitive transfections. The siRNA-treatment was accompanied with significant reduction of bcr-abl mRNA, p210, protein tyrosine kinase activity and cell proliferation index. Treatment of cells with Glivec (during 8 days with four repetitive doses, 180 nM single dose) resulted in analogous reduction of cell proliferation activity, stronger suppression of protein tyrosine kinase activity, and very low reduction of p210. siRNA-mix and Glivec did not affect significantly the viability of normal lymphocytes. Microarray analysis of siRNA- and Glivec-treated K-562 cells demonstrated that both pathways of bcr-abl suppression were accompanied with overexpression and suppression of many different oncogenes, apoptotic/antiapoptotic and cell proliferation factors. The following genes of interest were found to decrease in relatively equal degree in both siRNA- and Glivec-treated cells: Bcd orf1 and orf2 proto-oncogene, chromatin-specific transcription elongation factor FACT 140-kDa subunit mRNA, gene encoding splicing factor SF1, and mRNA for Tec protein tyrosine kinase. siRNA-mix and Glivec provoked overexpression of the following common genes: c-jun proto-oncogene, protein kinase C-alpha, pvt-1 oncogene homologue (myc activator), interleukin-6, 1-8D gene from interferon-inducible gene family, tumor necrosis factor receptor superfamily (10b), and STAT-induced STAT inhibitor.

  18. Polyamines and post-irradiation cell proliferation

    International Nuclear Information System (INIS)

    Rosiek, O.; Wronowski, T.; Lerozak, K.; Kopec, M.

    1978-01-01

    The results of three sets of experiments will be presented. Firstly polyamines and DNA content was determined in bone marrow, mesenteric lymph nodes, spleen, liver and kidney of rabbits at the 1, 5, 10 and 20th day after exposure to 600 R of X-irradiation. Polyamine concentration in bone marrow, spleen and lymph nodes was found to be markedly increased during the period of postirradiation recovery. Secondly, effect of 10 -5 M methyl glyoxalbis, guanylhydrazone (MGBG), an inhibitor of spermidine and spermine synthesis, on multiplication of X-irradiated cultures of murine lymphoblaste L5178Y-S was assessed. MGBG-induced inhibition of cell proliferation could be prevented by concurrent administration of 10 -4 M spermidine. Thirdly the influence of putrescine on bone marrow cellularity and 3 H-thymidine incorporation into bone marrow cells was investigated in X-irradiated mice. The results obtained indicate close relation of polyamines to cell proliferation processes after irradiation. (orig./AJ) [de

  19. Oxidative stress induced pulmonary endothelial cell proliferation is ...

    African Journals Online (AJOL)

    Cellular hyper-proliferation, endothelial dysfunction and oxidative stress are hallmarks of the pathobiology of pulmonary hypertension. Indeed, pulmonary endothelial cells proliferation is susceptible to redox state modulation. Some studies suggest that superoxide stimulates endothelial cell proliferation while others have ...

  20. Cell proliferation and ageing in mouse colon

    International Nuclear Information System (INIS)

    Hamilton, E.

    1978-01-01

    The descending colon of 4 month and 2 year old mice was exposed to 1250 rad X-rays. This killed most of the epithelial cells. The surviving cells formed new crypts and surface epithelium in animals of both ages. Not all of the crypts were replaced. The irradiated area contained not more than 80% of the control number of crypts per section for at least 6 weeks after irradiation. In the young mice new crypts were much larger and the labelling index (LI) was much higher than in unirradiated animals during the first week after irradiation. In the old mice the overshoot in LI and crypt size began later and continued longer than in young animals. This may be because the control of cell proliferation was much less precise in old than in young mice. The irradiation was repeated, in attempt to age prematurely the epithelial cells by increasing the number of divisions they underwent. The overshoot in LI and cells per crypt was smaller after a second dose than after the first in both young and old mice. There was almost no overshoot after a third dose was given to young mice. Increasing the number of divisions undergone by the surviving epithelial cells did not change the timing of repopulation in young mice compared to that found in old mice. Little evidence was found for the presence of a limited proliferative lifespan in colon epithelial cells. (author)

  1. Cell proliferation alterations in Chlorella cells under stress conditions

    International Nuclear Information System (INIS)

    Rioboo, Carmen; O'Connor, Jose Enrique; Prado, Raquel; Herrero, Concepcion; Cid, Angeles

    2009-01-01

    Very little is known about growth and proliferation in relation to the cell cycle regulation of algae. The lack of knowledge is even greater when referring to the potential toxic effects of pollutants on microalgal cell division. To assess the effect of terbutryn, a triazine herbicide, on the proliferation of the freshwater microalga Chlorella vulgaris three flow cytometric approaches were used: (1) in vivo cell division using 5-,6-carboxyfluorescein diacetate succinimidyl ester (CFSE) staining was measured, (2) the growth kinetics were determined by cytometric cell counting and (3) cell viability was evaluated with the membrane-impermeable double-stranded nucleic acid stain propidium iodide (PI). The results obtained in the growth kinetics study using CFSE to identify the microalgal cell progeny were consistent with those determined by cytometric cell counting. In all C. vulgaris cultures, each mother cell had undergone only one round of division through the 96 h of assay and the cell division occurred during the dark period. Cell division of the cultures exposed to the herbicide was asynchronous. Terbutryn altered the normal number of daughter cells (4 autospores) obtained from each mother cell. The number was only two in the cultures treated with 250 nM. The duration of the lag phase after the exposure to terbutryn could be dependent on the existence of a critical cell size to activate cytoplasmic division. Cell size, complexity and fluorescence of chlorophyll a of the microalgal cells presented a marked light/dark (day/night) cycle, except in the non-dividing 500 nM cultures, where terbutryn arrested cell division at the beginning of the cycle. Viability results showed that terbutryn has an algastatic effect in C. vulgaris cells at this concentration. The rapid and precise determination of cell proliferation by CFSE staining has allowed us to develop a model for assessing both the cell cycle of C. vulgaris and the in vivo effects of pollutants on growth and

  2. Cell proliferation alterations in Chlorella cells under stress conditions

    Energy Technology Data Exchange (ETDEWEB)

    Rioboo, Carmen [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n, 15008 A Coruna (Spain); O' Connor, Jose Enrique [Laboratorio de Citomica, Unidad Mixta de Investigacion CIPF-UVEG, Centro de Investigacion Principe Felipe, Avda. Autopista del Saler, 16, 46013 Valencia (Spain); Prado, Raquel; Herrero, Concepcion [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n, 15008 A Coruna (Spain); Cid, Angeles, E-mail: cid@udc.es [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n, 15008 A Coruna (Spain)

    2009-09-14

    Very little is known about growth and proliferation in relation to the cell cycle regulation of algae. The lack of knowledge is even greater when referring to the potential toxic effects of pollutants on microalgal cell division. To assess the effect of terbutryn, a triazine herbicide, on the proliferation of the freshwater microalga Chlorella vulgaris three flow cytometric approaches were used: (1) in vivo cell division using 5-,6-carboxyfluorescein diacetate succinimidyl ester (CFSE) staining was measured, (2) the growth kinetics were determined by cytometric cell counting and (3) cell viability was evaluated with the membrane-impermeable double-stranded nucleic acid stain propidium iodide (PI). The results obtained in the growth kinetics study using CFSE to identify the microalgal cell progeny were consistent with those determined by cytometric cell counting. In all C. vulgaris cultures, each mother cell had undergone only one round of division through the 96 h of assay and the cell division occurred during the dark period. Cell division of the cultures exposed to the herbicide was asynchronous. Terbutryn altered the normal number of daughter cells (4 autospores) obtained from each mother cell. The number was only two in the cultures treated with 250 nM. The duration of the lag phase after the exposure to terbutryn could be dependent on the existence of a critical cell size to activate cytoplasmic division. Cell size, complexity and fluorescence of chlorophyll a of the microalgal cells presented a marked light/dark (day/night) cycle, except in the non-dividing 500 nM cultures, where terbutryn arrested cell division at the beginning of the cycle. Viability results showed that terbutryn has an algastatic effect in C. vulgaris cells at this concentration. The rapid and precise determination of cell proliferation by CFSE staining has allowed us to develop a model for assessing both the cell cycle of C. vulgaris and the in vivo effects of pollutants on growth and

  3. A secreted factor represses cell proliferation in Dictyostelium

    OpenAIRE

    Brock, Debra A.; Gomer, Richard H.

    2005-01-01

    Many cells appear to secrete factors called chalones that limit their proliferation, but in most cases the factors have not been identified. We found that growing Dictyostelium cells secrete a 60 kDa protein called AprA for autocrine proliferation repressor. AprA has similarity to putative bacterial proteins of unknown function. Compared with wild-type cells, aprA-null cells proliferate faster, while AprA overexpressing cells proliferate slower. Growing wild-type cells secrete a factor that i...

  4. Xylitol induces cell death in lung cancer A549 cells by autophagy.

    Science.gov (United States)

    Park, Eunjoo; Park, Mi Hee; Na, Hee Sam; Chung, Jin

    2015-05-01

    Xylitol is a widely used anti-caries agent that has anti-inflammatory effects. We have evaluated the potential of xylitol in cancer treatment. It's effects on cell proliferation and cytotoxicity were measured by MTT assay and LDH assay. Cell morphology and autophagy were examined by immunostaining and immunoblotting. Xylitol inhibited cell proliferation in a dose-dependent manner in these cancer cells: A549, Caki, NCI-H23, HCT-15, HL-60, K562, and SK MEL-2. The IC50 of xylitol in human gingival fibroblast cells was higher than in cancer cells, indicating that it is more specific for cancer cells. Moreover, xylitol induced autophagy in A549 cells that was inhibited by 3-methyladenine, an autophagy inhibitor. These results indicate that xylitol has potential in therapy against lung cancer by inhibiting cell proliferation and inducing autophagy of A549 cells.

  5. Satellite cell proliferation in adult skeletal muscle

    Science.gov (United States)

    Booth, Frank W. (Inventor); Thomason, Donald B. (Inventor); Morrison, Paul R. (Inventor); Stancel, George M. (Inventor)

    1995-01-01

    Novel methods of retroviral-mediated gene transfer for the in vivo corporation and stable expression of eukaryotic or prokaryotic foreign genes in tissues of living animals is described. More specifically, methods of incorporating foreign genes into mitotically active cells are disclosed. The constitutive and stable expression of E. coli .beta.-galactosidase gene under the promoter control of the Moloney murine leukemia virus long terminal repeat is employed as a particularly preferred embodiment, by way of example, establishes the model upon which the incorporation of a foreign gene into a mitotically-active living eukaryotic tissue is based. Use of the described methods in therapeutic treatments for genetic diseases, such as those muscular degenerative diseases, is also presented. In muscle tissue, the described processes result in genetically-altered satellite cells which proliferate daughter myoblasts which preferentially fuse to form a single undamaged muscle fiber replacing damaged muscle tissue in a treated animal. The retroviral vector, by way of example, includes a dystrophin gene construct for use in treating muscular dystrophy. The present invention also comprises an experimental model utilizable in the study of the physiological regulation of skeletal muscle gene expression in intact animals.

  6. Dual effect of LPS on murine myeloid leukemia cells: Pro-proliferation and anti-proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Lingling [Department of Pediatrics, Jingjiang People' s Hospital, Yangzhou University, Jingjiang 214500 (China); Noncoding RNA Center, Yangzhou University, Yangzhou 225001 (China); Zhao, Yingmin [Department of Pediatrics, Jingjiang People' s Hospital, Yangzhou University, Jingjiang 214500 (China); Gu, Xin; Wang, Jijun; Pang, Lei; Zhang, Yanqing; Li, Yaoyao; Jia, Xiaoqin; Wang, Xin [Noncoding RNA Center, Yangzhou University, Yangzhou 225001 (China); Gu, Jian [Department of Hematology, Yangzhou University School of Clinical Medicine, Yangzhou 225001 (China); Yu, Duonan, E-mail: duonan@yahoo.com [Department of Pediatrics, Jingjiang People' s Hospital, Yangzhou University, Jingjiang 214500 (China); Noncoding RNA Center, Yangzhou University, Yangzhou 225001 (China); Jiangsu Key Laboratory of Integrated Traditional Chinese and Western Medicine for Prevention and Treatment of Senile Disease, Yangzhou 225001 (China); Institute of Comparative Medicine, Yangzhou University, Yangzhou 225001 (China); Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Disease and Zoonosis, Yangzhou 225001 (China)

    2016-06-10

    Modification of the bone marrow microenvironment is considered as a promising strategy to control leukemic cell proliferation, diseases progression and relapse after treatment. However, due to the diversity and complexity of the cellular and molecular compartments in the leukemic microenvironment, it is extremely difficult to dissect the role of each individual molecule or cell type in vivo. Here we established an in vitro system to dissect the role of lipopolysaccharide (LPS), stromal cells and endothelial cells in the growth of mouse myeloid tumor cells and B-lymphoma cells. We found that either LPS or bone marrow stromal cells as a feeder layer in culture is required for the proliferation of myeloid tumor cells. Surprisingly, the growth of myeloid leukemic cells on stromal cells is strongly inhibited when coupled with LPS in culture. This opposing effect of LPS, a complete switch from pro-proliferation to antitumor growth is due, at least in part, to the rapidly increased production of interleukin 12, Fas ligand and tissue inhibitor of metalloproteinases-2 from stromal cells stimulated by LPS. These results demonstrate that LPS can either facilitate or attenuate tumor cell proliferation, thus changing the disease course of myeloid leukemias through its direct effect or modulation of the tumor microenvironment. - Highlights: • LPS alone in culture is required for the proliferation of murine myeloid tumor cells. • Bone marrow stromal cells as a feeder layer is also required for the proliferation of myeloid tumor cells. • However, the growth of myeloid tumor cells is inhibited when LPS and stromal cells are both available in culture. • Thus LPS can either facilitate or attenuate tumor growth through its direct effect or modulation of tumor microenvironment.

  7. Dual effect of LPS on murine myeloid leukemia cells: Pro-proliferation and anti-proliferation

    International Nuclear Information System (INIS)

    Yu, Lingling; Zhao, Yingmin; Gu, Xin; Wang, Jijun; Pang, Lei; Zhang, Yanqing; Li, Yaoyao; Jia, Xiaoqin; Wang, Xin; Gu, Jian; Yu, Duonan

    2016-01-01

    Modification of the bone marrow microenvironment is considered as a promising strategy to control leukemic cell proliferation, diseases progression and relapse after treatment. However, due to the diversity and complexity of the cellular and molecular compartments in the leukemic microenvironment, it is extremely difficult to dissect the role of each individual molecule or cell type in vivo. Here we established an in vitro system to dissect the role of lipopolysaccharide (LPS), stromal cells and endothelial cells in the growth of mouse myeloid tumor cells and B-lymphoma cells. We found that either LPS or bone marrow stromal cells as a feeder layer in culture is required for the proliferation of myeloid tumor cells. Surprisingly, the growth of myeloid leukemic cells on stromal cells is strongly inhibited when coupled with LPS in culture. This opposing effect of LPS, a complete switch from pro-proliferation to antitumor growth is due, at least in part, to the rapidly increased production of interleukin 12, Fas ligand and tissue inhibitor of metalloproteinases-2 from stromal cells stimulated by LPS. These results demonstrate that LPS can either facilitate or attenuate tumor cell proliferation, thus changing the disease course of myeloid leukemias through its direct effect or modulation of the tumor microenvironment. - Highlights: • LPS alone in culture is required for the proliferation of murine myeloid tumor cells. • Bone marrow stromal cells as a feeder layer is also required for the proliferation of myeloid tumor cells. • However, the growth of myeloid tumor cells is inhibited when LPS and stromal cells are both available in culture. • Thus LPS can either facilitate or attenuate tumor growth through its direct effect or modulation of tumor microenvironment.

  8. Inhibition of fatty acid metabolism reduces human myeloma cells proliferation.

    Directory of Open Access Journals (Sweden)

    José Manuel Tirado-Vélez

    Full Text Available Multiple myeloma is a haematological malignancy characterized by the clonal proliferation of plasma cells. It has been proposed that targeting cancer cell metabolism would provide a new selective anticancer therapeutic strategy. In this work, we tested the hypothesis that inhibition of β-oxidation and de novo fatty acid synthesis would reduce cell proliferation in human myeloma cells. We evaluated the effect of etomoxir and orlistat on fatty acid metabolism, glucose metabolism, cell cycle distribution, proliferation, cell death and expression of G1/S phase regulatory proteins in myeloma cells. Etomoxir and orlistat inhibited β-oxidation and de novo fatty acid synthesis respectively in myeloma cells, without altering significantly glucose metabolism. These effects were associated with reduced cell viability and cell cycle arrest in G0/G1. Specifically, etomoxir and orlistat reduced by 40-70% myeloma cells proliferation. The combination of etomoxir and orlistat resulted in an additive inhibitory effect on cell proliferation. Orlistat induced apoptosis and sensitized RPMI-8226 cells to apoptosis induction by bortezomib, whereas apoptosis was not altered by etomoxir. Finally, the inhibitory effect of both drugs on cell proliferation was associated with reduced p21 protein levels and phosphorylation levels of retinoblastoma protein. In conclusion, inhibition of fatty acid metabolism represents a potential therapeutic approach to treat human multiple myeloma.

  9. In vitro proliferation of adult human beta-cells.

    Directory of Open Access Journals (Sweden)

    Sabine Rutti

    Full Text Available A decrease in functional beta-cell mass is a key feature of type 2 diabetes. Glucagon-like peptide 1 (GLP-1 analogues induce proliferation of rodent beta-cells. However, the proliferative capacity of human beta-cells and its modulation by GLP-1 analogues remain to be fully investigated. We therefore sought to quantify adult human beta-cell proliferation in vitro and whether this is affected by the GLP-1 analogue liraglutide.Human islets from 7 adult cadaveric organ donors were dispersed into single cells. Beta-cells were purified by FACS. Non-sorted cells and the beta-cell enriched ("beta-cells" population were plated on extracellular matrix from rat (804G and human bladder carcinoma cells (HTB9 or bovine corneal endothelial ECM (BCEC. Cells were maintained in culture+/-liraglutide for 4 days in the presence of BrdU.Rare human beta-cell proliferation could be observed either in the purified beta-cell population (0.051±0.020%; 22 beta-cells proliferating out of 84'283 beta-cells counted or in the non-sorted cell population (0.055±0.011%; 104 proliferating beta-cells out of 232'826 beta-cells counted, independently of the matrix or the culture conditions. Liraglutide increased human beta-cell proliferation on BCEC in the non-sorted cell population (0.082±0.034% proliferating beta-cells vs. 0.017±0.008% in control, p<0.05.These results indicate that adult human beta-cell proliferation can occur in vitro but remains an extremely rare event with these donors and particular culture conditions. Liraglutide increases beta-cell proliferation only in the non-sorted cell population and only on BCEC. However, it cannot be excluded that human beta-cells may proliferate to a greater extent in situ in response to natural stimuli.

  10. A secreted factor represses cell proliferation in Dictyostelium.

    Science.gov (United States)

    Brock, Debra A; Gomer, Richard H

    2005-10-01

    Many cells appear to secrete factors called chalones that limit their proliferation, but in most cases the factors have not been identified. We found that growing Dictyostelium cells secrete a 60 kDa protein called AprA for autocrine proliferation repressor. AprA has similarity to putative bacterial proteins of unknown function. Compared with wild-type cells, aprA-null cells proliferate faster, while AprA overexpressing cells proliferate slower. Growing wild-type cells secrete a factor that inhibits the proliferation of wild-type and aprA- cells; this activity is not secreted by aprA- cells. AprA purified by immunoprecipitation also slows the proliferation of wild-type and aprA- cells. Compared with wild type, there is a higher percentage of multinucleate cells in the aprA- population, and when starved, aprA- cells form abnormal structures that contain fewer spores. AprA may thus decrease the number of multinucleate cells and increase spore production. Together, the data suggest that AprA functions as part of a Dictyostelium chalone.

  11. Human tumor cell proliferation evaluated using manganese-enhanced MRI.

    Directory of Open Access Journals (Sweden)

    Rod D Braun

    Full Text Available Tumor cell proliferation can depend on calcium entry across the cell membrane. As a first step toward the development of a non-invasive test of the extent of tumor cell proliferation in vivo, we tested the hypothesis that tumor cell uptake of a calcium surrogate, Mn(2+ [measured with manganese-enhanced MRI (MEMRI], is linked to proliferation rate in vitro.Proliferation rates were determined in vitro in three different human tumor cell lines: C918 and OCM-1 human uveal melanomas and PC-3 prostate carcinoma. Cells growing at different average proliferation rates were exposed to 1 mM MnCl(2 for one hour and then thoroughly washed. MEMRI R(1 values (longitudinal relaxation rates, which have a positive linear relationship with Mn(2+ concentration, were then determined from cell pellets. Cell cycle distributions were determined using propidium iodide staining and flow cytometry. All three lines showed Mn(2+-induced increases in R(1 compared to cells not exposed to Mn(2+. C918 and PC-3 cells each showed a significant, positive correlation between MEMRI R(1 values and proliferation rate (p≤0.005, while OCM-1 cells showed no significant correlation. Preliminary, general modeling of these positive relationships suggested that pellet R(1 for the PC-3 cells, but not for the C918 cells, could be adequately described by simply accounting for changes in the distribution of the cell cycle-dependent subpopulations in the pellet.These data clearly demonstrate the tumor-cell dependent nature of the relationship between proliferation and calcium influx, and underscore the usefulness of MEMRI as a non-invasive method for investigating this link. MEMRI is applicable to study tumors in vivo, and the present results raise the possibility of evaluating proliferation parameters of some tumor types in vivo using MEMRI.

  12. Blockade of Y177 and Nuclear Translocation of Bcr-Abl Inhibits Proliferation and Promotes Apoptosis in Chronic Myeloid Leukemia Cells.

    Science.gov (United States)

    Li, Qianyin; Huang, Zhenglan; Gao, Miao; Cao, Weixi; Xiao, Qin; Luo, Hongwei; Feng, Wenli

    2017-03-02

    The gradual emerging of resistance to imatinib urgently calls for the development of new therapy for chronic myeloid leukemia (CML). The fusion protein Bcr-Abl, which promotes the malignant transformation of CML cells, is mainly located in the cytoplasm, while the c-Abl protein which is expressed in the nucleus can induce apoptosis. Based on the hetero-dimerization of FKBP (the 12-kDa FK506- and rapamycin-binding protein) and FRB (the FKBP-rapamycin binding domain of the protein kinase, mTOR) mediated by AP21967, we constructed a nuclear transport system to induce cytoplasmic Bcr-Abl into nuclear. In this study, we reported the construction of the nuclear transport system, and we demonstrated that FN3R (three nuclear localization signals were fused to FRBT2098L with a FLAG tag), HF2S (two FKBP domains were in tandem and fused to the SH2 domain of Grb2 with an HA tag) and Bcr-Abl form a complexus upon AP21967. Bcr-Abl was imported into the nucleus successfully by the nuclear transport system. The nuclear transport system inhibited CML cell proliferation through mitogen-activated protein kinase (MAPK) and signal transducer and activator of transcription 5 (STAT5) pathways mainly by HF2S. It was proven that nuclear located Bcr-Abl induced CML cell (including imatinib-resistant K562G01 cells) apoptosis by activation of p73 and its downstream molecules. In summary, our study provides a new targeted therapy for the CML patients even with Tyrosine Kinase Inhibitor (TKI)-resistance.

  13. Blockade of Y177 and Nuclear Translocation of Bcr-Abl Inhibits Proliferation and Promotes Apoptosis in Chronic Myeloid Leukemia Cells

    Directory of Open Access Journals (Sweden)

    Qianyin Li

    2017-03-01

    Full Text Available The gradual emerging of resistance to imatinib urgently calls for the development of new therapy for chronic myeloid leukemia (CML. The fusion protein Bcr-Abl, which promotes the malignant transformation of CML cells, is mainly located in the cytoplasm, while the c-Abl protein which is expressed in the nucleus can induce apoptosis. Based on the hetero-dimerization of FKBP (the 12-kDa FK506- and rapamycin-binding protein and FRB (the FKBP-rapamycin binding domain of the protein kinase, mTOR mediated by AP21967, we constructed a nuclear transport system to induce cytoplasmic Bcr-Abl into nuclear. In this study, we reported the construction of the nuclear transport system, and we demonstrated that FN3R (three nuclear localization signals were fused to FRBT2098L with a FLAG tag, HF2S (two FKBP domains were in tandem and fused to the SH2 domain of Grb2 with an HA tag and Bcr-Abl form a complexus upon AP21967. Bcr-Abl was imported into the nucleus successfully by the nuclear transport system. The nuclear transport system inhibited CML cell proliferation through mitogen-activated protein kinase (MAPK and signal transducer and activator of transcription 5 (STAT5 pathways mainly by HF2S. It was proven that nuclear located Bcr-Abl induced CML cell (including imatinib-resistant K562G01 cells apoptosis by activation of p73 and its downstream molecules. In summary, our study provides a new targeted therapy for the CML patients even with Tyrosine Kinase Inhibitor (TKI-resistance.

  14. Resveratrol-induced transcriptional up-regulation of ASMase (SMPD1) of human leukemia and cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Mizutani, Naoki [Department of Pathophysiological Laboratory Science, Nagoya University Graduate School of Medicine, Nagoya (Japan); College of Life and Health Sciences, Chubu University, Kasugai (Japan); Omori, Yukari [Department of Pathophysiological Laboratory Science, Nagoya University Graduate School of Medicine, Nagoya (Japan); Kawamoto, Yoshiyuki; Sobue, Sayaka; Ichihara, Masatoshi [College of Life and Health Sciences, Chubu University, Kasugai (Japan); Suzuki, Motoshi [Division of Molecular Carcinogenesis, Nagoya University Graduate School of Medicine, Nagoya (Japan); Kyogashima, Mamoru [Department of Microbiology and Molecular Biology, Nihon Pharmaceutical University, Saitama (Japan); Nakamura, Mitsuhiro [Department of Drug Information, Gifu Pharmaceutical University, Gifu (Japan); Tamiya-Koizumi, Keiko [College of Life and Health Sciences, Chubu University, Kasugai (Japan); Nozawa, Yoshinori [Tokai Gakuin University, Kakamigahara (Japan); Murate, Takashi, E-mail: murate@isc.chubu.ac.jp [College of Life and Health Sciences, Chubu University, Kasugai (Japan)

    2016-02-19

    Resveratrol (RSV) is a plant-derived phytoalexin present in plants, whose pleiotropic effects for health benefits have been previously reported. Its anti-cancer activity is among the current topics for novel cancer treatment. Here, effects of RSV on cell proliferation and the sphingolipid metabolism of K562, a human leukemia cell line, were analyzed. Some experiments were also performed in HCT116, a human colon cancer cell line. RSV inhibited cell proliferation of both cell lines. Increased cellular ceramide and decreased sphingomyelin and S1P by RSV were observed in RSV-treated K562 cells. Further analysis revealed that acid sphingomyelinase mRNA and enzyme activity levels were increased by RSV. Desipramine, a functional ASMase inhibitor, prevented RSV-induced ceramide increase. RSV increased ATF3, EGR1, EGR3 proteins and phosphorylated c-Jun and FOXO3. However, co-transfection using these transcription factor expression vectors and ASMase promoter reporter vector revealed positive effects of EGR1 and EGR3 but not others. Electrophoresis mobility shift assay (EMSA) and Chromatin immunoprecipitation (ChIP) assay demonstrated the direct binding of EGR1/3 transcription factors with ASMase 5′-promoter. These results indicate that increased EGR1/3 and ASMase expression play an important role in cellular ceramide increase by RSV treatment. - Highlights: • Resveratrol inhibited cell proliferation of K562 and HCT116 cells. • Resveratrol increased cellular ceramide and decreased sphingomyelin and S1P. • ASMase mRNA and activity were increased with resveratrol. • ASMase inhibition suppressed RSV-induced ceramide accumulation. • Increased ASMase transcription was at least partially due to EGR family proteins.

  15. Resveratrol-induced transcriptional up-regulation of ASMase (SMPD1) of human leukemia and cancer cells

    International Nuclear Information System (INIS)

    Mizutani, Naoki; Omori, Yukari; Kawamoto, Yoshiyuki; Sobue, Sayaka; Ichihara, Masatoshi; Suzuki, Motoshi; Kyogashima, Mamoru; Nakamura, Mitsuhiro; Tamiya-Koizumi, Keiko; Nozawa, Yoshinori; Murate, Takashi

    2016-01-01

    Resveratrol (RSV) is a plant-derived phytoalexin present in plants, whose pleiotropic effects for health benefits have been previously reported. Its anti-cancer activity is among the current topics for novel cancer treatment. Here, effects of RSV on cell proliferation and the sphingolipid metabolism of K562, a human leukemia cell line, were analyzed. Some experiments were also performed in HCT116, a human colon cancer cell line. RSV inhibited cell proliferation of both cell lines. Increased cellular ceramide and decreased sphingomyelin and S1P by RSV were observed in RSV-treated K562 cells. Further analysis revealed that acid sphingomyelinase mRNA and enzyme activity levels were increased by RSV. Desipramine, a functional ASMase inhibitor, prevented RSV-induced ceramide increase. RSV increased ATF3, EGR1, EGR3 proteins and phosphorylated c-Jun and FOXO3. However, co-transfection using these transcription factor expression vectors and ASMase promoter reporter vector revealed positive effects of EGR1 and EGR3 but not others. Electrophoresis mobility shift assay (EMSA) and Chromatin immunoprecipitation (ChIP) assay demonstrated the direct binding of EGR1/3 transcription factors with ASMase 5′-promoter. These results indicate that increased EGR1/3 and ASMase expression play an important role in cellular ceramide increase by RSV treatment. - Highlights: • Resveratrol inhibited cell proliferation of K562 and HCT116 cells. • Resveratrol increased cellular ceramide and decreased sphingomyelin and S1P. • ASMase mRNA and activity were increased with resveratrol. • ASMase inhibition suppressed RSV-induced ceramide accumulation. • Increased ASMase transcription was at least partially due to EGR family proteins.

  16. Tumor cell proliferation kinetics and tumor growth rate

    Energy Technology Data Exchange (ETDEWEB)

    Tubiana, M

    1989-01-01

    The present knowledge on the growth rate and the proliferation kinetics of human tumor is based on the measurement of the tumor doubling times (DT) in several hundred patients and on the determination of the proportion of proliferating cells with radioactive thymidine or by flow cytometry in large numbers of patients. The results show that the DT of human tumor varies widely, from less than one week to over one year with a median value of approximately 2 months. The DTs are significantly correlated with the histological type. They depend upon (1) the duration of the cell cycle whose mean duration is 2 days with small variations from tumor to tumor, (2) the proportion of proliferating cells and consequently the cell birth rate which varies widely among tumors and which is significantly correlated to the DT, (3) the cell loss factors which also vary widely and which are the greatest when proliferation is most intensive. These studies have several clinical implications: (a) they have further increased our understanding of the natural history of human tumor, (b) they have therapeutic implications since tumor responsiveness and curability by radiation and drugs are strongly influenced by the cell kinetic parameters of the tumor, (c) the proportion of proliferating cells is of great prognostic value in several types of human cancers. The investigation of the molecular defects, which are correlated with the perturbation of control of cell proliferation, should lead to significant fundamental and therapeutic advances. (orig.).

  17. Cell proliferation of Paramecium tetraurelia on a slow rotating clinostat

    Science.gov (United States)

    Sawai, Satoe; Mogami, Yoshihiro; Baba, Shoji A.

    Paramecium is known to proliferate faster under microgravity conditions, and slower under hypergravity. Experiments using axenic culture medium have demonstrated that hypergravity affected directly on the proliferation of Paramecium itself. In order to assess the mechanisms underlying the physiological effects of gravity on cell proliferation, Paramecium tetraurelia was grown under clinorotation (2.5 rpm) and the time course of the proliferation was investigated in detail on the basis of the logistic analysis. On the basis of the mechanical properties of Paramecium, this slow rate of the rotation appears to be enough to simulate microgravity in terms of the randomization of the cell orientation with respect to gravity. P. tetraurelia was cultivated in a closed chamber in which cells were confined without air bubbles, reducing the shear forces and turbulences under clinorotation. The chamber is made of quartz and silicone rubber film; the former is for the optically-flat walls for the measurement of cell density by means of a non-invasive laser optical-slice method, and the latter for gas exchange. Because of the small dimension for culture space, Paramecium does not accumulate at the top of the chamber in spite of its known negative gravitactic behavior. We measured the cell density at regular time intervals without breaking the configuration of the chamber, and analyzed the proliferation parameters by fitting the data to a logistic equation. As a result, P. tetraurelia showed reduced proliferation under slow clinorotation. The saturation of the cell density as well as the maximum proliferation rate decreased, although we found no significant changes on the half maximal time for proliferation. We also found that the mean swimming velocity decreased under slow clinorotation. These results were not consistent with those under microgravity and fast rotating clinostat. This may suggest that randomization of the cell orientation performed by slow rotating clinostat has

  18. Cell proliferation of Paramecium tetraurelia under simulated microgravity

    Science.gov (United States)

    Sawai, S.; Mogami, Y.; Baba, S. A.

    Paramecium is known to proliferate faster under microgravity in space and slower under hypergravity Experiments using axenic culture medium have demonstrated that the hypergravity affected directly on the proliferation of Paramecium itself Kato et al 2003 In order to assess the mechanisms underlying the physiological effects of gravity on cell proliferation Paramecium tetraurelia was grown under simulated microgravity performed by clinorotation and the time course of the proliferation was investigated in detail on the basis of the logistic analysis P tetraurelia was cultivated in a closed chamber in which cells were confined without air babbles reducing the shear stresses and turbulence under the rotation The chamber is made of quartz and silicone rubber film the former is for the optically-flat walls for the measurement of cell density by means of a non-invasive laser optical-slice method and the latter for gas exchange Because the closed chamber has an inner dimension of 3 times 3 times 60 mm Paramecium does not accumulate at the top of the chamber despite its negative gravitactic behavior We measured the cell density at regular time intervals without breaking the configuration of the chamber and analyzed the proliferation parameters by fitting the data to a logistic equation Clinorotation had the effects of reducing the proliferation of P tetraurelia It reduced both the saturation cell density and the maximum proliferation rate although it had little effect on the

  19. Expression and function of β-adrenergic receptors in human hematopoietic cell lines

    International Nuclear Information System (INIS)

    Maeki, T.; Andersson, L.C.; Kontula, K.K.

    1992-01-01

    We investigated the expression and functional characteristics of β-adrenoceptors in a panel of 10 phenotypically different human hematopoietic cell lines. A binding assay with [ 125 I]iodocyanopindolol as the ligand revealed that cell lines of myelomonocytic or histiocytic derivation (HL-60, ML-2, RC-2A, U-937) expressed high numbers of β-adrenoceptors. An intermediate density of receptors was found in a non-T, non-B cell leukemia line (Nall-1), whereas T-cell (JM, CCRF-CEM), B-cell (Raji) or erythroleukemic cell lines (K-562, HEL) displayed minimala or undetectable binding of the radioligand. Isoprenaline-stimulated cAMP production by the cells correlated to their extent of β-adrenoceptor expression. Southern blot hybridization analysis of genomic DNA from the cell lines with a 32 P-labelled β 2 -adrenoceptor cDNA probe revealed no evidence for major rearrangement or amplification of the receptor gene. Incubation with isoprenaline in vitro suppressed the proliferation of the receptor-rich RC-2A cells but did not affect the growth rate of the receptor-deficient K-562 cells. Treatment with propranolol slightly enhanced the proliferation of the RC-2A cells but did not markedly alter the growth rate of two other cell lines, regardless of their β-adrenoceptor status. These findings indicate a regulatory influence by the sympathoadrenergic system on selected cells of the myelomonocytic lineage. (au)

  20. Endothelial cell proliferation in swine experimental aneurysm after coil embolization.

    Directory of Open Access Journals (Sweden)

    Yumiko Mitome-Mishima

    Full Text Available After coil embolization, recanalization in cerebral aneurysms adversely influences long-term prognosis. Proliferation of endothelial cells on the coil surface may reduce the incidence of recanalization and further improve outcomes after coil embolization. We aimed to map the expression of proliferating tissue over the aneurysmal orifice and define the temporal profile of tissue growth in a swine experimental aneurysm model. We compared the outcomes after spontaneous thrombosis with those of coil embolization using histological and morphological techniques. In aneurysms that we not coiled, spontaneous thrombosis was observed, and weak, easily detachable proliferating tissue was evident in the aneurysmal neck. In contrast, in the coil embolization group, histological analysis showed endothelial-like cells lining the aneurysmal opening. Moreover, immunohistochemical and morphological analysis suggested that these cells were immature endothelial cells. Our results indicated the existence of endothelial cell proliferation 1 week after coil embolization and showed immature endothelial cells in septal tissue between the systemic circulation and the aneurysm. These findings suggest that endothelial cells are lead to and proliferate in the former aneurysmal orifice. This is the first examination to evaluate the temporal change of proliferating tissue in a swine experimental aneurysm model.

  1. Stimulation of the proliferation of hemopoietic stem cells in irradiated bone marrow cell culture

    International Nuclear Information System (INIS)

    Mori, K.J.; Izumi, H.; Seto, A.

    1981-01-01

    Long-term hemopoiesis was established in bone marrow cell culture in vitro. This culture was shown to support the recovery proliferation of hemopoietic stem cells completely in vitro after irradiation. Hemopoietic stem cells were stimulated into proliferation in culture when normal bone marrow cells were overlayed on top of the irradiated adherent cell colonies. These results indicate that proliferation and differentiation of hemopoietic stem cells in vitro are also supported by stromahemopoietic cell interactions

  2. Differential migration and proliferation of geometrical ensembles of cell clusters

    International Nuclear Information System (INIS)

    Kumar, Girish; Chen, Bo; Co, Carlos C.; Ho, Chia-Chi

    2011-01-01

    Differential cell migration and growth drives the organization of specific tissue forms and plays a critical role in embryonic development, tissue morphogenesis, and tumor invasion. Localized gradients of soluble factors and extracellular matrix have been shown to modulate cell migration and proliferation. Here we show that in addition to these factors, initial tissue geometry can feedback to generate differential proliferation, cell polarity, and migration patterns. We apply layer by layer polyelectrolyte assembly to confine multicellular organization and subsequently release cells to demonstrate the spatial patterns of cell migration and growth. The cell shapes, spreading areas, and cell-cell contacts are influenced strongly by the confining geometry. Cells within geometric ensembles are morphologically polarized. Symmetry breaking was observed for cells on the circular pattern and cells migrate toward the corners and in the direction parallel to the longest dimension of the geometric shapes. This migration pattern is disrupted when actomyosin based tension was inhibited. Cells near the edge or corner of geometric shapes proliferate while cells within do not. Regions of higher rate of cell migration corresponded to regions of concentrated growth. These findings demonstrate that multicellular organization can result in spatial patterns of migration and proliferation.

  3. The importance of the nuclear glutathione in the Cell Proliferation

    OpenAIRE

    Markovic, Jelena

    2009-01-01

    The present thesis offers an insight in the importance of nuclear GSH in cell proliferation. The research was performed in three different cellular models of diverse proliferating activity: immortalized mouse embryonic fibroblasts 3T3, mammary adenocarcinoma cell line MCF7 and primary embryonic neuralonal culture. The results presented here provide evidence that suggest that the relationship between GSH level and telomerase activity, previously described by our group for 3T3 fibroblasts is a ...

  4. Inhibition of brain tumor cell proliferation by alternating electric fields

    International Nuclear Information System (INIS)

    Jeong, Hyesun; Oh, Seung-ick; Hong, Sunghoi; Sung, Jiwon; Jeong, Seonghoon; Yoon, Myonggeun; Koh, Eui Kwan

    2014-01-01

    This study was designed to investigate the mechanism by which electric fields affect cell function, and to determine the optimal conditions for electric field inhibition of cancer cell proliferation. Low-intensity (<2 V/cm) and intermediate-frequency (100–300 kHz) alternating electric fields were applied to glioblastoma cell lines. These electric fields inhibited cell proliferation by inducing cell cycle arrest and abnormal mitosis due to the malformation of microtubules. These effects were significantly dependent on the intensity and frequency of applied electric fields

  5. Inhibition of brain tumor cell proliferation by alternating electric fields

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Hyesun; Oh, Seung-ick; Hong, Sunghoi, E-mail: shong21@korea.ac.kr, E-mail: radioyoon@korea.ac.kr [School of Biosystem and Biomedical Science, Korea University, Seoul 136-703 (Korea, Republic of); Sung, Jiwon; Jeong, Seonghoon; Yoon, Myonggeun, E-mail: shong21@korea.ac.kr, E-mail: radioyoon@korea.ac.kr [Department of Bio-convergence Engineering, Korea University, Seoul 136-703 (Korea, Republic of); Koh, Eui Kwan [Seoul Center, Korea Basic Science Institute, Seoul 136-713 (Korea, Republic of)

    2014-11-17

    This study was designed to investigate the mechanism by which electric fields affect cell function, and to determine the optimal conditions for electric field inhibition of cancer cell proliferation. Low-intensity (<2 V/cm) and intermediate-frequency (100–300 kHz) alternating electric fields were applied to glioblastoma cell lines. These electric fields inhibited cell proliferation by inducing cell cycle arrest and abnormal mitosis due to the malformation of microtubules. These effects were significantly dependent on the intensity and frequency of applied electric fields.

  6. Nicotine as a mitogenic stimulus for pancreatic acinar cell proliferation

    Institute of Scientific and Technical Information of China (English)

    Parimal Chowdhury; Kodetthoor B Udupa

    2006-01-01

    Cell proliferation is an important process in life for growth of normal and cancer cells. The signal transduction pathways activated during this process are strictly regulated. This editorial focuses on the role of nicotine,a mitogen, in the induction of signaling pathways resulting in proliferation of pancreatic tumor cells and compares these events with those in normal acinar cells isolated from the rat pancreas. The data shows striking similarities between these two cellular systems.In addition, the editorial reviews very recent literature of the contribution of MAPK signaling in cell lines associated with human diseases. A prospective cellular model of nicotine induced activation of MAPK cascade is presented.

  7. Scaffold architecture and fibrin gels promote meniscal cell proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Pawelec, K. M., E-mail: pawelec.km@gmail.com, E-mail: jw626@cam.ac.uk; Best, S. M.; Cameron, R. E. [Cambridge Centre for Medical Materials, Materials Science and Metallurgy Department, University of Cambridge, Cambridge CB3 0FS (United Kingdom); Wardale, R. J., E-mail: pawelec.km@gmail.com, E-mail: jw626@cam.ac.uk [Division of Trauma and Orthopaedic Surgery, Department of Surgery, University of Cambridge, Cambridge CB2 2QQ (United Kingdom)

    2015-01-01

    Stability of the knee relies on the meniscus, a complex connective tissue with poor healing ability. Current meniscal tissue engineering is inadequate, as the signals for increasing meniscal cell proliferation have not been established. In this study, collagen scaffold structure, isotropic or aligned, and fibrin gel addition were tested. Metabolic activity was promoted by fibrin addition. Cellular proliferation, however, was significantly increased by both aligned architectures and fibrin addition. None of the constructs impaired collagen type I production or triggered adverse inflammatory responses. It was demonstrated that both fibrin gel addition and optimized scaffold architecture effectively promote meniscal cell proliferation.

  8. EDA-containing fibronectin increases proliferation of embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    Noelia Losino

    Full Text Available Embryonic stem cells (ESC need a set of specific factors to be propagated. They can also grow in conditioned medium (CM derived from a bovine granulosa cell line BGC (BGC-CM, a medium that not only preserves their main features but also increases ESC´s proliferation rate. The mitogenic properties of this medium were previously reported, ascribing this effect to an alternative spliced generated fibronectin isoform that contains the extra domain A (FN EDA(+. Here, we investigated if the FN EDA(+ isoform increased proliferation of mouse and human ES cells. We analyzed cell proliferation using conditioned media produced by different mouse embryonic fibroblast (MEF lines genetically engineered to express FN constitutively including or excluding the EDA domain (FN EDA(-, and in media supplemented with recombinant peptides containing or not the EDA. We found that the presence of EDA in the medium increased mouse and human ESC's proliferation rate. Here we showed for the first time that this FN isoform enhances ESC's proliferation. These findings suggest a possible conserved behavior for regulation of ES cells proliferation by this FN isoform and could contribute to improve their culturing conditions both for research and cell therapy.

  9. Neonatal pancreatic pericytes support β-cell proliferation

    Directory of Open Access Journals (Sweden)

    Alona Epshtein

    2017-10-01

    Conclusions: This study introduces pancreatic pericytes as regulators of neonatal β-cell proliferation. In addition to advancing current understanding of the physiological β-cell replication process, these findings could facilitate the development of protocols aimed at expending these cells as a potential cure for diabetes.

  10. Control mechanisms of cell proliferation in intestinal epithelium

    NARCIS (Netherlands)

    R.P.C. Rijke (Rudy)

    1977-01-01

    textabstractIn the adult organism some organs and tissues still contain proliferating and differentiating cells, whereas other organs only consist of non-dividing specialized cells. On the basis of their proliferative activity cell populations may be classified into three categories (135, 138,208).

  11. Nesfatin-1 inhibits ovarian epithelial carcinoma cell proliferation in vitro

    International Nuclear Information System (INIS)

    Xu, Yang; Pang, Xiaoyan; Dong, Mei; Wen, Fang; Zhang, Yi

    2013-01-01

    Highlights: •Nesfatin-1 inhibits the proliferation and growth of HO-8910 cells by G1 phase arrest. •Nesfatin-1 enhances HO-8910 cell apoptosis. •Nesfatin-1 inhibits HO-8910 cell proliferation via mTOR and RhoA/ROCK signaling pathway. •The first report of nesfatin-1-mediated proliferation in ovarian epithelial carcinoma. -- Abstract: Nesfatin-1, an 82-amino-acid peptide derived from a 396-amino-acid precursor protein nucleobindin 2 (NUCB2), was originally identified in hypothalamic nuclei involved in the regulation of food intake. It was recently reported that nesfatin-1 is a novel depot specific adipokine preferentially produced by subcutaneous tissue, with obesity- and food deprivation-regulated expression. Although a relation between ovarian cancer mortality and obesity has been previously established, a role of nesfatin-1 in ovarian epithelial carcinoma remains unknown. The aim of the present study is to examine the effect of nesfatin-1 on ovary carcinoma cells proliferation. We found that nesfatin-1 inhibits the proliferation and growth of HO-8910 cells by G1 phase arrest, this inhibition could be abolished by nesfatin-1 neutralizing antibody. Nesfatin-1 enhances HO-8910 cell apoptosis, activation of mammalian target of rapamycin (mTOR) and RhoA/ROCK signaling pathway block the effects of nesfatin-1-induced apoptosis, therefore reverses the inhibition of HO-8910 cell proliferation by nesfatin-1. In conclusion, the present study demonstrated that nesfatin-1 can inhibit the proliferation in human ovarian epithelial carcinoma cell line HO-8910 cells through inducing apoptosis via mTOR and RhoA/ROCK signaling pathway. This study provides a novel regulatory signaling pathway of nesfatin-1-regulated ovarian epithelial carcinoma growth and may contribute to ovarian cancer prevention and therapy, especially in obese patients

  12. Nesfatin-1 inhibits ovarian epithelial carcinoma cell proliferation in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Yang; Pang, Xiaoyan; Dong, Mei; Wen, Fang, E-mail: wenfang64@hotmail.com; Zhang, Yi, E-mail: syzi960@yahoo.com

    2013-11-01

    Highlights: •Nesfatin-1 inhibits the proliferation and growth of HO-8910 cells by G1 phase arrest. •Nesfatin-1 enhances HO-8910 cell apoptosis. •Nesfatin-1 inhibits HO-8910 cell proliferation via mTOR and RhoA/ROCK signaling pathway. •The first report of nesfatin-1-mediated proliferation in ovarian epithelial carcinoma. -- Abstract: Nesfatin-1, an 82-amino-acid peptide derived from a 396-amino-acid precursor protein nucleobindin 2 (NUCB2), was originally identified in hypothalamic nuclei involved in the regulation of food intake. It was recently reported that nesfatin-1 is a novel depot specific adipokine preferentially produced by subcutaneous tissue, with obesity- and food deprivation-regulated expression. Although a relation between ovarian cancer mortality and obesity has been previously established, a role of nesfatin-1 in ovarian epithelial carcinoma remains unknown. The aim of the present study is to examine the effect of nesfatin-1 on ovary carcinoma cells proliferation. We found that nesfatin-1 inhibits the proliferation and growth of HO-8910 cells by G1 phase arrest, this inhibition could be abolished by nesfatin-1 neutralizing antibody. Nesfatin-1 enhances HO-8910 cell apoptosis, activation of mammalian target of rapamycin (mTOR) and RhoA/ROCK signaling pathway block the effects of nesfatin-1-induced apoptosis, therefore reverses the inhibition of HO-8910 cell proliferation by nesfatin-1. In conclusion, the present study demonstrated that nesfatin-1 can inhibit the proliferation in human ovarian epithelial carcinoma cell line HO-8910 cells through inducing apoptosis via mTOR and RhoA/ROCK signaling pathway. This study provides a novel regulatory signaling pathway of nesfatin-1-regulated ovarian epithelial carcinoma growth and may contribute to ovarian cancer prevention and therapy, especially in obese patients.

  13. Ubiquitous expression of MAKORIN-2 in normal and malignant hematopoietic cells and its growth promoting activity.

    Directory of Open Access Journals (Sweden)

    King Yiu Lee

    Full Text Available Makorin-2 (MKRN2 is a highly conserved protein and yet its functions are largely unknown. We investigated the expression levels of MKRN2 and RAF1 in normal and malignant hematopoietic cells, and leukemia cell lines. We also attempted to delineate the role of MKRN2 in umbilical cord blood CD34+ stem/progenitor cells and K562 cell line by over-expression and inhibition of MKRN2 through lentivirus transduction and shRNA nucleofection, respectively. Our results provided the first evidence on the ubiquitous expression of MKRN2 in normal hematopoietic cells, embryonic stem cell lines, primary leukemia and leukemic cell lines of myeloid, lymphoid, erythroid and megakaryocytic lineages. The expression levels of MKRN2 were generally higher in primary leukemia samples compared with those in age-matched normal BM cells. In all leukemia subtypes, there was no significant correlation between expression levels of MKRN2 and RAF1. sh-MKRN2-silenced CD34+ cells had a significantly lower proliferation capacity and decreased levels of the early stem/progenitor subpopulation (CFU-GEMM compared with control cultures. Over-expression of MKRN2 in K562 cells increased cell proliferation. Our results indicated possible roles of MKRN2 in normal and malignant hematopoiesis.

  14. α-Ketoglutarate Promotes Pancreatic Progenitor-Like Cell Proliferation

    Directory of Open Access Journals (Sweden)

    Jing Song

    2018-03-01

    Full Text Available A major source of β cell generation is pancreatic progenitor-like cell differentiation. Multiple studies have confirmed that stem cell metabolism plays important roles in self-renewal and proliferation. In the absence of glucose, glutamine provides the energy for cell division and growth. Furthermore, α-ketoglutarate (αKG, a precursor for glutamine synthesis, is sufficient for enabling glutamine-independent cell proliferation. We have demonstrated that αKG contributes to the large-scale proliferation of pancreatic progenitor-like cells that can provide an ample amount of clinically relevant β cells. We compared the mRNA expression of a subset of genes, the abundance of ATP, reactive oxide species, mitochondrial number, and the colony-forming frequency between mouse pancreatic CD133+ and CD133− cells. We employed Real-Time PCR, immunostaining and passage assays to investigate self-renewal and proliferation of pancreatic progenitor-like cells in a 3D culture system in the presence and absence of αKG. The energy metabolism of CD133+ cells was more prone to oxidative phosphorylation. However, in the 3D culture system, when αKG was supplemented to the culture medium, the proliferation of the pancreatic progenitor-like cells was significantly elevated. We confirmed that the presence of αKG correlated with the up-regulation of Ten-Eleven Translocation (Tet. αKG can promote the proliferation of pancreatic progenitor-like cells via the up-regulation of Tet.

  15. α-Ketoglutarate Promotes Pancreatic Progenitor-Like Cell Proliferation.

    Science.gov (United States)

    Song, Jing; Ma, Dongshen; Xing, Yun; Tang, Shanshan; Alahdal, Murad; Guo, Jiamin; Pan, Yi; Zhang, Yanfeng; Shen, Yumeng; Wu, Qiong; Lu, Zhou; Jin, Liang

    2018-03-22

    A major source of β cell generation is pancreatic progenitor-like cell differentiation. Multiple studies have confirmed that stem cell metabolism plays important roles in self-renewal and proliferation. In the absence of glucose, glutamine provides the energy for cell division and growth. Furthermore, α-ketoglutarate (αKG), a precursor for glutamine synthesis, is sufficient for enabling glutamine-independent cell proliferation. We have demonstrated that αKG contributes to the large-scale proliferation of pancreatic progenitor-like cells that can provide an ample amount of clinically relevant β cells. We compared the mRNA expression of a subset of genes, the abundance of ATP, reactive oxide species, mitochondrial number, and the colony-forming frequency between mouse pancreatic CD133⁺ and CD133 - cells. We employed Real-Time PCR, immunostaining and passage assays to investigate self-renewal and proliferation of pancreatic progenitor-like cells in a 3D culture system in the presence and absence of αKG. The energy metabolism of CD133⁺ cells was more prone to oxidative phosphorylation. However, in the 3D culture system, when αKG was supplemented to the culture medium, the proliferation of the pancreatic progenitor-like cells was significantly elevated. We confirmed that the presence of αKG correlated with the up-regulation of Ten-Eleven Translocation (Tet). αKG can promote the proliferation of pancreatic progenitor-like cells via the up-regulation of Tet.

  16. Proliferation of differentiated glial cells in the brain stem

    Directory of Open Access Journals (Sweden)

    P.C. Barradas

    1998-02-01

    Full Text Available Classical studies of macroglial proliferation in muride rodents have provided conflicting evidence concerning the proliferating capabilities of oligodendrocytes and microglia. Furthermore, little information has been obtained in other mammalian orders and very little is known about glial cell proliferation and differentiation in the subclass Metatheria although valuable knowledge may be obtained from the protracted period of central nervous system maturation in these forms. Thus, we have studied the proliferative capacity of phenotypically identified brain stem oligodendrocytes by tritiated thymidine radioautography and have compared it with known features of oligodendroglial differentiation as well as with proliferation of microglia in the opossum Didelphis marsupialis. We have detected a previously undescribed ephemeral, regionally heterogeneous proliferation of oligodendrocytes expressing the actin-binding, ensheathment-related protein 2'3'-cyclic nucleotide 3'-phosphodiesterase (CNPase, that is not necessarily related to the known regional and temporal heterogeneity of expression of CNPase in cell bodies. On the other hand, proliferation of microglia tagged by the binding of Griffonia simplicifolia B4 isolectin, which recognizes an alpha-D-galactosyl-bearing glycoprotein of the plasma membrane of macrophages/microglia, is known to be long lasting, showing no regional heterogeneity and being found amongst both ameboid and differentiated ramified cells, although at different rates. The functional significance of the proliferative behavior of these differentiated cells is unknown but may provide a low-grade cell renewal in the normal brain and may be augmented under pathological conditions.

  17. 7-Piperazinethylchrysin inhibits melanoma cell proliferation by ...

    African Journals Online (AJOL)

    PEC) on melanoma cell lines. Methods: Cell viability was analyzed by trypan blue exclusion assays and the cell cycle by flow cytometry using ModFit LT software. Specifically, cells were stained with propidium iodide (0.5 mg/mL) supplemented ...

  18. Cell cycles and proliferation patterns in Haematococcus pluvialis

    Science.gov (United States)

    Zhang, Chunhui; Liu, Jianguo; Zhang, Litao

    2017-09-01

    Most studies on Haematococcus pluvialis have been focused on cell growth and astaxanthin accumulation; far less attention has been paid to cell cycles and proliferation patterns. The purpose of this study was to clarify cell cycles and proliferation patterns in H. pluvialis microscopically using a camera and video recorder system. The complicated life history of H. pluvialis can be divided into two stages: the motile stage and the non-motile stage. All the cells can be classified into forms as follows: motile cell, nonmotile cell, zoospore and aplanospore. The main cell proliferation, both in the motile phase and non-motile phase in H. pluvialis, is by asexual reproduction. Under normal growth conditions, a motile cell usually produces two, sometimes four, and exceptionally eight zoospores. Under unfavorable conditions, the motile cell loses its flagella and transforms into a non-motile cell, and the non-motile cell usually produces 2, 4 or 8 aplanospores, and occasionally 20-32 aplanospores, which further develop into non-motile cells. Under suitable conditions, the non-motile cell is also able to release zoospores. The larger non-motile cells produce more than 16 zoospores, and the smaller ones produce 4 or 8 zoospores. Vegetative reproduction is by direct cell division in the motile phase and by occasional cell budding in the non-motile phase. There is, as yet, no convincing direct evidence for sexual reproduction.

  19. Prostaglandins with antiproliferative activity induce the synthesis of a heat shock protein in human cells

    International Nuclear Information System (INIS)

    Santoro, M.G.; Garaci, E.; Amici, C.

    1989-01-01

    Prostaglandins (PGs)A 1 and J 2 were found to potently suppress the proliferation of human K562 erythroleukemia cells and to induce the synthesis of a 74-kDa protein (p74) that was identified as a heat shock protein related to the major 70-kDa heat shock protein group. p74 synthesis was stimulated at doses of PGA 1 and PGJ 2 that inhibited cell replication, and its accumulation ceased upon removal of the PG-induced proliferation block. PGs that did not affect K562 cell replication did not induce p74 synthesis. p74 was found to be localized mainly in the cytoplasm of PG-treated cells, but moderate amounts were found also in dense areas of the nucleus after PGJ 2 treatment. p74 was not necessarily associated with cytotoxicity or with inhibition of cell protein synthesis. The results described support the hypothesis that synthesis of the 70-kDa heat shock proteins is associated with changes in cell proliferation. The observation that PGs can induce the synthesis of heat shock proteins expands our understanding of the mechanism of action of these compounds whose regulatory role is well known in many physiological phenomena, including the control of fever production

  20. SOX15 regulates proliferation and migration of endometrial cancer cells.

    Science.gov (United States)

    Rui, Xiaohui; Xu, Yun; Jiang, Xiping; Guo, Caixia; Jiang, Jingting

    2017-10-31

    The study aimed to investigate the effects of Sry-like high mobility group box 15 ( SOX15 ) on proliferation and migration of endometrial cancer (EC) cells. Immunohistochemistry (IHC) was applied to determine the expression of SOX15 in EC tissues and adjacent tissues. We used cell transfection method to construct the HEC-1-A and Ishikawa cell lines with stable overexpression and low expression SOX15 Reverse-transcription quantitative real-time PCR (RT-qPCR) and Western blot were performed to examine expression of SOX15 mRNA and SOX15 protein, respectively. By conducting a series of cell proliferation assay and migration assay, we analyzed the influence of SOX15 overexpression or low expression on EC cell proliferation and migration. The expression of SOX15 mRNA and protein in EC tissues was significantly lower than that in adjacent tissues. After lentivirus-transfecting SOX15 , the expression level of SOX15 mRNA and protein was significantly increased in cells of SOX15 group, and decreased in sh- SOX15 group. Overexpression of SOX15 could suppress cell proliferation, while down-regulation of SOX15 increased cell proliferation. Flow cytometry results indicated that overexpression of SOX15 induced the ratio of cell-cycle arrest in G 1 stage. In addition, Transwell migration assay results showed that SOX15 overexpression significantly inhibited cell migration, and also down-regulation of SOX15 promoted the migration. As a whole, SOX15 could regulate the proliferation and migration of EC cells and up- regulation of SOX15 could be valuable for EC treatment. © 2017 The Author(s).

  1. The geometry of proliferating dicot cells.

    Science.gov (United States)

    Korn, R W

    2001-02-01

    The distributions of cell size and cell cycle duration were studied in two-dimensional expanding plant tissues. Plastic imprints of the leaf epidermis of three dicot plants, jade (Crassula argentae), impatiens (Impatiens wallerana), and the common begonia (Begonia semperflorens) were made and cell outlines analysed. The average, standard deviation and coefficient of variance (CV = 100 x standard deviation/average) of cell size were determined with the CV of mother cells less than the CV for daughter cells and both are less than that for all cells. An equation was devised as a simple description of the probability distribution of sizes for all cells of a tissue. Cell cycle durations as measured in arbitrary time units were determined by reconstructing the initial and final sizes of cells and they collectively give the expected asymmetric bell-shaped probability distribution. Given the features of unequal cell division (an average of 11.6% difference in size of daughter cells) and the size variation of dividing cells, it appears that the range of cell size is more critically regulated than the size of a cell at any particular time.

  2. Dictyostelium cells bind a secreted autocrine factor that represses cell proliferation

    OpenAIRE

    Choe, Jonathan M; Bakthavatsalam, Deenadayalan; Phillips, Jonathan E; Gomer, Richard H

    2009-01-01

    Abstract Background Dictyostelium cells secrete the proteins AprA and CfaD. Cells lacking either AprA or CfaD proliferate faster than wild type, while AprA or CfaD overexpressor cells proliferate slowly, indicating that AprA and CfaD are autocrine factors that repress proliferation. CfaD interacts with AprA and requires the presence of AprA to slow proliferation. To determine if CfaD is necessary for the ability of AprA to slow proliferation, whether AprA binds to cells, and if so whether the...

  3. Monovalent ions control proliferation of Ehrlich Lettre ascites cells

    DEFF Research Database (Denmark)

    Klausen, Thomas Kjaer; Preisler, Sarah; Pedersen, Stine Helene Falsig

    2010-01-01

    of Ehrlich Lettre ascites (ELA) cells. We measured the intracellular concentration of each ion in G(0), G(1), and S phases of the cell cycle following synchronization by serum starvation and release. We show that intracellular concentrations and content of Na+ and Cl(-) were reduced in the G(0)-G(1) phase...... effect. Western blots showed reduced chloride intracellular channel CLIC1 and chloride channel ClC-2 expression in the plasma membrane in S compared with G(1). Our results suggest that Na+ regulates ELA cell proliferation by regulating intracellular pH while Cl(-) may regulate proliferation by fine...

  4. Cell proliferation and radiosensitivity of cow lymphocytes in culture

    International Nuclear Information System (INIS)

    Modave, C.; Fabry, L.; Leonard, A.

    1982-01-01

    The harlequin-staining technique has been used to study, after PHA-stimulation, the cell proliferation of cow lymphocytes in culture and to assess the radiosensitivity in first mitosis cells. At the 48 h fixation time, only 34% of the cells are in first mitosis whereas 55% are already in second and 11% in third mitosis. The exposure of cow lymphocytes to 200 rad X-rays result in the production of 16% dicentric chromosomes in first mitosis cells [fr

  5. Chloroquinone Inhibits Cell Proliferation and Induces Apoptosis in ...

    African Journals Online (AJOL)

    Purpose: To demonstrate the role of chloroquinone (CQ) in inducing apoptosis in HONE-1 and HNE-1, nasopharyngeal carcinoma (NPC) cell lines. Methods: Water-soluble tetrazolium salt (WST)-1 assay was used for the determination of cell proliferation while an inverted microscope was employed for the analysis of ...

  6. Polybrene inhibits human mesenchymal stem cell proliferation during lentiviral transduction.

    Directory of Open Access Journals (Sweden)

    Paul Lin

    Full Text Available Human mesenchymal stem cells (hMSCs can be engineered to express specific genes, either for their use in cell-based therapies or to track them in vivo over long periods of time. To obtain long-term expression of these genes, a lentivirus- or retrovirus-mediated cell transduction is often used. However, given that the efficiency with these viruses is typically low in primary cells, additives such as polybrene are always used for efficient viral transduction. Unfortunately, as presented here, exposure to polybrene alone at commonly used concentratons (1-8 µg/mL negatively impacts hMSC proliferation in a dose-dependent manner as measured by CyQUANT, EdU incorporation, and cell cycle analysis. This inhibition of proliferation was observable in culture even 3 weeks after exposure. Culturing the cells in the presence of FGF-2, a potent mitogen, did not abrogate this negative effect of polybrene. In fact, the normally sharp increase in hMSC proliferation that occurs during the first days of exposure to FGF-2 was absent at 4 µg/mL or higher concentrations of polybrene. Similarly, the effect of stimulating cell proliferation under simulated hypoxic conditions was also decreased when cells were exposed to polybrene, though overall proliferation rates were higher. The negative influence of polybrene was, however, reduced when the cells were exposed to polybrene for a shorter period of time (6 hr vs 24 hr. Thus, careful evaluation should be done when using polybrene to aid in lentiviral transduction of human MSCs or other primary cells, especially when cell number is critical.

  7. Controling stem cell proliferation - CKIs at work

    NARCIS (Netherlands)

    Bruggeman, SWM; van Lohuizen, M

    2006-01-01

    The cyclin-dependent kinase inhibitors or CKIs are well recognized as intrinsic regulators of the cell cycle. Here, we discuss recent data implicating their activity in restraining adult stem cell self-renewal, and the role that proteins regulating CKI expression play in this process.

  8. Software for precise tracking of cell proliferation

    International Nuclear Information System (INIS)

    Kurokawa, Hiroshi; Noda, Hisayori; Sugiyama, Mayu; Sakaue-Sawano, Asako; Fukami, Kiyoko; Miyawaki, Atsushi

    2012-01-01

    Highlights: ► We developed software for analyzing cultured cells that divide as well as migrate. ► The active contour model (Snakes) was used as the core algorithm. ► The time backward analysis was also used for efficient detection of cell division. ► With user-interactive correction functions, the software enables precise tracking. ► The software was successfully applied to cells with fluorescently-labeled nuclei. -- Abstract: We have developed a multi-target cell tracking program TADOR, which we applied to a series of fluorescence images. TADOR is based on an active contour model that is modified in order to be free of the problem of locally optimal solutions, and thus is resistant to signal fluctuation and morphological changes. Due to adoption of backward tracing and addition of user-interactive correction functions, TADOR is used in an off-line and semi-automated mode, but enables precise tracking of cell division. By applying TADOR to the analysis of cultured cells whose nuclei had been fluorescently labeled, we tracked cell division and cell-cycle progression on coverslips over an extended period of time.

  9. Emodin downregulates cell proliferation markers during DMBA ...

    African Journals Online (AJOL)

    Background: Cell-cycle disruption is the major characteristic features of neoplastic transformation and the status of cell-cycle regulators can thus be utilized to assess the prognostic significance in patients with cancer. The PCNA, cyclin D1, CDK4, CDK6 and survivin expression in the buccal mucosa was utilized to evaluate ...

  10. Beta cell proliferation and growth factors

    DEFF Research Database (Denmark)

    Nielsen, Jens Høiriis; Svensson, C; Møldrup, Annette

    1999-01-01

    Formation of new beta cells can take place by two pathways: replication of already differentiated beta cells or neogenesis from putative islet stem cells. Under physiological conditions both processes are most pronounced during the fetal and neonatal development of the pancreas. In adulthood little...... increase in the beta cell number seems to occur. In pregnancy, however, a marked hyperplasia of the beta cells is observed both in rodents and man. Increased mitotic activity has been seen both in vivo and in vitro in islets exposed to placental lactogen (PL), prolactin (PRL) and growth hormone (GH...... and activation of the tyrosine kinase JAK2 and the transcription factors STAT1 and 3. The activation of the insulin gene however also requires the distal part of the receptor and activation of calcium uptake and STAT5. In order to identify putative autocrine growth factors or targets for growth factors we have...

  11. Reciprocal control of cell proliferation and migration

    Directory of Open Access Journals (Sweden)

    De Donatis Alina

    2010-09-01

    Full Text Available Abstract In adult tissue the quiescent state of a single cell is maintained by the steady state conditions of its own microenvironment for what concern both cell-cell as well as cell-ECM interaction and soluble factors concentration. Physiological or pathological conditions can alter this quiescent state through an imbalance of both soluble and insoluble factors that can trigger a cellular phenotypic response. The kind of cellular response depends by many factors but one of the most important is the concentration of soluble cytokines sensed by the target cell. In addition, due to the intrinsic plasticity of many cellular types, every single cell is able, in response to the same stimulus, to rapidly switch phenotype supporting minimal changes of microenviromental cytokines concentration. Wound healing is a typical condition in which epithelial, endothelial as well as mesenchymal cells are firstly subjected to activation of their motility in order to repopulate the damaged region and then they show a strong proliferative response in order to successfully complete the wound repair process. This schema constitute the leitmotif of many other physiological or pathological conditions such as development vasculogenesis/angiogenesis as well as cancer outgrowth and metastasis. Our review focuses on the molecular mechanisms that control the starting and, eventually, the switching of cellular phenotypic outcome in response to changes in the symmetry of the extracellular environment.

  12. Automated measurement of cell motility and proliferation

    Directory of Open Access Journals (Sweden)

    Goff Julie

    2005-04-01

    Full Text Available Abstract Background Time-lapse microscopic imaging provides a powerful approach for following changes in cell phenotype over time. Visible responses of whole cells can yield insight into functional changes that underlie physiological processes in health and disease. For example, features of cell motility accompany molecular changes that are central to the immune response, to carcinogenesis and metastasis, to wound healing and tissue regeneration, and to the myriad developmental processes that generate an organism. Previously reported image processing methods for motility analysis required custom viewing devices and manual interactions that may introduce bias, that slow throughput, and that constrain the scope of experiments in terms of the number of treatment variables, time period of observation, replication and statistical options. Here we describe a fully automated system in which images are acquired 24/7 from 384 well plates and are automatically processed to yield high-content motility and morphological data. Results We have applied this technology to study the effects of different extracellular matrix compounds on human osteoblast-like cell lines to explore functional changes that may underlie processes involved in bone formation and maintenance. We show dose-response and kinetic data for induction of increased motility by laminin and collagen type I without significant effects on growth rate. Differential motility response was evident within 4 hours of plating cells; long-term responses differed depending upon cell type and surface coating. Average velocities were increased approximately 0.1 um/min by ten-fold increases in laminin coating concentration in some cases. Comparison with manual tracking demonstrated the accuracy of the automated method and highlighted the comparative imprecision of human tracking for analysis of cell motility data. Quality statistics are reported that associate with stage noise, interference by non-cell

  13. Development of bioengineering system for stem cell proliferation

    Science.gov (United States)

    Park, H. S.; Shah, R.; Shah, C.

    2016-08-01

    From last decades, intensive research in the field of stem cells proliferation had been promoted due to the unique property of stem cells to self-renew themselves into multiples and has potential to replicate into an organ or tissues and so it's highly demanding though challenging. Bioreactor, a mechanical device, works as a womb for stem cell proliferation by providing nutritious environment for the proper growth of stem cells. Various factors affecting stem cells growth are the bioreactor mechanism, feeding of continuous nutrients, healthy environment, etc., but it always remains a challenge for controlling biological parameters. The present paper unveils the design of mechanical device commonly known as bioreactor in tissues engineering and biotech field, use for proliferation of stem cells and imparts the proper growing condition for stem cells. This high functional bioreactor provides automation mixing of cell culture and stem cells. This design operates in conjunction with mechanism of reciprocating motion. Compare to commercial bioreactors, this proposed design is more convenient, easy to operate and less maintenance is required as bioreactor culture bag is made of polyethylene which is single use purpose. Development of this bioengineering system will be beneficial for better growth and expansion of stem cell

  14. Role of Dicer1 in thyroid cell proliferation and differentiation.

    Science.gov (United States)

    Penha, Ricardo Cortez Cardoso; Sepe, Romina; De Martino, Marco; Esposito, Francesco; Pellecchia, Simona; Raia, Maddalena; Del Vecchio, Luigi; Decaussin-Petrucci, Myriam; De Vita, Gabriella; Pinto, Luis Felipe Ribeiro; Fusco, Alfredo

    2017-01-01

    DICER1 plays a central role in the biogenesis of microRNAs and it is important for normal development. Altered microRNA expression and DICER1 dysregulation have been described in several types of tumors, including thyroid carcinomas. Recently, our group identified a new somatic mutation (c.5438A>G; E1813G) within DICER1 gene of an unknown function. Herein, we show that DICER1 is overexpressed, at mRNA level, in a significant-relative number of papillary (70%) and anaplastic (42%) thyroid carcinoma samples, whereas is drastically downregulated in all the analyzed human thyroid carcinoma cell lines (TPC-1, BCPAP, FRO and 8505c) in comparison with normal thyroid tissue samples. Conversely, DICER1 is downregulated, at protein level, in PTC in comparison with normal thyroid tissues. Our data also reveals that DICER1 overexpression positively regulates thyroid cell proliferation, whereas its silencing impairs thyroid cell differentiation. The expression of DICER1 gene mutation (c.5438A>G; E1813G) negatively affects the microRNA machinery and cell proliferation as well as upregulates DICER1 protein levels of thyroid cells but has no impact on thyroid differentiation. In conclusion, DICER1 protein is downregulated in papillary thyroid carcinomas and affects thyroid proliferation and differentiation, while DICER1 gene mutation (c.5438A>G; E1813G) compromises the DICER1 wild-type-mediated microRNA processing and cell proliferation.

  15. Transient processes in cell proliferation kinetics

    CERN Document Server

    Yakovlev, Andrej Yu

    1989-01-01

    A mathematician who has taken the romantic decision to devote himself to biology will doubtlessly look upon cell kinetics as the most simple and natural field of application for his knowledge and skills. Indeed, the thesaurus he is to master is not so complicated as, say, in molecular biology, the structural elements of the system, i. e. ceils, have been segregated by Nature itself, simple considerations of balance may be used for deducing basic equations, and numerous analogies in other areas of science also superficial add to one"s confidence. Generally speaking, this number of impression is correct, as evidenced by the very great theoretical studies on population kinetics, unmatched in other branches of mathematical biology. This, however, does not mean that mathematical theory of cell systems has traversed in its development a pathway free of difficulties or errors. The seeming ease of formalizing the phenomena of cell kinetics not infrequently led to the appearance of mathematical models lacking in adequ...

  16. Cell kinetics of irradiated experimental tumors: cell transition from the non-proliferating to the proliferating pool

    International Nuclear Information System (INIS)

    Potmesil, M.; Goldfeder, A.

    1980-01-01

    In murine mammary carcinomas, parenchymal tumor cells with dense nucleoli traverse the cell cycle and divide, thus constituting the proliferating pool. Cells with trabeculate or ring-shaped nucleoli either proceed slowly through G 1 phase or are arrested in it. The role of these non-proliferating, G 1 phase-confined cells in tumor regeneration was studied in vivo after a subcurative dose of X-irradiation in two transplantable tumor lines. Tumor-bearing mice were continuously injected with methyl[ 3 H]thymidine before and after irradiation. Finally, the labeling was discontinued, mice injected with vincristine sulfate and cells arrested in metaphase were accumulated over 10-hrs. Two clearly delineated groups of vincristine-arrested mitoses emerged in autoradiograms prepared from tumor tissue at the time of starting tumor regrowth: one group with the silver-grain counts corresponding to the background level, the other with heavily labeled mitoses. As the only source of unlabeled mitoses was unlabeled G 1 phase-confined cells persisting in the tumor, this indicated cell transition from the non-proliferating to the proliferating pool, which took place in the initial phase of the tumor regrowth. Unlabeled progenitors have apparently remained in G 1 phase for at least 5-12 days after irradiation. (author)

  17. Glutathione, cell proliferation and differentiation | Ashtiani | African ...

    African Journals Online (AJOL)

    All organisms require an equivalent source for living. Reduced glutathione is the most abundant thiol containing protein in mammalian cells and organs. Glutathione was discovered by Hopkins in 1924 who published his findings in JBC. It is a three peptide containing glutamic acid, cystein and glycin and is found in reduced ...

  18. FOXL2-induced follistatin attenuates activin A-stimulated cell proliferation in human granulosa cell tumors

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Jung-Chien; Chang, Hsun-Ming; Qiu, Xin; Fang, Lanlan; Leung, Peter C.K., E-mail: peter.leung@ubc.ca

    2014-01-10

    Highlights: •Activin A stimulates cell proliferation in KGN human granulosa cell tumor-derived cell line. •Cyclin D2 mediates activin A-induced KGN cell proliferation. •FOXL2 induces follistatin expression in KGN cells. •FOXL2-induced follistatin attenuates activin A-stimulated KGN cell proliferation. -- Abstract: Human granulosa cell tumors (GCTs) are rare, and their etiology remains largely unknown. Recently, the FOXL2 402C > G (C134W) mutation was found to be specifically expressed in human adult-type GCTs; however, its function in the development of human GCTs is not fully understood. Activins are members of the transforming growth factor-beta superfamily, which has been shown to stimulate normal granulosa cell proliferation; however, little is known regarding the function of activins in human GCTs. In this study, we examined the effect of activin A on cell proliferation in the human GCT-derived cell line KGN. We show that activin A treatment stimulates KGN cell proliferation. Treatment with the activin type I receptor inhibitor SB431542 blocks activin A-stimulated cell proliferation. In addition, our results show that cyclin D2 is induced by treatment with activin A and is involved in activin A-stimulated cell proliferation. Moreover, the activation of Smad signaling is required for activin A-induced cyclin D2 expression. Finally, we show that the overexpression of the wild-type FOXL2 but not the C134W mutant FOXL2 induced follistatin production. Treatment with exogenous follistatin blocks activin A-stimulated cell proliferation, and the overexpression of wild-type FOXL2 attenuates activin A-stimulated cell proliferation. These results suggest that FOXL2 may act as a tumor suppressor in human adult-type GCTs by inducing follistatin expression, which subsequently inhibits activin-stimulated cell proliferation.

  19. Amniotic Fluid Cells Proliferation in Normal and Down Syndrome Subjects

    Directory of Open Access Journals (Sweden)

    Honcea Adina

    2016-02-01

    Full Text Available Down Syndrome/Trisomy 21 is the most common chromosomal anomaly, and it represents the most common congenital cause of infants’ intellectual disability. Subjects with this syndrome are affected by degenerative processes caused by accelerated aging or unknown ethyologies. In recent years, accumulating evidence revealed increased potential of amniotic fluid-derived stem cells to be used in regenerative therapy. Our aim was to assess differences in immunophenotype, cell morphology and proliferation of amniotic fluid cells from normal and Down Syndrome pregnancies using a quantitative cytometry approach. Results revealed the emergence of a population of small sized cells in Down Syndrome derived amniotic fluid cells that are readily visible upon microscopic inspection. Hence, the fluorescence–based quantitative image cytometry determinations showed a tendency of decrease in both cell and nuclei size in trisomy, with no significant modification in nuclei circularity, as measured following actin cytoskeleton and nuclei labeling. The propensity of Ki67 positive cells was found to be increased in Down Syndrome derived cells (48.92% as compared to normal specimens (28.68%. However, cells in S and G2/M cell cycle phases decreased from 32.91% to 4.49% in diseased cells. Further studies are devoted to understanding the molecular basis of the observed differences in the proliferation ability of Down Syndrome amniotic cells, in order to evaluate the potential therapeutic effect of amniotic fluid stem cells for tissue regeneration in subjects with trisomy and to find correlations between amniotic cells phenotype and patient prognosis.

  20. Black cohosh inhibits 17β-estradiol-induced cell proliferation of endometrial adenocarcinoma cells.

    Science.gov (United States)

    Park, So Yun; Kim, Hee Ja; Lee, Sa Ra; Choi, Youn-Hee; Jeong, Kyungah; Chung, Hyewon

    2016-10-01

    This study was conducted to investigate the effect of black cohosh (BC) extract on the proliferation and apoptosis of Ishikawa cells. Ishikawa human endometrial adenocarcinoma cells were treated with or without BC (1, 5, 10 and 25 μM) and cell proliferation and cytotoxicity were measured by CCK-8 assays and flow cytometry analysis. Additionally, Ishikawa cells were treated with 17β-estradiol (E2), E2 + progesterone and E2 + BC (5 and 10 μM) and the effect of BC and progesterone on E2-induced cell proliferation was analyzed. BC decreased the proliferation of Ishikawa cells at a dose-dependent rate compared with the control group (p < 0.05). The proliferation of Ishikawa cells increased in the presence of E2, whereas the subsequent addition of progesterone or BC decreased proliferation to the level of the control group (p < 0.05). The inhibitory effect of BC on E2-induced cell proliferation was greater than the inhibitory effect of progesterone. In conclusion, BC induces apoptosis in Ishikawa cells and suppresses E2-induced cell proliferation in Ishikawa cells. BC could be considered a candidate co-treatment agent of estrogen-dependent tumors, especially those involving endometrial cells.

  1. Comparison of the circadian variation in cell proliferation in normal and neoplastic colonic epithelial cells.

    Science.gov (United States)

    Kennedy, M F; Tutton, P J; Barkla, D H

    1985-09-15

    Circadian variations in cell proliferation in normal tissues have been recognised for many years but comparable phenomena in neoplastic tissues appear not to have been reported. Adenomas and carcinomas were induced in mouse colon by injection of dimethylhydrazine (DMH) and cell proliferation in these tumors was measured stathmokinetically. In normal intestine cell proliferation is fastest at night whereas in both adenomas and carcinomas it was found to be slower at night than in the middle of the day. Chemical sympathectomy was found to abolish the circadian variation in tumor cell proliferation.

  2. Poisson-event-based analysis of cell proliferation.

    Science.gov (United States)

    Summers, Huw D; Wills, John W; Brown, M Rowan; Rees, Paul

    2015-05-01

    A protocol for the assessment of cell proliferation dynamics is presented. This is based on the measurement of cell division events and their subsequent analysis using Poisson probability statistics. Detailed analysis of proliferation dynamics in heterogeneous populations requires single cell resolution within a time series analysis and so is technically demanding to implement. Here, we show that by focusing on the events during which cells undergo division rather than directly on the cells themselves a simplified image acquisition and analysis protocol can be followed, which maintains single cell resolution and reports on the key metrics of cell proliferation. The technique is demonstrated using a microscope with 1.3 μm spatial resolution to track mitotic events within A549 and BEAS-2B cell lines, over a period of up to 48 h. Automated image processing of the bright field images using standard algorithms within the ImageJ software toolkit yielded 87% accurate recording of the manually identified, temporal, and spatial positions of the mitotic event series. Analysis of the statistics of the interevent times (i.e., times between observed mitoses in a field of view) showed that cell division conformed to a nonhomogeneous Poisson process in which the rate of occurrence of mitotic events, λ exponentially increased over time and provided values of the mean inter mitotic time of 21.1 ± 1.2 hours for the A549 cells and 25.0 ± 1.1 h for the BEAS-2B cells. Comparison of the mitotic event series for the BEAS-2B cell line to that predicted by random Poisson statistics indicated that temporal synchronisation of the cell division process was occurring within 70% of the population and that this could be increased to 85% through serum starvation of the cell culture. © 2015 International Society for Advancement of Cytometry.

  3. Antiproliferative Effects of Bacillus coagulans Unique IS2 in Colon Cancer Cells.

    Science.gov (United States)

    Madempudi, Ratna Sudha; Kalle, Arunasree M

    2017-10-01

    In the present study, the in vitro anticancer (antiproliferative) effects of Bacillus coagulans Unique IS2 were evaluated on human colon cancer (COLO 205), cervical cancer (HeLa), and chronic myeloid leukemia (K562) cell lines with a human embryonic kidney cell line (HEK 293T) as noncancerous control cells. The Cytotoxicity assay (MTT) clearly demonstrated a 22%, 31.7%, and 19.5% decrease in cell proliferation of COLO 205, HeLa, and K562 cells, respectively, when compared to the noncancerous HEK 293T cells. Normal phase-contrast microscopic images clearly suggested that the mechanism of cell death is by apoptosis. To further confirm the induction of apoptosis by Unique IS2, the sub-G0-G1 peak of the cell cycle was quantified using a flow cytometer and the data indicated 40% of the apoptotic cells in Unique IS2-treated COLO cells when compared with their untreated control cells. The Western blot analysis showed an increase in pro-apoptotic protein BAX, decrease in antiapoptotic protein, Bcl2, decrease in mitochondrial membrane potential, increase in cytochrome c release, increase in Caspase 3 activity, and cleavage of poly(ADP-ribose) polymerase. The present study suggests that the heat-killed culture supernatant of B. coagulans can be more effective in inducing apoptosis of colon cancer cells and that can be considered for adjuvant therapy in the treatment of colon carcinoma.

  4. Proliferation of Genetically Modified Human Cells on Electrospun Nanofiber Scaffolds

    Directory of Open Access Journals (Sweden)

    Mandula Borjigin

    2012-01-01

    Full Text Available Gene editing is a process by which single base mutations can be corrected, in the context of the chromosome, using single-stranded oligodeoxynucleotides (ssODNs. The survival and proliferation of the corrected cells bearing modified genes, however, are impeded by a phenomenon known as reduced proliferation phenotype (RPP; this is a barrier to practical implementation. To overcome the RPP problem, we utilized nanofiber scaffolds as templates on which modified cells were allowed to recover, grow, and expand after gene editing. Here, we present evidence that some HCT116-19, bearing an integrated, mutated enhanced green fluorescent protein (eGFP gene and corrected by gene editing, proliferate on polylysine or fibronectin-coated polycaprolactone (PCL nanofiber scaffolds. In contrast, no cells from the same reaction protocol plated on both regular dish surfaces and polylysine (or fibronectin-coated dish surfaces proliferate. Therefore, growing genetically modified (edited cells on electrospun nanofiber scaffolds promotes the reversal of the RPP and increases the potential of gene editing as an ex vivo gene therapy application.

  5. Estimation of Cell Proliferation Dynamics Using CFSE Data

    Science.gov (United States)

    Banks, H.T.; Sutton, Karyn L.; Thompson, W. Clayton; Bocharov, Gennady; Roose, Dirk; Schenkel, Tim; Meyerhans, Andreas

    2010-01-01

    Advances in fluorescent labeling of cells as measured by flow cytometry have allowed for quantitative studies of proliferating populations of cells. The investigations (Luzyanina et al. in J. Math. Biol. 54:57–89, 2007; J. Math. Biol., 2009; Theor. Biol. Med. Model. 4:1–26, 2007) contain a mathematical model with fluorescence intensity as a structure variable to describe the evolution in time of proliferating cells labeled by carboxyfluorescein succinimidyl ester (CFSE). Here, this model and several extensions/modifications are discussed. Suggestions for improvements are presented and analyzed with respect to statistical significance for better agreement between model solutions and experimental data. These investigations suggest that the new decay/label loss and time dependent effective proliferation and death rates do indeed provide improved fits of the model to data. Statistical models for the observed variability/noise in the data are discussed with implications for uncertainty quantification. The resulting new cell dynamics model should prove useful in proliferation assay tracking and modeling, with numerous applications in the biomedical sciences. PMID:20195910

  6. Suppression of vascular smooth muscle cells' proliferation and ...

    African Journals Online (AJOL)

    This study aimed to determine the effects of valsartan on the proliferation and migration of isolated rat vascular smooth muscle cells (VSMCs) and the expression of phospho-p42/44 mitogen-activated protein kinase (MAPK) promoted by angiotensin II (Ang II). VSMCs from the rat thoracic aorta were cultured by ...

  7. Effect of Ultrasonic Vibration on Proliferation and Differentiation of Cells

    Directory of Open Access Journals (Sweden)

    Haruka Hino

    2016-12-01

    Full Text Available The effect of mechanical stimulation of vibration on proliferation and differentiation of cells has been studied in vitro. To apply the vibration on the cells, a piezoelectric element was attached on the outside surface of the bottom of the culture plate of six wells. The piezoelectric element was vibrated by sinusoidally alternating voltage at 1.0 MHz generated by a function generator. Five kinds of cells were used in the experiment: C2C12 (mouse myoblast cell, L929 (fibroblast connective tissue of mouse, Hepa1-6 (mouse hepatoma cell, HUVEC (human umbilical vein endothelial cell, and Neuro-2a (mouse neural crest-derived cell line. After the incubation for 24 hours, cells were exposed to the ultrasonic vibration intermittently for three days: for thirty minutes per day. At the end of the experiment, the number of cells was counted by colorimetric method with a microplate photometer. In the case of Neuro-2a, the total length of the neurite was calculated at the microscopic image. The experimental study shows following results. Cells are exfoliated by the strong vibration. Proliferation and differentiation of cells are accelerated with mild vibration. The optimum intensity of vibration depends on the kind of cells.

  8. Long Noncoding RNA PANDA Positively Regulates Proliferation of Osteosarcoma Cells.

    Science.gov (United States)

    Kotake, Yojiro; Goto, Taiki; Naemura, Madoka; Inoue, Yasutoshi; Okamoto, Haruna; Tahara, Keiichiro

    2017-01-01

    A long noncoding RNA, p21-associated ncRNA DNA damage-activated (PANDA), associates with nuclear transcription factor Y subunit alpha (NF-YA) and inhibits its binding to promoters of apoptosis-related genes, thereby repressing apoptosis in normal human fibroblasts. Here, we show that PANDA is involved in regulating proliferation in the U2OS human osteosarcoma cell line. U2OS cells were transfected with siRNAs against PANDA 72 h later and they were subjected to reverse transcription-polymerase chain reaction (RT-PCR), quantitative RT-PCR and cell-cycle analysis. PANDA was highly expressed in U2OS cells, and its expression was induced by DNA damage. Silencing PANDA caused arrest at the G 1 phase of the cell cycle, leading to inhibition of cell proliferation. Quantitative RT-PCR showed that silencing PANDA increased mRNA levels of the cyclin-dependent kinase inhibitor p18, which caused G 1 phase arrest. These results suggest that PANDA promotes G 1 -S transition by repressing p18 transcription, and thus promotes U2OS cell proliferation. Copyright© 2017 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  9. A Neural Network Based Workstation for Automated Cell Proliferation Analysis

    Science.gov (United States)

    2001-10-25

    work was supported by the Programa de Apoyo a Proyectos de Desarrollo e Investigacíon en Informática REDII 2000. We thank Blanca Itzel Taboada for...Meléndez1, G. Corkidi.2 1Centro de Instrumentos, UNAM. P.O. Box 70-186, México 04510, D.F. 2Instituto de Biotecnología, UNAM. P.O. Box 510-3, 62250...proliferation analysis, of cytological microscope images. The software of the system assists the expert biotechnologist during cell proliferation and

  10. Noninvasive Assessment of Tumor Cell Proliferation in Animal Models

    Directory of Open Access Journals (Sweden)

    Matthias Edinger

    1999-10-01

    Full Text Available Revealing the mechanisms of neoplastic disease and enhancing our ability to intervene in these processes requires an increased understanding of cellular and molecular changes as they occur in intact living animal models. We have begun to address these needs by developing a method of labeling tumor cells through constitutive expression of an optical reporter gene, noninvasively monitoring cellular proliferation in vivo using a sensitive photon detection system. A stable line of HeLa cells that expressed a modified firefly luciferase gene was generated, proliferation of these cells in irradiated severe combined immunodeficiency (SCID mice was monitored. Tumor cells were introduced into animals via subcutaneous, intraperitoneal and intravenous inoculation and whole body images, that revealed tumor location and growth kinetics, were obtained. The number of photons that were emitted from the labeled tumor cells and transmitted through murine tissues was sufficient to detect 1×103 cells in the peritoneal cavity, 1×104 cells at subcutaneous sites and 1×106 circulating cells immediately following injection. The kinetics of cell proliferation, as measured by photon emission, was exponential in the peritoneal cavity and at subcutaneous sites. Intravenous inoculation resulted in detectable colonies of tumor cells in animals receiving more than 1×103 cells. Our demonstrated ability to detect small numbers of tumor cells in living animals noninvasively suggests that therapies designed to treat minimal disease states, as occur early in the disease course and after elimination of the tumor mass, may be monitored using this approach. Moreover, it may be possible to monitor micrometastases and evaluate the molecular steps in the metastatic process. Spatiotemporal analyses of neoplasia will improve the predictability of animal models of human disease as study groups can be followed over time, this method will accelerate development of novel therapeutic

  11. Hematopoietic stem cell migration and proliferation after Partial body irradiation

    International Nuclear Information System (INIS)

    Murata, Takashi; Utsumi, Makoto; Hotta, Tomomitsu; Yamada, Hideo

    1983-01-01

    Stem cell migration in hematopoietic recovery after partial body irradiation was investigated with special emphasis on the comparative roles of the bone marrow and the spleen. The number of CFU-S in circulation declined rapidly and reached zero within a day after irradiation, thereafter it increased gradually. This finding suggests the presence of two different phases of stem cell migration. One is a rapid migrating phase in which stem cells are released rapidly within a day after irradiation, and the other is a slow migrating phase. The result of split doses of local body irradiation experiments implicated a role for the spleen distinct from that of the bone marrow in the preferential distribution of stem cells early after irradiation. The cell kinetic study showed that the proliferation of CFU-S occurred actively in irradiated bone marrow and the spleens as compared to that in unirradiated control. But on Day 7 and on Day 10 after irradiation, the proliferation of CFU-S in shielded bone marrow did not occur as actively as those in irradiated areas. The results of our present studies suggest that the spleen is not only the storage pools of migrating stem cells but also the main site of active proliferation of CFU-S in the early period of hematopoietic regeneration. (author)

  12. Downregulation of an Aim-1 Kinase Couples with Megakaryocytic Polyploidization of Human Hematopoietic Cells

    Science.gov (United States)

    Kawasaki, Akira; Matsumura, Itaru; Miyagawa, Jun-ichiro; Ezoe, Sachiko; Tanaka, Hirokazu; Terada, Yasuhiko; Tatsuka, Masaaki; Machii, Takashi; Miyazaki, Hiroshi; Furukawa, Yusuke; Kanakura, Yuzuru

    2001-01-01

    During the late phase of megakaryopoiesis, megakaryocytes undergo polyploidization, which is characterized by DNA duplication without concomitant cell division. However, it remains unknown by which mechanisms this process occurs. AIM-1 and STK15 belong to the Aurora/increase-in-ploidy (Ipl)1 serine/threonine kinase family and play key roles in mitosis. In a human interleukin-3–dependent cell line, F-36P, the expressions of AIM-1 and STK15 mRNA were specifically observed at G2/M phase of the cell cycle during proliferation. In contrast, the expressions of AIM-1 and STK15 were continuously repressed during megakaryocytic polyploidization of human erythro/megakaryocytic cell lines (F-36P, K562, and CMK) treated with thrombopoietin, activated ras (H-rasG12V), or phorbol ester. Furthermore, their expressions were suppressed during thrombopoietin-induced polyploidization of normal human megakaryocytes. Activation of AIM-1 by the induced expression of AIM-1(wild-type) canceled TPA-induced polyploidization of K562 cells significantly, whereas that of STK15 did not. Moreover, suppression of AIM-1 by the induced expression of AIM-1 (K/R, dominant-negative type) led to polyploidization in 25% of K562 cells, whereas STK15(K/R) showed no effect. Also, the induced expression of AIM-1(K/R) in CMK cells provoked polyploidization up to 32N. These results suggested that downregulation of AIM-1 at M phase may be involved in abortive mitosis and polyploid formation of megakaryocytes. PMID:11266445

  13. [Regulation of airway stem cell proliferation in idiopathic pulmonary fibrosis].

    Science.gov (United States)

    Yang, S X; Wu, Q; Sun, X; Li, X; Li, K; Xu, L; Li, Y; Zhang, Q Y; Zhang, Y C; Chen, H Y

    2016-09-01

    To investigate the effect of fibroblasts on regulating airway stem cell proliferation in idiopathic pulmonary fibrosis. Lung cell suspension was prepared from β-actin-GFP mice. Airway stem cells were obtained by fluorescence activated cell sorting and co-cultured with lung fibroblasts. The fibroblasts were treated with TGF-β inhibitor SB43142. The expression of growth factors FGF1/2 and the effect of FGF1/2 on stem cell proliferation were observed. The cloning efficiency of airway stem cells, when co-cultured with normal lung fibroblast cells for 8 days, was (3.5±1.1)%, while the cloning efficiency was reduced to (0.04±0.04)% when co-cultured with lung fibroblasts from idiopathic pulmonary fibrosis patients. The difference between the 2 groups was statistically significant(P=0.002 5). TGF-β receptor inhibitor SB431542 increased lung fibroblast growth factors FGF1/2 expression.FGF1 mRNA expression was increased to the experimental group 0.005 5 from 0.000 2 in the control group.FGF2 mRNA expression of the amount raised to the experimental group 0.000 15 from 0.000 8 in the control group.FGF1/2 promoted the growth of airway stem cells. After FGF1/2 was co-cultured with normal lung fibroblast cells for 8 days, the cloning efficiency of airway stem cells was (0.3±0.1)%. During the development of idiopathic pulmonary fibrosis, fibroblast secreted FGF1/2 regulate airway stem cell proliferation.

  14. RNA interference targeting raptor inhibits proliferation of gastric cancer cells

    International Nuclear Information System (INIS)

    Wu, William Ka Kei; Lee, Chung Wa; Cho, Chi Hin; Chan, Francis Ka Leung; Yu, Jun; Sung, Joseph Jao Yiu

    2011-01-01

    Mammalian target of rapamycin complex 1 (mTORC1) is dysregulated in gastric cancer. The biologic function of mTORC1 in gastric carcinogenesis is unclear. Here, we demonstrate that disruption of mTORC1 function by RNA interference-mediated downregulation of raptor substantially inhibited gastric cancer cell proliferation through induction of G 0 /G 1 -phase cell cycle arrest. The anti-proliferative effect was accompanied by concomitant downregulation of activator protein-1 and upregulation of Smad2/3 transcriptional activities. In addition, the expression of cyclin D 3 and p21 Waf1 , which stabilizes cyclin D/cdk4 complex for G 1 -S transition, was reduced by raptor knockdown. In conclusion, disruption of mTORC1 inhibits gastric cancer cell proliferation through multiple pathways. This discovery may have an implication in the application of mTORC1-directed therapy for the treatment of gastric cancer.

  15. ERβ inhibits proliferation and invasion of breast cancer cells

    Science.gov (United States)

    Lazennec, Gwendal; Bresson, Damien; Lucas, Annick; Chauveau, Corine; Vignon, Françoise

    2001-01-01

    Recent studies indicate that the expression of ERβ in breast cancer is lower than in normal breast, suggesting that ERβ could play an important role in carcinogenesis. To investigate this hypothesis, we engineered estrogen-receptor negative MDA-MB-231 breast cancer cells to reintroduce either ERα or ERβ protein with an adenoviral vector. In these cells, ERβ (as ERα) expression was monitored using RT-PCR and Western blot. ERβ protein was localized in the nucleus (immunocytochemistry) and able to transactivate estrogen-responsive reporter constructs in the presence of estradiol. ERβ and ERα induced the expression of several endogenous genes such as pS2, TGFα or the cyclin kinase inhibitor p21, but in contrast to ERα, ERβ was unable to regulate c-myc proto-oncogene expression. The pure antiestrogen ICI 164, 384 completely blocked ERα and ERβ estrogen-induced activities. ERβ inhibited MDA-MB-231 cell proliferation in a ligand-independent manner, whereas ERα inhibition of proliferation is hormone-dependent. Moreover, ERβ and ERα, decreased cell motility and invasion. Our data bring the first evidence that ERβ is an important modulator of proliferation and invasion of breast cancer cells and support the hypothesis that the loss of ERβ expression could be one of the events leading to the development of breast cancer. PMID:11517191

  16. Proliferation of Schwann cells induced by axolemmal and myelin membranes

    International Nuclear Information System (INIS)

    Dinneen, M.

    1985-01-01

    Purified Schwann Cells were cultured from neonatal rat sciatic nerve using a modification of the method of Brockes. Schwann cells and contaminating fibroblasts were unambiguously identified using fluorescent antibodies of 2'3' cyclic nucleotide 3'-phosphodiesterase and the thy 1.1 antigen respectively. The Schwann cells were quiescent unless challenged with mitogens. They proliferated rapidly in response to the soluble mitogen, cholera toxin, or to membrane fractions from rat CNS or PNS, prepared by the method of DeVries. Mitogenic activity was present in both axolemmal and myelin enriched fractions and promoted a 10-15 fold increase in the rate of 3 H-thymidine uptake. The axolemmal mitogen was sensitive to heat (80 0 C for 10 minutes), trypsin digestion (0.05% x 30 mins) or to treatment with endoglycosidase D, suggesting that it could be a glycoprotein. Fifty percent of the axolemmal mitogenic activity was solubilized in 1% octyl-glucoside. The solubilized material, however, was very unstable and further purification was not possible. The myelin associated mitogenic activity was markedly different. It was resistant to freeze thaw cycles, trypsin digestion of endoglycosidase treatment and the activity was actually enhanced by heating at 100 0 C for two hours. It is proposed that the axolemmal activity is responsible for Schwann cell proliferation during development and that the myelin associated activity promotes Schwann cell proliferation during Wallerian degeneration

  17. Stimulation and support of haemopoietic stem cell proliferation by irradiated stroma cell colonies in bone marrow cell culture in vitro

    International Nuclear Information System (INIS)

    Mori, K.J.; Izumi, Hiroko; Seto, Akira

    1981-01-01

    A culture system was established in which haemopoietic stem cells can undergo a recovery proliferation after a depletion of the stem cells, completely in vitro. To elucidate the source of the stimulatory factors, normal bone marrow cells were overlayed on top of the irradiated adherent 'stromal' cell colonies in the bone marrow cell culture. This stimulated the proliferation of haemopoietic stem cells in the cultured cells in suspension. The present results indicate that the stromal cells produce factors which stimulate stem cell proliferation. Whether the stimulation is evoked by direct cell-cell interactions or by humoral factors is as yet to be studied. (author)

  18. Nifedipine promotes the proliferation and migration of breast cancer cells.

    Directory of Open Access Journals (Sweden)

    Dong-Qing Guo

    Full Text Available Nifedipine is widely used as a calcium channel blocker (CCB to treat angina and hypertension,but it is controversial with respect the risk of stimulation of cancers. In this study, we demonstrated that nifedipine promoted the proliferation and migration of breast cancer cells both invivo and invitro. However, verapamil, another calcium channel blocker, didn't exert the similar effects. Nifedipine and high concentration KCl failed to alter the [Ca2+]i in MDA-MB-231 cells, suggesting that such nifedipine effect was not related with calcium channel. Moreover, nifedipine decreased miRNA-524-5p, resulting in the up-regulation of brain protein I3 (BRI3. Erk pathway was consequently activated and led to the proliferation and migration of breast cancer cells. Silencing BRI3 reversed the promoting effect of nifedipine on the breast cancer. In a summary, nifedipine stimulated the proliferation and migration of breast cancer cells via the axis of miRNA-524-5p-BRI3-Erk pathway independently of its calcium channel-blocking activity. Our findings highlight that nifedipine but not verapamil is conducive for breast cancer growth and metastasis, urging that the caution should be taken in clinic to prescribe nifedipine to women who suffering both hypertension and breast cancer, and hypertension with a tendency in breast cancers.

  19. Effects of electrical stimulation on cell proliferation and apoptosis.

    Science.gov (United States)

    Love, Maria R; Palee, Siripong; Chattipakorn, Siriporn C; Chattipakorn, Nipon

    2018-03-01

    The application of exogenous electrical stimulation (ES) to cells in order to manipulate cell apoptosis and proliferation has been widely investigated as a possible method of treatment in a number of diseases. Alteration of the transmembrane potential of cells via ES can affect various intracellular signaling pathways which are involved in the regulation of cellular function. Controversially, several types of ES have proved to be effective in both inhibiting or inducing apoptosis, as well as increasing proliferation. However, the mechanisms through which ES achieves this remain fairly unclear. The aim of this review was to comprehensively summarize current findings from in vitro and in vivo studies on the effects of different types of ES on cell apoptosis and proliferation, highlighting the possible mechanisms through which ES induced these effects and define the optimum parameters at which ES can be used. Through this we hope to provide a greater insight into how future studies can most effectively use ES at the clinical trial stage. © 2017 Wiley Periodicals, Inc.

  20. Angiotensin Converting Enzyme Regulates Cell Proliferation and Migration.

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    Erika Costa de Alvarenga

    Full Text Available The angiotensin-I converting enzyme (ACE plays a central role in the renin-angiotensin system, acting by converting the hormone angiotensin-I to the active peptide angiotensin-II (Ang-II. More recently, ACE was shown to act as a receptor for Ang-II, and its expression level was demonstrated to be higher in melanoma cells compared to their normal counterparts. However, the function that ACE plays as an Ang-II receptor in melanoma cells has not been defined yet.Therefore, our aim was to examine the role of ACE in tumor cell proliferation and migration.We found that upon binding to ACE, Ang-II internalizes with a faster onset compared to the binding of Ang-II to its classical AT1 receptor. We also found that the complex Ang-II/ACE translocates to the nucleus, through a clathrin-mediated process, triggering a transient nuclear Ca2+ signal. In silico studies revealed a possible interaction site between ACE and phospholipase C (PLC, and experimental results in CHO cells, demonstrated that the β3 isoform of PLC is the one involved in the Ca2+ signals induced by Ang-II/ACE interaction. Further studies in melanoma cells (TM-5 showed that Ang-II induced cell proliferation through ACE activation, an event that could be inhibited either by ACE inhibitor (Lisinopril or by the silencing of ACE. In addition, we found that stimulation of ACE by Ang-II caused the melanoma cells to migrate, at least in part due to decreased vinculin expression, a focal adhesion structural protein.ACE activation regulates melanoma cell proliferation and migration.

  1. XIAP antagonist embelin inhibited proliferation of cholangiocarcinoma cells.

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    Cody J Wehrkamp

    Full Text Available Cholangiocarcinoma cells are dependent on antiapoptotic signaling for survival and resistance to death stimuli. Recent mechanistic studies have revealed that increased cellular expression of the E3 ubiquitin-protein ligase X-linked inhibitor of apoptosis (XIAP impairs TRAIL- and chemotherapy-induced cytotoxicity, promoting survival of cholangiocarcinoma cells. This study was undertaken to determine if pharmacologic antagonism of XIAP protein was sufficient to sensitize cholangiocarcinoma cells to cell death. We employed malignant cholangiocarcinoma cell lines and used embelin to antagonize XIAP protein. Embelin treatment resulted in decreased XIAP protein levels by 8 hours of treatment with maximal effect at 16 hours in KMCH and Mz-ChA-1 cells. Assessment of nuclear morphology demonstrated a concentration-dependent increase in nuclear staining. Interestingly, embelin induced nuclear morphology changes as a single agent, independent of the addition of TNF-related apoptosis inducing ligand (TRAIL. However, caspase activity assays revealed that increasing embelin concentrations resulted in slight inhibition of caspase activity, not activation. In addition, the use of a pan-caspase inhibitor did not prevent nuclear morphology changes. Finally, embelin treatment of cholangiocarcinoma cells did not induce DNA fragmentation or PARP cleavage. Apoptosis does not appear to contribute to the effects of embelin on cholangiocarcinoma cells. Instead, embelin caused inhibition of cell proliferation and cell cycle analysis indicated that embelin increased the number of cells in S and G2/M phase. Our results demonstrate that embelin decreased proliferation in cholangiocarcinoma cell lines. Embelin treatment resulted in decreased XIAP protein expression, but did not induce or enhance apoptosis. Thus, in cholangiocarcinoma cells the mechanism of action of embelin may not be dependent on apoptosis.

  2. URG11 Regulates Prostate Cancer Cell Proliferation, Migration, and Invasion

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    Bin Pan

    2018-01-01

    Full Text Available Upregulated gene 11 (URG11, a new gene upregulated by hepatitis B virus X protein, is involved in the development and progression of several tumors, including liver, stomach, lung, and colon cancers. However, the role of URG11 in prostate cancer remains yet to be elucidated. By determined expression in human prostate cancer tissues, URG11 was found significantly upregulated and positively correlated with the severity of prostate cancer, compared with that in benign prostatic hyperplasia tissues. Further, the mRNA and protein levels of URG11 were significantly upregulated in human prostate cancer cell lines (DU145, PC3, and LNCaP, compared with human prostate epithelial cell line (RWPE-1. Moreover, by the application of siRNA against URG11, the proliferation, migration, and invasion of prostate cancer cells were markedly inhibited. Genetic knockdown of URG11 also induced cell cycle arrest at G1/S phase, induced apoptosis, and decreased the expression level of β-catenin in prostate cancer cells. Overexpression of URG11 promoted the expression of β-catenin, the growth, the migration, and invasion ability of prostate cancer cells. Taken together, this study reveals that URG11 is critical for the proliferation, migration, and invasion in prostate cancer cells, providing the evidence of URG11 to be a novel potential therapeutic target of prostate cancer.

  3. Albumin Suppresses Human Hepatocellular Carcinoma Proliferation and the Cell Cycle

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    Shunsuke Nojiri

    2014-03-01

    Full Text Available Many investigations have revealed that a low recurrence rate of hepatocellular carcinoma (HCC is associated with high serum albumin levels in patients; therefore, high levels of serum albumin are a major indicator of a favorable prognosis. However, the mechanism inhibiting the proliferation of HCC has not yet been elucidated, so we investigated the effect of serum albumin on HCC cell proliferation. Hep3B was cultured in MEM with no serum or containing 5 g/dL human albumin. As control samples, Prionex was added to generate the same osmotic pressure as albumin. After 24-h incubation, the expressions of α-fetoprotein (AFP, p53, p21, and p57 were evaluated with real-time PCR using total RNA extracted from the liver. Protein expressions and the phosphorylation of Rb (retinoblastoma were determined by Western blot analysis using total protein extracted from the liver. For flow cytometric analysis of the cell cycle, FACS analysis was performed. The percentages of cell cycle distribution were evaluated by PI staining, and all samples were analyzed employing FACScalibur (BD with appropriate software (ModFit LT; BD. The cell proliferation assay was performed by counting cells with using a Scepter handy automated cell counter (Millipore. The mRNA levels of AFP relative to Alb(−: Alb(−, Alb(+, and Prionex, were 1, 0.7 ± 0.2 (p < 0.001 for Alb(−, and 1 ± 0.3, respectively. The mRNA levels of p21 were 1, 1.58 ± 0.4 (p = 0.007 for Alb(− and p = 0.004 for Prionex, and 0.8 ± 0.2, respectively. The mRNA levels of p57 were 1, 4.4 ± 1.4 (p = 0.002 for Alb(− and Prionex, and 1.0 ± 0.1, respectively. The protein expression levels of Rb were similar in all culture media. The phosphorylation of P807/811 and P780 of Rb protein was reduced in Alb(+. More cells in the G0/G1 phase and fewer cells in S and G2/M phases were obtained in Alb(+ than in Alb(− (G0/G1: 60.9%, 67.7%, 61.5%; G2/M: 16.5%, 13.1%, 15.6%; S: 22.6%, 19.2%, 23.0%, Alb(−, Alb

  4. Nuclear orphan receptor TLX affects gene expression, proliferation and cell apoptosis in beta cells

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Xiaoli; Xiong, Xiaokan; Dai, Zhe; Deng, Haohua; Sun, Li; Hu, Xuemei; Zhou, Feng; Xu, Yancheng, E-mail: oxyccc@163.com

    2015-12-04

    Nuclear orphan receptor TLX is an essential regulator of the growth of neural stem cells. However, its exact function in pancreatic islet cells is still unknown. In the present study, gene expression profiling analysis revealed that overexpression of TLX in beta cell line MIN6 causes suppression of 176 genes and upregulation of 49 genes, including a cadre of cell cycle, cell proliferation and cell death control genes, such as Btg2, Ddit3 and Gadd45a. We next examined the effects of TLX overexpression on proliferation, apoptosis and insulin secretion in MIN6 cells. Proliferation analysis using EdU assay showed that overexpression of TLX increased percentage of EdU-positive cells. Cell cycle and apoptosis analysis revealed that overexpression of TLX in MIN6 cells resulted in higher percentage of cells exiting G1 into S-phase, and a 58.8% decrease of cell apoptosis induced by 0.5 mM palmitate. Moreover, TLX overexpression did not cause impairment of insulin secretion. Together, we conclude that TLX is among factors capable of controlling beta cell proliferation and survival, which may serve as a target for the development of novel therapies for diabetes. - Highlights: • TLX overexpression in MIN6 cell causes significant expression changes of 225 genes. • TLX overexpression promotes MIN6 cell proliferation and decreases cell apoptosis. • TLX overexpression does not cause impairment of insulin secretion.

  5. Nuclear orphan receptor TLX affects gene expression, proliferation and cell apoptosis in beta cells

    International Nuclear Information System (INIS)

    Shi, Xiaoli; Xiong, Xiaokan; Dai, Zhe; Deng, Haohua; Sun, Li; Hu, Xuemei; Zhou, Feng; Xu, Yancheng

    2015-01-01

    Nuclear orphan receptor TLX is an essential regulator of the growth of neural stem cells. However, its exact function in pancreatic islet cells is still unknown. In the present study, gene expression profiling analysis revealed that overexpression of TLX in beta cell line MIN6 causes suppression of 176 genes and upregulation of 49 genes, including a cadre of cell cycle, cell proliferation and cell death control genes, such as Btg2, Ddit3 and Gadd45a. We next examined the effects of TLX overexpression on proliferation, apoptosis and insulin secretion in MIN6 cells. Proliferation analysis using EdU assay showed that overexpression of TLX increased percentage of EdU-positive cells. Cell cycle and apoptosis analysis revealed that overexpression of TLX in MIN6 cells resulted in higher percentage of cells exiting G1 into S-phase, and a 58.8% decrease of cell apoptosis induced by 0.5 mM palmitate. Moreover, TLX overexpression did not cause impairment of insulin secretion. Together, we conclude that TLX is among factors capable of controlling beta cell proliferation and survival, which may serve as a target for the development of novel therapies for diabetes. - Highlights: • TLX overexpression in MIN6 cell causes significant expression changes of 225 genes. • TLX overexpression promotes MIN6 cell proliferation and decreases cell apoptosis. • TLX overexpression does not cause impairment of insulin secretion.

  6. Cell adhesion and proliferation on polyethylene grafted with Au nanoparticles

    Czech Academy of Sciences Publication Activity Database

    Kasálková-Slepičková, N.; Slepička, P.; Kolská, Z.; Sajdl, P.; Bačáková, Lucie; Rimpelová, S.; Švorčík, V.

    2012-01-01

    Roč. 272, FEB 1 (2012), s. 391-395 ISSN 0168-583X. [International Conference on Ion Beam Modification of Materials /17./. Montreal, 22.08.2010-27.08.2010] R&D Projects: GA ČR(CZ) GAP108/10/1106; GA AV ČR(CZ) KAN400480701 Institutional research plan: CEZ:AV0Z50110509 Keywords : polyenthyne * gold nanoparticles * grafting * cell proliferation Subject RIV: EI - Biotechnology ; Bionics Impact factor: 1.266, year: 2012

  7. Co-culture with Sertoli cells promotes proliferation and migration of umbilical cord mesenchymal stem cells

    International Nuclear Information System (INIS)

    Zhang, Fenxi; Hong, Yan; Liang, Wenmei; Ren, Tongming; Jing, Suhua; Lin, Juntang

    2012-01-01

    Highlights: ► Co-culture of Sertoli cells (SCs) with human umbilical cord mesenchymal stem cells (UCMSCs). ► Presence of SCs dramatically increased proliferation and migration of UCMSCs. ► Presence of SCs stimulated expression of Mdm2, Akt, CDC2, Cyclin D, CXCR4, MAPKs. -- Abstract: Human umbilical cord mesenchymal stem cells (hUCMSCs) have been recently used in transplant therapy. The proliferation and migration of MSCs are the determinants of the efficiency of MSC transplant therapy. Sertoli cells are a kind of “nurse” cells that support the development of sperm cells. Recent studies show that Sertoli cells promote proliferation of endothelial cells and neural stem cells in co-culture. We hypothesized that co-culture of UCMSCs with Sertoli cells may also promote proliferation and migration of UCMSCs. To examine this hypothesis, we isolated UCMSCs from human cords and Sertoli cells from mouse testes, and co-cultured them using a Transwell system. We found that UCMSCs exhibited strong proliferation ability and potential to differentiate to other cell lineages such as osteocytes and adipocytes. The presence of Sertoli cells in co-culture significantly enhanced the proliferation and migration potential of UCMSCs (P < 0.01). Moreover, these phenotypic changes were accompanied with upregulation of multiple genes involved in cell proliferation and migration including phospho-Akt, Mdm2, phospho-CDC2, Cyclin D1, Cyclin D3 as well as CXCR4, phospho-p44 MAPK and phospho-p38 MAPK. These findings indicate that Sertoli cells boost UCMSC proliferation and migration potential.

  8. Co-culture with Sertoli cells promotes proliferation and migration of umbilical cord mesenchymal stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Fenxi, E-mail: fxzhang0824@gmail.com [Department of Anatomy, Sanquan College, Xinxiang Medical University, Henan 453003, People' s Republic of China (China); Hong, Yan; Liang, Wenmei [Department of Histology and Embryology, Guiyang Medical University, Guizhou 550004, People' s Republic of China (China); Ren, Tongming [Department of Anatomy, Sanquan College, Xinxiang Medical University, Henan 453003, People' s Republic of China (China); Jing, Suhua [ICU Center, The Third Hospital of Xinxiang Medical University, Henan 453003, People' s Republic of China (China); Lin, Juntang [Stem Cell Center, Xinxiang Medical University, Henan 453003, People' s Republic of China (China)

    2012-10-12

    Highlights: Black-Right-Pointing-Pointer Co-culture of Sertoli cells (SCs) with human umbilical cord mesenchymal stem cells (UCMSCs). Black-Right-Pointing-Pointer Presence of SCs dramatically increased proliferation and migration of UCMSCs. Black-Right-Pointing-Pointer Presence of SCs stimulated expression of Mdm2, Akt, CDC2, Cyclin D, CXCR4, MAPKs. -- Abstract: Human umbilical cord mesenchymal stem cells (hUCMSCs) have been recently used in transplant therapy. The proliferation and migration of MSCs are the determinants of the efficiency of MSC transplant therapy. Sertoli cells are a kind of 'nurse' cells that support the development of sperm cells. Recent studies show that Sertoli cells promote proliferation of endothelial cells and neural stem cells in co-culture. We hypothesized that co-culture of UCMSCs with Sertoli cells may also promote proliferation and migration of UCMSCs. To examine this hypothesis, we isolated UCMSCs from human cords and Sertoli cells from mouse testes, and co-cultured them using a Transwell system. We found that UCMSCs exhibited strong proliferation ability and potential to differentiate to other cell lineages such as osteocytes and adipocytes. The presence of Sertoli cells in co-culture significantly enhanced the proliferation and migration potential of UCMSCs (P < 0.01). Moreover, these phenotypic changes were accompanied with upregulation of multiple genes involved in cell proliferation and migration including phospho-Akt, Mdm2, phospho-CDC2, Cyclin D1, Cyclin D3 as well as CXCR4, phospho-p44 MAPK and phospho-p38 MAPK. These findings indicate that Sertoli cells boost UCMSC proliferation and migration potential.

  9. Dendritic cells modulate burn wound healing by enhancing early proliferation.

    Science.gov (United States)

    Vinish, Monika; Cui, Weihua; Stafford, Eboni; Bae, Leon; Hawkins, Hal; Cox, Robert; Toliver-Kinsky, Tracy

    2016-01-01

    Adequate wound healing is vital for burn patients to reduce the risk of infections and prolonged hospitalization. Dendritic cells (DCs) are antigen presenting cells that release cytokines and are central for the activation of innate and acquired immune responses. Studies have showed their presence in human burn wounds; however, their role in burn wound healing remains to be determined. This study investigated the role of DCs in modulating healing responses within the burn wound. A murine model of full-thickness contact burns was used to study wound healing in the absence of DCs (CD11c promoter-driven diphtheria toxin receptor transgenic mice) and in a DC-rich environment (using fms-like tyrosine kinase-3 ligand, FL- a DC growth factor). Wound closure was significantly delayed in DC-deficient mice and was associated with significant suppression of early cellular proliferation, granulation tissue formation, wound levels of TGFβ1 and formation of CD31+ vessels in healing wounds. In contrast, DC enhancement significantly accelerated early wound closure, associated with increased and accelerated cellular proliferation, granulation tissue formation, and increased TGFβ1 levels and CD31+ vessels in healing wounds. We conclude that DCs play an important role in the acceleration of early wound healing events, likely by secreting factors that trigger the proliferation of cells that mediate wound healing. Therefore, pharmacological enhancement of DCs may provide a therapeutic intervention to facilitate healing of burn wounds. © 2016 by the Wound Healing Society.

  10. Niclosamide suppresses hepatoma cell proliferation via the Wnt pathway

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    Tomizawa M

    2013-11-01

    Full Text Available Minoru Tomizawa,1 Fuminobu Shinozaki,2 Yasufumi Motoyoshi,3 Takao Sugiyama,4 Shigenori Yamamoto,5 Makoto Sueishi,4 Takanobu Yoshida6 1Department of Gastroenterology, 2Department of Radiology, 3Department of Neurology, 4Department of Rheumatology, 5Department of Pediatrics, 6Department of Internal Medicine, National Hospital Organization Shimoshizu Hospital, Yotsukaido City, Chiba, Japan Background: The Wnt pathway plays an important role in hepatocarcinogenesis. We analyzed the association of the Wnt pathway with the proliferation of hepatoma cells using Wnt3a and niclosamide, a drug used to treat tapeworm infection. Methods: We performed an MTS assay to determine whether Wnt3a stimulated proliferation of Huh-6 and Hep3B human hepatoma cell lines after 72 hours of incubation with Wnt3a in serum-free medium. The cells were subjected to hematoxylin and eosin staining and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL after 48 hours of incubation. RNA was isolated 48 hours after addition of Wnt3a or niclosamide, and cyclin D1 expression levels were analyzed by real-time quantitative polymerase chain reaction. The promoter activity of T-cell factor was analyzed by luciferase assay 48 hours after transfection of TOPflash. Western blot analysis was performed with antibodies against β-catenin, dishevelled 2, and cyclin D1. Results: Cell proliferation increased with Wnt3a. Niclosamide suppressed proliferation with or without Wnt3a. Hematoxylin and eosin and TUNEL staining suggested that apoptosis occurred in cells with niclosamide. Cyclin D1 was upregulated in the presence of Wnt3a and downregulated with addition of niclosamide. The promoter activity of T-cell factor increased with Wnt3a, whereas T-cell factor promoter activity decreased with niclosamide. Western blot analysis showed that Wnt3a upregulated β-catenin, dishevelled 2, and cyclin D1, while niclosamide downregulated them. Conclusion: Niclosamide is a potential

  11. Transient fluctuations of intracellular zinc ions in cell proliferation

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    Li, Yuan [Division of Human Nutrition, Department of Preventive Medicine and Community Health, The University of Texas Medical Branch, Galveston, TX 77555 (United States); Maret, Wolfgang, E-mail: womaret@utmb.edu [Division of Human Nutrition, Department of Preventive Medicine and Community Health, The University of Texas Medical Branch, Galveston, TX 77555 (United States); Department of Anesthesiology, The University of Texas Medical Branch, Galveston, TX 77555 (United States)

    2009-08-15

    Zinc is essential for cell proliferation, differentiation, and viability. When zinc becomes limited for cultured cells, DNA synthesis ceases and the cell cycle is arrested. The molecular mechanisms of actions of zinc are believed to involve changes in the availability of zinc(II) ions (Zn{sup 2+}). By employing a fluorescent Zn{sup 2+} probe, FluoZin-3 acetoxymethyl ester, intracellular Zn{sup 2+} concentrations were measured in undifferentiated and in nerve growth factor (NGF)-differentiated rat pheochromocytoma (PC12) cells. Intracellular Zn{sup 2+} concentrations are pico- to nanomolar in PC12 cells and are higher in the differentiated than in the undifferentiated cells. When following cellular Zn{sup 2+} concentrations for 48 h after the removal of serum, a condition that is known to cause cell cycle arrest, Zn{sup 2+} concentrations decrease after 30 min but, remarkably, increase after 1 h, and then decrease again to about one half of the initial concentration. Cell proliferation, measured by an MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay, decreases after both serum starvation and zinc chelation. Two peaks of Zn{sup 2+} concentrations occur within one cell cycle: one early in the G1 phase and the other in the late G1/S phase. Thus, fluctuations of intracellular Zn{sup 2+} concentrations and established modulation of phosphorylation signaling, via an inhibition of protein tyrosine phosphatases at commensurately low Zn{sup 2+} concentrations, suggest a role for Zn{sup 2+} in the control of the cell cycle. Interventions targeted at these picomolar Zn{sup 2+} fluctuations may be a way of controlling cell growth in hyperplasia, neoplasia, and diseases associated with aberrant differentiation.

  12. Mobile phone radiation alters proliferation of hepatocarcinoma cells.

    Science.gov (United States)

    Ozgur, Elcin; Guler, Goknur; Kismali, Gorkem; Seyhan, Nesrin

    2014-11-01

    This study investigated the effects of intermittent exposure (15 min on, 15 min off for 1, 2, 3, or 4 h, at a specific absorption rate of 2 W/kg) to enhanced data rates for global system for mobile communication evolution-modulated radiofrequency radiation (RFR) at 900- and 1,800-MHz frequencies on the viability of the Hepatocarcinoma cells (Hep G2). Hep G2 cell proliferation was measured by a colorimetric assay based on the cleavage of the tetrazolium salt WST-1 by mitochondrial dehydrogenases in viable cells. Cell injury was evaluated by analyzing the levels of lactate dehydrogenase (LDH) and glucose released from lysed cells into the culture medium. Morphological observation of the nuclei was carried out by 4',6-diamidino-2-phenylindole (DAPI) staining using fluorescence microscopy. In addition, TUNEL assay was performed to confirm apoptotic cell death. It was observed that cell viability, correlated with the LDH and glucose levels, changed according to the frequency and duration of RFR exposure. Four-hour exposure produced more pronounced effects than the other exposure durations. 1,800-MHz RFR had a larger impact on cell viability and Hep G2 injury than the RFR at 900 MHz. Morphological observations also supported the biochemical results indicating that most of the cells showed irregular nuclei pattern determined by using the DAPI staining, as well as TUNEL assay which shows DNA damage especially in the cells after 4 h of exposure to 1,800-MHz RFR. Our results indicate that the applications of 900- and 1,800-MHz (2 W/kg) RFR cause to decrease in the proliferation of the Hep G2 cells after 4 h of exposure. Further studies will be conducted on other frequency bands of RFR and longer duration of exposure.

  13. SerpinB1 Promotes Pancreatic β Cell Proliferation

    Energy Technology Data Exchange (ETDEWEB)

    El Ouaamari, Abdelfattah; Dirice, Ercument; Gedeon, Nicholas; Hu, Jiang; Zhou, Jian-Ying; Shirakawa, Jun; Hou, Lifei; Goodman, Jessica; Karampelias, Christos; Qiang, Guifeng; Boucher, Jeremie; Martinez, Rachael; Gritsenko, Marina A.; De Jesus, Dario F.; Kahraman, Sevim; Bhatt, Shweta; Smith, Richard D.; Beer, Hans-Dietmar; Jungtrakoon, Prapaporn; Gong, Yanping; Goldfine, Allison B.; Liew, Chong Wee; Doria, Alessandro; Andersson, Olov; Qian, Wei-Jun; Remold-O’Donnell, Eileen; Kulkarni, Rohit N.

    2016-01-01

    Compensatory β-cell growth in response to insulin resistance is a common feature in diabetes. We recently reported that liver-derived factors participate in this compensatory response in the liver insulin receptor knockout (LIRKO) mouse, a model of significant islet hyperplasia. Here we show that serpinB1 is a liver-derived secretory protein that controls β-cell proliferation. SerpinB1 is abundant in the hepatocyte secretome and sera derived from LIRKO mice. SerpinB1 and small molecule compounds that partially mimic serpinB1 activity enhanced proliferation of zebrafish, mouse and human β-cells. We report that serpinB1-induced β-cell replication requires protease inhibition activity and mice lacking serpinB1 exhibit attenuated β-cell replication in response to insulin resistance. Finally, SerpinB1-treatment of islets modulated signaling proteins in growth and survival pathways such as MAPK, PKA and GSK3. Together, these data implicate SerpinB1 as a protein that can potentially be harnessed to enhance functional β-cell mass in patients with diabetes.

  14. Cell proliferation in vitro modulates fibroblast collagenase activity

    International Nuclear Information System (INIS)

    Lindblad, W.J.; Flood, L.

    1986-01-01

    Collagenase enzyme activity is regulated by numerous control mechanisms which prevent excessive release and activation of this protease. A primary mechanism for regulating enzyme extracellular activity may be linked to cell division, therefore they have examined the release of collagenase by fibroblasts in vitro in response to cellular proliferation. Studies were performed using fibroblasts derived from adult rat dermis maintained in DMEM containing 10% newborn calf serum, 25 mM tricine buffer, and antibiotics. Cells between subculture 10 and 19 were used with enzyme activity determined with a 14 C-labelled soluble Type I collagen substrate with and without trypsin activation. Fibroblasts, trypsinized and plated at low density secreted 8.5 fold more enzyme than those cells at confluence (975 vs. 115 dpm/μg DNA). This diminution occurred gradually as the cells went from logrithmic growth towards confluence. Confluent fibroblast monolayers were scraped in a grid arrangement, stimulating the remaining cells to divide, without exposure to trypsin. Within 24-48 hr postscraping enzyme levels had increased 260-400%, accompanied by enhanced incorporation of 3 H-thymidine and 3 H-uridine into cell macromolecules. The burst of enzyme release began to subside 12 hr later. These results support a close relationship between fibroblast proliferation and collagenase secretion

  15. Effects of drinking desalinated seawater on cell viability and proliferation.

    Science.gov (United States)

    Macarrão, Camila Longhi; Bachi, André Luis Lacerda; Mariano, Mario; Abel, Lucia Jamli

    2017-06-01

    Desalination of seawater is becoming an important means to address the increasing scarcity of freshwater resources in the world. Seawater has been used as drinking water in the health, food, and medical fields and various beneficial effects have been suggested, although not confirmed. Given the presence of 63 minerals and trace elements in drinking desalinated seawater (63 DSW), we evaluated their effects on the behavior of tumorigenic and nontumorigenic cells through the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay and annexin-V-fluorescein isothiocyanate/propidium iodide staining. Our results showed that cell viability and proliferation in the presence of 63 DSW were significantly greater than in mineral water and in the presence of fetal bovine serum in a dose-dependent manner. Furthermore, 63 DSW showed no toxic effect on murine embryonic fibroblast (NIH-3T3) and murine melanoma (B16-F10) cells. In another assay, we also showed that pre-treatment of non-adherent THP-1 cells with 63 DSW reduces apoptosis incidence, suggesting a protective effect against cell death. We conclude that cell viability and proliferation were improved by the mineral components of 63 DSW and this effect can guide further studies on health effects associated with DSW consumption.

  16. Illegitimate WNT signaling promotes proliferation of multiple myeloma cells

    Science.gov (United States)

    Derksen, Patrick W. B.; Tjin, Esther; Meijer, Helen P.; Klok, Melanie D.; Mac Gillavry, Harold D.; van Oers, Marinus H. J.; Lokhorst, Henk M.; Bloem, Andries C.; Clevers, Hans; Nusse, Roel; van der Neut, Ronald; Spaargaren, Marcel; Pals, Steven T.

    2004-01-01

    The unrestrained growth of tumor cells is generally attributed to mutations in essential growth control genes, but tumor cells are also influenced by signals from the environment. In multiple myeloma (MM), the factors and signals coming from the bone marrow microenvironment are possibly even essential for the growth of the tumor cells. As targets for intervention, these signals may be equally important as mutated oncogenes. Given their oncogenic potential, WNT signals form a class of paracrine growth factors that could act to influence MM cell growth. In this paper, we report that MM cells have hallmarks of active WNT signaling, whereas the cells have not undergone detectable mutations in WNT signaling genes such as adenomatous polyposis coli and β-catenin (CTNNB1). We show that the malignant MM plasma cells overexpress β-catenin, including its N-terminally unphosphorylated form, suggesting active β-catenin/T cell factor-mediated transcription. Further accumulation and nuclear localization of β-catenin, and/or increased cell proliferation, was achieved by stimulation of WNT signaling with either Wnt3a, LiCl, or the constitutively active S33Y mutant of β-catenin. In contrast, by blocking WNT signaling by dominant-negative T cell factor, we can interfere with the growth of MM cells. We therefore suggest that MM cells are dependent on an active WNT signal, which may have important implications for the management of this incurable form of cancer. PMID:15067127

  17. Inosine Released from Dying or Dead Cells Stimulates Cell Proliferation via Adenosine Receptors

    Directory of Open Access Journals (Sweden)

    Yi Zhao

    2017-04-01

    Full Text Available IntroductionMany antitumor therapies induce apoptotic cell death in order to cause tumor regression. Paradoxically, apoptotic cells are also known to promote wound healing, cell proliferation, and tumor cell repopulation in multicellular organisms. We aimed to characterize the nature of the regenerative signals concentrated in the micromilieu of dead and dying cells.MethodsCultures of viable melanoma B16F10 cells, mouse fibroblasts, and primary human fibroblast-like synoviocytes (FLS in the presence of dead and dying cells, their supernatants (SNs, or purified agonists and antagonists were used to evaluate the stimulation of proliferation. Viable cell quantification was performed by either flow cytometry of harvested cells or by crystal violet staining of adherent cells. High-performance liquid chromatography and liquid chromatography coupled with mass spectrometry of cell SNs were deployed to identify the nature of growth-promoting factors. Coimplantation of living cells in the presence of SNs collected from dead and dying cells and specific agonists was used to evaluate tumor growth in vivo.ResultsThe stimulation of proliferation of few surviving cells by bystander dead cells was confirmed for melanoma cells, mouse fibroblasts, and primary FLS. We found that small soluble molecules present in the protein-free fraction of SNs of dead and dying cells were responsible for the promotion of proliferation. The nucleoside inosine released by dead and dying cells acting via adenosine receptors was identified as putative inducer of proliferation of surviving tumor cells after irradiation and heat treatment.ConclusionInosine released by dead and dying cells mediates tumor cell proliferation via purinergic receptors. Therapeutic strategies surmounting this pathway may help to reduce the rate of recurrence after radio- and chemotherapy.

  18. Immunomodulating effects of heparin on human B cell proliferation

    International Nuclear Information System (INIS)

    Wasik, Maria; Stepien-Sopniewska, Barbara; Gorski, Andrzej

    1993-01-01

    Recent data indicate that heparin may act as an immunomodulator. In this paper we have analyzed the effect of this agent on human B cell proliferation ''in vitro'' induced by ''S. aureus'' Cowan. The action of heparin is complex, but there was a trend for inhibition of B cell responses obtained from defibrinated but not heparinized blood samples. This suggest that heparin interacts with platelet products (growth factors, cytokines) and the results of such interactions determine the final effect. (author). 6 refs, 4 figs

  19. Intestinal cell proliferation following hyperthermia-radiation combinations

    International Nuclear Information System (INIS)

    Burholt, D.R.; Wilkinson, D.A.; Shrivastava, P.N.

    1987-01-01

    The present work is an investigation of the extent to which hyperthermia enhances x-ray induced inhibition of intestinal epithelial cell proliferation in mice. Hyperthermia was achieved by whole body immersion of anesthetized ice in a temperature controlled water bath (+-0.1 0 C). Post-treatment proliferative activity was monitored by determining the incorporation of /sup 3/H-TdR into intestinal crypt cells and by the counting of epithelial cell mitotic figures. Initial levels of cell kill were assessed by the microcolony crypt survival technique. All heat treatments were 41.5 0 C for 0.5h. Heat alone reduced the /sup 3/H-TdR incorporation to 50% of the control value by 2h post-treatment. This was followed by a return to control value by 10h and a slight hyperplasia at 24h. Heat either immediately before or after 2Gy abdominal field x-irradiation produced a prolonged period of depressed cell proliferation: /sup 3/H-TdR incorporation remained below control value for the first 24h. As the heat and radiation were separated in time from each other (up to 4h) the interaction between the two decreased. The development of thermotolerance was observed following the second and third treatment during either a heat-only or a heat-radiation multifraction treatments schedule with the treatment spaced 24h apart

  20. Infection and Proliferation of Giant Viruses in Amoeba Cells.

    Science.gov (United States)

    Takemura, Masaharu

    2016-01-01

    Acanthamoeba polyphaga mimivirus, the first discovered giant virus with genome size and particle size much larger than previously discovered viruses, possesses several genes for translation and CRISPER Cas system-like defense mechanism against virophages, which co-infect amoeba cells with the giant virus and which inhibit giant virus proliferation. Mimiviruses infect amoeba cells by phagocytosis and release their DNA into amoeba cytoplasm through their stargate structure. After infection, giant virion factories (VFs) form in amoeba cytoplasm, followed by DNA replication and particle formation at peripheral regions of VF. Marseilleviruses, the smallest giant viruses, infect amoeba cells by phagocytosis or endocytosis, form larger VF than Mimivirus's VF in amoeba cytoplasm, and replicate their particles. Pandoraviruses found in 2013 have the largest genome size and particle size among all viruses ever found. Pandoraviruses infect amoeba cells by phagocytosis and release their DNA into amoeba cytoplasm through their mouth-like apical pores. The proliferation of Pandoraviruses occurs along with nucleus disruption. New virions form at the periphery of the region formerly occupied by the amoeba cell nucleus.

  1. Effect of low dose radiation (LDR) on biological activity of NK cell

    International Nuclear Information System (INIS)

    Yang Liyun; Lin Meixiong; Luo Min; Ran Min; Liang Xuefei

    2006-01-01

    Objective: To study the in vitro and in vivo effect of LDR on the proliferation and killing activity of mouse NK cells with exploitation of the related mechanism of signal transduction. The effect of infused NK cells on inhibiton of oncogenesis and tumor burden regression was also studied. Methods: Mononuclear cells extracted from mouse spleen were treated with immunomagnetic bead for the isolation of CD3 - /CD16 + , CD56 + cells. After verified with flowcytometry, these NK cells were cultured with mice splenic cells (irradiated with 20Gy 60 Co gamma ray) as feeder cells and rhIL-2 as induction factor for 3 rounds (5 days each round). Specimens of cultured NK cells were treated with different doses of radiation (25mGy, 75mGy, 200mGy, 500mGy), the proliferation index (PI) with tumoreidal activity on K562 cells (with 3 H-TdR) incorporation was examined at 4h, 24h, 48h, 72h after irradiation respectively. The role of P38MAPK signal pathway in the LDR effect was examined with adding either inhibitor (SB203580) or activator (P79350) of P38MAPK into the culture and measuring the PI, Killing activity (as expression of the related factors IFN-gamma, FasL, perforin) of NK cells thereafter. The in vivo test involved exposing mice to whole body 25mGy irradiation, harvesting splenic NK cells at 4h, 24h, 48h, 72h later respectively and performing the above-described in vitro procedures. Inhibition of oncogenesis was examined in vivo with infusion of cultured NK cells (LDR treated vs LDR non-treated) 10 days after infusion of K562 cells into mice and examination of hepatic/splenic CD 13+ , S-stage cells and peripheral blood tumor cells in the sacrificed animal another 10 days later. Also, K562 cells were innoculated subcutaneously into mice. After tumor nodule formation (2.0 x 2.0 mm), NK cells (LDR treated vs non-treated) were infused and regression of the tumor nodule with the weight of hepatic tumor mass was noticed in sacrificed animals on d 8 and the survival rate on d 40

  2. Patterns of cell proliferation and cell death in the developing retina and optic tectum of the brown trout.

    NARCIS (Netherlands)

    Candal, E.; Anadon, R.; Grip, W.J. de; Rodriguez-Moldes, I.

    2005-01-01

    We have analyzed the patterns of cell proliferation and cell death in the retina and optic tectum of the brown trout (Salmo trutta fario) throughout embryonic and postembryonic stages. Cell proliferation was detected by immunohistochemistry with an antibody against the proliferating cell nuclear

  3. Inhibition of Zoledronic Acid on Cell Proliferation and Invasion of Lung Cancer Cell Line 95D

    Directory of Open Access Journals (Sweden)

    Mingming LI

    2009-03-01

    Full Text Available Background and objective Abnormal proliferation and metastasis is the basic characteristic of malignant tumors. The aim of this work is to explore the effects of zoledronic acid on cell proliferation and invasion in lung cancer cell line 95D. Methods The effect of zoledrnic acid (ZOL on proliferation of lung cancer cell line 95D was detected by MTT. The expression of proliferation and invasion-relation genes and proteins were detected by Western blot, RT-PCR and immunofluorescence. Changes of invasion of lung cancer cell numbers were measured by polycarbonates coated with Matrigel. Results ZOL could inhibit the proliferation of lung cancer cell line 95D in vitro in a time-dependant and a dose-dependant manner. With time extending after ZOL treated, the mRNA expresion of VEGF, MMP9, MMP2 and protein expression of VEGF, MMP9, ERK1/ ERK2 were decreased. The results of Tanswell invasion showed the numbers of invasive cells were significantly reduced in 95D cells treated with ZOL 4 d and 6 d later. Conclusion ZOL could inhibit cell proliferation and invasion of lung cancer cell line 95D.

  4. Effects of Uptake of Hydroxyapatite Nanoparticles into Hepatoma Cells on Cell Adhesion and Proliferation

    Directory of Open Access Journals (Sweden)

    Meizhen Yin

    2014-01-01

    Full Text Available Hydroxyapatite nanoparticles (nano-HAPs were prepared by homogeneous precipitation, and size distribution and morphology of these nanoparticles were determined by laser particle analysis and transmission electron microscopy, respectively. Nano-HAPs were uniformly distributed, with rod-like shapes sizes ranging from 44.6 to 86.8 nm. Attached overnight, suspended, and proliferating Bel-7402 cells were repeatedly incubated with nano-HAPs. Inverted microscopy, transmission electron microscopy, and fluorescence microscopy were used to observe the cell adhesion and growth, the culture medium containing nano-HAPs, the cell ultrastructure, and intracellular Ca2+ labeled with a fluo-3 calcium fluorescent probe. The results showed that nano-HAPs inhibited proliferation of Bel-7402 cells and, caused an obvious increase in the concentration of intracellular Ca2+, along with significant changes in the cell ultrastructure. Moreover, nano-HAPs led suspended cells and proliferating cells after trypsinized that did not attach to the bottom of the culture bottle died. Nano-HAPs continuously entered these cells. Attached, suspended, and proliferating cells endocytosed nano-HAPs, and nanoparticle-filled vesicles were in the cytoplasm. Therefore, hepatoma cellular uptake of nano-HAPs through endocytosis was very active and occurred continuously. Nano-HAPs affected proliferation and adhesion of hepatoma cells probably because uptake of nano-HAPs blocked integrin-mediated cell adhesion, which may have potential significance in inhibiting metastatic cancer cells to their target organ.

  5. Low dose perfluorooctanoate exposure promotes cell proliferation in a human non-tumor liver cell line

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Hongxia; Cui, Ruina [Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101 (China); Guo, Xuejiang [State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing 210029 (China); Hu, Jiayue [Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101 (China); Dai, Jiayin, E-mail: daijy@ioz.ac.cn [Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101 (China)

    2016-08-05

    Highlights: • Differential expression of proteins induced by PFOA in HL-7702 was identified. • Most of the differentially expressed proteins are related to cell proliferation. • A low dose of PFOA stimulates HL-7702 cell proliferation. • A high dose of PFOA inhibits HL-7702 cell proliferation. - Abstract: Perfluorooctanoate (PFOA) is a well-known persistent organic pollutant widely found in the environment, wildlife and humans. Medical surveillance and experimental studies have investigated the potential effects of PFOA on human livers, but the hepatotoxicity of PFOA on humans and its underlying mechanism remain to be clarified. We exposed a human liver cell line (HL-7702) to 50 μM PFOA for 48 h and 96 h, and identified 111 significantly differentially expressed proteins by iTRAQ analysis. A total of 46 proteins were related to cell proliferation and apoptosis. Through further analysis of the cell cycle, apoptosis and their related proteins, we found that low doses of PFOA (50–100 μM) promoted cell proliferation and numbers by promoting cells from the G1 to S phases, whereas high doses of PFOA (200–400 μM) led to reduced HL-7702 cell numbers compared with that of the control mainly due to cell cycle arrest in the G0/G1 phase. To our knowledge, this is the first report on the promotion of cell cycle progression in human cells following PFOA exposure.

  6. Low dose perfluorooctanoate exposure promotes cell proliferation in a human non-tumor liver cell line

    International Nuclear Information System (INIS)

    Zhang, Hongxia; Cui, Ruina; Guo, Xuejiang; Hu, Jiayue; Dai, Jiayin

    2016-01-01

    Highlights: • Differential expression of proteins induced by PFOA in HL-7702 was identified. • Most of the differentially expressed proteins are related to cell proliferation. • A low dose of PFOA stimulates HL-7702 cell proliferation. • A high dose of PFOA inhibits HL-7702 cell proliferation. - Abstract: Perfluorooctanoate (PFOA) is a well-known persistent organic pollutant widely found in the environment, wildlife and humans. Medical surveillance and experimental studies have investigated the potential effects of PFOA on human livers, but the hepatotoxicity of PFOA on humans and its underlying mechanism remain to be clarified. We exposed a human liver cell line (HL-7702) to 50 μM PFOA for 48 h and 96 h, and identified 111 significantly differentially expressed proteins by iTRAQ analysis. A total of 46 proteins were related to cell proliferation and apoptosis. Through further analysis of the cell cycle, apoptosis and their related proteins, we found that low doses of PFOA (50–100 μM) promoted cell proliferation and numbers by promoting cells from the G1 to S phases, whereas high doses of PFOA (200–400 μM) led to reduced HL-7702 cell numbers compared with that of the control mainly due to cell cycle arrest in the G0/G1 phase. To our knowledge, this is the first report on the promotion of cell cycle progression in human cells following PFOA exposure.

  7. Efficacy of ponatinib against ABL tyrosine kinase inhibitor-resistant leukemia cells

    International Nuclear Information System (INIS)

    Okabe, Seiichi; Tauchi, Tetsuzo; Tanaka, Yuko; Ohyashiki, Kazuma

    2013-01-01

    Highlights: •Efficacy of ponatinib against ABL tyrosine kinase inhibitor-resistant leukemia cells okabe et al. •Imatinib or nilotinib resistance was involved Src family kinase. •The BCR-ABL point mutation (E334V) was highly resistant to imatinib or nilotinib. •Ponatinib was a powerful strategy against imatinib or nilotinib resistant Ph-positive cells. -- Abstract: Because a substantial number of patients with chronic myeloid leukemia acquire resistance to ABL tyrosine kinase inhibitors (TKIs), their management remains a challenge. Ponatinib, also known as AP24534, is an oral multi-targeted TKI. Ponatinib is currently being investigated in a pivotal phase 2 clinical trial. In the present study, we analyzed the molecular and functional consequences of ponatinib against imatinib- or nilotinib-resistant (R) K562 and Ba/F3 cells. The proliferation of imatinib- or nilotinib-resistant K562 cells did not decrease after treatment with imatinib or nilotinib. Src family kinase Lyn was activated. Point mutation Ba/F3 cells (E334 V) were also highly resistant to imatinib and nilotinib. Treatment with ponatinib for 72 h inhibited the growth of imatinib- and nilotinib-resistant cells. The phosphorylation of BCR-ABL, Lyn, and Crk-L was reduced. This study demonstrates that ponatinib has an anti-leukemia effect by reducing ABL and Lyn kinase activity and this information may be of therapeutic relevance

  8. Efficacy of ponatinib against ABL tyrosine kinase inhibitor-resistant leukemia cells

    Energy Technology Data Exchange (ETDEWEB)

    Okabe, Seiichi, E-mail: okabe@tokyo-med.ac.jp; Tauchi, Tetsuzo; Tanaka, Yuko; Ohyashiki, Kazuma

    2013-06-07

    Highlights: •Efficacy of ponatinib against ABL tyrosine kinase inhibitor-resistant leukemia cells okabe et al. •Imatinib or nilotinib resistance was involved Src family kinase. •The BCR-ABL point mutation (E334V) was highly resistant to imatinib or nilotinib. •Ponatinib was a powerful strategy against imatinib or nilotinib resistant Ph-positive cells. -- Abstract: Because a substantial number of patients with chronic myeloid leukemia acquire resistance to ABL tyrosine kinase inhibitors (TKIs), their management remains a challenge. Ponatinib, also known as AP24534, is an oral multi-targeted TKI. Ponatinib is currently being investigated in a pivotal phase 2 clinical trial. In the present study, we analyzed the molecular and functional consequences of ponatinib against imatinib- or nilotinib-resistant (R) K562 and Ba/F3 cells. The proliferation of imatinib- or nilotinib-resistant K562 cells did not decrease after treatment with imatinib or nilotinib. Src family kinase Lyn was activated. Point mutation Ba/F3 cells (E334 V) were also highly resistant to imatinib and nilotinib. Treatment with ponatinib for 72 h inhibited the growth of imatinib- and nilotinib-resistant cells. The phosphorylation of BCR-ABL, Lyn, and Crk-L was reduced. This study demonstrates that ponatinib has an anti-leukemia effect by reducing ABL and Lyn kinase activity and this information may be of therapeutic relevance.

  9. Nanoscale crystallinity modulates cell proliferation on plasma sprayed surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Alan M. [School of Applied Sciences, University of Huddersfield, Huddersfield HD1 3DH (United Kingdom); Paxton, Jennifer Z.; Hung, Yi-Pei; Hadley, Martin J.; Bowen, James; Williams, Richard L. [School of Chemical Engineering, University of Birmingham, Edgbaston, B15 2TT (United Kingdom); Grover, Liam M., E-mail: l.m.grover@bham.ac.uk [School of Chemical Engineering, University of Birmingham, Edgbaston, B15 2TT (United Kingdom)

    2015-03-01

    Calcium phosphate coatings have been applied to the surface of metallic prostheses to mediate hard and soft tissue attachment for more than 40 years. Most coatings are formed of high purity hydroxyapatite, and coating methods are often designed to produce highly crystalline surfaces. It is likely however, that coatings of lower crystallinity can facilitate more rapid tissue attachment since the surface will exhibit a higher specific surface area and will be considerably more reactive than a comparable highly crystalline surface. Here we test this hypothesis by growing a population of MC3T3 osteoblast-like cells on the surface of two types of hip prosthesis with similar composition, but with differing crystallinity. The surfaces with lower crystallinity facilitated more rapid cell attachment and increased proliferation rate, despite having a less heterogeneous surface topography. This work highlights that the influence of the crystallinity of HA at the nano-scale is dominant over macro-scale topography for cell adhesion and growth. Furthermore, crystallinity could be easily adjusted by without compromising coating purity. These findings could facilitate designing novel coated calcium phosphate surfaces that more rapidly bond tissue following implantation. - Highlights: • Crystallinity of HA at the nano-scale was dominant over macro-scale topography. • Lower crystallinity caused rapid cell attachment and proliferation rate. • Crystallinity could be easily adjusted by without compromising coating purity.

  10. Proliferation of human mammary cancer cells exposed to 27-hydroxycholesterol.

    Science.gov (United States)

    Cruz, Pamela; Torres, Cristian; Ramírez, María Eugenia; Epuñán, María José; Valladares, Luis Emilio; Sierralta, Walter Daniel

    2010-05-01

    The aim of the present study was to identify the possible mechanisms by which certain estradiol receptor (ER)-positive mammary tumor cells remain resistant to treatment with anti-estrogens or inhibitors of local estradiol (E(2)) production. To this end, we compared the proliferative effects on mammary cancer cells of the novel selective ER modulator 27-hydroxycholesterol (27OHC) to those of E(2), and evaluated their inhibition by ICI 182,780 (ICI). Analysis of the effects on the cell cycle of 27OHC and E(2) in the absence or presence of ICI was conducted. In ER-positive mammary tumor cells, we detected the blocking of 27OHC proliferation-stimulatory activity by simvastatin, as well as the inhibition of E(2)-stimulated proliferation by an α-fetoprotein-derived cyclic nonapeptide. The effects reported herein may be extrapolated to infiltrating mammary cancer, where the activity of local macrophages may stimulate tumor growth. We suggest that increased breast cancer growth in obese patients may be related to increased 27OHC circulatory levels.

  11. Nanoscale crystallinity modulates cell proliferation on plasma sprayed surfaces

    International Nuclear Information System (INIS)

    Smith, Alan M.; Paxton, Jennifer Z.; Hung, Yi-Pei; Hadley, Martin J.; Bowen, James; Williams, Richard L.; Grover, Liam M.

    2015-01-01

    Calcium phosphate coatings have been applied to the surface of metallic prostheses to mediate hard and soft tissue attachment for more than 40 years. Most coatings are formed of high purity hydroxyapatite, and coating methods are often designed to produce highly crystalline surfaces. It is likely however, that coatings of lower crystallinity can facilitate more rapid tissue attachment since the surface will exhibit a higher specific surface area and will be considerably more reactive than a comparable highly crystalline surface. Here we test this hypothesis by growing a population of MC3T3 osteoblast-like cells on the surface of two types of hip prosthesis with similar composition, but with differing crystallinity. The surfaces with lower crystallinity facilitated more rapid cell attachment and increased proliferation rate, despite having a less heterogeneous surface topography. This work highlights that the influence of the crystallinity of HA at the nano-scale is dominant over macro-scale topography for cell adhesion and growth. Furthermore, crystallinity could be easily adjusted by without compromising coating purity. These findings could facilitate designing novel coated calcium phosphate surfaces that more rapidly bond tissue following implantation. - Highlights: • Crystallinity of HA at the nano-scale was dominant over macro-scale topography. • Lower crystallinity caused rapid cell attachment and proliferation rate. • Crystallinity could be easily adjusted by without compromising coating purity

  12. Upregulation of LYAR induces neuroblastoma cell proliferation and survival.

    Science.gov (United States)

    Sun, Yuting; Atmadibrata, Bernard; Yu, Denise; Wong, Matthew; Liu, Bing; Ho, Nicholas; Ling, Dora; Tee, Andrew E; Wang, Jenny; Mungrue, Imran N; Liu, Pei Y; Liu, Tao

    2017-09-01

    The N-Myc oncoprotein induces neuroblastoma by regulating gene transcription and consequently causing cell proliferation. Paradoxically, N-Myc is well known to induce apoptosis by upregulating pro-apoptosis genes, and it is not clear how N-Myc overexpressing neuroblastoma cells escape N-Myc-mediated apoptosis. The nuclear zinc finger protein LYAR has recently been shown to modulate gene expression by forming a protein complex with the protein arginine methyltransferase PRMT5. Here we showed that N-Myc upregulated LYAR gene expression by binding to its gene promoter. Genome-wide differential gene expression studies revealed that knocking down LYAR considerably upregulated the expression of oxidative stress genes including CHAC1, which depletes intracellular glutathione and induces oxidative stress. Although knocking down LYAR expression with siRNAs induced oxidative stress, neuroblastoma cell growth inhibition and apoptosis, co-treatment with the glutathione supplement N-acetyl-l-cysteine or co-transfection with CHAC1 siRNAs blocked the effect of LYAR siRNAs. Importantly, high levels of LYAR gene expression in human neuroblastoma tissues predicted poor event-free and overall survival in neuroblastoma patients, independent of the best current markers for poor prognosis. Taken together, our data suggest that LYAR induces proliferation and promotes survival of neuroblastoma cells by repressing the expression of oxidative stress genes such as CHAC1 and suppressing oxidative stress, and identify LYAR as a novel co-factor in N-Myc oncogenesis.

  13. Ginkgo Biloba Extract Kaempferol Inhibits Cell Proliferation and Induces Apoptosis in Pancreatic Cancer Cells

    Science.gov (United States)

    Zhang, Yuqing; Chen, Aaron Y.; Li, Min; Chen, Changyi; Yao, Qizhi

    2010-01-01

    Background Kaempferol is one of the most important constituents in ginkgo flavonoids. Recent studies indicate kaempferol may have anti-tumor activities. The objective in this study was to determine the effect and mechanisms of kaempferol on pancreatic cancer cell proliferation and apoptosis. Materials and Methods Pancreatic cancer cell lines MIA PaCa-2 and Panc-1 were treated with Kampferol, and the inhibitory effects of kaempferol on pancreatic cancer cell proliferation were examined by direct cell counting, 3H-thymidine incorporation and MTS assay. Lactate dehydrogenase (LDH) release from cells was determined as an index of cytotoxicity. Apoptosis was analyzed by TUNEL assay. Results Upon the treatment with 70 μM kaempferol for 4 days, MIA PaCa-2 cell proliferation was significantly inhibited by 79% and 45.7% as determined by direct cell counting and MTS assay, respectively, compared with control cells (Pkaempferol significantly inhibited Panc-1 cell proliferation. Kaempferol treatment also significantly reduced 3H-thymidine incorporation in both MIA PaCa-2 and Panc-1 cells. Combination treatment of low concentrations of kaempferol and 5-fluorouracil (5-FU) showed an additive effect on the inhibition of MIA PaCa-2 cell proliferation. Furthermore, kaempferol had a significantly less cytotoxicity than 5-FU in normal human pancreatic ductal epithelial cells (P=0.029). In both MIA PaCa-2 and Panc-1 cells, apoptotic cell population was increased when treated with kaempferol in a concentration-dependent manner. Conclusions Ginkgo biloba extract kaempferol effectively inhibits pancreatic cancer cell proliferation and induces cancer cell apoptosis, which may sensitize pancreatic tumor cells to chemotherapy. Kaempferol may have clinical applications as adjuvant therapy in the treatment of pancreatic cancer. PMID:18570926

  14. Conditional IL-2 gene deletion: consequences for T cell proliferation

    Directory of Open Access Journals (Sweden)

    Kendall A Smith

    2012-05-01

    Full Text Available To explore the role of interleukin-2 (IL-2 in T cell proliferation, and to circumvent the IL-2 deficiency autoimmune syndrome of conventional il2 gene deletion, mice were created to allow conditional il2 gene deletion when treated with the estrogen analogue, tamoxifen (TAM as adults. Splenocytes from four different mouse strains, C57Bl/6 wild type (WT, conventional IL-2 (-/-, TAM-treated Cre recombinase negative (Cre-/IL2fl/fl, and Cre+/IL-2fl/fl (Cre+, were activated with anti-CD3 and anti-CD28, and monitored for CD4+ and CD8+ T cell lymphocyte blastogenesis, aerobic glycolysis, BrdU incorporation into newly synthesized DNA, and CFSE dye dilution to monitor cell division. IL-2 production was monitored by quantitative ELISA and multiple additional cytokines were monitored by protein-bead arrays. Splenocytes from conventional IL-2 (-/- and TAM-treated Cre+ mice resulted in undetectable IL-2 production, so that both strains were IL-2 deficient. As monitored by flow cytometry, activated CD4+ and CD8+ T cells from WT, Cre+ and Cre- mice all underwent blastogenesis, whereas far fewer cells from conventional IL-2 (-/- mice did so. By comparison, only cells from IL-2 sufficient WT and Cre- switched to aerobic glycolysis as evidenced by a drop in media pH. Blastogenesis was mirrored by BrdU incorporation and CFSE dye dilution by CD4+ and CD8+ T cells from WT, Cre+ and Cre- mice, which were all equivalent, while proliferation of cells from conventional IL-2 (-/- mice was compromised. Splenocytes from IL-2 deficient conventional IL-2 (-/- mice produced low or undetectable other γc-chain cytokines (IL-4, IL-7, IL-9, IL-13, IL-15, and IL-21, whereas production of these γc-chain cytokines from IL-2-deficient conditional IL-2 (-/- Cre+ mice were comparable with WT and Cre- mice. These results indicate that CD4+ and CD8+ T cell blastogenesis cannot be attributable to IL-2 alone, but a switch to aerobic glycolysis is attributable to IL-2, and proliferation

  15. The effect of stem cell factor on proliferation of human endometrial CD146+ cells

    Directory of Open Access Journals (Sweden)

    Mehri Fayazi

    2016-07-01

    Full Text Available Background: Stem cell factor (SCF is a transcriptional factor which plays crucial roles in normal proliferation, differentiation and survival in a range of stem cells. Objective: The aim of the present study was to examine the proliferation effect of different concentrations of SCF on expansion of human endometrial CD146+ cells. Materials and Methods: In this experimental study, total populations of isolated human endometrial suspensions after fourth passage were isolated by magnetic activated cell sorting (MACS into CD146+ cells. Human endometrial CD146+ cells were karyotyped and tested for the effect of SCF on proliferation of CD146+ cells, then different concentrations of 0, 12.5, 25, 50 and 100 ng/ml was carried out and mitogens-stimulated endometrial CD146+ cells proliferation was assessed by MTT assay. Results: Chromosomal analysis showed a normal metaphase spread and 46XX karyotype. The proliferation rate of endometrial CD146P + P cells in the presence of 0, 12.5, 25, 50 and 100 ng/ml SCF were 0.945±0.094, 0.962±0.151, 0.988±0.028, 1.679±0.012 and 1.129±0.145 respectively. There was a significant increase in stem/ stromal cell proliferation following in vitro treatment by 50 ng/ml than other concentrations of SCF (p=0.01. Conclusion: The present study suggests that SCF could have effect on the proliferation and cell survival of human endometrial CD146P+P cells and it has important implications for medical sciences and cell therapies

  16. Proliferating cells in psoriatic dermis are comprised primarily of T cells, endothelial cells, and factor XIIIa+ perivascular dendritic cells

    International Nuclear Information System (INIS)

    Morganroth, G.S.; Chan, L.S.; Weinstein, G.D.; Voorhees, J.J.; Cooper, K.D.

    1991-01-01

    Determination of the cell types proliferating in the dermis of patients with psoriasis should identify those cells experiencing activation or responding to growth factors in the psoriatic dermal milieu. Toward that end, sections of formalin-fixed biopsies obtained from 3H-deoxyuridine (3H-dU)-injected skin of eight psoriatic patients were immunostained, followed by autoradiography. Proliferating dermal cells exhibit silver grains from tritium emissions. The identity of the proliferating cells could then be determined by simultaneous visualization with antibodies specific for various cell types. UCHL1+ (CD45RO+) T cells (recall antigen-reactive helper T-cell subset) constituted 36.6 +/- 3.1% (mean +/- SEM, n = 6) of the proliferating dermal cells in involved skin, whereas Leu 18+ (CD45RA+) T cells (recall antigen naive T-cell subsets) comprised only 8.7 +/- 1.5% (n = 6). The Factor XIIIa+ dermal perivascular dendritic cell subset (24.9 +/- 1.5% of proliferating dermal cells, n = 6) and Factor VIII+ endothelial cells represented the two other major proliferating populations in lesional psoriatic dermis. Differentiated tissue macrophages, identified by phase microscopy as melanophages or by immunostaining with antibodies to Leu M1 (CD15) or myeloid histiocyte antigen, comprised less than 5% of the proliferating population in either skin type. In addition to calculating the relative proportions of these cells to each other as percent, we also determined the density of cells, in cells/mm2 of tissue. The density of proliferating cells within these populations was increased in involved versus uninvolved skin: UCHL1+, 9.0 +/- 1.7 cells/mm2 versus 1.8 +/- 0.6 cells/mm2, p less than 0.01; Factor XIIIa+, 6.0 +/- 0.7 cells/mm2 versus 1.5 +/- 0.5 cells/mm2, p less than 0.01; Factor VIII+, 5.5 +/- 1.4 cells/mm2 versus 0.0 cells/mm2, p less than 0.05

  17. Effects of glucocorticoid hormones on cell proliferation in dimethylhydrazine-induced tumours in rat colon.

    Science.gov (United States)

    Tutton, P J; Barkla, D H

    1981-01-01

    Adrenocortical hormones have previously been shown to influence cell proliferation in many tissues. In this report, their influence on cell proliferation in the colonic crypt epithelium and in colonic adenocarcinomata is compared. Colonic tumour cell proliferation was found to be retarded following adrenalectomy and this retardation was reversible by administration of hydrocortisone, or by administration of synthetic steroids with predominantly glucocorticoid activity. Tumour cell proliferation in adrenalectomized rats was not promoted by the mineralocorticoid hormone aldosterone. Neither adrenalectomy, nor adrenocortical hormone treatment, significantly influenced colonic crypt cell proliferation.

  18. Hyaluronan in aged collagen matrix increases prostate epithelial cell proliferation

    Science.gov (United States)

    Damodarasamy, Mamatha; Vernon, Robert B.; Chan, Christina K.; Plymate, Stephen R.; Wight, Thomas N.

    2015-01-01

    The extracellular matrix (ECM) of the prostate, which is comprised primarily of collagen, becomes increasingly disorganized with age, a property that may influence the development of hyperplasia and cancer. Collageous ECM extracted from the tails of aged mice exhibits many characteristics of collagen in aged tissues, including the prostate. When polymerized into a 3-dimensional (3D) gel, these collagen extracts can serve as models for the study of specific cell-ECM interactions. In the present study, we examined the behaviors of human prostatic epithelial cell lines representing normal prostate epithelial cells (PEC), benign prostatic hyperplasia (BPH-1), and adenocarcinoma (LNCaP) cultured in contact with 3D gels made from collagen extracts of young and aged mice. We found that proliferation of PEC, BPH-1, and LNCaP cells were all increased by culture on aged collagen gels relative to young collagen gels. In examining age-associated differences in the composition of the collagen extracts, we found that aged and young collagen had a similar amount of several collagen-associated ECM components, but aged collagen had a much greater content of the glycosaminoglycan hyaluronan (HA) than young collagen. The addition of HA (of similar size and concentration to that found in aged collagen extracts) to cells placed in young collagen elicited significantly increased proliferation in BPH-1 cells, but not in PEC or LNCaP cells, relative to controls not exposed to HA. Of note, histochemical analyses of human prostatic tissues showed significantly higher expression of HA in BPH and prostate cancer stroma relative to stroma of normal prostate. Collectively, these results suggest that changes in ECM involving increased levels of HA contribute to the growth of prostatic epithelium with aging. PMID:25124870

  19. RUNX3 is involved in caspase-3-dependent apoptosis induced by a combination of 5-aza-CdR and TSA in leukaemia cell lines.

    Science.gov (United States)

    Zhai, Feng-Xian; Liu, Xiang-Fu; Fan, Rui-Fang; Long, Zi-Jie; Fang, Zhi-Gang; Lu, Ying; Zheng, Yong-Jiang; Lin, Dong-Jun

    2012-03-01

    Epigenetic therapy has had a significant impact on the management of haematologic malignancies. The aim of this study was to assess whether 5-aza-CdR and TSA inhibit the growth of leukaemia cells and induce caspase-3-dependent apoptosis by upregulating RUNX3 expression. K562 and Reh cells were treated with 5-aza-CdR, TSA or both compounds. RT-PCR and Western blot analyses were used to examine the expression of RUNX3 at the mRNA and protein levels, respectively. Immunofluorescence microscopy was used to detect the cellular location of RUNX3. Additionally, after K562 cells were transfected with RUNX3, apoptosis and proliferation were studied using Annexin V staining and MTT assays. The expression of RUNX3 in leukaemia cell lines was markedly less than that in the controls. Demethylating drug 5-aza-CdR could induce RUNX3 expression, but the combination of TSA and 5-aza-CdR had a greater effect than did treatment with a single compound. The combination of 5-aza-CdR and TSA induced the translocation of RUNX3 from the cytoplasm into the nucleus. TSA enhanced apoptosis induced by 5-aza-CdR, and Annexin V and Hoechst 33258 staining showed that the combination induced apoptosis but not necrosis. Furthermore, apoptosis was dependent on the caspase-3 pathway. RUNX3 overexpression in K562 cells led to growth inhibition and apoptosis and potentiated the effects of 5-aza-CdR induction. RUNX3 plays an important role in leukaemia cellular functions, and the induction of RUNX3-mediated effects may contribute to the therapeutic value of combination TSA and 5-aza-CdR treatment.

  20. Dynamic mapping of genes controlling cancer stem cell proliferation

    Directory of Open Access Journals (Sweden)

    Zhong eWang

    2012-05-01

    Full Text Available The growing evidence that cancer originates from stem cells holds a great promise to eliminate this disease by designing specific drug therapies for removing cancer stem cells. Translation of this knowledge into predictive tests for the clinic is hampered due to the lack of methods to discriminate cancer stem cells from non-cancer stem cells. Here, we address this issue by describing a conceptual strategy for identifying the genetic origins of cancer stem cells. The strategy incorporates a high-dimensional group of differential equations that characterizes the proliferation, differentiation, and reprogramming of cancer stem cells in a dynamic cellular and molecular system. The deployment of robust mathematical models will help uncover and explain many still unknown aspects of cell behavior, tissue function, and network organization related to the formation and division of cancer stem cells. The statistical method developed allows biologically meaningful hypotheses about the genetic control mechanisms of carcinogenesis and metastasis to be tested in a quantitative manner.

  1. Oesophageal epithelial cell proliferation and food consumption patterns following irradiation

    International Nuclear Information System (INIS)

    Burholt, D.R.

    1986-01-01

    The murine data presented illustrate the influence of food consumption on the proliferative rate of the oesophageal epithelium during recovery from radiation damage. Refeeding at a time before the initiation of the normal hyperplastic response results in a decreased time interval between treatment and increased rates of cell proliferation, while reduced food consumption during the normal period of hyperproliferation results in reduced proliferative activity. The finding that recovery kinetics may be altered by changing food consumption patterns should be an important consideration in the analysis of antineoplastic agent-induced proliferative perturbations, as many treatments themselves produce reduced levels of food consumption. (UK)

  2. Del-1 overexpression potentiates lung cancer cell proliferation and invasion

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    Lee, Seung-Hwan; Kim, Dong-Young; Jing, Feifeng; Kim, Hyesoon [Department of Biomedical Sciences, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Yun, Chae-Ok [Department of Bioengineering, College of Engineering, Hanyang University, Seoul (Korea, Republic of); Han, Deok-Jong [Department of Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Choi, Eun Young, E-mail: choieun@ulsan.ac.kr [Department of Biomedical Sciences, University of Ulsan College of Medicine, Seoul (Korea, Republic of)

    2015-12-04

    Developmental endothelial locus-1 (Del-1) is an endogenous anti-inflammatory molecule that is highly expressed in the lung and the brain and limits leukocyte migration to these tissues. We previously reported that the expression of Del-1 is positively regulated by p53 in lung endothelial cells. Although several reports have implicated the altered expression of Del-1 gene in cancer patients, little is known about its role in tumor cells. We here investigated the effect of Del-1 on the features of human lung carcinoma cells. Del-1 mRNA was found to be significantly decreased in the human lung adenocarcinoma cell lines A549 (containing wild type of p53), H1299 (null for p53) and EKVX (mutant p53), compared to in human normal lung epithelial BEAS-2B cells and MRC-5 fibroblasts. The decrease of Del-1 expression was dependent on the p53 activity in the cell lines, but not on the expression of p53. Neither treatment with recombinant human Del-1 protein nor the introduction of adenovirus expressing Del-1 altered the expression of the apoptosis regulators BAX, PUMA and Bcl-2. Unexpectedly, the adenovirus-mediated overexpression of Del-1 gene into the lung carcinoma cell lines promoted proliferation and invasion of the lung carcinoma cells, as revealed by BrdU incorporation and transwell invasion assays, respectively. In addition, overexpression of the Del-1 gene enhanced features of epithelial–mesenchymal transition (EMT), such as increasing vimentin while decreasing E-cadherin in A549 cells, and increases in the level of Slug, an EMT-associated transcription regulator. Our findings demonstrated for the first time that there are deleterious effects of high levels of Del-1 in lung carcinoma cells, and suggest that Del-1 may be used as a diagnostic or prognostic marker for cancer progression, and as a novel therapeutic target for lung carcinoma. - Highlights: • Developmental Endothelial Locus-1 (Del-1) expression is downregulated in human lung cancer cells.

  3. Del-1 overexpression potentiates lung cancer cell proliferation and invasion

    International Nuclear Information System (INIS)

    Lee, Seung-Hwan; Kim, Dong-Young; Jing, Feifeng; Kim, Hyesoon; Yun, Chae-Ok; Han, Deok-Jong; Choi, Eun Young

    2015-01-01

    Developmental endothelial locus-1 (Del-1) is an endogenous anti-inflammatory molecule that is highly expressed in the lung and the brain and limits leukocyte migration to these tissues. We previously reported that the expression of Del-1 is positively regulated by p53 in lung endothelial cells. Although several reports have implicated the altered expression of Del-1 gene in cancer patients, little is known about its role in tumor cells. We here investigated the effect of Del-1 on the features of human lung carcinoma cells. Del-1 mRNA was found to be significantly decreased in the human lung adenocarcinoma cell lines A549 (containing wild type of p53), H1299 (null for p53) and EKVX (mutant p53), compared to in human normal lung epithelial BEAS-2B cells and MRC-5 fibroblasts. The decrease of Del-1 expression was dependent on the p53 activity in the cell lines, but not on the expression of p53. Neither treatment with recombinant human Del-1 protein nor the introduction of adenovirus expressing Del-1 altered the expression of the apoptosis regulators BAX, PUMA and Bcl-2. Unexpectedly, the adenovirus-mediated overexpression of Del-1 gene into the lung carcinoma cell lines promoted proliferation and invasion of the lung carcinoma cells, as revealed by BrdU incorporation and transwell invasion assays, respectively. In addition, overexpression of the Del-1 gene enhanced features of epithelial–mesenchymal transition (EMT), such as increasing vimentin while decreasing E-cadherin in A549 cells, and increases in the level of Slug, an EMT-associated transcription regulator. Our findings demonstrated for the first time that there are deleterious effects of high levels of Del-1 in lung carcinoma cells, and suggest that Del-1 may be used as a diagnostic or prognostic marker for cancer progression, and as a novel therapeutic target for lung carcinoma. - Highlights: • Developmental Endothelial Locus-1 (Del-1) expression is downregulated in human lung cancer cells.

  4. Nuclear orphan receptor TLX affects gene expression, proliferation and cell apoptosis in beta cells.

    Science.gov (United States)

    Shi, Xiaoli; Xiong, Xiaokan; Dai, Zhe; Deng, Haohua; Sun, Li; Hu, Xuemei; Zhou, Feng; Xu, Yancheng

    Nuclear orphan receptor TLX is an essential regulator of the growth of neural stem cells. However, its exact function in pancreatic islet cells is still unknown. In the present study, gene expression profiling analysis revealed that overexpression of TLX in beta cell line MIN6 causes suppression of 176 genes and upregulation of 49 genes, including a cadre of cell cycle, cell proliferation and cell death control genes, such as Btg2, Ddit3 and Gadd45a. We next examined the effects of TLX overexpression on proliferation, apoptosis and insulin secretion in MIN6 cells. Proliferation analysis using EdU assay showed that overexpression of TLX increased percentage of EdU-positive cells. Cell cycle and apoptosis analysis revealed that overexpression of TLX in MIN6 cells resulted in higher percentage of cells exiting G1 into S-phase, and a 58.8% decrease of cell apoptosis induced by 0.5 mM palmitate. Moreover, TLX overexpression did not cause impairment of insulin secretion. Together, we conclude that TLX is among factors capable of controlling beta cell proliferation and survival, which may serve as a target for the development of novel therapies for diabetes. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Cell proliferation is necessary for the regeneration of oral structures in the anthozoan cnidarian Nematostella vectensis

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    Passamaneck Yale J

    2012-12-01

    Full Text Available Abstract Background The contribution of cell proliferation to regeneration varies greatly between different metazoan models. Planarians rely on pluripotent neoblasts and amphibian limb regeneration depends upon formation of a proliferative blastema, while regeneration in Hydra can occur in the absence of cell proliferation. Recently, the cnidarian Nematostella vectensis has shown potential as a model for studies of regeneration because of the ability to conduct comparative studies of patterning during embryonic development, asexual reproduction, and regeneration. The present study investigates the pattern of cell proliferation during the regeneration of oral structures and the role of cell proliferation in this process. Results In intact polyps, cell proliferation is observed in both ectodermal and endodermal tissues throughout the entire oral-aboral axis, including in the tentacles and physa. Following bisection, there is initially little change in proliferation at the wound site of the aboral fragment, however, beginning 18 to 24 hours after amputation there is a dramatic increase in cell proliferation at the wound site in the aboral fragment. This elevated level of proliferation is maintained throughout the course or regeneration of oral structures, including the tentacles, the mouth, and the pharynx. Treatments with the cell proliferation inhibitors hydroxyurea and nocodazole demonstrate that cell proliferation is indispensable for the regeneration of oral structures. Although inhibition of regeneration by nocodazole was generally irreversible, secondary amputation reinitiates cell proliferation and regeneration. Conclusions The study has found that high levels of cell proliferation characterize the regeneration of oral structures in Nematostella, and that this cell proliferation is necessary for the proper progression of regeneration. Thus, while cell proliferation contributes to regeneration of oral structures in both Nematostella and

  6. Adipose tissue-derived stem cells promote pancreatic cancer cell proliferation and invasion

    International Nuclear Information System (INIS)

    Ji, S.Q.; Cao, J.; Zhang, Q.Y.; Li, Y.Y.; Yan, Y.Q.; Yu, F.X.

    2013-01-01

    To explore the effects of adipose tissue-derived stem cells (ADSCs) on the proliferation and invasion of pancreatic cancer cells in vitro and the possible mechanism involved, ADSCs were cocultured with pancreatic cancer cells, and a cell counting kit (CCK-8) was used to detect the proliferation of pancreatic cancer cells. ELISA was used to determine the concentration of stromal cell-derived factor-1 (SDF-1) in the supernatants. RT-PCR was performed to detect the expression of the chemokine receptor CXCR4 in pancreatic cancer cells and ADSCs. An in vitro invasion assay was used to measure invasion of pancreatic cancer cells. SDF-1 was detected in the supernatants of ADSCs, but not in pancreatic cancer cells. Higher CXCR4 mRNA levels were detected in the pancreatic cancer cell lines compared with ADSCs (109.3±10.7 and 97.6±7.6 vs 18.3±1.7, respectively; P<0.01). In addition, conditioned medium from ADSCs promoted the proliferation and invasion of pancreatic cancer cells, and AMD3100, a CXCR4 antagonist, significantly downregulated these growth-promoting effects. We conclude that ADSCs can promote the proliferation and invasion of pancreatic cancer cells, which may involve the SDF-1/CXCR4 axis

  7. Adipose tissue-derived stem cells promote pancreatic cancer cell proliferation and invasion

    Energy Technology Data Exchange (ETDEWEB)

    Ji, S.Q.; Cao, J. [Department of Liver Surgery I, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai (China); Zhang, Q.Y.; Li, Y.Y. [Department of Hepatobiliary and Pancreatic Surgery, The First Affiliated Hospital, Wenzhou Medical College, Wenzhou (China); Yan, Y.Q. [Department of Liver Surgery I, Eastern Hepatobiliary Surgery Hospital, Second Military Medical University, Shanghai (China); Yu, F.X. [Department of Hepatobiliary and Pancreatic Surgery, The First Affiliated Hospital, Wenzhou Medical College, Wenzhou (China)

    2013-09-27

    To explore the effects of adipose tissue-derived stem cells (ADSCs) on the proliferation and invasion of pancreatic cancer cells in vitro and the possible mechanism involved, ADSCs were cocultured with pancreatic cancer cells, and a cell counting kit (CCK-8) was used to detect the proliferation of pancreatic cancer cells. ELISA was used to determine the concentration of stromal cell-derived factor-1 (SDF-1) in the supernatants. RT-PCR was performed to detect the expression of the chemokine receptor CXCR4 in pancreatic cancer cells and ADSCs. An in vitro invasion assay was used to measure invasion of pancreatic cancer cells. SDF-1 was detected in the supernatants of ADSCs, but not in pancreatic cancer cells. Higher CXCR4 mRNA levels were detected in the pancreatic cancer cell lines compared with ADSCs (109.3±10.7 and 97.6±7.6 vs 18.3±1.7, respectively; P<0.01). In addition, conditioned medium from ADSCs promoted the proliferation and invasion of pancreatic cancer cells, and AMD3100, a CXCR4 antagonist, significantly downregulated these growth-promoting effects. We conclude that ADSCs can promote the proliferation and invasion of pancreatic cancer cells, which may involve the SDF-1/CXCR4 axis.

  8. Proliferating cells in HIV and pamidronate-associated collapsing focal segmental glomerulosclerosis are parietal epithelial cells.

    NARCIS (Netherlands)

    Dijkman, H.B.P.M.; Weening, J.J.; Smeets, B.; Verrijp, K.; Kuppevelt, A.H.M.S.M. van; Assmann, K.K.; Steenbergen, E.; Wetzels, J.F.M.

    2006-01-01

    Collapsing focal segmental glomerulosclerosis (cFSGS) is characterized by hyperplasia of glomerular epithelial cells. In a mouse model of FSGS and in a patient with recurrent idiopathic FSGS, we identified the proliferating cells as parietal epithelial cells (PECs). In the present study, we have

  9. Proliferating cells in HIV and pamidronate-associated collapsing focal segmental glomerulosclerosis are parietal epithelial cells

    NARCIS (Netherlands)

    Dijkman, H. B. P. M.; Weening, J. J.; Smeets, B.; Verrijp, K. C. N.; van Kuppevelt, T. H.; Assmann, K. K. J. M.; Steenbergen, E. J.; Wetzels, J. F. M.

    2006-01-01

    Collapsing focal segmental glomerulosclerosis (cFSGS) is characterized by hyperplasia of glomerular epithelial cells. In a mouse model of FSGS and in a patient with recurrent idiopathic FSGS, we identified the proliferating cells as parietal epithelial cells (PECs). In the present study, we have

  10. Supporting Aspartate Biosynthesis Is an Essential Function of Respiration in Proliferating Cells.

    Science.gov (United States)

    Sullivan, Lucas B; Gui, Dan Y; Hosios, Aaron M; Bush, Lauren N; Freinkman, Elizaveta; Vander Heiden, Matthew G

    2015-07-30

    Mitochondrial respiration is important for cell proliferation; however, the specific metabolic requirements fulfilled by respiration to support proliferation have not been defined. Here, we show that a major role of respiration in proliferating cells is to provide electron acceptors for aspartate synthesis. This finding is consistent with the observation that cells lacking a functional respiratory chain are auxotrophic for pyruvate, which serves as an exogenous electron acceptor. Further, the pyruvate requirement can be fulfilled with an alternative electron acceptor, alpha-ketobutyrate, which provides cells neither carbon nor ATP. Alpha-ketobutyrate restores proliferation when respiration is inhibited, suggesting that an alternative electron acceptor can substitute for respiration to support proliferation. We find that electron acceptors are limiting for producing aspartate, and supplying aspartate enables proliferation of respiration deficient cells in the absence of exogenous electron acceptors. Together, these data argue a major function of respiration in proliferating cells is to support aspartate synthesis. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Retroviral-mediated transfer and expression of human β-globin genes in cultured murine and human erythroid cells

    International Nuclear Information System (INIS)

    Weber-Benarous, A.; Cone, R.D.; London, I.M.; Mulligan, R.C.

    1988-01-01

    The authors cloned human β-globin DNA sequences from a genomic library prepared from DNA isolated from the human leukemia cell line K562 and have used the retroviral vector pZip-NeoSV(X)1 to introduce a 3.0-kilobase segment encompassing the globin gene into mouse erythroleukemia cells. Whereas the endogenous K562 β-globin gene is repressed in K562 cells, when introduced into mouse erythroleukemia cells by retroviral-mediated gene transfer, the β-globin gene from K562 cells was transcribed and induced 5-20-fold after treatment of the cells with dimethyl sulfoxide. The transcripts were correctly initiated, and expression and regulation of the K562 gene were identical to the expression of a normal human β-globin gene transferred into mouse erythroleukemia cells in the same way. They have also introduced the normal human β-globin gene into K562 cells using the same retrovirus vector. SP6 analysis of the RNA isolated from the transduced cells showed that the normal β-globin gene was transcribed at a moderately high level, before or after treatment with hemin. Based on these data, they suggest that the lack of expression of the endogenous β-globin gene in K562 cells does not result from an alteration in the gene itself and may not result from a lack of factor(s) necessary for β-lobin gene transcription. Retroviral-mediated transfer of the human β-globin gene may, however, uniquely influence expression of the gene K562 cells

  12. mTOR-Dependent Cell Proliferation in the Brain

    Directory of Open Access Journals (Sweden)

    Larisa Ryskalin

    2017-01-01

    Full Text Available The mammalian Target of Rapamycin (mTOR is a molecular complex equipped with kinase activity which controls cell viability being key in the PI3K/PTEN/Akt pathway. mTOR acts by integrating a number of environmental stimuli to regulate cell growth, proliferation, autophagy, and protein synthesis. These effects are based on the modulation of different metabolic pathways. Upregulation of mTOR associates with various pathological conditions, such as obesity, neurodegeneration, and brain tumors. This is the case of high-grade gliomas with a high propensity to proliferation and tissue invasion. Glioblastoma Multiforme (GBM is a WHO grade IV malignant, aggressive, and lethal glioma. To date, a few treatments are available although the outcome of GBM patients remains poor. Experimental and pathological findings suggest that mTOR upregulation plays a major role in determining an aggressive phenotype, thus determining relapse and chemoresistance. Among several activities, mTOR-induced autophagy suppression is key in GBM malignancy. In this article, we discuss recent evidence about mTOR signaling and its role in normal brain development and pathological conditions, with a special emphasis on its role in GBM.

  13. mTOR-Dependent Cell Proliferation in the Brain.

    Science.gov (United States)

    Ryskalin, Larisa; Lazzeri, Gloria; Flaibani, Marina; Biagioni, Francesca; Gambardella, Stefano; Frati, Alessandro; Fornai, Francesco

    2017-01-01

    The mammalian Target of Rapamycin (mTOR) is a molecular complex equipped with kinase activity which controls cell viability being key in the PI3K/PTEN/Akt pathway. mTOR acts by integrating a number of environmental stimuli to regulate cell growth, proliferation, autophagy, and protein synthesis. These effects are based on the modulation of different metabolic pathways. Upregulation of mTOR associates with various pathological conditions, such as obesity, neurodegeneration, and brain tumors. This is the case of high-grade gliomas with a high propensity to proliferation and tissue invasion. Glioblastoma Multiforme (GBM) is a WHO grade IV malignant, aggressive, and lethal glioma. To date, a few treatments are available although the outcome of GBM patients remains poor. Experimental and pathological findings suggest that mTOR upregulation plays a major role in determining an aggressive phenotype, thus determining relapse and chemoresistance. Among several activities, mTOR-induced autophagy suppression is key in GBM malignancy. In this article, we discuss recent evidence about mTOR signaling and its role in normal brain development and pathological conditions, with a special emphasis on its role in GBM.

  14. Clonal variation in proliferation rate of cultures of GPK cells.

    Science.gov (United States)

    Riley, P A; Hola, M

    1981-09-01

    Pedigrees of twenty-six clones of a line of keratocytes derived from guinea-pig ear epidermis (GPK cells) were analysed from time-lapse film. The mean interdivision time (IDT) for the culture was 1143 +/- 215 (SD) min. The mean generation rates (mean reciprocal interdivision times) of clones varied over a range of 3.93--10.2 x 10(-4)/min and the standard deviation of the clonal mean generation rates was 16.8% of the average value. Transient intraclonal variations in IDT due to mitoses in a plane perpendicular to the substratum were observed. The data were also analysed on the basis of cell location in sixteen equal zones (quadrats) of the filmed area. The mean generation rate of quadrats was 8.73 x 10(-4)/min (SD = 4.9%). The spatial distribution showed some clustering of cells. The mean local density of the clones (2.25 +/- 0.62 cells/10(-4) cm2) was significantly higher than the quadrat density (1.76 +/- 0.8 cells/10(-4) cm2). There was no significant correlation between clonal density and mean generation rates, whereas for quadrats a significant negative correlation was found (P = 2.7%). The results support the proposition that cell lineage is the major determinant of the proliferation rate of subconfluent cultures.

  15. Cell proliferation along vascular islands during microvascular network growth

    Directory of Open Access Journals (Sweden)

    Kelly-Goss Molly R

    2012-06-01

    Full Text Available Abstract Background Observations in our laboratory provide evidence of vascular islands, defined as disconnected endothelial cell segments, in the adult microcirculation. The objective of this study was to determine if vascular islands are involved in angiogenesis during microvascular network growth. Results Mesenteric tissues, which allow visualization of entire microvascular networks at a single cell level, were harvested from unstimulated adult male Wistar rats and Wistar rats 3 and 10 days post angiogenesis stimulation by mast cell degranulation with compound 48/80. Tissues were immunolabeled for PECAM and BRDU. Identification of vessel lumens via injection of FITC-dextran confirmed that endothelial cell segments were disconnected from nearby patent networks. Stimulated networks displayed increases in vascular area, length density, and capillary sprouting. On day 3, the percentage of islands with at least one BRDU-positive cell increased compared to the unstimulated level and was equal to the percentage of capillary sprouts with at least one BRDU-positive cell. At day 10, the number of vascular islands per vascular area dramatically decreased compared to unstimulated and day 3 levels. Conclusions These results show that vascular islands have the ability to proliferate and suggest that they are able to incorporate into the microcirculation during the initial stages of microvascular network growth.

  16. Maslinic acid inhibits proliferation of renal cell carcinoma cell lines and suppresses angiogenesis of endothelial cells

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    Parth Thakor

    2017-03-01

    Full Text Available Despite the introduction of many novel therapeutics in clinical practice, metastatic renal cell carcinoma (RCC remains a treatment-re-sistant cancer. As red and processed meat are considered risk factors for RCC, and a vegetable-rich diet is thought to reduce this risk, research into plant-based therapeutics may provide valuable complementary or alternative therapeutics for the management of RCC. Herein, we present the antiproliferative and antiangiogenic effects of maslinic acid, which occurs naturally in edible plants, particularly in olive fruits, and also in a variety of medicinal plants. Human RCC cell lines (ACHN, Caki-1, and SN12K1, endothelial cells (human umbilical vein endothelial cell line [HUVEC], and primary cultures of kidney proximal tubular epithelial cells (PTEC were treated with maslinic acid. Maslinic acid was relatively less toxic to PTEC when compared with RCC under similar experimental conditions. In RCC cell lines, maslinic acid induced a significant reduction in proliferation, proliferating cell nuclear antigen, and colony formation. In HUVEC, maslinic acid induced a significant reduction in capillary tube formation in vitro and vascular endothelial growth factor. This study provides a rationale for incorporating a maslinic acid–rich diet either to reduce the risk of developing kidney cancer or as an adjunct to existing antiangiogenic therapy to improve efficacy.

  17. NSA2, a novel nucleolus protein regulates cell proliferation and cell cycle

    International Nuclear Information System (INIS)

    Zhang, Heyu; Ma, Xi; Shi, Taiping; Song, Quansheng; Zhao, Hongshan; Ma, Dalong

    2010-01-01

    NSA2 (Nop seven-associated 2) was previously identified in a high throughput screen of novel human genes associated with cell proliferation, and the NSA2 protein is evolutionarily conserved across different species. In this study, we revealed that NSA2 is broadly expressed in human tissues and cultured cell lines, and located in the nucleolus of the cell. Both of the putative nuclear localization signals (NLSs) of NSA2, also overlapped with nucleolar localization signals (NoLSs), are capable of directing nucleolar accumulation. Moreover, over-expression of the NSA2 protein promoted cell growth in different cell lines and regulated the G1/S transition in the cell cycle. SiRNA silencing of the NSA2 transcript attenuated the cell growth and dramatically blocked the cell cycle in G1/S transition. Our results demonstrated that NSA2 is a nucleolar protein involved in cell proliferation and cell cycle regulation.

  18. [Inhibition effects of black rice pericarp extracts on cell proliferation of PC-3 cells].

    Science.gov (United States)

    Jiang, Weiwei; Yu, Xudong; Ren, Guofeng

    2013-05-01

    To observe the inhibitive effects of black rice pericarp extracts on cell proliferation of human prostate cancer cell PC-3 and to explore its effecting mechanism. The black rice pericarp extract was used to treat the PC-3 cells. The inhibitory effect of black rice pericarp extract on cells proliferation of PC-3 was tested by MTT method. Cell apoptosis rates and cell cycle were measured by flow cytometric assay (FCM). Western blot was used to study the protein expression levels of p38, p-p38, JNK, p-JNK. A dose-dependent and time-dependent proliferation inhibition of black rice pericarp extract was demonstrated in PC-3. The most prominent experiment condition was inhibitory concentration with 300microg/ml and treated for 72 h. The experiment result of flow cytometry analysis demonstrates that the apoptosis rate of PC-3 cells increased along with the increasing of black rice pericarp extract concentration, and a G1-S cell cycle arrest was induced in a dose-dependent manner. After PC-3 cell was treated with black rice pericarp extract for 72 h, the expressions of p-p38, p-JNK protein increased. Black rice pericarp extract could inhibit proliferation, change the cell cycle distributions and induce apoptosis in human prostatic cancer cell PC-3. Its inhibitory effect may be through promoting activation of the JNK, p38 signaling pathway. These results suggest that black rice pericarp extract maybe has an inhibitory effect on prostatic cancer.

  19. Effects on proliferation and cell cycle of irradiated KG-1 cells stimulated by CM-CSF

    International Nuclear Information System (INIS)

    Guo Dehuang; Dong Bo; Wen Gengyun; Luo Qingliang; Mao Bingzhi

    2000-01-01

    In order to explore the variety of cell proliferation and cell cycle after exposure to ionizing radiation, the responses of irradiated KG-1 cells of the human myeloid leukemia stimulated by GM-CSF, the most common used cytokine in clinic, were investigated. The results showed that GM-CSF enhance KG-1 cells proliferation, reduce G0/G1 block, increase S phase and G2/M phase. The stimulation effects of the GM-CSF are more effective in irradiated group than in control group

  20. Distinct Dasatinib-Induced Mechanisms of Apoptotic Response and Exosome Release in Imatinib-Resistant Human Chronic Myeloid Leukemia Cells

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    Juan Liu

    2016-04-01

    Full Text Available Although dasatinib is effective in most imatinib mesylate (IMT-resistant chronic myeloid leukemia (CML patients, the underlying mechanism of its effectiveness in eliminating imatinib-resistant cells is only partially understood. This study investigated the effects of dasatinib on signaling mechanisms driving-resistance in imatinib-resistant CML cell line K562 (K562RIMT. Compared with K562 control cells, exsomal release, the phosphoinositide 3-kinase (PI3K/protein kinase B (Akt/ mammalian target of rapamycin (mTOR signaling and autophagic activity were increased significantly in K562RIMT cells and mTOR-independent beclin-1/Vps34 signaling was shown to be involved in exosomal release in these cells. We found that Notch1 activation-mediated reduction of phosphatase and tensin homolog (PTEN was responsible for the increased Akt/mTOR activities in K562RIMT cells and treatment with Notch1 γ-secretase inhibitor prevented activation of Akt/mTOR. In addition, suppression of mTOR activity by rapamycin decreased the level of activity of p70S6K, induced upregulation of p53 and caspase 3, and led to increase of apoptosis in K562RIMT cells. Inhibition of autophagy by spautin-1 or beclin-1 knockdown decreased exosomal release, but did not affect apoptosis in K562RIMT cells. In summary, in K562RIMT cells dasatinib promoted apoptosis through downregulation of Akt/mTOR activities, while preventing exosomal release and inhibiting autophagy by downregulating expression of beclin-1 and Vps34. Our findings reveal distinct dasatinib-induced mechanisms of apoptotic response and exosomal release in imatinib-resistant CML cells.

  1. Indirubin inhibits cell proliferation, migration, invasion and angiogenesis in tumor-derived endothelial cells

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    Li Z

    2018-05-01

    Full Text Available Zhuohong Li, Chaofu Zhu, Baiping An, Yu Chen, Xiuyun He, Lin Qian, Lan Lan, Shijie Li Department of Oncology, The Affiliated Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China Purpose: Hepatocellular carcinoma is one of the most predominant malignancies with high fatality rate and its incidence is rising at an alarming rate because of its resistance to radio- and chemotherapy. Indirubin is the major active anti-tumor ingredient of a traditional Chinese herbal medicine. The present study aimed to analyze the effects of indirubin on cell proliferation, migration, invasion, and angiogenesis of tumor-derived endothelial cells (Td-EC. Methods: Td-EC were derived from human umbilical vein endothelial cells (HUVEC by treating HUVEC with the conditioned medium of human liver cancer cell line HepG2. Cell proliferation, migration, invasion, and angiogenesis were assessed by MTT, wound healing, in vitro cell invasion, and in vitro tube formation assay. Results: Td-EC were successfully obtained from HUVEC cultured with 50% culture supernatant from serum-starved HepG2 cells. Indirubin significantly inhibited Td-EC proliferation in a dose- and time-dependent manner. Indirubin also inhibited Td-EC migration, invasion, and angiogenesis. However, indirubin’s effects were weaker on HUVEC than Td-EC. Conclusion: Indirubin significantly inhibited Td-EC proliferation, migration, invasion, and angiogenesis. Keywords: indirubin, Td-EC, proliferation, migration, invasion, angiogenesis

  2. Functional interrelationship between TFII-I and E2F transcription factors at specific cell cycle gene loci.

    Science.gov (United States)

    Shen, Yong; Nar, Rukiye; Fan, Alex X; Aryan, Mahmoud; Hossain, Mir A; Gurumurthy, Aishwarya; Wassel, Paul C; Tang, Ming; Lu, Jianrong; Strouboulis, John; Bungert, Jörg

    2018-01-01

    Transcription factor TFII-I is a multifunctional protein implicated in the regulation of cell cycle and stress-response genes. Previous studies have shown that a subset of TFII-I associated genomic sites contained DNA-binding motifs for E2F family transcription factors. We analyzed the co-association of TFII-I and E2Fs in more detail using bioinformatics, chromatin immunoprecipitation, and co-immunoprecipitation experiments. The data show that TFII-I interacts with E2F transcription factors. Furthermore, TFII-I, E2F4, and E2F6 interact with DNA-regulatory elements of several genes implicated in the regulation of the cell cycle, including DNMT1, HDAC1, CDKN1C, and CDC27. Inhibition of TFII-I expression led to a decrease in gene expression and in the association of E2F4 and E2F6 with these gene loci in human erythroleukemia K562 cells. Finally, TFII-I deficiency reduced the proliferation of K562 cells and increased the sensitivity toward doxorubicin toxicity. The results uncover novel interactions between TFII-I and E2Fs and suggest that TFII-I mediates E2F function at specific cell cycle genes. © 2017 Wiley Periodicals, Inc.

  3. Dictyostelium cells bind a secreted autocrine factor that represses cell proliferation

    Directory of Open Access Journals (Sweden)

    Phillips Jonathan E

    2009-02-01

    Full Text Available Abstract Background Dictyostelium cells secrete the proteins AprA and CfaD. Cells lacking either AprA or CfaD proliferate faster than wild type, while AprA or CfaD overexpressor cells proliferate slowly, indicating that AprA and CfaD are autocrine factors that repress proliferation. CfaD interacts with AprA and requires the presence of AprA to slow proliferation. To determine if CfaD is necessary for the ability of AprA to slow proliferation, whether AprA binds to cells, and if so whether the binding requires the presence of CfaD, we examined the binding and effect on proliferation of recombinant AprA. Results We find that the extracellular accumulation of AprA increases with cell density and reaches a concentration of 0.3 μg/ml near a stationary cell density. When added to wild-type or aprA- cells, recombinant AprA (rAprA significantly slows proliferation at 0.1 μg/ml and higher concentrations. From 4 to 64 μg/ml, the effect of rAprA is at a plateau, slowing but not stopping proliferation. The proliferation-inhibiting activity of rAprA is roughly the same as that of native AprA in conditioned growth medium. Proliferating aprA- cells show saturable binding of rAprA to 92,000 ± 11,000 cell-surface receptors with a KD of 0.03 ± 0.02 μg/ml. There appears to be one class of binding site, and no apparent cooperativity. Native AprA inhibits the binding of rAprA to aprA- cells with a Ki of 0.03 μg/ml, suggesting that the binding kinetics of rAprA are similar to those of native AprA. The proliferation of cells lacking CrlA, a cAMP receptor-like protein, or cells lacking CfaD are not affected by rAprA. Surprisingly, both cell types still bind rAprA. Conclusion Together, the data suggest that AprA functions as an autocrine proliferation-inhibiting factor by binding to cell surface receptors. Although AprA requires CfaD for activity, it does not require CfaD to bind to cells, suggesting the possibility that cells have an AprA receptor and a Cfa

  4. Dictyostelium cells bind a secreted autocrine factor that represses cell proliferation.

    Science.gov (United States)

    Choe, Jonathan M; Bakthavatsalam, Deenadayalan; Phillips, Jonathan E; Gomer, Richard H

    2009-02-02

    Dictyostelium cells secrete the proteins AprA and CfaD. Cells lacking either AprA or CfaD proliferate faster than wild type, while AprA or CfaD overexpressor cells proliferate slowly, indicating that AprA and CfaD are autocrine factors that repress proliferation. CfaD interacts with AprA and requires the presence of AprA to slow proliferation. To determine if CfaD is necessary for the ability of AprA to slow proliferation, whether AprA binds to cells, and if so whether the binding requires the presence of CfaD, we examined the binding and effect on proliferation of recombinant AprA. We find that the extracellular accumulation of AprA increases with cell density and reaches a concentration of 0.3 microg/ml near a stationary cell density. When added to wild-type or aprA- cells, recombinant AprA (rAprA) significantly slows proliferation at 0.1 microg/ml and higher concentrations. From 4 to 64 microg/ml, the effect of rAprA is at a plateau, slowing but not stopping proliferation. The proliferation-inhibiting activity of rAprA is roughly the same as that of native AprA in conditioned growth medium. Proliferating aprA- cells show saturable binding of rAprA to 92,000 +/- 11,000 cell-surface receptors with a KD of 0.03 +/- 0.02 microg/ml. There appears to be one class of binding site, and no apparent cooperativity. Native AprA inhibits the binding of rAprA to aprA- cells with a Ki of 0.03 mug/ml, suggesting that the binding kinetics of rAprA are similar to those of native AprA. The proliferation of cells lacking CrlA, a cAMP receptor-like protein, or cells lacking CfaD are not affected by rAprA. Surprisingly, both cell types still bind rAprA. Together, the data suggest that AprA functions as an autocrine proliferation-inhibiting factor by binding to cell surface receptors. Although AprA requires CfaD for activity, it does not require CfaD to bind to cells, suggesting the possibility that cells have an AprA receptor and a CfaD receptor, and activation of both receptors is

  5. Cell proliferation changes in hemopoietic tissue as a result of irradiation or drug administration: the control of cell proliferation in hemopoietic tissue

    International Nuclear Information System (INIS)

    Lord, B.I.

    1975-01-01

    The nature of the control processes operative on these cells is not completely understood. Erythropoietin has long been known as a direct stimulator of erythropoiesis at all levels. A similar compound has long been sought (unsuccessfully) to stimulate granulopoiesis. Currently the role of specific proliferation inhibitors of erythropoiesis and granulopoiesis are now attaining more prominence. In this respect, Patt and Maloney demonstrated an inverse relationship of cell concentration in the rabbit femur and the uptake of tritiated thymidine by the cells, and we have now established that extracts of mature blood cells do have specific effects on developing hemopoietic cells which are compatible with proliferation inhibition and which are completely reversible. Our current studies are showing that, used in vivo, these extracts are in fact capable of lowering the proliferation rates of the maturing hemopoietic cells (Lord- unpublished results). It is clear, therefore, that the maturing cell populations proliferate under a complex set of control processes

  6. Orphan nuclear receptor TLX recruits histone deacetylases to repress transcription and regulate neural stem cell proliferation

    OpenAIRE

    Sun, GuoQiang; Yu, Ruth T.; Evans, Ronald M.; Shi, Yanhong

    2007-01-01

    TLX is a transcription factor that is essential for neural stem cell proliferation and self-renewal. However, the molecular mechanism of TLX-mediated neural stem cell proliferation and self-renewal is largely unknown. We show here that TLX recruits histone deacetylases (HDACs) to its downstream target genes to repress their transcription, which in turn regulates neural stem cell proliferation. TLX interacts with HDAC3 and HDAC5 in neural stem cells. The HDAC5-interaction domain was mapped to ...

  7. Nuclear location of tumor suppressor protein maspin inhibits proliferation of breast cancer cells without affecting proliferation of normal epithelial cells

    International Nuclear Information System (INIS)

    Machowska, Magdalena; Wachowicz, Katarzyna; Sopel, Mirosław; Rzepecki, Ryszard

    2014-01-01

    Maspin, which is classified as a tumor suppressor protein, is downregulated in many types of cancer. Several studies have suggested potential anti-proliferative activity of maspin as well as sensitizing activity of maspin for therapeutic cytotoxic agents in breast cancer tissue culture and animal models. All of the experimental data gathered so far have been based on studies with maspin localized cytoplasmically, while maspin in breast cancer tumor cells may be located in the cytoplasm, nucleus or both. In this study, the effect of maspin cytoplasmic and nuclear location and expression level on breast cancer proliferation and patient survival was studied. Tissue sections from 166 patients with invasive ductal breast cancer were stained by immunohistochemistry for maspin and Ki-67 protein. The localization and expression level of maspin were correlated with estimated patient overall survival and percent of Ki-67-positive cells. In further studies, we created constructs for transient transfection of maspin into breast cancer cells with targeted cytoplasmic and nuclear location. We analyzed the effect of maspin location in normal epithelial cell line MCF10A and three breast cancer cell lines - MCF-7, MDA-MB-231 and SKBR-3 - by immunofluorescence and proliferation assay. We observed a strong positive correlation between moderate and high nuclear maspin level and survival of patients. Moreover, a statistically significant negative relationship was observed between nuclear maspin and Ki-67 expression in patients with invasive ductal breast cancer. Spearman’s correlation analysis showed a negative correlation between level of maspin localized in nucleus and percentage of Ki-67 positive cells. No such differences were observed in cells with cytoplasmic maspin. We found a strong correlation between nuclear maspin and loss of Ki-67 protein in breast cancer cell lines, while there was no effect in normal epithelial cells from breast. The anti-proliferative effect of nuclear

  8. Nuclear location of tumor suppressor protein maspin inhibits proliferation of breast cancer cells without affecting proliferation of normal epithelial cells

    Science.gov (United States)

    2014-01-01

    Background Maspin, which is classified as a tumor suppressor protein, is downregulated in many types of cancer. Several studies have suggested potential anti-proliferative activity of maspin as well as sensitizing activity of maspin for therapeutic cytotoxic agents in breast cancer tissue culture and animal models. All of the experimental data gathered so far have been based on studies with maspin localized cytoplasmically, while maspin in breast cancer tumor cells may be located in the cytoplasm, nucleus or both. In this study, the effect of maspin cytoplasmic and nuclear location and expression level on breast cancer proliferation and patient survival was studied. Methods Tissue sections from 166 patients with invasive ductal breast cancer were stained by immunohistochemistry for maspin and Ki-67 protein. The localization and expression level of maspin were correlated with estimated patient overall survival and percent of Ki-67-positive cells. In further studies, we created constructs for transient transfection of maspin into breast cancer cells with targeted cytoplasmic and nuclear location. We analyzed the effect of maspin location in normal epithelial cell line MCF10A and three breast cancer cell lines - MCF-7, MDA-MB-231 and SKBR-3 - by immunofluorescence and proliferation assay. Results We observed a strong positive correlation between moderate and high nuclear maspin level and survival of patients. Moreover, a statistically significant negative relationship was observed between nuclear maspin and Ki-67 expression in patients with invasive ductal breast cancer. Spearman’s correlation analysis showed a negative correlation between level of maspin localized in nucleus and percentage of Ki-67 positive cells. No such differences were observed in cells with cytoplasmic maspin. We found a strong correlation between nuclear maspin and loss of Ki-67 protein in breast cancer cell lines, while there was no effect in normal epithelial cells from breast. The anti

  9. [Notochord cells enhance proliferation and phenotype-keeping of intervertebral disc chondroid cells].

    Science.gov (United States)

    Zhao, Xianfeng; Liu, Hao; Feng, Ganjun; Deng, Li; Li, Xiuqun; Liang, Tao

    2008-08-01

    To isolate and culture the chondroid cells and notochord cells from New Zealand rabbit immature nucleus pulposus (NP) in monolayer, and to evaluate the responsiveness of rabbit disc-derived chondroid cells to notochord cells with respect to cell proliferation and phenotype. The NP cells were released from the minced immature NP of 6 New Zealand rabbits (4-week-old) by 0.2% collagenase II digestion. The chondroid cells and notochord cells were purified by discontinuous gradient density centrifugation. The chondroid cells were cultured alone (group A) and co-cultured with notochord cells (group B) (1:1), and cell proliferation and phenotype including proteoglycan and collagen II were evaluated. The cells in both groups were observed by the inverted microscope, and the survival rates of the primary and passage cells were detected by toluidine blue staining. The growth curves of the second passage cells in both groups were determined by MTT. Besides, the expressions of proteoglycan and collagen II of the primary and passage cells were examined by toluidine blue and immunocytochemistry staining. The notochord cells and chondroid cells were isolated and purified. With the diameter of 10-15 microm, the notochord cell had abundant intracytoplasmic vesicles, while the chondroid cell, with the diameter of 4-6 microm, had no intracytoplasmic vesicle. The cell survival rate was 89.0%-95.3% in group A and 91.3%-96.3% in group B. There was no significant difference between the same passages in both groups (P > 0.05). The co-cultured cells (group B) increased in cell proliferation compared with the chondroid cells alone (group A) in repeated experiments. The cells in group A reached their logarithmic growth phase after 3-4 days of culture, while the cells in group B did after 2 days of culture. The cell proliferation in group B was more than that in group A after 4-day culture (P notochord cells are conducive for the proliferation and phenotype-keeping of the chondroid cells and

  10. Leading research on cell proliferation regulation technology; Saibo zoshoku seigyo gijutsu no sendo kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    For developing intelligent material, animal test alternative model, bio-cell analysis equipment, self-controlling bio-reactor and medical material, development of functional cells was studied by cell proliferation regulation technology. In fiscal 1996, the expression analysis and separation technology of specific gene for cell proliferation, and the intracellular regulation technology were surveyed from the viewpoint of intracellular regulation. The cell proliferation regulation technology by specific regulating material of cells, extracellular matrix, coculture system and embryonic cell was surveyed from the viewpoint of extracellular regulation. In addition, based on these survey results, new cell culture/analysis technology, new bio-material, artificial organ system, energy saving bio-reactor, environment purification microorganism, and animal test alternative model were surveyed as applications to industrial basic technologies from a long-term viewpoint. The approach to cell proliferation regulation requires preparation of a concrete proliferation regulation technology system of cells, and concrete application targets. 268 refs., 43 figs., 4 tabs.

  11. Psoriatic T cells reduce epidermal turnover time and affect cell proliferation contributed from differential gene expression.

    Science.gov (United States)

    Li, Junqin; Li, Xinhua; Hou, Ruixia; Liu, Ruifeng; Zhao, Xincheng; Dong, Feng; Wang, Chunfang; Yin, Guohua; Zhang, Kaiming

    2015-09-01

    Psoriasis is mediated primarily by T cells, which reduce epidermal turnover time and affect keratinocyte proliferation. We aimed to identify differentially expressed genes (DEG) in T cells from normal, five pairs of monozygotic twins concordant or discordant for psoriasis, to determine whether these DEG may account for the influence to epidermal turnover time and keratinocyte proliferation. The impact of T cells on keratinocyte proliferation and epidermal turnover time were investigated separately by immunohistochemistry and cultured with (3) H-TdR. mRNA expression patterns were investigated by RNA sequencing and verified by real-time reverse transcription polymerase chain reaction. After co-culture with psoriatic T cells, the expression of Ki-67, c-Myc and p53 increased, while expression of Bcl-2 and epidermal turnover time decreased. There were 14 DEG which were found to participate in the regulation of cell proliferation or differentiation. Psoriatic T cells exhibited the ability to decrease epidermal turnover time and affect keratinocyte proliferation because of the differential expression of PPIL1, HSPH1, SENP3, NUP54, FABP5, PLEKHG3, SLC9A9 and CHCHD4. © 2015 Japanese Dermatological Association.

  12. Hepatocellular proliferation in response to agonists of peroxisome proliferator-activated receptor alpha: a role for kupffer cells?

    Directory of Open Access Journals (Sweden)

    Cunningham Michael

    2006-01-01

    Full Text Available Abstract Background It has been proposed that PPARα agonists stimulate Kupffer cells in rodents which in turn, release mitogenic factors leading to hepatic hyperplasia, and eventually cancer. However, Kupffer cells do not express PPARα receptors, and PPARα agonists stimulate hepatocellular proliferation in both TNFα- and TNFα receptor-null mice, casting doubt on the involvement of Kupffer cells in the mitogenic response to PPARα agonists. This study was therefore designed to investigate whether the PPARα agonist PFOA and the Kupffer cell inhibitor methylpalmitate produce opposing effects on hepatocellular proliferation and Kupffer cell activity in vivo, in a manner that would implicate these cells in the mitogenic effects of PPARα agonists. Methods Male Sprague-Dawley rats were treated intravenously via the tail vein with methylpalmitate 24 hrs prior to perfluorooctanoic acid (PFOA, and were sacrificed 24 hrs later, one hr after an intraperitoneal injection of bromodeoxyuridine (BrdU. Sera were analyzed for TNFα and IL-1β. Liver sections were stained immunohistochemically and quantified for BrdU incorporated into DNA. Results Data show that PFOA remarkably stimulated hepatocellular proliferation in the absence of significant changes in the serum levels of either TNFα or IL-1β. In addition, methylpalmitate did not alter the levels of these mitogens in PFOA-treated animals, despite the fact that it significantly blocked the hepatocellular proliferative effect of PFOA. Correlation between hepatocellular proliferation and serum levels of TNFα or IL-1β was extremely poor. Conclusion It is unlikely that mechanisms involving Kupffer cells play an eminent role in the hepatic hyperplasia, and consequently hepatocarcinogenicity attributed to PPARα agonists. This conclusion is based on the above mentioned published data and the current findings showing animals treated with PFOA alone or in combination with methylpalmitate to have similar

  13. [Regulatory T cells inhibit proliferation of mouse lymphoma cell line EL4 in vitro].

    Science.gov (United States)

    Zhang, Chen; Kong, Yan; Guo, Jun; Ying, Zhi-Tao; Yuan, Zhi-Hong; Zhang, Yun-Tao; Zheng, Wen; Song, Yu-Qin; Li, Ping-Ping; Zhu, Jun

    2010-10-01

    This study was aimed to investigate the effect of regulatory T (Treg) cells on the T cell lymphoma EL4 cells and its mechanism in vitro. C57BL/6 mouse Treg cells were isolated by magnetic cell sorting (MACS). The purity of Treg cells and their expression of Foxp3 were identified by flow cytometry (FCM) and PT-PCR respectively. The suppression of Treg cells on EL4 cells was detected by 3H-TdR method. At the same time, enzyme-linked immunosorbent assay (ELISA) was used to detect the secretion of cytokine TGF-β1 and IL-10. The results showed that CD4+CD25+ T cells could be successfully isolated by MACS with the purity reaching 94.52% and the expression of Foxp3 reaching 84.72%. After sorting, the expression of Foxp3 mRNA could be detected by RT-PCR. 3H-TdR assay confirmed that regulatory T cells could suppress the proliferation of EL4 cells with or without antigen presenting cells (APC) or dendritic cells (DC), APC or DC might effectively enhance the suppression. In addition, DC alone also suppressed the proliferation. TGF-β1 and IL-10 could be detected in the supernatant by ELISA. It is concluded that the Treg cells can obviously suppress the proliferation of T cell lymphoma cells in vitro, APC or DC can enhance this suppressive effect, while the DC alone also can suppress the proliferation of EL4 cells, the TGF-β1 and IL-10 cytokine pathway may be one of the mechanisms of suppression.

  14. The nucleolus: a paradigm for cell proliferation and aging

    Directory of Open Access Journals (Sweden)

    Comai L.

    1999-01-01

    Full Text Available The nucleolus is the cellular site of ribosome biosynthesis. At this site, active ribosomal DNA (rDNA genes are rapidly transcribed by RNA polymerase I (pol I molecules. Recent advances in our understanding of the pol I transcription system have indicated that regulation of ribosomal RNA (rRNA synthesis is a critical factor in cell growth. Importantly, the same signaling networks that control cell growth and proliferation and are deregulated in cancer appear to control pol I transcription. Therefore, the study of the biochemical basis for growth regulation of pol I transcription can provide basic information about the nuclear signaling network. Hopefully, this information may facilitate the search for drugs that can inhibit the growth of tumor cells by blocking pol I activation. In addition to its function in ribosome biogenesis, recent studies have revealed the prominent role of the nucleolus in cell senescence. These findings have stimulated a new wave of research on the functional relationship between the nucleolus and aging. The aim of this review is to provide an overview of some current topics in the area of nucleolus biology, and it has been written for a general readership.

  15. A novel splice variant of supervillin, SV5, promotes carcinoma cell proliferation and cell migration

    International Nuclear Information System (INIS)

    Chen, Xueran; Yang, Haoran; Zhang, Shangrong; Wang, Zhen; Ye, Fang; Liang, Chaozhao; Wang, Hongzhi; Fang, Zhiyou

    2017-01-01

    Supervillin is an actin-associated protein that regulates actin dynamics by interacting with Myosin II, F-actin, and Cortactin to promote cell contractility and cell motility. Two splicing variants of human Supervillin (SV1 and SV4) have been reported in non-muscle cells; SV1 lacks 3 exons present in the larger isoform SV4. SV2, also called archvillin, is present in striated muscle; SV3, also called smooth muscle archvillin or SmAV, was cloned from smooth muscle. In the present study, we identify a novel splicing variant of Supervillin (SV5). SV5 contains a new splicing pattern. In the mouse tissues and cell lines examined, SV5 was predominantly expressed in skeletal and cardiac muscles and in proliferating cells, but was virtually undetectable in most normal tissues. Using RNAi and rescue experiments, we show here that SV5 displays altered functional properties in cancer cells, and regulates cell proliferation and cell migration.

  16. Protease-activated receptor 2 modulates proliferation and invasion of oral squamous cell carcinoma cells.

    Science.gov (United States)

    Al-Eryani, Kamal; Cheng, Jun; Abé, Tatsuya; Maruyama, Satoshi; Yamazaki, Manabu; Babkair, Hamzah; Essa, Ahmed; Saku, Takashi

    2015-07-01

    Based on our previous finding that protease-activated receptor 2 (PAR-2) regulates hemophagocytosis of oral squamous cell carcinoma (SCC) cells, which induces their heme oxygenase 1-dependent keratinization, we have formulated a hypothesis that PAR-2 functions in wider activities of SCC cells. To confirm this hypothesis, we investigated immunohistochemical profiles of PAR-2 in oral SCC tissues and its functional roles in cell proliferation and invasion in SCC cells in culture. The PAR-2 expression modes were determined in 48 surgical tissue specimens of oral SCC. Using oral SCC-derived cell systems, we determined both gene and protein expression levels of PAR-2. SCC cell proliferation and invasive properties were also examined in conditions in which PAR-2 was activated by the synthetic peptide SLIGRL. PAR-2 was immunolocalized in oral SCC and carcinoma in situ cells, especially in those on the periphery of carcinoma cell foci (100% of cases), but not in normal oral epithelia. Its expression at both gene and protein levels was confirmed in 3 oral SCC cell lines including ZK-1. Activation of PAR-2 induced ZK-1 cell proliferation in a dose-dependent manner. PAR-2-activated ZK-1 cells invaded faster than nonactivated ones. The expression of PAR-2 is specific to oral malignancies, and PAR-2 regulates the growth and invasion of oral SCC cells. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Transient inhibition of cell proliferation does not compromise self-renewal of mouse embryonic stem cells.

    Science.gov (United States)

    Wang, Ruoxing; Guo, Yan-Lin

    2012-10-01

    Embryonic stem cells (ESCs) have unlimited capacity for self-renewal and can differentiate into various cell types when induced. They also have an unusual cell cycle control mechanism driven by constitutively active cyclin dependent kinases (Cdks). In mouse ESCs (mESCs). It is proposed that the rapid cell proliferation could be a necessary part of mechanisms that maintain mESC self-renewal and pluripotency, but this hypothesis is not in line with the finding in human ESCs (hESCs) that the length of the cell cycle is similar to differentiated cells. Therefore, whether rapid cell proliferation is essential for the maintenance of mESC state remains unclear. We provide insight into this uncertainty through chemical intervention of mESC cell cycle. We report here that inhibition of Cdks with olomoucine II can dramatically slow down cell proliferation of mESCs with concurrent down-regulation of cyclin A, B and E, and the activation of the Rb pathway. However, mESCs display can recover upon the removal of olomoucine II and are able to resume normal cell proliferation without losing self-renewal and pluripotency, as demonstrated by the expression of ESC markers, colony formation, embryoid body formation, and induced differentiation. We provide a mechanistic explanation for these observations by demonstrating that Oct4 and Nanog, two major transcription factors that play critical roles in the maintenance of ESC properties, are up-regulated via de novo protein synthesis when the cells are exposed to olomoucine II. Together, our data suggest that short-term inhibition of cell proliferation does not compromise the basic properties of mESCs. Copyright © 2012 Elsevier Inc. All rights reserved.

  18. Gallic acid reduces cell viability, proliferation, invasion and angiogenesis in human cervical cancer cells

    OpenAIRE

    ZHAO, BING; HU, MENGCAI

    2013-01-01

    Gallic acid is a trihydroxybenzoic acid, also known as 3,4,5-trihydroxybenzoic acid, which is present in plants worldwide, including Chinese medicinal herbs. Gallic acid has been shown to have cytotoxic effects in certain cancer cells, without damaging normal cells. The objective of the present study was to determine whether gallic acid is able to inhibit human cervical cancer cell viability, proliferation and invasion and suppress cervical cancer cell-mediated angiogenesis. Treatment of HeLa...

  19. Extracellular ATP inhibits Schwann cell dedifferentiation and proliferation in an ex vivo model of Wallerian degeneration

    International Nuclear Information System (INIS)

    Shin, Youn Ho; Lee, Seo Jin; Jung, Junyang

    2013-01-01

    Highlights: ► ATP-treated sciatic explants shows the decreased expression of p75NGFR. ► Extracellular ATP inhibits the expression of phospho-ERK1/2. ► Lysosomal exocytosis is involved in Schwann cell dedifferentiation. ► Extracellular ATP blocks Schwann cell proliferation in sciatic explants. -- Abstract: After nerve injury, Schwann cells proliferate and revert to a phenotype that supports nerve regeneration. This phenotype-changing process can be viewed as Schwann cell dedifferentiation. Here, we investigated the role of extracellular ATP in Schwann cell dedifferentiation and proliferation during Wallerian degeneration. Using several markers of Schwann cell dedifferentiation and proliferation in sciatic explants, we found that extracellular ATP inhibits Schwann cell dedifferentiation and proliferation during Wallerian degeneration. Furthermore, the blockage of lysosomal exocytosis in ATP-treated sciatic explants is sufficient to induce Schwann cell dedifferentiation. Together, these findings suggest that ATP-induced lysosomal exocytosis may be involved in Schwann cell dedifferentiation.

  20. Sevoflurane suppresses proliferation by upregulating microRNA-203 in breast cancer cells.

    Science.gov (United States)

    Liu, Jiaying; Yang, Longqiu; Guo, Xia; Jin, Guangli; Wang, Qimin; Lv, Dongdong; Liu, Junli; Chen, Qiu; Song, Qiong; Li, Baolin

    2018-05-03

    Rapid proliferation is one of the critical characteristics of breast cancer. However, the underlying regulatory mechanism of breast cancer cell proliferation is largely unclear. The present study indicated that sevoflurane, one of inhalational anesthetics, could significantly suppress breast cancer cell proliferation by arresting cell cycle at G1 phase. Notably, the rescue experiment indicated that miR-203 was upregulated by sevoflurane and mediated the function of sevoflurane on suppressing the breast cancer cell proliferation. The present study indicated the function of the sevoflurane/miR-203 signaling pathway on regulating breast cancer cell proliferation. These results provide mechanistic insight into how the sevoflurane/miR-203 signaling pathway supresses proliferation of breast cancer cells, suggesting the sevoflurane/miR-203 pathway may be a potential target in the treatment of breast cancer.

  1. Folic Acid supplementation stimulates notch signaling and cell proliferation in embryonic neural stem cells.

    Science.gov (United States)

    Liu, Huan; Huang, Guo-Wei; Zhang, Xu-Mei; Ren, Da-Lin; X Wilson, John

    2010-09-01

    The present study investigated the effect of folic acid supplementation on the Notch signaling pathway and cell proliferation in rat embryonic neural stem cells (NSCs). The NSCs were isolated from E14-16 rat brain and grown as neurospheres in serum-free suspension culture. Individual cultures were assigned to one of 3 treatment groups that differed according to the concentration of folic acid in the medium: Control (baseline folic acid concentration of 4 mg/l), low folic acid supplementation (4 mg/l above baseline, Folate-L) and high folic acid supplementation (40 mg/l above baseline, Folate-H). NSCs were identified by their expression of immunoreactive nestin and proliferating cells by incorporation of 5'bromo-2'deoxyuridine. Cell proliferation was also assessed by methyl thiazolyl tetrazolium assay. Notch signaling was analyzed by real-time PCR and western blot analyses of the expression of Notch1 and hairy and enhancer of split 5 (Hes5). Supplementation of NSCs with folic acid increased the mRNA and protein expression levels of Notch1 and Hes5. Folic acid supplementation also stimulated NSC proliferation dose-dependently. Embryonic NSCs respond to folic acid supplementation with increased Notch signaling and cell proliferation. This mechanism may mediate the effects of folic acid supplementation on neurogenesis in the embryonic nervous system.

  2. Effects of irradiation and cisplatin on human glioma spheroids: inhibition of cell proliferation and cell migration

    NARCIS (Netherlands)

    Fehlauer, Fabian; Muench, Martina; Rades, Dirk; Stalpers, Lukas J. A.; Leenstra, Sieger; van der Valk, Paul; Slotman, Ben; Smid, Ernst J.; Sminia, Peter

    2005-01-01

    Investigation of cell migration and proliferation of human glioma cell line spheroids (CLS) and evaluation of morphology, apoptosis, and immunohistochemical expression of MIB-1, p53, and p21 of organotypic muticellular spheroids (OMS) following cisplatin (CDDP) and irradiation (RT). Spheroids of the

  3. Y-27632 Increases Sensitivity of PANC-1 Cells to EGCG in Regulating Cell Proliferation and Migration.

    Science.gov (United States)

    Liu, Xing; Bi, Yongyi

    2016-10-03

    BACKGROUND The study aimed to investigate the inhibitory effect of (1R,4r)-4-((R)-1-aminoethyl)-N-(pyridin-4-yl) cyclohexanecarboxamide (Y-27632) and (-)-epigallocatechin-3-gallate (EGCG) on the proliferation and migration of PANC-1 cells. EGCG, found in green tea, has been previously shown to be one of the most abundant and powerful catechins in cancer prevention and treatment. Y-27632, a selective inhibitor of rho-associated protein kinase 1, is widely used in treating cardiovascular disease, inflammation, and cancer. MATERIAL AND METHODS PANC-1 cells, maintained in Dulbecco's Modified Eagle's Medium, were treated with dimethyl sulfoxide (control) as well as different concentrations (20, 40, 60, and 80 μg/mL) of EGCG for 48 h. In addition, PANC-1 cells were treated separately with 60 μg/mL EGCG, 20 μM Y-27632, and EGCG combined with Y-27632 (60 μg/mL EGCG + 20 μM Y-27632) for 48 h. The effect of EGCG and Y-27632 on the proliferation and migration of PANC-1 cells was evaluated using Cell Counting Kit-8 and transwell migration assays. The expression of peroxisome proliferator-activated receptor alpha (PPARα) and Caspase-3 mRNA was determined by Quantitative real-time polymerase chain reaction (RT-qPCR). RESULTS EGCG (20-80 μg/mL) inhibited cell viability in a dose-dependent manner. Y-27632 enhanced the sensitivity of PANC-1 cells to EGCG (by increasing the expression of PPARa and Caspase-3 mRNA) and suppressed cell proliferation. PANC-1 cell migration was inhibited by treatment with a combination of EGCG and Y-27632. CONCLUSIONS Y-27632 increases the sensitivity of PANC-1 cells to EGCG in regulating cell proliferation and migration, which is likely to be related to the expression of PPARa mRNA and Caspase-3 mRNA.

  4. Exercise reduces inflammation and cell proliferation in rat colon carcinogenesis.

    Science.gov (United States)

    Demarzo, Marcelo Marcos Piva; Martins, Lisandra Vanessa; Fernandes, Cleverson Rodrigues; Herrero, Fábio Augusto; Perez, Sérgio Eduardo de Andrade; Turatti, Aline; Garcia, Sérgio Britto

    2008-04-01

    There is evidence that the risk of colon cancer is reduced by appropriate levels of physical exercise. Nevertheless, the mechanisms involved in this protective effect of exercise remain largely unknown. Inflammation is emerging as a unifying link between a range of environment exposures and neoplastic risk. The carcinogen dimethyl-hydrazine (DMH) induces an increase in epithelial cell proliferation and in the expression of the inflammation-related enzyme cyclooxigenase-2 (COX-2) in the colon of rats. Our aim was to verify whether these events could be attenuated by exercise. Four groups of eight Wistar rats were used in the experiment. The groups G1 and G3 were sedentary (controls), and the groups G2 and G4 were submitted to 8 wk of swimming training, 5 d.wk. The groups G3 and G4 were given subcutaneous injections of DMH immediately after the exercise protocols. Fifteen days after the neoplasic induction, the rats were sacrificed and the colon was processed for histological examination and immunohistochemistry staining of proliferating cell nuclear antigen (PCNA) and COX-2. We found a significant increase in the PCNA-labeling index in both DMH-treated groups of rats. However, this increase was significantly attenuated in the training group G4 (P < 0.01). Similar results were observed in relation to the COX-2 expression. From our findings, we conclude that exercise training exerts remarkable antiproliferative and antiinflammatory effects in the rat colonic mucosa, suggesting that this may be an important mechanism to explain how exercise protects against colonic cancer.

  5. Non-circadian rhythm in proliferation of haematopoietic stem cells

    International Nuclear Information System (INIS)

    Necas, E.; Znojil, V.

    1988-01-01

    The proportion of haematopoietic stem cells (CFU-s) engaged in DNA synthesis was determined by means of the [ 3 H]-thymidine ([ 3 H]TdR) suicide technique during recovery of bone marrow from the damage caused by a sublethal total body irradiation. In contrast with previous reports the [ 3 H]TdR suicide rate was not permanently increased. It was observed that CFU-s passed through S phase in synchronous waves, following a dose of irradiation of 1.5 Gy. After a dose of 2.6 Gy, there was only one initial wave of increased CFU-s sensitivity to the action of [ 3 H]TdR. Following the depression occurring 26 hr after the irradiation with 2.6 Gy, the proportion of CFU-s killed by the [ 3 H]TdR was permanently increased until 5-6 days after irradiation. Thereafter large differences in the [ 3 H]TdR suicide data were observed among individual mice. Evidence was obtained that individual mice, which had been irradiated by a dose of 2.6 Gy 8-9 days before, had identical values of the CFU-s [ 3 H]TdR suicide rate in the bone marrow from different bones of the lower extremities. The recurrence of the synchronous waves in CFU-s passage through the cell cycle was recorded when the CFU-s population regenerated to only about 10% of its normal value. It is concluded that the synchronous waves in which CFU-s proliferation occurred reflected the action of the control mechanism on CFU-s proliferation. (author)

  6. Non-circadian rhythm in proliferation of haematopoietic stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Necas, E; Znojil, V [Charles Univ., Prague (Czechoslovakia). Faculty of Medicine

    1988-03-01

    The proportion of haematopoietic stem cells (CFU-s) engaged in DNA synthesis was determined by means of the (/sup 3/H)-thymidine ((/sup 3/H)TdR) suicide technique during recovery of bone marrow from the damage caused by a sublethal total body irradiation. In contrast with previous reports the (/sup 3/H)TdR suicide rate was not permanently increased. It was observed that CFU-s passed through S phase in synchronous waves, following a dose of irradiation of 1.5 Gy. After a dose of 2.6 Gy, there was only one initial wave of increased CFU-s sensitivity to the action of (/sup 3/H)TdR. Following the depression occurring 26 hr after the irradiation with 2.6 Gy, the proportion of CFU-s killed by the (/sup 3/H)TdR was permanently increased until 5-6 days after irradiation. Thereafter large differences in the (/sup 3/H)TdR suicide data were observed among individual mice. Evidence was obtained that individual mice, which had been irradiated by a dose of 2.6 Gy 8-9 days before, had identical values of the CFU-s (/sup 3/H)TdR suicide rate in the bone marrow from different bones of the lower extremities. The recurrence of the synchronous waves in CFU-s passage through the cell cycle was recorded when the CFU-s population regenerated to only about 10% of its normal value. It is concluded that the synchronous waves in which CFU-s proliferation occurred reflected the action of the control mechanism on CFU-s proliferation. (author).

  7. Phenotype Analysis and Quantification of Proliferating Cells in the Cortical Gray Matter of the Adult Rat

    International Nuclear Information System (INIS)

    Mori, Tetsuji; Wakabayashi, Taketoshi; Takamori, Yasuharu; Kitaya, Kotaro; Yamada, Hisao

    2009-01-01

    In intact adult mammalian brains, there are two neurogenic regions: the subependymal zone and the subgranular layer of the hippocampus. Even outside these regions, small numbers of proliferating precursors do exist. Many studies suggest that the majority of these are oligodendrocyte precursors that express NG2, a chondroitin sulfate proteoglycan, and most of the residual proliferating cells seem to be endothelial cells. However, it is still unclear whether NG2-immunonegative proliferating precursors are present, because previous studies have neglected their possible existence. In this study, we systematically analyzed the phenotypes of the proliferating cells in the intact adult rat cortical gray matter. We improved our techniques and carefully characterized the proliferating cells, because there were several problems with identifying and quantifying the proliferating cells: the detection of NG2-expressing cells was dependent on the fixation condition; there were residual proliferating leukocytes in the blood vessels; and two anti-NG2 antibodies gave rise to different staining patterns. Moreover, we used two methods, BrdU and Ki67 immunostaining, to quantify the proliferating cells. Our results strongly suggest that in the intact adult cerebral cortical gray matter, there were only two types of proliferating cells: the majority were NG2-expressing cells, including pericytes, and the rest were endothelial cells

  8. Impact of Mesenchymal Stem Cell secreted PAI-1 on colon cancer cell migration and proliferation

    International Nuclear Information System (INIS)

    Hogan, Niamh M.; Joyce, Myles R.; Murphy, J. Mary; Barry, Frank P.; O’Brien, Timothy; Kerin, Michael J.; Dwyer, Roisin M.

    2013-01-01

    Highlights: •MSCs were directly co-cultured with colorectal cancer (CRC) cells on 3D scaffolds. •MSCs influence CRC protein/gene expression, proliferation and migration. •We report a significant functional role of MSC-secreted PAI-1 in colon cancer. -- Abstract: Mesenchymal Stem Cells are known to engraft and integrate into the architecture of colorectal tumours, with little known regarding their fate following engraftment. This study aimed to investigate mediators of Mesenchymal Stem Cell (MSC) and colon cancer cell (CCC) interactions. Mesenchymal Stem Cells and colon cancer cells (HT29 and HCT-116) were cultured individually or in co-culture on 3-dimensional scaffolds. Conditioned media containing all secreted factors was harvested at day 1, 3 and 7. Chemokine secretion and expression were analyzed by Chemi-array, ELISA (Macrophage migration inhibitory factor (MIF), plasminogen activator inhibitor type 1 (PAI-1)) and RQ-PCR. Colon cancer cell migration and proliferation in response to recombinant PAI-1, MSCs and MSCs + antibody to PAI-1 was analyzed using Transwell inserts and an MTS proliferation assay respectively. Chemi-array revealed secretion of a wide range of factors by each cell population, including PAI-1and MIF. ELISA analysis revealed Mesenchymal Stem Cells to secrete the highest levels of PAI-1 (MSC mean 10.6 ng/mL, CCC mean 1.01 ng/mL), while colon cancer cells were the principal source of MIF. MSC-secreted PAI-1 stimulated significant migration of both CCC lines, with an antibody to the chemokine shown to block this effect (67–88% blocking,). A cell-line dependant effect on CCC proliferation was shown for Mesenchymal Stem Cell-secreted PAI-1 with HCT-116 cells showing decreased proliferation at all concentrations, and HT29 cells showing increased proliferation in the presence of higher PAI-1 levels. This is the first study to identify PAI-1 as an important mediator of Mesenchymal Stem Cell/colon cancer cell interactions and highlights the

  9. Impact of Mesenchymal Stem Cell secreted PAI-1 on colon cancer cell migration and proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Hogan, Niamh M. [Discipline of Surgery, School of Medicine, National University of Ireland, Galway (Ireland); Joyce, Myles R. [Department of Colorectal Surgery, University College Hospital, Galway (Ireland); Murphy, J. Mary; Barry, Frank P.; O’Brien, Timothy [Regenerative Medicine Institute, National University of Ireland, Galway (Ireland); Kerin, Michael J. [Discipline of Surgery, School of Medicine, National University of Ireland, Galway (Ireland); Dwyer, Roisin M., E-mail: roisin.dwyer@nuigalway.ie [Discipline of Surgery, School of Medicine, National University of Ireland, Galway (Ireland)

    2013-06-14

    Highlights: •MSCs were directly co-cultured with colorectal cancer (CRC) cells on 3D scaffolds. •MSCs influence CRC protein/gene expression, proliferation and migration. •We report a significant functional role of MSC-secreted PAI-1 in colon cancer. -- Abstract: Mesenchymal Stem Cells are known to engraft and integrate into the architecture of colorectal tumours, with little known regarding their fate following engraftment. This study aimed to investigate mediators of Mesenchymal Stem Cell (MSC) and colon cancer cell (CCC) interactions. Mesenchymal Stem Cells and colon cancer cells (HT29 and HCT-116) were cultured individually or in co-culture on 3-dimensional scaffolds. Conditioned media containing all secreted factors was harvested at day 1, 3 and 7. Chemokine secretion and expression were analyzed by Chemi-array, ELISA (Macrophage migration inhibitory factor (MIF), plasminogen activator inhibitor type 1 (PAI-1)) and RQ-PCR. Colon cancer cell migration and proliferation in response to recombinant PAI-1, MSCs and MSCs + antibody to PAI-1 was analyzed using Transwell inserts and an MTS proliferation assay respectively. Chemi-array revealed secretion of a wide range of factors by each cell population, including PAI-1and MIF. ELISA analysis revealed Mesenchymal Stem Cells to secrete the highest levels of PAI-1 (MSC mean 10.6 ng/mL, CCC mean 1.01 ng/mL), while colon cancer cells were the principal source of MIF. MSC-secreted PAI-1 stimulated significant migration of both CCC lines, with an antibody to the chemokine shown to block this effect (67–88% blocking,). A cell-line dependant effect on CCC proliferation was shown for Mesenchymal Stem Cell-secreted PAI-1 with HCT-116 cells showing decreased proliferation at all concentrations, and HT29 cells showing increased proliferation in the presence of higher PAI-1 levels. This is the first study to identify PAI-1 as an important mediator of Mesenchymal Stem Cell/colon cancer cell interactions and highlights the

  10. Proliferation of cultured mouse choroid plexus epithelial cells.

    Directory of Open Access Journals (Sweden)

    Basam Z Barkho

    Full Text Available The choroid plexus (ChP epithelium is a multifunctional tissue found in the ventricles of the brain. The major function of the ChP epithelium is to produce cerebrospinal fluid (CSF that bathes and nourishes the central nervous system (CNS. In addition to the CSF, ChP epithelial cells (CPECs produce and secrete numerous neurotrophic factors that support brain homeostasis, such as adult hippocampal neurogenesis. Accordingly, damage and dysfunction to CPECs are thought to accelerate and intensify multiple disease phenotypes, and CPEC regeneration would represent a potential therapeutic approach for these diseases. However, previous reports suggest that CPECs rarely divide, although this has not been extensively studied in response to extrinsic factors. Utilizing a cell-cycle reporter mouse line and live cell imaging, we identified scratch injury and the growth factors insulin-like growth factor 1 (IGF-1 and epidermal growth factor (EGF as extrinsic cues that promote increased CPEC expansion in vitro. Furthermore, we found that IGF-1 and EGF treatment enhances scratch injury-induced proliferation. Finally, we established whole tissue explant cultures and observed that IGF-1 and EGF promote CPEC division within the intact ChP epithelium. We conclude that although CPECs normally have a slow turnover rate, they expand in response to external stimuli such as injury and/or growth factors, which provides a potential avenue for enhancing ChP function after brain injury or neurodegeneration.

  11. Modulatory effects of quercetin on proliferation and differentiation of the human colorectal cell line Caco-2

    NARCIS (Netherlands)

    Dihal, A.A.; Woutersen, R.A.; Ommen, B.v.; Rietjens, I.M.C.M.; Stierum, R.H.

    2006-01-01

    The effect of the dietary flavonoid quercetin was investigated on proliferation and differentiation of the human colon cancer cell line Caco-2. Confluent Caco-2 monolayers exposed to quercetin showed a biphasic effect on cell proliferation and a decrease in cell differentiation (0.001

  12. Bone marrow mesenchymal stem cells stimulate proliferation and neuronal differentiation of retinal progenitor cells.

    Directory of Open Access Journals (Sweden)

    Jing Xia

    Full Text Available During retina development, retinal progenitor cell (RPC proliferation and differentiation are regulated by complex inter- and intracellular interactions. Bone marrow mesenchymal stem cells (BMSCs are reported to express a variety of cytokines and neurotrophic factors, which have powerful trophic and protective functions for neural tissue-derived cells. Here, we show that the expanded RPC cultures treated with BMSC-derived conditioned medium (CM which was substantially enriched for bFGF and CNTF, expressed clearly increased levels of nuclear receptor TLX, an essential regulator of neural stem cell (NSC self-renewal, as well as betacellulin (BTC, an EGF-like protein described as supporting NSC expansion. The BMSC CM- or bFGF-treated RPCs also displayed an obviously enhanced proliferation capability, while BMSC CM-derived bFGF knocked down by anti-bFGF, the effect of BMSC CM on enhancing RPC proliferation was partly reversed. Under differentiation conditions, treatment with BMSC CM or CNTF markedly favoured RPC differentiation towards retinal neurons, including Brn3a-positive retinal ganglion cells (RGCs and rhodopsin-positive photoreceptors, and clearly diminished retinal glial cell differentiation. These findings demonstrate that BMSCs supported RPC proliferation and neuronal differentiation which may be partly mediated by BMSC CM-derived bFGF and CNTF, reveal potential limitations of RPC culture systems, and suggest a means for optimizing RPC cell fate determination in vitro.

  13. Trehalose improves cell proliferation and dehydration tolerance of human HaCaT cells

    Directory of Open Access Journals (Sweden)

    Lee Kyung Eun

    2015-01-01

    Full Text Available Trehalose is a disaccharide molecule that serves as a natural osmotic regulator in halophilic microorganisms and plants but not in mammals. We observed that human HaCaT cells supplied with trehalose improved cell proliferation and extended viability under dehydration. In HaCaT cells, in response to increasing concentrations of exogenous trehalose, the levels of heat shock protein (HSP 70 increased and matrix metalloproteinase (MMP 1 decreased. Proteome analysis of trehalose-treated HaCaT cells revealed remarkable increases in the levels of proteins involved in cell signaling and the cell cycle, including p21 activated kinase I, Sec I family domain protein and elongation factor G. Moreover, the proteins for cell stress resistance, tryptophan hydroxylase, serine/cysteine proteinase inhibitors and vitamin D receptors were also increased. In addition, the proteins responsible for the maintenance of the cytoskeleton and cellular structures including procollagen-lysine dioxygenase, vinculin and ezrin were increased. Proteomic data revealed that trehalose affected HaCaT cells by inducing the proteins involved in cell proliferation. These results suggest that trehalose improves the proliferation and dehydration tolerance of HaCaT cells by inducing proteins involved in cell growth and dehydration protection.

  14. ERK5 and cell proliferation: nuclear localization is what matters

    Directory of Open Access Journals (Sweden)

    Nestor Gomez

    2016-09-01

    Full Text Available ERK5, the last MAP kinase family member discovered, is activated by the upstream kinase MEK5 in response to growth factors and stress stimulation. MEK5-ERK5 pathway has been associated to different cellular processes, playing a crucial role in cell proliferation in normal and cancer cells by mechanisms that are both dependent and independent of its kinase activity. Thus, nuclear ERK5 activates transcription factors by either direct phosphorylation or acting as co-activator thanks to a unique transcriptional activation TAD domain located at its C-terminal tail. Consequently, ERK5 has been proposed as an interesting target to tackle different cancers, and either inhibitors of ERK5 activity or silencing the protein have shown antiproliferative activity in cancer cells and to block tumour growth in animal models. Here, we review the different mechanisms involved in ERK5 nuclear translocation and their consequences. Inactive ERK5 resides in the cytosol, forming a complex with Hsp90-Cdc37 superchaperone. In a canonical mechanism, MEK5-dependent activation results in ERK5 C-terminal autophosphorylation, Hsp90 dissociation and nuclear translocation. This mechanism integrates signals such as growth factors and stresses that activate the MEK5-ERK5 pathway. Importantly, two other mechanisms, MEK5-independent, have been recently described. These mechanisms allow nuclear shuttling of kinase-inactive forms of ERK5. Although lacking kinase activity, these forms activate transcription by interacting with transcription factors through the TAD domain. Both mechanisms also require Hsp90 dissociation previous to nuclear translocation. One mechanism involves phosphorylation of the C-terminal tail of ERK5 by kinases that are activated during mitosis, such as Cyclin-dependent kinase-1. The second mechanism involves overexpression of chaperone Cdc37, an oncogene that is overexpressed in cancers such as prostate adenocarcinoma, where it collaborates with ERK5 to promote

  15. The effect of cerium valence states at cerium oxide nanoparticle surfaces on cell proliferation

    KAUST Repository

    Naganuma, Tamaki

    2014-05-01

    Understanding and controlling cell proliferation on biomaterial surfaces is critical for scaffold/artificial-niche design in tissue engineering. The mechanism by which underlying integrin ligates with functionalized biomaterials to induce cell proliferation is still not completely understood. In this study, poly-l-lactide (PL) scaffold surfaces were functionalized using layers of cerium oxide nanoparticles (CNPs), which have recently attracted attention for use in therapeutic application due to their catalytic ability of Ce4+ and Ce3+ sites. To isolate the influence of Ce valance states of CNPs on cell proliferation, human mesenchymal stem cells (hMSCs) and osteoblast-like cells (MG63) were cultured on the PL/CNP surfaces with dominant Ce4+ and Ce3+ regions. Despite cell type (hMSCs and MG63 cells), different surface features of Ce4+ and Ce3+ regions clearly promoted and inhibited cell spreading, migration and adhesion behavior, resulting in rapid and slow cell proliferation, respectively. Cell proliferation results of various modified CNPs with different surface charge and hydrophobicity/hydrophilicity, indicate that Ce valence states closely correlated with the specific cell morphologies and cell-material interactions that trigger cell proliferation. This finding suggests that the cell-material interactions, which influence cell proliferation, may be controlled by introduction of metal elements with different valence states onto the biomaterial surface. © 2014 Elsevier Ltd.

  16. Effect of irradiation on human T-cell proliferation: low dose irradiation stimulates mitogen-induced proliferation and function of the suppressor/cytotoxic T-cell subset

    International Nuclear Information System (INIS)

    Gualde, N.; Goodwin, J.S.

    1984-01-01

    Unfractionated human T cells exposed to 10-50 rad of X irradiation incorporated less [ 3 H]thymidine than nonirradiated T cells when subsequently cultured with PHA or Con A. The cytotoxic/suppressor T-cell subset, isolated as either OKT8(+) or OKT4(-) cells, demonstrated significantly enhanced [ 3 H]thymidine incorporation in PHA- or Con A-stimulated cultures after exposure to 10-50 rad, compared to unirradiated cells, while the proliferation of the OKT4(+) helper/inducer subset was inhibited by low dose irradiation. It has been previously reported that approximately 30% of the cytotoxic/suppressor subset also stains with OKM1. When the cytotoxic/suppressor subset was further subdivided into OKT4(-), OKM1(+), and OKT4(-), OKM1(-) cells, proliferation of the OKT4(-), OKM1(+) population was inhibited by exposure to 25 rad while proliferation of the OKT4(-), OKM1(-) population was stimulated. The increase in proliferation of the cytotoxic/suppressor T-cell subset after low dose irradiation is paralleled by an increase in suppressor activity of these cells. T cells exposed to 25 rad and then cultured with Con A for 48 hr caused greater inhibition of IgG production when added to fresh autologous lymphocytes stimulated by pokeweed mitogen than did unirradiated cells. Thus, low dose irradiation enhances both the proliferation and function of the human suppressor T-cell subset

  17. Acetylcholine release by human colon cancer cells mediates autocrine stimulation of cell proliferation.

    Science.gov (United States)

    Cheng, Kunrong; Samimi, Roxana; Xie, Guofeng; Shant, Jasleen; Drachenberg, Cinthia; Wade, Mark; Davis, Richard J; Nomikos, George; Raufman, Jean-Pierre

    2008-09-01

    Most colon cancers overexpress M3 muscarinic receptors (M3R), and post-M3R signaling stimulates human colon cancer cell proliferation. Acetylcholine (ACh), a muscarinic receptor ligand traditionally regarded as a neurotransmitter, may be produced by nonneuronal cells. We hypothesized that ACh release by human colon cancer cells results in autocrine stimulation of proliferation. H508 human colon cancer cells, which have robust M3R expression, were used to examine effects of muscarinic receptor antagonists, acetylcholinesterase inhibitors, and choline transport inhibitors on cell proliferation. A nonselective muscarinic receptor antagonist (atropine), a selective M3R antagonist (p-fluorohexahydro-sila-difenidol hydrochloride), and a choline transport inhibitor (hemicholinum-3) all inhibited unstimulated H508 colon cancer cell proliferation by approximately 40% (P<0.005). In contrast, two acetylcholinesterase inhibitors (eserine-hemisulfate and bis-9-amino-1,2,3,4-tetrahydroacridine) increased proliferation by 2.5- and 2-fold, respectively (P<0.005). By using quantitative real-time PCR, expression of choline acetyltransferase (ChAT), a critical enzyme for ACh synthesis, was identified in H508, WiDr, and Caco-2 colon cancer cells. By using high-performance liquid chromatography-electrochemical detection, released ACh was detected in H508 and Caco-2 cell culture media. Immunohistochemistry in surgical specimens revealed weak or no cytoplasmic staining for ChAT in normal colon enterocytes (n=25) whereas half of colon cancer specimens (n=24) exhibited moderate to strong staining (P<0.005). We conclude that ACh is an autocrine growth factor in colon cancer. Mechanisms that regulate colon epithelial cell production and release of ACh warrant further investigation.

  18. Transient inhibition of cell proliferation does not compromise self-renewal of mouse embryonic stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ruoxing [Department of Biological Sciences, The University of Southern Mississippi, 118 College Drive 5018, Hattiesburg, MS 39406 (United States); Guo, Yan-Lin, E-mail: yanlin.guo@usm.edu [Department of Biological Sciences, The University of Southern Mississippi, 118 College Drive 5018, Hattiesburg, MS 39406 (United States)

    2012-10-01

    Embryonic stem cells (ESCs) have unlimited capacity for self-renewal and can differentiate into various cell types when induced. They also have an unusual cell cycle control mechanism driven by constitutively active cyclin dependent kinases (Cdks). In mouse ESCs (mESCs). It is proposed that the rapid cell proliferation could be a necessary part of mechanisms that maintain mESC self-renewal and pluripotency, but this hypothesis is not in line with the finding in human ESCs (hESCs) that the length of the cell cycle is similar to differentiated cells. Therefore, whether rapid cell proliferation is essential for the maintenance of mESC state remains unclear. We provide insight into this uncertainty through chemical intervention of mESC cell cycle. We report here that inhibition of Cdks with olomoucine II can dramatically slow down cell proliferation of mESCs with concurrent down-regulation of cyclin A, B and E, and the activation of the Rb pathway. However, mESCs display can recover upon the removal of olomoucine II and are able to resume normal cell proliferation without losing self-renewal and pluripotency, as demonstrated by the expression of ESC markers, colony formation, embryoid body formation, and induced differentiation. We provide a mechanistic explanation for these observations by demonstrating that Oct4 and Nanog, two major transcription factors that play critical roles in the maintenance of ESC properties, are up-regulated via de novo protein synthesis when the cells are exposed to olomoucine II. Together, our data suggest that short-term inhibition of cell proliferation does not compromise the basic properties of mESCs. -- Highlights: Black-Right-Pointing-Pointer Inhibition of Cdks slows down mESCs proliferation. Black-Right-Pointing-Pointer mESCs display remarkable recovery capacity from short-term cell cycle interruption. Black-Right-Pointing-Pointer Short-term cell cycle interruption does not compromise mESC self-renewal. Black

  19. Transient inhibition of cell proliferation does not compromise self-renewal of mouse embryonic stem cells

    International Nuclear Information System (INIS)

    Wang, Ruoxing; Guo, Yan-Lin

    2012-01-01

    Embryonic stem cells (ESCs) have unlimited capacity for self-renewal and can differentiate into various cell types when induced. They also have an unusual cell cycle control mechanism driven by constitutively active cyclin dependent kinases (Cdks). In mouse ESCs (mESCs). It is proposed that the rapid cell proliferation could be a necessary part of mechanisms that maintain mESC self-renewal and pluripotency, but this hypothesis is not in line with the finding in human ESCs (hESCs) that the length of the cell cycle is similar to differentiated cells. Therefore, whether rapid cell proliferation is essential for the maintenance of mESC state remains unclear. We provide insight into this uncertainty through chemical intervention of mESC cell cycle. We report here that inhibition of Cdks with olomoucine II can dramatically slow down cell proliferation of mESCs with concurrent down-regulation of cyclin A, B and E, and the activation of the Rb pathway. However, mESCs display can recover upon the removal of olomoucine II and are able to resume normal cell proliferation without losing self-renewal and pluripotency, as demonstrated by the expression of ESC markers, colony formation, embryoid body formation, and induced differentiation. We provide a mechanistic explanation for these observations by demonstrating that Oct4 and Nanog, two major transcription factors that play critical roles in the maintenance of ESC properties, are up-regulated via de novo protein synthesis when the cells are exposed to olomoucine II. Together, our data suggest that short-term inhibition of cell proliferation does not compromise the basic properties of mESCs. -- Highlights: ► Inhibition of Cdks slows down mESCs proliferation. ► mESCs display remarkable recovery capacity from short-term cell cycle interruption. ► Short-term cell cycle interruption does not compromise mESC self-renewal. ► Oct4 and Nanog are up-regulated via de novo synthesis by cell cycle interruption.

  20. Gallic acid reduces cell viability, proliferation, invasion and angiogenesis in human cervical cancer cells

    Science.gov (United States)

    ZHAO, BING; HU, MENGCAI

    2013-01-01

    Gallic acid is a trihydroxybenzoic acid, also known as 3,4,5-trihydroxybenzoic acid, which is present in plants worldwide, including Chinese medicinal herbs. Gallic acid has been shown to have cytotoxic effects in certain cancer cells, without damaging normal cells. The objective of the present study was to determine whether gallic acid is able to inhibit human cervical cancer cell viability, proliferation and invasion and suppress cervical cancer cell-mediated angiogenesis. Treatment of HeLa and HTB-35 human cancer cells with gallic acid decreased cell viability in a dose-dependent manner. BrdU proliferation and tube formation assays indicated that gallic acid significantly decreased human cervical cancer cell proliferation and tube formation in human umbilical vein endothelial cells, respectively. Additionally, gallic acid decreased HeLa and HTB-35 cell invasion in vitro. Western blot analysis demonstrated that the expression of ADAM17, EGFR, p-Akt and p-Erk was suppressed by gallic acid in the HeLa and HTB-35 cell lines. These data indicate that the suppression of ADAM17 and the downregulation of the EGFR, Akt/p-Akt and Erk/p-Erk signaling pathways may contribute to the suppression of cancer progression by Gallic acid. Gallic acid may be a valuable candidate for the treatment of cervical cancer. PMID:24843386

  1. Amplification of neural stem cell proliferation by intermediate progenitor cells in Drosophila brain development

    Directory of Open Access Journals (Sweden)

    Bello Bruno C

    2008-02-01

    Full Text Available Abstract Background In the mammalian brain, neural stem cells divide asymmetrically and often amplify the number of progeny they generate via symmetrically dividing intermediate progenitors. Here we investigate whether specific neural stem cell-like neuroblasts in the brain of Drosophila might also amplify neuronal proliferation by generating symmetrically dividing intermediate progenitors. Results Cell lineage-tracing and genetic marker analysis show that remarkably large neuroblast lineages exist in the dorsomedial larval brain of Drosophila. These lineages are generated by brain neuroblasts that divide asymmetrically to self renew but, unlike other brain neuroblasts, do not segregate the differentiating cell fate determinant Prospero to their smaller daughter cells. These daughter cells continue to express neuroblast-specific molecular markers and divide repeatedly to produce neural progeny, demonstrating that they are proliferating intermediate progenitors. The proliferative divisions of these intermediate progenitors have novel cellular and molecular features; they are morphologically symmetrical, but molecularly asymmetrical in that key differentiating cell fate determinants are segregated into only one of the two daughter cells. Conclusion Our findings provide cellular and molecular evidence for a new mode of neurogenesis in the larval brain of Drosophila that involves the amplification of neuroblast proliferation through intermediate progenitors. This type of neurogenesis bears remarkable similarities to neurogenesis in the mammalian brain, where neural stem cells as primary progenitors amplify the number of progeny they generate through generation of secondary progenitors. This suggests that key aspects of neural stem cell biology might be conserved in brain development of insects and mammals.

  2. Kaempferol inhibits cell proliferation and glycolysis in esophagus squamous cell carcinoma via targeting EGFR signaling pathway.

    Science.gov (United States)

    Yao, Shihua; Wang, Xiaowei; Li, Chunguang; Zhao, Tiejun; Jin, Hai; Fang, Wentao

    2016-08-01

    Antitumor activity of kaempferol has been studied in various tumor types, but its potency in esophagus squamous cell carcinoma is rarely known. Here, we reported the activity of kaempferol against esophagus squamous cell carcinoma as well as its antitumor mechanisms. Results of cell proliferation and colony formation assay showed that kaempferol substantially inhibited tumor cell proliferation and clone formation in vitro. Flow cytometric analysis demonstrated that tumor cells were induced G0/G1 phase arrest after kaempferol treatment, and the expression of protein involved in cell cycle regulation was dramatically changed. Except the potency on cell proliferation, we also discovered that kaempferol had a significant inhibitory effect against tumor glycolysis. With the downregulation of hexokinase-2, glucose uptake and lactate production in tumor cells were dramatically declined. Mechanism studies revealed kaempferol had a direct effect on epidermal growth factor receptor (EGFR) activity, and along with the inhibition of EGFR, its downstream signaling pathways were also markedly suppressed. Further investigations found that exogenous overexpression of EGFR in tumor cells substantially attenuated glycolysis suppression induced by kaempferol, which implied that EGFR also played an important role in kaempferol-mediated glycolysis inhibition. Finally, the antitumor activity of kaempferol was validated in xenograft model and kaempferol prominently restrained tumor growth in vivo. Meanwhile, dramatic decrease of EGFR activity and hexokinase-2 expression were observed in kaempferol-treated tumor tissue, which confirmed these findings in vitro. Briefly, these studies suggested that kaempferol, or its analogues, may serve as effective candidates for esophagus squamous cell carcinoma management.

  3. Matrix stiffness reverses the effect of actomyosin tension on cell proliferation.

    Science.gov (United States)

    Mih, Justin D; Marinkovic, Aleksandar; Liu, Fei; Sharif, Asma S; Tschumperlin, Daniel J

    2012-12-15

    The stiffness of the extracellular matrix exerts powerful effects on cell proliferation and differentiation, but the mechanisms transducing matrix stiffness into cellular fate decisions remain poorly understood. Two widely reported responses to matrix stiffening are increases in actomyosin contractility and cell proliferation. To delineate their relationship, we modulated cytoskeletal tension in cells grown across a physiological range of matrix stiffnesses. On both synthetic and naturally derived soft matrices, and across a panel of cell types, we observed a striking reversal of the effect of inhibiting actomyosin contractility, switching from the attenuation of proliferation on rigid substrates to the robust promotion of proliferation on soft matrices. Inhibiting contractility on soft matrices decoupled proliferation from cytoskeletal tension and focal adhesion organization, but not from cell spread area. Our results demonstrate that matrix stiffness and actomyosin contractility converge on cell spreading in an unexpected fashion to control a key aspect of cell fate.

  4. 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...

  5. H2A/K pseudogene mutation may promote cell proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Jisheng; Jing, Ruirui; Lv, Xin; Wang, Xiaoyue; Li, Junqiang; Li, Lin; Li, Cuiling; Wang, Daoguang; Bi, Baibing; Chen, Xinjun [Cancer Research Center, Shandong University School of Medicine, Jinan 250012 (China); Yang, Jing-Hua, E-mail: sdu_crc_group1@126.com [Cancer Research Center, Shandong University School of Medicine, Jinan 250012 (China); Department of Surgery, VA Boston Healthcare System, Boston University School of Medicine, Boston 510660, MA (United States)

    2016-05-15

    Highlights: • The mutant H2A/K pseudogene is active. • The mutant H2A/K pseudogene can promote cell proliferation. - Abstract: Little attention has been paid to the histone H2A/K pseudogene. Results from our laboratory showed that 7 of 10 kidney cancer patients carried a mutant H2A/K pseudogene; therefore, we were interested in determining the relationship between mutant H2A/K and cell proliferation. We used shotgun and label-free proteomics methods to study whether mutant H2A/K lncRNAs affected cell proliferation. Quantitative proteomic analysis indicated that the expression of mutant H2A/K lncRNAs resulted in the upregulation of many oncogenes, which promoted cell proliferation. Further interaction analyses revealed that a proliferating cell nuclear antigen (PCNA)-protein interaction network, with PCNA in the center, contributes to cell proliferation in cells expressing the mutant H2A/K lncRNAs. Western blotting confirmed the critical upregulation of PCNA by mutant H2A/K lncRNA expression. Finally, the promotion of cell proliferation by mutant H2A/K lncRNAs (C290T, C228A and A45G) was confirmed using cell proliferation assays. Although we did not determine the exact mechanism by which the oncogenes were upregulated by the mutant H2A/K lncRNAs, we confirmed that the mutant H2A/K lncRNAs promoted cell proliferation by upregulating PCNA and other oncogenes. The hypothesis that cell proliferation is promoted by the mutant H2A/K lncRNAs was supported by the protein expression and cell proliferation assay results. Therefore, mutant H2A/K lncRNAs may be a new factor in renal carcinogenesis.

  6. Adipose-derived stromal cells inhibit prostate cancer cell proliferation inducing apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Takahara, Kiyoshi [Department of Urology, Faculty of Medicine, Osaka Medical College, Osaka (Japan); Ii, Masaaki, E-mail: masaii@art.osaka-med.ac.jp [Department of Pharmacology, Faculty of Medicine, Osaka Medical College, Osaka (Japan); Inamoto, Teruo; Komura, Kazumasa; Ibuki, Naokazu; Minami, Koichiro; Uehara, Hirofumi; Hirano, Hajime; Nomi, Hayahito; Kiyama, Satoshi [Department of Urology, Faculty of Medicine, Osaka Medical College, Osaka (Japan); Asahi, Michio [Department of Pharmacology, Faculty of Medicine, Osaka Medical College, Osaka (Japan); Azuma, Haruhito [Department of Urology, Faculty of Medicine, Osaka Medical College, Osaka (Japan)

    2014-04-18

    Highlights: • AdSC transplantation exhibits inhibitory effect on tumor progressions of PCa cells. • AdSC-induced PCa cell apoptosis may occur via the TGF-β signaling pathway. • High expression of the TGF-β1 gene in AdSCs. - Abstract: Mesenchymal stem cells (MSCs) have generated a great deal of interest in the field of regenerative medicine. Adipose-derived stromal cells (AdSCs) are known to exhibit extensive proliferation potential and can undergo multilineage differentiation, sharing similar characteristics to bone marrow-derived MSCs. However, as the effect of AdSCs on tumor growth has not been studied sufficiently, we assessed the degree to which AdSCs affect the proliferation of prostate cancer (PCa) cell. Human AdSCs exerted an inhibitory effect on the proliferation of androgen-responsive (LNCaP) and androgen-nonresponsive (PC3) human PCa cells, while normal human dermal fibroblasts (NHDFs) did not, and in fact promoted PCa cell proliferation to a degree. Moreover, AdSCs induced apoptosis of LNCaP cells and PC3 cells, activating the caspase3/7 signaling pathway. cDNA microarray analysis suggested that AdSC-induced apoptosis in both LNCaP and PC3 cells was related to the TGF-β signaling pathway. Consistent with our in vitro observations, local transplantation of AdSCs delayed the growth of tumors derived from both LNCaP- and PC3-xenografts in immunodeficient mice. This is the first preclinical study to have directly demonstrated that AdSC-induced PCa cell apoptosis may occur via the TGF-β signaling pathway, irrespective of androgen-responsiveness. Since autologous AdSCs can be easily isolated from adipose tissue without any ethical concerns, we suggest that therapy with these cells could be a novel approach for patients with PCa.

  7. Adipose-derived stromal cells inhibit prostate cancer cell proliferation inducing apoptosis

    International Nuclear Information System (INIS)

    Takahara, Kiyoshi; Ii, Masaaki; Inamoto, Teruo; Komura, Kazumasa; Ibuki, Naokazu; Minami, Koichiro; Uehara, Hirofumi; Hirano, Hajime; Nomi, Hayahito; Kiyama, Satoshi; Asahi, Michio; Azuma, Haruhito

    2014-01-01

    Highlights: • AdSC transplantation exhibits inhibitory effect on tumor progressions of PCa cells. • AdSC-induced PCa cell apoptosis may occur via the TGF-β signaling pathway. • High expression of the TGF-β1 gene in AdSCs. - Abstract: Mesenchymal stem cells (MSCs) have generated a great deal of interest in the field of regenerative medicine. Adipose-derived stromal cells (AdSCs) are known to exhibit extensive proliferation potential and can undergo multilineage differentiation, sharing similar characteristics to bone marrow-derived MSCs. However, as the effect of AdSCs on tumor growth has not been studied sufficiently, we assessed the degree to which AdSCs affect the proliferation of prostate cancer (PCa) cell. Human AdSCs exerted an inhibitory effect on the proliferation of androgen-responsive (LNCaP) and androgen-nonresponsive (PC3) human PCa cells, while normal human dermal fibroblasts (NHDFs) did not, and in fact promoted PCa cell proliferation to a degree. Moreover, AdSCs induced apoptosis of LNCaP cells and PC3 cells, activating the caspase3/7 signaling pathway. cDNA microarray analysis suggested that AdSC-induced apoptosis in both LNCaP and PC3 cells was related to the TGF-β signaling pathway. Consistent with our in vitro observations, local transplantation of AdSCs delayed the growth of tumors derived from both LNCaP- and PC3-xenografts in immunodeficient mice. This is the first preclinical study to have directly demonstrated that AdSC-induced PCa cell apoptosis may occur via the TGF-β signaling pathway, irrespective of androgen-responsiveness. Since autologous AdSCs can be easily isolated from adipose tissue without any ethical concerns, we suggest that therapy with these cells could be a novel approach for patients with PCa

  8. Neuron-NG2 Cell Synapses: Novel Functions for Regulating NG2 Cell Proliferation and Differentiation

    Directory of Open Access Journals (Sweden)

    Qian-Kun Yang

    2013-01-01

    Full Text Available NG2 cells are a population of CNS cells that are distinct from neurons, mature oligodendrocytes, astrocytes, and microglia. These cells can be identified by their NG2 proteoglycan expression. NG2 cells have a highly branched morphology, with abundant processes radiating from the cell body, and express a complex set of voltage-gated channels, AMPA/kainate, and GABA receptors. Neurons notably form classical and nonclassical synapses with NG2 cells, which have varied characteristics and functions. Neuron-NG2 cell synapses could fine-tune NG2 cell activities, including the NG2 cell cycle, differentiation, migration, and myelination, and may be a novel potential therapeutic target for NG2 cell-related diseases, such as hypoxia-ischemia injury and periventricular leukomalacia. Furthermore, neuron-NG2 cell synapses may be correlated with the plasticity of CNS in adulthood with the synaptic contacts passing onto their progenies during proliferation, and synaptic contacts decrease rapidly upon NG2 cell differentiation. In this review, we highlight the characteristics of classical and nonclassical neuron-NG2 cell synapses, the potential functions, and the fate of synaptic contacts during proliferation and differentiation, with the emphasis on the regulation of the NG2 cell cycle by neuron-NG2 cell synapses and their potential underlying mechanisms.

  9. New castanospermine glycoside analogues inhibit breast cancer cell proliferation and induce apoptosis without affecting normal cells.

    Directory of Open Access Journals (Sweden)

    Ghada Allan

    Full Text Available sp²-Iminosugar-type castanospermine analogues have been shown to exhibit anti-tumor activity. However, their effects on cell proliferation and apoptosis and the molecular mechanism at play are not fully understood. Here, we investigated the effect of two representatives, namely the pseudo-S- and C-octyl glycoside 2-oxa-3-oxocastanospermine derivatives SO-OCS and CO-OCS, on MCF-7 and MDA-MB-231 breast cancer and MCF-10A mammary normal cell lines. We found that SO-OCS and CO-OCS inhibited breast cancer cell viability in a concentration- and time-dependent manner. This effect is specific to breast cancer cells as both molecules had no impact on normal MCF-10A cell proliferation. Both drugs induced a cell cycle arrest. CO-OCS arrested cell cycle at G1 and G2/M in MCF-7 and MDA-MB-231 cells respectively. In MCF-7 cells, the G1 arrest is associated with a reduction of CDK4 (cyclin-dependent kinase 4, cyclin D1 and cyclin E expression, pRb phosphorylation, and an overexpression of p21(Waf1/Cip1. In MDA-MB-231 cells, CO-OCS reduced CDK1 but not cyclin B1 expression. SO-OCS accumulated cells in G2/M in both cell lines and this blockade was accompanied by a decrease of CDK1, but not cyclin B1 expression. Furthermore, both drugs induced apoptosis as demonstrated by the increased percentage of annexin V positive cells and Bax/Bcl-2 ratio. Interestingly, in normal MCF-10A cells the two drugs failed to modify cell proliferation, cell cycle progression, cyclins, or CDKs expression. These results demonstrate that the effect of CO-OCS and SO-OCS is triggered by both cell cycle arrest and apoptosis, suggesting that these castanospermine analogues may constitute potential anti-cancer agents against breast cancer.

  10. Cell proliferation markers in the transplanted canine transmissible venereal tumor

    Directory of Open Access Journals (Sweden)

    F.G.A. Santos

    2011-12-01

    Full Text Available Adult male mongrel dogs were subcutaneously transplanted with the canine transmissible venereal tumor (TVT on the hypogastric region. Twelve specimens of tumors were collected, half during the proliferative phase and the other half during the regressive phase. Fragments of the tumor were fixed in 10% buffered formalin and routinely processed for light microscopy. Sections of 4µm were stained by Schorr or AgNOR or either immunostained for MIB1 (Ki67. Schorr stain, AgNOR and MIB1 showed an increased proliferative activity through mitotic index, nuclear argyrophilic protein stain and cycling tumoral cells in the growing tumors, respectively. All of the three cell proliferation markers were able to distinguish the TVT in both evolution phases. MIB1 monoclonal antibody was the best in the morphologic evaluation of growth and regression of TVT. This resulted in higher values than AgNORs counting and mitotic index. MIB1 immunostaining was the most effective parameter of the proliferative activity of TVT. However, a significant correlation has been detected only between mitosis counting and AgNORs.

  11. NoxO1 Controls Proliferation of Colon Epithelial Cells

    Directory of Open Access Journals (Sweden)

    Franziska Moll

    2018-05-01

    Full Text Available AimReactive oxygen species (ROS produced by enzymes of the NADPH oxidase family serve as second messengers for cellular signaling. Processes such as differentiation and proliferation are regulated by NADPH oxidases. In the intestine, due to the exceedingly fast and constant renewal of the epithelium both processes have to be highly controlled and balanced. Nox1 is the major NADPH oxidase expressed in the gut, and its function is regulated by cytosolic subunits such as NoxO1. We hypothesize that the NoxO1-controlled activity of Nox1 contributes to a proper epithelial homeostasis and renewal in the gut.ResultsNoxO1 is highly expressed in the colon. Knockout of NoxO1 reduces the production of superoxide in colon crypts and is not subsidized by an elevated expression of its homolog p47phox. Knockout of NoxO1 increases the proliferative capacity and prevents apoptosis of colon epithelial cells. In mouse models of dextran sulfate sodium (DSS-induced colitis and azoxymethane/DSS induced colon cancer, NoxO1 has a protective role and may influence the population of natural killer cells.ConclusionNoxO1 affects colon epithelium homeostasis and prevents inflammation.

  12. [Effects of three Wenyang Jianpi Tang on cell proliferation and apoptosis of nonalcoholic fatty liver cells].

    Science.gov (United States)

    Yang, Jia-Yao; Tao, Dong-Qing; Liu, Song; Zhang, Shu; Ma, Wei; Shi, Zhao-Hong

    2017-04-01

    To investigate the effects of Sijunzi Tang, Lizhong Tang and Fuzi Lizhong Tang on the cell proliferation and apoptosis of nonalcoholic fatty liver cells through the nonalcoholic fatty liver cell model established by inducing L02 cells with oleic acid. Different concentrations of oleic acid were added into L02 cells to induce the nonalcoholic fatty liver cell model. Oil red O staining was used to observe fatty droplets of fatty liver cells. Automatic biochemical analyzer was used to detect the levels of aspartic transaminase(AST), alanine aminotransferase(ALT), total cholesterol(TC), and triglyceride(TG) in the cell supernatants. There were five groups, namely normal group, model group, model and Sijunzi Tang group, model and Lizhong Tang group, and model and Fuzi Lizhong Tang group. The cell proliferation and apoptosis of the five groups were detected by MTT colorimetry test and flow cytometer. The expressions of PCNA, cleaved caspase-3, cleaved caspase-8, cleaved caspase-9, Bax and Bcl-2 proteins of the five groups were detected by Western blot. The oil red O staining results showed that the optimum concentration of oleic acid that was used to induce nonalcoholic fatty liver cell models was 80 mg•L-1. The levels of AST, ALT, TC and TG in the nonalcoholic fatty liver cell supernatants were higher than that in normal liver cell supernatants(PTang, Lizhong Tang and Fuzi Lizhong Tang could effectively promote the cell proliferation, and inhibit the cellular apoptosis of nonalcoholic fatty liver cells(PTang showed the best effect. Western blot results showed that Sijunzi Tang, Lizhong Tang and Fuzi Lizhong Tang could down-regulate the expressions of cleaved caspase-3, cleaved caspase-8, cleaved caspase-9 and Bax proteins, and up-regulate the expressions of PCNA and Bcl-2 proteins of nonalcoholic fatty liver cells. And Fuzi Lizhong Tang showed the best effect. In conclusion, all of Sijunzi Tang, Lizhong Tang and Fuzi Lizhong Tang could effectively promote the cell

  13. Human retinal pigment epithelial cells inhibit proliferation and IL2R expression of activated T cells

    DEFF Research Database (Denmark)

    Kaestel, Charlotte G; Jørgensen, Annette; Nielsen, Mette

    2002-01-01

    -Thymidine incorporation assay, respectively. T cells and RPE cells were cultured directly together or in a transwell system for determination of the effect of cell contact. The importance of cell surface molecules was examined by application of a panel of blocking antibodies (CD2, CD18, CD40, CD40L, CD54, CD58......) in addition to use of TCR negative T cell lines. The expression of IL2R-alpha -beta and -gamma chains of activated T cells was analysed by flow cytometry after incubation of T cells alone or with RPE cells. Human RPE cells were found to inhibit the proliferation of activated T cells by a cell contact......-beta and -gamma chain expression within 24 hr after removal from the coculture. It is concluded that the cultured human adult and foetal RPE cells inhibit the proliferation of activated T cells by a process that does not involve apoptosis. It depends on cell contact but the involved surface molecules were...

  14. A naringenin–tamoxifen combination impairs cell proliferation and survival of MCF-7 breast cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Hatkevich, Talia; Ramos, Joseph; Santos-Sanchez, Idalys; Patel, Yashomati M., E-mail: ympatel@uncg.edu

    2014-10-01

    Since over 60% of breast cancers are estrogen receptor positive (ER+), many therapies have targeted the ER. The ER is activated by both estrogen binding and phosphorylation. While anti-estrogen therapies, such as tamoxifen (Tam) have been successful they do not target the growth factor promoting phosphorylation of the ER. Other proliferation pathways such as the phosphatidylinositol-3 kinase, (PI3K) and the mitogen-activated protein kinase (MAPK) pathways are activated in breast cancer cells and are associated with poor prognosis. Thus targeting multiple cellular proliferation and survival pathways at the onset of treatment is critical for the development of more effective therapies. The grapefruit flavanone naringenin (Nar) is an inhibitor of both the PI3K and MAPK pathways. Previous studies examining either Nar or Tam used charcoal-stripped serum which removed estrogen as well as other factors. We wanted to use serum containing medium in order to retain all the potential inducers of cell proliferation so as not to exclude any targets of Nar. Here we show that a Nar–Tam combination is more effective than either Tam alone or Nar alone in MCF-7 breast cancer cells. We demonstrate that a Nar–Tam combination impaired cellular proliferation and viability to a greater extent than either component alone in MCF-7 cells. Furthermore, the use of a Nar–Tam combination requires lower concentrations of both compounds to achieve the same effects on proliferation and viability. Nar may function by inhibiting both PI3K and MAPK pathways as well as localizing ERα to the cytoplasm in MCF-7 cells. Our results demonstrate that a Nar–Tam combination induces apoptosis and impairs proliferation signaling to a greater extent than either compound alone. These studies provide critical information for understanding the molecular mechanisms involved in cell proliferation and apoptosis in breast cancer cells. - Highlights: • Nar–Tam impairs cell viability more effectively than

  15. A naringenin–tamoxifen combination impairs cell proliferation and survival of MCF-7 breast cancer cells

    International Nuclear Information System (INIS)

    Hatkevich, Talia; Ramos, Joseph; Santos-Sanchez, Idalys; Patel, Yashomati M.

    2014-01-01

    Since over 60% of breast cancers are estrogen receptor positive (ER+), many therapies have targeted the ER. The ER is activated by both estrogen binding and phosphorylation. While anti-estrogen therapies, such as tamoxifen (Tam) have been successful they do not target the growth factor promoting phosphorylation of the ER. Other proliferation pathways such as the phosphatidylinositol-3 kinase, (PI3K) and the mitogen-activated protein kinase (MAPK) pathways are activated in breast cancer cells and are associated with poor prognosis. Thus targeting multiple cellular proliferation and survival pathways at the onset of treatment is critical for the development of more effective therapies. The grapefruit flavanone naringenin (Nar) is an inhibitor of both the PI3K and MAPK pathways. Previous studies examining either Nar or Tam used charcoal-stripped serum which removed estrogen as well as other factors. We wanted to use serum containing medium in order to retain all the potential inducers of cell proliferation so as not to exclude any targets of Nar. Here we show that a Nar–Tam combination is more effective than either Tam alone or Nar alone in MCF-7 breast cancer cells. We demonstrate that a Nar–Tam combination impaired cellular proliferation and viability to a greater extent than either component alone in MCF-7 cells. Furthermore, the use of a Nar–Tam combination requires lower concentrations of both compounds to achieve the same effects on proliferation and viability. Nar may function by inhibiting both PI3K and MAPK pathways as well as localizing ERα to the cytoplasm in MCF-7 cells. Our results demonstrate that a Nar–Tam combination induces apoptosis and impairs proliferation signaling to a greater extent than either compound alone. These studies provide critical information for understanding the molecular mechanisms involved in cell proliferation and apoptosis in breast cancer cells. - Highlights: • Nar–Tam impairs cell viability more effectively than

  16. Homeobox A7 stimulates breast cancer cell proliferation by up-regulating estrogen receptor-alpha

    International Nuclear Information System (INIS)

    Zhang, Yu; Cheng, Jung-Chien; Huang, He-Feng; Leung, Peter C.K.

    2013-01-01

    Highlights: •HOXA7 regulates MCF7 cell proliferation. •HOXA7 up-regulates ERα expression. •HOXA7 mediates estrogen-induced MCF7 cell proliferation. -- Abstract: Breast cancer is the most common hormone-dependent malignancy in women. Homeobox (HOX) transcription factors regulate many cellular functions, including cell migration, proliferation and differentiation. The aberrant expression of HOX genes has been reported to be associated with human reproductive cancers. Estradiol (E2) and its nuclear receptors, estrogen receptor (ER)-alpha and ER-beta, are known to play critical roles in the regulation of breast cancer cell growth. However, an understanding of the potential relationship between HOXA7 and ER in breast cancer cells is limited. In this study, our results demonstrate that knockdown of HOXA7 in MCF7 cells significantly decreased cell proliferation and ERα expression. In addition, HOXA7 knockdown attenuated E2-induced cell proliferation as well as progesterone receptor (PR) expression. The stimulatory effects of E2 on cell proliferation and PR expression were abolished by co-treatment with ICI 182780, a selective ERα antagonist. In contrast, overexpression of HOXA7 significantly stimulated cell proliferation and ERα expression. Moreover, E2-induced cell proliferation, as well as PR expression, was enhanced by the overexpression of HOXA7. Neither knockdown nor overexpression of HOXA7 affected the ER-beta levels. Our results demonstrate a novel mechanistic role for HOXA7 in modulating breast cancer cell proliferation via regulation of ERα expression. This finding contributes to our understanding of the role HOXA7 plays in regulating the proliferation of ER-positive cancer cells

  17. Homeobox A7 stimulates breast cancer cell proliferation by up-regulating estrogen receptor-alpha

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yu [Department of Reproductive Endocrinology, Women’s Hospital, School of Medicine, Zhejiang University, Hangzhou 310006 (China); Department of Obstetrics and Gynaecology, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4 (Canada); Cheng, Jung-Chien [Department of Obstetrics and Gynaecology, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4 (Canada); Huang, He-Feng, E-mail: huanghefg@hotmail.com [Department of Reproductive Endocrinology, Women’s Hospital, School of Medicine, Zhejiang University, Hangzhou 310006 (China); Leung, Peter C.K., E-mail: peter.leung@ubc.ca [Department of Reproductive Endocrinology, Women’s Hospital, School of Medicine, Zhejiang University, Hangzhou 310006 (China); Department of Obstetrics and Gynaecology, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4 (Canada)

    2013-11-01

    Highlights: •HOXA7 regulates MCF7 cell proliferation. •HOXA7 up-regulates ERα expression. •HOXA7 mediates estrogen-induced MCF7 cell proliferation. -- Abstract: Breast cancer is the most common hormone-dependent malignancy in women. Homeobox (HOX) transcription factors regulate many cellular functions, including cell migration, proliferation and differentiation. The aberrant expression of HOX genes has been reported to be associated with human reproductive cancers. Estradiol (E2) and its nuclear receptors, estrogen receptor (ER)-alpha and ER-beta, are known to play critical roles in the regulation of breast cancer cell growth. However, an understanding of the potential relationship between HOXA7 and ER in breast cancer cells is limited. In this study, our results demonstrate that knockdown of HOXA7 in MCF7 cells significantly decreased cell proliferation and ERα expression. In addition, HOXA7 knockdown attenuated E2-induced cell proliferation as well as progesterone receptor (PR) expression. The stimulatory effects of E2 on cell proliferation and PR expression were abolished by co-treatment with ICI 182780, a selective ERα antagonist. In contrast, overexpression of HOXA7 significantly stimulated cell proliferation and ERα expression. Moreover, E2-induced cell proliferation, as well as PR expression, was enhanced by the overexpression of HOXA7. Neither knockdown nor overexpression of HOXA7 affected the ER-beta levels. Our results demonstrate a novel mechanistic role for HOXA7 in modulating breast cancer cell proliferation via regulation of ERα expression. This finding contributes to our understanding of the role HOXA7 plays in regulating the proliferation of ER-positive cancer cells.

  18. Identification of pyrogallol as an antiproliferative compound present in extracts from the medicinal plant Emblica officinalis: effects on in vitro cell growth of human tumor cell lines.

    Science.gov (United States)

    Khan, Mahmud Tareq Hassan; Lampronti, Ilaria; Martello, Dino; Bianchi, Nicoletta; Jabbar, Shaila; Choudhuri, Mohammad Shahabuddin Kabir; Datta, Bidduyt Kanti; Gambari, Roberto

    2002-07-01

    In this study we compared the in vitro antiproliferative activity of extracts from medicinal plants toward human tumor cell lines, including human erythromyeloid K562, B-lymphoid Raji, T-lymphoid Jurkat, erythroleukemic HEL cell lines. Extracts from Emblica officinalis were the most active in inhibiting in vitro cell proliferation, after comparison to those from Terminalia arjuna, Aphanamixis polystachya, Oroxylum indicum, Cuscuta reflexa, Aegle marmelos, Saraca asoka, Rumex maritimus, Lagerstroemia speciosa, Red Sandalwood. Emblica officinalis extracts have been studied previously, due to their hepatoprotective, antioxidant, antifungal, antimicrobial and anti-inflammatory medicinal activities. Gas chromatography/mass spectrometry analyses allowed to identify pyrogallol as the common compound present both in unfractionated and n-butanol fraction of Emblica officinalis extracts. Antiproliferative effects of pyrogallol were therefore determined on human tumor cell lines thus identifying pyrogallol as an active component of Emblica officinalis extracts.

  19. Armet, a UPR-upregulated protein, inhibits cell proliferation and ER stress-induced cell death

    International Nuclear Information System (INIS)

    Apostolou, Andria; Shen Yuxian; Liang Yan; Luo Jun; Fang Shengyun

    2008-01-01

    The accumulation of misfolded proteins in the endoplasmic reticulum (ER) causes ER stress that initiates the unfolded protein response (UPR). UPR activates both adaptive and apoptotic pathways, which contribute differently to disease pathogenesis. To further understand the functional mechanisms of UPR, we identified 12 commonly UPR-upregulated genes by expression microarray analysis. Here, we describe characterization of Armet/MANF, one of the 12 genes whose function was not clear. We demonstrated that the Armet/MANF protein was upregulated by various forms of ER stress in several cell lines as well as by cerebral ischemia of rat. Armet/MANF was localized in the ER and Golgi and was also a secreted protein. Silencing Armet/MANF by siRNA oligos in HeLa cells rendered cells more susceptible to ER stress-induced death, but surprisingly increased cell proliferation and reduced cell size. Overexpression of Armet/MANF inhibited cell proliferation and improved cell viability under glucose-free conditions and tunicamycin treatment. Based on its inhibitory properties for both proliferation and cell death we have demonstrated, Armet is, thus, a novel secreted mediator of the adaptive pathway of UPR

  20. Cell proliferation is a key determinant of the outcome of FOXO3a activation

    Energy Technology Data Exchange (ETDEWEB)

    Poulsen, Raewyn C., E-mail: raewyn.poulsen@gmail.com; Carr, Andrew J.; Hulley, Philippa A.

    2015-06-19

    The FOXO family of forkhead transcription factors have a pivotal role in determining cell fate in response to oxidative stress. FOXO activity can either promote cell survival or induce cell death. Increased FOXO-mediated cell death has been implicated in the pathogenesis of degenerative diseases affecting musculoskeletal tissues. The aim of this study was to determine the conditions under which one member of the FOXO family, FOXO3a, promotes cell survival as opposed to cell death. Treatment of primary human tenocytes with 1 pM hydrogen peroxide for 18 h resulted in increased protein levels of FOXO3a. In peroxide-treated cells cultured in low serum media, FOXO3a inhibited cell proliferation and protected against apoptosis. However in peroxide treated cells cultured in high serum media, cell proliferation was unchanged but level of apoptosis significantly increased. Similarly, in tenocytes transduced to over-express FOXO3a, cell proliferation was inhibited and level of apoptosis unchanged in cells cultured in low serum. However there was a robust increase in cell death in FOXO3a-expressing cells cultured in high serum. Inhibition of cell proliferation in either peroxide-treated or FOXO3a-expressing cells cultured in high serum protected against apoptosis induction. Conversely, addition of a Chk2 inhibitor to peroxide-treated or FOXO3a-expressing cells overrode the inhibitory effect of FOXO3a on cell proliferation and led to increased apoptosis in cells cultured in low serum. This study demonstrates that proliferating cells may be particularly susceptible to the apoptosis-inducing actions of FOXO3a. Inhibition of cell proliferation by FOXO3a may be a critical event in allowing the pro-survival rather than the pro-apoptotic activity of FOXO3a to prevail. - Highlights: • FOXO3a activity can result in either promotion of cell survival or apoptosis. • The outcome of FOXO3a activation differs in proliferating compared to non-proliferating cells. • Proliferating

  1. Cell proliferation is a key determinant of the outcome of FOXO3a activation

    International Nuclear Information System (INIS)

    Poulsen, Raewyn C.; Carr, Andrew J.; Hulley, Philippa A.

    2015-01-01

    The FOXO family of forkhead transcription factors have a pivotal role in determining cell fate in response to oxidative stress. FOXO activity can either promote cell survival or induce cell death. Increased FOXO-mediated cell death has been implicated in the pathogenesis of degenerative diseases affecting musculoskeletal tissues. The aim of this study was to determine the conditions under which one member of the FOXO family, FOXO3a, promotes cell survival as opposed to cell death. Treatment of primary human tenocytes with 1 pM hydrogen peroxide for 18 h resulted in increased protein levels of FOXO3a. In peroxide-treated cells cultured in low serum media, FOXO3a inhibited cell proliferation and protected against apoptosis. However in peroxide treated cells cultured in high serum media, cell proliferation was unchanged but level of apoptosis significantly increased. Similarly, in tenocytes transduced to over-express FOXO3a, cell proliferation was inhibited and level of apoptosis unchanged in cells cultured in low serum. However there was a robust increase in cell death in FOXO3a-expressing cells cultured in high serum. Inhibition of cell proliferation in either peroxide-treated or FOXO3a-expressing cells cultured in high serum protected against apoptosis induction. Conversely, addition of a Chk2 inhibitor to peroxide-treated or FOXO3a-expressing cells overrode the inhibitory effect of FOXO3a on cell proliferation and led to increased apoptosis in cells cultured in low serum. This study demonstrates that proliferating cells may be particularly susceptible to the apoptosis-inducing actions of FOXO3a. Inhibition of cell proliferation by FOXO3a may be a critical event in allowing the pro-survival rather than the pro-apoptotic activity of FOXO3a to prevail. - Highlights: • FOXO3a activity can result in either promotion of cell survival or apoptosis. • The outcome of FOXO3a activation differs in proliferating compared to non-proliferating cells. • Proliferating

  2. Musashi1 modulates cell proliferation genes in the medulloblastoma cell line Daoy

    Directory of Open Access Journals (Sweden)

    Hung Jaclyn Y

    2008-09-01

    Full Text Available Abstract Background Musashi1 (Msi1 is an RNA binding protein with a central role during nervous system development and stem cell maintenance. High levels of Msi1 have been reported in several malignancies including brain tumors thereby associating Msi1 and cancer. Methods We used the human medulloblastoma cell line Daoy as model system in this study to knock down the expression of Msi1 and determine the effects upon soft agar growth and neurophere formation. Quantitative RT-PCR was conducted to evaluate the expression of cell proliferation, differentiation and survival genes in Msi1 depleted Daoy cells. Results We observed that MSI1 expression was elevated in Daoy cells cultured as neurospheres compared to those grown as monolayer. These data indicated that Msi1 might be involved in regulating proliferation in cancer cells. Here we show that shRNA mediated Msi1 depletion in Daoy cells notably impaired their ability to form colonies in soft agar and to grow as neurospheres in culture. Moreover, differential expression of a group of Notch, Hedgehog and Wnt pathway related genes including MYCN, FOS, NOTCH2, SMO, CDKN1A, CCND2, CCND1, and DKK1, was also found in the Msi1 knockdown, demonstrating that Msi1 modulated the expression of a subset of cell proliferation, differentiation and survival genes in Daoy. Conclusion Our data suggested that Msi1 may promote cancer cell proliferation and survival as its loss seems to have a detrimental effect in the maintenance of medulloblastoma cancer cells. In this regard, Msi1 might be a positive regulator of tumor progression and a potential target for therapy.

  3. EEN regulates the proliferation and survival of multiple myeloma cells by potentiating IGF-1 secretion

    International Nuclear Information System (INIS)

    Huang, Er-Wen; Xue, Sheng-Jiang; Li, Xiao-Yan; Xu, Suo-Wen; Cheng, Jian-Ding; Zheng, Jin-Xiang; Shi, He; Lv, Guo-Li; Li, Zhi-Gang; Li, Yue; Liu, Chang-Hui; Chen, Xiao-Hui; Liu, Hong; Li, Jie; Liu, Chao

    2014-01-01

    Highlights: • Levels of EEN expression paralleled with the rate of cell proliferation. • EEN was involved in the proliferation and survival of multiple myeloma (MM) cells. • EEN regulated the activity of IGF-1-Akt/mTOR pathway. • EEN regulated proliferation and survival of MM cells by enhancing IGF-1 secretion. - Abstract: The molecular mechanisms of multiple myeloma are not well defined. EEN is an endocytosis-regulating molecule. Here we report that EEN regulates the proliferation and survival of multiple myeloma cells, by regulating IGF-1 secretion. In the present study, we observed that EEN expression paralleled with cell proliferation, EEN accelerated cell proliferation, facilitated cell cycle transition from G1 to S phase by regulating cyclin-dependent kinases (CDKs) pathway, and delayed cell apoptosis via Bcl2/Bax-mitochondrial pathway. Mechanistically, we found that EEN was indispensable for insulin-like growth factor-1 (IGF-1) secretion and the activation of protein kinase B-mammalian target of rapamycin (Akt-mTOR) pathway. Exogenous IGF-1 overcame the phenotype of EEN depletion, while IGF-1 neutralization overcame that of EEN over-expression. Collectively, these data suggest that EEN may play a pivotal role in excessive cell proliferation and insufficient cell apoptosis of bone marrow plasma cells in multiple myeloma. Therefore, EEN may represent a potential diagnostic marker or therapeutic target for multiple myeloma

  4. EEN regulates the proliferation and survival of multiple myeloma cells by potentiating IGF-1 secretion

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Er-Wen [Guangzhou Institute of Forensic Science, Guangzhou (China); Department of Forensic Pathology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou (China); Xue, Sheng-Jiang [Department of Forensic Pathology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou (China); Li, Xiao-Yan [Department of Pharmacy, The Third Affiliated Hospital, Sun Yat-Sen University, Guangzhou (China); Xu, Suo-Wen [Department of Pharmacology and Toxicology, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou (China); Cheng, Jian-Ding; Zheng, Jin-Xiang [Department of Forensic Pathology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou (China); Shi, He; Lv, Guo-Li; Li, Zhi-Gang; Li, Yue; Liu, Chang-Hui; Chen, Xiao-Hui; Liu, Hong [Guangzhou Institute of Forensic Science, Guangzhou (China); Li, Jie, E-mail: mdlijie@sina.com [Department of Anaesthesiology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou (China); Liu, Chao, E-mail: liuchaogaj@21cn.com [Guangzhou Institute of Forensic Science, Guangzhou (China)

    2014-05-02

    Highlights: • Levels of EEN expression paralleled with the rate of cell proliferation. • EEN was involved in the proliferation and survival of multiple myeloma (MM) cells. • EEN regulated the activity of IGF-1-Akt/mTOR pathway. • EEN regulated proliferation and survival of MM cells by enhancing IGF-1 secretion. - Abstract: The molecular mechanisms of multiple myeloma are not well defined. EEN is an endocytosis-regulating molecule. Here we report that EEN regulates the proliferation and survival of multiple myeloma cells, by regulating IGF-1 secretion. In the present study, we observed that EEN expression paralleled with cell proliferation, EEN accelerated cell proliferation, facilitated cell cycle transition from G1 to S phase by regulating cyclin-dependent kinases (CDKs) pathway, and delayed cell apoptosis via Bcl2/Bax-mitochondrial pathway. Mechanistically, we found that EEN was indispensable for insulin-like growth factor-1 (IGF-1) secretion and the activation of protein kinase B-mammalian target of rapamycin (Akt-mTOR) pathway. Exogenous IGF-1 overcame the phenotype of EEN depletion, while IGF-1 neutralization overcame that of EEN over-expression. Collectively, these data suggest that EEN may play a pivotal role in excessive cell proliferation and insufficient cell apoptosis of bone marrow plasma cells in multiple myeloma. Therefore, EEN may represent a potential diagnostic marker or therapeutic target for multiple myeloma.

  5. Homeostatic proliferation fails to efficiently reactivate HIV-1 latently infected central memory CD4+ T cells.

    Directory of Open Access Journals (Sweden)

    Alberto Bosque

    2011-10-01

    Full Text Available Homeostatic proliferation ensures the longevity of central memory T-cells by inducing cell proliferation in the absence of cellular differentiation or activation. This process is governed mainly by IL-7. Central memory T-cells can also be stimulated via engagement of the T-cell receptor, leading to cell proliferation but also activation and differentiation. Using an in vitro model of HIV-1 latency, we have examined in detail the effects of homeostatic proliferation on latently infected central memory T cells. We have also used antigenic stimulation via anti-CD3/anti-CD28 antibodies and established a comparison with a homeostatic proliferation stimulus, to evaluate potential differences in how either treatment affects the dynamics of latent virus populations. First, we show that homeostatic proliferation, as induced by a combination of IL-2 plus IL-7, leads to partial reactivation of latent HIV-1 but is unable to reduce the size of the reservoir in vitro. Second, latently infected cells are able to homeostatically proliferate in the absence of viral reactivation or cell differentiation. These results indicate that IL-2 plus IL-7 may induce a detrimental effect by favoring the maintenance of the latent HIV-1 reservoir. On the other hand, antigenic stimulation efficiently reactivated latent HIV-1 in cultured central memory cells and led to depletion of the latently infected cells via virus-induced cell death.

  6. Stimulation of cell proliferation by histamine H2 receptors in dimethylhdrazine-induced adenocarcinomata.

    Science.gov (United States)

    Tutton, P J; Barkla, D H

    1978-03-01

    Cell proliferation in dimethylhydrazine-induced colonic carcinomata was stimulated by histamine and by the histamine H2 receptor agonist dimaprit and inhibited by the histamine H2 receptor antagonists Metiamide and Cimetidine but not by the histamine H1 receptor antagonist Mepyramine. In contrast histamine had no effect on colonic crypt cell proliferation in normal or dimethylhydrazine-treated rats.

  7. Expression of Nanog gene promotes NIH3T3 cell proliferation

    International Nuclear Information System (INIS)

    Zhang Jingyu; Wang Xia; Chen Bing; Suo Guangli; Zhao Yanhong; Duan Ziyuan; Dai Jianwu

    2005-01-01

    Cells are the functional elements in tissue engineering and regenerative medicine. A large number of cells are usually needed for these purposes. However, there are numbers of limitations for in vitro cell proliferation. Nanog is an important self-renewal determinant in embryonic stem cells. However, it remains unknown whether Nanog will influence the cell cycle and cell proliferation of mature cells. In this study, we expressed Nanog in NIH3T3 cells and showed that expression of Nanog in NIH3T3 promoted cells to enter into S phase and enhanced cell proliferation. This suggests that Nanog gene might function in a similar fashion in mature cells as in ES cells. In addition, it may provide an approach for in vitro cell expansion

  8. Cadmium mimics estrogen-driven cell proliferation and prolactin secretion from anterior pituitary cells.

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    Sonia A Ronchetti

    Full Text Available Cadmium (Cd is a heavy metal of considerable occupational and environmental concern affecting wildlife and human health. Recent studies indicate that Cd, like other heavy metals, can mimic effects of 17β-estradiol (E2 involving E2 receptor (ER activation. Lactotrophs, the most abundant cell type in anterior pituitary gland, are the main target of E2, which stimulates cell proliferation and increases prolactin secretion through ERα. The aim of this work was to examine whether Cd at nanomolar concentrations can induce cell proliferation and prolactin release in anterior pituitary cells in culture and whether these effects are mediated through ERs. Here we show that 10 nM Cd was able to stimulate lactotroph proliferation in anterior pituitary cell cultures from female Wistar rats and also in GH3 lactosomatotroph cell line. Proliferation of somatotrophs and gonadotrophs were not affected by Cd exposure. Cd promoted cell cycle progression by increasing cyclins D1, D3 and c-fos expression. Cd enhanced prolactin synthesis and secretion. Cd E2-like effects were blocked by the pure ERs antagonist ICI 182,780 supporting that Cd acts through ERs. Further, both Cd and E2 augmented full-length ERαexpression and its 46 kDa-splicing variant. In addition, when co-incubated Cd was shown to interact with E2 by inducing ERα mRNA expression which indicates an additive effect between them. This study shows for the first time that Cd at nanomolar concentration displays xenoestrogenic activities by inducing cell growth and stimulating prolactin secretion from anterior pituitary cells in an ERs-dependent manner. Cd acting as a potent xenoestrogen can play a key role in the aetiology of different pathologies of the anterior pituitary and in estrogen-responsive tissues which represent considerable risk to human health.

  9. β-Catenin promotes cell proliferation, migration, and invasion but induces apoptosis in renal cell carcinoma

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    Yang CM

    2017-02-01

    Full Text Available Chun-ming Yang,1 Shan Ji,2 Yan Li,3 Li-ye Fu,3 Tao Jiang,3 Fan-dong Meng31Department of Urology, The First Affiliated Hospital, China Medical University, 2Department of Endocrinology, The Fifth People’s Hospital of Shenyang, 3Department of Biotherapy, Cancer Research Institute, The First Affiliated Hospital, China Medical University, Shenyang, ChinaAbstract: β-Catenin (CTNNB1 gene coding protein is a component of the Wnt signaling pathway that has been shown to play an important role in the formation of certain cancers. Abnormal accumulation of CTNNB1 contributes to most cancers. This research studied the involvement of β-catenin in renal cell carcinoma (RCC cell proliferation, apoptosis, migration, and invasion. Proliferation, cell cycle, and apoptosis were analyzed by using Cell Counting Kit-8 and by flow cytometry. Migration and invasion assays were measured by transwell analysis. Real-time polymerase chain reaction and Western blot analysis were used to detect the expression of CTNNB1, ICAM-1, VCAM-1, CXCR4, and CCL18 in RCC cell lines. It was found that CTNNB1 knockdown inhibited cell proliferation, migration, and invasion and induced apoptosis of A-498 cells. CTNNB1 overexpression promoted cell proliferation, migration, and invasion and inhibited apoptosis of 786-O cells. Moreover, knockdown of CTNNB1 decreased the levels of ICAM-1, VCAM-1, CXCR4, and CCL18 expression, but CTNNB1 overexpression increased the expression of ICAM-1, VCAM-1, CXCR4, and CCL18. Further in vivo tumor formation study in nude mice indicated that inhibition of CTNNB1 delayed the progress of tumor formation through inhibiting PCNA and Ki67 expression. These results indicate that CTNNB1 could act as an oncogene and may serve as a promising therapeutic strategy for RCC.Keywords: kidney cancer, oncogene, β-catenin, survival time, tumor migration-related protein

  10. Donor lung derived myeloid and plasmacytoid dendritic cells differentially regulate T cell proliferation and cytokine production

    Directory of Open Access Journals (Sweden)

    Benson Heather L

    2012-03-01

    Full Text Available Abstract Background Direct allorecognition, i.e., donor lung-derived dendritic cells (DCs stimulating recipient-derived T lymphocytes, is believed to be the key mechanism of lung allograft rejection. Myeloid (cDCs and plasmacytoid (pDCs are believed to have differential effects on T cell activation. However, the roles of each DC type on T cell activation and rejection pathology post lung transplantation are unknown. Methods Using transgenic mice and antibody depletion techniques, either or both cell types were depleted in lungs of donor BALB/c mice (H-2d prior to transplanting into C57BL/6 mice (H-2b, followed by an assessment of rejection pathology, and pDC or cDC-induced proliferation and cytokine production in C57BL/6-derived mediastinal lymph node T cells (CD3+. Results Depleting either DC type had modest effect on rejection pathology and T cell proliferation. In contrast, T cells from mice that received grafts depleted of both DCs did not proliferate and this was associated with significantly reduced acute rejection scores compared to all other groups. cDCs were potent inducers of IFNγ, whereas both cDCs and pDCs induced IL-10. Both cell types had variable effects on IL-17A production. Conclusion Collectively, the data show that direct allorecognition by donor lung pDCs and cDCs have differential effects on T cell proliferation and cytokine production. Depletion of both donor lung cDC and pDC could prevent the severity of acute rejection episodes.

  11. Ginger phytochemicals exhibit synergy to inhibit prostate cancer cell proliferation

    Science.gov (United States)

    Brahmbhatt, Meera; Gundala, Sushma R.; Asif, Ghazia; Shamsi, Shahab A; Aneja, Ritu

    2014-01-01

    Dietary phytochemicals offer non-toxic therapeutic management as well as chemopreventive intervention for slow-growing prostate cancers. However, the limited success of several single-agent clinical trials suggest a paradigm shift that the health benefits of fruits and vegetables are not ascribable due to individual phytochemicals rather may be ascribed to but to synergistic interactions among them. We recently reported growth-inhibiting and apoptosis-inducing properties of ginger extract (GE) in in vitro and in vivo prostate cancer models. Nevertheless, the nature of interactions among the constituent ginger biophenolics, viz. 6-gingerol, 8-gingerol, 10-gingerol, and 6-shogoal, remains elusive. Here we show antiproliferative efficacy of the most-active GE biophenolics as single-agents and in binary combinations, and investigate the nature of their interactions using the Chou-Talalay combination-index (CI) method. Our data demonstrate that binary combinations of ginger phytochemicals synergistically inhibit proliferation of PC-3 cells with CI values ranging from 0.03-0.88. To appreciate synergy among phytochemicals present in GE, the natural abundance of ginger biophenolics was quantitated using LC-UV/MS. Interestingly, combining GE with its constituents (in particular, 6-gingerol) resulted in significant augmentation of GE’s antiproliferative activity. These data generate compelling grounds for further preclinical evaluation of GE alone and in combination with individual ginger biophenols for prostate cancer management. PMID:23441614

  12. ETOH inhibits embryonic neural stem/precursor cell proliferation via PLD signaling

    International Nuclear Information System (INIS)

    Fujita, Yuko; Hiroyama, Masami; Sanbe, Atsushi; Yamauchi, Junji; Murase, Shoko; Tanoue, Akito

    2008-01-01

    While a mother's excessive alcohol consumption during pregnancy is known to have adverse effects on fetal neural development, little is known about the underlying mechanism of these effects. In order to investigate these mechanisms, we investigated the toxic effect of ethanol (ETOH) on neural stem/precursor cell (NSC) proliferation. In cultures of NSCs, phospholipase D (PLD) is activated following stimulation with epidermal growth factor (EGF) and fibroblast growth factor 2 (FGF2). Exposure of NSCs to ETOH suppresses cell proliferation, while it has no effect on cell death. Phosphatidic acid (PA), which is a signaling messenger produced by PLD, reverses ETOH inhibition of NSC proliferation. Blocking the PLD signal by 1-butanol suppresses the proliferation. ETOH-induced suppression of NSC proliferation and the protective effect of PA for ETOH-induced suppression are mediated through extracellular signal-regulated kinase signaling. These results indicate that exposure to ETOH impairs NSC proliferation by altering the PLD signaling pathway

  13. Effects of ultrasound on the proliferation and differentiation of cementoblast lineage cells

    NARCIS (Netherlands)

    Inubushi, T.; Tanaka, E.; Rego, E.B.; Kitagawa, M.; Kawazoe, A.; Ohta, A.; Okada, H.; Koolstra, J.H.; Miyauchi, M.; Takata, T.; Tanne, K.

    2008-01-01

    Background: The purpose of this study was to investigate the effects of low-intensity pulsed ultrasound (LIPUS) stimulation on the proliferation and differentiation of cementoblast lineage cells. Methods: An immortalized human periodontal ligament cell line (HPL) showing immature cementoblastic

  14. The effect of cerium valence states at cerium oxide nanoparticle surfaces on cell proliferation

    KAUST Repository

    Naganuma, Tamaki; Traversa, Enrico

    2014-01-01

    Understanding and controlling cell proliferation on biomaterial surfaces is critical for scaffold/artificial-niche design in tissue engineering. The mechanism by which underlying integrin ligates with functionalized biomaterials to induce cell

  15. Effect of hydroxyurea and vinblastine on the proliferation of the pluripotential stem cells

    International Nuclear Information System (INIS)

    Necas, E.; Neuwirt, J.

    1977-01-01

    The population of the pluripotential hemopoietic stem cells in mice, i.e., cells forming colonies in the spleens of lethally irradiated mice (colony forming cells CFc) proliferates relatively slowly. After partial damage the population regenerates which is achieved by an increased proliferation rate. The effect of damage caused by different doses of hydroxyurea or vinblastine to the proliferation of the CFc was investigated. CFc population was measured in femur bone marrow after the grafting of a bone marrow sample into lethally irradiated mice recipients (spleen colony method). The proliferation rate was estimated either according to the magnitude of the fraction of cells synthesizing DNA in the S phase of the cell cycle, or according to the sensitivity of the population to repeated injections of vinblastine. Data showed that even after very minute damage by hydroxyurea the stem cells started to proliferate intensively. The effect was dose dependent. The comparable damage caused by vinblastine had a significantly weaker effect on the proliferation of the stem cells. It is concluded from the results that the proliferation response of the pluripotential stem cells depends on two factors: the extent of the damage caused to the hemopoietic tissue and the position of the killed cells in the cell cycle. (author)

  16. Oxidized Lipoprotein as a Major Vessel Cell Proliferator in Oxidized Human Serum.

    Directory of Open Access Journals (Sweden)

    Yoshiro Saito

    Full Text Available Oxidative stress is correlated with the incidence of several diseases such as atherosclerosis and cancer, and oxidized biomolecules have been determined as biomarkers of oxidative stress; however, the detailed molecular relationship between generated oxidation products and the promotion of diseases has not been fully elucidated. In the present study, to clarify the role of serum oxidation products in vessel cell proliferation, which is related to the incidence of atherosclerosis and cancer, the major vessel cell proliferator in oxidized human serum was investigated. Oxidized human serum was prepared by free radical exposure, separated using gel chromatography, and then each fraction was added to several kinds of vessel cells including endothelial cells and smooth muscle cells. It was found that a high molecular weight fraction in oxidized human serum specifically induced vessel cell proliferation. Oxidized lipids were contained in this high molecular weight fraction, while cell proliferation activity was not observed in oxidized lipoprotein-deficient serum. Oxidized low-density lipoproteins induced vessel cell proliferation in a concentration-dependent manner. Taken together, these results indicate that oxidized lipoproteins containing lipid oxidation products function as a major vessel cell proliferator in oxidized human serum. These findings strongly indicate the relevance of determination of oxidized lipoproteins and lipid oxidation products in the diagnosis of vessel cell proliferation-related diseases such as atherosclerosis and cancer.

  17. 1,8-cineole inhibits both proliferation and elongation of BY-2 cultured tobacco cells.

    Science.gov (United States)

    Yoshimura, Hiroko; Sawai, Yu; Tamotsu, Satoshi; Sakai, Atsushi

    2011-03-01

    Volatile monoterpenes such as 1,8-cineole inhibit the growth of Brassica campestris seedlings in a dose-dependent manner, and the growth-inhibitory effects are more severe for roots than hypocotyls. The preferential inhibition of root growth may be explained if the compounds inhibit cell proliferation more severely than cell elongation because root growth requires both elongation and proliferation of the constituent cells, whereas hypocotyl growth depends exclusively on elongation of existing cells. In order to examine this possibility, BY-2 suspension-cultured tobacco (Nicotiana tabacum) cells were treated with 1,8-cineole, and the inhibitory effects on cell proliferation and on cell elongation were assessed quantitatively. Treatment with 1,8-cineole lowered both the mitotic index and elongation of the cells in a dose-dependent manner, and the half-maximal inhibitory concentration (IC₅₀) for cell elongation was lower than that for cell proliferation. Moreover, 1,8-cineole also inhibited starch synthesis, with IC₅₀ lower than that for cell proliferation. Thus, the inhibitory effects of 1,8-cineole were not specific to cell proliferation; rather, 1,8-cineole seemed inhibitory to a variety of physiological activities when it was in direct contact with target cells. Based on these results, possible mechanisms for the mode of action of 1,8-cineole and for its preferential inhibition on root growth are discussed.

  18. Collective cell migration without proliferation: density determines cell velocity and wave velocity

    Science.gov (United States)

    Tlili, Sham; Gauquelin, Estelle; Li, Brigitte; Cardoso, Olivier; Ladoux, Benoît; Delanoë-Ayari, Hélène; Graner, François

    2018-05-01

    Collective cell migration contributes to embryogenesis, wound healing and tumour metastasis. Cell monolayer migration experiments help in understanding what determines the movement of cells far from the leading edge. Inhibiting cell proliferation limits cell density increase and prevents jamming; we observe long-duration migration and quantify space-time characteristics of the velocity profile over large length scales and time scales. Velocity waves propagate backwards and their frequency depends only on cell density at the moving front. Both cell average velocity and wave velocity increase linearly with the cell effective radius regardless of the distance to the front. Inhibiting lamellipodia decreases cell velocity while waves either disappear or have a lower frequency. Our model combines conservation laws, monolayer mechanical properties and a phenomenological coupling between strain and polarity: advancing cells pull on their followers, which then become polarized. With reasonable values of parameters, this model agrees with several of our experimental observations. Together, our experiments and model disantangle the respective contributions of active velocity and of proliferation in monolayer migration, explain how cells maintain their polarity far from the moving front, and highlight the importance of strain-polarity coupling and density in long-range information propagation.

  19. Flow cytometric evaluation of the effects of 3-bromopyruvate (3BP) and dichloracetate (DCA) on THP-1 cells: a multiparameter analysis

    NARCIS (Netherlands)

    Verhoeven, H.A.; Griensven, van L.J.L.D.

    2012-01-01

    Two human leukemia cells K562 and THP-1, the breast cancer lines MCF-7 and ZR-75-1, and the melanoma line MDA-MB-435S were compared by flowcytometry for their behaviour at increasing levels of 3BP. K562 and THP-1 responded to 3BP by membrane depolarization and increased ROS; MCF-7 and ZR-75-1 showed

  20. [Role of connective tissue growth factor (CTGF) in proliferation and migration of pancreatic cancer cells].

    Science.gov (United States)

    Bai, Yu-chun; Kang, Quan; Luo, Qing; Wu, Dao-qi; Ye, Wei-xia; Lin, Xue-mei; Zhao, Yong

    2011-10-01

    To explore the expression of connective tissue growth factor (CTGF) in pancreatic cancer and its influence on the proliferation and migration of cancer cells. The expression of CTGF in pancreatic cell line PANC-1 cells was analyzed by real-time PCR and in pancreatic carcinoma (50 cases) tissues by immunohistochemistry. The ability of proliferation and migration in vitro of PANC-1 cells was tested by MTT assay, scratch test and Boyden chamber test after the CTGF gene was overexpressed by Ad5-CTGF or silenced with Ad5-siCTGF transfection. CTGF was overexpressed in both pancreatic cancer cells and tissues. Overxpression of CTGF leads to increased proliferation and migration of PANC-1 cells. The CTGF-transfected PANC-1 cells showed apparent stronger proliferation ability and scratch-repair ability than that of empty vector controls. The results of Boyden chamber test showed that there were 34 cells/field (200× magnificantion) of the CTGF-transfected overexpressing cells, much more than the 11 cells/field of the empty vector control cells; and 6 cells/microscopic field of the Ad5-siCTGF-transfected silenced cells, much less than the 15 cells/field of the control cells. CTGF is overexpressed in both pancreatic cancer cells in vitro and in vivo, indicating that it may play an important role in the cell proliferation and migration in pancreatic cancer.

  1. Effects of Monoclonal Antibody Cetuximab on Proliferation of Non-small Cell Lung Cancer Cell lines

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    Zhen CHEN

    2010-08-01

    Full Text Available Background and objective The epidermal growth factor receptor (EGFR monoclonal antibody cetuximab has been used widely in non-small cell lung cancer patients. The aim of this study is to explore the effect of lung cancer cells (A549, H460, H1299, SPC-A-1 which were treated by cetuximab in vitro. Methods We studied the effects of increasing concentrations of cetuximab (1 nmol/L-625 nmol/L in four human lung cancer cell lines (A549, SPC-A-1, H460, H1229. CCK8 measured the inhibition of cell proliferation in each group. A549, SPC-A-1 were marked by PI and the statuses of apoptosis were observed. Western blot were used to detect the proliferation-related signaling protein and apoptosis-related protein in A549. Results The treatment with cetuximab resulted in the effect on cell proliferation and apoptosis in a time- and dosedependent manner. The expression of activated key enzymes (p-AKT, p-EGFR, p-MAPK in EGFR signaling transduction pathway were down-regulated more obviously. Conclusion Cetuximab is an effective targeted drug in the treatment of lung cancer cell lines, tissues, most likely to contribute to the inhibition of key enzymes in EGFR signaling transduction pathway.

  2. Cell culture density affects the proliferation activity of human adipose tissue stem cells.

    Science.gov (United States)

    Kim, Dae Seong; Lee, Myoung Woo; Ko, Young Jong; Chun, Yong Hoon; Kim, Hyung Joon; Sung, Ki Woong; Koo, Hong Hoe; Yoo, Keon Hee

    2016-01-01

    In this study, we investigated the effect of cell density on the proliferation activity of human mesenchymal stem cells (MSCs) derived from adipose tissue (AT-MSCs) over time in culture. Passage #4 (P4) and #12 (P12) AT-MSCs from two donors were plated at a density of 200 (culture condition 1, CC1) or 5000 (culture condition 2, CC2) cells cm(-2) . After 7 days of incubation, P4 and P12 AT-MSCs cultured in CC1 were thin and spindle-shaped, whereas those cultured in CC2 had extensive cell-to-cell contacts and an expanded cell volume. In addition, P4 and P12 AT-MSCs in CC1 divided more than three times, while those in CC2 divided less than once on average. Flow cytometric analysis using 5(6)-carboxyfluorescein diacetate N-succinimidyl ester dye showed that the fluorescence intensity of AT-MSCs was lower in CC1 than in CC2. Furthermore, expression of proliferation-associated genes, such as CDC45L, CDC20A and KIF20A, in P4 AT-MSCs was higher in CC1 than in CC2, and this difference was also observed in P12 AT-MSCs. These data demonstrated that cell culture density affects the proliferation activity of MSCs, suggesting that it is feasible to design a strategy to prepare suitable MSCs using specific culture conditions. Copyright © 2016 John Wiley & Sons, Ltd.

  3. Proliferation of mouse endometrial stromal cells in culture is highly sensitive to lysophosphatidic acid signaling

    International Nuclear Information System (INIS)

    Aikawa, Shizu; Kano, Kuniyuki; Inoue, Asuka; Aoki, Junken

    2017-01-01

    Endometrial stromal cells (ESCs) proliferate rapidly both in vivo and in vitro. Here we show that proliferation of ESCs in vitro is strongly dependent on lysophosphatidic acid (LPA) signaling. LPA is produced by autotaxin (ATX) and induces various kinds of cellular processes including migration, proliferation and inhibition of cell death possibly through six G protein-coupled receptors (LPA 1-6 ). We found that ESCs proliferated rapidly in vitro in an autocrine manner and that the proliferation was prominently suppressed by either an ATX inhibitor (ONO-8430506) or an LPA 1/3 antagonist (Ki16425). Among the cells lines tested, mouse ESCs were the most sensitive to these inhibitors. Proliferation of ESCs isolated from either LPA 1 - or LPA 3 -deficient mice was comparable to proliferation of ESCs isolated from control mice. An LPA receptor antagonist (AM095), which was revealed to be a dual LPA 1 /LPA 3 antagonist, also suppressed the proliferation of ESCs. The present results show that LPA signaling has a critical role in the proliferation of ESCs, and that this role is possibly mediated redundantly by LPA 1 and LPA 3 . - Highlights: • Uterine endometrial stromal cells (ESCs) proliferate rapidly both in vivo and in vitro. • ESCs proliferated in vitro in an autocrine fashion. • Proliferation of mouse ESCs was prominently suppressed by inhibitors of lysophosphatidic acid (LPA) signaling. • LPA receptors, LPA 1 and LPA 3 , had redundant role in supporting the proliferation of ESCs.

  4. Bevacizumab inhibits proliferation of choroidal endothelial cells by regulation of the cell cycle.

    Science.gov (United States)

    Rusovici, Raluca; Patel, Chirag J; Chalam, Kakarla V

    2013-01-01

    The purpose of this study was to evaluate cell cycle changes in choroidal endothelial cells treated with varying doses of bevacizumab in the presence of a range of concentrations of vascular endothelial growth factor (VEGF). Bevacizumab, a drug widely used in the treatment of neovascular age-related macular degeneration, choroidal neovascularization, and proliferative diabetic retinopathy, neutralizes all isoforms of VEGF. However, the effect of intravitreal administration of bevacizumab on the choroidal endothelial cell cycle has not been established. Monkey choroidal endothelial (RF/6A) cells were treated with VEGF 50 ng/mL and escalating doses of bevacizumab 0.1-2 mg/mL for 72 hours. Cell cycle changes in response to bevacizumab were analyzed by flow cytometry and propidium iodide staining. Cell proliferation was measured using the WST-1 assay. Morphological changes were recorded by bright field cell microscopy. Bevacizumab inhibited proliferation of choroidal endothelial cells by stabilization of the cell cycle in G0/G1 phase. Cell cycle analysis of VEGF-enriched choroidal endothelial cells revealed a predominant increase in the G2/M population (21.84%, P, 0.01) and a decrease in the G0/G1 phase population (55.08%, P, 0.01). Addition of escalating doses of bevacizumab stabilized VEGF-enriched cells in the G0/G1 phase (55.08%, 54.49%, 56.3%, and 64% [P, 0.01]) and arrested proliferation by inhibiting the G2/M phase (21.84%, 21.46%, 20.59%, 20.94%, and 16.1% [P, 0.01]). The increase in G0/G1 subpopulation in VEGF-enriched and bevacizumab-treated cells compared with VEGF-enriched cells alone was dose-dependent. Bevacizumab arrests proliferation of VEGF-enriched choroidal endothelial cells by stabilizing the cell cycle in the G0/G1 phase and inhibiting the G2/M phase in a dose-dependent fashion.

  5. [Inhibitory effect of 17-AAG combined with paclitaxel on proliferation of esophageal squamous cell carcinoma Eca-109 cells in vitro].

    Science.gov (United States)

    Chen, Size; Chen, Xuemei; Li, Yuqi; Yang, Shu; Mo, Xianyi; Zhang, Fan; Mo, Kailan; Ding, Ying

    2015-06-01

    To investigate the effect of 17-AAG combined with paclitaxel (PTX) on the proliferation and apoptosis of esophageal squamous cell carcinoma cell line Eca-109 in vitro. Eca-109 cells were treated with 17-AAG and PTX either alone or in combination. The proliferation of Eca-109 cells was detected by MTT assay, and the cell cycle changes and cell apoptosis were determined by flow cytometry. Compared with the control group, both 17-AAG and PTX significantly inhibited the proliferation of Eca-109 cells. A combined treatment of the cells with 0.5 µmol/L PTX and 0.625 µmol/L 17-AAG produced an obviously stronger inhibitory effect on the cell proliferation than either of the agents used alone (PAAG and PTX used alone caused Eca-109 cell cycle arrest in G2/M phase and S phase, respectively, and their combined use caused cell cycle arrest in both G2/M and S phases. The cell apoptosis rates of Eca-109 cells treated with 17-AAG, PTX and their combination were 4.52%, 10.91%, and 29.88%, respectively, all significantly higher than that in the control group (1.32%); the combined treatment resulted in a distinct apoptotic peak that was significantly higher than that caused by either of the agents alone. 17-AAG and PTX can inhibit cell proliferation and promote apoptosis of Eca-109 cells, and their combination produces stronger effects in inhibiting cell proliferation and increasing cell apoptosis.

  6. Interaction of osteoblast-like cells with serum and fibronectin: effects on cell motility and proliferation in vitro

    International Nuclear Information System (INIS)

    Zuk, A.

    1986-01-01

    Osteoblast migration and proliferation are believed to occur during bone remodelling, in particular after osteoclastic bone resorption and prior to osteoblastic bone formation. In order to study migration and proliferation in vitro, the model of Alessandri et al. (1983) was modified. The model entailed seeding osteoblast-like cells into wells cut in agar and quantifying migration and proliferation peripheral to the well. Cell morphology also was described. The data indicated that on growth surfaces enriched with varying concentrations of fetal calf serum (FSC), the quantification of migration and proliferation was related both to percent cell attachment and to FCS-concentration. Because few osteoblast-like cells incorporated ( 3 H-TdR), it was concluded that the appearance of cells peripheral to the well was due to migration, and not to proliferation. Cell morphology and myosin distribution and organization indicated that osteoblast-like cells at the periphery of the cell culture (i.e. leading edge) may have been directionally migrating whereas cells behind the leading edge may have been engaged in non-directional migration. The migration, proliferation, and morphology of osteoblast-like cells cultured on fibronectin (FN) enriched growth surfaces also was examined. The quantification of migration and proliferation was related to the FN-concentration applied to the growth surface. Because few osteoblast-like cells incorporated 3 H-TdR and cell morphology indicated migration, it was concluded that osteoblast-like cells on FN-enriched growth surfaces are specialized, in part, for migration

  7. Suppression of lymphocyte proliferation by marijuana components is related to cell number and cell source

    International Nuclear Information System (INIS)

    Klein, T.; Pross, S.; Newton, C.; Friedman, H.

    1986-01-01

    Conflicting reports have appeared concerning the effect of marijuana components on immune responsiveness. The authors have observed that the effect of cannabinoids on lymphocyte proliferation varied with both the concentration of the drug and the mitogen used. They now report that at a constant concentration of drug, the cannabinoid effect varied from no effect to suppression depending upon the number of cells in culture and the organ source of the cells. Dispersed cell suspensions of mouse lymph node, spleen, and thymus were prepared and cultured at varying cell numbers with either delta-9-tetrahydrocannabinol or 11-hydroxy-delta-9-tetrahydrocannabinol and various mitogens. Lymphocyte proliferation was analyzed by 3 H-thymidine incorporation. T-lymphocyte mitogen responses in cultures containing high cell numbers were unaffected by the cannabinoids but as cell numbers were reduced a suppression of the response was observed. Furthermore, thymus cells were considerably more susceptible to cannabinoid suppression than cells from either lymph node or spleen. These results suggest that certain lymphocyte subpopulations are more sensitive to cannabinoid suppression and that in addition to drug concentration other variables such as cell number and cell source must be considered when analyzing cannabinoid effects

  8. The insulin-like growth factors I and II stimulate proliferation of different types of Schwann cells

    DEFF Research Database (Denmark)

    Sondell, M; Svenningsen, Åsa Fex; Kanje, M

    1997-01-01

    in combination with BrdU immunocytochemistry showed that around 93% of the proliferating cells in the nerve segments were Schwann cells. Immunostaining for BrdU and GFAP (glial fibrillary acid protein) showed that IGF-II enhanced proliferation of Schwann cells surrounding unmyelinated nerve fibres. In contrast......, truncated IGF-I promoted proliferation of Schwann cells of myelinated nerve fibres while insulin increased proliferation of both cell types....

  9. Cell proliferation in dimethylhydrazine-induced colonic adenocarcinomata following cytotoxic drug treatment.

    Science.gov (United States)

    Tutton, P J; Barkla, D H

    1978-08-25

    A stathmokinetic technique was used to study cell proliferation in dimethylhydrazine-induced adenocarcinomata of rat colon following treatment with cytotoxic drugs. The rate of cell division was significantly increased three days after treatment with 5,7-dihydroxytryptamine and seven days after treatment with 5-fluorouracil. Acceleration of tumour cell proliferation following 5,7-dihydroxytryptamine treatment was inhibited by treating animals with the antiseritoninergic drug Xylamidine Tosylate. Acceleration of tumour cell proliferation following 5-fluorouracil treatment was inhibited by treating animals either with the antiseritoninergic drug BW501 or with the histamine H2-receptor blocking drug Cimetidine.

  10. Effects of nanostructurized silicon on proliferation of stem and cancer cell.

    Science.gov (United States)

    Osminkina, L A; Luckyanova, E N; Gongalsky, M B; Kudryavtsev, A A; Gaydarova, A Kh; Poltavtseva, R A; Kashkarov, P K; Timoshenko, V Yu; Sukhikh, G T

    2011-05-01

    In vitro experiments showed that stem and cancer cells retained their viability on the surface of porous silicon with 10-100 nm nanostructures, but their proliferation was inhibited. Silicon nanoparticles of 100 nm in size obtained by mechanical grinding of porous silicon films or crystal silicon plates in a concentration below 1 mg/ml in solution did not modify viability and proliferation of mouse fibroblast and human laryngeal cancer cells. Additional ultrasonic exposure of cancer cells in the presence of 1 mg/ml silicon nanoparticles added to nutrient medium led to complete destruction of cells or to the appearance of membrane defects blocking their proliferation and initiating their apoptotic death.

  11. [Autologous regulatory T cells can suppress the proliferation of lymphoma cell line in vitro].

    Science.gov (United States)

    Ying, Zhi-Tao; Guo, Jun; Ren, Jun; Kong, Yan; Yuan, Zhi-Hong; Liu, Xi-Juan; Zhang, Chen; Zheng, Wen; Song, Yu-Qin; Zhang, Yun-Tao; Zhu, Jun

    2009-06-01

    This study was aimed to investigate the suppressive effect of regulatory T (Treg) cells on the T cell lymphoma EL4 cell line and to explore its mechanism. C57BL/6 Mouse Treg cells were isolated by MACS (magnetic cell sorting). The purity and the expression of Foxp3 were detected by flow cytometry. The suppressive effect of sorted Treg cells on EL4 cells was detected by MTT assay. The secretion of TGF-beta1 and IL-10 was examined by enzyme-linked immunosorbent assay (ELISA). The results showed that CD4(+)CD25(+) T cells could be successfully isolated by MACS with the purity reaching 91.6% and the expression level of Foxp3 was 78.9%. The ratio of viable cells was more than 95%. Regulatory T cells could suppress the proliferation of EL4 cells effectively in the presence of antigen presenting cells (APCs). And the suppressive effect was most significant at 1:1 ratio. In addition, the suppression still existed without APCs. TGF-beta1 and IL-10 could not be detected by ELISA. It is concluded that the Treg cells can suppress T lymphoma cell in vitro. The suppressive effect of Treg cells works in dose-dependent manner, but not in cytokine-dependent manner. The mechanism of this suppression may take effect through cell-cell contact.

  12. Dafachronic acid inhibits C. elegans germ cell proliferation in a DAF-12-dependent manner.

    Science.gov (United States)

    Mukherjee, Madhumati; Chaudhari, Snehal N; Balachandran, Riju S; Vagasi, Alexandra S; Kipreos, Edward T

    2017-12-15

    Dafachronic acid (DA) is a bile acid-like steroid hormone that regulates dauer formation, heterochrony, and lifespan in C. elegans. Here, we describe that DA is an inhibitor of C. elegans germ stem cell proliferation in adult hermaphrodites. Using a C. elegans germ cell primary culture system, we show that DA inhibits the proliferation of germ cells in vitro. Exogenous DA reduces the frequency of large tumors in adult tumorous germline mutants and decreases the proliferation of wild-type germ stem cells in adult hermaphrodites. In contrast, DA has no appreciable effect on the proliferation of larval-stage germ cells in wild type. The inhibition of adult germ cell proliferation by DA requires its canonical receptor DAF-12. Blocking DA production by inactivating the cytochrome P450 DAF-9 increases germ cell proliferation in wild-type adult hermaphrodites and the frequency of large tumors in germline tumorous mutants, suggesting that DA inhibits the rate of germ cell proliferation under normal growth conditions. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Zinc Promotes Adipose-Derived Mesenchymal Stem Cell Proliferation and Differentiation towards a Neuronal Fate.

    Science.gov (United States)

    Moon, Mi-Young; Kim, Hyun Jung; Choi, Bo Young; Sohn, Min; Chung, Tae Nyoung; Suh, Sang Won

    2018-01-01

    Zinc is an essential element required for cell division, migration, and proliferation. Under zinc-deficient conditions, proliferation and differentiation of neural progenitors are significantly impaired. Adipose-derived mesenchymal stem cells (AD-MSCs) are multipotent stem cells that can differentiate into neurons. The aim of this study was to evaluate the effect of zinc on AD-MSC proliferation and differentiation. We initially examined the effect of zinc on stem cell proliferation at the undifferentiated stage. AD-MSCs showed high proliferation rates on day 6 in 30  μ M and 100  μ M of ZnCl 2 . Zinc chelation inhibited AD-MSC proliferation via downregulation of ERK1/2 activity. We then assessed whether zinc was involved in cell migration and neurite outgrowth during differentiation. After three days of neuronal differentiation, TUJ-1-positive cells were observed, implying that AD-MSCs had differentiated into early neuron or neuron-like cells. Neurite outgrowth was increased in the zinc-treated group, while the CaEDTA-treated group showed diminished, shrunken neurites. Furthermore, we showed that zinc promoted neurite outgrowth via the inactivation of RhoA and led to the induction of neuronal gene expression (MAP2 and nestin) in differentiated stem cells. Taken together, zinc promoted AD-MSC proliferation and affected neuronal differentiation, mainly by increasing neurite outgrowth.

  14. Zinc Promotes Adipose-Derived Mesenchymal Stem Cell Proliferation and Differentiation towards a Neuronal Fate

    Directory of Open Access Journals (Sweden)

    Mi-Young Moon

    2018-01-01

    Full Text Available Zinc is an essential element required for cell division, migration, and proliferation. Under zinc-deficient conditions, proliferation and differentiation of neural progenitors are significantly impaired. Adipose-derived mesenchymal stem cells (AD-MSCs are multipotent stem cells that can differentiate into neurons. The aim of this study was to evaluate the effect of zinc on AD-MSC proliferation and differentiation. We initially examined the effect of zinc on stem cell proliferation at the undifferentiated stage. AD-MSCs showed high proliferation rates on day 6 in 30 μM and 100 μM of ZnCl2. Zinc chelation inhibited AD-MSC proliferation via downregulation of ERK1/2 activity. We then assessed whether zinc was involved in cell migration and neurite outgrowth during differentiation. After three days of neuronal differentiation, TUJ-1-positive cells were observed, implying that AD-MSCs had differentiated into early neuron or neuron-like cells. Neurite outgrowth was increased in the zinc-treated group, while the CaEDTA-treated group showed diminished, shrunken neurites. Furthermore, we showed that zinc promoted neurite outgrowth via the inactivation of RhoA and led to the induction of neuronal gene expression (MAP2 and nestin in differentiated stem cells. Taken together, zinc promoted AD-MSC proliferation and affected neuronal differentiation, mainly by increasing neurite outgrowth.

  15. Mesenchymal precursor cells maintain the differentiation and proliferation potentials of breast epithelial cells

    Science.gov (United States)

    2014-01-01

    Introduction Stromal-epithelial interactions play a fundamental role in tissue homeostasis, controlling cell proliferation and differentiation. Not surprisingly, aberrant stromal-epithelial interactions contribute to malignancies. Studies of the cellular and molecular mechanisms underlying these interactions require ex vivo experimental model systems that recapitulate the complexity of human tissue without compromising the differentiation and proliferation potentials of human primary cells. Methods We isolated and characterized human breast epithelial and mesenchymal precursors from reduction mammoplasty tissue and tagged them with lentiviral vectors. We assembled heterotypic co-cultures and compared mesenchymal and epithelial cells to cells in corresponding monocultures by analyzing growth, differentiation potentials, and gene expression profiles. Results We show that heterotypic culture of non-immortalized human primary breast epithelial and mesenchymal precursors maintains their proliferation and differentiation potentials and constrains their growth. We further describe the gene expression profiles of stromal and epithelial cells in co-cultures and monocultures and show increased expression of the tumor growth factor beta (TGFβ) family member inhibin beta A (INHBA) in mesenchymal cells grown as co-cultures compared with monocultures. Notably, overexpression of INHBA in mesenchymal cells increases colony formation potential of epithelial cells, suggesting that it contributes to the dynamic reciprocity between breast mesenchymal and epithelial cells. Conclusions The described heterotypic co-culture system will prove useful for further characterization of the molecular mechanisms mediating interactions between human normal or neoplastic breast epithelial cells and the stroma, and will provide a framework to test the relevance of the ever-increasing number of oncogenomic alterations identified in human breast cancer. PMID:24916766

  16. Testicular Sertoli cells influence the proliferation and immunogenicity of co-cultured endothelial cells

    International Nuclear Information System (INIS)

    Fan, Ping; He, Lan; Pu, Dan; Lv, Xiaohong; Zhou, Wenxu; Sun, Yining; Hu, Nan

    2011-01-01

    Research highlights: → The proliferation of dramatic increased by co-cultured with Sertoli cells. → VEGF receptor-2 expression of ECs was up-regulated by co-cultured with Sertoli cells. → The MHC expression of ECs induced by INF-γ and IL-6, IL-8 and sICAM induced by TNF-α decreased respectively after co-cultured with Sertoli cells. → ECs co-cultured with Sertoli cells also didn't increase the stimulation index of spleen lymphocytes. -- Abstract: The major problem of the application of endothelial cells (ECs) in transplantation is the lack of proliferation and their immunogenicity. In this study, we co-cultured ECs with Sertoli cells to monitor whether Sertoli cells can influence the proliferation and immunogenicity of co-cultured ECs. Sertoli cells were isolated from adult testicular tissue. ECs were divided into the control group and the experimental group, which included three sub-groups co-cultured with 1 x 10 3 , 1 x 10 4 or 1 x 10 5 cell/ml of Sertoli cells. The growth and proliferation of ECs were observed microscopically, and the expression of vascular endothelial growth factor (VEGF) receptor-2 (KDR) was examined by Western blotting. In another experiment, ECs were divided into the control group, the single culture group and the co-culture group with the optimal concentration of Sertoli cells. After INF-γ and TNF-α were added to the culture medium, MHC II antigen expression was detected by immunofluorescence staining and western blotting; interleukin (IL)-6, IL-8 and soluble intercellular adhesion molecule (sICAM) were measured in the culture medium by ELISA. We demonstrated that 1 x 10 4 cell/ml Sertoli cells promoted the proliferation of co-cultured ECs more dramatically than that in other groups (P 4 cell/ml of the Sertoli cells was most effective in the up-regulation of KDR expression in the co-cultured ECs (P < 0.05). Sertoli cells can effectively suppress INF-γ-induced MHC II antigen expression in co-cultured ECs compared with single

  17. Slug/SNAI2 regulates cell proliferation and invasiveness of metastatic prostate cancer cell lines.

    Science.gov (United States)

    Emadi Baygi, Modjtaba; Soheili, Zahra-Soheila; Essmann, Frank; Deezagi, Abdolkhaleg; Engers, Rainer; Goering, Wolfgang; Schulz, Wolfgang A

    2010-08-01

    Many metastatic cancers recapitulate the epithelial-to-mesenchymal transition (EMT) resulting in enhanced cell motility and invasiveness. The EMT is regulated by several transcription factors, including the zinc finger protein SNAI2, also named Slug, which appears to exert additional functions during development and cancer progression. We have studied the function of SNAI2 in prostate cancer cells. Quantitative RT-PCR analysis showed strong SNAI2 expression particularly in the PC-3 and PC3-16 prostate carcinoma cell lines. Knockdown of SNAI2 by specific siRNA induced changes in EMT markers and inhibited invasion of both cell lines into a matrigel matrix. SNAI2 siRNA-treated cells did not tolerate detachment from the culture plates, likely at least in part due to downregulation of integrin alpha6beta4. SNAI2 knockdown disturbed the microtubular and actin cytoskeletons, especially severely in PC-3 cells, resulting in grossly enlarged, flattened, and sometimes multinuclear cells. Knockdown also decreased cell proliferation, with a prominent G0/G1 arrest in PC3-16. Together, our data imply that SNAI2 exerts strong effects on the cytoskeleton and adhesion of those prostate cancer cells that express it and is necessary for their proliferation and invasiveness.

  18. Eosinophils from hematopoietic stem cell recipients suppress allogeneic T cell proliferation.

    Science.gov (United States)

    Andersson, Jennie; Cromvik, Julia; Ingelsten, Madeleine; Lingblom, Christine; Andersson, Kerstin; Johansson, Jan-Erik; Wennerås, Christine

    2014-12-01

    Eosinophilia has been associated with less severe graft-versus-host disease (GVHD), but the underlying mechanism is unknown. We hypothesized that eosinophils diminish allogeneic T cell activation in patients with chronic GVHD. The capacity of eosinophils derived from healthy subjects and hematopoietic stem cell (HSC) transplant recipients, with or without chronic GVHD, to reduce allogeneic T cell proliferation was evaluated using a mixed leukocyte reaction. Eosinophil-mediated inhibition of proliferation was observed for the eosinophils of both healthy subjects and patients who underwent HSC transplantation. Eosinophils from patients with and without chronic GVHD were equally suppressive. Healthy eosinophils required cell-to-cell contact for their suppressive capacity, which was directed against CD4(+) T cells and CD8(+) T cells. Neither eosinophilic cationic protein, eosinophil-derived neurotoxin, indoleamine 2,3-dioxygenase, or increased numbers of regulatory T cells could account for the suppressive effect of healthy eosinophils. Real-time quantitative PCR analysis revealed significantly increased mRNA levels of the immunoregulatory protein galectin-10 in the eosinophils of both chronic GVHD patients and patients without GVHD, as compared with those from healthy subjects. The upregulation of galectin-10 expression in eosinophils from patients suggests a stimulatory effect of HSC transplantation in itself on eosinophilic galectin-10 expression, regardless of chronic GVHD status. To conclude, eosinophils from HSC transplant recipients and healthy subjects have a T cell suppressive capacity. Copyright © 2014 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

  19. Discoidin domain receptor 2 (DDR2) regulates proliferation of endochondral cells in mice

    International Nuclear Information System (INIS)

    Kawai, Ikuma; Hisaki, Tomoka; Sugiura, Koji; Naito, Kunihiko; Kano, Kiyoshi

    2012-01-01

    Highlights: ► Discoidin domain receptor 2 (DDR2) is a receptor tyrosine kinase. ► DDR2 regulates cell proliferation, cell adhesion, migration, and extracellular matrix remodeling. ► We produced in vitro and in vivo model to better understand the role of DDR2. ► DDR2 might play an inhibitory role in the proliferation of chondrocyte. -- Abstract: Discoidin domain receptor 2 (DDR2) is a receptor tyrosine kinase that is activated by fibrillar collagens. DDR2 regulates cell proliferation, cell adhesion, migration, and extracellular matrix remodeling. The decrement of endogenous DDR2 represses osteoblastic marker gene expression and osteogenic differentiation in murine preosteoblastic cells, but the functions of DDR2 in chondrogenic cellular proliferation remain unclear. To better understand the role of DDR2 signaling in cellular proliferation in endochondral ossification, we inhibited Ddr2 expression via the inhibitory effect of miRNA on Ddr2 mRNA (miDdr2) and analyzed the cellular proliferation and differentiation in the prechondrocyte ATDC5 cell lines. To investigate DDR2’s molecular role in endochondral cellular proliferation in vivo, we also produced transgenic mice in which the expression of truncated, kinase dead (KD) DDR2 protein is induced, and evaluated the DDR2 function in cellular proliferation in chondrocytes. Although the miDdr2-transfected ATDC5 cell lines retained normal differentiation ability, DDR2 reduction finally promoted cellular proliferation in proportion to the decreasing ratio of Ddr2 expression, and it also promoted earlier differentiation to cartilage cells by insulin induction. The layer of hypertrophic chondrocytes in KD Ddr2 transgenic mice was not significantly thicker than that of normal littermates, but the layer of proliferative chondrocytes in KD-Ddr2 transgenic mice was significantly thicker than that of normal littermates. Taken together, our data demonstrated that DDR2 might play a local and essential role in the

  20. Discoidin domain receptor 2 (DDR2) regulates proliferation of endochondral cells in mice

    Energy Technology Data Exchange (ETDEWEB)

    Kawai, Ikuma; Hisaki, Tomoka; Sugiura, Koji; Naito, Kunihiko [Laboratory of Applied Genetics, Graduate School of Agricultural and Life Science, University of Tokyo, Tokyo 113-8657 (Japan); Kano, Kiyoshi, E-mail: kanokiyo@yamaguchi-u.ac.jp [Laboratory of Developmental Biology, Joint Faculty of Veterinary Medicine, Yamaguchi University, Yamaguchi 753-8515, Japan. (Japan); Biomedical Science Center for Translational Research (BSCTR), The United Graduate School of Veterinary Science, Yamaguchi University, Yamaguchi 753-8515 (Japan)

    2012-10-26

    Highlights: Black-Right-Pointing-Pointer Discoidin domain receptor 2 (DDR2) is a receptor tyrosine kinase. Black-Right-Pointing-Pointer DDR2 regulates cell proliferation, cell adhesion, migration, and extracellular matrix remodeling. Black-Right-Pointing-Pointer We produced in vitro and in vivo model to better understand the role of DDR2. Black-Right-Pointing-Pointer DDR2 might play an inhibitory role in the proliferation of chondrocyte. -- Abstract: Discoidin domain receptor 2 (DDR2) is a receptor tyrosine kinase that is activated by fibrillar collagens. DDR2 regulates cell proliferation, cell adhesion, migration, and extracellular matrix remodeling. The decrement of endogenous DDR2 represses osteoblastic marker gene expression and osteogenic differentiation in murine preosteoblastic cells, but the functions of DDR2 in chondrogenic cellular proliferation remain unclear. To better understand the role of DDR2 signaling in cellular proliferation in endochondral ossification, we inhibited Ddr2 expression via the inhibitory effect of miRNA on Ddr2 mRNA (miDdr2) and analyzed the cellular proliferation and differentiation in the prechondrocyte ATDC5 cell lines. To investigate DDR2's molecular role in endochondral cellular proliferation in vivo, we also produced transgenic mice in which the expression of truncated, kinase dead (KD) DDR2 protein is induced, and evaluated the DDR2 function in cellular proliferation in chondrocytes. Although the miDdr2-transfected ATDC5 cell lines retained normal differentiation ability, DDR2 reduction finally promoted cellular proliferation in proportion to the decreasing ratio of Ddr2 expression, and it also promoted earlier differentiation to cartilage cells by insulin induction. The layer of hypertrophic chondrocytes in KD Ddr2 transgenic mice was not significantly thicker than that of normal littermates, but the layer of proliferative chondrocytes in KD-Ddr2 transgenic mice was significantly thicker than that of normal littermates

  1. Newly identified interfibrillar collagen crosslinking suppresses cell proliferation and remodelling.

    Science.gov (United States)

    Marelli, Benedetto; Le Nihouannen, Damien; Hacking, S Adam; Tran, Simon; Li, Jingjing; Murshed, Monzur; Doillon, Charles J; Ghezzi, Chiara E; Zhang, Yu Ling; Nazhat, Showan N; Barralet, Jake E

    2015-06-01

    Copper is becoming recognised as a key cation in a variety of biological processes. Copper chelation has been studied as a potential anti-angiogenic strategy for arresting tumour growth. Conversely the delivery of copper ions and complexes in vivo can elicit a pro-angiogenic effect. Previously we unexpectedly found that copper-stimulated intraperitoneal angiogenesis was accompanied by collagen deposition. Here, in hard tissue, not only was healing accelerated by copper, but again enhanced deposition of collagen was detected at 2 weeks. Experiments with reconstituted collagen showed that addition of copper ions post-fibrillogenesis rendered plastically-compressed gels resistant to collagenases, enhanced their mechanical properties and increased the denaturation temperature of the protein. Unexpectedly, this apparently interfibrillar crosslinking was not affected by addition of glucose or ascorbic acid, which are required for crosslinking by advanced glycation end products (AGEs). Fibroblasts cultured on copper-crosslinked gels did not proliferate, whereas those cultured with an equivalent quantity of copper on either tissue culture plastic or collagen showed no effect compared with controls. Although non-proliferative, fibroblasts grown on copper-cross-linked collagen could migrate, remained metabolically active for at least 14 days and displayed a 6-fold increase in Mmps 1 and 3 mRNA expression compared with copper-free controls. The ability of copper ions to crosslink collagen fibrils during densification and independently of AGEs or Fenton type reactions is previously unreported. The effect on MMP susceptibility of collagen and the dramatic change in cell behaviour on this crosslinked ECM may contribute to shedding some light on unexplained phenomena as the apparent benefit of copper complexation in fibrotic disorders or the enhanced collagen deposition in response to localised copper delivery. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Cell density and N-cadherin interactions regulate cell proliferation in the sensory epithelia of the inner ear.

    Science.gov (United States)

    Warchol, Mark E

    2002-04-01

    Sensory hair cells in the inner ears of nonmammalian vertebrates can regenerate after injury. In many species, replacement hair cells are produced by the proliferation of epithelial supporting cells. Thus, the ability of supporting cells to undergo renewed proliferation is a key determinant of regenerative ability. The present study used cultures of isolated inner ear sensory epithelia to identify cellular signals that regulate supporting cell proliferation. Small pieces of sensory epithelia from the chicken utricle were cultured in glass microwells. Under those conditions, cell proliferation was inversely related to local cell density. The signaling molecules N-cadherin, beta-catenin, and focal adhesion kinase were immunolocalized in the cultured epithelial cells, and high levels of phosphotyrosine immunoreactivity were present at cell-cell junctions and focal contacts of proliferating cells. Binding of microbeads coated with a function-blocking antibody to N-cadherin inhibited ongoing proliferation. The growth of epithelial cells was also affected by the density of extracellular matrix molecules. The results suggest that cell density, cell-cell contact, and the composition of the extracellular matrix may be critical influences on the regulation of sensory regeneration in the inner ear.

  3. Effects of Src on Proliferation and Invasion of Lung Cancer Cells

    Directory of Open Access Journals (Sweden)

    Rui ZHENG

    2011-04-01

    Full Text Available Background and objective It has been proven that Src played pivotal roles in carcinogenesis, cancer progression and metastasis. The aim of this study is to explore the roles of Src phosphorylation on lung cancer cells. Methods Western blot and immunoprecipitation was used to detect the expression and phosphorylation of Src in lung cancer cells. MTT and Boyden chamber assay was used to examine the effects of inhibition of Src phosphorylation on proliferation and invasion of lung cancer cells in vitro, respectively. Results pp60src was expressed in all lung cancer cell lines in this study. All 5 non-small cell lung cancer (NSCLC cell lines had increased autophosphorylated tyrosine-418, while nearly no phosphorylated Src in small cell lung cancer SBC5 cell line was detected. The effect of inhibition of Src tyrosine kinase on cell proliferation varied among the lung cancer cell lines. Submicromolar Src tyrosine kinase inhibitor (≤1 μM remarkably suppressed the proliferation of PC-9 and A549 cells in a dose dependent manner (P < 0.05, while the same concentration of Src tyrosine kinase inhibitor had no significant effect on proliferation of H226, PC14PE6 and RERFLCOK cells. Invasiveness of lung cancer cells was significantly suppressed by Src tyrosine kinase in a dose-dependent manner (P < 0.05. Conclusion Phosphorylation of Src, but not over-expression, plays a pivotal role in proliferation and invasion of NSCLC cell lines in vitro.

  4. Δ9-Tetrahydrocannabinol enhances MCF-7 cell proliferation via cannabinoid receptor-independent signaling

    International Nuclear Information System (INIS)

    Takeda, Shuso; Yamaori, Satoshi; Motoya, Erina; Matsunaga, Tamihide; Kimura, Toshiyuki; Yamamoto, Ikuo; Watanabe, Kazuhito

    2008-01-01

    We recently reported that Δ 9 -tetrahydrocannabinol (Δ 9 -THC) has the ability to stimulate the proliferation of human breast carcinoma MCF-7 cells. However, the mechanism of action remains to be clarified. The present study focused on the relationship between receptor expression and the effects of Δ 9 -THC on cell proliferation. RT-PCR analysis demonstrated that there was no detectable expression of CB receptors in MCF-7 cells. In accordance with this, no effects of cannabinoid 1/2 (CB1/2) receptor antagonists and pertussis toxin on cell proliferation were observed. Although MCF-7 cell proliferation is suggested to be suppressed by Δ 9 -THC in the presence of CB receptors, it was revealed that Δ 9 -THC could exert upregulation of living cells in the absence of the receptors. Interestingly, Δ 9 -THC upregulated human epithelial growth factor receptor type 2 (HER2) expression, which is known to be a predictive factor of human breast cancer and is able to stimulate cancer cells as well as MCF-7 cells. Actinomycin D-treatment interfered with the upregulation of HER2 and cell proliferation by cannabinoid. Taken together, these studies suggest that, in the absence of CB receptors, Δ 9 -THC can stimulate the proliferation of MCF-7 cells by modulating, at least in part, HER2 transcription

  5. Phenolic Compounds in Extra Virgin Olive Oil Stimulate Human Osteoblastic Cell Proliferation

    Science.gov (United States)

    García-Martínez, Olga; De Luna-Bertos, Elvira; Ramos-Torrecillas, Javier; Ruiz, Concepción; Milia, Egle; Lorenzo, María Luisa; Jimenez, Brigida; Sánchez-Ortiz, Araceli; Rivas, Ana

    2016-01-01

    In this study, we aimed to clarify the effects of phenolic compounds and extracts from different extra virgin olive oil (EVOO) varieties obtained from fruits of different ripening stages on osteoblast cells (MG-63) proliferation. Cell proliferation was increased by hydroxytyrosol, luteolin, apigenin, p-coumaric, caffeic, and ferulic acids by approximately 11–16%, as compared with controls that were treated with one vehicle alone, while (+)-pinoresinol, oleuropein, sinapic, vanillic acid and derivative (vanillin) did not affect cell proliferation. All phenolic extracts stimulated MG-63 cell growth, and they induced higher cell proliferation rates than individual compounds. The most effective EVOO phenolic extracts were those obtained from the Picual variety, as they significantly increased cell proliferation by 18–22%. Conversely, Arbequina phenolic extracts increased cell proliferation by 9–13%. A decline in osteoblast proliferation was observed in oils obtained from olive fruits collected at the end of the harvest period, as their total phenolic content decreases at this late stage. Further research on the signaling pathways of olive oil phenolic compounds involved in the processes and their metabolism should be carried out to develop new interventions and adjuvant therapies using EVOO for bone health (i.e.osteoporosis) in adulthood and the elderly. PMID:26930190

  6. Phenolic Compounds in Extra Virgin Olive Oil Stimulate Human Osteoblastic Cell Proliferation.

    Science.gov (United States)

    García-Martínez, Olga; De Luna-Bertos, Elvira; Ramos-Torrecillas, Javier; Ruiz, Concepción; Milia, Egle; Lorenzo, María Luisa; Jimenez, Brigida; Sánchez-Ortiz, Araceli; Rivas, Ana

    2016-01-01

    In this study, we aimed to clarify the effects of phenolic compounds and extracts from different extra virgin olive oil (EVOO) varieties obtained from fruits of different ripening stages on osteoblast cells (MG-63) proliferation. Cell proliferation was increased by hydroxytyrosol, luteolin, apigenin, p-coumaric, caffeic, and ferulic acids by approximately 11-16%, as compared with controls that were treated with one vehicle alone, while (+)-pinoresinol, oleuropein, sinapic, vanillic acid and derivative (vanillin) did not affect cell proliferation. All phenolic extracts stimulated MG-63 cell growth, and they induced higher cell proliferation rates than individual compounds. The most effective EVOO phenolic extracts were those obtained from the Picual variety, as they significantly increased cell proliferation by 18-22%. Conversely, Arbequina phenolic extracts increased cell proliferation by 9-13%. A decline in osteoblast proliferation was observed in oils obtained from olive fruits collected at the end of the harvest period, as their total phenolic content decreases at this late stage. Further research on the signaling pathways of olive oil phenolic compounds involved in the processes and their metabolism should be carried out to develop new interventions and adjuvant therapies using EVOO for bone health (i.e.osteoporosis) in adulthood and the elderly.

  7. Slow and sustained nitric oxide releasing compounds inhibit multipotent vascular stem cell proliferation and differentiation without causing cell death

    Energy Technology Data Exchange (ETDEWEB)

    Curtis, Brandon M.; Leix, Kyle Alexander [Department of Chemistry, Central Michigan University, Mount Pleasant, MI 48859 (United States); Ji, Yajing [Department of Biomedical Science and Medicine, Michigan State University, East Lansing, MI 48824 (United States); Glaves, Richard Samuel Elliot [Department of Biology, Central Michigan University, Mount Pleasant, MI 48859 (United States); Ash, David E. [Department of Chemistry, Central Michigan University, Mount Pleasant, MI 48859 (United States); Mohanty, Dillip K., E-mail: Mohan1dk@cmich.edu [Department of Chemistry, Central Michigan University, Mount Pleasant, MI 48859 (United States)

    2014-07-18

    Highlights: • Multipotent vascular stem cells (MVSCs) proliferate and differentiate. • Nitric oxide inhibits proliferation of MVSCs. • Nitric oxide inhibits MVSC differentiation to mesenchymal-like stem cells (MSCs). • Smooth muscle cells (SMCs) neither de-differentiate nor proliferate. - Abstract: Atherosclerosis is the leading cause of cerebral and myocardial infarction. It is believed that neointimal growth common in the later stages of atherosclerosis is a result of vascular smooth muscle cell (SMC) de-differentiation in response to endothelial injury. However, the claims of the SMC de-differentiation theory have not been substantiated by monitoring the fate of mature SMCs in response to such injuries. A recent study suggests that atherosclerosis is a consequence of multipotent vascular stem cell (MVSC) differentiation. Nitric oxide (NO) is a well-known mediator against atherosclerosis, in part because of its inhibitory effect on SMC proliferation. Using three different NO-donors, we have investigated the effects of NO on MVSC proliferation. Results indicate that NO inhibits MVSC proliferation in a concentration dependent manner. A slow and sustained delivery of NO proved to inhibit proliferation without causing cell death. On the other hand, larger, single-burst NO concentrations, inhibits proliferation, with concurrent significant cell death. Furthermore, our results indicate that endogenously produced NO inhibits MVSC differentiation to mesenchymal-like stem cells (MSCs) and subsequently to SMC as well.

  8. Slow and sustained nitric oxide releasing compounds inhibit multipotent vascular stem cell proliferation and differentiation without causing cell death

    International Nuclear Information System (INIS)

    Curtis, Brandon M.; Leix, Kyle Alexander; Ji, Yajing; Glaves, Richard Samuel Elliot; Ash, David E.; Mohanty, Dillip K.

    2014-01-01

    Highlights: • Multipotent vascular stem cells (MVSCs) proliferate and differentiate. • Nitric oxide inhibits proliferation of MVSCs. • Nitric oxide inhibits MVSC differentiation to mesenchymal-like stem cells (MSCs). • Smooth muscle cells (SMCs) neither de-differentiate nor proliferate. - Abstract: Atherosclerosis is the leading cause of cerebral and myocardial infarction. It is believed that neointimal growth common in the later stages of atherosclerosis is a result of vascular smooth muscle cell (SMC) de-differentiation in response to endothelial injury. However, the claims of the SMC de-differentiation theory have not been substantiated by monitoring the fate of mature SMCs in response to such injuries. A recent study suggests that atherosclerosis is a consequence of multipotent vascular stem cell (MVSC) differentiation. Nitric oxide (NO) is a well-known mediator against atherosclerosis, in part because of its inhibitory effect on SMC proliferation. Using three different NO-donors, we have investigated the effects of NO on MVSC proliferation. Results indicate that NO inhibits MVSC proliferation in a concentration dependent manner. A slow and sustained delivery of NO proved to inhibit proliferation without causing cell death. On the other hand, larger, single-burst NO concentrations, inhibits proliferation, with concurrent significant cell death. Furthermore, our results indicate that endogenously produced NO inhibits MVSC differentiation to mesenchymal-like stem cells (MSCs) and subsequently to SMC as well

  9. Titanium phosphate glass microcarriers induce enhanced osteogenic cell proliferation and human mesenchymal stem cell protein expression

    Directory of Open Access Journals (Sweden)

    Nilay J Lakhkar

    2015-11-01

    Full Text Available In this study, we have developed 50- to 100-µm-sized titanium phosphate glass microcarriers (denoted as Ti5 that show enhanced proliferation of human mesenchymal stem cells and MG63 osteosarcoma cells, as well as enhanced human mesenchymal stem cell expression of bone differentiation markers, in comparison with commercially available glass microspheres at all time points. We also demonstrate that these microcarriers provide superior human mesenchymal stem cell proliferation with conventional Dulbecco’s Modified Eagle medium than with a specially developed commercial stem cell medium. The microcarrier proliferative capacity is revealed by a 24-fold increase in MG63 cell numbers in spinner flask bioreactor studies performed over a 7-day period, versus only a 6-fold increase in control microspheres under the same conditions; the corresponding values of Ti5 and control microspheres under static culture are 8-fold and 7-fold, respectively. The capability of guided osteogenic differentiation is confirmed by ELISAs for bone morphogenetic protein-2 and osteopontin, which reveal significantly greater expression of these markers, especially osteopontin, by human mesenchymal stem cells on the Ti5 microspheres than on the control. Scanning electron microscopy and confocal laser scanning microscopy images reveal favorable MG63 and human mesenchymal stem cell adhesion on the Ti5 microsphere surfaces. Thus, the results demonstrate the suitability of the developed microspheres for use as microcarriers in bone tissue engineering applications.

  10. Protease-activated receptor 2 agonist increases cell proliferation and invasion of human pancreatic cancer cells

    Science.gov (United States)

    XIE, LIQUN; DUAN, ZEXING; LIU, CAIJU; ZHENG, YANMIN; ZHOU, JING

    2015-01-01

    The aim of this study was to determine the expression of protease-activated receptor 2 (PAR-2) in the human pancreatic cancer cell line SW1990, and to evaluate its effect on cell proliferation and invasion. The expression of PAR-2 protein and mRNA in SW1990 cells was determined by immunocytochemistry and reverse transcription polymerase chain reaction (PCR), respectively. MTT and cell invasion and migration assays, as well as semi-quantitative PCR and zymography analysis, were additionally performed. PAR-2 mRNA was significantly upregulated in the cells treated with trypsin or the PAR-2 activating peptide Ser-Leu-Ile-Gly-Lys-Val (SLIGKV) (P0.05). Trypsin and SLIGKV significantly promoted SW1990 cell proliferation in a dose- and time-dependent manner (P<0.05). Compared with the control group, trypsin and SLIGKV significantly increased the mRNA expression (P<0.01) and gelatinolytic activity (P<0.01) of matrix metalloproteinase (MMP)-2. In conclusion, PAR-2 is expressed in SW1990 cells. PAR-2 activation may promote the invasion and migration of human pancreatic cancer cells by increasing MMP-2 expression. PMID:25452809

  11. Antibiotic drug tigecycline inhibited cell proliferation and induced autophagy in gastric cancer cells

    International Nuclear Information System (INIS)

    Tang, Chunling; Yang, Liqun; Jiang, Xiaolan; Xu, Chuan; Wang, Mei; Wang, Qinrui; Zhou, Zhansong; Xiang, Zhonghuai; Cui, Hongjuan

    2014-01-01

    Highlights: • Tigecycline inhibited cell growth and proliferation in human gastric cancer cells. • Tigecycline induced autophagy not apoptosis in human gastric cancer cells. • AMPK/mTOR/p70S6K pathway was activated after tigecycline treatment. • Tigecycline inhibited tumor growth in xenograft model of human gastric cancer cells. - Abstract: Tigecycline acts as a glycylcycline class bacteriostatic agent, and actively resists a series of bacteria, specifically drug fast bacteria. However, accumulating evidence showed that tetracycline and their derivatives such as doxycycline and minocycline have anti-cancer properties, which are out of their broader antimicrobial activity. We found that tigecycline dramatically inhibited gastric cancer cell proliferation and provided an evidence that tigecycline induced autophagy but not apoptosis in human gastric cancer cells. Further experiments demonstrated that AMPK pathway was activated accompanied with the suppression of its downstream targets including mTOR and p70S6K, and ultimately induced cell autophagy and inhibited cell growth. So our data suggested that tigecycline might act as a candidate agent for pre-clinical evaluation in treatment of patients suffering from gastric cancer

  12. Antibiotic drug tigecycline inhibited cell proliferation and induced autophagy in gastric cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Chunling; Yang, Liqun; Jiang, Xiaolan [State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400716 (China); Xu, Chuan [Division of Scientific Research and Training, General Hospital of PLA Chengdu Military Area Command, Chengdu, Sichuan 610083 (China); Wang, Mei; Wang, Qinrui [State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400716 (China); Zhou, Zhansong, E-mail: zhouzhans@sina.com [Institute of Urinary Surgery, Southwest Hospital, Third Military Medical University, Chongqing 400038 (China); Xiang, Zhonghuai [State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400716 (China); Cui, Hongjuan, E-mail: hcui@swu.edu.cn [State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400716 (China)

    2014-03-28

    Highlights: • Tigecycline inhibited cell growth and proliferation in human gastric cancer cells. • Tigecycline induced autophagy not apoptosis in human gastric cancer cells. • AMPK/mTOR/p70S6K pathway was activated after tigecycline treatment. • Tigecycline inhibited tumor growth in xenograft model of human gastric cancer cells. - Abstract: Tigecycline acts as a glycylcycline class bacteriostatic agent, and actively resists a series of bacteria, specifically drug fast bacteria. However, accumulating evidence showed that tetracycline and their derivatives such as doxycycline and minocycline have anti-cancer properties, which are out of their broader antimicrobial activity. We found that tigecycline dramatically inhibited gastric cancer cell proliferation and provided an evidence that tigecycline induced autophagy but not apoptosis in human gastric cancer cells. Further experiments demonstrated that AMPK pathway was activated accompanied with the suppression of its downstream targets including mTOR and p70S6K, and ultimately induced cell autophagy and inhibited cell growth. So our data suggested that tigecycline might act as a candidate agent for pre-clinical evaluation in treatment of patients suffering from gastric cancer.

  13. Programmed cell death-10 enhances proliferation and protects malignant T cells from apoptosis

    DEFF Research Database (Denmark)

    Lauenborg, Britt; Kopp, Katharina; Krejsgaard, Thorbjørn

    2010-01-01

    is associated with serine/threonine kinases and phosphatases and modulates the extracellular signal-regulated kinase pathway suggesting a role in the regulation of cellular growth. Here we provide evidence of a constitutive expression of PDCD10 in malignant T cells and cell lines from peripheral blood......, whereas an activator of Jak3 and NF-¿B, interleukin-2 (IL-2), enhances PDCD10 expression. Functional data show that PDCD10 depletion by small interfering RNA induces apoptosis and decreases proliferation of the sensitive cells. To our knowledge, these data provide the first functional link between PDCD10...

  14. Modulating Estrogen Receptor-related Receptor-α Activity Inhibits Cell Proliferation*

    OpenAIRE

    Bianco, Stéphanie; Lanvin, Olivia; Tribollet, Violaine; Macari, Claire; North, Sophie; Vanacker, Jean-Marc

    2009-01-01

    High expression of the estrogen receptor-related receptor (ERR)-α in human tumors is correlated to a poor prognosis, suggesting an involvement of the receptor in cell proliferation. In this study, we show that a synthetic compound (XCT790) that modulates the activity of ERRα reduces the proliferation of various cell lines and blocks the G1/S transition of the cell cycle in an ERR...

  15. Human Nanog pseudogene8 promotes the proliferation of gastrointestinal cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Uchino, Keita, E-mail: uchino13@intmed1.med.kyushu-u.ac.jp [Department of Medicine and Biosystemic Science, Kyushu University Graduate School of Medical Sciences, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan); Hirano, Gen [Department of Medicine and Biosystemic Science, Kyushu University Graduate School of Medical Sciences, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan); Hirahashi, Minako [Department of Anatomic Pathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Isobe, Taichi; Shirakawa, Tsuyoshi; Kusaba, Hitoshi; Baba, Eishi [Department of Medicine and Biosystemic Science, Kyushu University Graduate School of Medical Sciences, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan); Tsuneyoshi, Masazumi [Department of Anatomic Pathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Akashi, Koichi [Department of Medicine and Biosystemic Science, Kyushu University Graduate School of Medical Sciences, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan)

    2012-09-10

    There is emerging evidence that human solid tumor cells originate from cancer stem cells (CSCs). In cancer cell lines, tumor-initiating CSCs are mainly found in the side population (SP) that has the capacity to extrude dyes such as Hoechst 33342. We found that Nanog is expressed specifically in SP cells of human gastrointestinal (GI) cancer cells. Nucleotide sequencing revealed that NanogP8 but not Nanog was expressed in GI cancer cells. Transfection of NanogP8 into GI cancer cell lines promoted cell proliferation, while its inhibition by anti-Nanog siRNA suppressed the proliferation. Immunohistochemical staining of primary GI cancer tissues revealed NanogP8 protein to be strongly expressed in 3 out of 60 cases. In these cases, NanogP8 was found especially in an infiltrative part of the tumor, in proliferating cells with Ki67 expression. These data suggest that NanogP8 is involved in GI cancer development in a fraction of patients, in whom it presumably acts by supporting CSC proliferation. -- Highlights: Black-Right-Pointing-Pointer Nanog maintains pluripotency by regulating embryonic stem cells differentiation. Black-Right-Pointing-Pointer Nanog is expressed in cancer stem cells of human gastrointestinal cancer cells. Black-Right-Pointing-Pointer Nucleotide sequencing revealed that Nanog pseudogene8 but not Nanog was expressed. Black-Right-Pointing-Pointer Nanog pseudogene8 promotes cancer stem cells proliferation. Black-Right-Pointing-Pointer Nanog pseudogene8 is involved in gastrointestinal cancer development.

  16. Y-27632, a ROCK Inhibitor, Promoted Limbal Epithelial Cell Proliferation and Corneal Wound Healing.

    Directory of Open Access Journals (Sweden)

    Chi-Chin Sun

    Full Text Available Transplantation of ex vivo cultured limbal epithelial cells is proven effective in restoring limbal stem cell deficiency. The present study aimed to investigate the promoting effect of Y-27632 on limbal epithelial cell proliferation. Limbal explants isolated from human donor eyes were expanded three weeks on culture dishes and outgrowth of epithelial cells was subsequently subcultured for in vitro experiments. In the presence of Y-27632, the ex vivo limbal outgrowth was accelerated, particularly the cells with epithelial cell-like morphology. Y-27632 dose-dependently promoted the proliferation of in vitro cultured human limbal epithelial cells as examined by phase contrast microscopy and luminescent cell-viability assay 30 hours after the treatment. The colony forming efficacy determined 7 days after the treatment was enhanced by Y-27632 also in a dose-dependent manner. The number of p63- or Ki67-positive cells was dose-dependently increased in Y-27632-treated cultures as detected by immunofluorescent staining and western blotanalysis. Cell cycle analysis by flow cytometric method revealed an increase in S-phase proliferating cells. The epithelial woundclosure rate was shown to be faster in experimental group received topical treatment withY-27632 than the sham control using a rat corneal wounding model. These resultsdemonstrate that Y-27632 can promote both the ex vivo and in vitro proliferation oflimbal epithelial cell proliferation. The in vivo enhanced epithelial wound healingfurther implies that the Y-27632 may act as a new strategy for treating limbal stem cell deficiency.

  17. Human Nanog pseudogene8 promotes the proliferation of gastrointestinal cancer cells

    International Nuclear Information System (INIS)

    Uchino, Keita; Hirano, Gen; Hirahashi, Minako; Isobe, Taichi; Shirakawa, Tsuyoshi; Kusaba, Hitoshi; Baba, Eishi; Tsuneyoshi, Masazumi; Akashi, Koichi

    2012-01-01

    There is emerging evidence that human solid tumor cells originate from cancer stem cells (CSCs). In cancer cell lines, tumor-initiating CSCs are mainly found in the side population (SP) that has the capacity to extrude dyes such as Hoechst 33342. We found that Nanog is expressed specifically in SP cells of human gastrointestinal (GI) cancer cells. Nucleotide sequencing revealed that NanogP8 but not Nanog was expressed in GI cancer cells. Transfection of NanogP8 into GI cancer cell lines promoted cell proliferation, while its inhibition by anti-Nanog siRNA suppressed the proliferation. Immunohistochemical staining of primary GI cancer tissues revealed NanogP8 protein to be strongly expressed in 3 out of 60 cases. In these cases, NanogP8 was found especially in an infiltrative part of the tumor, in proliferating cells with Ki67 expression. These data suggest that NanogP8 is involved in GI cancer development in a fraction of patients, in whom it presumably acts by supporting CSC proliferation. -- Highlights: ► Nanog maintains pluripotency by regulating embryonic stem cells differentiation. ► Nanog is expressed in cancer stem cells of human gastrointestinal cancer cells. ► Nucleotide sequencing revealed that Nanog pseudogene8 but not Nanog was expressed. ► Nanog pseudogene8 promotes cancer stem cells proliferation. ► Nanog pseudogene8 is involved in gastrointestinal cancer development.

  18. NGF induces adult stem Leydig cells to proliferate and differentiate during Leydig cell regeneration.

    Science.gov (United States)

    Zhang, Lei; Wang, Huaxi; Yang, Yan; Liu, Hui; Zhang, Qihao; Xiang, Qi; Ge, Renshan; Su, Zhijian; Huang, Yadong

    2013-06-28

    Nerve growth factor (NGF) has been reported to be involved in male reproductive physiology. However, few reports have described the activity of NGF during Leydig cell development. The objective of the present study was to examine the role of NGF during stem-Leydig-cell (SLC) regeneration. We investigated the effects of NGF on Leydig-cell (LC) regeneration by measuring mRNA levels in the adult rat testis after ethane dimethanesulfonate (EDS) treatment. Furthermore, we used the established organ culture model of rat seminiferous tubules to examine the regulation of NGF during SLC proliferation and differentiation using EdU staining, real-time PCR and western blotting. Progenitor Leydig cells (PLCs) and immature Leydig cells (ILCs) were also used to investigate the effects of NGF on LCs at different developmental stages. NGF mRNA levels changed significantly during Leydig-cell regeneration in vivo. In vitro, NGF significantly promoted the proliferation of stem Leydig cells and also induced steroidogenic enzyme gene expression and 3β-HSD protein expression. The data from PLCs and ILCs showed that NGF could increase Cyclin D1 and Hsd 17b3 mRNA levels in PLCs and Cyclin D1 mRNA levels in ILCs. These results indicate that NGF may play an important role during LC regeneration by regulating the proliferation and differentiation of LCs at different developmental stages, from SLCs to PLCs and from PLCs to ILCs. The discovery of this effect of NGF on Leydig cells will provide useful information for developing new potential therapies for PADAM (Partial Androgen Deficiency in the Aging Male). Copyright © 2013 Elsevier Inc. All rights reserved.

  19. Intraepidermal proliferation of Merkel cells within a seborrheic keratosis: Merkel cell carcinoma in situ or Merkel cell hyperplasia?

    Science.gov (United States)

    McFalls, Jeanne; Okon, Lauren; Cannon, Sarah; Lee, Jason B

    2017-05-01

    Intradepidermal proliferation of Merkel cells without any dermal component has been interpreted as either a hyperplastic process secondary to chronic ultraviolet radiation or a neoplastic process, namely Merkel cell carcinoma (MCC) in situ. The recent criteria that have been proffered to diagnose MCC in situ, unfortunately, are identical to those that have been applied to Merkel cell hyperplasia in the past, posing a diagnostic quandary when faced with an intraepidermal proliferation of Merkel cells. Most previously reported cases of MCC in situ have occurred within associated epithelial lesion that includes solar (actinic) keratosis and squamous-cell carcinoma in situ. Similarly, Merkel cell hyperplasia has been reported to occur in association with a variety of epithelial lesions as well as on chronically sun-damaged skin. Herein, a case of an intraepidermal proliferation of Merkel cells within a seborrheic keratosis is presented accompanied by a discussion on whether the proliferation represents another case of Merkel cell carcinoma in situ or an incidental hyperplastic process on chronically sun-damaged skin. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  20. Adipose-derived mesenchymal stem cells promote cell proliferation and invasion of epithelial ovarian cancer

    Energy Technology Data Exchange (ETDEWEB)

    Chu, Yijing; Tang, Huijuan; Guo, Yan; Guo, Jing; Huang, Bangxing; Fang, Fang; Cai, Jing, E-mail: caijingmmm@hotmail.com; Wang, Zehua, E-mail: zehuawang@163.net

    2015-09-10

    Adipose-derived mesenchymal stem cell (ADSC) is an important component of tumor microenvironment. However, whether ADSCs have a hand in ovarian cancer progression remains unclear. In this study, we investigated the impact of human ADSCs derived from the omentum of normal donors on human epithelial ovarian cancer (EOC) cells in vitro and in vivo. Direct and indirect co-culture models including ADSCs and human EOC cell lines were established and the effects of ADSCs on EOC cell proliferation were evaluated by EdU incorporation and flow cytometry. Transwell migration assays and detection of MMPs were performed to assess the invasion activity of EOC cells in vitro. Mouse models were established by intraperitoneal injection of EOC cells with or without concomitant ADSCs to investigate the role of ADSCs in tumor progression in vivo. We found that ADSCs significantly promoted proliferation and invasion of EOC cells in both direct and indirect co-culture assays. In addition, after co-culture with ADSCs, EOC cells secreted higher levels of matrix metalloproteinases (MMPs), and inhibition of MMP2 and MMP9 partially relieved the tumor-promoting effects of ADSCs in vitro. In mouse xenograft models, we confirmed that ADSCs promoted EOC growth and metastasis and elevated the expression of MMP2 and MMP9. Our findings indicate that omental ADSCs play a promotive role during ovarian cancer progression. - Highlights: • Omental adipose derived stem cells enhanced growth and invasion properties of ovarian cancer cells. • Adipose derived stem cells promoted the growth and metastasis of ovarian cancer in mice models. • Adipose derived stem cells promoted MMPs expression and secretion of ovarian cancer cells. • Elevated MMPs mediated the tumor promoting effects of ADSCs.

  1. Adipose-derived mesenchymal stem cells promote cell proliferation and invasion of epithelial ovarian cancer

    International Nuclear Information System (INIS)

    Chu, Yijing; Tang, Huijuan; Guo, Yan; Guo, Jing; Huang, Bangxing; Fang, Fang; Cai, Jing; Wang, Zehua

    2015-01-01

    Adipose-derived mesenchymal stem cell (ADSC) is an important component of tumor microenvironment. However, whether ADSCs have a hand in ovarian cancer progression remains unclear. In this study, we investigated the impact of human ADSCs derived from the omentum of normal donors on human epithelial ovarian cancer (EOC) cells in vitro and in vivo. Direct and indirect co-culture models including ADSCs and human EOC cell lines were established and the effects of ADSCs on EOC cell proliferation were evaluated by EdU incorporation and flow cytometry. Transwell migration assays and detection of MMPs were performed to assess the invasion activity of EOC cells in vitro. Mouse models were established by intraperitoneal injection of EOC cells with or without concomitant ADSCs to investigate the role of ADSCs in tumor progression in vivo. We found that ADSCs significantly promoted proliferation and invasion of EOC cells in both direct and indirect co-culture assays. In addition, after co-culture with ADSCs, EOC cells secreted higher levels of matrix metalloproteinases (MMPs), and inhibition of MMP2 and MMP9 partially relieved the tumor-promoting effects of ADSCs in vitro. In mouse xenograft models, we confirmed that ADSCs promoted EOC growth and metastasis and elevated the expression of MMP2 and MMP9. Our findings indicate that omental ADSCs play a promotive role during ovarian cancer progression. - Highlights: • Omental adipose derived stem cells enhanced growth and invasion properties of ovarian cancer cells. • Adipose derived stem cells promoted the growth and metastasis of ovarian cancer in mice models. • Adipose derived stem cells promoted MMPs expression and secretion of ovarian cancer cells. • Elevated MMPs mediated the tumor promoting effects of ADSCs

  2. Advances in cell proliferation and apoptosis signal pathway and therapies of polycystic kidney disease

    Directory of Open Access Journals (Sweden)

    Xiao-ying LIAN

    2016-12-01

    Full Text Available Polycystic kidney disease (PKD is one of the monogenic inherited diseases. In PKD, excessive cell proliferation and fluid secretion, and disruption of the mechanisms controlling tubular diameter may all lead to cyst formation. Current evidence has demonstrated that intracellular calcium ion and cAMP imbalance drive both abnormal cell proliferation and apoptosis signal pathway. The present paper summarized the evidence implicating calcium ion and cAMP as central players in the signaling pathway of cell proliferation and apoptosis in PKD, and considered the potential therapeutic approaches targeted to slow cyst growth in PKD. DOI: 10.11855/j.issn.0577-7402.2016.11.13

  3. Functioning of spontaneous and induced Con A regulators of T-cell proliferation. Modifying factors

    International Nuclear Information System (INIS)

    Kuz'mina, E.G.

    1989-01-01

    It is shown that active spontaneous non-specific regulators of T-cell proliferation are activated in peripheral blood ''in vivo'' by endogenous metabolites; non-specific regulator action can be induced ''in vitro'' by Con A, FGA. Non-specific regulators suppress and increase lymphocyte proliferation. Cyclic character of their functioning is revealed. 4 refs.; 1 tab

  4. Mechanisms for the proliferation of eosinophilic leukemia cells by FIP1L1-PDGFRα

    International Nuclear Information System (INIS)

    Ishihara, Kenji; Kitamura, Hajime; Hiraizumi, Kenji; Kaneko, Motoko; Takahashi, Aki; Zee, OkPyo; Seyama, Toshio; Hong, JangJa; Ohuchi, Kazuo; Hirasawa, Noriyasu

    2008-01-01

    The constitutively activated tyrosine kinase Fip1-like 1 (FIP1L1)-platelet-derived growth factor receptor α (PDGFRα) causes eosinophilic leukemia EoL-1 cells to proliferate. Recently, we demonstrated that histone deacetylase inhibitors suppressed this proliferation and induced the differentiation of EoL-1 cells into eosinophils in parallel with a decrease in the level of FIP1L1-PDGFRα. In this study, we analyzed the mechanism by which FIP1L1-PDGFRα induces the proliferation and whether the suppression of cell proliferation triggers the differentiation into eosinophils. The FIP1L1-PDGFRα inhibitor imatinib inhibited the proliferation of EoL-1 cells and decreased the level of the oncoprotein c-Myc as well as the phosphorylation of extracellular signal-regulated kinase and c-Jun N-terminal kinase (JNK). The proliferation of EoL-1 cells and expression of c-Myc were also inhibited by the MEK inhibitor U0126 and JNK inhibitor SP600125. The expression of the eosinophilic differentiation marker CCR3 was not induced by imatinib. These findings suggest that FIP1L1-PDGFRα induces the proliferation of EoL-1 cells through the induction of c-Myc expression via ERK and JNK signaling pathways, but is not involved in the inhibition of differentiation toward mature eosinophils

  5. Suppression of the cell proliferation in stomach cancer cells by the ZNRD1 gene

    International Nuclear Information System (INIS)

    Hong Liu; Zhang Yumei; Liu Na; Liu Changjiang; Zhi Min; Pan Yanglin; Lan Mei; Sun Li; Fan Daiming

    2004-01-01

    Zinc ribbon domain-containing 1 (ZNRD1), a transcription-associated gene, was recently found to be downregulated in human gastric cancer tissues as compared to the matched adjacent nonneoplastic tissues. In this study, we constructed the siRNA eukaryotic expression vectors of ZNRD1 and transfected them into normal gastric epithelial cells (GES-1). We also introduced the ZNRD1 gene into gastric cancer cells that do (SGC7901) and do not (AGS) express ZNRD1 endogenously. GES-1 cells stably transfected with the ZNRD1-RNAi were found to exhibit significantly quicker proliferation than empty vector transfectants. AGS cells stably transfected with the ZNRD1 cDNA exhibited significantly decreased growth rate as compared to control vector transfectants, whereas SGC7901 cells did not. Furthermore, ZNRD1 suppresses growth of AGS cells in soft agar and tumor formation in athymic nude mice. This study clearly demonstrates that ZNRD1 may play an important role in the control of human gastric cancer development by regulating cell proliferation. These results provide new insights into the function of ZNRD1 and further validate ZNRD1 as a potential therapeutic target in gastric cancer

  6. Chronic hypoxia promotes pulmonary artery endothelial cell proliferation through H2O2-induced 5-lipoxygenase.

    Directory of Open Access Journals (Sweden)

    Kristi M Porter

    Full Text Available Pulmonary Hypertension (PH is a progressive disorder characterized by endothelial dysfunction and proliferation. Hypoxia induces PH by increasing vascular remodeling. A potential mediator in hypoxia-induced PH development is arachidonate 5-Lipoxygenase (ALOX5. While ALOX5 metabolites have been shown to promote pulmonary vasoconstriction and endothelial cell proliferation, the contribution of ALOX5 to hypoxia-induced proliferation remains unknown. We hypothesize that hypoxia exposure stimulates HPAEC proliferation by increasing ALOX5 expression and activity. To test this, human pulmonary artery endothelial cells (HPAEC were cultured under normoxic (21% O2 or hypoxic (1% O2 conditions for 24-, 48-, or 72 hours. In a subset of cells, the ALOX5 inhibitor, zileuton, or the 5-lipoxygenase activating protein inhibitor, MK-886, was administered during hypoxia exposure. ALOX5 expression was measured by qRT-PCR and western blot and HPAEC proliferation was assessed. Our results demonstrate that 24 and 48 hours of hypoxia exposure have no effect on HPAEC proliferation or ALOX5 expression. Seventy two hours of hypoxia significantly increases HPAEC ALOX5 expression, hydrogen peroxide (H2O2 release, and HPAEC proliferation. We also demonstrate that targeted ALOX5 gene silencing or inhibition of the ALOX5 pathway by pharmacological blockade attenuates hypoxia-induced HPAEC proliferation. Furthermore, our findings indicate that hypoxia-induced increases in cell proliferation and ALOX5 expression are dependent on H2O2 production, as administration of the antioxidant PEG-catalase blocks these effects and addition of H2O2 to HPAEC promotes proliferation. Overall, these studies indicate that hypoxia exposure induces HPAEC proliferation by activating the ALOX5 pathway via the generation of H2O2.