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Sample records for apoptosis senescence proliferation

  1. Multiple effects of TRAIL in human carcinoma cells: Induction of apoptosis, senescence, proliferation, and cytokine production

    International Nuclear Information System (INIS)

    Levina, Vera; Marrangoni, Adele M.; DeMarco, Richard; Gorelik, Elieser; Lokshin, Anna E.

    2008-01-01

    TRAIL is a death ligand that induces apoptosis in malignant but not normal cells. Recently the ability of TRAIL to induce proliferation in apoptosis-resistant normal and malignant cells was reported. In this study, we analyzed TRAIL effects in apoptosis sensitive MCF7, OVCAR3 and H460 human tumor cell lines. TRAIL at low concentrations preferentially induced cell proliferation. At 100 ng/ml, apoptotic death was readily observed, however surviving cells acquired higher proliferative capacity. TRAIL-stimulated production of several cytokines, IL-8, RANTES, MCP-1 and bFGF, and activation of caspases 1 and 8 was essential for this effect. Antibodies to IL-8, RANTES, and bFGF blocked TRAIL-induced cell proliferation and further stimulated apoptosis. For the first time, we report that high TRAIL concentrations induced cell senescence as determined by the altered morphology and expression of several senescence markers: SA-β-gal, p21 Waf1/Cip1 , p16 INK4a , and HMGA. Caspase 9 inhibition protected TRAIL-treated cells from senescence, whereas inhibition of caspases 1 and 8 increased the yield of SLP cells. In conclusion, in cultured human carcinoma cells, TRAIL therapy results in three functional outcomes, apoptosis, proliferation and senescence. TRAIL-induced proapoptotic and prosurvival responses correlate with the strength of signaling. TRAIL-induced cytokine production is responsible for its proliferative and prosurvival effects

  2. Clinical significance of proliferation, apoptosis and senescence of nasopharyngeal cells by the simultaneously blocking EGF, IGF-1 receptors and Bcl-xl genes

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    Dai, Guodong; Peng, Tao; Zhou, Xuhong; Zhu, Jun; Kong, Zhihua; Ma, Li; Xiong, Zhi; Yuan, Yulin

    2013-01-01

    Highlight: •Construction of shRNA segments expression vectors is valid by the investigation of RT-PCR for IGF1R, EGFR and Bcl-xl mRNA and protein expression. •Studies have suggested that the vectors in blocking these genes of the growth factor receptors and anti- apoptosis is capable of breaking the balance of tumor growth so that tumor trend apoptosis and senescence. •Simultaneously blocking multiple genes that are abnormally expressed may be more effective in treating cancer cells than silencing a single gene. -- Abstract: Background: In previous work, we constructed short hairpin RNA (shRNA) expression plasmids that targeted human EGF and IGF-1 receptors messenger RNA, respectively, and demonstrated that these vectors could induce apoptosis of human nasopharyngeal cell lines (CNE2) and inhibit ligand-induced pAkt and pErk activation. Method: We have constructed multiple shRNA expression vectors of targeting EGFR, IGF1R and Bcl-xl, which were transfected to the CNE2 cells. The mRNA expression was assessed by RT-PCR. The growth of the cells, cell cycle progression, apoptosis of the cells, senescent tumor cells and the proteins of EGFR, IGF1R and Bcl-xl were analyzed by MTT, flow cytometry, cytochemical therapy or Western blot. Results: In group of simultaneously blocking EGFR, IGF1R and Bcl-xl genes, the mRNA of EGFR, IGF1R and Bcl-xl expression was decreased by (66.66 ± 3.42)%, (73.97 ± 2.83)% and (64.79 ± 2.83)%, and the protein expressions was diminished to (67.69 ± 4.02)%, (74.32 ± 2.30)%, and (60.00 ± 3.34)%, respectively. Meanwhile, the cell apoptosis increased by 65.32 ± 0.18%, 65.16 ± 0.25% and 55.47 ± 0.45%, and senescent cells increased by 1.42 ± 0.15%, 2.26 ± 0.15% and 3.22 ± 0.15% in the second, third and fourth day cultures, respectively. Conclusions: Simultaneously blocking EGFR, IGF1R and Bcl-xl genes is capable of altering the balance between proliferating versus apoptotic and senescent cells in the favor of both of apoptosis and

  3. Clinical significance of proliferation, apoptosis and senescence of nasopharyngeal cells by the simultaneously blocking EGF, IGF-1 receptors and Bcl-xl genes

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    Dai, Guodong [Anatomy and Embryology, Wuhan University School of Medicine, Wuhan, Hubei 430071 (China); Peng, Tao; Zhou, Xuhong [Department of Otolaryngology-Head and Neck Surgery, Zhongnan Hospital of Wuhan University, Wuhan 430071 (China); Zhu, Jun; Kong, Zhihua; Ma, Li; Xiong, Zhi [Anatomy and Embryology, Wuhan University School of Medicine, Wuhan, Hubei 430071 (China); Yuan, Yulin, E-mail: yuanyulin19620120@126.com [Anatomy and Embryology, Wuhan University School of Medicine, Wuhan, Hubei 430071 (China)

    2013-11-01

    Highlight: •Construction of shRNA segments expression vectors is valid by the investigation of RT-PCR for IGF1R, EGFR and Bcl-xl mRNA and protein expression. •Studies have suggested that the vectors in blocking these genes of the growth factor receptors and anti- apoptosis is capable of breaking the balance of tumor growth so that tumor trend apoptosis and senescence. •Simultaneously blocking multiple genes that are abnormally expressed may be more effective in treating cancer cells than silencing a single gene. -- Abstract: Background: In previous work, we constructed short hairpin RNA (shRNA) expression plasmids that targeted human EGF and IGF-1 receptors messenger RNA, respectively, and demonstrated that these vectors could induce apoptosis of human nasopharyngeal cell lines (CNE2) and inhibit ligand-induced pAkt and pErk activation. Method: We have constructed multiple shRNA expression vectors of targeting EGFR, IGF1R and Bcl-xl, which were transfected to the CNE2 cells. The mRNA expression was assessed by RT-PCR. The growth of the cells, cell cycle progression, apoptosis of the cells, senescent tumor cells and the proteins of EGFR, IGF1R and Bcl-xl were analyzed by MTT, flow cytometry, cytochemical therapy or Western blot. Results: In group of simultaneously blocking EGFR, IGF1R and Bcl-xl genes, the mRNA of EGFR, IGF1R and Bcl-xl expression was decreased by (66.66 ± 3.42)%, (73.97 ± 2.83)% and (64.79 ± 2.83)%, and the protein expressions was diminished to (67.69 ± 4.02)%, (74.32 ± 2.30)%, and (60.00 ± 3.34)%, respectively. Meanwhile, the cell apoptosis increased by 65.32 ± 0.18%, 65.16 ± 0.25% and 55.47 ± 0.45%, and senescent cells increased by 1.42 ± 0.15%, 2.26 ± 0.15% and 3.22 ± 0.15% in the second, third and fourth day cultures, respectively. Conclusions: Simultaneously blocking EGFR, IGF1R and Bcl-xl genes is capable of altering the balance between proliferating versus apoptotic and senescent cells in the favor of both of apoptosis and

  4. Acute dyskerin depletion triggers cellular senescence and renders osteosarcoma cells resistant to genotoxic stress-induced apoptosis

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    Lin, Ping; Mobasher, Maral E.; Alawi, Faizan

    2014-01-01

    Highlights: • Dyskerin depletion triggers cellular senescence in U2OS osteosarcoma cells. • Dyskerin-depleted cells are resistant to apoptosis induced by genotoxic stress. • Chromatin relaxation sensitizes dyskerin-depleted cells to apoptosis. - Abstract: Dyskerin is a conserved, nucleolar RNA-binding protein implicated in an increasing array of fundamental cellular processes. Germline mutation in the dyskerin gene (DKC1) is the cause of X-linked dyskeratosis congenita (DC). Conversely, wild-type dyskerin is overexpressed in sporadic cancers, and high-levels may be associated with poor prognosis. It was previously reported that acute loss of dyskerin function via siRNA-mediated depletion slowed the proliferation of transformed cell lines. However, the mechanisms remained unclear. Using human U2OS osteosarcoma cells, we show that siRNA-mediated dyskerin depletion induced cellular senescence as evidenced by proliferative arrest, senescence-associated heterochromatinization and a senescence-associated molecular profile. Senescence can render cells resistant to apoptosis. Conversely, chromatin relaxation can reverse the repressive effects of senescence-associated heterochromatinization on apoptosis. To this end, genotoxic stress-induced apoptosis was suppressed in dyskerin-depleted cells. In contrast, agents that induce chromatin relaxation, including histone deacetylase inhibitors and the DNA intercalator chloroquine, sensitized dyskerin-depleted cells to apoptosis. Dyskerin is a core component of the telomerase complex and plays an important role in telomere homeostasis. Defective telomere maintenance resulting in premature senescence is thought to primarily underlie the pathogenesis of X-linked DC. Since U2OS cells are telomerase-negative, this leads us to conclude that loss of dyskerin function can also induce cellular senescence via mechanisms independent of telomere shortening

  5. Interleukin-6 promotes the migration and cellular senescence and inhibits apoptosis of human intrahepatic biliary epithelial cells.

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    Li, Ran; Dong, Juan; Bu, Xiu-Qin; Huang, Yong; Yang, Jing-Yu; Dong, Xuan; Liu, Jie

    2018-02-01

    Biliary epithelial cells (BEC) are closely related to some immune regulatory bile duct diseases. However, the complexity and polymorphism of the morphology and function of bile duct cells have hindered further investigation. Therefore, the aim of this study is to investigate how interleukin-6 (IL-6) affects the migration, cellular senescence, and apoptosis of human intrahepatic biliary epithelial cells (HIBECs). The HIBECs were stimulated by different concentrations of IL-6 (0, 5, 10, 15, and 20 ng/mL, respectively). Transwell assay was performed in order to measure the migration abilities, positive β-Galactosidase staining for the cellular senescence of HIBECs, MTT assay for changes of proliferation after IL-6 treatment and flow cytometry for cell cycle and apoptosis. The reverse transcription quantitative polymerase chain reaction (RT-qPCR) and Western blotting were conducted in order to detect the mRNA and protein expressions of epithelial-mesenchymal transition (EMT) markers in HIBECs. In comparison to the 0 ng/mL group, in the 5, 10, 15, and 20 ng/mL groups, a significant increase in the number of migratory HIBECs, proliferation, along with mRNA and protein expressions of EMT markers was observed. While the mRNA and protein expressions of epithelial markers, the number of β-galactosidase positive staining cells, as well as apoptosis rate of HIBECs dramatic decreased. Further, the aforementioned changes were significantly more evident in the 15 and 20 ng/mL groups in comparison to the 5 and 10 ng/mL groups. IL-6 may stimulate EMT, enhance the migration and proliferation, and inhibit apoptosis of HIBECs, thus delaying cellular senescence. © 2017 Wiley Periodicals, Inc.

  6. Activation of Adenosine Receptor A2A Increases HSC Proliferation and Inhibits Death and Senescence by Down-regulation of p53 and Rb

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    Md. Kaimul eAhsan

    2014-04-01

    Full Text Available Background & Aims: During fibrosis hepatic stellate cells (HSC undergo activation, proliferation and senescence but the regulation of these important processes is poorly understood. The adenosine A2A receptor (A2A is known to be present on HSC, and its activation results in liver fibrosis. In this study, we tested if A2A has a role in the regulation of HSC proliferation, apoptosis, senescence, and the relevant molecular mechanism.Methods: The ability of adenosine to regulate p53 and Rb protein levels, proliferation, apoptosis and senescence was tested in the human HSC cell line LX-2 and rat primary HSC.Results: Adenosine receptor activation down-regulates p53 and Rb protein levels, increases BrdU incorporation and increases cell survival in LX-2 cells and in primary rat HSC. These effects of NECA were reproduced by an adenosine A2A receptor specific agonist (CGS21680 and blocked by a specific antagonist (ZM241385. By day twenty-one of culture primary rat HSC entered senescence and expressed -gal which was significantly inhibited by NECA. Furthermore, NECA induced down regulation of p53 and Rb and Rac1, and decreased phosphorylation of p44-42 MAP Kinase in LX-2 cells and primary rat HSC. These effects were reproduced by the cAMP analog 8-Bromo-cAMP, and the adenylyl cyclase activator forskolin, and were blocked by PKA inhibitors.Conclusions: These results demonstrate that A2A receptor regulates a number of HSC fate decisions and induces greater HSC proliferation, reduces apoptosis and senescence by decreasing p53 and Rb through cAMP-PKA/Rac1/p38 MAPK pathway. This provides a mechanism for adenosine induced HSC regulation and liver fibrosis.

  7. Ribosomal L1 domain and lysine-rich region are essential for CSIG/ RSL1D1 to regulate proliferation and senescence

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    Ma, Liwei; Zhao, Wenting; Zheng, Quanhui; Chen, Tianda; Qi, Ji; Li, Guodong; Tong, Tanjun, E-mail: tztong@bjmu.edu.cn

    2016-01-15

    The expression change of cellular senescence-associated genes is underlying the genetic foundation of cellular senescence. Using a suppressive subtractive hybridization system, we identified CSIG (cellular senescence-inhibited gene protein; RSL1D1) as a novel senescence-associated gene. CSIG is implicated in various process including cell cycle regulation, apoptosis, and tumor metastasis. We previously showed that CSIG plays an important role in regulating cell proliferation and cellular senescence progression through inhibiting PTEN, however, which domain or region of CSIG contributes to this function? To clarify this question, we investigated the functional importance of ribosomal L1 domain and lysine (Lys) -rich region of CSIG. The data showed that expression of CSIG potently reduced PTEN expression, increased cell proliferation rates, and reduced the senescent phenotype (lower SA-β-gal activity). By contrast, neither the expression of CSIG N- terminal (NT) fragment containing the ribosomal L1 domain nor C-terminal (CT) fragment containing Lys-rich region could significantly altered the levels of PTEN; instead of promoting cell proliferation and delaying cellular senescence, expression of CSIG-NT or CSIG-CT inhibited cell proliferation and accelerated cell senescence (increased SA-β-gal activity) compared to either CSIG over-expressing or control (empty vector transfected) cells. The further immunofluorescence analysis showed that CSIG-CT and CSIG-NT truncated proteins exhibited different subcellular distribution with that of wild-type CSIG. Conclusively, both ribosomal L1 domain and Lys-rich region of CSIG are critical for CSIG to act as a regulator of cell proliferation and cellular senescence. - Highlights: • The ribosomal L1 domain and lysine-rich region of CSIG were expressed. • They are critical for CSIG to regulate proliferation and senescence. • CSIG and its domains exhibit different subcellular distribution.

  8. Ribosomal L1 domain and lysine-rich region are essential for CSIG/ RSL1D1 to regulate proliferation and senescence

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    Ma, Liwei; Zhao, Wenting; Zheng, Quanhui; Chen, Tianda; Qi, Ji; Li, Guodong; Tong, Tanjun

    2016-01-01

    The expression change of cellular senescence-associated genes is underlying the genetic foundation of cellular senescence. Using a suppressive subtractive hybridization system, we identified CSIG (cellular senescence-inhibited gene protein; RSL1D1) as a novel senescence-associated gene. CSIG is implicated in various process including cell cycle regulation, apoptosis, and tumor metastasis. We previously showed that CSIG plays an important role in regulating cell proliferation and cellular senescence progression through inhibiting PTEN, however, which domain or region of CSIG contributes to this function? To clarify this question, we investigated the functional importance of ribosomal L1 domain and lysine (Lys) -rich region of CSIG. The data showed that expression of CSIG potently reduced PTEN expression, increased cell proliferation rates, and reduced the senescent phenotype (lower SA-β-gal activity). By contrast, neither the expression of CSIG N- terminal (NT) fragment containing the ribosomal L1 domain nor C-terminal (CT) fragment containing Lys-rich region could significantly altered the levels of PTEN; instead of promoting cell proliferation and delaying cellular senescence, expression of CSIG-NT or CSIG-CT inhibited cell proliferation and accelerated cell senescence (increased SA-β-gal activity) compared to either CSIG over-expressing or control (empty vector transfected) cells. The further immunofluorescence analysis showed that CSIG-CT and CSIG-NT truncated proteins exhibited different subcellular distribution with that of wild-type CSIG. Conclusively, both ribosomal L1 domain and Lys-rich region of CSIG are critical for CSIG to act as a regulator of cell proliferation and cellular senescence. - Highlights: • The ribosomal L1 domain and lysine-rich region of CSIG were expressed. • They are critical for CSIG to regulate proliferation and senescence. • CSIG and its domains exhibit different subcellular distribution.

  9. Activation of a PGC-1-related Coactivator (PRC)-dependent Inflammatory Stress Program Linked to Apoptosis and Premature Senescence*

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    Gleyzer, Natalie; Scarpulla, Richard C.

    2013-01-01

    PGC-1-related coactivator (PRC), a growth-regulated member of the PGC-1 coactivator family, contributes to the expression of the mitochondrial respiratory apparatus. PRC also orchestrates a robust response to metabolic stress by promoting the expression of multiple genes specifying inflammation, proliferation, and metabolic reprogramming. Here, we demonstrate that this PRC-dependent stress program is activated during apoptosis and senescence, two major protective mechanisms against cellular dysfunction. Both PRC and its targets (IL1α, SPRR2D, and SPRR2F) were rapidly induced by menadione, an agent that promotes apoptosis through the generation of intracellular oxidants. Menadione-induced apoptosis and the PRC stress program were blocked by the antioxidant N-acetylcysteine. The PRC stress response was also activated by the topoisomerase I inhibitor 7-ethyl-10-hydroxycamptothecin (SN-38), an inducer of premature senescence in tumor cells. Cells treated with SN-38 displayed morphological characteristics of senescence and express senescence-associated β-galactosidase activity. In contrast to menadione, the SN-38 induction of the PRC program occurred over an extended time course and was antioxidant-insensitive. The potential adaptive function of the PRC stress response was investigated by treating cells with meclizine, a drug that promotes glycolytic energy metabolism and has been linked to cardio- and neuroprotection against ischemia-reperfusion injury. Meclizine increased lactate production and was a potent inducer of the PRC stress program, suggesting that PRC may contribute to the protective effects of meclizine. Finally, c-MYC and PRC were coordinately induced under all conditions tested, implicating c-MYC in the biological response to metabolic stress. The results suggest a general role for PRC in the adaptive response to cellular dysfunction. PMID:23364789

  10. Sun Ginseng Protects Endothelial Progenitor Cells From Senescence Associated Apoptosis

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    Im, Wooseok; Chung, Jin-Young; Bhan, Jaejun; Lim, Jiyeon; Lee, Soon-Tae; Chu, Kon; Kim, Manho

    2012-01-01

    Endothelial progenitor cells (EPC) are a population of cells that circulate in the blood stream. They play a role in angiogenesis and, therefore, can be prognostic markers of vascular repair. Ginsenoside Rg3 prevents endothelial cell apoptosis through the inhibition of the mitochondrial caspase pathway. It also affects estrogen activity, which reduces EPC senescence. Sun ginseng (SG), which is heat-processed ginseng, has a high content of ginsenosides. The purpose of this study was to investigate the protective effects of SG on senescence-associated apoptosis in EPCs. In order to isolate EPCs, mononuclear cells of human blood buffy coats were cultured and characterized by their uptake of acetylated low-density lipoprotein (acLDL) and their binding of Ulex europaeus agglutinin I (ulex-lectin). Flow cytometry with annexin-V staining was performed in order to assess early and late apoptosis. Senescence was determined by β-galactosidase (β-gal) staining. Staining with 4′-6-Diamidino-2-phenylindole verified that most adherent cells (93±2.7%) were acLDL-positive and ulex-lectin-positive. The percentage of β-gal-positive EPCs was decreased from 93.8±2.0% to 62.5±3.6% by SG treatment. A fluorescence-activated cell sorter (FACS) analysis showed that 4.9% of EPCs were late apoptotic in controls. Sun ginseng decreased the apoptotic cell population by 39% in the late stage of apoptosis from control baseline levels. In conclusion, these results show antisenescent and antiapoptotic effects of SG in human-derived EPCs, indicating that SG can enhance EPC-mediated repair mechanisms. PMID:23717107

  11. Targeted Apoptosis of Senescent Cells Restores Tissue Homeostasis in Response to Chemotoxicity and Aging.

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    Baar, Marjolein P; Brandt, Renata M C; Putavet, Diana A; Klein, Julian D D; Derks, Kasper W J; Bourgeois, Benjamin R M; Stryeck, Sarah; Rijksen, Yvonne; van Willigenburg, Hester; Feijtel, Danny A; van der Pluijm, Ingrid; Essers, Jeroen; van Cappellen, Wiggert A; van IJcken, Wilfred F; Houtsmuller, Adriaan B; Pothof, Joris; de Bruin, Ron W F; Madl, Tobias; Hoeijmakers, Jan H J; Campisi, Judith; de Keizer, Peter L J

    2017-03-23

    The accumulation of irreparable cellular damage restricts healthspan after acute stress or natural aging. Senescent cells are thought to impair tissue function, and their genetic clearance can delay features of aging. Identifying how senescent cells avoid apoptosis allows for the prospective design of anti-senescence compounds to address whether homeostasis can also be restored. Here, we identify FOXO4 as a pivot in senescent cell viability. We designed a FOXO4 peptide that perturbs the FOXO4 interaction with p53. In senescent cells, this selectively causes p53 nuclear exclusion and cell-intrinsic apoptosis. Under conditions where it was well tolerated in vivo, this FOXO4 peptide neutralized doxorubicin-induced chemotoxicity. Moreover, it restored fitness, fur density, and renal function in both fast aging Xpd TTD/TTD and naturally aged mice. Thus, therapeutic targeting of senescent cells is feasible under conditions where loss of health has already occurred, and in doing so tissue homeostasis can effectively be restored. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. The oncogenic fusion protein RUNX1-CBFA2T1 supports proliferation and inhibits senescence in t(8;21)-positive leukaemic cells

    International Nuclear Information System (INIS)

    Martinez, Natalia; Heidenreich, Olaf; Drescher, Bettina; Riehle, Heidemarie; Cullmann, Claire; Vornlocher, Hans-Peter; Ganser, Arnold; Heil, Gerhard; Nordheim, Alfred; Krauter, Jürgen

    2004-01-01

    The fusion protein RUNX1-CBFA2T1 associated with t(8;21)-positive acute myeloid leukaemia is a potent inhibitor of haematopoetic differentiation. The role of RUNX1-CBFA2T1 in leukaemic cell proliferation is less clear. We examined the consequences of siRNA-mediated RUNX1-CBFA2T1 depletion regarding proliferation and clonogenicity of t(8;21)-positive cell lines. The t(8;21)-positive cell line Kasumi-1 was electroporated with RUNX1-CBFA2T1 or control siRNAs followed by analysis of proliferation, colony formation, cell cycle distribution, apoptosis and senescence. Electroporation of Kasumi-1 cells with RUNX1-CBFA2T1 siRNAs, but not with control siRNAs, resulted in RUNX1-CBFA2T1 suppression which lasted for at least 5 days. A single electroporation with RUNX1-CBFA2T1 siRNA severely diminished the clonogenicity of Kasumi-1 cells. Prolonged RUNX1-CBFA2T1 depletion inhibited proliferation in suspension culture and G1-S transition during the cell cycle, diminished the number of apoptotic cells, but induced cellular senescence. The addition of haematopoetic growth factors could not rescue RUNX1-CBFA2T1-depleted cells from senescence, and could only partially restore their clonogenicity. RUNX1-CBFA2T1 supports the proliferation and expansion of t(8;21)-positive leukaemic cells by preventing cellular senescence. These findings suggest a central role of RUNX1-CBFA2T1 in the maintenance of the leukaemia. Therefore, RUNX1-CBFA2T1 is a promising and leukaemia-specific target for molecularly defined therapeutic approaches

  13. Tyr phosphatase-mediated P-ERK inhibition suppresses senescence in EIA + v-raf transformed cells, which, paradoxically, are apoptosis-protected in a MEK-dependent manner.

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    De Vitis, Stefania; Sonia Treglia, Antonella; Ulianich, Luca; Turco, Stefano; Terrazzano, Giuseppe; Lombardi, Angela; Miele, Claudia; Garbi, Corrado; Beguinot, Francesco; Di Jeso, Bruno

    2011-02-01

    Activation of the Ras-Raf-extracellular signal-regulated kinase (ERK) pathway causes not only proliferation and suppression of apoptosis but also the antioncogenic response of senescence. How these contrasting effects are reconciled to achieve cell transformation and cancer formation is poorly understood. In a system of two-step carcinogenesis (dedifferentiated PC EIA, transformed PC EIA-polyoma-middle T [PC EIA + Py] and PC EIA-v-raf [PC EIA + raf] cells], v-raf cooperated with EIA by virtue of a strong prosurvival effect, not elicited by Py-middle T, evident toward serum-deprivation-and H(2)O(2)-induced apoptosis. Apoptosis was detected by DNA fragmentation and annexin V staining. The prosurvival function of v-raf was, in part, mitogen-activated protein kinase/ERK kinase (MEK)-dependent, as shown by pharmacological MEK inhibition. The MEK-dependent antiapoptotic effect of v-raf was exerted despite a lower level of P-ERK1/2 in EIA + raf cells with respect to EIA + Py/EIA cells, which was dependent on a high tyrosine phosphatase activity, as shown by orthovanadate blockade. An ERK1/2 tyrosine phosphatase was likely involved. The high tyrosine phosphatase activity was instrumental to the complete suppression of senescence, detected by β-galactosidase activity, because tyrosine phosphatase blockade induced senescence in EIA + raf but not in EIA + Py cells. High tyrosine phosphatase activity and evasion from senescence were confirmed in an anaplastic thyroid cancer cell line. Therefore, besides EIA, EIA + raf cells suppress senescence through a new mechanism, namely, phosphatase-mediated P-ERK1/2 inhibition, but, paradoxically, retain the oncogenic effects of the Raf-ERK pathway. We propose that the survival effect of Raf is not a function of absolute P-ERK1/2 levels at a given time but is rather dynamically dependent on greater variations after an apoptotic stimulus.

  14. Tyr Phosphatase-Mediated P-ERK Inhibition Suppresses Senescence in EIA + v-raf Transformed Cells, Which, Paradoxically, Are Apoptosis-Protected in a MEK-Dependent Manner

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    Stefania De Vitis

    2011-02-01

    Full Text Available Activation of the Ras-Raf-extracellular signal-regulated kinase (ERK pathway causes not only proliferation and suppression of apoptosis but also the antioncogenic response of senescence. How these contrasting effects are reconciled to achieve cell transformation and cancer formation is poorly understood. In a system of two-step carcinogenesis (dedifferentiated PC EIA, transformed PC EIA-polyoma-middle T [PC EIA + Py] and PC EIA-v-raf [PC EIA + raf] cells], v-raf cooperated with EIA by virtue of a strong prosurvival effect, not elicited by Py-middle T, evident toward serum-deprivation-and H2O2-induced apoptosis. Apoptosis was detected by DNA fragmentation and annexin V staining. The prosurvival function of v-raf was, in part, mitogen-activated protein kinase/ERK kinase (MEK-dependent, as shown by pharmacological MEK inhibition. The MEK-dependent antiapoptotic effect of v-raf was exerted despite a lower level of P-ERK1/2 in EIA + raf cells with respect to EIA + Py/EIA cells, which was dependent on a high tyrosine phosphatase activity, as shown by orthovanadate blockade. An ERK1/2 tyrosine phosphatase was likely involved. The high tyrosine phosphatase activity was instrumental to the complete suppression of senescence, detected by β-galactosidase activity, because tyrosine phosphatase blockade induced senescence in EIA + raf but not in EIA + Py cells. High tyrosine phosphatase activity and evasion from senescence were confirmed in an anaplastic thyroid cancer cell line. Therefore, besides EIA, EIA + raf cells suppress senescence through a new mechanism, namely, phosphatase-mediated P-ERK1/2 inhibition, but, paradoxically, retain the oncogenic effects of the Raf-ERK pathway. We propose that the survival effect of Raf is not a function of absolute P-ERK1/2 levels at a given time but is rather dynamically dependent on greater variations after an apoptotic stimulus.

  15. Cellular Senescence in Postmitotic Cells: Beyond Growth Arrest.

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    Sapieha, Przemyslaw; Mallette, Frédérick A

    2018-04-25

    In mitotic cells, cellular senescence is a permanent state of G1 arrest, that may have evolved in parallel to apoptosis, to limit proliferation of damaged cells and oncogenesis. Recent studies have suggested that postmitotic cells are also capable of entering a state of senescence, although the repercussions of postmitotic cellular senescence (PoMiCS) on tissue health and function are currently ill-defined. In tissues made largely of post-mitotic cells, it is evolutionary advantageous to preserve cellular integrity and cellular senescence of post-mitotic cells may prevent stressor-induced tissue degeneration and promote tissue repair. Paradoxically, PoMiCS may also contribute to disease progression through the generation of inflammatory mediators, termed the senescence-associated secretory phenotype. Here, we discuss the potential roles of PoMiCS and propose to enlarge the current definition of cellular senescence to postmitotic terminally differentiated cells. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. Effects of PKM2 Gene Silencing on the Proliferation and Apoptosis of Colorectal Cancer LS-147T and SW620 Cells

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    Ran Ao

    2017-07-01

    Full Text Available Background/Aims: This paper aims to explore the effects of pyruvate kinase (PK M2 gene silencing on the proliferation and apoptosis of colorectal cancer (CRC LS-147T and SW620 cells. Methods: CRC LS-147T and SW620 cells highly expressing PKM2 were randomly selected by quantitative real-time polymerase chain reaction (qRT-PCR and then assigned into the blank (no transfection, PKM2-shRNA (transfection with shRNA and empty plasmid (transfection with empty plasmid groups. Immunofluorescence was applied to detect PKM2 protein expression. qRT-PCR and Western blotting were conducted to assess mRNA and protein expression of PKM2, p53 and p21. The cell counting kit-8 (CCK-8 assay was used to assess cell proliferation. Flow cytometry was used to assess the cell cycle and apoptosis rate, and a senescence-associated β-galactosidase staining kit was used to assess cell senescence. Results: PKM2 exhibited high mRNA expression among CRC LS-147T and SW620 cells with remarkable protein expression noted in the cytoplasm and nucleus. The PKM2-shRNA group exhibited reduced PKM2 mRNA and protein expression, whereas p53 and p21 expression was increased compared with the blank and empty plasmid groups. Cell proliferation in PKM2-shRNA cells decreased significantly compared with the blank group and empty plasmid groups. The PKM2-shRNA group exhibited more cells in the G1 phase and fewer cells in the G2/M phase compared with the blank and empty plasmid groups. In addition, the PKM2-shRNA group exhibited significantly increased apoptosis rates and β-galactosidase activity compared with the blank and empty plasmid groups. Conclusion: Our study demonstrates that PKM2 gene silencing suppresses proliferation and promotes apoptosis in LS-147T and SW620 cells.

  17. The Lcn2-engineered HEK-293 cells show senescence under stressful condition

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    Bahareh Bahmani

    2015-05-01

    Full Text Available Objective(s: Lipocalin2 (Lcn2 gene is highly expressed in response to various types of cellular stresses. The precise role of Lcn2 has not been fully understood yet. However, it plays a key role in controlling vital cellular processes such as proliferation, apoptosis and metabolism. Recently it was shown that Lcn2 decreases senescence and increases proliferation of mesenchymal stem cells (MSC with finite life span under either normal or oxidative stress conditions. However, Lcn2 effects on immortal cell line with infinite proliferation are not defined completely.  Materials and Material and Methods: HEK-293 cells were transfected with recombinant pcDNA3.1 containing Lcn2 fragment (pcDNA3.1-Lcn2. Expression of lipocalin2 in transfected cells was evaluated by RT-PCR, real time RT-PCR, and ELISA. Different cell groups were treated with H2O2 and WST-1 assay was performed to determine their proliferation rate. Senescence was studied by β-galactosidase and gimsa staining methods as well as evaluation of the expression of senescence-related genes by real time RT-PCR. Results: Lcn2 increased cell proliferation under normal culture condition, while the proliferation slightly decreased under oxidative stress.  This decrease was further found to be attributed to senescence. Conclusion: Our findings indicated that under harmful conditions, Lcn2 gene is responsible for the regulation of cell survival through senescence.

  18. Pentoxifylline sensitizes human cervical tumor cells to cisplatin-induced apoptosis by suppressing NF-kappa B and decreased cell senescence

    International Nuclear Information System (INIS)

    Hernandez-Flores, Georgina; Bravo-Cuellar, Alejandro; Ortiz-Lazareno, Pablo C; Lerma-Diaz, Jose Manuel; Dominguez-Rodriguez, Jorge R; Jave-Suarez, Luis F; Aguilar-Lemarroy, Adriana del C; Celis-Carrillo, Ruth de; Toro-Arreola, Susana del; Castellanos-Esparza, Yessica C

    2011-01-01

    Worldwide, cervical cancer is the second most common causes of cancer in women and represents an important mortality rate. Cisplatin (CIS) is a very important antitumoral agent and can lead tumor cells toward two important cellular states: apoptosis and senescence. In some types of cancers pentoxifylline (PTX) sensitizes these cells to the toxic action of chemotherapeutics drugs such as adriamycin, inducing apoptosis. In the present work, we studied in vitro whether PTX alone or in combination with CIS induces apoptosis and/or senescence in cervix cancer HeLa and SiHa cell lines infected with HPV types 16 and 18, respectively, as well as in immortalized keratinocytyes HaCaT cells. HeLa (HPV 18+), SiHa (HPV 16+) cervix cancer cells and non-tumorigenic immortalized HaCaT cells (control) were treated with PTX, CIS or both. The cellular toxicity and survival fraction of PTX and CIS were determinate by WST-1 and clonogenic assays respectively. Apoptosis, caspase activation and phosphorylation of ERK1/2, p38, p65 (NF-κB), Bcl-2 and Bcl-XL anti-apoptotic proteins were determinated by flow cytometry. Senescence by microscopy. Phosphorylation of IκBα and IκB total were measured by ELISA. Pro-apoptotic, anti-apoptotic and senescence genes, as well as HPV-E6/7 mRNA expression, were detected by RT-PCR. Our results show that after 24 hours of incubation PTX per se is toxic for cancer cells affecting cell viability and inducing apoptosis. The toxicity in HaCaT cells was minimal. CIS induces apoptosis in HeLa and SiHa cells and its effect was significantly increases when the cells were treated with PTX + CIS. In all studies there was a direct correlation with levels of caspases (-3, -6, -7, -9 and -8) activity and apoptosis. CIS induces important levels of senescence and phosphorylation of ERK1/2, p38, p65/RELA, and IκBα, and decreased the expression of anti-apoptotic protein Bcl-XL. Surprisingly these levels were significantly reduced by PTX in tumor cells, and at the same

  19. Senescent vs. non-senescent cells in the human annulus in vivo: Cell harvest with laser capture microdissection and gene expression studies with microarray analysis

    Directory of Open Access Journals (Sweden)

    Ingram Jane A

    2010-01-01

    associated with cell proliferation, extracellular matrix formation, cell signaling and other cell functions also showed significant modulation in senescent vs non-senescent cells. The aging/degenerating disc undergoes a well-recognized loss of cells; understanding senescent cells is important since their presence further reduces the disc's ability to generate new cells to replace those lost to necrosis or apoptosis.

  20. MDM2 inhibitor nutlin-3a induces apoptosis and senescence in cutaneous T-cell lymphoma: Role of p53

    DEFF Research Database (Denmark)

    Manfé, Valentina; Biskup, Edyta Urszula; Johansen, Peter

    2012-01-01

    cell lines, P53 mutation analysis identified a homozygous nonsense mutation (R196Stop in Hut-78) and a homozygous missense mutation (G245S in SeAx). In MyLa2000, Mac1, and Mac2a carrying wild-type P53, nutlin-3a induced apoptosis and senescence demonstrated by permanent G0/G1 cell-cycle block...... with intact p53 but also in Hut-78, SeAx, and Sézary cells. Thus, targeting p53 by nutlin-3a may constitute a therapeutic approach in CTCL because of increased apoptosis and senescence of tumor cells....

  1. Activation of p53 by nutlin-3a induces apoptosis and cellular senescence in human glioblastoma multiforme.

    Directory of Open Access Journals (Sweden)

    Ruth Villalonga-Planells

    2011-04-01

    Full Text Available Glioblastoma multiforme (GBM is the most common and aggressive primary brain tumor in adults. Despite concerted efforts to improve current therapies and develop novel clinical approaches, patient survival remains poor. As such, increasing attention has focused on developing new therapeutic strategies that specifically target the apoptotic pathway in order to improve treatment responses. Recently, nutlins, small-molecule antagonists of MDM2, have been developed to inhibit p53-MDM2 interaction and activate p53 signaling in cancer cells. Glioma cell lines and primary cultured glioblastoma cells were treated with nutlin-3a. Nutlin-3a induced p53-dependent G1- and G2-M cell cycle arrest and apoptosis in glioma cell lines with normal TP53 status. In addition, nutlin-arrested glioma cells show morphological features of senescence and persistent induction of p21 protein. Furthermore, senescence induced by nutlin-3a might be depending on mTOR pathway activity. In wild-type TP53 primary cultured cells, exposure to nutlin-3a resulted in variable degrees of apoptosis as well as cellular features of senescence. Nutlin-3a-induced apoptosis and senescence were firmly dependent on the presence of functional p53, as revealed by the fact that glioblastoma cells with knockdown p53 with specific siRNA, or cells with mutated or functionally impaired p53 pathway, were completely insensitive to the drug. Finally, we also found that nutlin-3a increased response of glioma cells to radiation therapy. The results provide a basis for the rational use of MDM2 antagonists as a novel treatment option for glioblastoma patients.

  2. Irradiation With Carbon Ion Beams Induces Apoptosis, Autophagy, and Cellular Senescence in a Human Glioma-Derived Cell Line

    International Nuclear Information System (INIS)

    Jinno-Oue, Atsushi; Shimizu, Nobuaki; Hamada, Nobuyuki; Wada, Seiichi; Tanaka, Atsushi; Shinagawa, Masahiko; Ohtsuki, Takahiro; Mori, Takahisa; Saha, Manujendra N.; Hoque, Ariful S.; Islam, Salequl; Kogure, Kimitaka; Funayama, Tomoo; Kobayashi, Yasuhiko

    2010-01-01

    Purpose: We examined biological responses of human glioma cells to irradiation with carbon ion beams (C-ions). Methods and Materials: A human glioma-derived cell line, NP-2, was irradiated with C-ions. Apoptotic cell nuclei were stained with Hoechst 33342. Induction of autophagy was examined either by staining cells with monodansylcadaverine (MDC) or by Western blotting to detect conversion of microtuble-associated protein light chain 3 (MAP-LC3) (LC3-I) to the membrane-bound form (LC3-II). Cellular senescence markers including induction of senescence-associated β-galactosidase (SA-β-gal) were examined. The mean telomere length of irradiated cells was determined by Southern blot hybridization. Expression of tumor suppressor p53 and cyclin/cyclin-dependent kinase inhibitor p21 WAF1/CIP1 in the irradiated cells was analyzed by Western blotting. Results: When NP-2 cells were irradiated with C-ions at 6 Gy, the major population of the cells died of apoptosis and autophagy. The residual fraction of attached cells ( WAF1/CIP1 was induced in NP-2 cells after irradiation. Furthermore, we found that irradiation with C-ions induced cellular senescence in a human glioma cell line lacking functional p53. Conclusions: Irradiation with C-ions induced apoptosis, autophagy, and cellular senescence in human glioma cells.

  3. [Effects of Astragali Radix combined with Angelicae Sinensis Radix on the proliferation of hematopoietic stem cells senescence model in mice].

    Science.gov (United States)

    Zhang, Ke-Sheng; Chen, Ling-Bo; Huang, Xiao-Ping; Deng, Chang-Qing

    2017-11-01

    The aim is to study the effect and its mechanism of Astragalus Radix combined with Angelicae Sinensis Radix on the proliferation of hematopoietic stem cells(HSCs) in senescence model. After drug-containing plasma of rats was prepared via intragastric administration, HSCs of mice were cultured in vitro, and then they were divided into blank control group, model group, blank plasma group, Astragalus Radix + Angelicae Sinensis Radix 1∶1 group and 10∶1 group, Angelicae Sinensis Radix plasma group, and Astragalus Radix plasma group. HSCs senescence model was induced by using tert-butyl hydrogen peroxide(t-BHP), and intervened by drug-containing plasma. Cells senescence rate was tested by SA-β-galactosidase staining method; cell cycle distribution was determined by flow cytometry; Cyclin D1, P21, and P53 mRNA were measured with RT-PCR, and Cyclin D1 protein expression was measured by Western blot. Results showed that after being induced by t-BHP, senescence rate of HSCs was increased; cell proliferation ability was decreased; count of G₀/G₁ phase cells was increased; count of G₂/M+S phase cells was reduced; Cyclin D1 expression was down-regulated while P53, P21 expression was up-regulated, which were reversed by Astragalus Radix + Angelicae Sinensis Radix 1∶1 and 10∶1, single Angelicae Sinensis Radix, and single Astragalus Radix plasma. Furthermore, the above effects were most obvious in Astragalus Radix+Angelicae Sinensis Radix 1∶1 group. These results suggested that t-BHP can promote HSCs senescence and reduce cell proliferation ability. Angelicae Sinensis Radix, Astragalus Radix and their combinations can inhibit HSCs senescence, promote HSCs proliferation as well as cell cycle conversion; moreover, the effects of 1∶1 Astragalus Radix+Angelicae Sinensis Radix were strongest. The mechanisms may be related to up-regulating the expression of cell cycle positive regulator, down-regulating the expression of cell cycle negative regulator, thus promoting

  4. MiR-495 Promotes Senescence of Mesenchymal Stem Cells by Targeting Bmi-1

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    Xiujun Li

    2017-06-01

    Full Text Available Background/Aims: Mesenchymal stem cells (MSCs play an important role in regulating angiogenesis and immune balance. Abnormal proliferation and function of MSCs were reported at maternal fetal interface in patients with pre-eclampsia (PE. Micro-RNA-495 was known to be upregulated in the MSCs derived from patients with PE. However, it is not clear whether the up-regulated miR-495 is related to the pathogenesis of PE. Methods: We analyzed the expression of miR-495 in MSCs and umbilical cords derived from healthy pregnancies (NC and PE, then we upregulated or downregulated the expression of miR-495 in MSCs derived from NC and tested the proliferation, apoptosis, migration, invasion, tube formation and senescence. Results: In the current study, we found that the expression of miR-495 was significantly increased in both umbilical cord tissues and MSCs in patients with severe PE. Overexpressing miR-495 arrested cell cycle in S phase and promoted cell apoptosis. The supernatants from miR-495-overexpressed-MSCs inhibited the migration of MSCs and HTR-8/SVneo, invasion of HTR-8/SVneo and tube formation of HUVEC, while si-miR-495 had the opposite effects. Furthermore, we analyzed the senescence related β-galactosidase activity and CD146 and found that miR-495 induced the senescence of MSCs. Molecular mechanism studies confirmed that Bmi-1 mediated these effects of miR-495 on MSCs. Conclusion: Taken together, our data demonstrated that miR-495 induced senescence of MSCs may be involved in the pathogenesis of PE.

  5. CDK2 differentially controls normal cell senescence and cancer cell proliferation upon exposure to reactive oxygen species

    International Nuclear Information System (INIS)

    Hwang, Chae Young; Lee, Seung-Min; Park, Sung Sup; Kwon, Ki-Sun

    2012-01-01

    Highlights: ► H 2 O 2 differently adjusted senescence and proliferation in normal and cancer cells. ► H 2 O 2 exposure transiently decreased PCNA levels in normal cells. ► H 2 O 2 exposure transiently increased CDK2 activity in cancer cells. ► p21 Cip1 is likely dispensable when H 2 O 2 induces senescence in normal cells. ► Suggestively, CDK2 and PCNA play critical roles in H 2 O 2 -induced cell fate decision. -- Abstract: Reactive oxygen species modulate cell fate in a context-dependent manner. Sublethal doses of H 2 O 2 decreased the level of proliferating cell nuclear antigen (PCNA) in normal cells (including primary human dermal fibroblasts and IMR-90 cells) without affecting cyclin-dependent kinase 2 (CDK2) activity, leading to cell cycle arrest and subsequent senescence. In contrast, exposure of cancer cells (such as HeLa and MCF7 cells) to H 2 O 2 increased CDK2 activity with no accompanying change in the PCNA level, leading to cell proliferation. A CDK2 inhibitor, CVT-313, prevented H 2 O 2 -induced cancer cell proliferation. These results support the notion that the cyclin/CDK2/p21 Cip1 /PCNA complex plays an important role as a regulator of cell fate decisions.

  6. Identification of novel senescence-associated genes in ionizing radiation-induced senescent carcinoma cells

    International Nuclear Information System (INIS)

    Lee, Jae Seon; Kim, Bong Cho; Han, Na Kyung; Hong, Mi Na; Park, Su Min; Yoo, Hee Jung; Chu, In Sun; Lee, Sun Hee

    2009-01-01

    Cellular senescence is considered as a defense mechanism to prevent tumorigenesis. Ionizing radiation (IR) induces stress-induced premature senescence as well as apoptosis in various cancer cells. Senescent cells undergo functional and morphological changes including large and flattened cell shape, senescence-associated β-galactosidase (SA-βGal) activity, and altered gene expressions. Even with the recent findings of several gene expression profiles and supporting functional data, it is obscure that mechanism of IR-induced premature senescence in cancer cells. We performed microarray analysis to identify the common regulated genes in ionizing radiation-induced prematurely senescent human carcinoma cell lines

  7. New agents that target senescent cells: the flavone, fisetin, and the BCL-XL inhibitors, A1331852 and A1155463.

    Science.gov (United States)

    Zhu, Yi; Doornebal, Ewald J; Pirtskhalava, Tamar; Giorgadze, Nino; Wentworth, Mark; Fuhrmann-Stroissnigg, Heike; Niedernhofer, Laura J; Robbins, Paul D; Tchkonia, Tamara; Kirkland, James L

    2017-03-08

    Senescent cells accumulate with aging and at sites of pathology in multiple chronic diseases. Senolytics are drugs that selectively promote apoptosis of senescent cells by temporarily disabling the pro-survival pathways that enable senescent cells to resist the pro-apoptotic, pro-inflammatory factors that they themselves secrete. Reducing senescent cell burden by genetic approaches or by administering senolytics delays or alleviates multiple age- and disease-related adverse phenotypes in preclinical models. Reported senolytics include dasatinib, quercetin, navitoclax (ABT263), and piperlongumine. Here we report that fisetin, a naturally-occurring flavone with low toxicity, and A1331852 and A1155463, selective BCL-X L inhibitors that may have less hematological toxicity than the less specific BCL-2 family inhibitor navitoclax, are senolytic. Fisetin selectively induces apoptosis in senescent but not proliferating human umbilical vein endothelial cells (HUVECs). It is not senolytic in senescent IMR90 cells, a human lung fibroblast strain, or primary human preadipocytes. A1331852 and A1155463 are senolytic in HUVECs and IMR90 cells, but not preadipocytes. These agents may be better candidates for eventual translation into clinical interventions than some existing senolytics, such as navitoclax, which is associated with hematological toxicity.

  8. Identification and characterization of secretory proteins during ionizing radiation-induced premature senescence

    International Nuclear Information System (INIS)

    Han, Na Kyung; Hong, Mi Na; Jung, Seung Hee; Kang, Kyoung Ah; Lee, Jae Seon; Chi, Seong Gil

    2011-01-01

    Cellular senescence was first described by Hayflick and Moorhead in 1961 who observed that cultures of normal human fibroblasts had a limited replicative potential and eventually became irreversibly arrest. The majority of senescent cells assume a characteristic flattened and enlarged morphological change, senescence associated β alactosidase positivity. Recently a large number of molecular phenotypes such as changes in gene expression, protein processing and chromatin organization have been also described. In contrast to apoptosis, senescence does not destroy the cells but leaves them metabolically and synthetically active and therefore able to affect their microenvironment. In particular, senescent fibroblasts and some cancer cells were found to secrete proteins with known or putative tumor-promoting functions such as growth factors or proteolytic enzymes. However, the knowledge about secreted proteins from senescent tumor cells and their functions to surrounding cells is still lacking. In this study, changes of senescence associated secretory protein expression profile were observed in MCF7 human breast cancer cells exposed to gamma-ray radiation using two dimensional electrophoresis. Also, we identified up-regulated secretory proteins during ionizing radiation-induced cellular senescence. Here, we show that senescent human breast cancer MCF7 cells promote the proliferation, invasion and migration of neighboring cells

  9. Identification and characterization of secretory proteins during ionizing radiation-induced premature senescence

    Energy Technology Data Exchange (ETDEWEB)

    Han, Na Kyung; Hong, Mi Na; Jung, Seung Hee; Kang, Kyoung Ah; Lee, Jae Seon [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Chi, Seong Gil [Korea University, Seoul (Korea, Republic of)

    2011-05-15

    Cellular senescence was first described by Hayflick and Moorhead in 1961 who observed that cultures of normal human fibroblasts had a limited replicative potential and eventually became irreversibly arrest. The majority of senescent cells assume a characteristic flattened and enlarged morphological change, senescence associated {beta} alactosidase positivity. Recently a large number of molecular phenotypes such as changes in gene expression, protein processing and chromatin organization have been also described. In contrast to apoptosis, senescence does not destroy the cells but leaves them metabolically and synthetically active and therefore able to affect their microenvironment. In particular, senescent fibroblasts and some cancer cells were found to secrete proteins with known or putative tumor-promoting functions such as growth factors or proteolytic enzymes. However, the knowledge about secreted proteins from senescent tumor cells and their functions to surrounding cells is still lacking. In this study, changes of senescence associated secretory protein expression profile were observed in MCF7 human breast cancer cells exposed to gamma-ray radiation using two dimensional electrophoresis. Also, we identified up-regulated secretory proteins during ionizing radiation-induced cellular senescence. Here, we show that senescent human breast cancer MCF7 cells promote the proliferation, invasion and migration of neighboring cells

  10. The gene expression program of prostate fibroblast senescence modulates neoplastic epithelial cell proliferation through paracrine mechanisms.

    Science.gov (United States)

    Bavik, Claes; Coleman, Ilsa; Dean, James P; Knudsen, Beatrice; Plymate, Steven; Nelson, Peter S

    2006-01-15

    The greatest risk factor for developing carcinoma of the prostate is advanced age. Potential molecular and physiologic contributors to the frequency of cancer occurrence in older individuals include the accumulation of somatic mutations through defects in genome maintenance, epigenetic gene silencing, oxidative stress, loss of immune surveillance, telomere dysfunction, chronic inflammation, and alterations in tissue microenvironment. In this context, the process of prostate carcinogenesis can be influenced through interactions between intrinsic cellular alterations and the extrinsic microenvironment and macroenvironment, both of which change substantially as a consequence of aging. In this study, we sought to characterize the molecular alterations that occur during the process of prostate fibroblast senescence to identify factors in the aged tissue microenvironment capable of promoting the proliferation and potentially the neoplastic progression of prostate epithelium. We evaluated three mechanisms leading to cell senescence: oxidative stress, DNA damage, and replicative exhaustion. We identified a consistent program of gene expression that includes a subset of paracrine factors capable of influencing adjacent prostate epithelial growth. Both direct coculture and conditioned medium from senescent prostate fibroblasts stimulated epithelial cell proliferation, 3-fold and 2-fold, respectively. The paracrine-acting proteins fibroblast growth factor 7, hepatocyte growth factor, and amphiregulin (AREG) were elevated in the extracellular environment of senescent prostate fibroblasts. Exogenous AREG alone stimulated prostate epithelial cell growth, and neutralizing antibodies and small interfering RNA targeting AREG attenuated, but did not completely abrogate the growth-promoting effects of senescent fibroblast conditioned medium. These results support the concept that aging-related changes in the prostate microenvironment may contribute to the progression of prostate

  11. A comparison of oncogene-induced senescence and replicative senescence: implications for tumor suppression and aging.

    Science.gov (United States)

    Nelson, David M; McBryan, Tony; Jeyapalan, Jessie C; Sedivy, John M; Adams, Peter D

    2014-06-01

    Cellular senescence is a stable proliferation arrest associated with an altered secretory pathway, the senescence-associated secretory phenotype. However, cellular senescence is initiated by diverse molecular triggers, such as activated oncogenes and shortened telomeres, and is associated with varied and complex physiological endpoints, such as tumor suppression and tissue aging. The extent to which distinct triggers activate divergent modes of senescence that might be associated with different physiological endpoints is largely unknown. To begin to address this, we performed gene expression profiling to compare the senescence programs associated with two different modes of senescence, oncogene-induced senescence (OIS) and replicative senescence (RS [in part caused by shortened telomeres]). While both OIS and RS are associated with many common changes in gene expression compared to control proliferating cells, they also exhibit substantial differences. These results are discussed in light of potential physiological consequences, tumor suppression and aging.

  12. Grow-ING, Age-ING and Die-ING: ING proteins link cancer, senescence and apoptosis

    International Nuclear Information System (INIS)

    Russell, Michael; Berardi, Philip; Gong Wei; Riabowol, Karl

    2006-01-01

    The INhibitor of Growth (ING) family of plant homeodomain (PHD) proteins induce apoptosis and regulate gene expression through stress-inducible binding of phospholipids with subsequent nuclear and nucleolar localization. Relocalization occurs concomitantly with interaction with a subset of nuclear proteins, including PCNA, p53 and several regulators of acetylation such as the p300/CBP and PCAF histone acetyltransferases (HATs), as well as the histone deacetylases HDAC1 and hSir2. These interactions alter the localized state of chromatin compaction, subsequently affecting the expression of subsets of genes, including those associated with the stress response (Hsp70), apoptosis (Bax, MDM2) and cell cycle regulation (p21 WAF1 , cyclin B) in a cell- and tissue-specific manner. The expression levels and subcellular localization of ING proteins are altered in a significant number of human cancer types, while the expression of ING isoforms changes during cellular aging, suggesting that ING proteins may play a role in linking cellular transformation and replicative senescence. The variety of functions attributed to ING proteins suggest that this tumor suppressor serves to link the disparate processes of cell cycle regulation, cell suicide and cellular aging through epigenetic regulation of gene expression. This review examines recent findings in the ING field with a focus on the functions of protein-protein interactions involving ING family members and the mechanisms by which these interactions facilitate the various roles that ING proteins play in tumorigenesis, apoptosis and senescence

  13. Mechanisms of decreased intestinal epithelial proliferation and increased apoptosis in murine acute lung injury.

    Science.gov (United States)

    Husain, Kareem D; Stromberg, Paul E; Woolsey, Cheryl A; Turnbull, Isaiah R; Dunne, W Michael; Javadi, Pardis; Buchman, Timothy G; Karl, Irene E; Hotchkiss, Richard S; Coopersmith, Craig M

    2005-10-01

    The aim of this study was to determine the effects of acute lung injury on the gut epithelium and examine mechanisms underlying changes in crypt proliferation and apoptosis. The relationship between severity and timing of lung injury to intestinal pathology was also examined. Randomized, controlled study. University research laboratory. Genetically inbred mice. Following induction of acute lung injury, gut epithelial proliferation and apoptosis were assessed in a) C3H/HeN wild-type and C3H/HeJ mice, which lack functional Toll-like receptor 4 (n = 17); b) C57Bl/6 mice that received monoclonal anti-tumor necrosis factor-alpha or control antibody (n = 22); and c) C57Bl/6 wild-type and transgenic mice that overexpress Bcl-2 in their gut epithelium (n = 21). Intestinal epithelial proliferation and death were also examined in animals with differing degrees of lung inflammation (n = 24) as well as in a time course analysis following a fixed injury (n = 18). Acute lung injury caused decreased proliferation and increased apoptosis in crypt epithelial cells in all animals studied. C3H/HeJ mice had higher levels of proliferation than C3H/HeN animals without additional changes in apoptosis. Anti-tumor necrosis factor-alpha antibody had no effect on gut epithelial proliferation or death. Overexpression of Bcl-2 did not change proliferation despite decreasing gut apoptosis. Proliferation and apoptosis were not correlated to severity of lung injury, as gut alterations were lost in mice with more severe acute lung injury. Changes in both gut epithelial proliferation and death were apparent within 12 hrs, but proliferation was decreased 36 hrs following acute lung injury while apoptosis returned to normal. Acute lung injury causes disparate effects on crypt proliferation and apoptosis, which occur, at least in part, through differing mechanisms involving Toll-like receptor 4 and Bcl-2. Severity of lung injury does not correlate with perturbations in proliferation or death in the

  14. Regiospecific Synthesis of Ring A Fused Withaferin A Isoxazoline Analogues: Induction of Premature Senescence by W-2b in Proliferating Cancer Cells.

    Science.gov (United States)

    Rasool, Faheem; Nayak, Debasis; Katoch, Archana; Faheem, Mir Mohd; Yousuf, Syed Khalid; Hussain, Nazar; Belawal, Chetan; Satti, N K; Goswami, Anindya; Mukherjee, Debaraj

    2017-10-23

    Induction of premature senescence represents a novel functional strategy to curb the uncontrolled proliferation of malignant cancer cells. This study unveils the regiospecific synthesis of novel isoxazoline derivatives condensed to ring A of medicinal plant product Withaferin-A. Intriguingly, the cis fused products with β-oriented hydrogen exhibited excellent cytotoxic activities against proliferating human breast cancer MCF7 and colorectal cancer HCT-116 cells. The most potent derivative W-2b triggered premature senescence along with increase in senescence-associated β-galactosidase activity, G2/M cell cycle arrest, and induction of senescence-specific marker p21 Waf1/Cip1 at its sub-toxic concentration. W-2b conferred a robust increase in phosphorylation of mammalian checkpoint kinase-2 (Chk2) in cancer cells in a dose-dependent manner. Silencing of endogenous Chk2 by siRNA divulged that the amplification of p21 expression and senescence by W-2b was Chk2-dependent. Chk2 activation (either by ectopic overexpression or through treatment with W-2b) suppressed NM23-H1 signaling axis involved in cancer cell proliferation. Finally, W-2b showed excellent in vivo efficacy with 83.8% inhibition of tumor growth at a dose of 25 mg/kg, b.w. in mouse mammary carcinoma model. Our study claims that W-2b could be a potential candidate to limit aberrant cellular proliferation rendering promising improvement in the treatment regime in cancer patients.

  15. MicroRNA miR-125b induces senescence in human melanoma cells.

    Science.gov (United States)

    Glud, Martin; Manfé, Valentina; Biskup, Edyta; Holst, Line; Dirksen, Anne Marie Ahlburg; Hastrup, Nina; Nielsen, Finn C; Drzewiecki, Krzysztof T; Gniadecki, Robert

    2011-06-01

    MicroRNAs (miRNAs) are small noncoding RNA molecules involved in gene regulation. Aberrant expression of miRNA has been associated with the development or progression of several diseases, including cancer. In a previous study, we found that the expression of miRNA-125b (miR-125b) was two-fold lower in malignant melanoma producing lymph node micrometastases than in nonmetastasizing tumors. To get further insight into the functional role of miR-125b, we assessed whether its overexpression or silencing affects apoptosis, proliferation, or senescence in melanoma cell lines. We showed that overexpression of miR-125b induced typical senescent cell morphology, including increased cytoplasmatic/nucleus ratio and intensive cytoplasmatic β-galactosidase expression. In contrast, inhibition of miR-125b resulted in 30-35% decreased levels of spontaneous apoptosis. We propose that downregulation of miR-125b in an early cutaneous malignant melanoma can contribute to the increased metastatic capability of this tumor.

  16. Correlation of lung surface area to apoptosis and proliferation in human emphysema.

    Science.gov (United States)

    Imai, K; Mercer, B A; Schulman, L L; Sonett, J R; D'Armiento, J M

    2005-02-01

    Pulmonary emphysema is associated with alterations in matrix proteins and protease activity. These alterations may be linked to programmed cell death by apoptosis, potentially influencing lung architecture and lung function. To evaluate apoptosis in emphysema, lung tissue was analysed from 10 emphysema patients and six individuals without emphysema (normal). Morphological analysis revealed alveolar cells in emphysematous lungs with convoluted nuclei characteristic of apoptosis. DNA fragmentation was detected using terminal deoxynucleotide transferase-mediated dUTP nick-end labelling (TUNEL) and gel electrophoresis. TUNEL revealed higher apoptosis in emphysematous than normal lungs. Markers of apoptosis, including active caspase-3, proteolytic fragment of poly (ADP-ribose) polymerase, Bax and Bad, were detected in emphysematous lungs. Linear regression showed that apoptosis was inversely correlated with surface area. Emphysematous lungs demonstrated lower surface areas and increased cell proliferation. There was no correlation between apoptosis and proliferation, suggesting that, although both events increase during emphysema, they are not in equilibrium, potentially contributing to reduced lung surface area. In summary, cell-based mechanisms associated with emphysematous parenchymal damage include increased apoptosis and cell proliferation. Apoptosis correlated with airspace enlargement, supporting epidemiological evidence of the progressive nature of emphysema. These data extend the understanding of cell dynamics and structural changes within the lung during emphysema pathogenesis.

  17. Oridonin induces apoptosis and senescence in colorectal cancer cells by increasing histone hyperacetylation and regulation of p16, p21, p27 and c-myc

    International Nuclear Information System (INIS)

    Gao, Feng-Hou; Liu, Feng; Zhao, Ying-Zheng; Fang, Yong; Chen, Fang-Yuan; Wu, Ying-Li; Hu, Xiao-Hui; Li, Wei; Liu, Hua; Zhang, Yan-Jie; Guo, Zhu-Ying; Xu, Mang-Hua; Wang, Shi-Ting; Jiang, Bin

    2010-01-01

    Oridonin, a tetracycline diterpenoid compound, has the potential antitumor activities. Here, we evaluate the antitumor activity and action mechanisms of oridonin in colorectal cancer. Effects of oridonin on cell proliferation were determined by using a CCK-8 Kit. Cell cycle distribution was determined by flow cytometry. Apoptosis was examined by analyzing subdiploid population and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay. Senescent cells were determined by senescence-associated β-galactosidase activity analysis. Semi-quantitative RT-PCR was used to examine the changes of mRNA of p16, p21, p27 and c-myc. The concomitant changes of protein expression were analyzed with Western blot. Expression of AcH3 and AcH4 were examined by immunofluorescence staining and Western blots. Effects of oridonin on colony formation of SW1116 were examined by Soft Agar assay. The in vivo efficacy of oridonin was detected using a xenograft colorectal cancer model in nude mice. Oridonin induced potent growth inhibition, cell cycle arrest, apoptosis, senescence and colony-forming inhibition in three colorectal cancer cell lines in a dose-dependent manner in vitro. Daily i.p. injection of oridonin (6.25, 12.5 or 25 mg/kg) for 28 days significantly inhibited the growth of SW1116 s.c. xenografts in BABL/C nude mice. With western blot and reverse transcription-PCR, we further showed that the antitumor activities of oridonin correlated with induction of histone (H3 and H4) hyperacetylation, activation of p21, p27 and p16, and suppression of c-myc expression. Oridonin possesses potent in vitro and in vivo anti-colorectal cancer activities that correlated with induction of histone hyperacetylation and regulation of pathways critical for maintaining growth inhibition and cell cycle arrest. Therefore, oridonin may represent a novel therapeutic option in colorectal cancer treatment

  18. Oridonin induces apoptosis and senescence in colorectal cancer cells by increasing histone hyperacetylation and regulation of p16, p21, p27 and c-myc

    Directory of Open Access Journals (Sweden)

    Zhao Ying-Zheng

    2010-11-01

    Full Text Available Abstract Background Oridonin, a tetracycline diterpenoid compound, has the potential antitumor activities. Here, we evaluate the antitumor activity and action mechanisms of oridonin in colorectal cancer. Methods Effects of oridonin on cell proliferation were determined by using a CCK-8 Kit. Cell cycle distribution was determined by flow cytometry. Apoptosis was examined by analyzing subdiploid population and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay. Senescent cells were determined by senescence-associated β-galactosidase activity analysis. Semi-quantitative RT-PCR was used to examine the changes of mRNA of p16, p21, p27 and c-myc. The concomitant changes of protein expression were analyzed with Western blot. Expression of AcH3 and AcH4 were examined by immunofluorescence staining and Western blots. Effects of oridonin on colony formation of SW1116 were examined by Soft Agar assay. The in vivo efficacy of oridonin was detected using a xenograft colorectal cancer model in nude mice. Results Oridonin induced potent growth inhibition, cell cycle arrest, apoptosis, senescence and colony-forming inhibition in three colorectal cancer cell lines in a dose-dependent manner in vitro. Daily i.p. injection of oridonin (6.25, 12.5 or 25 mg/kg for 28 days significantly inhibited the growth of SW1116 s.c. xenografts in BABL/C nude mice. With western blot and reverse transcription-PCR, we further showed that the antitumor activities of oridonin correlated with induction of histone (H3 and H4 hyperacetylation, activation of p21, p27 and p16, and suppression of c-myc expression. Conclusion Oridonin possesses potent in vitro and in vivo anti-colorectal cancer activities that correlated with induction of histone hyperacetylation and regulation of pathways critical for maintaining growth inhibition and cell cycle arrest. Therefore, oridonin may represent a novel therapeutic option in colorectal cancer treatment.

  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. Cellular Senescence Promotes Adverse Effects of Chemotherapy and Cancer Relapse

    NARCIS (Netherlands)

    Demaria, Marco; O'Leary, Monique N.; Chang, Jianhui; Shao, Lijian; Liu, Su; Alimirah, Fatouma; Koenig, Kristin; Le, Catherine; Mitin, Natalia; Deal, Allison M.; Alston, Shani; Academia, Emmeline C.; Kilmarx, Sumner; Valdovinos, Alexis; Wang, Boshi; de Bruin, Alain; Kennedy, Brian K.; Melov, Simon; Zhou, Daohong; Sharpless, Norman E.; Muss, Hyman; Campisi, Judith

    Cellular senescence suppresses cancer by irreversibly arresting cell proliferation. Senescent cells acquire a proinfl ammatory senescence-associated secretory phenotype. Many genotoxic chemotherapies target proliferating cells nonspecifi cally, often with adverse reactions. In accord with prior

  1. The role of nibrin in doxorubicin-induced apoptosis and cell senescence in Nijmegen Breakage Syndrome patients lymphocytes.

    Directory of Open Access Journals (Sweden)

    Olga Alster

    Full Text Available Nibrin plays an important role in the DNA damage response (DDR and DNA repair. DDR is a crucial signaling pathway in apoptosis and senescence. To verify whether truncated nibrin (p70, causing Nijmegen Breakage Syndrome (NBS, is involved in DDR and cell fate upon DNA damage, we used two (S4 and S3R spontaneously immortalized T cell lines from NBS patients, with the founding mutation and a control cell line (L5. S4 and S3R cells have the same level of p70 nibrin, however p70 from S4 cells was able to form more complexes with ATM and BRCA1. Doxorubicin-induced DDR followed by cell senescence could only be observed in L5 and S4 cells, but not in the S3R ones. Furthermore the S3R cells only underwent cell death, but not senescence after doxorubicin treatment. In contrary to doxorubicin treatment, cells from all three cell lines were able to activate the DDR pathway after being exposed to γ-radiation. Downregulation of nibrin in normal human vascular smooth muscle cells (VSMCs did not prevent the activation of DDR and induction of senescence. Our results indicate that a substantially reduced level of nibrin or its truncated p70 form is sufficient to induce DNA-damage dependent senescence in VSMCs and S4 cells, respectively. In doxorubicin-treated S3R cells DDR activation was severely impaired, thus preventing the induction of senescence.

  2. Cellular Senescence: A Translational Perspective

    Directory of Open Access Journals (Sweden)

    James L. Kirkland

    2017-07-01

    Full Text Available Cellular senescence entails essentially irreversible replicative arrest, apoptosis resistance, and frequently acquisition of a pro-inflammatory, tissue-destructive senescence-associated secretory phenotype (SASP. Senescent cells accumulate in various tissues with aging and at sites of pathogenesis in many chronic diseases and conditions. The SASP can contribute to senescence-related inflammation, metabolic dysregulation, stem cell dysfunction, aging phenotypes, chronic diseases, geriatric syndromes, and loss of resilience. Delaying senescent cell accumulation or reducing senescent cell burden is associated with delay, prevention, or alleviation of multiple senescence-associated conditions. We used a hypothesis-driven approach to discover pro-survival Senescent Cell Anti-apoptotic Pathways (SCAPs and, based on these SCAPs, the first senolytic agents, drugs that cause senescent cells to become susceptible to their own pro-apoptotic microenvironment. Several senolytic agents, which appear to alleviate multiple senescence-related phenotypes in pre-clinical models, are beginning the process of being translated into clinical interventions that could be transformative.

  3. A decrease in cyclin B1 levels leads to polyploidization in DNA damage-induced senescence.

    Science.gov (United States)

    Kikuchi, Ikue; Nakayama, Yuji; Morinaga, Takao; Fukumoto, Yasunori; Yamaguchi, Naoto

    2010-05-04

    Adriamycin, an anthracycline antibiotic, has been used for the treatment of various types of tumours. Adriamycin induces at least two distinct types of growth repression, such as senescence and apoptosis, in a concentration-dependent manner. Cellular senescence is a condition in which cells are unable to proliferate further, and senescent cells frequently show polyploidy. Although abrogation of cell division is thought to correlate with polyploidization, the mechanisms underlying induction of polyploidization in senescent cells are largely unclear. We wished, therefore, to explore the role of cyclin B1 level in polyploidization of Adriamycin-induced senescent cells. A subcytotoxic concentration of Adriamycin induced polyploid cells having the features of senescence, such as flattened and enlarged cell shape and activated beta-galactosidase activity. In DNA damage-induced senescent cells, the levels of cyclin B1 were transiently increased and subsequently decreased. The decrease in cyclin B1 levels occurred in G2 cells during polyploidization upon treatment with a subcytotoxic concentration of Adriamycin. In contrast, neither polyploidy nor a decrease in cyclin B1 levels was induced by treatment with a cytotoxic concentration of Adriamycin. These results suggest that a decrease in cyclin B1 levels is induced by DNA damage, resulting in polyploidization in DNA damage-induced senescence.

  4. Stable SREBP-1a knockdown decreases the cell proliferation rate in human preadipocyte cells without inducing senescence

    International Nuclear Information System (INIS)

    Alvarez, María Soledad; Fernandez-Alvarez, Ana; Cucarella, Carme; Casado, Marta

    2014-01-01

    Highlights: • SGBS cells mostly expressed SREBP-1a variant. • SREBP-1a knockdown decreased the proliferation of SGBS cells without inducing senescence. • We have identified RBBP8 and CDKN3 genes as potential SREBP-1a targets. - Abstract: Sterol regulatory element binding proteins (SREBP), encoded by the Srebf1 and Srebf2 genes, are important regulators of genes involved in cholesterol and fatty acid metabolism. Whereas SREBP-2 controls the cholesterol synthesis, SREBP-1 proteins (-1a and -1c) function as the central hubs in lipid metabolism. Despite the key function of these transcription factors to promote adipocyte differentiation, the roles of SREBP-1 proteins during the preadipocyte state remain unknown. Here, we evaluate the role of SREBP-1 in preadipocyte proliferation using RNA interference technology. Knockdown of the SREBP-1a gene decreased the proliferation rate in human SGBS preadipocyte cell strain without inducing senescence. Furthermore, our data identified retinoblastoma binding protein 8 and cyclin-dependent kinase inhibitor 3 genes as new potential SREBP-1 targets, in addition to cyclin-dependent kinase inhibitor 1A which had already been described as a gene regulated by SREBP-1a. These data suggested a new role of SREBP-1 in adipogenesis via regulation of preadipocyte proliferation

  5. Stable SREBP-1a knockdown decreases the cell proliferation rate in human preadipocyte cells without inducing senescence

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez, María Soledad [Instituto de Biomedicina de Valencia (IBV-CSIC), Jaime Roig 11, E-46010 Valencia (Spain); Fernandez-Alvarez, Ana [Fundación Instituto Leloir, IIBBA-CONICET, Av. Patricias Argentinas 435, Ciudad Autónoma de Buenos Aires C1405BWE (Argentina); Cucarella, Carme [Instituto de Biomedicina de Valencia (IBV-CSIC), Jaime Roig 11, E-46010 Valencia (Spain); Casado, Marta, E-mail: mcasado@ibv.csic.es [Instituto de Biomedicina de Valencia (IBV-CSIC), Jaime Roig 11, E-46010 Valencia (Spain)

    2014-04-25

    Highlights: • SGBS cells mostly expressed SREBP-1a variant. • SREBP-1a knockdown decreased the proliferation of SGBS cells without inducing senescence. • We have identified RBBP8 and CDKN3 genes as potential SREBP-1a targets. - Abstract: Sterol regulatory element binding proteins (SREBP), encoded by the Srebf1 and Srebf2 genes, are important regulators of genes involved in cholesterol and fatty acid metabolism. Whereas SREBP-2 controls the cholesterol synthesis, SREBP-1 proteins (-1a and -1c) function as the central hubs in lipid metabolism. Despite the key function of these transcription factors to promote adipocyte differentiation, the roles of SREBP-1 proteins during the preadipocyte state remain unknown. Here, we evaluate the role of SREBP-1 in preadipocyte proliferation using RNA interference technology. Knockdown of the SREBP-1a gene decreased the proliferation rate in human SGBS preadipocyte cell strain without inducing senescence. Furthermore, our data identified retinoblastoma binding protein 8 and cyclin-dependent kinase inhibitor 3 genes as new potential SREBP-1 targets, in addition to cyclin-dependent kinase inhibitor 1A which had already been described as a gene regulated by SREBP-1a. These data suggested a new role of SREBP-1 in adipogenesis via regulation of preadipocyte proliferation.

  6. Simultaneous Increases in Proliferation and Apoptosis of Vascular Smooth Muscle Cells Accelerate Diabetic Mouse Venous Atherosclerosis

    Science.gov (United States)

    Liu, Shuying; Zhang, Zhengyu; Wang, Jingjing; Zhou, Yuhuan; Liu, Kefeng; Huang, Jintao; Chen, Dadi; Wang, Junmei; Li, Chaohong

    2015-01-01

    Aims This study was designed to demonstrate simultaneous increases in proliferation and apoptosis of vascular smooth muscle cells (VSMCs) leading to accelerated vein graft remodeling and to explore the underlying mechanisms. Methods Vein grafts were performed in non-diabetic and diabetic mice. The cultured quiescent VSMCs were subjected to mechanical stretch stress (SS) and/or advanced glycosylation end products (AGEs). Harvested vein grafts and treated VSMCs were used to detect cell proliferation, apoptosis, mitogen-activated protein kinases (MAPKs) activation and SM-α-actin expression. Results Significantly thicker vessel walls and greater increases in proliferation and apoptosis were observed in diabetic vein grafts than those in non-diabetic. Both SS and AGEs were found to induce different activation of three members of MAPKs and simultaneous increases in proliferation and apoptosis of VSMCs, and combined treatment with both had a synergistic effect. VSMCs with strong SM-α-actin expression represented more activated JNKs or p38MAPK, and cell apoptosis, while the cells with weak SM-α-actin expression demonstrated preferential activation of ERKs and cell proliferation. In contrast, inhibition of MAPKs signals triggered significant decreases in VSMC proliferation, and apoptosis. Treatment of the cells with RNA interference of receptor of AGEs (RAGE) also resulted in significant decreases in both proliferation and apoptosis. Conclusions Increased pressure-induced SS triggers simultaneous increases in proliferation and apoptosis of VSMCs in the vein grafts leading to vein arterializations, which can be synergistically accelerated by high glucose-induced AGEs resulting in vein graft atherosclerosis. Either SS or AGEs and their combination induce simultaneous increases in proliferation and apoptosis of VSMCs via different activation of three members of MAPKs resulting from different VSMC subtypes classified by SM-α-actin expression levels. PMID:26488175

  7. Premature aging/senescence in cancer cells facing therapy: good or bad?

    Science.gov (United States)

    Gonzalez, Llilians Calvo; Ghadaouia, Sabrina; Martinez, Aurélie; Rodier, Francis

    2016-02-01

    Normal and cancer cells facing their demise following exposure to radio-chemotherapy can actively participate in choosing their subsequent fate. These programmed cell fate decisions include true cell death (apoptosis-necroptosis) and therapy-induced cellular senescence (TIS), a permanent "proliferative arrest" commonly portrayed as premature cellular aging. Despite a permanent loss of proliferative potential, senescent cells remain viable and are highly bioactive at the microenvironment level, resulting in a prolonged impact on tissue architecture and functions. Cellular senescence is primarily documented as a tumor suppression mechanism that prevents cellular transformation. In the context of normal tissues, cellular senescence also plays important roles in tissue repair, but contributes to age-associated tissue dysfunction when senescent cells accumulate. Theoretically, in multi-step cancer progression models, cancer cells have already bypassed cellular senescence during their immortalization step (see hallmarks of cancer). It is then perhaps surprising to find that cancer cells often retain the ability to undergo TIS, or premature aging. This occurs because cellular senescence results from multiple signalling pathways, some retained in cancer cells, aiming to prevent cell cycle progression in damaged cells. Since senescent cancer cells persist after therapy and secrete an array of cytokines and growth factors that can modulate the tumor microenvironment, these cells may have beneficial and detrimental effects regarding immune modulation and survival of remaining proliferation-competent cancer cells. Similarly, while normal cells undergoing senescence are believed to remain indefinitely growth arrested, whether this is true for senescent cancer cells remains unclear, raising the possibility that these cells may represent a reservoir for cancer recurrence after treatment. This review discusses our current knowledge on cancer cell senescence and highlight questions

  8. Effect of 103Pd on proliferation and apoptosis of vascular smooth muscle cells

    International Nuclear Information System (INIS)

    Luo Quanyong; Zhu Jun; Lu Hankui; Zhu Ruisen

    2003-01-01

    This study aimed at the effect of γ-emitting radionuclide 103 Pd on the proliferation and apoptosis of vascular SMCs (smooth muscle cells) in vitro. The cavy aortic SMCs were cultured with culture medium M-199. The experiments were carried out in two groups, one for proliferation test and the other for apoptosis test. In each group, 103 Pd solutions with various radioactivities were respectively added to the culture solution to irradiate SMCs for 72 h, while non-radioactive palladium solution was added to the control. 3 H-thymidine incorporation test and liquid scintillator were used to detect the effect of 103 Pd on the proliferation of SMCs. Flow cytometer was used to detect the apoptotic SMCs. The inhibition rate of SMCs proliferation by 1.85 MBq 103 Pd solution was 2.3%, which was not significant, while the inhibition rate increased from 41.6% to 91.3% as the 103 Pd activity increased from 7.40 MBq to 37 MBq. The apoptosis rate of SMCs was extremely low (less than 4.0%) by 103 Pd with activity from 1.85 MBq to 37 MBq. The results suggest that the proliferation of SMCs can be repressed effectively in a dose-dependent fashion by 103 Pd in vitro. The mechanism of its inhibiting over neointima proliferation is likely to inhibit SMCs proliferation rather than to induce its apoptosis by 103 Pd. 103 Pd can be used as a γ-emitting intravascular brachytherapy radionuclide to inhibit SMCs proliferation

  9. The effect of 648 nm diode laser irradiation on second messengers in senescent human keratinocytes

    Science.gov (United States)

    Hawkins Evans, D.; Abrahamse, H.

    2009-02-01

    Background/purpose: Stress induced premature senescence (SIPS) is defined as the long-term effect of subcytotoxic stress on proliferative cell types. Cells in SIPS display differences at the level of protein expression which affect energy metabolism, defense systems, redox potential, cell morphology and transduction pathways. This study aimed to determine the effect of laser irradiation on second messengers in senescent cells and to establish if that effect can be directly linked to changes in cellular function such as cell viability or proliferation. Materials and Methods: Human keratinocyte cell cultures were modified to induce premature senescence using repeated sub-lethal stresses of 200 uM H2O2 or 5% OH every day for four days with two days recovery. SIPS was confirmed by senescence-associated β-galactosidase staining. Control conditions included normal, repeated stress of 500 uM H2O2 to induce apoptosis and 200 uM PBN as an anti-oxidant or free radical scavenger. Cells were irradiated with 1.5 J/cm2 on day 1 and 4 using a 648 nm diode laser (3.3 mW/cm2) and cellular responses were measured 1 h post irradiation. The affect on second messengers was assessed by measuring cAMP, cGMP, nitric oxide and intracellular calcium (Ca2+) while functional changes were assessed using cell morphology, ATP cell viability, LDH membrane integrity and WST-1 cell proliferation. Results: Results indicate an increase in NO and a decrease in cGMP and Ca2+ in 200 uM H2O2 irradiated cells while PBN irradiated cells showed a decrease in cAMP and an increase in ATP viability and cell proliferation. Conclusion: Laser irradiation influences cell signaling which ultimately changes the biological function of senescent cells. If laser therapy can stimulate the biological function of senescent cells it may be beneficial to conditions such as immune senescence, skin ageing, muscle atrophy, premature ageing of arteries in patients with advanced heart disease, neurodegenerative disorders and

  10. Protective role of klotho protein on epithelial cells upon co-culture with activated or senescent monocytes

    Energy Technology Data Exchange (ETDEWEB)

    Mytych, Jennifer, E-mail: jennifermytych@gmail.com [Institute of Applied Biotechnology and Basic Sciences, University of Rzeszow, Werynia 502, 36-100 Kolbuszowa (Poland); Centre of Applied Biotechnology and Basic Sciences, University of Rzeszow, Werynia 502, 36-100 Kolbuszowa (Poland); Wos, Izabela; Solek, Przemyslaw; Koziorowski, Marek [Institute of Applied Biotechnology and Basic Sciences, University of Rzeszow, Werynia 502, 36-100 Kolbuszowa (Poland); Centre of Applied Biotechnology and Basic Sciences, University of Rzeszow, Werynia 502, 36-100 Kolbuszowa (Poland)

    2017-01-15

    Monocytes ensure proper functioning and maintenance of epithelial cells, while good condition of monocytes is a key factor of these interactions. Although, it was shown that in some circumstances, a population of altered monocytes may appear, there is no data regarding their effect on epithelial cells. In this study, using direct co-culture model with LPS-activated and Dox-induced senescent THP-1 monocytes, we reported for the first time ROS-induced DNA damage, reduced metabolic activity, proliferation inhibition and cell cycle arrest followed by p16-, p21- and p27-mediated DNA damage response pathways activation, premature senescence and apoptosis induction in HeLa cells. Also, we show that klotho protein possessing anti-aging and anti-inflammatory characteristics reduced cytotoxic and genotoxic events by inhibition of insulin/IGF-IR and downregulation of TRF1 and TRF2 proteins. Therefore, klotho protein could be considered as a protective factor against changes caused by altered monocytes in epithelial cells. - Highlights: • Activated and senescent THP-1 monocytes induced cyto- and genotoxicity in HeLa cells. • Altered monocytes provoked oxidative and nitrosative stress-induced DNA damage. • DNA damage activated DDR pathways and lead to premature senescence and apoptosis. • Klotho reduced ROS/RNS-mediated toxicity through insulin/IGF-IR pathway inhibition. • Klotho protects HeLa cells from cyto- and genotoxicity induced by altered monocytes.

  11. Protective role of klotho protein on epithelial cells upon co-culture with activated or senescent monocytes

    International Nuclear Information System (INIS)

    Mytych, Jennifer; Wos, Izabela; Solek, Przemyslaw; Koziorowski, Marek

    2017-01-01

    Monocytes ensure proper functioning and maintenance of epithelial cells, while good condition of monocytes is a key factor of these interactions. Although, it was shown that in some circumstances, a population of altered monocytes may appear, there is no data regarding their effect on epithelial cells. In this study, using direct co-culture model with LPS-activated and Dox-induced senescent THP-1 monocytes, we reported for the first time ROS-induced DNA damage, reduced metabolic activity, proliferation inhibition and cell cycle arrest followed by p16-, p21- and p27-mediated DNA damage response pathways activation, premature senescence and apoptosis induction in HeLa cells. Also, we show that klotho protein possessing anti-aging and anti-inflammatory characteristics reduced cytotoxic and genotoxic events by inhibition of insulin/IGF-IR and downregulation of TRF1 and TRF2 proteins. Therefore, klotho protein could be considered as a protective factor against changes caused by altered monocytes in epithelial cells. - Highlights: • Activated and senescent THP-1 monocytes induced cyto- and genotoxicity in HeLa cells. • Altered monocytes provoked oxidative and nitrosative stress-induced DNA damage. • DNA damage activated DDR pathways and lead to premature senescence and apoptosis. • Klotho reduced ROS/RNS-mediated toxicity through insulin/IGF-IR pathway inhibition. • Klotho protects HeLa cells from cyto- and genotoxicity induced by altered monocytes.

  12. Effect of triptolide on proliferation and apoptosis of angiotensin II ...

    African Journals Online (AJOL)

    Background: The effect of triptolide (TPL) on cardiac fibroblasts (CFbs) and cardiac fibrosis remain unknown till now. This study was conducted to explore the effects of TPL on proliferation and apoptosis of angiotensin II (Ang II)-induced CFbs. Materials and Methods: Ang II was used to promote proliferation of CFbs.

  13. Proteomic Analysis Reveals a Role for Bcl2-associated Athanogene 3 and Major Vault Protein in Resistance to Apoptosis in Senescent Cells by Regulating ERK1/2 Activation*

    Science.gov (United States)

    Pasillas, Martina P.; Shields, Sarah; Reilly, Rebecca; Strnadel, Jan; Behl, Christian; Park, Robin; Yates, John R.; Klemke, Richard; Gonias, Steven L.; Coppinger, Judith A.

    2015-01-01

    Senescence is a prominent solid tumor response to therapy in which cells avoid apoptosis and instead enter into prolonged cell cycle arrest. We applied a quantitative proteomics screen to identify signals that lead to therapy-induced senescence and discovered that Bcl2-associated athanogene 3 (Bag3) is up-regulated after adriamycin treatment in MCF7 cells. Bag3 is a member of the BAG family of co-chaperones that interacts with Hsp70. Bag3 also regulates major cell-signaling pathways. Mass spectrometry analysis of the Bag3 Complex revealed a novel interaction between Bag3 and Major Vault Protein (MVP). Silencing of Bag3 or MVP shifts the cellular response to adriamycin to favor apoptosis. We demonstrate that Bag3 and MVP contribute to apoptosis resistance in therapy-induced senescence by increasing the level of activation of extracellular signal-regulated kinase1/2 (ERK1/2). Silencing of either Bag3 or MVP decreased ERK1/2 activation and promoted apoptosis in adriamycin-treated cells. An increase in nuclear accumulation of MVP is observed during therapy-induced senescence and the shift in MVP subcellular localization is Bag3-dependent. We propose a model in which Bag3 binds to MVP and facilitates MVP accumulation in the nucleus, which sustains ERK1/2 activation. We confirmed that silencing of Bag3 or MVP shifts the response toward apoptosis and regulates ERK1/2 activation in a panel of diverse breast cancer cell lines. This study highlights Bag3-MVP as an important complex that regulates a potent prosurvival signaling pathway and contributes to chemotherapy resistance in breast cancer. PMID:24997994

  14. Diffuse colonies of human skin fibroblasts in relation to cellular senescence and proliferation.

    Science.gov (United States)

    Zorin, Vadim; Zorina, Alla; Smetanina, Nadezhda; Kopnin, Pavel; Ozerov, Ivan V; Leonov, Sergey; Isaev, Artur; Klokov, Dmitry; Osipov, Andreyan N

    2017-05-16

    Development of personalized skin treatment in medicine and skin care may benefit from simple and accurate evaluation of the fraction of senescent skin fibroblasts that lost their proliferative capacity. We examined whether enriched analysis of colonies formed by primary human skin fibroblasts, a simple and widely available cellular assay, could reveal correlations with the fraction of senescent cells in heterogenic cell population. We measured fractions of senescence associated β-galactosidase (SA-βgal) positive cells in either mass cultures or colonies of various morphological types (dense, mixed and diffuse) formed by skin fibroblasts from 10 human donors. Although the donors were chosen to be within the same age group (33-54 years), the colony forming efficiency of their fibroblasts (ECO-f) and the percentage of dense, mixed and diffuse colonies varied greatly among the donors. We showed, for the first time, that the SA-βgal positive fraction was the largest in diffuse colonies, confirming that they originated from cells with the least proliferative capacity. The percentage of diffuse colonies was also found to correlate with the SA-βgal positive cells in mass culture. Using Ki67 as a cell proliferation marker, we further demonstrated a strong inverse correlation (r=-0.85, p=0.02) between the percentage of diffuse colonies and the fraction of Ki67+ cells. Moreover, a significant inverse correlation (r=-0.94, p=0.0001) between the percentage of diffuse colonies and ECO-f was found. Our data indicate that quantification of a fraction of diffuse colonies may provide a simple and useful method to evaluate the extent of cellular senescence in human skin fibroblasts.

  15. Senescence, apoptosis or autophagy? When a damaged cell must decide its path--a mini-review.

    Science.gov (United States)

    Vicencio, José Miguel; Galluzzi, Lorenzo; Tajeddine, Nicolas; Ortiz, Carla; Criollo, Alfredo; Tasdemir, Ezgi; Morselli, Eugenia; Ben Younes, Amena; Maiuri, Maria Chiara; Lavandero, Sergio; Kroemer, Guido

    2008-01-01

    Many features of aging result from the incapacity of cells to adapt to stress conditions. When damage accumulates irreversibly, mitotic cells from renewable tissues rely on either of two mechanisms to avoid replication. They can permanently arrest the cell cycle (cellular senescence) or trigger cell death programs. Apoptosis (self-killing) is the best-described form of programmed cell death, but autophagy (self-eating), which is a lysosomal degradation pathway essential for homeostasis, reportedly contributes to cell death as well. Unlike mitotic cells, postmitotic cells like neurons or cardiomyocytes cannot become senescent since they are already terminally differentiated. The fate of these cells entirely depends on their ability to cope with stress. Autophagy then operates as a major homeostatic mechanism to eliminate damaged organelles, long-lived or aberrant proteins and superfluous portions of the cytoplasm. In this mini-review, we briefly summarize the molecular networks that allow damaged cells either to adapt to stress or to engage in programmed-cell-death pathways. (c) 2008 S. Karger AG, Basel.

  16. TFF1 inhibits proliferation and induces apoptosis of gastric cancer cells in vitro

    Directory of Open Access Journals (Sweden)

    Yanli Ge

    2012-05-01

    Full Text Available Trefoil Factor Family (TFF plays an essential role in the intestinal epithelial restitution, but the relationship between TFF1 and gastric cancer (GC is still unclear. The present study aimed to determine the role of TFF1 in repairing gastric mucosa and in the pathogenesis of GC.The TFF1 expression in different gastric mucosas was measured with immunohistochemistry. Then, siRNA targeting TFF1 or plasmids expressing TFF1 gene were transfected into BGC823 cells, SGC7901 cells and GES-1 cells. The cell proliferation was detected with MTT assay and apoptosis and cell cycle measured by flow cytometry.From normal gastric mucosa to mucosa with dysplasia and to gastric cancer, the TFF1 expression had a decreasing trend. Down-regulation of TFF1 expression significantly reduced the apoptosis of three cell lines and markedly facilitated their proliferation but had no significant effect on cell cycle. Over-expression of TFF1 could promote apoptosis of three cell lines and inhibit proliferation but had no pronounced effect on cell cycle. TFF1 can inhibit proliferation and induce apoptosis of GC cells in vitro.

  17. Six2 Is a Coordinator of LiCl-Induced Cell Proliferation and Apoptosis

    Directory of Open Access Journals (Sweden)

    Jianing Liu

    2016-09-01

    Full Text Available The metanephric mesenchyme (MM cells are a subset of kidney progenitor cells and play an essential role in mesenchymal-epithelial transition (MET, the key step of nephron generation. Six2, a biological marker related to Wnt signaling pathway, promotes the proliferation, inhibits the apoptosis and maintains the un-differentiation of MM cells. Besides, LiCl is an activator of Wnt signaling pathway. However, the role of LiCl in cellular regulation of MM cells remains unclear, and the relationship between LiCl and Six2 in this process is also little known. Here, we performed EdU assay and flow cytometry assay to, respectively, detect the proliferation and apoptosis of MM cells treated with LiCl of increasing dosages. In addition, reverse transcription-PCR (RT-PCR and Western-blot were conducted to measure the expression of Six2 and some maker genes of Wnt and bone-morphogenetic-protein (BMP signaling pathway. Furthermore, luciferase assay was also carried out to detect the transcriptional regulation of Six2. Then we found LiCl promoted MM cell proliferation at low-concentration (10, 20, 30, and 40 mM. The expression of Six2 was dose-dependently increased in low-concentration (10, 20, 30, and 40 mM at both mRNA and protein level. In addition, both of cell proliferation and Six2 expression in MM cells declined when dosage reached high-concentration (50 mM. However, Six2 knock-down converted the proliferation reduction at 50 mM. Furthermore, Six2 deficiency increased the apoptosis of MM cells, compared with negative control cells at relative LiCl concentration. However, the abnormal rise of apoptosis at 30 mM of LiCl concentration implies that it might be the reduction of GSK3β that increased cell apoptosis. Together, these demonstrate that LiCl can induce the proliferation and apoptosis of MM cells coordinating with Six2.

  18. Cellular senescence and organismal aging.

    Science.gov (United States)

    Jeyapalan, Jessie C; Sedivy, John M

    2008-01-01

    Cellular senescence, first observed and defined using in vitro cell culture studies, is an irreversible cell cycle arrest which can be triggered by a variety of factors. Emerging evidence suggests that cellular senescence acts as an in vivo tumor suppression mechanism by limiting aberrant proliferation. It has also been postulated that cellular senescence can occur independently of cancer and contribute to the physiological processes of normal organismal aging. Recent data have demonstrated the in vivo accumulation of senescent cells with advancing age. Some characteristics of senescent cells, such as the ability to modify their extracellular environment, could play a role in aging and age-related pathology. In this review, we examine current evidence that links cellular senescence and organismal aging.

  19. 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 ...

  20. Characterization of the loss of SUMO pathway function on cancer cells and tumor proliferation.

    Directory of Open Access Journals (Sweden)

    Xingyue He

    Full Text Available SUMOylation is a post-translational ubiquitin-like protein modification pathway that regulates important cellular processes including chromosome structure, kinetochore function, chromosome segregation, nuclear and sub-nuclear organization, transcription and DNA damage repair. There is increasing evidence that the SUMO pathway is dysregulated in cancer, raising the possibility that modulation of this pathway may have therapeutic potential. To investigate the importance of the SUMO pathway in the context of cancer cell proliferation and tumor growth, we applied lentivirus-based short hairpin RNAs (shRNA to knockdown SUMO pathway genes in human cancer cells. shRNAs for SAE2 and UBC9 reduced SUMO conjugation activity and inhibited proliferation of human cancer cells. To expand upon these observations, we generated doxycycline inducible conditional shRNA cell lines for SAE2 to achieve acute and reversible SAE2 knockdown. Conditional SAE2 knockdown in U2OS and HCT116 cells slowed cell growth in vitro, and SAE2 knockdown induced multiple terminal outcomes including apoptosis, endoreduplication and senescence. Multinucleated cells became senescent and stained positive for the senescence marker, SA-β Gal, and displayed elevated levels of p53 and p21. In an attempt to explain these phenotypes, we confirmed that loss of SUMO pathway activity leads to a loss of SUMOylated Topoisomerase IIα and the appearance of chromatin bridges which can impair proper cytokinesis and lead to multinucleation. Furthermore, knockdown of SAE2 induces disruption of PML nuclear bodies which may further promote apoptosis or senescence. In an in vivo HCT116 xenograft tumor model, conditional SAE2 knockdown strongly impaired tumor growth. These data demonstrate that the SUMO pathway is required for cancer cell proliferation in vitro and tumor growth in vivo, implicating the SUMO pathway as a potential cancer therapeutic target.

  1. Proteomic analysis reveals a role for Bcl2-associated athanogene 3 and major vault protein in resistance to apoptosis in senescent cells by regulating ERK1/2 activation.

    Science.gov (United States)

    Pasillas, Martina P; Shields, Sarah; Reilly, Rebecca; Strnadel, Jan; Behl, Christian; Park, Robin; Yates, John R; Klemke, Richard; Gonias, Steven L; Coppinger, Judith A

    2015-01-01

    Senescence is a prominent solid tumor response to therapy in which cells avoid apoptosis and instead enter into prolonged cell cycle arrest. We applied a quantitative proteomics screen to identify signals that lead to therapy-induced senescence and discovered that Bcl2-associated athanogene 3 (Bag3) is up-regulated after adriamycin treatment in MCF7 cells. Bag3 is a member of the BAG family of co-chaperones that interacts with Hsp70. Bag3 also regulates major cell-signaling pathways. Mass spectrometry analysis of the Bag3 Complex revealed a novel interaction between Bag3 and Major Vault Protein (MVP). Silencing of Bag3 or MVP shifts the cellular response to adriamycin to favor apoptosis. We demonstrate that Bag3 and MVP contribute to apoptosis resistance in therapy-induced senescence by increasing the level of activation of extracellular signal-regulated kinase1/2 (ERK1/2). Silencing of either Bag3 or MVP decreased ERK1/2 activation and promoted apoptosis in adriamycin-treated cells. An increase in nuclear accumulation of MVP is observed during therapy-induced senescence and the shift in MVP subcellular localization is Bag3-dependent. We propose a model in which Bag3 binds to MVP and facilitates MVP accumulation in the nucleus, which sustains ERK1/2 activation. We confirmed that silencing of Bag3 or MVP shifts the response toward apoptosis and regulates ERK1/2 activation in a panel of diverse breast cancer cell lines. This study highlights Bag3-MVP as an important complex that regulates a potent prosurvival signaling pathway and contributes to chemotherapy resistance in breast cancer. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  2. Long noncoding RNA PANDA and scaffold-attachment-factor SAFA control senescence entry and exit.

    Science.gov (United States)

    Puvvula, Pavan Kumar; Desetty, Rohini Devi; Pineau, Pascal; Marchio, Agnés; Moon, Anne; Dejean, Anne; Bischof, Oliver

    2014-11-19

    Cellular senescence is a stable cell cycle arrest that limits the proliferation of pre-cancerous cells. Here we demonstrate that scaffold-attachment-factor A (SAFA) and the long noncoding RNA PANDA differentially interact with polycomb repressive complexes (PRC1 and PRC2) and the transcription factor NF-YA to either promote or suppress senescence. In proliferating cells, SAFA and PANDA recruit PRC complexes to repress the transcription of senescence-promoting genes. Conversely, the loss of SAFA-PANDA-PRC interactions allows expression of the senescence programme. Accordingly, we find that depleting either SAFA or PANDA in proliferating cells induces senescence. However, in senescent cells where PANDA sequesters transcription factor NF-YA and limits the expression of NF-YA-E2F-coregulated proliferation-promoting genes, PANDA depletion leads to an exit from senescence. Together, our results demonstrate that PANDA confines cells to their existing proliferative state and that modulating its level of expression can cause entry or exit from senescence.

  3. Study of radionuclide 90Sr-90Y on cell proliferation and apoptosis in benign prostatic hyperplasia

    International Nuclear Information System (INIS)

    Zhang Tong; Wei Wei; Zou Benjie; Liu Fang; Xu Zhishun

    2003-01-01

    Objective: To investigate the effect of 90 Sr- 90 Yon cell proliferation and apoptosis in benign prostatic hyperplasia. Methods: The apoptosis and expression of Ki-67 in benign prostatic hyperplasia (BPH) before and after irradiation 90 Sr- 90 Y were detected by transferase-mediated dUTP-biotin nick end labeling (TUNEL) method and immunohistochemical technique, respectively. Results: The proliferation index (PI) of BPH after 90 Sr- 90 Y irradiation was much lower than that before irradiation, but there was no significant change in apoptosis index (AI). Conclusion: Irradiation with 90 Sr- 90 Y could restrain cell proliferation of BPH, but could not induce apoptosis

  4. Senescent mouse cells fail to overtly regulate the HIRA histone chaperone and do not form robust Senescence Associated Heterochromatin Foci

    Directory of Open Access Journals (Sweden)

    Enders Greg H

    2010-06-01

    Full Text Available Abstract Background Cellular senescence is a permanent growth arrest that occurs in response to cellular stressors, such as telomere shortening or activation of oncogenes. Although the process of senescence growth arrest is somewhat conserved between mouse and human cells, there are some critical differences in the molecular pathways of senescence between these two species. Recent studies in human fibroblasts have defined a cell signaling pathway that is initiated by repression of a specific Wnt ligand, Wnt2. This, in turn, activates a histone chaperone HIRA, and culminates in formation of specialized punctate domains of facultative heterochromatin, called Senescence-Associated Heterochromatin Foci (SAHF, that are enriched in the histone variant, macroH2A. SAHF are thought to repress expression of proliferation-promoting genes, thereby contributing to senescence-associated proliferation arrest. We asked whether this Wnt2-HIRA-SAHF pathway is conserved in mouse fibroblasts. Results We show that mouse embryo fibroblasts (MEFs and mouse skin fibroblasts, do not form robust punctate SAHF in response to an activated Ras oncogene or shortened telomeres. However, senescent MEFs do exhibit elevated levels of macroH2A staining throughout the nucleus as a whole. Consistent with their failure to fully activate the SAHF assembly pathway, the Wnt2-HIRA signaling axis is not overtly regulated between proliferating and senescent mouse cells. Conclusions In addition to the previously defined differences between mouse and human cells in the mechanisms and phenotypes associated with senescence, we conclude that senescent mouse and human fibroblasts also differ at the level of chromatin and the signaling pathways used to regulate chromatin. These differences between human and mouse senescence may contribute to the increased propensity of mouse fibroblasts (and perhaps other mouse cell types to become immortalized and transformed, compared to human cells.

  5. ATM-deficient human fibroblast cells are resistant to low levels of DNA double-strand break induced apoptosis and subsequently undergo drug-induced premature senescence

    International Nuclear Information System (INIS)

    Park, Jun; Jo, Yong Hwa; Cho, Chang Hoon; Choe, Wonchae; Kang, Insug; Baik, Hyung Hwan; Yoon, Kyung-Sik

    2013-01-01

    Highlights: ► A-T cells were not hypersensitive to low levels of DNA DSBs. ► A-T cells have enhanced Akt but defect in activation of p53 and apoptotic proteins. ► A-T cells underwent premature senescence after DNA damage accumulated. ► Chemotherapeutic effect in cancer therapy may be associated with premature senescence. -- Abstract: DNA DSBs are induced by IR or radiomimetic drugs such as doxorubicin. It has been indicated that cells from ataxia-telangiectasia patients are highly sensitive to radiation due to defects in DNA repair, but whether they have impairment in apoptosis has not been fully elucidated. A-T cells showed increased sensitivity to high levels of DNA damage, however, they were more resistant to low doses. Normal cells treated with combination of KU55933, a specific ATM kinase inhibitor, and doxorubicin showed increased resistance as they do in a similar manner to A-T cells. A-T cells have higher viability but more DNA breaks, in addition, the activations of p53 and apoptotic proteins (Bax and caspase-3) were deficient, but Akt expression was enhanced. A-T cells subsequently underwent premature senescence after treatment with a low dose of doxorubicin, which was confirmed by G2 accumulation, senescent morphology, and SA-β-gal positive until 15 days repair incubation. Finally, A-T cells are radio-resistant at low doses due to its defectiveness in detecting DNA damage and apoptosis, but the accumulation of DNA damage leads cells to premature senescence.

  6. MYC through miR-17-92 Suppresses Specific Target Genes to Maintain Survival, Autonomous Proliferation, and a Neoplastic State

    KAUST Repository

    Li, Yulin; Choi, Peter  S.; Casey, Stephanie  C.; Dill, David  L.; Felsher, Dean  W.

    2014-01-01

    The MYC oncogene regulates gene expression through multiple mechanisms, and its overexpression culminates in tumorigenesis. MYC inactivation reverses turmorigenesis through the loss of distinguishing features of cancer, including autonomous proliferation and survival. Here we report that MYC via miR-17-92 maintains a neoplastic state through the suppression of chromatin regulatory genes Sin3b, Hbp1, Suv420h1, and Btg1, as well as the apoptosis regulator Bim. The enforced expression of miR-17-92 prevents MYC suppression from inducing proliferative arrest, senescence, and apoptosis and abrogates sustained tumor regression. Knockdown of the five miR-17-92 target genes blocks senescence and apoptosis while it modestly delays proliferative arrest, thus partially recapitulating miR-17-92 function. We conclude that MYC, via miR-17-92, maintains a neoplastic state by suppressing specific target genes.

  7. MYC through miR-17-92 Suppresses Specific Target Genes to Maintain Survival, Autonomous Proliferation, and a Neoplastic State

    KAUST Repository

    Li, Yulin

    2014-08-01

    The MYC oncogene regulates gene expression through multiple mechanisms, and its overexpression culminates in tumorigenesis. MYC inactivation reverses turmorigenesis through the loss of distinguishing features of cancer, including autonomous proliferation and survival. Here we report that MYC via miR-17-92 maintains a neoplastic state through the suppression of chromatin regulatory genes Sin3b, Hbp1, Suv420h1, and Btg1, as well as the apoptosis regulator Bim. The enforced expression of miR-17-92 prevents MYC suppression from inducing proliferative arrest, senescence, and apoptosis and abrogates sustained tumor regression. Knockdown of the five miR-17-92 target genes blocks senescence and apoptosis while it modestly delays proliferative arrest, thus partially recapitulating miR-17-92 function. We conclude that MYC, via miR-17-92, maintains a neoplastic state by suppressing specific target genes.

  8. Histone deacetylase inhibitor valproic acid promotes the induction of pluripotency in mouse fibroblasts by suppressing reprogramming-induced senescence stress

    Energy Technology Data Exchange (ETDEWEB)

    Zhai, Yingying; Chen, Xi; Yu, Dehai [Stem Cell and Cancer Center, First Affiliated Hospital, Jilin University, Changchun, Jilin 130061 (China); Stanford University Medical School, Palo Alto Veterans Institute for Research, Palo Alto, CA 94304 (United States); Li, Tao [Stanford University Medical School, Palo Alto Veterans Institute for Research, Palo Alto, CA 94304 (United States); Cui, Jiuwei; Wang, Guanjun [Stem Cell and Cancer Center, First Affiliated Hospital, Jilin University, Changchun, Jilin 130061 (China); Hu, Ji-Fan, E-mail: jifan@stanford.edu [Stem Cell and Cancer Center, First Affiliated Hospital, Jilin University, Changchun, Jilin 130061 (China); Stanford University Medical School, Palo Alto Veterans Institute for Research, Palo Alto, CA 94304 (United States); Li, Wei, E-mail: jdyylw@163.com [Stem Cell and Cancer Center, First Affiliated Hospital, Jilin University, Changchun, Jilin 130061 (China)

    2015-09-10

    Histone deacetylase inhibitor valproic acid (VPA) has been used to increase the reprogramming efficiency of induced pluripotent stem cell (iPSC) from somatic cells, yet the specific molecular mechanisms underlying this effect is unknown. Here, we demonstrate that reprogramming with lentiviruses carrying the iPSC-inducing factors (Oct4-Sox2-Klf4-cMyc, OSKM) caused senescence in mouse fibroblasts, establishing a stress barrier for cell reprogramming. Administration of VPA protected cells from reprogramming-induced senescent stress. Using an in vitro pre-mature senescence model, we found that VPA treatment increased cell proliferation and inhibited apoptosis through the suppression of the p16/p21 pathway. In addition, VPA also inhibited the G2/M phase blockage derived from the senescence stress. These findings highlight the role of VPA in breaking the cell senescence barrier required for the induction of pluripotency. - Highlights: • Histone deacetylase inhibitor valproic acid enhances iPSC induction. • Valproic acid suppresses reprogramming-induced senescence stress. • Valproic acid downregulates the p16/p21 pathway in reprogramming. • This study demonstrates a new mechanistic role of valproic acid in enhancing reprogramming.

  9. Enhanced NOLC1 promotes cell senescence and represses hepatocellular carcinoma cell proliferation by disturbing the organization of nucleolus.

    Science.gov (United States)

    Yuan, Fuwen; Zhang, Yu; Ma, Liwei; Cheng, Qian; Li, Guodong; Tong, Tanjun

    2017-08-01

    The nucleolus is a key organelle that is responsible for the synthesis of rRNA and assembly of ribosomal subunits, which is also the center of metabolic control because of the critical role of ribosomes in protein synthesis. Perturbations of rRNA biogenesis are closely related to cell senescence and tumor progression; however, the underlying molecular mechanisms are not well understood. Here, we report that cellular senescence-inhibited gene (CSIG) knockdown up-regulated NOLC1 by stabilizing the 5'UTR of NOLC1 mRNA, and elevated NOLC1 induced the retention of NOG1 in the nucleolus, which is responsible for rRNA processing. Besides, the expression of NOLC1 was negatively correlated with CSIG in the aged mouse tissue and replicative senescent 2BS cells, and the down-regulation of NOLC1 could rescue CSIG knockdown-induced 2BS senescence. Additionally, NOLC1 expression was decreased in human hepatocellular carcinoma (HCC) tissue, and the ectopic expression of NOLC1 repressed the proliferation of HCC cells and tumor growth in a HCC xenograft model. © 2017 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

  10. RODENT AND HUMAN NEUROPROGENITOR CELLS FOR HIGH-CONTENT SCREENS OF CHEMICAL EFFECTS ON PROLIFERATION AND APOPTOSIS

    Science.gov (United States)

    The objective of these experiments is to develop high-throughput screens for proliferation and apoptosis in order to compare rodent and human neuroprogenitor cell responses to potential developmental neurotoxicants. Effects of 4 chemicals on proliferation and apoptosis in mouse c...

  11. Paris polyphylla extract inhibits proliferation and promotes apoptosis ...

    African Journals Online (AJOL)

    Purpose: To investigate the effect of Paris polyphylla extract (PPE) on proliferation and apoptosis in A549 human lung cancer cells. Methods: Morphological changes were examined by microscopy in A549 cells after exposure to PPE. Trypan blue staining of living cells was used to aid the construction of the cell growth curve ...

  12. Inhibition of Mitochondrial Cytochrome c Release and Suppression of Caspases by Gamma-Tocotrienol Prevent Apoptosis and Delay Aging in Stress-Induced Premature Senescence of Skin Fibroblasts

    Directory of Open Access Journals (Sweden)

    Suzana Makpol

    2012-01-01

    Full Text Available In this study, we determined the molecular mechanism of γ-tocotrienol (GTT in preventing cellular aging by focusing on its anti-apoptotic effect in stress-induced premature senescence (SIPS model of human diploid fibroblasts (HDFs. Results obtained showed that SIPS exhibited senescent-phenotypic characteristic, increased expression of senescence-associated β-galactosidase (SA β-gal and promoted G0/G1 cell cycle arrest accompanied by shortening of telomere length with decreased telomerase activity. Both SIPS and senescent HDFs shared similar apoptotic changes such as increased Annexin V-FITC positive cells, increased cytochrome c release and increased activation of caspase-9 and caspase-3 (P<0.05. GTT treatment resulted in a significant reduction of Annexin V-FITC positive cells, inhibited cytochrome c release and decreased activation of caspase-9 and caspase-3 (P<0.05. Gene expression analysis showed that GTT treatment down regulated BAX mRNA, up-regulated BCL2A1 mRNA and decreased the ratio of Bax/Bcl-2 protein expression (P<0.05 in SIPS. These findings suggested that GTT inhibits apoptosis by modulating the upstream apoptosis cascade, causing the inhibition of cytochrome c release from the mitochondria with concomitant suppression of caspase-9 and caspase-3 activation. In conclusion, GTT delays cellular senescence of human diploid fibroblasts through the inhibition of intrinsic mitochondria-mediated pathway which involved the regulation of pro- and anti-apoptotic genes and proteins.

  13. Cell proliferation and apoptosis in rat mammary glands following combinational exposure to bisphenol A and genistein

    International Nuclear Information System (INIS)

    Wang, Jun; Jenkins, Sarah; Lamartiniere, Coral A

    2014-01-01

    Humans are exposed to an array of both harmful and beneficial hormonally active compounds in the environment and through diet. Two such chemicals are Bisphenol A (BPA), a plasticizer, and genistein, a component of soy. Prepubertal exposure to BPA increased mammary carcinogenesis, while genistein suppressed cancer in a chemically-induced model of rodent mammary cancer. The purpose of this research was to determine the effects of combinational exposure to genistein and BPA on cell proliferation, apoptosis, and associated proteins as markers of cancer in mammary glands of rats exposed prepubertally to these environmental chemicals. Prepubertal rats (postpartum days (PND) 2–20) were exposed through lactation via nursing dams treated orally with sesame oil (SO), BPA, genistein, or a combination of BPA and genistein (BPA + Gen). Cell proliferation, apoptosis and protein expressions were investigated for mechanistic studies in mammary glands of rats exposed to these environmental chemicals. Prepubertal exposure to genistein increased cell proliferation in mammary glands of PND21 rats, while BPA increased cell proliferation in adult (PND50) rats. Prepubertal combinational exposure to BPA + Gen increased cell proliferation and reduced apoptosis in PND21 rats, but reduced cell proliferation and increased apoptosis in PND50 rats. The altered mechanisms behind these cellular responses appear to be centered on differential protein expression of caspases, PARP, Bad, p21, Akts, PTEN, ER-β and SRCs 1–3, in the rat mammary gland. Prepubertal BPA exposure resulted in increased cell proliferation in mammary glands of PND50 rats, a process associated with increased risk of cancer development in a chemically-induced mammary cancer. On the other hand, genistein stimulated cell proliferation at PND21, a process that correlates with mammary gland maturation and chemoprevention. In contrast to single chemical exposure, combinational exposure to BPA + Gen performed most similarly to

  14. Differential effects of culture senescence and mechanical stimulation on the proliferation and leiomyogenic differentiation of MSC from different sources: implications for engineering vascular grafts.

    Science.gov (United States)

    Koobatian, Maxwell T; Liang, Mao-Shih; Swartz, Daniel D; Andreadis, Stelios T

    2015-04-01

    We examined the effects of senescence on the proliferation and leiomyogenic differentiation potential of mesenchymal stem cells (MSCs) isolated from bone marrow (BM-MSCs) or hair follicles (HF-MSCs). To this end, we compared ovine HF-MSCs and BM-MSCs in terms of their proliferation and differentiation potential to the smooth muscle cell lineage. We discovered that HF-MSCs are less susceptible to culture senescence compared with BM-MSCs. We hypothesized that application of mechanical forces may enhance the contractility and mechanical properties of vascular constructs prepared from senescent MSCs. Interestingly, HF-MSCs and BM-MSCs responded differently to changes in the mechanical microenvironment, suggesting that despite phenotypic similarities, MSCs from different anatomic locations may activate different pathways in response to the same microenvironmental factors. In turn, this may also suggest that cell-based tissue regeneration approaches may need to be tailored to the stem cell origin, donor age, and culture time for optimal results.

  15. 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.

  16. 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

  17. Evaluation of cell proliferation and apoptosis in placentas of rats with severe diabetes

    Directory of Open Access Journals (Sweden)

    Marilza Vieira Cunha Rudge

    2012-04-01

    Full Text Available The aim of this work was to analyze the cell proliferation and apoptosis indexes on the 18th and 21st days of pregnancy of diabetic rats and to correlate with maternal glycemia and perinatal outcomes. Placentas from 20 Wistar rats were collected and divided into four experimental groups: control and diabetic of 18 and 21 days of pregnancy. The cell proliferation was analyzed using the PCNA expression and apoptosis by the TUNEL method. It was observed that PCNA and TUNEL indexes decreased from day 18 to 21 of pregnancy in the placentas of diabetic rats and these values were lower than control groups. Diabetic dams presented higher percentage of small for pregnancy age (SPA fetuses. However, there was no difference between the PCNA and TUNEL indexes in SPA and N-SPA fetuses in all the groups and these indexes were not correlated to maternal glycemic. Thus, placental cell proliferation and apoptosis did not interfere in the intrauterine growth restriction.

  18. Piper betle L. Modulates Senescence-Associated Genes Expression in Replicative Senescent Human Diploid Fibroblasts

    Directory of Open Access Journals (Sweden)

    Lina Wati Durani

    2017-01-01

    Full Text Available Piper betle (PB is a traditional medicine that is widely used to treat different diseases around Asian region. The leaf extracts contain various bioactive compounds, which were reported to have antidiabetic, antibacterial, anti-inflammatory, antioxidant, and anticancer effects. In this study, the effect of PB aqueous extracts on replicative senescent human diploid fibroblasts (HDFs was investigated by determining the expressions of senescence-associated genes using quantitative PCR. Our results showed that PB extracts at 0.4 mg/ml can improve cell proliferation of young (143%, presenescent (127.3%, and senescent (157.3% HDFs. Increased expressions of PRDX6, TP53, CDKN2A, PAK2, and MAPK14 were observed in senescent HDFs compared to young and/or presenescent HDFs. Treatment with PB extracts modulates the transcriptional profile changes in senescent HDFs. By contrast, expressions of SOD1 increased, whereas GPX1, PRDX6, TP53, CDKN2A, PAK2, and MAPK14 were decreased in PB-treated senescent HDFs compared to untreated senescent HDFs. In conclusion, this study indicates the modulation of PB extracts on senescence-associated genes expression of replicative senescent HDFs. Further studies warrant determining the mechanism of PB in modulating replicative senescence of HDFs through these signaling pathways.

  19. Piper betle L. Modulates Senescence-Associated Genes Expression in Replicative Senescent Human Diploid Fibroblasts.

    Science.gov (United States)

    Durani, Lina Wati; Khor, Shy Cian; Tan, Jen Kit; Chua, Kien Hui; Mohd Yusof, Yasmin Anum; Makpol, Suzana

    2017-01-01

    Piper betle (PB) is a traditional medicine that is widely used to treat different diseases around Asian region. The leaf extracts contain various bioactive compounds, which were reported to have antidiabetic, antibacterial, anti-inflammatory, antioxidant, and anticancer effects. In this study, the effect of PB aqueous extracts on replicative senescent human diploid fibroblasts (HDFs) was investigated by determining the expressions of senescence-associated genes using quantitative PCR. Our results showed that PB extracts at 0.4 mg/ml can improve cell proliferation of young (143%), presenescent (127.3%), and senescent (157.3%) HDFs. Increased expressions of PRDX6 , TP53 , CDKN2A , PAK2 , and MAPK14 were observed in senescent HDFs compared to young and/or presenescent HDFs. Treatment with PB extracts modulates the transcriptional profile changes in senescent HDFs. By contrast, expressions of SOD1 increased, whereas GPX1 , PRDX6 , TP53 , CDKN2A , PAK2 , and MAPK14 were decreased in PB-treated senescent HDFs compared to untreated senescent HDFs. In conclusion, this study indicates the modulation of PB extracts on senescence-associated genes expression of replicative senescent HDFs. Further studies warrant determining the mechanism of PB in modulating replicative senescence of HDFs through these signaling pathways.

  20. Mechanisms and kinetics of proliferation and fibrosis development in a mouse model of thyrocyte hyperplasia.

    Science.gov (United States)

    Ciornei, Radu Tudor; Hong, So-Hee; Fang, Yujiang; Zhu, Ziwen; Braley-Mullen, Helen

    2016-01-01

    IFN-γ(-/-) NOD.H-2h4 mice develop autoimmune disease with extensive hyperplasia and proliferation of thyroid epithelial cells (TEC H/P) and fibrosis. Splenic T cells from donors with severe TEC H/P transfer TEC H/P to SCID recipients. The goal of this study was to determine what factors control TEC H/P development/progression by examining T cells, markers of apoptosis, senescence and proliferation in thyroids of SCID recipients over time. At 28days, T cell infiltration was maximal, thyrocytes were proliferating, and fibrosis was moderate. At days 60 and 90, thyroids were larger with more fibrosis. T cells, cytokines and thyrocyte proliferation decreased, and cell cycle inhibitor proteins, and anti-apoptotic molecules increased. T cells and thyrocytes had foci of phosphorylated histone protein H2A.X, indicative of cellular senescence, when TEC H/P progressed and thyrocyte proliferation declined. Some thyrocytes were regenerating at day 90, with irregularly shaped empty follicles and ciliated epithelium. Proliferating thyrocytes were thyroid transcription factor (TTF1)-positive, suggesting they derived from epithelial cells and not brachial cleft remnants. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. The effect of yucca on proliferation, apoptosis, and steroidogenesis of porcine ovarian granulosa cells

    Directory of Open Access Journals (Sweden)

    Aneta Štochmaľová

    2014-02-01

    Full Text Available Yucca shidigera is a medicinal plant native to Mexico. Is a plant widely used in folk medicine to treat a variety of ailmentary disorders, but its action on reproductive processes and possible mechanisms of such action remains unknown. Yucca schidigera extract contains a number of steroidal saponins that, because of their biological activity, have attracted attention from the food industry for many years. Yucca extract is used as a natural feed additive with positive effect to microflora, digestion, metabolism and to improve animal muscle growth. Its extract has been used as a foodstuff and folk medicine to treat a wide variety of diseases for many years. Nevertheless, it remaines unknown, whether consumption of yucca can affect reproductive system. The aim of this study was to examine the effects of yucca on basic ovarian cell functions - proliferation, apoptosis and steroidogenesis. Porcine ovarian granulosa cells were cultured with and without yucca extract (added at doses 0; 1; 10 and 100 μg.mL-1 of medium. Markers of proliferation (% of PCNA-positive cells and apoptosis (% cells containing bax were analysed by immunocytochemistry. Release of steroid hormones (progesterone and testosterone was measured by EIA. It was observed, that addition of yucca inhibited proliferation (expression of PCNA, increased apoptosis (expression of bax, stimulated progesterone and inhibited testosterone release. The ability of yucca to reduce ovarian cell proliferation, to promote ovarian cell apoptosis and affect steroidogenesis demonstrates the direct influence of yucca on female gonads. Furthermore, our observations suggest the multiple sites of action (proliferation, apoptosis, steroidogenesis of yucca on porcine ovarian cell functions. It is not to be excluded, that consumption of yucca can suppress female reproductive functions.

  2. Orlistat Reduces Proliferation and Enhances Apoptosis in Human Pancreatic Cancer Cells (PANC-1).

    Science.gov (United States)

    Sokolowska, Ewa; Presler, Malgorzata; Goyke, Elzbieta; Milczarek, Ryszard; Swierczynski, Julian; Sledzinski, Tomasz

    2017-11-01

    Pancreatic cancer is a disease with very poor prognosis, and none of currently available pharmacotherapies have proven to be efficient in this indication. The aim of this study was to analyze the expression of fatty acid synthase (FASN) gene as a potential therapeutic target in proliferating human pancreatic cancer cells (PANC-1), and verify if orlistat, originally developed as an anti-obesity drug, inhibits PANC-1 proliferation. The effects of orlistat on gene expression, lipogenesis, proliferation and apoptosis was studied in PANC-1 cell culture. Expression of FASN increased during proliferation of PANC-1. Inhibition of FASN by orlistat resulted in a significant reduction of PANC-1 proliferation and enhanced apoptosis of these cells. This study showed, to our knowledge for the first time, that orlistat exhibits significant antitumor activity against PANC-1 cells. This implies that orlistat analogs with good oral bioavailability may find application in pharmacotherapy of pancreatic cancer. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  3. Accelerated cellular senescence phenotype of GAPDH-depleted human lung carcinoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Phadke, Manali; Krynetskaia, Natalia [Temple University School of Pharmacy, Philadelphia, PA 19140 (United States); Mishra, Anurag [Jayne Haines Center for Pharmacogenomics, Temple University School of Pharmacy, Philadelphia, PA 19140 (United States); Krynetskiy, Evgeny, E-mail: ekrynets@temple.edu [Temple University School of Pharmacy, Philadelphia, PA 19140 (United States); Jayne Haines Center for Pharmacogenomics, Temple University School of Pharmacy, Philadelphia, PA 19140 (United States)

    2011-07-29

    Highlights: {yields} We examined the effect of glyceraldehyde 3-phosphate (GAPDH) depletion on proliferation of human carcinoma A549 cells. {yields} GAPDH depletion induces accelerated senescence in tumor cells via AMPK network, in the absence of DNA damage. {yields} Metabolic and genetic rescue experiments indicate that GAPDH has regulatory functions linking energy metabolism and cell cycle. {yields} Induction of senescence in LKB1-deficient lung cancer cells via GAPDH depletion suggests a novel strategy to control tumor cell proliferation. -- Abstract: Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) is a pivotal glycolytic enzyme, and a signaling molecule which acts at the interface between stress factors and the cellular apoptotic machinery. Earlier, we found that knockdown of GAPDH in human carcinoma cell lines resulted in cell proliferation arrest and chemoresistance to S phase-specific cytotoxic agents. To elucidate the mechanism by which GAPDH depletion arrests cell proliferation, we examined the effect of GAPDH knockdown on human carcinoma cells A549. Our results show that GAPDH-depleted cells establish senescence phenotype, as revealed by proliferation arrest, changes in morphology, SA-{beta}-galactosidase staining, and more than 2-fold up-regulation of senescence-associated genes DEC1 and GLB1. Accelerated senescence following GAPDH depletion results from compromised glycolysis and energy crisis leading to the sustained AMPK activation via phosphorylation of {alpha} subunit at Thr172. Our findings demonstrate that GAPDH depletion switches human tumor cells to senescent phenotype via AMPK network, in the absence of DNA damage. Rescue experiments using metabolic and genetic models confirmed that GAPDH has important regulatory functions linking the energy metabolism and the cell cycle networks. Induction of senescence in LKB1-deficient non-small cell lung cancer cells via GAPDH depletion suggests a novel strategy to control tumor cell proliferation.

  4. 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.

  5. 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.

  6. Sepsis reveals compartment-specific responses in intestinal proliferation and apoptosis in transgenic mice whose enterocytes re-enter the cell cycle.

    Science.gov (United States)

    Lyons, John D; Klingensmith, Nathan J; Otani, Shunsuke; Mittal, Rohit; Liang, Zhe; Ford, Mandy L; Coopersmith, Craig M

    2017-12-01

    Cell production and death are tightly regulated in the rapidly renewing gut epithelium, with proliferation confined to crypts and apoptosis occurring in villi and crypts. This study sought to determine how stress alters these compartmentalized processes. Wild-type mice made septic via cecal ligation and puncture had decreased crypt proliferation and increased crypt and villus apoptosis. Fabpi -TAg mice expressing large T-antigen solely in villi had ectopic enterocyte proliferation with increased villus apoptosis in unmanipulated animals. Septic fabpi -TAg mice had an unexpected increase in villus proliferation compared with unmanipulated littermates, whereas crypt proliferation was decreased. Cell cycle regulators cyclin D1 and cyclin D2 were decreased in jejunal tissue in septic transgenic mice. In contrast, villus and crypt apoptosis were increased in septic fabpi -TAg mice. To examine the relationship between apoptosis and proliferation in a compartment-specific manner, fabpi -TAg mice were crossed with fabpl -Bcl-2 mice, resulting in expression of both genes in the villus but Bcl-2 alone in the crypt. Septic bi-transgenic animals had decreased crypt apoptosis but had a paradoxical increase in villus apoptosis compared with septic fabpi -TAg mice, associated with decreased proliferation in both compartments. Thus, sepsis unmasks compartment-specific proliferative and apoptotic regulation that is not present under homeostatic conditions.-Lyons, J. D., Klingensmith, N. J., Otani, S., Mittal, R., Liang, Z., Ford, M. L., Coopersmith, C. M. Sepsis reveals compartment-specific responses in intestinal proliferation and apoptosis in transgenic mice whose enterocytes re-enter the cell cycle. © FASEB.

  7. 20(S-ginsenoside Rg3 promotes senescence and apoptosis in gallbladder cancer cells via the p53 pathway

    Directory of Open Access Journals (Sweden)

    Zhang F

    2015-08-01

    Full Text Available Fei Zhang,* Maolan Li,* Xiangsong Wu,* Yunping Hu, Yang Cao, Xu’an Wang, Shanshan Xiang, Huaifeng Li, Lin Jiang, Zhujun Tan, Wei Lu, Hao Weng, Yijun Shu, Wei Gong, Xuefeng Wang, Yong Zhang, Weibin Shi, Ping Dong,# Jun Gu,# Yingbin Liu#Department of General Surgery and Laboratory of General Surgery, Xinhua Hospital Affiliated to Shanghai Jiao Tong University, School of Medicine, Institute of Biliary Tract Disease, Shanghai Jiao Tong University School of Medicine, Shanghai, People’s Republic of China *These authors contributed equally to this work #These authors jointly directed this work Abstract: Gallbladder cancer (GBC, the most frequent malignancy of the biliary tract, is associated with high mortality and extremely poor prognosis. 20(S-ginsenoside Rg3 (20(S-Rg3 is a steroidal saponin with high pharmacological activity. However, the anticancer effect of 20(S-Rg3 in human GBC has not yet been determined. In this study, we primarily found that 20(S-Rg3 exposure suppressed the survival of both NOZ and GBC-SD cell lines in a concentration-dependent manner. Moreover, induction of cellular senescence and G0/G1 arrest by 20(S-Rg3 were accompanied by a large accumulation of p53 and p21 as a result of murine double minute 2 (MDM2 inhibition. 20(S-Rg3 also caused a remarkable increase in apoptosis via the activation of the mitochondrial-mediated intrinsic caspase pathway. Furthermore, intraperitoneal injection of 20(S-Rg3 (20 or 40 mg/kg for 3 weeks markedly inhibited the growth of xenografts in nude mice. Our results demonstrated that 20(S-Rg3 potently inhibited growth and survival of GBC cells both in vitro and in vivo. 20(S-Rg3 attenuated GBC growth probably via activation of the p53 pathway, and subsequent induction of cellular senescence and mitochondrial-dependent apoptosis. Therefore, 20(S-Rg3 may be a potential chemotherapeutic agent for GBC therapy.Keywords: gallbladder cancer, 20(S-ginsenoside Rg3, senescence, apoptosis, p53 pathway

  8. Senescence induction; a possible cancer therapy

    Directory of Open Access Journals (Sweden)

    Kondoh Hiroshi

    2009-01-01

    Full Text Available Abstract Cellular immortalization is a crucial step during the development of human cancer. Primary mammalian cells reach replicative exhaustion after several passages in vitro, a process called replicative senescence. During such a state of permanent growth arrest, senescent cells are refractory to physiological proliferation stimuli: they have altered cell morphology and gene expression patterns, although they remain viable with preserved metabolic activity. Interestingly, senescent cells have also been detected in vivo in human tumors, particularly in benign lesions. Senescence is a mechanism that limits cellular lifespan and constitutes a barrier against cellular immortalization. During immortalization, cells acquire genetic alterations that override senescence. Tumor suppressor genes and oncogenes are closely involved in senescence, as their knockdown and ectopic expression confer immortality and senescence induction, respectively. By using high throughput genetic screening to search for genes involved in senescence, several candidate oncogenes and putative tumor suppressor genes have been recently isolated, including subtypes of micro-RNAs. These findings offer new perspectives in the modulation of senescence and open new approaches for cancer therapy.

  9. 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

  10. Gemcitabine inhibits proliferation and induces apoptosis in human pancreatic cancer PANC-1 cells.

    Science.gov (United States)

    Yong-Xian, Gui; Xiao-Huan, Li; Fan, Zhang; Guo-Fang, Tian

    2016-10-01

    The aim of the study is to investigate the underlying molecular mechanisms by which gemcitabine (gem) inhibits proliferation and induces apoptosis in human pancreatic cancer PANC-1 cells in vitro. After PANC-1 cells had been treated by indicated concentration (0, 5, and 25 mg/L) of gem for 48 h, cell proliferation was evaluated by 3'-(4, 5 dimethyl-thiazol-2-yl)-2, 5-diphenyl tetrazolium bromide assay; cell morphology was observed by transmission electron microscopy; Expression of c-IAP2 and Bcl-2 proteins was analyzed by Western blot; the activity of caspase-3 and -9 was detected by spectrophotometry. Gem significantly inhibited cell proliferation and could induce apoptosis of human pancreatic cancer PANC-1 cells, with a dose-dependent manner. Western blot analysis showed that gem significantly reduced c-IAP2 and Bcl-2 proteins expression level (P PANC-1 cells. Gem could induce apoptosis of human pancreatic cancer PANC-1 cells, probably through downregulating c-IAP2 and Bcl-2 expression levels, and at the same time activating caspase-3 and -9.

  11. Targeting senescence cells in pancreatic cancer | IDRC ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Targeting senescence cells in pancreatic cancer. Cellular senescence is a programmed response to oncogenic (tumour-causing) stress that aims to halt the expansion of cells with malignant potential. It does this by stopping the proliferation of pre-cancerous lesions and recruitment of the immune system for their elimination.

  12. Blocking Ihh signaling pathway inhibits the proliferation and promotes the apoptosis of PSCs.

    Science.gov (United States)

    Xu, Kai; Guo, Fengjing; Zhang, Shuwei; Liu, Cheng; Wang, Feixiong; Zhou, Zhiguo; Chen, Anmin

    2009-02-01

    The roles of Indian hedgehog (Ihh) signaling pathway in the proliferation and apoptosis of precartilaginous stem cells (PSCs) were investigated. PSCs, labeled with fibroblast growth factor receptor 3 (FGFR-3), were isolated from neonatal rats by immunomagnetic separation. After identification with FGFR-3 and Col II, the cells were incubated with different concentrations of cyclopamine (cyclo), the specific inhibitor of Ihh signaling pathway. The morphologic changes of the cells were observed under the inverted phase contrast microscope. The mRNA expression levels of Ihh, parathyroid hormonerelated peptide (PTHrP), protein Patched (Ptch), Bcl-2 and p21 were detected by RT-PCR. The protein expression levels of Ihh and Ptch were measured by Western blot. MTT assay was used to examine the effects of cyclo on proliferation of PSCs. Apoptosis rate of PSCs was examined by Annexin V/PI assay of flow cytometric analyses. After PSCs were incubated with cyclo, obvious morphologic changes were observed as compared with the control group. The mRNA expression levels of PTHrP, Ptch and Bcl-2 were decreased to varying degrees in a cyclo dose-dependent manner. However, the expression levels of Ihh and p21 mRNA were increased. The protein expression of Ptch and Ihh had the same change as the mRNA expression. Meanwhile, cyclo could obviously inhibit the proliferation and promote the apoptosis of PSCs. The results indicated that Ihh signaling pathway plays an important role in regulating the proliferation and apoptosis of PSCs, which is probably mediated by Bcl-2 and p21.

  13. Molecular basis for the interplay of apoptosis and proliferation mediated by Bcl-xL:Bim interactions in pancreatic cancer cells

    International Nuclear Information System (INIS)

    Abrol, Ravinder; Edderkaoui, Mouad; Goddard, William A.; Pandol, Stephen J.

    2012-01-01

    Highlights: ► Direct role of Bcl-2 protein interactions in cell proliferation is not clear. ► Designed Bcl-xL mutants show opposite effects on apoptosis and proliferation. ► Disrupting Bcl-xL:Bim interaction increased apoptosis in pancreatic cancer. ► Disrupting Bcl-xL:Bim interaction decreased proliferation in pancreatic cancer. ► Bcl-xL:Bim interaction can control both apoptosis and proliferation. -- Abstract: A major mechanism through which cancer cells avoid apoptosis is by promoting the association of anti-apoptotic members of the pro-survival Bcl-2 protein family (like Bcl-2 and Bcl-xL) with BH 3 domain-only proteins (like Bim and Bid). Apoptosis and cell proliferation have been shown to be linked for many cancers but the molecular basis for this link is far from understood. We have identified the Bcl-xL:Bim protein–protein interface as a direct regulator of proliferation and apoptosis in pancreatic cancer cells. We were able to predict and subsequently verify experimentally the effect of various Bcl-xL single-point mutants (at the position A142) on binding to Bim by structural analysis and computational modeling of the inter-residue interactions at the Bcl-xL:Bim protein–protein interface. The mutants A142N, A142Q, and A142Y decreased binding of Bim to Bcl-xL and A142S increased this binding. The Bcl-xL mutants, with decreased affinity for Bim, caused an increase in apoptosis and a corresponding decrease in cell proliferation. However, we could prevent these effects by introducing a small interfering RNA (siRNA) targeted at Bim. These results show a novel role played by the Bcl-xL:Bim interaction in regulating proliferation of pancreatic cancer cells at the expense of apoptosis. This study presents a physiologically relevant model of the Bcl-xL:Bim interface that can be used for rational therapeutic design for the inhibition of proliferation and cancer cell resistance to apoptosis.

  14. Effect of leptin on proliferation and apoptosis of cholangiocarcinoma QBC939 cells

    Directory of Open Access Journals (Sweden)

    DAI Kai

    2013-03-01

    Full Text Available ObjectiveTo determine whether leptin can exert anti-proliferative and pro-apoptotic effects on human cholangiocarcinoma cells and to investigate the underlying molecular mechanisms. MethodsHuman cholangiocarcinoma QBC939 cells were cultured and treated with different concentrations of leptin. Changes in the proliferation rate were measured by the MTT assay. Changes in cell cycle and in the apoptosis incidence rate were detected by flow cytometry. Changes in cyclin D1, bax and bcl-2 gene expression were detected by measuring mRNA levels by real-time quantitative reverse transcription-polymerase chain reaction (qPCR. Changes in caspase-3 protease activity were detected by fluorometric assay. ResultsLeptin treatment significantly increased the proliferation rate of QBC939 cells in a dose- and time-dependent manner. Compared to untreated QBC939 cells, leptin treatment led to significantly more G0/G1 to S phase transition and significantly lower apoptosis rate. In addition, leptin-treated QBC939 cells showed enhanced mRNA expression of cyclin D1 and bcl-2, but decreased mRNA expression of bax. The leptin treatment also led to decreased caspase-3 activity. ConclusionLeptin promotes S to G0/G1 phase transition and proliferation, but inhibits apoptosis, of human cholangiocarcinoma cells in vitro.

  15. Dose-dependent effects of R-sulforaphane isothiocyanate on the biology of human mesenchymal stem cells, at dietary amounts, it promotes cell proliferation and reduces senescence and apoptosis, while at anti-cancer drug doses, it has a cytotoxic effect.

    Science.gov (United States)

    Zanichelli, Fulvia; Capasso, Stefania; Cipollaro, Marilena; Pagnotta, Eleonora; Cartenì, Maria; Casale, Fiorina; Iori, Renato; Galderisi, Umberto

    2012-04-01

    Brassica vegetables are attracting a great deal of attention as healthy foods because of the fact that they contain substantial amounts of secondary metabolite glucosinolates that are converted into isothiocyanates, such as sulforaphane [(-)1-isothiocyanato-4R-(methylsulfinyl)-butane] (R-SFN), through the actions of chopping or chewing the vegetables. Several studies have analyzed the biological and molecular mechanisms of the anti-cancer activity of synthetic R,S-sulforaphane, which is thought to be a result of its antioxidant properties and its ability to inhibit histone deacetylase enzymes (HDAC). Few studies have addressed the possible antioxidant effects of R-SFN, which could protect cells from the free radical damage that strongly contribute to aging. Moreover, little is known about the effect of R-SFN on stem cells whose longevity is implicated in human aging. We evaluated the effects of R-SFN on the biology on human mesenchymal stem cells (MSCs), which, in addition to their ability to differentiate into mesenchymal tissues, support hematopoiesis, and contribute to the homeostatic maintenance of many organs and tissues. Our investigation found evidence that low doses of R-SFN promote MSCs proliferation and protect them from apoptosis and senescence, while higher doses have a cytotoxic effect, leading to the induction of cell cycle arrest, programmed cell death and senescence. The beneficial effects of R-SFN may be ascribed to its antioxidant properties, which were observed when MSC cultures were incubated with low doses of R-SFN. Its cytotoxic effects, which were observed after treating MSCs with high doses of R-SFN, could be attributed to its HDAC inhibitory activity. In summary, we found that R-SFN, like many other dietary supplements, exhibits a hormetic behavior; it is able to induce biologically opposite effects at different doses.

  16. Androgen receptor drives cellular senescence.

    Directory of Open Access Journals (Sweden)

    Yelena Mirochnik

    Full Text Available The accepted androgen receptor (AR role is to promote proliferation and survival of prostate epithelium and thus prostate cancer progression. While growth-inhibitory, tumor-suppressive AR effects have also been documented, the underlying mechanisms are poorly understood. Here, we for the first time link AR anti-cancer action with cell senescence in vitro and in vivo. First, AR-driven senescence was p53-independent. Instead, AR induced p21, which subsequently reduced ΔN isoform of p63. Second, AR activation increased reactive oxygen species (ROS and thereby suppressed Rb phosphorylation. Both pathways were critical for senescence as was proven by p21 and Rb knock-down and by quenching ROS with N-Acetyl cysteine and p63 silencing also mimicked AR-induced senescence. The two pathways engaged in a cross-talk, likely via PML tumor suppressor, whose localization to senescence-associated chromatin foci was increased by AR activation. All these pathways contributed to growth arrest, which resolved in senescence due to concomitant lack of p53 and high mTOR activity. This is the first demonstration of senescence response caused by a nuclear hormone receptor.

  17. EGF signalling pathway regulates colon cancer stem cell proliferation and apoptosis.

    Science.gov (United States)

    Feng, Y; Dai, X; Li, X; Wang, H; Liu, J; Zhang, J; Du, Y; Xia, L

    2012-10-01

    Cancer stem cells (CSCs) compose a subpopulation of cells within a tumour that can self-renew and proliferate. Growth factors such as epidermal growth factor (EGF) and basic fibroblast growth factor (b-FGF) promote cancer stem cell proliferation in many solid tumours. This study assesses whether EGF, bFGF and IGF signalling pathways are essential for colon CSC proliferation and self-renewal. Colon CSCs were cultured in serum-free medium (SFM) with one of the following growth factors: EGF, bFGF or IGF. Characteristics of CSC gene expression were evaluated by real time PCR. Tumourigenicity of CSCs was determined using a xenograft model in vivo. Effects of EGF receptor inhibitors, Gefitinib and PD153035, on CSC proliferation, apoptosis and signalling were evaluated using fluorescence-activated cell sorting and western blotting. Colon cancer cell HCT116 transformed to CSCs in SFM. Compared to other growth factors, EGF was essential to support proliferation of CSCs that expressed higher levels of progenitor genes (Musashi-1, LGR5) and lower levels of differential genes (CK20). CSCs promoted more rapid tumour growth than regular cancer cells in xenografts. EGFR inhibitors suppressed proliferation and induced apoptosis of CSCs by inhibiting autophosphorylation of EGFR and downstream signalling proteins, such as Akt kinase, extracellular signal-regulated kinase 1/2 (ERK 1/2). This study indicates that EGF signalling was essential for formation and maintenance of colon CSCs. Inhibition of the EGF signalling pathway may provide a useful strategy for treatment of colon cancer. © 2012 Blackwell Publishing Ltd.

  18. Yorkie regulates epidermal wound healing in Drosophila larvae independently of cell proliferation and apoptosis.

    Science.gov (United States)

    Tsai, Chang-Ru; Anderson, Aimee E; Burra, Sirisha; Jo, Juyeon; Galko, Michael J

    2017-07-01

    Yorkie (Yki), the transcriptional co-activator of the Hippo signaling pathway, has well-characterized roles in balancing apoptosis and cell division during organ growth control. Yki is also required in diverse tissue regenerative contexts. In most cases this requirement reflects its well-characterized roles in balancing apoptosis and cell division. Whether Yki has repair functions outside of the control of cell proliferation, death, and growth is not clear. Here we show that Yki and Scalloped (Sd) are required for epidermal wound closure in the Drosophila larval epidermis. Using a GFP-tagged Yki transgene we show that Yki transiently translocates to some epidermal nuclei upon wounding. Genetic analysis strongly suggests that Yki interacts with the known wound healing pathway, Jun N-terminal kinase (JNK), but not with Platelet Derived Growth Factor/Vascular-Endothelial Growth Factor receptor (Pvr). Yki likely acts downstream of or parallel to JNK signaling and does not appear to regulate either proliferation or apoptosis in the larval epidermis during wound repair. Analysis of actin structures after wounding suggests that Yki and Sd promote wound closure through actin regulation. In sum, we found that Yki regulates an epithelial tissue repair process independently of its previously documented roles in balancing proliferation and apoptosis. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Effect of valsartan on cardiac senescence and apoptosis in a rat model of cardiotoxicity.

    Science.gov (United States)

    Sakr, Hussein F; Abbas, Amr M; Elsamanoudy, Ayman Z

    2016-06-01

    The clinical application of doxorubicin is limited by its cardiotoxicity. The present study investigated the effect of valsartan on doxorubicin-induced cardiotoxicity in rats. Rats were divided into 6 groups: control, control + valsartan (10 mg/kg, for 14 days, orally), doxorubicin-treated (2.5 mg/kg, 3 times/week for 2 weeks, intraperitoneally), valsartan then doxorubicin, valsartan + doxorubicin, and doxorubicin then valsartan. ECG, isolated heart, lipid peroxidation (thiobaribituric acid reactive substances (TBARS)), total antioxidant capacity (TAC), and Bax, Bcl-2, and senescence marker protein 30 (SMP30) gene expression were measured in cardiac tissue. Blood samples were collected to measure lactate dehydrogenase (LDH) and creatine kinase MB (CK-MB). Doxorubicin significantly increased LDH, CK-MB, TBARS, heart rate (HR), Bax gene expression, and -dP/dtmax and decreased TAC, Bcl-2 and SMP30 gene expression, left ventricular developed pressure (LVDP), and +dP/dtmax. Also, doxorubicin lengthened ST, QT, and QTc intervals. Concurrent or post- but not pre-treatment of doxorubicin-treated rats with valsartan reduced LDH, CK-MB, TBARS, HR, Bax gene expression, -dP/dtmax, and ST, QT, and QTc intervals and increased TAC, Bcl-2 and SMP30 gene expression, LVDP, and +dP/dtmax. Therefore, we conclude that concurrent or post- but not pre-treatment of doxorubicin-induced rats with valsartan attenuated doxorubicin-induced cardiotoxicity through inhibiting oxidative stress, apoptosis, and senescence.

  20. Molecular basis for the interplay of apoptosis and proliferation mediated by Bcl-xL:Bim interactions in pancreatic cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Abrol, Ravinder, E-mail: abrol@wag.caltech.edu [Materials and Process Simulation Center, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125 (United States); Edderkaoui, Mouad [Veterans Affairs Greater Los Angeles Healthcare System and UCLA, Los Angeles, CA 90073 (United States); Goddard, William A. [Materials and Process Simulation Center, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125 (United States); Pandol, Stephen J., E-mail: stephen.pandol@va.gov [Veterans Affairs Greater Los Angeles Healthcare System and UCLA, Los Angeles, CA 90073 (United States)

    2012-06-15

    Highlights: Black-Right-Pointing-Pointer Direct role of Bcl-2 protein interactions in cell proliferation is not clear. Black-Right-Pointing-Pointer Designed Bcl-xL mutants show opposite effects on apoptosis and proliferation. Black-Right-Pointing-Pointer Disrupting Bcl-xL:Bim interaction increased apoptosis in pancreatic cancer. Black-Right-Pointing-Pointer Disrupting Bcl-xL:Bim interaction decreased proliferation in pancreatic cancer. Black-Right-Pointing-Pointer Bcl-xL:Bim interaction can control both apoptosis and proliferation. -- Abstract: A major mechanism through which cancer cells avoid apoptosis is by promoting the association of anti-apoptotic members of the pro-survival Bcl-2 protein family (like Bcl-2 and Bcl-xL) with BH{sub 3} domain-only proteins (like Bim and Bid). Apoptosis and cell proliferation have been shown to be linked for many cancers but the molecular basis for this link is far from understood. We have identified the Bcl-xL:Bim protein-protein interface as a direct regulator of proliferation and apoptosis in pancreatic cancer cells. We were able to predict and subsequently verify experimentally the effect of various Bcl-xL single-point mutants (at the position A142) on binding to Bim by structural analysis and computational modeling of the inter-residue interactions at the Bcl-xL:Bim protein-protein interface. The mutants A142N, A142Q, and A142Y decreased binding of Bim to Bcl-xL and A142S increased this binding. The Bcl-xL mutants, with decreased affinity for Bim, caused an increase in apoptosis and a corresponding decrease in cell proliferation. However, we could prevent these effects by introducing a small interfering RNA (siRNA) targeted at Bim. These results show a novel role played by the Bcl-xL:Bim interaction in regulating proliferation of pancreatic cancer cells at the expense of apoptosis. This study presents a physiologically relevant model of the Bcl-xL:Bim interface that can be used for rational therapeutic design for the

  1. The Role of AKT/mTOR Pathway in Stress Response to UV-Irradiation: Implication in Skin Carcinogenesis by Regulation of Apoptosis, Autophagy and Senescence

    Science.gov (United States)

    Strozyk, Elwira; Kulms, Dagmar

    2013-01-01

    Induction of DNA damage by UVB and UVA radiation may generate mutations and genomic instability leading to carcinogenesis. Therefore, skin cells being repeatedly exposed to ultraviolet (UV) light have acquired multilayered protective mechanisms to avoid malignant transformation. Besides extensive DNA repair mechanisms, the damaged skin cells can be eliminated by induction of apoptosis, which is mediated through the action of tumor suppressor p53. In order to prevent the excessive loss of skin cells and to maintain the skin barrier function, apoptotic pathways are counteracted by anti-apoptotic signaling including the AKT/mTOR pathway. However, AKT/mTOR not only prevents cell death, but is also active in cell cycle transition and hyper-proliferation, thereby also counteracting p53. In turn, AKT/mTOR is tuned down by the negative regulators being controlled by the p53. This inhibition of AKT/mTOR, in combination with transactivation of damage-regulated autophagy modulators, guides the p53-mediated elimination of damaged cellular components by autophagic clearance. Alternatively, p53 irreversibly blocks cell cycle progression to prevent AKT/mTOR-driven proliferation, thereby inducing premature senescence. Conclusively, AKT/mTOR via an extensive cross talk with p53 influences the UV response in the skin with no black and white scenario deciding over death or survival. PMID:23887651

  2. 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.

  3. Down-regulation of long non-coding RNA TUG1 inhibits osteosarcoma cell proliferation and promotes apoptosis.

    Science.gov (United States)

    Zhang, Qiang; Geng, Pei-Liang; Yin, Pei; Wang, Xiao-Lin; Jia, Jin-Peng; Yao, Jie

    2013-01-01

    To investigate the expression level of TUG1 and one of its transcript variants (n377360) in osteosarcoma cells and assess the role of TUG1 in proliferation and apoptosis in the U2OS cell line. TUG1 and n377360 expression levels in patients with osteosarcomas and the U2OS human osteosarcoma cell line were evaluated using real-time quantitative PCR. U2OS cells were transected with TUG1 and n377360 siRNA or non-targeting siRNA. MTS was performed to assess the cell proliferation and flow cytometry was applied to analyze apoptosis. We found significantly higher TUG1 and n377360 expression levels in osteosarcoma tissues compared with matched non-tumorous tissues. In line with this, suppression of TUG1 and n377360 expression by siRNA significantly impaired the cell proliferation potential of osteosarcoma cells. Furthermore, inhibition of TUG1 expression significantly promoted osteosarcoma cell apoptosis. The overexpression of TUG1 and n377360 in osteosarcoma specimens and the functional role of TUG1 and n377360 regarding cell proliferation and apoptosis in an osteosarcoma cell line provided evidence that the use of TUG1 or n377360 may be a viable but an as yet unexplored therapeutic strategy in tumors that over express these factors.

  4. Ghrelin modulates testicular germ cells apoptosis and proliferation in adult normal rats

    International Nuclear Information System (INIS)

    Kheradmand, Arash; Dezfoulian, Omid; Alirezaei, Masoud; Rasoulian, Bahram

    2012-01-01

    Highlights: ► Spermatogenesis is closely associated with the balance between germ cells proliferation and apoptosis. ► Numerous studies have documented the direct action of ghrelin in the modulation of apoptosis in different cell types. ► Ghrelin may be considered as a modulator of spermatogenesis in normal adult rats. ► Ghrelin may be potentially implicated for abnormal spermatogenesis in some testicular germ cell tumors. -- Abstract: Under normal condition in the most mammals, spermatogenesis is closely associated with the balance between germ cells proliferation and apoptosis. The present study was designed to determine the effects of ghrelin treatment on in vivo quality and quantity expression of apoptosis and proliferation specific indices in rat testicular germ cells. Twenty eight adult normal rats were subdivided into equal control and treatment groups. Treatment group received 3 nmol of ghrelin as subcutaneous injection for 30 consecutive days or vehicle to the control animals. The rats from each group (n = 7) were killed on days 10 and 30 and their testes were taken for immunocytochemical evaluation and caspase-3 assay. Immunohistochemical analysis indicated that the accumulations of Bax and PCNA peptides are generally more prominent in spermatocytes and spermatogonia of both groups. Likewise, the mean percentage of immunoreactive spermatocytes against Bax increased (P 0.05). Upstream of Bax substance parallel to down-regulation of PCNA demonstrate that ghrelin may prevent massive accumulation of germ cells during normal spermatogenesis. These observations also indicate that ghrelin may be considered as a modulator of spermatogenesis in normal adult rats and could be potentially implicated for abnormal spermatogenesis in some testicular germ cell tumors.

  5. Comparison between various biomarkers of senescence in bone marrow-derived stromal cells in vitro and ex-vivo

    DEFF Research Database (Denmark)

    Nehlin, Jan; Kassem, Moustapha; Frary, Charles

    Senescent stem cells are classified as non-quiescent, irreversibly growth-arrested, non-terminally differentiated, apoptosis resistant multipotent stem cells that maintain an altered gene expression from their juvenescent precursors. Established markers of senescence such as senescent-associated ...

  6. Modulation of human melanoma cell proliferation and apoptosis by hydatid cyst fluid of Echinococcus granulosus

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    Gao X

    2018-03-01

    Full Text Available Xiang-Yang Gao,1,* Guang-Hui Zhang,2,* Li Huang3 1Department of Laboratory Medicine, Pu’er People’s Hospital, Pu’er, 2Department of Clinical Laboratory, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 3Department of General Surgery, Shanghai General Hospital, Shanghai, China *These authors contributed equally to this work Objective: The objective of this paper was to assess the effects of hydatid cyst fluid (HCF of Echinococcus granulosus on melanoma A375 cell proliferation and apoptosis.Methods: A375 cells were classified into five groups by in vitro culture: normal group, control group, 10% HCF group, 20% HCF group and 30% HCF group. Trypan blue staining method was employed to detect the toxicity of HCF. Effects of different concentrations of HCF on melanoma A375 cell proliferation at different time points were evaluated using the 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide assay. Flow cytometry and propidium iodide (PI staining were used to detect cell cycle, and Annexin-V/PI double staining method was used to determine A375 cell apoptotic rate. Western blotting was applied to detect the expression of phosphorylated extracellular regulated protein kinases, proliferating cell nuclear antigen (PCNA, cell-cycle-related proteins (cyclin A, cyclin B1, cyclin D1 and cyclin E and apoptosis-related proteins (Bcl-2, Bax and caspase-3.Results: HCF with a high concentration was considered as atoxic to A375 cells. HCF promoted A375 cell proliferation, and the effects got stronger with an increase in concentrations but was retarded after reaching a certain range of concentrations. HCF increased phosphorylation level and expression of extracellular regulated protein kinase, as well as PCNA expression. HCF also promoted the transferring progression of A375 cells from the G0/G1 phase to the S phase to increase the cell number in S phase and increased the expression of cyclin A, cyclin D1 and

  7. 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.

  8. 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

  9. EFFECT OF dbcAMP ON PROLIFERATION AND APOPTOSIS OF PORCINE GRANULOSA CELLS in vitro

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    Richard Alexa

    2013-02-01

    Full Text Available Cyclic nucleotide cAMP and its target protein kinase A (PKA dependent intracellular mechanisms can play an important role in regulation of ovarian cell function and in mediating gonadotropin action on these cells. The aim of the present study was to examine the effect of cAMP analogue, dibutyryl cyclic adenosine monophosphate (dbcAMP (0; 0.1; 1 and 10 µg/ml or FSH (0; 0,01; 1 IU/ml on proliferation and apoptosis of porcine granulosa cells in vitro. Indices of cell apoptosis (expression of apoptotic peptide bax and proliferation (expression of proliferation-associated peptide PCNA within ovarian granulosa cells were analysed by immunocytochemistry. It was observed that accumulation of PCNA was increased by dbcAMP and FSH at all doses added. The occurrence of bax was also stimulated by dbcAMP after exposition (at 0,1 and 1 µg/ml, but not at dose 10 µg/ml and by FSH (at all doses added. The stimulatory effect of both dbcAMP and FSH on both ovarian cell apoptosis and proliferation suggest, that these substances may promote ovarian follicular cell turnover. The similarity of dbcAMP and FSH effect may indicate that FSH can affect ovarian functions via cAMP-dependent intracellular mechanisms. The present data may provide new tools to regulate human and animal reproductive processes via cAMP-dependent mechanisms.

  10. Viability, Apoptosis, Proliferation, Activation, and Cytokine Secretion of Human Keratoconus Keratocytes after Cross-Linking

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    Xuefei Song

    2015-01-01

    Full Text Available Purpose. The purpose of this study was to determine the impact of cross-linking (CXL on viability, apoptosis, proliferation, activation, and cytokine secretion of human keratoconus (KC keratocytes, in vitro. Methods. Primary KC keratocytes were cultured in DMEM/Ham’s F12 medium supplemented with 10% FCS and underwent UVA illumination (370 nm, 2 J/cm2 during exposure to 0.1% riboflavin and 20% Dextran in PBS. Twenty-four hours after CXL, viability was assessed using Alamar blue assay; apoptosis using APO-DIRECT Kit; proliferation using ELISA-BrdU kit; and CD34 and alpha-smooth muscle actin (α-SMA expression using flow cytometry. Five and 24 hours after CXL, FGFb, HGF, TGFβ1, VEGF, KGF, IL-1β, IL-6, and IL-8 secretion was measured using enzyme-linked-immunoabsorbent assay (ELISA. Results. Following CXL, cell viability and proliferation decreased (P0.06. Five hours after CXL, FGFb secretion increased significantly (P=0.037; however no other cytokine secretion differed significantly from controls after 5 or 24 hours (P>0.12. Conclusions. Cross-linking decreases viability, triggers apoptosis, and inhibits proliferation, without an impact on multipotent hematopoietic stem cell transformation and myofibroblastic transformation of KC keratocytes. CXL triggers FGFb secretion of KC keratocytes transiently (5 hours, normalizing after 24 hours.

  11. Oncogene-induced senescence is part of the tumorigenesis barrier imposed by DNA damage checkpoints

    DEFF Research Database (Denmark)

    Bartkova, Jirina; Rezaei, Nousin; Liontos, Michalis

    2006-01-01

    Recent studies have indicated the existence of tumorigenesis barriers that slow or inhibit the progression of preneoplastic lesions to neoplasia. One such barrier involves DNA replication stress, which leads to activation of the DNA damage checkpoint and thereby to apoptosis or cell cycle arrest...... and senescence markers cosegregate closely. Thus, senescence in human preneoplastic lesions is a manifestation of oncogene-induced DNA replication stress and, together with apoptosis, provides a barrier to malignant progression....

  12. Effects of fasting and refeeding on intestinal cell proliferation and apoptosis in hammerhead shark (Sphyrna lewini

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    Hideya Takahashi

    2014-04-01

    Full Text Available Objective: To examine the effects of fasting and refeeding on intestinal cell proliferation and apoptosis in an opportunistic predator, hammerhead shark (Sphyrna lewini of elasmobranch fishes which are among the earliest known extant groups of vertebrates to have the valvular intestine typical for the primitive species. Methods: Animals were euthanized after 5-10 d of fasting or feeding, or after 10-day fasting and 5-day refeeding. Intestinal apoptosis and cell proliferation were assessed by using oligonucleotide detection assay, terminal deoxynucleotidyl transferase dUTP nick end labeling staining, and immunohistochemistry of proliferating cells nuclear antigen. Results: Plasma levels of cholesterol and glucose were reduced by fasting. Intestinal apoptosis generally decreased during fasting. Numerous apoptotic cells were observed around the tips of the villi, primarily in the epithelium in the fed sharks, whereas fewer labeled nuclei were detected in the epithelium of fasted sharks. Refeeding returned intestinal apoptosis to the level in the fed sharks. Proliferating cells were observed in the epithelium around the troughs of the villi and greater in number in fed sharks, whereas fewer labeled nuclei were detected in fasted sharks. Conclusions: The cell turnover is modified in both intestinal epithelia of the shark and the murines by fasting/feeding, but in opposite directions. The difference may reflect the feeding ecology of the elasmobranchs, primitive intermittent feeders.

  13. A multiplexed method for kinetic measurements of apoptosis and proliferation using live-content imaging.

    Science.gov (United States)

    Artymovich, Katherine; Appledorn, Daniel M

    2015-01-01

    In vitro cell proliferation and apoptosis assays are widely used to study cancer cell biology. Commonly used methodologies are however performed at a single, user-defined endpoint. We describe a kinetic multiplex assay incorporating the CellPlayer(TM) NucLight Red reagent to measure proliferation and the CellPlayer(TM) Caspase-3/7 reagent to measure apoptosis using the two-color, live-content imaging platform, IncuCyte(TM) ZOOM. High-definition phase-contrast images provide an additional qualitative validation of cell death based on morphological characteristics. The kinetic data generated using this strategy can be used to derive informed pharmacology measurements to screen potential cancer therapeutics.

  14. Oxidative Stress Induces Senescence in Cultured RPE Cells.

    Science.gov (United States)

    Aryan, Nona; Betts-Obregon, Brandi S; Perry, George; Tsin, Andrew T

    2016-01-01

    The aim of this research is to determine whether oxidative stress induces cellular senescence in human retinal pigment epithelial cells. Cultured ARPE19 cells were subjected to different concentrations of hydrogen peroxide to induce oxidative stress. Cells were seeded into 24-well plates with hydrogen peroxide added to cell medium and incubated at 37°C + 5% CO2 for a 90-minute period [at 0, 300, 400 and 800 micromolar (MCM) hydrogen peroxide]. The number of viable ARPE19 cells were recorded using the Trypan Blue Dye Exclusion Method and cell senescence was measured by positive staining for senescence-associated beta-galactosidase (SA-beta-Gal) protein. Without hydrogen peroxide treatment, the number of viable ARPE19 cells increased significantly from 50,000 cells/well to 197,000 within 72 hours. Treatment with hydrogen peroxide reduced this level of cell proliferation significantly (to 52,167 cells at 400 MCM; to 49,263 cells at 800 MCM). Meanwhile, cells with a high level of positive senescence-indicator SA-Beta-Gal-positive staining was induced by hydrogen peroxide treatment (from a baseline level of 12% to 80% at 400 MCM and at 800 MCM). Our data suggests that oxidative stress from hydrogen peroxide treatment inhibited ARPE19 cell proliferation and induced cellular senescence.

  15. Autocrine IL-6 mediates pituitary tumor senescence

    Science.gov (United States)

    Fuertes, Mariana; Ajler, Pablo; Carrizo, Guillermo; Cervio, Andrés; Sevlever, Gustavo; Stalla, Günter K.; Arzt, Eduardo

    2017-01-01

    Cellular senescence is a stable proliferative arrest state. Pituitary adenomas are frequent and mostly benign, but the mechanism for this remains unknown. IL-6 is involved in pituitary tumor progression and is produced by the tumoral cells. In a cell autonomous fashion, IL-6 participates in oncogene-induced senescence in transduced human melanocytes. Here we prove that autocrine IL-6 participates in pituitary tumor senescence. Endogenous IL-6 inhibition in somatotroph MtT/S shRNA stable clones results in decreased SA-β-gal activity and p16INK4a but increased pRb, proliferation and invasion. Nude mice injected with IL-6 silenced clones develop tumors contrary to MtT/S wild type that do not, demonstrating that clones that escape senescence are capable of becoming tumorigenic. When endogenous IL-6 is silenced, cell cultures derived from positive SA-β-gal human tumor samples decrease the expression of the senescence marker. Our results establish that IL-6 contributes to maintain senescence by its autocrine action, providing a natural model of IL-6 mediated benign adenoma senescence. PMID:27902467

  16. Exogenous ghrelin regulates proliferation and apoptosis in the hypotrophic gut mucosa of the rat.

    Science.gov (United States)

    de Segura, Ignacio A Gómez; Vallejo-Cremades, María Teresa; Lomas, Jesús; Sánchez, Miriam F; Caballero, María Isabel; Largo, Carlota; De Miguel, Enrique

    2010-04-01

    Ghrelin is the natural endogenous ligand for growth hormone secretagogue receptors. This peptide regulates energy homeostasis and expenditure and is a potential link between gut absorptive function and growth. We hypothesized that ghrelin may induce a proliferative and antiapoptotic action promoting the recovery of the hypotrophic gut mucosa. Therefore, the aim of the study was to determine the action of exogenous ghrelin following gut mucosal hypotrophia in rats fed an elemental diet. An elemental diet provides readily absorbable simple nutrients and is usually given to patients with absorptive dysfunction. Male Wistar rats (n = 48) were fed the elemental diet for one week to induce mucosal hypotrophy and then treated for another week with systemic ghrelin and pair-fed with either a normoproteic or hyperproteic isocaloric liquid diet. Another group received a standard diet instead of the elemental diet and served as control (normotrophy). The elemental diet induced intestinal hypotrophia characterized by decreased proliferation in the ileum and increased apoptosis in jejunum and ileum. Ghrelin administration restored normal levels of proliferation in the ileum and apoptosis in the jejunum, with partial apoptosis restoration in the ileum. Ghrelin levels in plasma and fundus were increased in all groups, although the highest levels were found in rats treated with exogenous ghrelin. Ghrelin administration has a positive effect in the hypotrophic gut, regulating both proliferation and apoptosis towards a physiological balance counteracting the negative changes induced by an elemental diet in the intestines.

  17. Transcriptional analyses of natural leaf senescence in maize.

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    Wei Yang Zhang

    Full Text Available Leaf senescence is an important biological process that contributes to grain yield in crops. To study the molecular mechanisms underlying natural leaf senescence, we harvested three different developmental ear leaves of maize, mature leaves (ML, early senescent leaves (ESL, and later senescent leaves (LSL, and analyzed transcriptional changes using RNA-sequencing. Three sets of data, ESL vs. ML, LSL vs. ML, and LSL vs. ESL, were compared, respectively. In total, 4,552 genes were identified as differentially expressed. Functional classification placed these genes into 18 categories including protein metabolism, transporters, and signal transduction. At the early stage of leaf senescence, genes involved in aromatic amino acids (AAAs biosynthetic process and transport, cellular polysaccharide biosynthetic process, and the cell wall macromolecule catabolic process, were up-regulated. Whereas, genes involved in amino acid metabolism, transport, apoptosis, and response to stimulus were up-regulated at the late stage of leaf senescence. Further analyses reveals that the transport-related genes at the early stage of leaf senescence potentially take part in enzyme and amino acid transport and the genes upregulated at the late stage are involved in sugar transport, indicating nutrient recycling mainly takes place at the late stage of leaf senescence. Comparison between the data of natural leaf senescence in this study and previously reported data for Arabidopsis implies that the mechanisms of leaf senescence in maize are basically similar to those in Arabidopsis. A comparison of natural and induced leaf senescence in maize was performed. Athough many basic biological processes involved in senescence occur in both types of leaf senescence, 78.07% of differentially expressed genes in natural leaf senescence were not identifiable in induced leaf senescence, suggesting that differences in gene regulatory network may exist between these two leaf senescence

  18. Synergistic effects of rmhTRAIL and 17-AAG on the proliferation and apoptosis of multiple myeloma cells.

    Science.gov (United States)

    Wang, Jing; Li, Yun; Sun, Wei; Liu, Jing; Chen, Wenming

    2018-03-22

    This study aimed to investigate synergistic effects of recombinant mutant human tumor necrosis factor-related apoptosis-inducing ligand (rmhTRAIL) and heat-shock protein 90 (HSP90) inhibitor (geldanamycin derivative 17 -allylamino- 17-demethoxy -geldanamycin, 17-AAG) on the proliferation and apoptosis of multiple myeloma (MM) cells. MTT assays evaluated inhibitory effects of rmhTRAIL and 17-AAG in different concentrations and treatment durations on the proliferation of RPMI8226 and U266 cells. The half maximal inhibitory concentration was calculated using OriginPro7.5. Synergistic effects of rmhTRAIL and 17-AAG on apoptosis of MM cells were detected using flow cytometry at 24 and 48 h post-treatment. To evaluate synergistic effects of rmhTRAIL and 17-AAG, the Q-value was calculated using King's formula. rmhTRAIL exhibited significant inhibitory effects on the proliferation of RPMI8226 cells in a dose- and time-dependent manner (>50%), whereas U266 cells were not sensitive to rmhTRAIL (80%). Significant synergistic effects of rmhTRAIL and 17-AAG on the proliferation of RPMI8226 cells were revealed (Q-value > 1.15), whereas synergistic effects were not evident on the proliferation of U266 cells (Q-value effects on apoptosis of RPMI8226 and U266 cells (Q-value > 1.15). The combined application of rmhTRAIL and 17-AAG revealed favorable synergistic effects in the treatment of MM.

  19. Downregulation of miR-130b~301b cluster is mediated by aberrant promoter methylation and impairs cellular senescence in prostate cancer

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    João Ramalho-Carvalho

    2017-02-01

    Full Text Available Abstract Background Numerous DNA-damaging cellular stresses, including oncogene activation and DNA-damage response (DDR, may lead to cellular senescence. Previous observations linked microRNA deregulation with altered senescent patterns, prompting us to investigate whether epigenetic repression of microRNAs expression might disrupt senescence in prostate cancer (PCa cells. Methods Differential methylation mapping in prostate tissues was carried using Infinium HumanMethylation450 BeadChip. After validation of methylation and expression analyses in a larger series of prostate tissues, the functional role of the cluster miR-130b~301b was explored using in vitro studies testing cell viability, apoptosis, invasion and DNA damage in prostate cancer cell lines. Western blot and RT-qPCR were performed to support those observations. Results We found that the miR-130b~301b cluster directs epigenetic activation of cell cycle inhibitors required for DDR activation, thus stimulating the senescence-associated secretory phenotype (SASP. Furthermore, overexpression of miR-130b~301b cluster markedly reduced the malignant phenotype of PCa cells. Conclusions Altogether, these data demonstrate that miR-130b~301b cluster overexpression might effectively induce PCa cell growth arrest through epigenetic regulation of proliferation-blocking genes and activation of cellular senescence.

  20. Modulation of Cell Cycle Profile by Chlorella vulgaris Prevents Replicative Senescence of Human Diploid Fibroblasts

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    Tayyebeh Saberbaghi

    2013-01-01

    Full Text Available In this study, the effects of Chlorella vulgaris (CV on replicative senescence of human diploid fibroblasts (HDFs were investigated. Hot water extract of CV was used to treat HDFs at passages 6, 15, and 30 which represent young, presenescence, and senescence ages, respectively. The level of DNA damage was determined by comet assay while apoptosis and cell cycle profile were determined using FACSCalibur flow cytometer. Our results showed direct correlation between increased levels of damaged DNA and apoptosis with senescence in untreated HDFs (P<0.05. Cell cycle profile showed increased population of untreated senescent cells that enter G0/G1 phase while the cell population in S phase decreased significantly (P<0.05. Treatment with CV however caused a significant reduction in the level of damaged DNA and apoptosis in all age groups of HDFs (P<0.05. Cell cycle analysis showed that treatment with CV increased significantly the percentage of senescent HDFs in S phase and G2/M phases but decreased the population of cells in G0/G1 phase (P<0.05. In conclusion, hot water extract of Chlorella vulgaris effectively decreased the biomarkers of ageing, indicating its potential as an antiageing compound.

  1. Leptin Regulates Proliferation and Apoptosis in Human Prostate

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    Eduardo Leze

    2012-01-01

    Full Text Available This paper aimed to evaluate the leptin role on the cellular proliferation and the expression of fibroblast growth factor 2, aromatase enzyme, and apoptotic genes in the human prostate tissue. Methods. Fifteen samples of hyperplasic prostate tissue were divided in four symmetric parts maintained in RPMI medium supplemented with 10% fetal bovine serum, 1 ng/mL of gentamicin, and added with 50 ng/mL leptin (L or not (C. After 3 hours of incubation, gene expression was evaluated by real time RT-PCR. Cellular proliferation was evaluated by immunohistochemistry for PCNA. Results. The leptin treatment led to an increase cellular proliferation (C=21.8±0.5; L=64.8±0.9; P<0.0001 and in the expression of Bax (C=0.4±0.1; L=0.9±0.2; P<0.05 while Bcl-2 (C=19.9±5.6; L=5.6±1.8; P<0.05, Bcl-x (C=0.2±0.06; L=0.07±0.02; P<0.05, and aromatase expressions (C=1.9±0.6; L=0.4±0.1; P<0.04 were significantly reduced. Conclusion. Leptin has an important role in maintaining the physiological growth of the prostate since it stimulates both cellular proliferation and apoptosis, with the decrement in the aromatase gene expression.

  2. Senescent phenotypes of skin fibroblasts from patients with Tangier disease

    International Nuclear Information System (INIS)

    Matsuura, Fumihiko; Hirano, Ken-ichi; Ikegami, Chiaki; Sandoval, Jose C.; Oku, Hiroyuki; Yuasa-Kawase, Miyako; Tsubakio-Yamamoto, Kazumi; Koseki, Masahiro; Masuda, Daisaku; Tsujii, Ken-ichi; Ishigami, Masato; Nishida, Makoto; Shimomura, Iichiro; Hori, Masatsugu; Yamashita, Shizuya

    2007-01-01

    Tangier disease (TD) is characterized by a deficiency of high density lipoprotein (HDL) in plasma and patients with TD have an increased risk for coronary artery disease (CAD). Recently, we reported that fibroblasts from TD exhibited large and flattened morphology, which is often observed in senescent cells. On the other hand, data have accumulated to show the relationship between cellular senescence and development of atherosclerotic CAD. The aim of the present study was to investigate whether TD fibroblasts exhibited cellular senescence. The proliferation of TD fibroblasts was gradually decreased at population doubling level (PDL) ∼10 compared with control cells. TD cells practically ceased proliferation at PDL ∼30. DNA synthesis was markedly decreased in TD fibroblasts. TD cells exhibited a higher positive rate for senescence-associated β-galactosidase (SA-β-gal), which is one of the biomarkers of cellular senescence in vitro. These data showed that TD cells reached cellular senescence at an earlier PDL compared with controls. Although, there was no difference in the telomere length of fibroblasts between TD and controls at the earlier passage (PDL 6), the telomere length of TD cells was shorter than that of controls at the late passage (PDL 25). Taken together, the current study demonstrates that the late-passaged TD fibroblasts showed senescent phenotype in vitro, which might be related to the increased cardiovascular manifestations in TD patients

  3. CLCA2 as a p53-Inducible Senescence Mediator

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    Chizu Tanikawa

    2012-02-01

    Full Text Available p53 is a tumor suppressor gene that is frequently mutated in multiple cancer tissues. Activated p53 protein regulates its downstream genes and subsequently inhibits malignant transformation by inducing cell cycle arrest, apoptosis, DNA repair, and senescence. However, genes involved in the p53-mediated senescence pathway are not yet fully elucidated. Through the screening of two genome-wide expression profile data sets, one for cells in which exogenous p53 was introduced and the other for senescent fibroblasts, we have identified chloride channel accessory 2 (CLCA2 as a p53-inducible senescence-associated gene. CLCA2 was remarkably induced by replicative senescence as well as oxidative stress in a p53-dependent manner. We also found that ectopically expressed CLCA2 induced cellular senescence, and the down-regulation of CLCA2 by small interfering RNA caused inhibition of oxidative stress-induced senescence. Interestingly, the reduced expression of CLCA2 was frequently observed in various kinds of cancers including prostate cancer, whereas its expression was not affected in precancerous prostatic intraepithelial neoplasia. Thus, our findings suggest a crucial role of p53/CLCA2-mediated senescence induction as a barrier for malignant transformation.

  4. [RNA interference of HERC4 inhibits proliferation, apoptosis and migration of cervical cancer Hela cells].

    Science.gov (United States)

    Wei, Min; Zhang, Yan-Ling; Chen, Lan; Cai, Cui-Xia; Wang, Han-Duo

    2016-02-20

    To explore the effects of silencing HERC4 on the proliferation, apoptosis, and migration of cervical cancer cell line Hela and the possible molecular mechanisms. Three HERC4-specific small interfering RNAs (siRNAs) were transfected into Hela cells, and HERC4 expression in the cells was examined with Western blotting. CCK-8 assay, annexin V-FITC/PI assay, and wound healing assay were used to assess the effect of HERC4 silencing on the proliferation, apoptosis and migration ability of Hela cells. The expression levels of cyclin D1 and Bcl-2 in the cells were detected using Western blotting. Transfection of siRNA-3 resulted in significantly decreased HERC4 protein expression (PHela cells, increased the apoptosis rate (PHela cells in vitro, and the underlying mechanisms may involve the down-regulation of cyclin D1 and Bcl-2.

  5. ING1 induces apoptosis through direct effects at the mitochondria

    DEFF Research Database (Denmark)

    Bose, P; Thakur, S; Thalappilly, S

    2013-01-01

    The ING family of tumor suppressors acts as readers and writers of the histone epigenetic code, affecting DNA repair, chromatin remodeling, cellular senescence, cell cycle regulation and apoptosis. The best characterized member of the ING family, ING1,interacts with the proliferating cell nuclear....... Bioinformatic analysis of the yeast interactome indicates that yeast ING proteins interact with 64 mitochondrial proteins. Also, sequence analysis of ING1 reveals the presence of a BH3-like domain. These data suggest a model in which stress-induced cytoplasmic relocalization of ING1 by14-3-3 induces ING1-BAX...

  6. Inhibition of doxorubicin-induced senescence by PPARδ activation agonists in cardiac muscle cells: cooperation between PPARδ and Bcl6.

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    Paola Altieri

    Full Text Available Senescence and apoptosis are two distinct cellular programs that are activated in response to a variety of stresses. Low or high doses of the same stressor, i.e., the anticancer drug doxorubicin, may either induce apoptosis or senescence, respectively, in cardiac muscle cells. We have demonstrated that PPARδ, a ligand-activated transcriptional factor that controls lipid metabolism, insulin sensitivity and inflammation, is also involved in the doxorubicin-induced senescence program. This occurs through its interference with the transcriptional repressor protein B cell lymphoma-6 (Bcl6. Low doses of doxorubicin increase the expression of PPARδ that sequesters Bcl6, thus preventing it from exerting its anti-senescent effects. We also found that L-165041, a specific PPARδ activator, is highly effective in protecting cardiomyocytes from doxorubicin-induced senescence through a Bcl6 related mechanism. In fact, L-165041 increases Bcl6 expression via p38, JNK and Akt activation, and at the same time it induces the release of Bcl6 from PPARδ, thereby enabling Bcl6 to bind to its target genes. L-165041 also prevented apoptosis induced by higher doses of doxorubicin. However, while experiments performed with siRNA analysis techniques very clearly showed the weight of Bcl6 in the cellular senescence program, no role was found for Bcl6 in the anti-apoptotic effects of L-165041, thus confirming that senescence and apoptosis are two very distinct stress response cellular programs. This study increases our understanding of the molecular mechanism of anthracycline cardiotoxicity and suggests a potential role for PPARδ agonists as cardioprotective agents.

  7. Ghrelin modulates testicular germ cells apoptosis and proliferation in adult normal rats

    Energy Technology Data Exchange (ETDEWEB)

    Kheradmand, Arash, E-mail: arashkheradmand@yahoo.com [Department of Clinical Sciences, School of Veterinary Medicine, Lorestan University, P.O. Box: 465, Khorram Abad (Iran, Islamic Republic of); Dezfoulian, Omid [Department of Pathobiology, School of Veterinary Medicine, Lorestan University, Khorram Abad (Iran, Islamic Republic of); Alirezaei, Masoud [Division of Biochemistry, School of Veterinary Medicine, Lorestan University, P.O. Box: 465, Khorram Abad (Iran, Islamic Republic of); Rasoulian, Bahram [Razi Herbal Medicine Research Center, Lorestan University of Medical Sciences, Khorram Abad (Iran, Islamic Republic of)

    2012-03-09

    Highlights: Black-Right-Pointing-Pointer Spermatogenesis is closely associated with the balance between germ cells proliferation and apoptosis. Black-Right-Pointing-Pointer Numerous studies have documented the direct action of ghrelin in the modulation of apoptosis in different cell types. Black-Right-Pointing-Pointer Ghrelin may be considered as a modulator of spermatogenesis in normal adult rats. Black-Right-Pointing-Pointer Ghrelin may be potentially implicated for abnormal spermatogenesis in some testicular germ cell tumors. -- Abstract: Under normal condition in the most mammals, spermatogenesis is closely associated with the balance between germ cells proliferation and apoptosis. The present study was designed to determine the effects of ghrelin treatment on in vivo quality and quantity expression of apoptosis and proliferation specific indices in rat testicular germ cells. Twenty eight adult normal rats were subdivided into equal control and treatment groups. Treatment group received 3 nmol of ghrelin as subcutaneous injection for 30 consecutive days or vehicle to the control animals. The rats from each group (n = 7) were killed on days 10 and 30 and their testes were taken for immunocytochemical evaluation and caspase-3 assay. Immunohistochemical analysis indicated that the accumulations of Bax and PCNA peptides are generally more prominent in spermatocytes and spermatogonia of both groups. Likewise, the mean percentage of immunoreactive spermatocytes against Bax increased (P < 0.01) in the ghrelin-treated group on day 10, while despite of 30% increment in the Bax level of spermatocytes in the treated rats on day 30, however, it was not statistically significant. During the experimental period, only a few spermatogonia represented Bax expression and the changes of Bax immunolabling cells were negligible upon ghrelin treatment. Likewise, there were immunostaining cells against Bcl-2 in each germ cell neither in the control nor in the treated animals. In fact

  8. Oxidative stress induces senescence in human mesenchymal stem cells

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    Brandl, Anita [Department of Anesthesiology, University Medical Center Regensburg, Franz-Josef-Strauss-Allee 11, 93042 Regensburg (Germany); Meyer, Matthias; Bechmann, Volker [Department of Trauma Surgery, University Medical Center Regensburg, Franz-Josef-Strauss-Allee 11, 93042 Regensburg (Germany); Nerlich, Michael [Department of Anesthesiology, University Medical Center Regensburg, Franz-Josef-Strauss-Allee 11, 93042 Regensburg (Germany); Angele, Peter, E-mail: Peter.Angele@klinik.uni-regensburg.de [Department of Trauma Surgery, University Medical Center Regensburg, Franz-Josef-Strauss-Allee 11, 93042 Regensburg (Germany)

    2011-07-01

    Mesenchymal stem cells (MSCs) contribute to tissue repair in vivo and form an attractive cell source for tissue engineering. Their regenerative potential is impaired by cellular senescence. The effects of oxidative stress on MSCs are still unknown. Our studies were to investigate into the proliferation potential, cytological features and the telomere linked stress response system of MSCs, subject to acute or prolonged oxidant challenge with hydrogen peroxide. Telomere length was measured using the telomere restriction fragment assay, gene expression was determined by rtPCR. Sub-lethal doses of oxidative stress reduced proliferation rates and induced senescent-morphological features and senescence-associated {beta}-galactosidase positivity. Prolonged low dose treatment with hydrogen peroxide had no effects on cell proliferation or morphology. Sub-lethal and prolonged low doses of oxidative stress considerably accelerated telomere attrition. Following acute oxidant insult p21 was up-regulated prior to returning to initial levels. TRF1 was significantly reduced, TRF2 showed a slight up-regulation. SIRT1 and XRCC5 were up-regulated after oxidant insult and expression levels increased in aging cells. Compared to fibroblasts and chondrocytes, MSCs showed an increased tolerance to oxidative stress regarding proliferation, telomere biology and gene expression with an impaired stress tolerance in aged cells.

  9. Mechanisms of growth inhibition of primary prostate epithelial cells following gamma irradiation or photodynamic therapy include senescence, necrosis, and autophagy, but not apoptosis

    International Nuclear Information System (INIS)

    Frame, Fiona M.; Savoie, Huguette; Bryden, Francesca; Giuntini, Francesca; Mann, Vincent M.; Simms, Matthew S.; Boyle, Ross W.; Maitland, Norman J.

    2015-01-01

    In comparison to more differentiated cells, prostate cancer stem-like cells are radioresistant, which could explain radio-recurrent prostate cancer. Improvement of radiotherapeutic efficacy may therefore require combination therapy. We have investigated the consequences of treating primary prostate epithelial cells with gamma irradiation and photodynamic therapy (PDT), both of which act through production of reactive oxygen species (ROS). Primary prostate epithelial cells were cultured from patient samples of benign prostatic hyperplasia and prostate cancer prior to treatment with PDT or gamma irradiation. Cell viability was measured using MTT and alamar blue assay, and cell recovery by colony-forming assays. Immunofluorescence of gamma-H2AX foci was used to quantify DNA damage, and autophagy and apoptosis were assessed using Western blots. Necrosis and senescence were measured by propidium iodide staining and beta-galactosidase staining, respectively. Both PDT and gamma irradiation reduced the colony-forming ability of primary prostate epithelial cells. PDT reduced the viability of all types of cells in the cultures, including stem-like cells and more differentiated cells. PDT induced necrosis and autophagy, whereas gamma irradiation induced senescence, but neither treatment induced apoptosis. PDT and gamma irradiation therefore inhibit cell growth by different mechanisms. We suggest these treatments would be suitable for use in combination as sequential treatments against prostate cancer

  10. Role of PD 0332991 on the Proliferation and Apoptosis of Vascular Endothelial Cells

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    Chenlong ZHAO

    2018-05-01

    Full Text Available Background and objective Angiogenesis is an important process in the development of tumor. PD 0332991, a cell cycle inhibitor, can specifically inhibit CD4/6 phosphorylation and cell cycle progression. In xeongraft mice models, PD 0332991 treated mice had significantly decreased angiogenesis and vascular density compared with the control group, but the mechanism remains unknown. The purpose of this study is to investigate the role and molecular mechanism of PD 0332991 on vascular endothelial cells. Methods EA.hy926 cells, a kind of vascular endothelial cell, were used as the research model. The effects of PD 0332991 on the activity and proliferation of EA.hy926 cells were detected by the MTT, EdU assays. Wound-healing assays and transwell assays were used to determine the effects of PD 0332991 on the mobility of EA.hy926. The influence of PD 0332991 on cell cycle and apoptosis of endothelial cells was tested by flow cytometry, and the Western blot was applied to observe the expression of cell cycle related proteins in EA.hy926 cells treated by PD 0332991. Results PD 0332991 significantly inhibited the proliferation and mobility of EA.hy926 cells, caused cell cycle arrest and apoptosis. At the same time, PD 0332991 inhibited the expression of CDK4/6 and phosphorylation of Rb, and thus inhibited the cell cycle progression of EA.hy926 cells. Conclusion PD 0332991 can inhibit the proliferation and activity of endothelial cells and induces apoptosis.

  11. Inhibition of phosphatidylcholine-specific phospholipase C prevents bone marrow stromal cell senescence in vitro.

    Science.gov (United States)

    Sun, Chunhui; Wang, Nan; Huang, Jie; Xin, Jie; Peng, Fen; Ren, Yinshi; Zhang, Shangli; Miao, Junying

    2009-10-01

    Bone marrow stromal cells (BMSCs) can proliferate in vitro and can be transplanted for treating many kinds of diseases. However, BMSCs become senescent with long-term culture, which inhibits their application. To understand the mechanism underlying the senescence, we investigated the activity of phosphatidylcholine-specific phospholipase C (PC-PLC) and levels of integrin beta4, caveolin-1 and ROS with BMSC senescence. The activity of PC-PLC and levels of integrin beta4, caveolin-1 and ROS increased greatly during cell senescence. Selective inhibition of increased PC-PLC activity with D609 significantly decreased the number of senescence-associated beta galactosidase positive cells in BMSCs. Furthermore, D609 restored proliferation of BMSCs and their differentiation into adipocytes. Moreover, D609 suppressed the elevated levels of integrin beta4, caveolin-1 and ROS. The data suggest that PC-PLC is involved in senescence of BMSCs, and its function is associated with integrin beta4, caveolin-1 and ROS. (c) 2009 Wiley-Liss, Inc.

  12. An imbalance between apoptosis and proliferation contributes to follicular persistence in polycystic ovaries in rats

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    Neme Leandro G

    2009-07-01

    Full Text Available Abstract Background Cystic ovarian disease is an important cause of infertility that affects bovine, ovine, caprine and porcine species and even human beings. Alterations in the ovarian micro-environment of females with follicular cysts could alter the normal processes of proliferation and programmed cell death in ovarian cells. Thus, our objective was to evaluate apoptosis and proliferation in ovarian cystic follicles in rats in order to investigate the cause of cystic follicle formation and persistence. Methods We compared the number of in situ apoptotic cells by TUNEL assay, expression of active caspase-3 and members of Bcl-2 family by immunohistochemistry; and cell proliferation by the expression of the proliferation markers: PCNA and Ki-67. Results The proliferation index was low in granulosa of tertiary and cystic follicles of light exposed rats when compared with tertiary follicles of control animals, while in theca interna only cystic follicles presented low proliferation index when compared with tertiary follicles (p Conclusion These results show that the combination of weak proliferation indices and low apoptosis observed in follicular cysts, could explain the cause of the slow growth of cystic follicles and the maintenance of a static condition without degeneration, which leads to their persistence. These alterations may be due to structural and functional modifications that take place in these cells and could be related to hormonal changes in animals with this condition.

  13. [Effects of metformin on human oral cancer KB cell proliferation and apoptosis in vitro].

    Science.gov (United States)

    Wang, Fang; Xu, Jincheng; Xia, Fei; Liu, Zhe; Zhao, Surong; Liu, Hao; Jiang, Zhiwen

    2014-02-01

    To investigate the effects of metformin on the proliferation and apoptosis of human oral cancer cell line KB in vitro. Human oral cancer cell line KB was exposed to different doses of metformin (0, 1.25, 2.5, 5, 10, and 20 mmol/L), and the changes in cell viability were detected using MTT assay. Colony formation of the cells was observed following an 8-day metformin exposure. The changes in mitochondrial membrane potential were measured by JC-1 assay, and PI staining was used to observe the cell apoptosis. Western blotting was employed to detect the changes in the protein expressions of GRP78 and activated caspase-3. Metformin exposure caused time- and dose-dependent suppression of KB cell proliferation, and exposure to 5 mmol/L metformin for 24, 48 and 72 h resulted in cell survival rates of 68.0%, 36.9%, and 14.5%, respectively. Metformin significantly inhibited KB cell colony formation. Exposure of the cells to increased concentrations of metformin gradually increased the apoptotic rate and decreased mitochondrial membrane potential. Metformin caused an initial up-regulation followed by a down-regulation of GRP78 expression in KB cells and increased the expression of activated caspase-3. Metformin can inhibit the proliferation and induce apoptosis of KB cells, the mechanism of which may involve the activation of the mitochondrial apoptotic pathway and endoplasmic reticulum stress.

  14. 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

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

    Science.gov (United States)

    Yin, Haoyuan; Shao, Ying; Chen, Xuan

    2017-01-01

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

  16. Aryl hydrocarbon receptor-dependent regulation of miR-196a expression controls lung fibroblast apoptosis but not proliferation

    International Nuclear Information System (INIS)

    Hecht, Emelia; Zago, Michela; Sarill, Miles; Rico de Souza, Angela; Gomez, Alvin; Matthews, Jason; Hamid, Qutayba; Eidelman, David H.; Baglole, Carolyn J.

    2014-01-01

    The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor implicated in the regulation of apoptosis and proliferation. Although activation of the AhR by xenobiotics such as dioxin inhibits the cell cycle and control apoptosis, paradoxically, AhR expression also promotes cell proliferation and survival independent of exogenous ligands. The microRNA (miRNA) miR-196a has also emerged as a regulator of proliferation and apoptosis but a relationship between the AhR and miR-196a is not known. Therefore, we hypothesized that AhR-dependent regulation of endogenous miR-196a expression would promote cell survival and proliferation. Utilizing lung fibroblasts from AhR deficient (AhR −/− ) and wild-type (AhR +/+ ) mice, we show that there is ligand-independent regulation of miRNA, including low miR-196a in AhR −/− cells. Validation by qRT-PCR revealed a significant decrease in basal expression of miR-196a in AhR −/− compared to AhR +/+ cells. Exposure to AhR agonists benzo[a]pyrene (B[a]P) and FICZ as well as AhR antagonist CH-223191 decreased miR-196a expression in AhR +/+ fibroblasts concomitant with decreased AhR protein levels. There was increased proliferation only in AhR +/+ lung fibroblasts in response to serum, corresponding to a decrease in p27 KIP1 protein, a cyclin-dependent kinase inhibitor. Increasing the cellular levels of miR-196a had no effect on proliferation or expression of p27 KIP1 in AhR −/− fibroblasts but attenuated cigarette smoke-induced apoptosis. This study provides the first evidence that AhR expression is essential for the physiological regulation of cellular miRNA levels- including miR-196a. Future experiments designed to elucidate the functional relationship between the AhR and miR-196a may delineate additional novel ligand-independent roles for the AhR. - Highlights: • The AhR controls proliferation and apoptosis in lung cells. • The AhR regulates the expression of the microRNA miR-196a independent of

  17. Fisetin inhibits the proliferation of gastric cancer cells and induces apoptosis through suppression of ERK 1/2 activation.

    Science.gov (United States)

    Yan, Weixin; Chen, Shouhui; Zhao, Yiyang; Ye, Xiaoyu

    2018-06-01

    The present study aimed to investigate the effect of fisetin on proliferation and apoptosis of gastric cancer cells, as well as the underlying mechanism. Proliferation in SGC7901 cancer and GES-1 normal cells was analyzed using a CCK-8 assay. Apoptosis was analyzed using an Annexin V/Propidium Iodide apoptosis kit and phosphorylation of extracellular signal-regulated kinase (ERK) 1/2 was analyzed by western blot assay. Treatment of SGC7901 cells with various concentrations (1, 5, 10, 15 and 20 µM) of fisetin for 48 h resulted in a concentration dependent reduction in proliferation. Flow cytometry revealed a marked increase in apoptosis from 5 µM concentration of fisetin after 48 h. The percentage of apoptotic cells increased to 87% following treatment with 15 µM fisetin for 48 h, compared with 2% in control. Treatment of SGC7901 cells with fisetin for 48 h resulted in a reduction in the activation of ERK 1/2 in a concentration-dependent manner. The reduction in activation of ERK 1/2 was significant following treatment with 15 µM fisetin for 48 h. The inhibitory effect of fisetin on activation of ERK 1/2 was further demonstrated using the ERK 1/2 inhibitor, PD98059. The results indicated a significant reduction in the proliferation of SGC7901 cells following treatment with PD98059 (P<0.002). The reduction by PD98059 administration was comparable to that observed following fisetin treatment for 48 h. In conclusion, the current study demonstrates that fisetin inhibits the proliferation of gastric cancer cells and induces apoptosis through suppression of ERK 1/2 activation. Thus, fisetin may have therapeutic applications in the treatment of gastric cancer.

  18. New agents that target senescent cells : The flavone, fisetin, and the BCL-X-L inhibitors, A1331852 and A1155463

    NARCIS (Netherlands)

    Zhu, Yi; Doornebal, Ewald J.; Pirtskhalava, Tamar; Giorgadze, Nino; Wentworth, Mark; Fuhrmann-Stroissnigg, Heike; Niedernhofer, Laura J.; Robbins, Paul D.; Tchkonia, Tamara; Kirkland, James L.

    2017-01-01

    Senescent cells accumulate with aging and at sites of pathology in multiple chronic diseases. Senolytics are drugs that selectively promote apoptosis of senescent cells by temporarily disabling the pro-survival pathways that enable senescent cells to resist the pro-apoptotic, pro-inflammatory

  19. Single-wall carbon nanohorns (SWNHs) inhibited proliferation of human glioma cells and promoted its apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yunjun [The Military General Hospital of Beijing PLA, Affiliated Bayi Brain Hospital (China); Zhang, Jinqian, E-mail: jingwanghou@yahoo.com.cn [Capital Medical University, Institute of Infectious Diseases, Beijing Ditan Hospital (China); Zhao, Ming [Peking University, Department of Chemical Biology, School of Pharmaceutical Sciences (China); Shi, Zujin [Peking University, Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering (China); Chen, Xin; He, Xihui; Han, Nanyin, E-mail: jingwanghou@sina.com [Peking University, Department of Chemical Biology, School of Pharmaceutical Sciences (China); Xu, Ruxiang, E-mail: everbright999@163.com [The Military General Hospital of Beijing PLA, Affiliated Bayi Brain Hospital (China)

    2013-08-15

    Although single-wall carbon nanohorns (SWNHs) have been demonstrated to accumulate to cytotoxic levels within organs of various animal models and cell types, they have been exploited for cancer therapies. The role of SWNHs in human glioma cell lines was unclear. To address this question, the research about direct role of SWNHs on the growth, proliferation, and apoptosis of human glioma cell lines (U87, U251, and U373) had been performed. Our results indicate that particle size of SWNHs in water is between 342 and 712 nm, the films of SEM show that SWNHs on PS surface are individual particles. SWNHs significantly delayed mitotic entry of human glioma cell lines cells, and inhibited its proliferation in a time- and dose-dependent manner. SWNHs induced a significant increase in G1 phase and inhibition of S phase followed the gradually increasing concentrations. SWNHs in human glioma cell lines cells significantly induced apoptosis followed by their gradually increasing concentrations. The TEM images showed that individual spherical SWNHs particles smaller than 100 nm in diameters were localized inside lysosomes of human glioma cell lines. SWNHs inhibited mitotic entry, growth, and proliferation of human glioma cell lines, and promoted its apoptosis. SWNHs may be a novel opportunity or method for the research on treatment of human glioma.

  20. Single-wall carbon nanohorns (SWNHs) inhibited proliferation of human glioma cells and promoted its apoptosis

    Science.gov (United States)

    Li, Yunjun; Zhang, Jinqian; Zhao, Ming; Shi, Zujin; Chen, Xin; He, Xihui; Han, Nanyin; Xu, Ruxiang

    2013-08-01

    Although single-wall carbon nanohorns (SWNHs) have been demonstrated to accumulate to cytotoxic levels within organs of various animal models and cell types, they have been exploited for cancer therapies. The role of SWNHs in human glioma cell lines was unclear. To address this question, the research about direct role of SWNHs on the growth, proliferation, and apoptosis of human glioma cell lines (U87, U251, and U373) had been performed. Our results indicate that particle size of SWNHs in water is between 342 and 712 nm, the films of SEM show that SWNHs on PS surface are individual particles. SWNHs significantly delayed mitotic entry of human glioma cell lines cells, and inhibited its proliferation in a time- and dose-dependent manner. SWNHs induced a significant increase in G1 phase and inhibition of S phase followed the gradually increasing concentrations. SWNHs in human glioma cell lines cells significantly induced apoptosis followed by their gradually increasing concentrations. The TEM images showed that individual spherical SWNHs particles smaller than 100 nm in diameters were localized inside lysosomes of human glioma cell lines. SWNHs inhibited mitotic entry, growth, and proliferation of human glioma cell lines, and promoted its apoptosis. SWNHs may be a novel opportunity or method for the research on treatment of human glioma.

  1. Effect of helicobacter pylori L-form infection on proliferation, apoptosis and invasion molecule expression in gastric cancer tissue

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    Hua Xin

    2017-05-01

    Full Text Available Objective: To study the effect of Helicobacter pylori L-form infection on proliferation, apoptosis and invasion molecule expression in gastric cancer tissue. Methods: The gastric cancer tissues surgically removed in our hospital between May 2013 and October 2016 were collected and divided into Hp negative, Hp-L negative and Hp-L positive according to the condition of helicobacter pylori infection. The proliferation, apoptosis and invasion gene expression were detected. Results: LOXL2, PCNA, CyclinD1, Rab1A, Bcl-2, Snail, N-cadherin, UHRF1 and AnnexinII mRNA expression in Hp-L-positive gastric cancer tissues were significantly higher than those in Hp-L-negative and Hp-negative gastric cancer tissues while ING5, PTPN13, Beclin1 and Mst1 mRNA expression were significantly lower than those in Hp-L-negative and Hp-negative gastric cancer tissues; LOXL2, PCNA, CyclinD1, Rab1A, Bcl-2, ING5, PTPN13, Beclin1, Mst1, Snail, N-cadherin, UHRF1 and AnnexinII mRNA expression in Hp-L-negative gastric cancer tissues were not different from those in Hpnegative gastric cancer tissues. Conclusion: Helicobacter pylori L-form infection can influence the proliferation, apoptosis and invasion gene expression to promote cell proliferation and invasion, and inhibit cell apoptosis.

  2. [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

  3. The DNA glycosylases OGG1 and NEIL3 influence differentiation potential, proliferation, and senescence-associated signs in neural stem cells

    International Nuclear Information System (INIS)

    Reis, Amilcar; Hermanson, Ola

    2012-01-01

    Highlights: ► DNA glycosylases OGG1 and NEIL3 are required for neural stem cell state. ► No effect on cell viability by OGG1 or NEIL3 knockdown in neural stem cells. ► OGG1 or NEIL3 RNA knockdown result in decreased proliferation and differentiation. ► Increased HP1γ immunoreactivity after NEIL3 knockdown suggests premature senescence. -- Abstract: Embryonic neural stem cells (NSCs) exhibit self-renewal and multipotency as intrinsic characteristics that are key parameters for proper brain development. When cells are challenged by oxidative stress agents the resulting DNA lesions are repaired by DNA glycosylases through the base excision repair (BER) pathway as a means to maintain the fidelity of the genome, and thus, proper cellular characteristics. The functional roles for DNA glycosylases in NSCs have however remained largely unexplored. Here we demonstrate that RNA knockdown of the DNA glycosylases OGG1 and NEIL3 decreased NSC differentiation ability and resulted in decreased expression of both neuronal and astrocytic genes after mitogen withdrawal, as well as the stem cell marker Musashi-1. Furthermore, while cell survival remained unaffected, NEIL3 deficient cells displayed decreased cell proliferation rates along with an increase in HP1γ immunoreactivity, a sign of premature senescence. Our results suggest that DNA glycosylases play multiple roles in governing essential neural stem cell characteristics.

  4. Impact of Salinomycin on human cholangiocarcinoma: induction of apoptosis and impairment of tumor cell proliferation in vitro

    Directory of Open Access Journals (Sweden)

    Lieke Thorsten

    2012-10-01

    Full Text Available Abstract Background Cholangiocarcinoma (CC is a primary liver cancer with increasing incidence worldwide. Despite all efforts made in past years, prognosis remains to be poor. At least in part, this might be explained by a pronounced resistance of CC cells to undergo apoptosis. Thus, new therapeutic strategies are imperatively required. In this study we investigated the effect of Salinomycin, a polyether ionophore antibiotic, on CC cells as an appropriate agent to treat CC. Salinomycin was quite recently identified to induce apoptosis in cancer stem cells and to overcome apoptosis-resistance in several leukemia-cells and other cancer cell lines of different origin. Methods To delineate the effects of Salinomycin on CC, we established an in vitro cell culture model using three different human CC cell lines. After treatment apoptosis as well as migration and proliferation behavior was assessed and additional cell cycle analyses were performed by flowcytometry. Results By demonstrating Annexin V and TUNEL positivity of human CC cells, we provide evidence that Salinomycin reveals the capacity to break apoptosis-resistance in CC cells. Furthermore, we are able to demonstrate that the non-apoptotic cell fraction is characterized by sustainable impaired migration and proliferation. Cell cycle analyses revealed G2-phase accumulation of human CC cells after treatment with Salinomycin. Even though apoptosis is induced in two of three cell lines of CC cells, one cell line remained unaffected in regard of apoptosis but revealed as the other CC cells decreased proliferation and migration. Conclusion In this study, we are able to demonstrate that Salinomycin is an effective agent against previously resistant CC cells and might be a potential candidate for the treatment of CC in the future.

  5. Overexpression of IRS2 in isolated pancreatic islets causes proliferation and protects human β-cells from hyperglycemia-induced apoptosis

    International Nuclear Information System (INIS)

    Mohanty, S.; Spinas, G.A.; Maedler, K.; Zuellig, R.A.; Lehmann, R.; Donath, M.Y.; Trueb, T.; Niessen, M.

    2005-01-01

    Studies in vivo indicate that IRS2 plays an important role in maintaining functional β-cell mass. To investigate if IRS2 autonomously affects β-cells, we have studied proliferation, apoptosis, and β-cell function in isolated rat and human islets after overexpression of IRS2 or IRS1. We found that β-cell proliferation was significantly increased in rat islets overexpressing IRS2 while IRS1 was less effective. Moreover, proliferation of a β-cell line, INS-1, was decreased after repression of Irs2 expression using RNA oligonucleotides. Overexpression of IRS2 in human islets significantly decreased apoptosis of β-cells, induced by 33.3 mM D-glucose. However, IRS2 did not protect cultured rat islets against apoptosis in the presence of 0.5 mM palmitic acid. Overexpression of IRS2 in isolated rat islets significantly increased basal and D-glucose-stimulated insulin secretion as determined in perifusion experiments. Therefore, IRS2 is sufficient to induce proliferation in rat islets and to protect human β-cells from D-glucose-induced apoptosis. In addition, IRS2 can improve β-cell function. Our results indicate that IRS2 acts autonomously in β-cells in maintenance and expansion of functional β-cell mass in vivo

  6. THE EFFECT OF CURCUMIN ON SECRETORY ACTIVITY, PROLIFERATION AND APOPTOSIS OF THE PORCINE OVARIAN GRANULOSA CELLS

    Directory of Open Access Journals (Sweden)

    Attila Kádasi

    2012-08-01

    Full Text Available The aim of this in vitro study was to examine the effect of natural plant (Curcuma longa molecule curcumin on secretory activity, proliferation and apoptosis of porcine granulosa cells. The secretion of steroid hormones (progesterone, testosterone, accumulation of PCNA (marker of proliferation and bax (marker of apoptosis in granulosa cells of swine ovaries after curcumin treatment at the doses 0, 1, 10, 100 μg.mL-1 was determined by RIA and immunocytochemistry. It was observed that, addition of curcumin stimulated progesterone (at doses 1 and 10 μg.mL-1, but not 100 μg.mL-1 and testosterone at (100 μg.mL-1 but not 1 and 10 μg.mL-1 release. The number of cells contained PCNA was down-regulated by curcumin administration (at dose of 10 μg.mL-1, but not of 1 and 100 μg.mL-1. Bax expression was stimulated by curcumin at all doses added. Our results suggest a direct effect of curcumin on ovarian functions: steroidogenesis, proliferation and apoptosis. This could suggest antireproductive properties of curcumin in swine ovaries.

  7. Apoptosis and cell proliferation in the development of gastric carcinomas: associations with c-myc and p53 protein expression.

    Science.gov (United States)

    Ishii, Hideaki H; Gobé, Glenda C; Pan, Wenshen; Yoneyama, Juichi; Ebihara, Yoshiro

    2002-09-01

    Patients with gastric carcinomas have a poor prognosis and low survival rates. The aim of the present paper was to characterize cellular and molecular properties to provide insight into aspects of tumor progression in early compared with advanced gastric cancers. One hundred and nine graded gastric carcinomas (early or advanced stage, undifferentiated or differentiated type) with paired non-cancer tissue were studied to define the correlation between apoptosis (morphology, terminal deoxyribonucleotidyl transferase-mediated dUTP-digoxigenin nick end-labeling), cell proliferation (Ki-67 expression, morphology) and expression and localization of two proteins frequently having altered expression in cancers, namely p53 and c-myc. Overall, apoptosis was lower in early stage, differentiated and undifferentiated gastric carcinomas compared with advanced-stage cancers. Cell proliferation was comparatively high in all stages. There was a high level of p53 positivity in all stages. Only the early- and advanced-stage undifferentiated cancers that were p53 positive had a significantly higher level of apoptosis (P cancers that had either c-myc or p53-positivity. The results indicate that low apoptosis and high cell proliferation combine to drive gastric cancer development. The molecular controls for high cell proliferation of the early stage undifferentiated gastric cancers involve overexpression of both p53 and c-myc. Overexpression of p53 may also control cancer development in that its expression is associated with higher levels of apoptosis in early and late-stage undifferentiated, cancers. Copyright 2002 Blackwell Publishing Asia Pty Ltd

  8. miR-421 induces cell proliferation and apoptosis resistance in human nasopharyngeal carcinoma via downregulation of FOXO4

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    Chen, Liang [Neurosurgery Institute, Key Laboratory on Brain Function Repair and Regeneration of Guangdong, Zhujiang Hospital of Southern Medical University, Guangzhou 510282 (China); Department of Otolaryngology, Guangzhou General Hospital of PLA Guangzhou Command, Guangzhou 510010 (China); Tang, Yanping [Neurosurgery Institute, Key Laboratory on Brain Function Repair and Regeneration of Guangdong, Zhujiang Hospital of Southern Medical University, Guangzhou 510282 (China); Wang, Jian [Department of Otolaryngology, Guangzhou General Hospital of PLA Guangzhou Command, Guangzhou 510010 (China); Yan, Zhongjie [Affiliated Bayi Brain Hospital, The Military General Hospital of Beijing PLA,The Bayi Clinical Medical Institute of Southern Medical University, Beijing 100700 (China); Xu, Ruxiang, E-mail: RuxiangXu@yahoo.com [Affiliated Bayi Brain Hospital, The Military General Hospital of Beijing PLA,The Bayi Clinical Medical Institute of Southern Medical University, Beijing 100700 (China)

    2013-06-14

    Highlights: •miR-421 is upregulated in nasopharyngeal carcinoma. •miR-421 induces cell proliferation and apoptosis resistance. •FOXO4 is a direct and functional target of miR-421. -- Abstract: microRNAs have been demonstrated to play important roles in cancer development and progression. Hence, identifying functional microRNAs and better understanding of the underlying molecular mechanisms would provide new clues for the development of targeted cancer therapies. Herein, we reported that a microRNA, miR-421 played an oncogenic role in nasopharyngeal carcinoma. Upregulation of miR-421 induced, whereas inhibition of miR-421 repressed cell proliferation and apoptosis resistance. Furthermore, we found that upregulation of miR-421 inhibited forkhead box protein O4 (FOXO4) signaling pathway following downregulation of p21, p27, Bim and FASL expression by directly targeting FOXO4 3′UTR. Additionally, we demonstrated that FOXO4 expression is critical for miR-421-induced cell growth and apoptosis resistance. Taken together, our findings not only suggest that miR-421 promotes nasopharyngeal carcinoma cell proliferation and anti-apoptosis, but also uncover a novel regulatory mechanism for inactivation of FOXO4 in nasopharyngeal carcinoma.

  9. The role of Sep (O-phosphoserine) tRNA: Sec (selenocysteine) synthase (SEPSECS) in proliferation, apoptosis and hormone secretion of trophoblast cells.

    Science.gov (United States)

    Zhao, H-D; Zhang, W-G; Sun, M-N; Duan, Q-F; Li, F-L; Li, H

    2013-11-01

    To investigate whether Sep (O-phosphoserine) tRNA: Sec (selenocysteine) synthase (SEPSECS), which plays an essential role in the synthesis of selenoprotein, affects proliferation, apoptosis and hormone secretion of human trophoblast cells. Human trophoblast JEG-3 cells were divided into four groups: control group, SEPSECS silenced-expression group, empty vector group and SEPSECS over-expression group. Over-expression and silenced-expression were achieved by transfection with plasmid DNA or RNA oligonucleotide, respectively. 3-[4,5-dimethylthiazol-2-yl] -2,5-diphenyltetrazolium bromide (MTT) and colony formation assays were performed to investigate cell proliferation, while apoptosis was tested by annexin V-FITC, PI double staining and caspases-3 activation assays, enzyme-linked immunosorbent assay (ELISA) was used to determine the level of progesterone (PG) and human chorionic gonadotropin (hCG). SEPSECS silenced-expression clearly inhibited proliferation of JEG-3 cells (p < 0.05), significantly induced cell apoptosis (p < 0.01) and reduced the production of PG and hCG (p < 0.05). On the contrary, SEPSECS over-expression significantly promoted both cell proliferation (p < 0.01) and secretion of PG and hCG (p < 0.05). SEPSECS significantly affects proliferation, apoptosis and hormone secretion of human trophoblast cells, suggesting that a potential relationship exists among SEPSECS, cell proliferation, apoptosis and hormone production of human placental trophoblast cells. Furthermore, this may provide a clue to uncover the relationship between selenium and human placental in association with an emphasis on the importance of selenium adequacy during pregnancy. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Senescence gives insights into the morphogenetic evolution of anamniotes

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    Éric Villiard

    2017-06-01

    Full Text Available Senescence represents a mechanism to avoid undesired cell proliferation that plays a role in tumor suppression, wound healing and embryonic development. In order to gain insight on the evolution of senescence, we looked at its presence in developing axolotls (urodele amphibians and in zebrafish (teleost fish, which are both anamniotes. Our data indicate that cellular senescence is present in various developing structures in axolotls (pronephros, olfactory epithelium of nerve fascicles, lateral organs, gums and in zebrafish (epithelium of the yolk sac and in the lower part of the gut. Senescence was particularly associated with transient structures (pronephros in axolotls and yolk sac in zebrafish suggesting that it may play a role in the elimination of these tissues. Our data supports the notion that cellular senescence evolved early in vertebrate evolution to influence embryonic development.

  11. Senescence from glioma stem cell differentiation promotes tumor growth

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    Ouchi, Rie; Okabe, Sachiko; Migita, Toshiro; Nakano, Ichiro; Seimiya, Hiroyuki

    2016-01-01

    Glioblastoma (GBM) is a lethal brain tumor composed of heterogeneous cellular populations including glioma stem cells (GSCs) and differentiated non-stem glioma cells (NSGCs). While GSCs are involved in tumor initiation and propagation, NSGCs' role remains elusive. Here, we demonstrate that NSGCs undergo senescence and secrete pro-angiogenic proteins, boosting the GSC-derived tumor formation in vivo. We used a GSC model that maintains stemness in neurospheres, but loses the stemness and differentiates into NSGCs upon serum stimulation. These NSGCs downregulated telomerase, shortened telomeres, and eventually became senescent. The senescent NSGCs released pro-angiogenic proteins, including vascular endothelial growth factors and senescence-associated interleukins, such as IL-6 and IL-8. Conditioned medium from senescent NSGCs promoted proliferation of brain microvascular endothelial cells, and mixed implantation of GSCs and senescent NSGCs into mice enhanced the tumorigenic potential of GSCs. The senescent NSGCs seem to be clinically relevant, because both clinical samples and xenografts of GBM contained tumor cells that expressed the senescence markers. Our data suggest that senescent NSGCs promote malignant progression of GBM in part via paracrine effects of the secreted proteins. - Highlights: • Non-stem glioma cells (NSGCs) lose telomerase and eventually become senescent. • Senescent NSGCs secrete pro-angiogenic proteins, such as VEGFs, IL-6, and IL-8. • Senescent NSGCs enhance the growth of brain microvascular endothelial cells. • Senescent NSGCs enhance the tumorigenic potential of glioma stem cells in vivo.

  12. Senescence from glioma stem cell differentiation promotes tumor growth

    Energy Technology Data Exchange (ETDEWEB)

    Ouchi, Rie [Division of Molecular Biotherapy, Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550 (Japan); Laboratory of Molecular Target Therapy of Cancer, Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550 (Japan); Okabe, Sachiko; Migita, Toshiro [Division of Molecular Biotherapy, Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550 (Japan); Nakano, Ichiro [Department of Neurosurgery, Comprehensive Cancer Center, University of Alabama at Birmingham, 1824 6th Avenue South, Birmingham, AL 35233 (United States); Seimiya, Hiroyuki, E-mail: hseimiya@jfcr.or.jp [Division of Molecular Biotherapy, Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550 (Japan); Laboratory of Molecular Target Therapy of Cancer, Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550 (Japan)

    2016-02-05

    Glioblastoma (GBM) is a lethal brain tumor composed of heterogeneous cellular populations including glioma stem cells (GSCs) and differentiated non-stem glioma cells (NSGCs). While GSCs are involved in tumor initiation and propagation, NSGCs' role remains elusive. Here, we demonstrate that NSGCs undergo senescence and secrete pro-angiogenic proteins, boosting the GSC-derived tumor formation in vivo. We used a GSC model that maintains stemness in neurospheres, but loses the stemness and differentiates into NSGCs upon serum stimulation. These NSGCs downregulated telomerase, shortened telomeres, and eventually became senescent. The senescent NSGCs released pro-angiogenic proteins, including vascular endothelial growth factors and senescence-associated interleukins, such as IL-6 and IL-8. Conditioned medium from senescent NSGCs promoted proliferation of brain microvascular endothelial cells, and mixed implantation of GSCs and senescent NSGCs into mice enhanced the tumorigenic potential of GSCs. The senescent NSGCs seem to be clinically relevant, because both clinical samples and xenografts of GBM contained tumor cells that expressed the senescence markers. Our data suggest that senescent NSGCs promote malignant progression of GBM in part via paracrine effects of the secreted proteins. - Highlights: • Non-stem glioma cells (NSGCs) lose telomerase and eventually become senescent. • Senescent NSGCs secrete pro-angiogenic proteins, such as VEGFs, IL-6, and IL-8. • Senescent NSGCs enhance the growth of brain microvascular endothelial cells. • Senescent NSGCs enhance the tumorigenic potential of glioma stem cells in vivo.

  13. Effect of Docosahexaenoic Acid on Apoptosis and Proliferation in the Placenta: Preliminary Report

    Directory of Open Access Journals (Sweden)

    Ewa Wietrak

    2015-01-01

    Full Text Available Introduction. Observational studies confirm a higher incidence of preeclampsia in patients with low erythrocyte concentrations of omega-3 fatty acids. Observations point to an association of disorders of pregnancy, such as intrauterine growth restriction (IUGR and preeclampsia, with excessive apoptosis. One potential mechanism of action of docosahexaenoic acid (DHA promoting a reduction in the risk of pathological pregnancy may be by influencing these processes in the placenta. Materials and Methods. We investigated 28 pregnant women supplemented with a fish oil product containing 300 mg DHA starting from pregnancy week 20 until delivery (DHA group. The control group consisted of 50 women who did not receive such supplementation (control group. We determined the expression of Ki-67 and p21 as markers of proliferation and caspase 3 activity as a marker of apoptosis and DHA levels in umbilical cord blood. Results. Caspase 3 activity was significantly lower in the DHA group in comparison to the control group. Umbilical cord blood DHA concentration was higher in the DHA group. The expression of the proteins p21 and Ki-67 did not differ significantly between the groups. Conclusions. We observed an association between DHA supplementation and inhibition of placental apoptosis. We did not find an association between DHA and proliferation process in the placenta.

  14. Intermittent Stem Cell Cycling Balances Self-Renewal and Senescence of the C. elegans Germ Line.

    Directory of Open Access Journals (Sweden)

    Amanda Cinquin

    2016-04-01

    Full Text Available Self-renewing organs often experience a decline in function in the course of aging. It is unclear whether chronological age or external factors control this decline, or whether it is driven by stem cell self-renewal-for example, because cycling cells exhaust their replicative capacity and become senescent. Here we assay the relationship between stem cell cycling and senescence in the Caenorhabditis elegans reproductive system, defining this senescence as the progressive decline in "reproductive capacity," i.e. in the number of progeny that can be produced until cessation of reproduction. We show that stem cell cycling diminishes remaining reproductive capacity, at least in part through the DNA damage response. Paradoxically, gonads kept under conditions that preclude reproduction keep cycling and producing cells that undergo apoptosis or are laid as unfertilized gametes, thus squandering reproductive capacity. We show that continued activity is in fact beneficial inasmuch as gonads that are active when reproduction is initiated have more sustained early progeny production. Intriguingly, continued cycling is intermittent-gonads switch between active and dormant states-and in all likelihood stochastic. Other organs face tradeoffs whereby stem cell cycling has the beneficial effect of providing freshly-differentiated cells and the detrimental effect of increasing the likelihood of cancer or senescence; stochastic stem cell cycling may allow for a subset of cells to preserve proliferative potential in old age, which may implement a strategy to deal with uncertainty as to the total amount of proliferation to be undergone over an organism's lifespan.

  15. Stat3 Expression and Its Correlation with Proliferation and Apoptosis/Autophagy in Gliomas

    Directory of Open Access Journals (Sweden)

    Valentina Caldera

    2008-01-01

    Full Text Available Signal transducer and activator of transcription-3 (Stat3 was studied along with several steps of the PI3/Akt pathway in a series of 64 gliomas that included both malignant and low-grade tumors, using quantitative immunohistochemistry, Western blotting, and molecular biology techniques. The goal of the study was to investigate whether activated Stat3 (phospho-Stat3 levels correlated with cell proliferation, apoptosis, and autophagy. Stat3 and activated Akt (phospho-Akt expression increased with malignancy grade, but did not correlate with proliferation and survival within the category of glioblastomas. A correlation of Stat3 with Akt was found, indicating a regulation of the former by the PI3/Akt pathway, which, in turn, was in relation with EGFR amplification. Stat3 and Akt did not show any correlation with apoptosis, whereas they showed an inverse correlation with Beclin 1, a stimulator of autophagy, which was rarely positive in glioblastomas. Autophagy seems then to be inactivated in malignant gliomas.

  16. Oxidative stress inhibits adhesion and transendothelial migration, and induces apoptosis and senescence of induced pluripotent stem cells.

    Science.gov (United States)

    Wu, Yi; Zhang, Xueqing; Kang, Xueling; Li, Ning; Wang, Rong; Hu, Tiantian; Xiang, Meng; Wang, Xinhong; Yuan, Wenjun; Chen, Alex; Meng, Dan; Chen, Sifeng

    2013-09-01

    Oxidative stress caused by cellular accumulation of reactive oxygen species (ROS) is a major contributor to disease and cell death. However, how induced pluripotent stem cells (iPSC) respond to different levels of oxidative stress is largely unknown. Here, we investigated the effect of H2 O2 -induced oxidative stress on iPSC function in vitro. Mouse iPSC were treated with H2 O2 (25-100 μmol/L). IPSC adhesion, migration, viability, apoptosis and senescence were analysed. Expression of adhesion-related genes, stress defence genes, and osteoblast- and adipocyte-associated genes were determined by reverse transcription polymerase chain reaction. The present study found that H2 O2 (25-100 μmol/L) decreased iPSC adhesion to matrix proteins and endothelial cells, and downregulated gene expression levels of adhesion-related molecules, such as integrin alpha 7, cadherin 1 and 5, melanoma cell adhesion molecule, vascular cell adhesion molecule 1, and monocyte chemoattractant protein-1. H2 O2 (100 μmol/L) decreased iPSC viability and inhibited the capacity of iPSC migration and transendothelial migration. iPSC were sensitive to H2 O2 -induced G2/M arrest, senescence and apoptosis when exposed to H2 O2 at concentrations above 25 μmol/L. H2 O2 increased the expression of stress defence genes, including catalase, cytochrome B alpha, lactoperoxidase and thioredoxin domain containing 2. H2 O2 upregulated the expression of osteoblast- and adipocyte-associated genes in iPSC during their differentiation; however, short-term H2 O2 -induced oxidative stress did not affect the protein expression of the pluripotency markers, octamer-binding transcription factor 4 and sex-determining region Y-box 2. The present results suggest that iPSC are sensitive to H2 O2 toxicity, and inhibition of oxidative stress might be a strategy for improving their functions. © 2013 Wiley Publishing Asia Pty Ltd.

  17. Aryl hydrocarbon receptor-dependent regulation of miR-196a expression controls lung fibroblast apoptosis but not proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Hecht, Emelia [Department of Medicine, McGill University, Montreal, Quebec (Canada); Zago, Michela [Research Institute of the McGill University Health Centre, McGill University, Montreal, Quebec (Canada); Sarill, Miles [Department of Medicine, McGill University, Montreal, Quebec (Canada); Rico de Souza, Angela [Research Institute of the McGill University Health Centre, McGill University, Montreal, Quebec (Canada); Gomez, Alvin; Matthews, Jason [Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON (Canada); Hamid, Qutayba; Eidelman, David H. [Department of Medicine, McGill University, Montreal, Quebec (Canada); Research Institute of the McGill University Health Centre, McGill University, Montreal, Quebec (Canada); Baglole, Carolyn J., E-mail: Carolyn.baglole@McGill.ca [Department of Medicine, McGill University, Montreal, Quebec (Canada); Research Institute of the McGill University Health Centre, McGill University, Montreal, Quebec (Canada)

    2014-11-01

    The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor implicated in the regulation of apoptosis and proliferation. Although activation of the AhR by xenobiotics such as dioxin inhibits the cell cycle and control apoptosis, paradoxically, AhR expression also promotes cell proliferation and survival independent of exogenous ligands. The microRNA (miRNA) miR-196a has also emerged as a regulator of proliferation and apoptosis but a relationship between the AhR and miR-196a is not known. Therefore, we hypothesized that AhR-dependent regulation of endogenous miR-196a expression would promote cell survival and proliferation. Utilizing lung fibroblasts from AhR deficient (AhR{sup −/−}) and wild-type (AhR{sup +/+}) mice, we show that there is ligand-independent regulation of miRNA, including low miR-196a in AhR{sup −/−} cells. Validation by qRT-PCR revealed a significant decrease in basal expression of miR-196a in AhR{sup −/−} compared to AhR{sup +/+} cells. Exposure to AhR agonists benzo[a]pyrene (B[a]P) and FICZ as well as AhR antagonist CH-223191 decreased miR-196a expression in AhR{sup +/+} fibroblasts concomitant with decreased AhR protein levels. There was increased proliferation only in AhR{sup +/+} lung fibroblasts in response to serum, corresponding to a decrease in p27{sup KIP1} protein, a cyclin-dependent kinase inhibitor. Increasing the cellular levels of miR-196a had no effect on proliferation or expression of p27{sup KIP1} in AhR{sup −/−} fibroblasts but attenuated cigarette smoke-induced apoptosis. This study provides the first evidence that AhR expression is essential for the physiological regulation of cellular miRNA levels- including miR-196a. Future experiments designed to elucidate the functional relationship between the AhR and miR-196a may delineate additional novel ligand-independent roles for the AhR. - Highlights: • The AhR controls proliferation and apoptosis in lung cells. • The AhR regulates the

  18. Coupled Proliferation and Apoptosis Maintain the Rapid Turnover of Microglia in the Adult Brain

    Directory of Open Access Journals (Sweden)

    Katharine Askew

    2017-01-01

    Full Text Available Summary: Microglia play key roles in brain development, homeostasis, and function, and it is widely assumed that the adult population is long lived and maintained by self-renewal. However, the precise temporal and spatial dynamics of the microglial population are unknown. We show in mice and humans that the turnover of microglia is remarkably fast, allowing the whole population to be renewed several times during a lifetime. The number of microglial cells remains steady from late postnatal stages until aging and is maintained by the spatial and temporal coupling of proliferation and apoptosis, as shown by pulse-chase studies, chronic in vivo imaging of microglia, and the use of mouse models of dysregulated apoptosis. Our results reveal that the microglial population is constantly and rapidly remodeled, expanding our understanding of its role in the maintenance of brain homeostasis. : The mechanism or mechanisms underlying microglial homeostasis are unknown. Askew et al. show that microglia self-renewal is maintained by coupled proliferation and apoptosis, resulting in a stable microglia number over a mouse or human lifetime. Keywords: self-renewal, BrdU, CSF1R, CX3CR1, Macgreen, Vav-Bcl2, RNA-seq

  19. PTTG1 attenuates drug-induced cellular senescence.

    Directory of Open Access Journals (Sweden)

    Yunguang Tong

    Full Text Available As PTTG1 (pituitary tumor transforming gene abundance correlates with adverse outcomes in cancer treatment, we determined mechanisms underlying this observation by assessing the role of PTTG1 in regulating cell response to anti-neoplastic drugs. HCT116 cells devoid of PTTG1 (PTTG1(-/- exhibited enhanced drug sensitivity as assessed by measuring BrdU incorporation in vitro. Apoptosis, mitosis catastrophe or DNA damage were not detected, but features of senescence were observed using low doses of doxorubicin and TSA. The number of drug-induced PTTG1(-/- senescent cells increased ∼4 fold as compared to WT PTTG1-replete cells (p<0.001. p21, an important regulator of cell senescence, was induced ∼3 fold in HCT116 PTTG1(-/- cells upon doxorubicin or Trichostatin A treatment. Binding of Sp1, p53 and p300 to the p21 promoter was enhanced in PTTG1(-/- cells after treatment, suggesting transcriptional regulation of p21. p21 knock down abrogated the observed senescent effects of these drugs, indicating that PTTG1 likely suppresses p21 to regulate drug-induced senescence. PTTG1 also regulated SW620 colon cancer cells response to doxorubicin and TSA mediated by p21. Subcutaneously xenografted PTTG1(-/- HCT116 cells developed smaller tumors and exhibited enhanced responses to doxorubicin. PTTG1(-/- tumor tissue derived from excised tumors exhibited increased doxorubicin-induced senescence. As senescence is a determinant of cell responses to anti-neoplastic treatments, these findings suggest PTTG1 as a tumor cell marker to predict anti-neoplastic treatment outcomes.

  20. Induction of senescence and identification of differentially expressed genes in tomato in response to monoterpene.

    Directory of Open Access Journals (Sweden)

    Sumit Ghosh

    Full Text Available Monoterpenes, which are among the major components of plant essential oils, are known for their ecological roles as well for pharmaceutical properties. Geraniol, an acyclic monoterpene induces cell cycle arrest and apoptosis/senescence in various cancer cells and plants; however, the genes involved in the process and the underlying molecular mechanisms are not well understood. In this study, we demonstrate that treatment of tomato plants with geraniol results in induction of senescence due to a substantial alteration in transcriptome. We have identified several geraniol-responsive protein encoding genes in tomato using suppression subtractive hybridization (SSH approach. These genes comprise of various components of signal transduction, cellular metabolism, reactive oxygen species (ROS, ethylene signalling, apoptosis and DNA damage response. Upregulation of NADPH oxidase and antioxidant genes, and increase in ROS level after geraniol treatment point towards the involvement of ROS in geraniol-mediated senescence. The delayed onset of seedling death and induced expression of geraniol-responsive genes in geraniol-treated ethylene receptor mutant (Nr suggest that geraniol-mediated senescence involves both ethylene dependent and independent pathways. Moreover, expression analysis during tomato ripening revealed that geraniol-responsive genes are also associated with the natural organ senescence process.

  1. Induction of Senescence and Identification of Differentially Expressed Genes in Tomato in Response to Monoterpene

    Science.gov (United States)

    Kumar, Vinay; Kumar, Anil; Irfan, Mohammad; Chakraborty, Niranjan; Chakraborty, Subhra; Datta, Asis

    2013-01-01

    Monoterpenes, which are among the major components of plant essential oils, are known for their ecological roles as well for pharmaceutical properties. Geraniol, an acyclic monoterpene induces cell cycle arrest and apoptosis/senescence in various cancer cells and plants; however, the genes involved in the process and the underlying molecular mechanisms are not well understood. In this study, we demonstrate that treatment of tomato plants with geraniol results in induction of senescence due to a substantial alteration in transcriptome. We have identified several geraniol-responsive protein encoding genes in tomato using suppression subtractive hybridization (SSH) approach. These genes comprise of various components of signal transduction, cellular metabolism, reactive oxygen species (ROS), ethylene signalling, apoptosis and DNA damage response. Upregulation of NADPH oxidase and antioxidant genes, and increase in ROS level after geraniol treatment point towards the involvement of ROS in geraniol-mediated senescence. The delayed onset of seedling death and induced expression of geraniol-responsive genes in geraniol-treated ethylene receptor mutant (Nr) suggest that geraniol-mediated senescence involves both ethylene dependent and independent pathways. Moreover, expression analysis during tomato ripening revealed that geraniol-responsive genes are also associated with the natural organ senescence process. PMID:24098759

  2. MiR-155 promotes cell proliferation and inhibits apoptosis by PTEN signaling pathway in the psoriasis.

    Science.gov (United States)

    Xu, Longjiang; Leng, Hong; Shi, Xin; Ji, Jiang; Fu, Jinxiang; Leng, Hong

    2017-06-01

    MicroRNAs (miRNAs) have been demonstrated to contribute to malignant progression in psoriasis development. The purposes of the study was to evaluated the effects of miRNA-155 on cell proliferation, migration and apoptosis in psoriasis development via PTEN singaling pathway and identify its direct target protein. Quantitative real-time RT-PCR (qRT-PCR) was performed to examine the level of miR-155 in psoriasis cells, miR-155 was downregulated in a psoriasis cell line Hacat by transfected with small interfering RNA (siRNA), respectively. Cell survival was detected by the MTT assay and colony formation assay. Cell migration and invasion were measured via wound-healing assayand transwell assay. In addition, cell cycle and apoptosis about psoriasis cells was measured by flow cytometry. In this study, qRT-PCR assay showed that the expressions of miR-155 mRNA in psoriasis tissues were significantly higher than that in normal tissues. The assays about cell growth and proliferation showed that miR-155 knockdown led to a significant decrease in cell proliferation which was determined by MTT assay and colony formation assay compared to those of Lv-NC cells. Flow cytometry analysis showed that depletion of miR-155 could cause cell cycle change and the number of apoptotic cells was significantly increased in Lv-miR155 cells compared with control cells. In addition, the expression of several apoptosis-related factors were dramatically changed, such as PTEN, PIP 3 , AKT, p-AKT, Bax and Bcl-2. Our findings indicate that down-regulation of miR-155 significantly inhibits proliferation, migration, invasion and promotes apoptosis through PTEN singaling pathway in psoriasis cells. miR-155 might function as an oncogene miRNA in the progress of psoriasis. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  3. Dynamics of cell proliferation and apoptosis reflect different life strategies in hydrothermal vent and cold seep vestimentiferan tubeworms.

    Science.gov (United States)

    Pflugfelder, Bettina; Cary, S Craig; Bright, Monika

    2009-07-01

    Deep-sea vestimentiferan tubeworms, which live in symbiosis with bacteria, exhibit different life strategies according to their habitat. At unstable and relatively short-lived hydrothermal vents, they grow extremely fast, whereas their close relatives at stable and long-persisting cold seeps grow slowly and live up to 300 years. Growth and age differences are thought to occur because of ecological and physiological adaptations. However, the underlying mechanisms of cell proliferation and death, which are closely linked to homeostasis, growth, and longevity, are unknown. Here, we show by immunohistochemical and ultrastructural cell cycle analyses that cell proliferation activities of the two species studied are higher than in any other characterized invertebrate, being only comparable with tumor and wound-healing processes. The slow growth in Lamellibrachia luymesi from cold seeps results from balanced activities of proliferation and apoptosis in the epidermis. In contrast, Riftia pachyptila from hydrothermal vents grows fast because apoptosis is down-regulated in this tissue. The symbiont-housing organ, the trophosome, exhibits a complex cell cycle and terminal differentiation pattern in both species, and growth is regulated by proliferation. These mechanisms have similarities to the up- and down-regulation of proliferation or apoptosis in various types of tumor, although they occur in healthy animals in this study, thus providing significant insights into the underlying mechanisms of growth and longevity.

  4. Exploring cell apoptosis and senescence to understand and treat cancer: an interview with Scott Lowe

    Directory of Open Access Journals (Sweden)

    2015-11-01

    Full Text Available Scott W. Lowe is currently principal investigator at the Memorial Sloan-Kettering Cancer Center. After beginning his studies in chemical engineering, he decided to take another path and became fascinated by biochemistry, genetics and molecular biology, which ultimately led to an interest in human disease, particularly cancer. During his PhD at the Massachusetts Institute of Technology (MIT, Scott had the opportunity to benefit from the exceptional mentorship of Earl Ruley, David Housman and Tyler Jacks, and contributed to elucidating how the p53 (TP53 tumor suppressor gene limits oncogenic transformation and modulates the cytotoxic response to conventional chemotherapy. This important work earned him a fellowship from the Cold Spring Harbor Laboratory, which helped to launch his independent career. Scott is now a leading scientist in the cancer field and his work has helped to shed light on mechanisms of cell apoptosis and senescence to better understand and treat cancer. In this interview, he talks about this incredible scientific journey.

  5. Low Oxygen Modulates Multiple Signaling Pathways, Increasing Self-Renewal, While Decreasing Differentiation, Senescence, and Apoptosis in Stromal MIAMI Cells

    Science.gov (United States)

    Rios, Carmen; D'Ippolito, Gianluca; Curtis, Kevin M.; Delcroix, Gaëtan J.-R.; Gomez, Lourdes A.; El Hokayem, Jimmy; Rieger, Megan; Parrondo, Ricardo; de las Pozas, Alicia; Perez-Stable, Carlos; Howard, Guy A.

    2016-01-01

    Human bone marrow multipotent mesenchymal stromal cell (hMSC) number decreases with aging. Subpopulations of hMSCs can differentiate into cells found in bone, vasculature, cartilage, gut, and other tissues and participate in their repair. Maintaining throughout adult life such cell subpopulations should help prevent or delay the onset of age-related degenerative conditions. Low oxygen tension, the physiological environment in progenitor cell-rich regions of the bone marrow microarchitecture, stimulates the self-renewal of marrow-isolated adult multilineage inducible (MIAMI) cells and expression of Sox2, Nanog, Oct4a nuclear accumulation, Notch intracellular domain, notch target genes, neuronal transcriptional repressor element 1 (RE1)-silencing transcription factor (REST), and hypoxia-inducible factor-1 alpha (HIF-1α), and additionally, by decreasing the expression of (i) the proapoptotic proteins, apoptosis-inducing factor (AIF) and Bak, and (ii) senescence-associated p53 expression and β-galactosidase activity. Furthermore, low oxygen increases canonical Wnt pathway signaling coreceptor Lrp5 expression, and PI3K/Akt pathway activation. Lrp5 inhibition decreases self-renewal marker Sox2 mRNA, Oct4a nuclear accumulation, and cell numbers. Wortmannin-mediated PI3K/Akt pathway inhibition leads to increased osteoblastic differentiation at both low and high oxygen tension. We demonstrate that low oxygen stimulates a complex signaling network involving PI3K/Akt, Notch, and canonical Wnt pathways, which mediate the observed increase in nuclear Oct4a and REST, with simultaneous decrease in p53, AIF, and Bak. Collectively, these pathway activations contribute to increased self-renewal with concomitant decreased differentiation, cell cycle arrest, apoptosis, and/or senescence in MIAMI cells. Importantly, the PI3K/Akt pathway plays a central mechanistic role in the oxygen tension-regulated self-renewal versus osteoblastic differentiation of progenitor cells. PMID:27059084

  6. MAGE-A inhibits apoptosis in proliferating myeloma cells through repression of Bax and maintenance of survivin.

    Science.gov (United States)

    Nardiello, Tricia; Jungbluth, Achim A; Mei, Anna; Diliberto, Maurizio; Huang, Xiangao; Dabrowski, Ania; Andrade, Valéria C C; Wasserstrum, Rebecca; Ely, Scott; Niesvizky, Ruben; Pearse, Roger; Coleman, Morton; Jayabalan, David S; Bhardwaj, Nina; Old, Lloyd J; Chen-Kiang, Selina; Cho, Hearn Jay

    2011-07-01

    The type I Melanoma Antigen GEnes (MAGEs) are commonly expressed in cancers, fueling speculation that they may be therapeutic targets with oncogenic potential. They form complexes with RING domain proteins that have E3 ubiquitin ligase activity and promote p53 degradation. MAGE-A3 was detected in tumor specimens from patients with multiple myeloma and its expression correlated with higher frequencies of Ki-67(+) malignant cells. In this report, we examine the mechanistic role of MAGE-A in promoting survival of proliferating multiple myeloma cells. The impact of MAGE-A3 expression on survival and proliferation in vivo was examined by immunohistochemical analysis in an independent set of tumor specimens segregated into two groups: newly diagnosed, untreated patients and patients who had relapsed after chemotherapy. The mechanisms of MAGE-A3 activity were investigated in vitro by silencing its expression by short hairpin RNA interference in myeloma cell lines and primary cells and assessing the resultant effects on proliferation and apoptosis. MAGE-A3 was detected in a significantly higher percentage of relapsed patients compared with newly diagnosed, establishing a novel correlation with progression of disease. Silencing of MAGE-A showed that it was dispensable for cell cycling, but was required for survival of proliferating myeloma cells. Loss of MAGE-A led to apoptosis mediated by p53-dependent activation of proapoptotic Bax expression and by reduction of survivin expression through both p53-dependent and -independent mechanisms. These data support a role for MAGE-A in the pathogenesis and progression of multiple myeloma by inhibiting apoptosis in proliferating myeloma cells through two novel mechanisms.

  7. WSB1 overcomes oncogene-induced senescence by targeting ATM for degradation

    Science.gov (United States)

    Kim, Jung Jin; Lee, Seung Baek; Yi, Sang-Yeop; Han, Sang-Ah; Kim, Sun-Hyun; Lee, Jong-Min; Tong, Seo-Yun; Yin, Ping; Gao, Bowen; Zhang, Jun; Lou, Zhenkun

    2017-01-01

    Oncogene-induced senescence (OIS) or apoptosis through the DNA-damage response is an important barrier of tumorigenesis. Overcoming this barrier leads to abnormal cell proliferation, genomic instability, and cellular transformation, and finally allows cancers to develop. However, it remains unclear how the OIS barrier is overcome. Here, we show that the E3 ubiquitin ligase WD repeat and SOCS box-containing protein 1 (WSB1) plays a role in overcoming OIS. WSB1 expression in primary cells helps the bypass of OIS, leading to abnormal proliferation and cellular transformation. Mechanistically, WSB1 promotes ATM ubiquitination, resulting in ATM degradation and the escape from OIS. Furthermore, we identify CDKs as the upstream kinase of WSB1. CDK-mediated phosphorylation activates WSB1 by promoting its monomerization. In human cancer tissue and in vitro models, WSB1-induced ATM degradation is an early event during tumorigenic progression. We suggest that WSB1 is one of the key players of early oncogenic events through ATM degradation and destruction of the tumorigenesis barrier. Our work establishes an important mechanism of cancer development and progression in premalignant lesions. PMID:27958289

  8. The DNA glycosylases OGG1 and NEIL3 influence differentiation potential, proliferation, and senescence-associated signs in neural stem cells

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    Reis, Amilcar [Linnaeus Center in Developmental Biology for Regenerative Medicine (DBRM), Department of Neuroscience, Karolinska Institutet, SE 17177 Stockholm (Sweden); Hermanson, Ola, E-mail: ola.hermanson@ki.se [Linnaeus Center in Developmental Biology for Regenerative Medicine (DBRM), Department of Neuroscience, Karolinska Institutet, SE 17177 Stockholm (Sweden)

    2012-07-13

    Highlights: Black-Right-Pointing-Pointer DNA glycosylases OGG1 and NEIL3 are required for neural stem cell state. Black-Right-Pointing-Pointer No effect on cell viability by OGG1 or NEIL3 knockdown in neural stem cells. Black-Right-Pointing-Pointer OGG1 or NEIL3 RNA knockdown result in decreased proliferation and differentiation. Black-Right-Pointing-Pointer Increased HP1{gamma} immunoreactivity after NEIL3 knockdown suggests premature senescence. -- Abstract: Embryonic neural stem cells (NSCs) exhibit self-renewal and multipotency as intrinsic characteristics that are key parameters for proper brain development. When cells are challenged by oxidative stress agents the resulting DNA lesions are repaired by DNA glycosylases through the base excision repair (BER) pathway as a means to maintain the fidelity of the genome, and thus, proper cellular characteristics. The functional roles for DNA glycosylases in NSCs have however remained largely unexplored. Here we demonstrate that RNA knockdown of the DNA glycosylases OGG1 and NEIL3 decreased NSC differentiation ability and resulted in decreased expression of both neuronal and astrocytic genes after mitogen withdrawal, as well as the stem cell marker Musashi-1. Furthermore, while cell survival remained unaffected, NEIL3 deficient cells displayed decreased cell proliferation rates along with an increase in HP1{gamma} immunoreactivity, a sign of premature senescence. Our results suggest that DNA glycosylases play multiple roles in governing essential neural stem cell characteristics.

  9. Transcriptional Control of Vascular Smooth Muscle Cell Proliferation by Peroxisome Proliferator-Activated Receptor-γ: Therapeutic Implications for Cardiovascular Diseases

    Directory of Open Access Journals (Sweden)

    Florence Gizard

    2008-01-01

    Full Text Available Proliferation of vascular smooth muscle cells (SMCs is a critical process for the development of atherosclerosis and complications of procedures used to treat atherosclerotic diseases, including postangioplasty restenosis, vein graft failure, and transplant vasculopathy. Peroxisome proliferator-activated receptor (PPAR γ is a member of the nuclear hormone receptor superfamily and the molecular target for the thiazolidinediones (TZD, used clinically to treat insulin resistance in patients with type 2 diabetes. In addition to their efficacy to improve insulin sensitivity, TZD exert a broad spectrum of pleiotropic beneficial effects on vascular gene expression programs. In SMCs, PPARγ is prominently upregulated during neointima formation and suppresses the proliferative response to injury of the arterial wall. Among the molecular target genes regulated by PPARγ in SMCs are genes encoding proteins involved in the regulation of cell-cycle progression, cellular senescence, and apoptosis. This inhibition of SMC proliferation is likely to contribute to the prevention of atherosclerosis and postangioplasty restenosis observed in animal models and proof-of-concept clinical studies. This review will summarize the transcriptional target genes regulated by PPARγ in SMCs and outline the therapeutic implications of PPARγ activation for the treatment and prevention of atherosclerosis and its complications.

  10. Effects of anti-CD40 mAb on inducing malignant B cells proliferation arrest and apoptosis and its mechanism

    International Nuclear Information System (INIS)

    Tang Lin; Zhuang Yumei; Zhou Zhaohua; Yu Gehua; Pan Jianzhong; Zhang Xueguang

    2002-01-01

    Objective: To study the expression of CD 40 molecule and the biological effects mediated by CD 40 molecules on malignant B cells. Methods: Agonistic anti-human CD 40 monoclonal antibody (clone 5C11) was added to cell culture system. Cell counting, PI staining, Annexin-V staining and flow cytometric analysis were used to study the behavior of malignant B cell lines after treatment with mAb clone 5C11. Results: 5C11 induced homotypic aggregation and proliferation arrest and mediated apoptosis in multiple myeloma cell line XG2 that expressed CD 40 strongly; 5C11 induced B lymphoma cell line Daudi homotypic aggregation and proliferation arrest and apoptosis, the apoptosis of XG2 and Daudi by CD40 activation was not mediated by TNF. Conclusion: Agonistic anti-CD 40 mAb 5C11 can inhibit the proliferation of malignant B cells by inducing them to die apoplectically

  11. Effects and underlying mechanisms of irisin on the proliferation and apoptosis of pancreatic β cells.

    Directory of Open Access Journals (Sweden)

    Shiwei Liu

    Full Text Available Pancreatic β cell dysfunction and reduction due to glucose toxicity play a crucial role in the development of type 2 diabetes mellitus (T2DM. Irisin, a novel exercise-induced myokine, reduces obesity, improves insulin resistance and lowers blood glucose by promoting the browning of white adipose tissue, thereby enhancing thermogenesis and increasing energy expenditure. Recent studies have reported that irisin promotes cell proliferation and protects cells from apoptosis. However, the effects of irisin on pancreatic β cells are unknown. Thus, the aim of this study was to investigate the effects and the potential underlying mechanisms of irisin on pancreatic β cell proliferation and apoptosis induced by high glucose. Both in vitro (INS-1 cells and in vivo (a T2DM rat model experiments were conducted. Irisin significantly increased the proliferation of INS-1 cells, with the most significant effect observed at 24 h with 100 ng/ml irisin. Irisin also promoted INS-1 cell proliferation via the ERK and p38 MAPK signaling pathways, protected the cells from high-glucose-induced apoptosis by regulating the expression of caspases, Bad, Bax, Bcl-2 and Bcl-xl, and improved pancreatic β cell function. Irisin significantly reduced the body weight and blood glucose values and increased the serum insulin levels of the diabetic rats. An oral glucose tolerance test (OGTT indicated that irisin also improved the glucose tolerance of T2DM rats. Together, these findings suggest that irisin may have applications in the prevention and treatment of T2DM because of its protective effect on the secretion of pancreatic β cells.

  12. miR-130b targets NKD2 and regulates the Wnt signaling to promote proliferation and inhibit apoptosis in osteosarcoma cells

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    Li, Zhi [Department of Human Anatomy and Histoembryology, College of Basic Medical Sciences, Jilin University (China); Li, Youjun, E-mail: liyoujunn@126.com [Department of Human Anatomy and Histoembryology, College of Basic Medical Sciences, Jilin University (China); Wang, Nan; Yang, Lifeng; Zhao, Wei; Zeng, Xiandong [Central Hospital Affiliated to Shenyang Medical College (China)

    2016-03-18

    miR-130b was significantly up-regulated in osteosarcoma (OS) cells. Naked cuticle homolog 2 (NKD2) inhibited tumor growth and metastasis in OS by suppressing Wnt signaling. We used three miRNA target analysis tools to identify potential targets of miR-130b, and found that NKD2 is a potential target of miR-130b. Based on these findings, we hypothesize that miR-130b might target NKD2 and regulate the Wnt signaling to promote OS growth. We detected the expression of miR-130b and NKD2 mRNA and protein by quantitative Real-Time PCR (qRT-PCR) and western blot assays, respectively, and found up-regulation of miR-130b and down-regulation of NKD2 mRNA and protein exist in OS cell lines. MTT and flow cytometry assays showed that miR-130b inhibitors inhibit proliferation and promote apoptosis in OS cells. Furthermore, we showed that NKD2 is a direct target of miR-130b, and miR-130b regulated proliferation and apoptosis of OS cells by targeting NKD2. We further investigated whether miR-130b and NKD2 regulate OS cell proliferation and apoptosis by inhibiting Wnt signaling, and the results confirmed our speculation that miR-130b targets NKD2 and regulates the Wnt signaling to promote proliferation and inhibit apoptosis of OS cells. These findings will offer new clues for OS development and progression, and novel potential therapeutic targets for OS. - Highlights: • miR-130b is up-regulated and NKD2 is down-regulated in osteosarcoma cell lines. • Down-regulation of miR-130b inhibits proliferation of osteosarcoma cells. • Down-regulation of miR-130b promotes apoptosis of osteosarcoma cells. • miR-130b directly targets NKD2. • NKD2 regulates OS cell proliferation and apoptosis by inhibiting the Wnt signaling.

  13. miR-130b targets NKD2 and regulates the Wnt signaling to promote proliferation and inhibit apoptosis in osteosarcoma cells

    International Nuclear Information System (INIS)

    Li, Zhi; Li, Youjun; Wang, Nan; Yang, Lifeng; Zhao, Wei; Zeng, Xiandong

    2016-01-01

    miR-130b was significantly up-regulated in osteosarcoma (OS) cells. Naked cuticle homolog 2 (NKD2) inhibited tumor growth and metastasis in OS by suppressing Wnt signaling. We used three miRNA target analysis tools to identify potential targets of miR-130b, and found that NKD2 is a potential target of miR-130b. Based on these findings, we hypothesize that miR-130b might target NKD2 and regulate the Wnt signaling to promote OS growth. We detected the expression of miR-130b and NKD2 mRNA and protein by quantitative Real-Time PCR (qRT-PCR) and western blot assays, respectively, and found up-regulation of miR-130b and down-regulation of NKD2 mRNA and protein exist in OS cell lines. MTT and flow cytometry assays showed that miR-130b inhibitors inhibit proliferation and promote apoptosis in OS cells. Furthermore, we showed that NKD2 is a direct target of miR-130b, and miR-130b regulated proliferation and apoptosis of OS cells by targeting NKD2. We further investigated whether miR-130b and NKD2 regulate OS cell proliferation and apoptosis by inhibiting Wnt signaling, and the results confirmed our speculation that miR-130b targets NKD2 and regulates the Wnt signaling to promote proliferation and inhibit apoptosis of OS cells. These findings will offer new clues for OS development and progression, and novel potential therapeutic targets for OS. - Highlights: • miR-130b is up-regulated and NKD2 is down-regulated in osteosarcoma cell lines. • Down-regulation of miR-130b inhibits proliferation of osteosarcoma cells. • Down-regulation of miR-130b promotes apoptosis of osteosarcoma cells. • miR-130b directly targets NKD2. • NKD2 regulates OS cell proliferation and apoptosis by inhibiting the Wnt signaling.

  14. Implication of p53-dependent cellular senescence related gene, TARSH in tumor suppression

    International Nuclear Information System (INIS)

    Wakoh, Takeshi; Uekawa, Natsuko; Terauchi, Kunihiko; Sugimoto, Masataka; Ishigami, Akihito; Shimada, Jun-ichi; Maruyama, Mitsuo

    2009-01-01

    A novel target of NESH-SH3 (TARSH) was identified as a cellular senescence related gene in mouse embryonic fibroblasts (MEFs) replicative senescence, the expression of which has been suppressed in primary clinical lung cancer specimens. However, the molecular mechanism underlying the regulation of TARSH involved in pulmonary tumorigenesis remains unclear. Here we demonstrate that the reduction of TARSH gene expression by short hairpin RNA (shRNA) system robustly inhibited the MEFs proliferation with increase in senescence-associated β-galactosidase (SA-β-gal) activity. Using p53 -/- MEFs, we further suggest that this growth arrest by loss of TARSH is evoked by p53-dependent p21 Cip1 accumulation. Moreover, we also reveal that TARSH reduction induces multicentrosome in MEFs, which is linked in chromosome instability and tumor development. These results suggest that TARSH plays an important role in proliferation of replicative senescence and may serve as a trigger of tumor development.

  15. Effects and mechanism of GA-13315 on the proliferation and apoptosis of KB cells in oral cancer.

    Science.gov (United States)

    Shen, Shan; Tang, Jingxia

    2017-08-01

    The present study describes the effects and mechanism of GA-13315 on the proliferation and apoptosis of KB cells in oral cancer. Oral cancer is twice as common in men than women. More than 90% of oral cancers in men and 85% in women are linked to lifestyle and environmental factors. PPP2R2B methylation may be associated with survival and prognosis in patients with gliomas. In tumor cell proliferation and apoptosis, the mechanism of PPP2R2B remains unclear. In the present study, we found that PPP2R2B expression of H1299 cells is significantly decreased after being treated by GA-13315. KB cells were isolated from patients with oral cancer and treated with GA-13315 (5 µM). Cells without GA-13315 treatment served as the control group. An MTT experiment was performed to detect the post-treatment cell growth between the groups. A flow cytometry was used to detect cell apoptosis. Western blot analysis and quantitative polymerase chain reaction methods were used for detecting the expression of PPP2R2B. Compared with the control group, the cell proliferation of the treatment group slowed after being treated with GA-13315. The difference was statistically significant (Poral cancer were weakened after being treated by GA-13315. GA-13315 can accelerate the apoptosis of oral cancer cells and presents a dose correlation. The biological effect is exerted through the decrease of PPP2R2B.

  16. Molecular genetic approaches to the study of cellular senescence.

    Science.gov (United States)

    Goletz, T J; Smith, J R; Pereira-Smith, O M

    1994-01-01

    Cellular senescence is an inability of cells to synthesize DNA and divide, which results in a terminal loss of proliferation despite the maintenance of basic metabolic processes. Senescence has been proposed as a model for the study of aging at the cellular level, and the basis for this model system and its features have been summarized. Although strong experimental evidence exists to support the hypothesis that cellular senescence is a dominant active process, the mechanisms responsible for this phenomenon remain a mystery. Investigators have taken several approaches to gain a better understanding of senescence. Several groups have documented the differences between young and senescent cells, and others have identified changes that occur during the course of a cell's in vitro life span. Using molecular and biochemical approaches, important changes in gene expression and function of cell-cycle-associated products have been identified. The active production of an inhibitor of DNA synthesis has been demonstrated. This may represent the final step in a cascade of events governing senescence. The study of immortal cells which have escaped senescence has also provided useful information, particularly with regard to the genes governing the senescence program. These studies have identified four complementation groups for indefinite division, which suggests that there are at least four genes or gene pathways in the senescence program. Through the use of microcell-mediated chromosome transfer, chromosomes encoding senescence genes have been identified; efforts to clone these genes are ongoing.(ABSTRACT TRUNCATED AT 250 WORDS)

  17. Mechanical stretch modulates microRNA 21 expression, participating in proliferation and apoptosis in cultured human aortic smooth muscle cells.

    Directory of Open Access Journals (Sweden)

    Jian tao Song

    Full Text Available OBJECTIVES: Stretch affects vascular smooth muscle cell proliferation and apoptosis, and several responsible genes have been proposed. We tested whether the expression of microRNA 21 (miR-21 is modulated by stretch and is involved in stretch-induced proliferation and apoptosis of human aortic smooth muscle cells (HASMCs. METHODS AND RESULTS: RT-PCR revealed that elevated stretch (16% elongation, 1 Hz increased miR-21 expression in cultured HASMCs, and moderate stretch (10% elongation, 1 Hz decreased the expression. BrdU incorporation assay and cell counting showed miR-21 involved in the proliferation of HASMCs mediated by stretch, likely by regulating the expression of p27 and phosphorylated retinoblastoma protein (p-Rb. FACS analysis revealed that the complex of miR-21 and programmed cell death protein 4 (PDCD4 participated in regulating apoptosis with stretch. Stretch increased the expression of primary miR-21 and pre-miR-21 in HASMCs. Electrophoretic mobility shift assay (EMSA demonstrated that stretch increased NF-κB and AP-1 activities in HASMCs, and blockade of AP-1 activity by c-jun siRNA significantly suppressed stretch-induced miR-21 expression. CONCLUSIONS: Cyclic stretch modulates miR-21 expression in cultured HASMCs, and miR-21 plays important roles in regulating proliferation and apoptosis mediated by stretch. Stretch upregulates miR-21 expression at least in part at the transcription level and AP-1 is essential for stretch-induced miR-21 expression.

  18. Effects of Raloxifene on the Proliferation and Apoptosis of Human Aortic Valve Interstitial Cells

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    Zhimin Fu

    2016-01-01

    Full Text Available We aimed to explore the effects of raloxifene (RAL on the proliferation and apoptosis of human aortic valve interstitial cells (AVICs. Different concentrations of RAL were used to act on AVICs. MTS kit is used to test the effects of different concentrations of RAL on the proliferation of AVICs. Cell cycle and apoptosis test used flow cytometry after seven-day treatment. The relative expression levels of caspase-3 and caspase-8 are tested with RT-qPCR and Western blot. The results of MTS testing revealed that the absorbance value (OD value of the cells in the concentration groups of 10 and 100 nmol/L RAL at a wavelength of 490 nm at five, seven, and nine days significantly decreased compared with that in the control group. Meanwhile, the results of flow cytometry of the cells collected after seven days showed that the ratio of the S stage and the cell apoptosis rate of AVICs can be significantly reduced by RAL in the concentration groups of 10 and 100 nmol/L. The mRNA and protein expressions of caspase-3 and caspase-8 were significantly decreased compared with those in the control group. This study laid the foundation for further treatment of aortic valve disease by using RAL.

  19. Experimental study of the effect of 103Pd on the proliferation and apoptosis of vascular smooth muscle cells

    International Nuclear Information System (INIS)

    Luo Quanyong; Zhu Jun; Chen Libo; Lu Hankui; Zhu Ruisen

    2002-01-01

    Objective: To investigate the ability of γ emitting radionuclide 103 Pd to inhibit the vascular smooth muscle cell (SMC) proliferation and to induce its apoptosis in vitro. Methods: 103 Pd solution was added to the culture medium to irradiate SMCs for 72 h and non-radioactive Pd solution was added as control. 3 H-TdR incorporation test was used to detect the effect of 103 Pd on the proliferation of SMCs. Flow cytometer was used to detect the apoptotic SMCs. Results: The results showed that inhibition of SMC proliferation was evident and the effects were dose-dependant. Inhibition rate of SMC proliferation by 1.85 MBq 103 Pd was 2.3% , which was not significant. The inhibition rate increased from 41.6% to 91.2% as the dose of 103 Pd increased from 7.4 to 37.0 MBq, and the proliferation of SMCs was repressed significantly then. The apoptosis rate was extremely low (less than 4.0% ) with the 103 pd dose escalating from 1.85 to 37.0 MBq. Conclusions: This study suggests that proliferation of SMCs can be repressed effectively in vitro by 103 pd. 103 Pd can be used to inhibit the neointimal proliferation. 103 Pd radioactive stent implantation can be employed as a possible novel means to prevent restenosis

  20. Effects of DCK knockdown on proliferation, apoptosis and tumorigenicity in vivo of cervical cancer HeLa cells.

    Science.gov (United States)

    Shang, Q-Y; Wu, C-S; Gao, H-R

    2017-09-01

    The present study explored the effect that deoxycytidine kinase (DCK) knockdown had on proliferation, apoptosis and tumorigenicity in vivo of cervical cancer HeLa cells. Human cervical cancer HeLa cells that had received no prior treatment were selected from the HeLa group. The HeLa-negative control (NC) group consisted of cells that had undergone an empty vector treatment, and finally the HeLa-short hairpin RNA (shRNA) group included cells that were treated by means of shRNA-DCK expression. DCK expressions were evaluated by quantitative real-time polymerase chain reaction in addition to western blotting assays. Cell proliferation was estimated using the Cell Counting Kit-8 (CCK-8) assay and cell cycle progression. Cell apoptosis was determined by flow cytometry. BALB/c nude mice (n=24) were selected to establish transplanted tumor models, with gross tumor volume measured every 3 days. The results in vitro were as follows: compared with the HeLa group, the HeLa-shRNA group exhibited downregulation of DCK expression and inhibition of cell proliferation at 48, 72 and 96 h. Additionally, more cells in the HeLa-shRNA group were arrested in G0/G1 stage and less in S and G2/M stages, as well as in promotion of cell apoptosis. In vivo results are as follows: when comparing the HeLa and HeLa-NC groups, the gross tumor volume of the transplanted tumor in nude mice in the HeLa-shRNA group was found to have decreased in 13, 16, 19 and 22 days. Based on these findings, our study suggests that DCK knockdown facilitates apoptosis while inhibiting proliferation and tumorigenicity in vivo of cervical cancer HeLa cells.

  1. The thorny path linking cellular senescence to organismalaging

    Energy Technology Data Exchange (ETDEWEB)

    Patil, Christopher K.; Mian, Saira; Campisi, Judith

    2005-08-09

    Half a century is fast approaching since Hayflick and colleagues formally described the limited ability of normal human cells to proliferate in culture (Hayflick and Moorhead, 1961). This finding--that normal somatic cells, in contrast to cancer cells, cannot divide indefinitely--challenged the prevailing idea that cells from mortal multicellular organisms were intrinsically ''immortal'' (Carrell, 1912). It also spawned two hypotheses, essential elements of which persist today. The first held that the restricted proliferation of normal cells, now termed cellular senescence, suppresses cancer (Hayflick, 1965; Sager, 1991; Campisi, 2001). The second hypothesis, as explained in the article by Lorenzini et al., suggested that the limited proliferation of cells in culture recapitulated aspects of organismal aging (Hayflick, 1965; Martin, 1993). How well have these hypotheses weathered the ensuing decades? Before answering this question, we first consider current insights into the causes and consequences of cellular senescence. Like Lorenzini et al., we limit our discussion to mammals. We also focus on fibroblasts, the cell type studied by Lorenzini et al., but consider other types as well. We suggest that replicative capacity in culture is not a straightforward assessment, and that it correlates poorly with both longevity and body mass. We speculate this is due to the malleable and variable nature of replicative capacity, which renders it an indirect metric of qualitative and quantitative differences among cells to undergo senescence, a response that directly alters cellular phenotype and might indirectly alter tissue structure and function.

  2. Up-regulation of hypoxia inducible factor-1α by cobalt chloride correlates with proliferation and apoptosis in PC-2 cells

    Directory of Open Access Journals (Sweden)

    Dai Zhi-Jun

    2012-03-01

    Full Text Available Abstract Background The exact mechanism of the effects of hypoxia on the proliferation and apoptosis in carcinoma cells is still conflicting. This study investigated the variation of hypoxia-inducible factor-1α(HIF-1α expression and the apoptosis effect of hypoxia stimulated by cobalt chloride (CoCl2 in pancreatic cancer PC-2 cells. Methods PC-2 cells were cultured with different concentration (50-200 μmol/L of CoCl2 after 24-120 hours to simulate hypoxia in vitro. The proliferation of PC-2 cells was examined by MTT assay. The cellular morphology of PC-2 cells were observed by light inverted microscope and transmission electron microscope(EM. The expression of HIF-1α on mRNA and protein level was measured by semi-quantitive RT-PCR and Western blot analysis. Apoptosis of PC-2 cells were demonstrated by flow cytometry with Annexin V-FITC/PI double staining. Results MTT assay showed that the proliferation of PC-2 cells were stimulated in the first 72 h, while after treated over 72 h, a dose- dependent inhibition of cell growth could be observed. By using transmission electron microscope, swollen chondrosomes, accumulated chromatin under the nuclear membrane and apoptosis bodies were observed. Flow cytometer(FCM analysis showed the apoptosis rate was correlated with the dosage of CoCl2. RT-PCR and Western blot analysis indicated that hypoxia could up-regulate the expression of HIF-1α on both mRNA and protein levels. Conclusion Hypoxic microenvironment stimulated by CoCl2 could effectively induce apoptosis and influence cell proliferation in PC-2 cells, the mechanism could be related to up-expression of HIF-1α.

  3. Parental High-Fat Diet Promotes Inflammatory and Senescence-Related Changes in Prostate

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    Kulbhushan Tikoo

    2017-01-01

    Full Text Available Background. Obesity and dietary habits are associated with increased incidences of aging-related prostatic diseases. The present study was aimed to investigate transgenerational effects of chronic high-fat diet (HFD feeding on inflammation and senescence-related changes in prostate. Methods. Sprague-Dawley rats were kept on either normal or HFD one. Senescence-associated β-galactosidase (SA β-gal activity, inflammation, and cellular proliferation were determined in the prostate. Results. Increased SA β-gal activity, expression of p53, and cell proliferation marker PCNA were observed in ventral prostate of HFD-fed rats. Immunostaining for p53 and PCNA revealed that the p53 immunopositive cells were primarily in stroma while PCNA immunopositive cells were epithelial cells. An increase in expression of cycloxygenase-2 (COX-2 and phosphorylation of nuclear factor-kappa B (NF-kB was observed in prostate of weaning pups HFD-fed parents. However, in adult pups, irrespective of dietary habit, a significant increase in the expression of COX-2, PCNA, phosphorylation of NF-kB, infiltration of inflammatory cells, and SA β-gal activity was observed. Conclusions. Present investigation reports that HFD feeding promotes accumulation of p53 expressing cells, proliferation of epithelial cells, and senescence-related changes in prostate. Further, parental HFD-feeding upholds inflammatory, proliferative, and senescence-related changes in prostate of pups.

  4. NF-κB is involved in the LPS-mediated proliferation and apoptosis of MAC-T epithelial cells as part of the subacute ruminal acidosis response in cows.

    Science.gov (United States)

    Fan, Wen-Jie; Li, He-Ping; Zhu, He-Shui; Sui, Shi-Ping; Chen, Pei-Ge; Deng, Yue; Sui, Tong-Ming; Wang, Yue-Ying

    2016-11-01

    To determine the effect of NF-κB on cell proliferation and apoptosis, we investigate the expression of inflammation and apoptosis-related factors in the bovine mammary epithelial cell line, MAC-T. MAC-T cells were cultured in vitro and MTT and LDH assays used to determine the effects of lipopolysaccharide (LPS) on proliferation and cytotoxicity respectively. RT-PCR and western blotting were used to evaluate the effect of LPS and NF-κB inhibition [pyrrolidine dithiocarbamate (PDTC) treatment] on the expression of inflammation and apoptosis-related factors. LPS significantly inhibited MAC-T cell proliferation in a dose- and time-dependent manner. Furthermore, LPS promoted apoptosis while the NF-кB inhibitor PDTC attenuated this effect. After LPS treatment, the NF-кB signaling pathway was activated, and the expression of inflammation and apoptosis-related factors increased. When PDTC blocked NF-кB signaling, the expression of inflammation and apoptosis-related factors were decreased in MAC-T cells. LPS activates the TLR4/NF-κB signaling pathway, inhibits proliferation and promotes apoptosis in MAC-T cells. NF-кB inhibition attenuates MAC-T cell apoptosis and TLR4/NF-κB signaling pathway. NF-кB inhibitor alleviating MAC-T cell apoptosis is presumably modulated by NF-кB.

  5. Study on the effects of gradient mechanical pressures on the proliferation, apoptosis, chondrogenesis and hypertrophy of mandibular condylar chondrocytes in vitro.

    Science.gov (United States)

    Li, Hui; Huang, Linjian; Xie, Qianyang; Cai, Xieyi; Yang, Chi; Wang, Shaoyi; Zhang, Min

    2017-01-01

    To investigate the effects of gradient mechanical pressure on chondrocyte proliferation, apoptosis, and the expression of markers of chondrogenesis and chondrocyte hypertrophy. Mandibular condylar chondrocytes from 5 rabbits were cultured in vitro, and pressed with static pressures of 50kPa, 100kPa, 150kPa and 200kPa for 3h, respectively. The chondrocytes cultured without pressure (0kPa) were used as control. Cell proliferation, apoptosis, and the expression of aggrecan (AGG), collagen II (COL2), collagen X (COL10), alkaline phosphatase (ALP) were investigated. Ultrastructures of the pressurized chondrocytes under transmission electron microscopy (TEM) were observed. Chondrocyte proliferation increased at 100kPa and decreased at 200kPa. Chondrocyte apoptosis increased with peak pressure at 200kPa in a dose-dependent manner. Chondrocyte necrosis increased at 200kPa. The expression of AGG increased at 200kPa. The expression of COL2 decreased at 50kPa and increased at 150kPa. The expression of COL10 and ALP increased at 150kPa. Ultrastructure of the pressurized chondrocytes under TEM showed: at 100kPa, cells were enlarged with less cellular microvillus and a bigger nucleus; at 200kPa, cells shrank with the sign of apoptosis, and apoptosis cells were found. The mechanical loading of 150kPa is the moderate pressure for chondrocyte: cell proliferation and apoptosis is balanced, necrosis is reduced, and chondrogenesis and chondrocyte hypertrophy are promoted. When the pressure is lower, chondrogenesis and chondrocyte hypertrophy are inhibited. At 200kPa, degeneration of cartilage is implied. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Bex2 regulates cell proliferation and apoptosis in malignant glioma cells via the c-Jun NH2-terminal kinase pathway

    International Nuclear Information System (INIS)

    Zhou, Xiuping; Meng, Qingming; Xu, Xuebin; Zhi, Tongle; Shi, Qiong; Wang, Yong; Yu, Rutong

    2012-01-01

    Highlights: ► The expression levels of Bex2 markedly increased in glioma tissues. ► Bex2 over-expression promoted cell proliferation, while its down-regulation inhibited cell growth. ► Bex2 down-regulation promoted cell apoptosis via JNK/c-Jun signaling pathway. -- Abstract: The function of Bex2, a member of the Brain Expressed X-linked gene family, in glioma is controversial and its mechanism is largely unknown. We report here that Bex2 regulates cell proliferation and apoptosis in malignant glioma cells via the c-Jun NH2-terminal kinase (JNK) pathway. The expression level of Bex2 is markedly increased in glioma tissues. We observed that Bex2 over-expression promotes cell proliferation, while down-regulation of Bex2 inhibits cell growth. Furthermore, Bex2 down-regulation promotes cell apoptosis and activates the JNK pathway; these effects were abolished by administration of the JNK specific inhibitor, (SP600125). Thus, Bex2 may be an important player during the development of glioma.

  7. Stromal-epithelial interactions in aging and cancer: Senescent fibroblasts alter epithelial cell differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Parrinello, Simona; Coppe, Jean-Philippe; Krtolica, Ana; Campisi, Judith

    2004-07-14

    Cellular senescence suppresses cancer by arresting cells at risk for malignant tumorigenesis. However, senescent cells also secrete molecules that can stimulate premalignant cells to proliferate and form tumors, suggesting the senescence response is antagonistically pleiotropic. We show that premalignant mammary epithelial cells exposed to senescent human fibroblasts in mice irreversibly lose differentiated properties, become invasive and undergo full malignant transformation. Moreover, using cultured mouse or human fibroblasts and non-malignant breast epithelial cells, we show that senescent fibroblasts disrupt epithelial alveolar morphogenesis, functional differentiation, and branching morphogenesis. Further, we identify MMP-3 as the major factor responsible for the effects of senescent fibroblasts on branching morphogenesis. Our findings support the idea that senescent cells contribute to age-related pathology, including cancer, and describe a new property of senescent fibroblasts--the ability to alter epithelial differentiation--that might also explain the loss of tissue function and organization that is a hallmark of aging.

  8. Ring-like distribution of constitutive heterochromatin in bovine senescent cells.

    Science.gov (United States)

    Pichugin, Andrey; Beaujean, Nathalie; Vignon, Xavier; Vassetzky, Yegor

    2011-01-01

    Cells that reach "Hayflick limit" of proliferation, known as senescent cells, possess a particular type of nuclear architecture. Human senescent cells are characterized by the presence of highly condensed senescent associated heterochromatin foci (SAHF) that can be detected both by immunostaining for histone H3 three-methylated at lysine 9 (H3K9me3) and by DAPI counterstaining. We have studied nuclear architecture in bovine senescent cells using a combination of immunofluorescence and 3D fluorescent in-situ hybridization (FISH). Analysis of heterochromatin distribution in bovine senescent cells using fluorescent in situ hybridization for pericentric chromosomal regions, immunostaining of H3K9me3, centromeric proteins CENP A/B and DNA methylation showed a lower level of heterochromatin condensation as compared to young cells. No SAHF foci were observed. Instead, we observed fibrous ring-like or ribbon-like heterochromatin patterns that were undetectable with DAPI counterstaining. These heterochromatin fibers were associated with nucleoli. Constitutive heterochromatin in bovine senescent cells is organized in ring-like structures.

  9. Ring-like distribution of constitutive heterochromatin in bovine senescent cells.

    Directory of Open Access Journals (Sweden)

    Andrey Pichugin

    Full Text Available BACKGROUND: Cells that reach "Hayflick limit" of proliferation, known as senescent cells, possess a particular type of nuclear architecture. Human senescent cells are characterized by the presence of highly condensed senescent associated heterochromatin foci (SAHF that can be detected both by immunostaining for histone H3 three-methylated at lysine 9 (H3K9me3 and by DAPI counterstaining. METHODS: We have studied nuclear architecture in bovine senescent cells using a combination of immunofluorescence and 3D fluorescent in-situ hybridization (FISH. RESULTS: Analysis of heterochromatin distribution in bovine senescent cells using fluorescent in situ hybridization for pericentric chromosomal regions, immunostaining of H3K9me3, centromeric proteins CENP A/B and DNA methylation showed a lower level of heterochromatin condensation as compared to young cells. No SAHF foci were observed. Instead, we observed fibrous ring-like or ribbon-like heterochromatin patterns that were undetectable with DAPI counterstaining. These heterochromatin fibers were associated with nucleoli. CONCLUSIONS: Constitutive heterochromatin in bovine senescent cells is organized in ring-like structures.

  10. Exploring cell apoptosis and senescence to understand and treat cancer: an interview with Scott Lowe.

    Science.gov (United States)

    Lowe, Scott; Cifra, Alessandra

    2015-11-01

    Scott W. Lowe is currently principal investigator at the Memorial Sloan-Kettering Cancer Center. After beginning his studies in chemical engineering, he decided to take another path and became fascinated by biochemistry, genetics and molecular biology, which ultimately led to an interest in human disease, particularly cancer. During his PhD at the Massachusetts Institute of Technology (MIT), Scott had the opportunity to benefit from the exceptional mentorship of Earl Ruley, David Housman and Tyler Jacks, and contributed to elucidating how the p53 (TP53) tumor suppressor gene limits oncogenic transformation and modulates the cytotoxic response to conventional chemotherapy. This important work earned him a fellowship from the Cold Spring Harbor Laboratory, which helped to launch his independent career. Scott is now a leading scientist in the cancer field and his work has helped to shed light on mechanisms of cell apoptosis and senescence to better understand and treat cancer. In this interview, he talks about this incredible scientific journey. © 2015. Published by The Company of Biologists Ltd.

  11. Linc00472 suppresses proliferation and promotes apoptosis through elevating PDCD4 expression by sponging miR-196a in colorectal cancer.

    Science.gov (United States)

    Ye, Yafei; Yang, Shengnan; Han, Yanping; Sun, Jingjing; Xv, Lijuan; Wu, Lina; Wang, Yongfeng; Ming, Liang

    2018-06-21

    Long intergenic non-coding RNA Linc00472 has been considered as a tumor suppressor in some cancers. However, the function and mechanism of Linc00472 in colorectal cancer has not been well elucidated. In this study, we found that Linc00472 was down-regulated in colorectal cancer tissues and cells. Elevated Linc00472 expression suppressed proliferation and induced apoptosis in colorectal cancer cells. Moreover, Linc00472 acted as a competing endogenous RNA (ceRNA) of miR-196a to release programmed cell death 4 (PDCD4). Furthermore, miR-196a overexpression or PDCD4 knockdown reversed Linc00472-mediated proliferation inhibition and apoptosis induction in colorectal cancer cells. Ectopic Linc00472 expression hindered tumor growth in vivo . Our study demonstrated that Linc00472 suppressed proliferation and induced apoptosis through up-regulating PDCD4 by decoying miR-196a, which may be an effective therapeutic target for colorectal cancer.

  12. biomedical challenges of human senescence: a review

    African Journals Online (AJOL)

    2002-12-12

    Dec 12, 2002 ... generation per mitochondrion. Understanding the role of cellular ageing in vivo is another major challenge for integrative study. The in vitro model of cell replicative senescence pioneered by. Sith and Pereira has elucidated the mechanisms limiting cell proliferation(30). Until recently the link between in.

  13. JNK inhibition sensitizes tumor cells to radiation-induced premature senescence via Bcl-2/ROS/DDR signaling pathway

    International Nuclear Information System (INIS)

    Lee, Jae Seon; Lee, Je Jung

    2009-01-01

    Premature senescence is considered as a cellular defense mechanism to prevent tumorigenesis. Although recent evidences demonstrate that c-Jun N-terminal kinase (JNK) is involved in the senescence process, the target and exact mechanism of JNK signaling in the regulation of cell proliferation has yet to be defined. In this study, we investigated the role of JNK in premature senescence and demonstrated JNK inhibition sensitized tumor cells to radiation-induced premature senescence

  14. Identification of Secreted Proteins from Ionizing Radiation-Induced Senescent MCF7 Cells Using Comparative Proteomics

    International Nuclear Information System (INIS)

    Han, Na Kyung; Kim, Han Na; Hong, Mi Na; Park, Su Min; Lee, Jae Seon; Chi, Seong Gil

    2010-01-01

    Cellular senescence was first described by Hayflick and Moorhead in 1961 who observed that cultures of normal human fibroblasts had a limited replicative potential and eventually became irreversibly arrest. The majority of senescent cells assume a characteristic flattened and enlarged morphological change, senescence associated β-galactosidase positivity and over the years a large number of molecular phenotypes have been described, such as changes in gene expression, protein processing and chromatin organization. In contrast to apoptosis, senescence does not destroy the cells but leaves them metabolically and synthetically active and therefore able to affect their microenvironment. In particular, senescent fibroblasts and some cancer cells were found to secrete proteins with known or putative tumor-promoting functions such as growth factors or proteolytic enzymes. However, the knowledge about secreted proteins from senescent tumor cells and their functions to surrounding cells is still lacking. In this study, changes of senescence-associated secretory protein expression profile were observed in MCF7 human breast cancer cells exposed to gamma-ray radiation using two dimensional electrophoresis. Also, we identified up-regulated secretory proteins during ionizing radiation-induced cellular senescence

  15. Identification of Secreted Proteins from Ionizing Radiation-Induced Senescent MCF7 Cells Using Comparative Proteomics

    Energy Technology Data Exchange (ETDEWEB)

    Han, Na Kyung; Kim, Han Na; Hong, Mi Na; Park, Su Min; Lee, Jae Seon [Korea Institue of Radiological and Medical Sciences, Seoul (Korea, Republic of); Chi, Seong Gil [Korea University, Seoul (Korea, Republic of)

    2010-05-15

    Cellular senescence was first described by Hayflick and Moorhead in 1961 who observed that cultures of normal human fibroblasts had a limited replicative potential and eventually became irreversibly arrest. The majority of senescent cells assume a characteristic flattened and enlarged morphological change, senescence associated beta-galactosidase positivity and over the years a large number of molecular phenotypes have been described, such as changes in gene expression, protein processing and chromatin organization. In contrast to apoptosis, senescence does not destroy the cells but leaves them metabolically and synthetically active and therefore able to affect their microenvironment. In particular, senescent fibroblasts and some cancer cells were found to secrete proteins with known or putative tumor-promoting functions such as growth factors or proteolytic enzymes. However, the knowledge about secreted proteins from senescent tumor cells and their functions to surrounding cells is still lacking. In this study, changes of senescence-associated secretory protein expression profile were observed in MCF7 human breast cancer cells exposed to gamma-ray radiation using two dimensional electrophoresis. Also, we identified up-regulated secretory proteins during ionizing radiation-induced cellular senescence

  16. In Vivo and In Vitro Effects of ATM/ATR Signaling Pathway on Proliferation, Apoptosis, and Radiosensitivity of Nasopharyngeal Carcinoma Cells.

    Science.gov (United States)

    Wang, Ming; Liu, Gang; Shan, Guo-Ping; Wang, Bing-Bing

    2017-08-01

    The study investigated the ability of ataxia-telangiectasia mutated (ATM)/Rad3-related (ATR) signaling pathway to influence the proliferation, apoptosis, and radiosensitivity of nasopharyngeal carcinoma (NPC) cells. NPC tissues and corresponding adjacent normal tissues were collected from 143 NPC patients. The NPC CNE2 cells were assigned into a control group, X-ray group, CGK-733 group, and X-ray+CGK-733 group. The mRNA levels of ATM and ATR were evaluated using quantitative real-time polymerase chain reaction (qRT-PCR) and the protein levels of ATM and ATR using western blotting. The positive expression of ATM and ATR in tissues and nude mouse tumor tissues was determined by immunohistochemistry. Cell proliferation, migration, invasion, and apoptosis rates were analyzed by the 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di- phenytetrazoliumromide (MTT) assay, scratch test, transwell assay, and flow cytometry, respectively. A nude mouse model of NPC was established to observe tumor volume and growth. The mRNA levels of ATR and ATM and the expression of ATR and ATM protein in NPC tissues were significantly higher than those in adjacent normal tissues. The colony formation assay showed that the colony-forming rate decreased, showing radiation dose-dependent and CGK-733 concentration-dependent manners. Expression of ATM, ATR, Chk1, and Chk2 was evidently increased in the X-ray, CGK-733, and X-ray+CGK-733groups compared with the control group, and the aforementioned expression was highest in the X-ray+CGK-733 group among the four groups. The cell proliferation, invasion, and migration were decreased, tumor volume decreased and cell apoptosis increased in the X-ray, CGK-733, and X-ray+CGK-733 groups compared with the control group; the X-ray+CGK-733 group exhibited lowest cell proliferation, invasion and migration, smallest tumor volume, and highest cell apoptosis among the four groups. Inhibition of ATM/ATR signaling pathway reduces proliferation and enhances apoptosis and

  17. Protein oxidation and degradation during proliferative senescence of human MRC-5 fibroblasts.

    Science.gov (United States)

    Sitte, N; Merker, K; von Zglinicki, T; Grune, T

    2000-03-01

    One of the highlights of age-related changes of cellular metabolism is the accumulation of oxidized proteins. The aging process on a cellular level can be treated either as the ongoing proliferation until a certain number of cell divisions is reached (the Hayflick limit) or as the aging of nondividing cells, that is, the age-related changes in cells without proliferation. The present investigation was undertaken to reveal the changes in protein turnover, proteasome activity, and protein oxidation status during proliferative senescence. We were able to demonstrate that the activity of the cytosolic proteasomal system declines dramatically during the proliferative senescence of human MRC-5 fibroblasts. Regardless of the loss in activity, it could be demonstrated that there are no changes in the transcription and translation of proteasomal subunits. This decline in proteasome activity was accompanied by an increased concentration of oxidized proteins. Cells at higher proliferation stages were no longer able to respond with increased degradation of endogenous [(35)S]-Met-radiolabeled proteins after hydrogen peroxide- or quinone-induced oxidative stress. It could be demonstrated that oxidized proteins in senescent human MRC-5 fibroblasts are not as quickly removed as they are in young cells. Therefore, our study demonstrates that the accumulation of oxidized proteins and decline in protein turnover and activity of the proteasomal system are not only a process of postmitotic aging but also occur during proliferative senescence and result in an increased half-life of oxidized proteins.

  18. Comprehensive suppression of all apoptosis-induced proliferation pathways as a proposed approach to colorectal cancer prevention and therapy.

    Directory of Open Access Journals (Sweden)

    Michael Bordonaro

    Full Text Available Mutations in the WNT/beta-catenin pathway are present in the majority of all sporadic colorectal cancers (CRCs, and histone deacetylase inhibitors induce apoptosis in CRC cells with such mutations. This apoptosis is counteracted by (1 the signaling heterogeneity of CRC cell populations, and (2 the survival pathways induced by mitogens secreted from apoptotic cells. The phenomena of signaling heterogeneity and apoptosis-induced survival constitute the immediate mechanisms of resistance to histone deacetylase inhibitors, and probably other chemotherapeutic agents. We explored the strategy of augmenting CRC cell death by inhibiting all survival pathways induced by the pro-apoptotic agent LBH589, a histone deacetylase inhibitor: AKT, JAK/STAT, and ERK signaling. The apoptosis-enhancing ability of a cocktail of synthetic inhibitors of proliferation was compared to the effects of the natural product propolis. We utilized colorectal adenoma, drug-sensitive and drug-resistant colorectal carcinoma cells to evaluate the apoptotic potential of the combination treatments. The results suggest that an effective approach to CRC combination therapy is to combine apoptosis-inducing drugs (e.g., histone deacetylase inhibitors, such as LBH589 with agents that suppress all compensatory survival pathways induced during apoptosis (such as the cocktail of inhibitors of apoptosis-associated proliferation. The same paradigm can be applied to a CRC prevention approach, as the apoptotic effect of butyrate, a diet-derived histone deacetylase inhibitor, is augmented by other dietary agents that modulate survival pathways (e.g., propolis and coffee extract. Thus, dietary supplements composed by fermentable fiber, propolis, and coffee extract may effectively counteract neoplastic growth in the colon.

  19. Effects of miRNA-197 overexpression on proliferation, apoptosis and migration in levonorgestrel treated uterine leiomyoma cells.

    Science.gov (United States)

    Wu, Xiaoli; Ling, Jing; Fu, Ziyi; Ji, Chenbo; Wu, Jiangping; Xu, Qing

    2015-04-01

    Uterine leiomyoma is the ahead benign tumor of the female genital tract, which resulted in menstrual abnormalities, recurrent pregnancy loss, and other serious gynecological disorders in women. Recently, as the process of exploring the brief molecular mechanisms of tumorgenesis, microRNAs (miRNAs) have attracted much more attention. In this study, we first confirmed that microRNA-197 (miR-197) was down-regulated significantly in human uterus leiomyoma by quantity real-time polymerase chain reaction, compared to normal uterus myometrium. Then we observed the potential effects of miR-197 overexpression on human uterus leiomyoma cells by cell counting kit 8, wound healing assay, and flow cytometric assessment separately. The data showed that miR-197 could inhibit cell proliferation, induce cell apoptosis, and block cell migration in vitro. Coincidently, levonorgestrel (LNG), a well-known uterus leiomyoma therapy, could induce miR-197 expression in human uterus leiomyoma cells, and over-expression of miR-197 showed a synergy effect on human uterus leiomyoma cell proliferation and apoptosis with LNG. In this study, the data showed that miR-197 could play an anti-oncogenic role in human uterus leiomyoma cells, and cooperate with LNG on the cell proliferation and apoptosis, which suggested that miR-197 might be a potential target and provided database for clinical treatment. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  20. Somatostatin and opioid receptors do not regulate proliferation or apoptosis of the human multiple myeloma U266 cells

    Directory of Open Access Journals (Sweden)

    Allouche Stéphane

    2009-06-01

    Full Text Available Abstract Background opioid and somatostatin receptors (SSTRs that can assemble as heterodimer were individually reported to modulate malignant cell proliferation and to favour apoptosis. Materials and methods: SSTRs and opioid receptors expression were examined by RT-PCR, western-blot and binding assays, cell proliferation was studied by XTT assay and propidium iodide (PI staining and apoptosis by annexin V-PI labelling. Results almost all human malignant haematological cell lines studied here expressed the five SSTRs. Further experiments were conducted on the human U266 multiple myeloma cells, which express also μ-opioid receptors (MOP-R. XTT assays and cell cycle studies provide no evidence for a significant effect upon opioid or somatostatin receptors stimulation. Furthermore, neither direct effect nor potentiation of the Fas-receptor pathway was detected on apoptosis after these treatments. Conclusion these data suggest that SSTRs or opioid receptors expression is not a guaranty for an anti-tumoral action in U266 cell line.

  1. UV light induces premature senescence in Akt1-null mouse embryonic fibroblasts by increasing intracellular levels of ROS

    International Nuclear Information System (INIS)

    Jee, Hye Jin; Kim, Hyun-Ju; Kim, Ae Jeong; Bae, Yoe-Sik; Bae, Sun Sik; Yun, Jeanho

    2009-01-01

    Akt/PKB plays a pivotal role in cell survival and proliferation. Previously, we reported that UV-irradiation induces extensive cell death in Akt2 -/- mouse embryonic fibroblasts (MEFs) while Akt1 -/- MEFs show cell cycle arrest. Here, we find that Akt1 -/- MEFs exhibit phenotypic changes characteristics of senescence upon UV-irradiation. An enlarged and flattened morphology, a reduced cell proliferation and an increased senescence-associated β-galactosidase (SA β-gal) staining indicate that Akt1 -/- MEFs undergo premature senescence after UV-irradiation. Restoring Akt1 expression in Akt1 -/- MEFs suppressed SA β-gal activity, indicating that UV-induced senescence is due to the absence of Akt1 function. Notably, levels of ROS were rapidly increased upon UV-irradiation and the ROS scavenger NAC inhibits UV-induced senescence of Akt1 -/- MEFs, suggesting that UV light induces premature senescence in Akt1 -/- MEFs by modulating intracellular levels of ROS. In conjunction with our previous work, this indicates that different isoforms of Akt have distinct function in response to UV-irradiation.

  2. Stress-induced premature senescence (SIPS)--influence of SIPS on radiotherapy.

    Science.gov (United States)

    Suzuki, Masatoshi; Boothman, David A

    2008-03-01

    Replicative senescence is a fundamental feature in normal human diploid cells and results from dysfunctional telomeres at the Hayflick cell division limit. Ionizing radiation (IR) prematurely induces the same phenotypes as replicative senescence prior to the Hayflick limit. This process is known as stress-induced premature senescence (SIPS). Since the cell cycle is irreversibly arrested in SIPS-induced cells, even if they are stimulated by various growth factors, it is thought that SIPS is a form of cell death, irreversibly eliminating replicating cells. IR-induced-focus formation of DNA repair proteins, a marker of DNA damage, is detected in SIPS as well as replicative senescent cells. Furthermore, both processes persistently induce cell cycle checkpoint mechanisms, indicating DNA damage created by ionizing radiation induces SIPS in normal cells, possibly by the same mechanisms as those occurring in replicative senescence. Interestingly, IR induces SIPS not only in normal cells, but also in tumor cells. Due to the expression of telomerase in tumor cells, telomere-dependent replicative senescence does not occur. However, SIPS is induced under certain conditions after IR exposure. Thus, cell death triggered by IR can be attributed to apoptosis or SIPS in tumor cells. However, metabolic function remains intact in SIPS-induced cancer cells, and recent studies show that senescence eliminate cells undergoing SIPS secrete various kinds of factors outside the cell, changing the microenvironment. Evidence using co-culture systems containing normal senescent stromal cells and epithelial tumor cells show that factors secreted from senescent stroma cells promote the growth of tumor epithelial cells both in vitro and in vivo. Thus, regulation of factors secreted from SIPS-induced stromal cells, as well as tumor cells, may affect radiotherapy.

  3. Stress-induced premature senescence (SIPS). Influence of SIPS on radiotherapy

    International Nuclear Information System (INIS)

    Suzuki, Masatoshi; Boothman, D.A.

    2008-01-01

    Replicative senescence is a fundamental feature in normal human diploid cells and results from dysfunctional telomeres at the Hayflick cell division limit. Ionizing radiation (IR) prematurely induces the same phenotypes as replicative senescence prior to the Hayflick limit. This process is known as stress-induced premature senescence (SIPS). Since the cell cycle is irreversibly arrested in SIPS-induced cells, even if they are stimulated by various growth factors, it is thought that SIPS is a form of cell death, irreversibly eliminating replicating cells. IR-induced-focus formation of DNA repair proteins, a marker of DNA damage, is detected in SIPS as well as replicative senescent cells. Furthermore, both processes persistently induce cell cycle checkpoint mechanisms, indicating DNA damage created by ionizing radiation induces SIPS in normal cells, possibly by the same mechanisms as those occurring in replicative senescence. Interestingly, IR induces SIPS not only in normal cells, but also in tumor cells. Due to the expression of telomerase in tumor cells, telomere-dependent replicative senescence does not occur. However, SIPS is induced under certain conditions after IR exposure. Thus, cell death triggered by IR can be attributed to apoptosis or SIPS in tumor cells. However, metabolic function remains intact in SIPS-induced cancer cells, and recent studies show that senescence eliminate cells undergoing SIPS secrete various kinds of factors outside the cell, changing the microenvironment. Evidence using co-culture systems containing normal senescent stromal cells and epithelial tumor cells show that factors secreted from senescent stroma cells promote the growth of tumor epithelial cells both in vitro and in vivo. Thus, regulation of factors secreted from SIPS-induced stromal cells, as well as tumor cells, may affect radiotherapy. (author)

  4. Kaempferol suppresses bladder cancer tumor growth by inhibiting cell proliferation and inducing apoptosis.

    Science.gov (United States)

    Dang, Qiang; Song, Wenbin; Xu, Defeng; Ma, Yanmin; Li, Feng; Zeng, Jin; Zhu, Guodong; Wang, Xinyang; Chang, Luke S; He, Dalin; Li, Lei

    2015-09-01

    The effects of the flavonoid compound, kaempferol, which is an inhibitor of cancer cell proliferation and an inducer of cell apoptosis have been shown in various cancers, including lung, pancreatic, and ovarian, but its effect has never been studied in bladder cancer. Here, we investigated the effects of kaempferol on bladder cancer using multiple in vitro cell lines and in vivo mice studies. The MTT assay results on various bladder cancer cell lines showed that kaempferol enhanced bladder cancer cell cytotoxicity. In contrast, when analyzed by the flow cytometric analysis, DNA ladder experiment, and TUNEL assay, kaempferol significantly was shown to induce apoptosis and cell cycle arrest. These in vitro results were confirmed in in vivo mice studies using subcutaneous xenografted mouse models. Consistent with the in vitro results, we found that treating mice with kaempferol significant suppression in tumor growth compared to the control group mice. Tumor tissue staining results showed decreased expressions of the growth related markers, yet increased expressions in apoptosis markers in the kaempferol treated group mice tissues compared to the control group mice. In addition, our in vitro and in vivo data showed kaempferol can also inhibit bladder cancer invasion and metastasis. Further mechanism dissection studies showed that significant down-regulation of the c-Met/p38 signaling pathway is responsible for the kaempferol mediated cell proliferation inhibition. All these findings suggest kaempferol might be an effective and novel chemotherapeutic drug to apply for the future therapeutic agent to combat bladder cancer. © 2014 Wiley Periodicals, Inc.

  5. Effects of radiofrequency exposure emitted from a GSM mobile phone on proliferation, differentiation, and apoptosis of neural stem cells

    Science.gov (United States)

    Eghlidospour, Mahsa; Ghanbari, Amir

    2017-01-01

    Due to the importance of neural stem cells (NSCs) in plasticity of the nervous system and treating neurodegenerative diseases, the main goal of this study was to evaluate the effects of radiofrequency radiation emitted from a GSM 900-MHz mobile phone with different exposure duration on proliferation, differentiation and apoptosis of adult murine NSCs in vitro. We used neurosphere assay to evaluate NSCs proliferation, and immunofluorescence assay of neural cell markers to examine NSCs differentiation. We also employed alamarBlue and caspase 3 apoptosis assays to assess harmful effects of mobile phone on NSCs. Our results showed that the number and size of resulting neurospheres and also the percentage of cells differentiated into neurons decreased significantly with increasing exposure duration to GSM 900-MHz radiofrequency (RF)-electromagnetic field (EMF). In contrast, exposure to GSM 900-MHz RF-EMF at different durations did not influence cell viability and apoptosis of NSCs and also their astrocytic differentiation. It is concluded that accumulating dose of GSM 900-MHz RF-EMF might have devastating effects on NSCs proliferation and neurogenesis requiring more causations in terms of using mobile devices. PMID:28713615

  6. Downregulation of mouse CCR3 by lentiviral shRNA inhibits proliferation and induces apoptosis of mouse eosinophils.

    Science.gov (United States)

    Zhu, Xin-Hua; Liao, Bing; Xu, Yi; Liu, Ke; Huang, Yun; Huang, Quan-Long; Liu, Yue-Hui

    2017-02-01

    RNA interference has been considered as an effective gene silencing method in basic and preclinical investigations. The aims of the present study were to construct a lentiviral vector expressing a short hairpin RNA (shRNA) targeting the murine CC chemokine receptor 3 (mCCR3), and to investigate its effects on the proliferation and apoptosis of mouse eosinophils. A recombinant lentiviral vector expressing four fragments of mouse CCR3 shRNA (pLVX‑mCCR3‑1+2+3+4‑shRNA) was constructed using subcloning techniques. This novel lentivirus was then packaged into 293T cells by co‑transduction with plasmids, including Baculo p35, pCMV R8.2 and VSV. The interference effects of the vector were verified using polymerase chain reaction (PCR) and western blot analyses. The effects of the interference on the proliferation and apoptosis of mouse eosinophils were investigated using 3‑(4,5‑dimethylthiazol‑2‑yl)‑5‑(3‑carboxymethoxyphenyl)‑2‑(4‑sulfophenyl)‑2H‑tetrazolium and terminal deoxynucleotidyl transferase dUTP nick end labeling methods, respectively. The results of the PCR and western blot analyses confirmed that the novel recombinant vector, pLVX‑mCCR3‑1+2+3+4‑shRNA, had high efficiency in inhibiting the mRNA and protein expression levels of mCCR3 in mouse eosinophils. The downregulation of mCCR3 significantly inhibited proliferation of the eosinophils. Furthermore, the present study found that the downregulation of mCCR3 significantly promoted apoptosis of the eosinophils. Therefore, the downregulation of mCCR3 led to the inhibition of proliferation and induction of apoptosis in mouse eosinophils. The predominant characteristics of allergic rhinitis are eosinophil infiltration and release of inflammatory mediators, which appear in a variety of clinical manifestations. The results of the present study indicate that mCCR3 silencing may serve as a putative approach for the treatment of allergic rhinitis.

  7. Swelling-activated ion channels: functional regulation in cell-swelling, proliferation and apoptosis

    DEFF Research Database (Denmark)

    Stutzin, A; Hoffmann, E K

    2006-01-01

    Cell volume regulation is one of the most fundamental homeostatic mechanisms and essential for normal cellular function. At the same time, however, many physiological mechanisms are associated with regulatory changes in cell size meaning that the set point for cell volume regulation is under phys...... as key players in the maintenance of normal steady-state cell volume, with particular emphasis on the intracellular signalling pathways responsible for their regulation during hypotonic stress, cell proliferation and apoptosis....

  8. Integrin Beta 3 Regulates Cellular Senescence by Activating the TGF-β Pathway

    Directory of Open Access Journals (Sweden)

    Valentina Rapisarda

    2017-03-01

    Full Text Available Cellular senescence is an important in vivo mechanism that prevents the propagation of damaged cells. However, the precise mechanisms regulating senescence are not well characterized. Here, we find that ITGB3 (integrin beta 3 or β3 is regulated by the Polycomb protein CBX7. β3 expression accelerates the onset of senescence in human primary fibroblasts by activating the transforming growth factor β (TGF-β pathway in a cell-autonomous and non-cell-autonomous manner. β3 levels are dynamically increased during oncogene-induced senescence (OIS through CBX7 Polycomb regulation, and downregulation of β3 levels overrides OIS and therapy-induced senescence (TIS, independently of its ligand-binding activity. Moreover, cilengitide, an αvβ3 antagonist, has the ability to block the senescence-associated secretory phenotype (SASP without affecting proliferation. Finally, we show an increase in β3 levels in a subset of tissues during aging. Altogether, our data show that integrin β3 subunit is a marker and regulator of senescence.

  9. Resveratrol Induced Premature Senescence Is Associated with DNA Damage Mediated SIRT1 and SIRT2 Down-Regulation.

    Directory of Open Access Journals (Sweden)

    Mehtap Kilic Eren

    Full Text Available The natural polyphenolic compound resveratrol (3,4,5-trihydroxy-trans-stilbene has broad spectrum health beneficial activities including antioxidant, anti-inflammatory, anti-aging, anti-cancer, cardioprotective, and neuroprotective effects. Remarkably, resveratrol also induces apoptosis and cellular senescence in primary and cancer cells. Resveratrol's anti-aging effects both in vitro and in vivo attributed to activation of a (NAD-dependent histone deacetylase family member sirtuin-1 (SIRT1 protein. In mammals seven members (SIRT1-7 of sirtuin family have been identified. Among those, SIRT1 is the most extensively studied with perceptive effects on mammalian physiology and suppression of the diseases of aging. Yet no data has specified the role of sirtuins, under conditions where resveratrol treatment induces senescence. Current study was undertaken to investigate the effects of resveratrol in human primary dermal fibroblasts (BJ and to clarify the role of sirtuin family members in particular SIRT1 and SIRT2 that are known to be involved in cellular stress responses and cell cycle, respectively. Here, we show that resveratrol decreases proliferation of BJ cells in a time and dose dependent manner. In addition the increase in senescence associated β-galactosidase (SA-β-gal activity and methylated H3K9-me indicate the induction of premature senescence. A significant increase in phosphorylation of γ-H2AX, a surrogate of DNA double strand breaks, as well as in levels of p53, p21CIP1 and p16INK4A is also detected. Interestingly, at concentrations where resveratrol induced premature senescence we show a significant decrease in SIRT1 and SIRT2 levels by Western Blot and quantitative RT-PCR analysis. Conversely inhibition of SIRT1 and SIRT2 via siRNA or sirtinol treatment also induced senescence in BJ fibroblasts associated with increased SA-β-gal activity, γ-H2AX phosphorylation and p53, p21CIP1 and p16INK4A levels. Interestingly DNA damaging

  10. [Effects of 17-AAG on the proliferation and apoptosis of human lung cancer A549 and H446 cells].

    Science.gov (United States)

    Niu, Ben; Lin, Jingshuang; Feng, Tao

    2015-04-01

    To observe the effect of 17-(allylamino)-17-demethoxygeldanamycin (17-AAG) on the apoptosis of human lung cancer cell lines A549 and H446, and to investigate the potential mechanisms. Proliferation inhibition and apoptosis assays, and the cell cycles were detected by MTT and flow cytometry respectively. Western blot was used to determine the expression level of proteins such as Hsp90, Hsp70, AKt, Her-2, Bcl-2 and Bax. After treated with 17-AAG, the proliferation of both A549 and H446 cells was inhibited significantly in a dose-dependent manner; as the concentration of 17-AAG was from 50 to 500 nmol/L, the IC₅₀ values to A549 and H446 cell lines were (222 ± 13) nmol/L and (189 ± 7) nmol/L respectively at 48 h. Cell cycle assays showed that 17-AAG was able to arrest cell cycles of A549 and H446 cell lines at the G₂/M phase. Apoptosis assay showed that 17-AAG was capable of inducing apoptosis in A549 and H446 cell lines. After treated with 17-AAG for 48 h, there were significant differences between the 400 nmol/L groups(46.3% for A549 cell line and 56.9% for H446 cell line) and the control group (11.9% for A549 cell line and 6.9% for H446 cell line, P AAG treatment: Akt and Her-2 decreased significantly while the expression of Hsp70 increased. Meanwhile, the expression of Bcl-2 decreased but that of Bax increased, indicating that 17-AAG was able to promote apoptosis mode in A549 and H446 cells. 17-AAG can regulate the expression level of apoptosis-related proteins such as Bax and Bcl-2 by Hsp90 signaling pathway in A549 and H446 cells, and ultimately inhibit cell proliferation and induce apoptosis.

  11. In vivo regulation of colonic cell proliferation, differentiation, apoptosis, and P27Kip1 by dietary fish oil and butyrate in rats.

    Science.gov (United States)

    Hong, Mee Young; Turner, Nancy D; Murphy, Mary E; Carroll, Raymond J; Chapkin, Robert S; Lupton, Joanne R

    2015-11-01

    We have shown that dietary fish oil is protective against experimentally induced colon cancer, and the protective effect is enhanced by coadministration of pectin. However, the underlying mechanisms have not been fully elucidated. We hypothesized that fish oil with butyrate, a pectin fermentation product, protects against colon cancer initiation by decreasing cell proliferation and increasing differentiation and apoptosis through a p27(Kip1)-mediated mechanism. Rats were provided diets of corn or fish oil, with/without butyrate, and terminated 12, 24, or 48 hours after azoxymethane (AOM) injection. Proliferation (Ki-67), differentiation (Dolichos Biflorus Agglutinin), apoptosis (TUNEL), and p27(Kip1) (cell-cycle mediator) were measured in the same cell within crypts in order to examine the coordination of cell cycle as a function of diet. DNA damage (N(7)-methylguanine) was determined by quantitative IHC analysis. Dietary fish oil decreased DNA damage by 19% (P = 0.001) and proliferation by 50% (P = 0.003) and increased differentiation by 56% (P = 0.039) compared with corn oil. When combined with butyrate, fish oil enhanced apoptosis 24 hours after AOM injection compared with a corn oil/butyrate diet (P = 0.039). There was an inverse relationship between crypt height and apoptosis in the fish oil/butyrate group (r = -0.53, P = 0.040). The corn oil/butyrate group showed a positive correlation between p27(Kip1) expression and proliferation (r = 0.61, P = 0.035). These results indicate the in vivo effect of butyrate on apoptosis and proliferation is dependent on dietary lipid source. These results demonstrate the presence of an early coordinated colonocyte response by which fish oil and butyrate protects against colon tumorigenesis. ©2015 American Association for Cancer Research.

  12. Effect of L1-ORF2 on senescence of GES-1 cells and its molecular mechanisms

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    Ying-nan LI

    2016-06-01

    Full Text Available Objective  To investigate the effect of long interspersed nuclear elements 1 open reading frame 2(L1-ORF2 gene on the senescence of GES-1 cells and its mechanism of molecular regulation. Methods  Cell culture of high glucose was used to construct stable model of senescent GES-1 cells. L1-ORF2 siRNA vector was constructed and then transfected into normal GES1 and senescent ones with liposome transfection reagents for transient expression. Forty eight hours after transfection, cell growth curves were drawn to show the speed of cell proliferation, flow cytometry was used to analyze the cell cycle, β-galactosidase staining to detect cell aging and Western blotting to detect the expressions of L1-ORF2, P53 and P21proteins. Results  Senescent GES-1 cell model and L1-ORF2 siRNA vector were constructed. Compared with negative control group, the L1-ORF2 expression decreased in normal and senescent GES-1 cells transfected with L1-ORF2 siRNA vector. There was a faster proliferation of senescent GES1 cells (P<0.05 and lower ratio of β-galactosidase (56% vs 69%, P<0.05 and G0/G1 phase (34.2% vs 39.3%, P<0.05 in senescent GES-1 cells transfected with L1-ORE2 siRNA vector than those transfected with negative control vector, while there was no obvious difference between normal GES-1 cells transfected with L1-ORF2 siRNA vector and negative control vector (P>0.05. P53 protein was expressed only in senescent GES-1 cell, while P21 protein was expressed in both normal and senescent GES-1 cells, and the latter had a higher expression level (P<0.05. The GES-1 cells transfected with L1-ORF2 siRNA vector showed lower expressions of P53 and P21 proteins than those transfected with negative control vector (P<0.05. Conclusions  L1-ORF2-siRNA vector could down-regulate the expression of L1-ORF2 protein in normal and senescent GES-1 cells and promote the proliferation of senescent GES-1 cells. P21 and P53 proteins participate in the process of L1-ORF2 regulating

  13. Genome-wide transcriptional reorganization associated with senescence-to-immortality switch during human hepatocellular carcinogenesis.

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    Gokhan Yildiz

    Full Text Available Senescence is a permanent proliferation arrest in response to cell stress such as DNA damage. It contributes strongly to tissue aging and serves as a major barrier against tumor development. Most tumor cells are believed to bypass the senescence barrier (become "immortal" by inactivating growth control genes such as TP53 and CDKN2A. They also reactivate telomerase reverse transcriptase. Senescence-to-immortality transition is accompanied by major phenotypic and biochemical changes mediated by genome-wide transcriptional modifications. This appears to happen during hepatocellular carcinoma (HCC development in patients with liver cirrhosis, however, the accompanying transcriptional changes are virtually unknown. We investigated genome-wide transcriptional changes related to the senescence-to-immortality switch during hepatocellular carcinogenesis. Initially, we performed transcriptome analysis of senescent and immortal clones of Huh7 HCC cell line, and identified genes with significant differential expression to establish a senescence-related gene list. Through the analysis of senescence-related gene expression in different liver tissues we showed that cirrhosis and HCC display expression patterns compatible with senescent and immortal phenotypes, respectively; dysplasia being a transitional state. Gene set enrichment analysis revealed that cirrhosis/senescence-associated genes were preferentially expressed in non-tumor tissues, less malignant tumors, and differentiated or senescent cells. In contrast, HCC/immortality genes were up-regulated in tumor tissues, or more malignant tumors and progenitor cells. In HCC tumors and immortal cells genes involved in DNA repair, cell cycle, telomere extension and branched chain amino acid metabolism were up-regulated, whereas genes involved in cell signaling, as well as in drug, lipid, retinoid and glycolytic metabolism were down-regulated. Based on these distinctive gene expression features we developed a 15

  14. Co-targeting Deoxyribonucleic Acid–Dependent Protein Kinase and Poly(Adenosine Diphosphate-Ribose) Polymerase-1 Promotes Accelerated Senescence of Irradiated Cancer Cells

    International Nuclear Information System (INIS)

    Azad, Arun; Bukczynska, Patricia; Jackson, Susan; Haput, Ygal; Cullinane, Carleen; McArthur, Grant A.; Solomon, Benjamin

    2014-01-01

    Purpose: To examine the effects of combined blockade of DNA-dependent protein kinase (DNA-PK) and poly(adenosine diphosphate-ribose) polymerase-1 (PARP-1) on accelerated senescence in irradiated H460 and A549 non-small cell lung cancer cells. Methods and Materials: The effects of KU5788 and AG014699 (inhibitors of DNA-PK and PARP-1, respectively) on clonogenic survival, DNA double-strand breaks (DSBs), apoptosis, mitotic catastrophe, and accelerated senescence in irradiated cells were examined in vitro. For in vivo experiments, H460 xenografts established in athymic nude mice were treated with BEZ235 (a DNA-PK, ATM, and phosphatidylinositol 3-kinase/mammalian target of rapamycin inhibitor) and AG014699 to determine effects on proliferation, DNA DSBs, and accelerated senescence after radiation. Results: Compared with either inhibitor alone, combination treatment with KU57788 and AG014699 reduced postradiation clonogenic survival and significantly increased persistence of Gamma-H2AX (γH2AX) foci in irradiated H460 and A549 cells. Notably, these effects coincided with the induction of accelerated senescence in irradiated cells as reflected by positive β-galactosidase staining, G2-M cell-cycle arrest, enlarged and flattened cellular morphology, increased p21 expression, and senescence-associated cytokine secretion. In irradiated H460 xenografts, concurrent therapy with BEZ235 and AG014699 resulted in sustained Gamma-H2AX (γH2AX) staining and prominent β-galactosidase activity. Conclusion: Combined DNA-PK and PARP-1 blockade increased tumor cell radiosensitivity and enhanced the prosenescent properties of ionizing radiation in vitro and in vivo. These data provide a rationale for further preclinical and clinical testing of this therapeutic combination

  15. Co-targeting Deoxyribonucleic Acid–Dependent Protein Kinase and Poly(Adenosine Diphosphate-Ribose) Polymerase-1 Promotes Accelerated Senescence of Irradiated Cancer Cells

    Energy Technology Data Exchange (ETDEWEB)

    Azad, Arun, E-mail: arun.azad@bccancer.bc.ca [Division of Cancer Research, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Department of Pathology, St. Vincent' s Hospital, University of Melbourne, Parkville, Victoria (Australia); Bukczynska, Patricia; Jackson, Susan [Division of Cancer Research, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Haput, Ygal; Cullinane, Carleen [Division of Cancer Research, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria (Australia); McArthur, Grant A.; Solomon, Benjamin [Division of Cancer Research, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Division of Cancer Medicine, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Department of Medicine, St. Vincent' s Hospital, University of Melbourne, Parkville, Victoria (Australia); Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria (Australia)

    2014-02-01

    Purpose: To examine the effects of combined blockade of DNA-dependent protein kinase (DNA-PK) and poly(adenosine diphosphate-ribose) polymerase-1 (PARP-1) on accelerated senescence in irradiated H460 and A549 non-small cell lung cancer cells. Methods and Materials: The effects of KU5788 and AG014699 (inhibitors of DNA-PK and PARP-1, respectively) on clonogenic survival, DNA double-strand breaks (DSBs), apoptosis, mitotic catastrophe, and accelerated senescence in irradiated cells were examined in vitro. For in vivo experiments, H460 xenografts established in athymic nude mice were treated with BEZ235 (a DNA-PK, ATM, and phosphatidylinositol 3-kinase/mammalian target of rapamycin inhibitor) and AG014699 to determine effects on proliferation, DNA DSBs, and accelerated senescence after radiation. Results: Compared with either inhibitor alone, combination treatment with KU57788 and AG014699 reduced postradiation clonogenic survival and significantly increased persistence of Gamma-H2AX (γH2AX) foci in irradiated H460 and A549 cells. Notably, these effects coincided with the induction of accelerated senescence in irradiated cells as reflected by positive β-galactosidase staining, G2-M cell-cycle arrest, enlarged and flattened cellular morphology, increased p21 expression, and senescence-associated cytokine secretion. In irradiated H460 xenografts, concurrent therapy with BEZ235 and AG014699 resulted in sustained Gamma-H2AX (γH2AX) staining and prominent β-galactosidase activity. Conclusion: Combined DNA-PK and PARP-1 blockade increased tumor cell radiosensitivity and enhanced the prosenescent properties of ionizing radiation in vitro and in vivo. These data provide a rationale for further preclinical and clinical testing of this therapeutic combination.

  16. Zeb1 Is a Potential Regulator of Six2 in the Proliferation, Apoptosis and Migration of Metanephric Mesenchyme Cells

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    Yuping Gu

    2016-08-01

    Full Text Available Nephron progenitor cells surround around the ureteric bud tips (UB and inductively interact with the UB to originate nephrons, the basic units of renal function. This process is determined by the internal balance between self-renewal and consumption of the nephron progenitor cells, which is depending on the complicated regulation networks. It has been reported that Zeb1 regulates the proliferation of mesenchymal cells in mouse embryos. However, the role of Zeb1 in nephrons generation is not clear, especially in metanephric mesenchyme (MM. Here, we detected cell proliferation, apoptosis and migration in MM cells by EdU assay, flow cytometry assay and wound healing assay, respectively. Meanwhile, Western and RT-PCR were used to measure the expression level of Zeb1 and Six2 in MM cells and developing kidney. Besides, the dual-luciferase assay was conducted to study the molecular relationship between Zeb1 and Six2. We found that knock-down of Zeb1 decreased cell proliferation, migration and promoted cell apoptosis in MM cells and Zeb1 overexpression leaded to the opposite data. Western-blot and RT-PCR results showed that knock-down of Zeb1 decreased the expression of Six2 in MM cells and Zeb1 overexpression contributed to the opposite results. Similarly, Zeb1 promoted Six2 promoter reporter activity in luciferase assays. However, double knock-down of Zeb1 and Six2 did not enhance the apoptosis of MM cells compared with control cells. Nevertheless, double silence of Zeb1 and Six2 repressed cell proliferation. In addition, we also found that Zeb1 and Six2 had an identical pattern in distinct developing phases of embryonic kidney. These results indicated that there may exist a complicated regulation network between Six2 and Zeb1. Together, we demonstrate Zeb1 promotes proliferation and apoptosis and inhibits the migration of MM cells, in association with Six2.

  17. Zeb1 Is a Potential Regulator of Six2 in the Proliferation, Apoptosis and Migration of Metanephric Mesenchyme Cells

    Science.gov (United States)

    Gu, Yuping; Zhao, Ya; Zhou, Yuru; Xie, Yajun; Ju, Pan; Long, Yaoshui; Liu, Jianing; Ni, Dongsheng; Cao, Fen; Lyu, Zhongshi; Mao, Zhaomin; Hao, Jin; Li, Yiman; Wan, Qianya; Kanyomse, Quist; Liu, Yamin; Ren, Die; Ning, Yating; Li, Xiaofeng; Zhou, Qin; Li, Bing

    2016-01-01

    Nephron progenitor cells surround around the ureteric bud tips (UB) and inductively interact with the UB to originate nephrons, the basic units of renal function. This process is determined by the internal balance between self-renewal and consumption of the nephron progenitor cells, which is depending on the complicated regulation networks. It has been reported that Zeb1 regulates the proliferation of mesenchymal cells in mouse embryos. However, the role of Zeb1 in nephrons generation is not clear, especially in metanephric mesenchyme (MM). Here, we detected cell proliferation, apoptosis and migration in MM cells by EdU assay, flow cytometry assay and wound healing assay, respectively. Meanwhile, Western and RT-PCR were used to measure the expression level of Zeb1 and Six2 in MM cells and developing kidney. Besides, the dual-luciferase assay was conducted to study the molecular relationship between Zeb1 and Six2. We found that knock-down of Zeb1 decreased cell proliferation, migration and promoted cell apoptosis in MM cells and Zeb1 overexpression leaded to the opposite data. Western-blot and RT-PCR results showed that knock-down of Zeb1 decreased the expression of Six2 in MM cells and Zeb1 overexpression contributed to the opposite results. Similarly, Zeb1 promoted Six2 promoter reporter activity in luciferase assays. However, double knock-down of Zeb1 and Six2 did not enhance the apoptosis of MM cells compared with control cells. Nevertheless, double silence of Zeb1 and Six2 repressed cell proliferation. In addition, we also found that Zeb1 and Six2 had an identical pattern in distinct developing phases of embryonic kidney. These results indicated that there may exist a complicated regulation network between Six2 and Zeb1. Together, we demonstrate Zeb1 promotes proliferation and apoptosis and inhibits the migration of MM cells, in association with Six2. PMID:27509493

  18. Bacterial Intoxication Evokes Cellular Senescence with Persistent DNA Damage and Cytokine Signaling

    DEFF Research Database (Denmark)

    Blazkova, Hana; Krejcikova, Katerina; Moudry, Pavel

    2009-01-01

    to such intoxication are mechanistically incompletely understood. Here we show that both normal and cancer cells (BJ, IMR-90 and WI-38 fibroblasts, HeLa and U2-OS cell lines) that survive the acute phase of intoxication by Haemophilus ducreyi CDT possess the hallmarks of cellular senescence. This characteristic...... mechanistically underlie the 'distended' morphology evoked by CDTs. Finally, the activation of the two anti-cancer barriers, apoptosis and cellular senescence, together with evidence of chromosomal aberrations (micronucleation) reported here, support the emerging genotoxic and potentially oncogenic effects...

  19. Effects of TGF-β1 on the Proliferation and Apoptosis of Human Cervical Cancer Hela Cells In Vitro.

    Science.gov (United States)

    Tao, Ming-Zhu; Gao, Xia; Zhou, Tie-Jun; Guo, Qing-Xi; Zhang, Qiang; Yang, Cheng-Wan

    2015-12-01

    To investigate the effects of TGF-β1 on the proliferation and apoptosis of cervical cancer Hela cells in vitro. Human cervical cancer Hela cells were cultured in vitro and divided into the experimental and control groups. In the experimental groups, Hela cells were stimulated with different concentrations of TGF-β1 (0.01, 0.1, 1, and 10 ng/mL), while Hela cells cultured in serum-free medium without TGF-β1 were used as controls. The CCK8 method was adopted to detect the effect of TGF-β1 on Hela cell proliferation, and flow cytometry was used to determine cell apoptosis 72 h after TGF-β1 treatment. Compared with the control group, the CCK-8 tests showed that different concentrations of TGF-β1 had no obvious effect on Hela cell proliferation 24 h after treatment (P > 0.05). However, upon 48 or 72 h of treatment, TGF-β1 significantly inhibited the proliferation of Hela cells in a time- and dose-dependent manner (P Hela cells in a dose-dependent manner after 72 h of treatment (P Hela cells in vitro.

  20. C/EBPβ Promotes STAT3 Expression and Affects Cell Apoptosis and Proliferation in Porcine Ovarian Granulosa Cells.

    Science.gov (United States)

    Yuan, Xiaolong; Zhou, Xiaofeng; He, Yingting; Zhong, Yuyi; Zhang, Ailing; Zhang, Zhe; Zhang, Hao; Li, Jiaqi

    2018-06-13

    Previous studies suggest that signal transducer and activator of transcription 3 (STAT3) and CCAAT/enhancer binding protein beta (C/EBPβ) play an essential role in ovarian granulosa cells (GCs) for mammalian follicular development. Several C/EBPβ putative binding sites were previously predicted on the STAT3 promoter in mammals. However, the molecular regulation of C/EBPβ on STAT3 and their effects on cell proliferation and apoptosis remain virtually unexplored in GCs. Using porcine GCs as a model, the 5′-deletion, luciferase report assay, mutation, chromatin immunoprecipitation, Annexin-V/PI staining and EdU assays were applied to investigate the molecular mechanism for C/EBPβ regulating the expression of STAT3 and their effects on the cell proliferation and apoptosis ability. We found that over and interfering with the expression of C/EBPβ significantly increased and decreased the messenger RNA (mRNA) and protein levels of STAT3 , respectively. The dual luciferase reporter assay showed that C/EBPβ directly bound at −1397/−1387 of STAT3 to positively regulate the mRNA and protein expressions of STAT3 . Both C/EBPβ and STAT3 were observed to inhibit cell apoptosis and promote cell proliferation. Furthermore, C/EBPβ might enhance the antiapoptotic and pro-proliferative effects of STAT3 . These results would be of great insight in further exploring the molecular mechanism of C/EBPβ and STAT3 on the function of GCs and the development of ovarian follicles in mammals.

  1. Non-Cell Autonomous Effects of the Senescence-Associated Secretory Phenotype in Cancer Therapy

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    Tareq Saleh

    2018-05-01

    Full Text Available In addition to promoting various forms of cell death, most conventional anti-tumor therapies also promote senescence. There is now extensive evidence that therapy-induced senescence (TIS might be transient, raising the concern that TIS could represent an undesirable outcome of therapy by providing a mechanism for tumor dormancy and eventual disease recurrence. The senescence-associated secretory phenotype (SASP is a hallmark of TIS and may contribute to aberrant effects of cancer therapy. Here, we propose that the SASP may also serve as a major driver of escape from senescence and the re-emergence of proliferating tumor cells, wherein factors secreted from the senescent cells contribute to the restoration of tumor growth in a non-cell autonomous fashion. Accordingly, anti-SASP therapies might serve to mitigate the deleterious outcomes of TIS. In addition to providing an overview of the putative actions of the SASP, we discuss recent efforts to identify and eliminate senescent tumor cells.

  2. Balance of life and death in alveolar epithelial type II cells: proliferation, apoptosis, and the effects of cyclic stretch on wound healing.

    Science.gov (United States)

    Crosby, Lynn M; Luellen, Charlean; Zhang, Zhihong; Tague, Larry L; Sinclair, Scott E; Waters, Christopher M

    2011-10-01

    After acute lung injury, repair of the alveolar epithelium occurs on a substrate undergoing cyclic mechanical deformation. While previous studies showed that mechanical stretch increased alveolar epithelial cell necrosis and apoptosis, the impact of cell death during repair was not determined. We examined epithelial repair during cyclic stretch (CS) in a scratch-wound model of primary rat alveolar type II (ATII) cells and found that CS altered the balance between proliferation and cell death. We measured cell migration, size, and density; intercellular gap formation; cell number, proliferation, and apoptosis; cytoskeletal organization; and focal adhesions in response to scratch wounding followed by CS for up to 24 h. Under static conditions, wounds were closed by 24 h, but repair was inhibited by CS. Wounding stimulated cell motility and proliferation, actin and vinculin redistribution, and focal adhesion formation at the wound edge, while CS impeded cell spreading, initiated apoptosis, stimulated cytoskeletal reorganization, and attenuated focal adhesion formation. CS also caused significant intercellular gap formation compared with static cells. Our results suggest that CS alters several mechanisms of epithelial repair and that an imbalance occurs between cell death and proliferation that must be overcome to restore the epithelial barrier.

  3. The role of curcumin on intestinal oxidative stress, cell proliferation and apoptosis after ischemia/reperfusion injury in rats.

    Science.gov (United States)

    Yucel, Ahmet Fikret; Kanter, Mehmet; Pergel, Ahmet; Erboga, Mustafa; Guzel, Ahmet

    2011-12-01

    The aim of this study was to demonstrate the role of curcumin on oxidative stress, cell proliferation and apoptosis in the rat intestinal mucosa after ischemia/reperfusion (I/R). A total of 30 male Wistar albino rats were divided into three groups: sham, I/R and I/R+ curcumin; each group contain 10 animals. Sham group animals underwent laparotomy without I/R injury. After I/R groups animals underwent laparotomy, 1 h of superior mesenteric artery ligation were followed by 1 h of reperfusion. In the curcumin group, 3 days before I/R, curcumin (100 mg/kg) was administered by gastric gavage. All animals were sacrificed at the end of reperfusion and intestinal tissues samples were obtained for biochemical and histopathological investigation in all groups. Curcumin treatment significantly decreased the elevated tissue malondialdehyde levels and increased of reduced superoxide dismutase, and glutathione peroxidase enzyme activities in intestinal tissues samples. I/R caused severe histopathological injury including mucosal erosions and villous congestion and hemorrhage. Curcumin treatment significantly attenuated the severity of intestinal I/R injury, with inhibiting of I/R-induced apoptosis and cell proliferation. These results suggest that curcumin treatment has a protective effect against intestinal damage induced by intestinal I/R. This protective effect is possibly due to its ability to inhibit I/R-induced oxidative stress, apoptosis and cell proliferation.

  4. Progranulin modulates cholangiocarcinoma cell proliferation, apoptosis, and motility via the PI3K/pAkt pathway

    Directory of Open Access Journals (Sweden)

    Daya M

    2018-01-01

    Full Text Available Minerva Daya,1–3 Watcharin Loilome,1,3 Anchalee Techasen,3,4 Malinee Thanee,3 Prakasit Sa-Ngiamwibool,4,5 Attapol Titapun,5,6 Puangrat Yongvanit,3 Nisana Namwat1,31Department of Biochemistry, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand; 2Department of Biochemistry, Faculty of Pharmacy, University of Santo Tomas, Sampaloc, Manila, Philippines; 3Cholangiocarcinoma Research Institute, 4Faculty of Associated Medical Science, 5Department of Pathology, 6Department of Surgery, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand Abstract: Progranulin (PGRN is a growth factor normally expressed in rapidly cycling epithelial cells for growth, differentiation, and motility. Several studies have shown the association of PGRN overexpression with the progression of numerous malignancies, including cholangiocarcinoma (CCA. However, the underlying mechanisms on how PGRN modulates CCA cell proliferation and motility is not clear. In this study, we investigated the prognostic significance of PGRN expression in human CCA tissue and the mechanisms of PGRN modulation of CCA cell proliferation and motility. We found that CCA tissues with high PGRN expression were correlated with poor prognosis and likelihood of metastasis. PGRN knockdown KKU-100 and KKU-213 cells demonstrated a reduced rate of proliferation and colony formation and decreased levels of phosphatidyl inositol-3-kinase (PI3K and phosphorylated Akt (pAkt proteins. Accumulation of cells at the G1 phase was observed and was accompanied by a reduction of cyclin D1 and CDK4 protein levels. Knockdown cells also induced apoptosis by increasing the Bax-to-Bcl-2 ratio. Increased cell apoptosis was confirmed by annexin V-FITC/PI staining. Moreover, suppression of PGRN reduced CCA cell migration and invasion in vitro. Investigating the biomarkers in epithelial–mesenchymal transition (EMT revealed a decrease in the expression of vimentin, snail, and metalloproteinase-9. In

  5. Effects of overexpression of the SH2-containing inositol phosphatase SHIP on proliferation and apoptosis of erythroid AS-E2 cells

    NARCIS (Netherlands)

    Boer, AK; Drayer, AL; Vellenga, E

    Previous studies have demonstrated that SH2-containing inositol phosphatase (SHIP) is involved in the control of B cell, myeloid cell and macrophage activation and proliferation. The goal of the present study was to examine the role of SHIP during proliferation and apoptosis in cells of the

  6. Effects of overexpression of the SH2-containing inositol phosphatase SHIP on proliferation and apoptosis of erythroid AS-E2 cells

    NARCIS (Netherlands)

    Boer, AK; Drayer, AL; Vellenga, E

    2001-01-01

    Previous studies have demonstrated that SH2-containing inositol phosphatase (SHIP) is involved in the control of B cell, myeloid cell and macrophage activation and proliferation. The goal of the present study was to examine the role of SHIP during proliferation and apoptosis in cells of the

  7. Up-regulation of eEF1A2 promotes proliferation and inhibits apoptosis in prostate cancer

    International Nuclear Information System (INIS)

    Sun, Yue; Du, Chengli; Wang, Bo; Zhang, Yanling; Liu, Xiaoyan; Ren, Guoping

    2014-01-01

    Highlights: • The expression of eEF1A2 is up-regulated in prostate cancer tissues. • Suppression of eEF1A2 inhibits the proliferation and promotes apoptosis. • Inhibition of eEF1A2 enhances the expression of apoptotic relevant proteins. • The expressions of eEF1A2 and cleavage-caspase3 are inversely correlated. - Abstract: Background: eEF1A2 is a protein translation factor involved in protein synthesis, which possesses important function roles in cancer development. This study aims at investigating the expression pattern of eEF1A2 in prostate cancer and its potential role in prostate cancer development. Methods: We examined the expression level of eEF1A2 in 30 pairs of prostate cancer tissues by using RT-PCR and immunohistochemical staining (IHC). Then we applied siRNA specifically targeting eEF1A2 to down-regulate its expression in DU-145 and PC-3 cells. Flow cytometer was used to explore apoptosis and Western-blot was used to detect the pathway proteins of apoptosis. Results: Our results showed that the expression level of eEF1A2 in prostate cancer tissues was significantly higher compared to their corresponding normal tissues. Reduction of eEF1A2 expression in DU-145 and PC-3 cells led to a dramatic inhibition of proliferation accompanied with enhanced apoptosis rate. Western blot revealed that apoptosis pathway proteins (caspase3, BAD, BAX, PUMA) were significantly up-regulated after suppression of eEF1A2. More importantly, the levels of eEF1A2 and caspase3 were inversely correlated in prostate cancer tissues. Conclusion: Our data suggests that eEF1A2 plays an important role in prostate cancer development, especially in inhibiting apoptosis. So eEF1A2 might serve as a potential therapeutic target in prostate cancer

  8. Patterns of Apoptosis and Proliferation throughout the Biennial Reproductive Cycle of Viviparous Female Typhlonectes compressicauda (Amphibia, Gymnophiona

    Directory of Open Access Journals (Sweden)

    Michel Raquet

    2016-12-01

    Full Text Available Typhlonectes compressicauda is an aquatic gymnophionan amphibian living in South America. Its breeding cycle is linked to seasons, characterized by a regular alternation of rainy and dry seasons. During a complex biennial cycle, the female genital tract undergoes a series of alternations of increasing and decreasing, governed by equilibrium of proliferation and apoptotic phenomena. Immunohistochemical methods were used to visualize cell proliferation with the detection of Ki67 antibody, a protein present in proliferative cells; terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL and Apostain were performed to detect apoptotic cells on sections of ovaries and oviducts. In ovaries, both phenomena affect the germinal nests and follicles according to the cycle period. In the oviduct, the balance was in favor of proliferation during preparation for reproduction, and in favor of apoptosis when genital ducts regress. Apoptosis and proliferation are narrowly implicated in the remodeling of the genital tract and they are accompanied by the differentiation of tissues according to the phase of the breeding cycle. These variations permit the capture of oocytes at ovulation, always at the same period, and the parturition after 6–7 months of gestation, at a period in which the newborns live with their mother, protected in burrows in the mud. During the intervening year of sexual inactivity, the female reconstitutes body reserves.

  9. Inositol Hexaphosphate Inhibits Proliferation and Induces Apoptosis of Colon Cancer Cells by Suppressing the AKT/mTOR Signaling Pathway

    Directory of Open Access Journals (Sweden)

    Małgorzata Kapral

    2017-10-01

    Full Text Available Abstract: AKT, a serine/threonine protein kinase and mammalian target of rapamycin (mTOR plays a critical role in the proliferation and resistance to apoptosis that are essential to the development and progression of colon cancer. Therefore, AKT/mTOR signaling pathway has been recognized as an attractive target for anticancer therapy. Inositol hexaphosphate (InsP6, a natural occurring phytochemical, has been shown to have both preventive and therapeutic effects against various cancers, however, its exact molecular mechanisms of action are not fully understood. The aim of the in vitro study was to investigate the anticancer activity of InsP6 on colon cancer with the focus on inhibiting the AKT1 kinase and p70S6K1 as mTOR effector, in relation to proliferation and apoptosis of cells. The colon cancer Caco-2 cells were cultured using standard techniques and exposed to InsP6 at different concentrations (1 mM, 2.5 mM and 5 mM. Cellular proliferative activity was monitored by 5-bromo-2′-deoxyuridine (BrdU incorporation into cellular DNA. Flow cytometric analysis was performed for cell cycle progression and apoptosis studies. Real-time RT-qPCR was used to validate mRNA levels of CDNK1A, CDNK1B, CASP3, CASP9, AKT1 and S6K1 genes. The concentration of p21 protein as well as the activities of caspase 3, AKT1 and p70S6K1 were determined by the ELISA method. The results revealed that IP6 inhibited proliferation and stimulated apoptosis of colon cancer cells. This effect was mediated by an increase in the expression of genes encoding p21, p27, caspase 3, caspase 9 as well a decrease in transcription of AKT1 and S6K1. InsP6 suppressed phosphorylation of AKT1 and p70S6K1, downstream effector of mTOR. Based on these studies it may be concluded that InsP6 can reduce proliferation and induce apoptosis through inhibition of the AKT/mTOR pathway and mTOR effector followed by modulation of the expression and activity of several key components of these pathways in

  10. Antioxidative Dietary Compounds Modulate Gene Expression Associated with Apoptosis, DNA Repair, Inhibition of Cell Proliferation and Migration

    Directory of Open Access Journals (Sweden)

    Likui Wang

    2014-09-01

    Full Text Available Many dietary compounds are known to have health benefits owing to their antioxidative and anti-inflammatory properties. To determine the molecular mechanism of these food-derived compounds, we analyzed their effect on various genes related to cell apoptosis, DNA damage and repair, oxidation and inflammation using in vitro cell culture assays. This review further tests the hypothesis proposed previously that downstream products of COX-2 (cyclooxygenase-2 called electrophilic oxo-derivatives induce antioxidant responsive elements (ARE, which leads to cell proliferation under antioxidative conditions. Our findings support this hypothesis and show that cell proliferation was inhibited when COX-2 was down-regulated by polyphenols and polysaccharides. Flattened macrophage morphology was also observed following the induction of cytokine production by polysaccharides extracted from viili, a traditional Nordic fermented dairy product. Coix lacryma-jobi (coix polysaccharides were found to reduce mitochondrial membrane potential and induce caspase-3- and 9-mediated apoptosis. In contrast, polyphenols from blueberries were involved in the ultraviolet-activated p53/Gadd45/MDM2 DNA repair system by restoring the cell membrane potential. Inhibition of hypoxia-inducible factor-1 by saponin extracts of ginsenoside (Ginsen and Gynostemma and inhibition of S100A4 by coix polysaccharides inhibited cancer cell migration and invasion. These observations suggest that antioxidants and changes in cell membrane potential are the major driving forces that transfer signals through the cell membrane into the cytosol and nucleus, triggering gene expression, changes in cell proliferation and the induction of apoptosis or DNA repair.

  11. Anti-inflammatory drugs suppress proliferation and induce apoptosis through altering expressions of cell cycle regulators and pro-apoptotic factors in cultured human osteoblasts

    International Nuclear Information System (INIS)

    Chang, J.-K.; Li, C.-J.; Liao, H.-J.; Wang, C.-K.; Wang, G.-J.; Ho, M.-L.

    2009-01-01

    It has been reported that anti-inflammatory drugs (AIDs) inhibited bone repair in animal studies, and suppressed proliferation and induced cell death in rat osteoblast cultures. In this study, we further investigated the molecular mechanisms of AID effects on proliferation and cell death in human osteoblasts (hOBs). We examined the effects of dexamethasone (10 -7 and 10 -6 M), non-selective non-steroidal anti-inflammatory drugs (NSAIDs): indomethacin, ketorolac, piroxicam and diclofenac (10 -5 and 10 -4 M), and COX-2 inhibitor: celecoxib (10 -6 and 10 -5 M) on proliferation, cytotoxicity, cell death, and mRNA and protein levels of cell cycle and apoptosis-related regulators in hOBs. All the tested AIDs significantly inhibited proliferation and arrested cell cycle at G0/G1 phase in hOBs. Celecoxib and dexamethasone, but not non-selective NSAIDs, were found to have cytotoxic effects on hOB, and further demonstrated to induce apoptosis and necrosis (at higher concentration) in hOBs. We further found that indomethacin, celecoxib and dexamethasone increased the mRNA and protein expressions of p27 kip1 and decreased those of cyclin D2 and p-cdk2 in hOBs. Bak expression was increased by celecoxib and dexamethasone, while Bcl-XL level was declined only by dexamethasone. Furthermore, the replenishment of PGE1, PGE2 or PGF2α did not reverse the effects of AIDs on proliferation and expressions of p27 kip1 and cyclin D2 in hOBs. We conclude that the changes in expressions of regulators of cell cycle (p27 kip1 and cyclin D2) and/or apoptosis (Bak and Bcl-XL) by AIDs may contribute to AIDs caused proliferation suppression and apoptosis in hOBs. This effect might not relate to the blockage of prostaglandin synthesis by AIDs

  12. The sGC activator inhibits the proliferation and migration, promotes the apoptosis of human pulmonary arterial smooth muscle cells via the up regulation of plasminogen activator inhibitor-2

    International Nuclear Information System (INIS)

    Zhang, Shuai; Zou, Lihui; Yang, Ting; Yang, Yuanhua; Zhai, Zhenguo; Xiao, Fei; Wang, Chen

    2015-01-01

    Background: Different types of pulmonary hypertension (PH) share the same process of pulmonary vascular remodeling, the molecular mechanism of which is not entirely clarified by far. The abnormal biological behaviors of pulmonary arterial smooth muscle cells (PASMCs) play an important role in this process. Objectives: We investigated the regulation of plasminogen activator inhibitor-2 (PAI-2) by the sGC activator, and explored the effect of PAI-2 on PASMCs proliferation, apoptosis and migration. Methods: After the transfection with PAI-2 overexpression vector and specific siRNAs or treatment with BAY 41-2272 (an activator of sGC), the mRNA and protein levels of PAI-2 in cultured human PASMCs were detected, and the proliferation, apoptosis and migration of PASMCs were investigated. Results: BAY 41-2272 up regulated the endogenous PAI-2 in PASMCs, on the mRNA and protein level. In PAI-2 overexpression group, the proliferation and migration of PASMCs were inhibited significantly, and the apoptosis of PASMCs was increased. In contrast, PAI-2 knockdown with siRNA increased PASMCs proliferation and migration, inhibited the apoptosis. Conclusions: PAI-2 overexpression inhibits the proliferation and migration and promotes the apoptosis of human PASMCs. Therefore, sGC activator might alleviate or reverse vascular remodeling in PH through the up-regulation of PAI-2. - Highlights: • sGC activator BAY41-2272 up regulated PAI-2 in PASMCs, on the mRNA and protein level. • PAI-2 overexpression inhibits the proliferation and migration of human PASMCs. • PAI-2 overexpression promotes the apoptosis of human PASMCs. • sGC activator might alleviate the vascular remodeling in pulmonary hypertension

  13. The sGC activator inhibits the proliferation and migration, promotes the apoptosis of human pulmonary arterial smooth muscle cells via the up regulation of plasminogen activator inhibitor-2

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Shuai [Beijing Institute of Respiratory Medicine, Beijing Chao-yang Hospital, Capital Medical University, 8 Gongti South Rd, Beijing (China); Beijing Key Laboratory of Respiratory and Pulmonary Circulation Disorders, 8 Gongti South Rd, Beijing (China); Zou, Lihui [Institute of Geriatrics, Beijing Hospital, 1 Dahua Rd, Beijing (China); National Clinical Research Center for Respiratory Diseases, 1 Dahua Rd, Beijing (China); Yang, Ting; Yang, Yuanhua; Zhai, Zhenguo [Beijing Institute of Respiratory Medicine, Beijing Chao-yang Hospital, Capital Medical University, 8 Gongti South Rd, Beijing (China); Beijing Key Laboratory of Respiratory and Pulmonary Circulation Disorders, 8 Gongti South Rd, Beijing (China); Xiao, Fei [Institute of Geriatrics, Beijing Hospital, 1 Dahua Rd, Beijing (China); National Clinical Research Center for Respiratory Diseases, 1 Dahua Rd, Beijing (China); Wang, Chen, E-mail: chenwangcjfh@163.com [Beijing Institute of Respiratory Medicine, Beijing Chao-yang Hospital, Capital Medical University, 8 Gongti South Rd, Beijing (China); Beijing Key Laboratory of Respiratory and Pulmonary Circulation Disorders, 8 Gongti South Rd, Beijing (China); National Clinical Research Center for Respiratory Diseases, 1 Dahua Rd, Beijing (China)

    2015-03-15

    Background: Different types of pulmonary hypertension (PH) share the same process of pulmonary vascular remodeling, the molecular mechanism of which is not entirely clarified by far. The abnormal biological behaviors of pulmonary arterial smooth muscle cells (PASMCs) play an important role in this process. Objectives: We investigated the regulation of plasminogen activator inhibitor-2 (PAI-2) by the sGC activator, and explored the effect of PAI-2 on PASMCs proliferation, apoptosis and migration. Methods: After the transfection with PAI-2 overexpression vector and specific siRNAs or treatment with BAY 41-2272 (an activator of sGC), the mRNA and protein levels of PAI-2 in cultured human PASMCs were detected, and the proliferation, apoptosis and migration of PASMCs were investigated. Results: BAY 41-2272 up regulated the endogenous PAI-2 in PASMCs, on the mRNA and protein level. In PAI-2 overexpression group, the proliferation and migration of PASMCs were inhibited significantly, and the apoptosis of PASMCs was increased. In contrast, PAI-2 knockdown with siRNA increased PASMCs proliferation and migration, inhibited the apoptosis. Conclusions: PAI-2 overexpression inhibits the proliferation and migration and promotes the apoptosis of human PASMCs. Therefore, sGC activator might alleviate or reverse vascular remodeling in PH through the up-regulation of PAI-2. - Highlights: • sGC activator BAY41-2272 up regulated PAI-2 in PASMCs, on the mRNA and protein level. • PAI-2 overexpression inhibits the proliferation and migration of human PASMCs. • PAI-2 overexpression promotes the apoptosis of human PASMCs. • sGC activator might alleviate the vascular remodeling in pulmonary hypertension.

  14. Hematopoietic Substrate-1-Associated Protein X-1 Regulates the Proliferation and Apoptosis of Endothelial Progenitor Cells Through Akt Pathway Modulation.

    Science.gov (United States)

    Guo, Xin-Bin; Deng, Xin; Wei, Ying

    2018-03-01

    Endothelial precursor cells (EPCs) are involved in vasculogenesis of various physiological and pathological processes. The proliferation and survival mechanism of EPCs needs to be explored further for the purpose of developing an effective glioma treatment. Hematopoietic substrate-1-associated protein X-1 (HAX-1) has been reported as an anti-apoptotic protein that plays an important role in several malignant tumors. However, the effect and mechanism of HAX-1 on EPCs remains unknown. This study aims to investigate the effect of HAX-1 on the proliferation and apoptosis of EPCs and explore its mechanism. According to our results, HAX-1 was overexpressed in EPCs. The results of clone formation and 5-ethynyl-2'-deoxyuridine proliferation assay showed that HAX-1 promoted multiplication of EPCs. Flow cytometry showed HAX-1 knockout cell cycle arrest mainly in G0/G1 phase. Apoptosis analysis showed that HAX-1 could protect EPCs from apoptosis in oxidative stress. Western blot assay indicated that HAX-1 could inhibit the activation of caspase cascade and reduce the expression of p21, Bcl-2-associated X protein, and p53. HAX-1 also enhanced the degradation rate and ubiquitination of p53 through the promotion of phosphorylation of proteins MDM-2 and Akt1. Co-immunoprecipitation and immunofluorescent colocalization assays were performed to test the influence of HAX-1 on the interaction between Akt1 and heat shock protein 90 (Hsp90), which is crucial for the activity of Akt1. In conclusion, this novel study suggests that HAX-1 could facilitate the Akt1 pathway through Hsp90, which led to a decline in the levels of p53, and finally promoted the proliferation and inhibited the apoptosis of EPCs. Stem Cells 2018;36:406-419. © 2017 AlphaMed Press.

  15. Differential protein expression, DNA binding and interaction with SV40 large tumour antigen implicate the p63-family of proteins in replicative senescence.

    Science.gov (United States)

    Djelloul, Siham; Tarunina, Marina; Barnouin, Karin; Mackay, Alan; Jat, Parmjit S

    2002-02-07

    P53 activity plays a key role in mammalian cells when they undergo replicative senescence at their Hayflick limit. To determine whether p63 proteins, members of the family of p53-related genes, are also involved in this process, we examined their expression in serially passaged rat embryo fibroblasts. Upon senescence, two truncated DeltaNp63 proteins decreased in abundance whereas two TAp63 isoforms accumulated. 2-D gel analysis showed that the DeltaNp63 proteins underwent post-translational modifications in both proliferating and senescent cells. Direct binding of DeltaNp63 proteins to a p53 consensus motif was greater in proliferating cells than senescent cells. In contrast p63alpha isoforms bound to DNA in a p53 dependent manner and this was higher in senescent cells than proliferating cells. An interaction of p63alpha proteins with SV40 large tumour antigen was also detected and ectopic expression of DeltaNp63alpha can extend the lifespan of rat embryo fibroblasts. Taken together the results indicate that p63 proteins may play a role in replicative senescence either by competition for p53 DNA binding sites or by direct interaction with p53 protein bound to DNA.

  16. Polydatin inhibits cell proliferation and induces apoptosis in laryngeal cancer and HeLa cells via suppression of the PDGF/AKT signaling pathway.

    Science.gov (United States)

    Li, Haixia; Shi, Baoyuan; Li, Yanyun; Yin, Fengfang

    2017-07-01

    Polydatin (PD), a stilbene compound extracted from Polygonum cuspidatum, is suggested to possess anti-cancer activities, including inhibition of cell proliferation, cell cycle arrest, and induction of apoptosis. The platelet-derived growth factor (PDGF)/AKT signaling pathway plays complex roles in tumor suppression. However, the effect of PD on the PDGF/AKT signaling pathway in laryngeal cancer and HeLa cells has not been explored. MTT assay and flow cytometry showed that PD inhibited cell proliferation and induced apoptosis in Hep-2 and AMC-HN-8 cells. Western blot analysis indicated that PD inhibited the expression levels of PDGF-B and phosphorylated AKT (p-AKT) in both cells. Treatment of PDGF-B siRNA or PDGFR inhibitor found that after the PDGF signaling was inactivated, p-AKT expression was significantly decreased in Hep-2 cells. Tumor xenograft experiment in nude mice indicated PD significantly inhibited the growth of Hep-2 cells in vivo. In conclusion, PD inhibited cell proliferation and induced apoptosis in laryngeal cancer and HeLa cells via inactivation of the PDGF/AKT signaling pathway. © 2017 Wiley Periodicals, Inc.

  17. Effects of cIAP-1, cIAP-2 and XIAP triple knockdown on prostate cancer cell susceptibility to apoptosis, cell survival and proliferation.

    LENUS (Irish Health Repository)

    Gill, Catherine

    2009-01-01

    BACKGROUND: Manipulating apoptotic resistance represents an important strategy for the treatment of hormone refractory prostate cancer. We hypothesised that the Inhibitor of Apoptosis (IAP) Proteins may be mediating this resistance and knockdown of cIAP-1, cIAP-2 and XIAP would increase sensitivity to apoptosis. METHODS: cIAP-1, cIAP-2 and XIAP where knocked down either individually or in combination using siRNA in androgen independent prostate cancer PC-3 cells as confirmed by real-time PCR and western blotting. Cells were then treated with TRAIL, Etoposide, or Tunicamycin, and apoptosis assessed by PI DNA staining. Apoptosis was confirmed with Annexin V labelling and measurement of PARP cleavage, and was inhibited using the pan-caspase inhibitor, zVAD.fmk. Clonogenic assays and assessment of ID-1 expression by western blotting were used to measure recovery and proliferation. RESULTS: PC-3 are resistant to TRAIL induced apoptosis and have elevated expression of cIAP-1, cIAP-2 and XIAP. Combined knockdown sensitised PC-3 to TRAIL induced apoptosis, but not to Etoposide or Tunicmycin, with corresponding increases in caspase activity and PARP cleavage which was inhibited by ZVAD.fmk. Triple knock down decreased proliferation which was confirmed by decreased ID-1 expression. CONCLUSION: Simultaneous knock down of the IAPs not only sensitised the PC-3 to TRAIL but also inhibited their proliferation rates and clonogenic survival. The inability to alter sensitivity to other triggers of apoptosis suggests that this effect is specific for death receptor pathways and knock down might facilitate immune-surveillance mechanisms to counter cancer progression and, in combination with therapeutic approaches using TRAIL, could represent an important treatment strategy.

  18. Effects of cIAP-1, cIAP-2 and XIAP triple knockdown on prostate cancer cell susceptibility to apoptosis, cell survival and proliferation

    Directory of Open Access Journals (Sweden)

    Dowling Catherine

    2009-06-01

    Full Text Available Abstract Background Manipulating apoptotic resistance represents an important strategy for the treatment of hormone refractory prostate cancer. We hypothesised that the Inhibitor of Apoptosis (IAP Proteins may be mediating this resistance and knockdown of cIAP-1, cIAP-2 and XIAP would increase sensitivity to apoptosis. Methods cIAP-1, cIAP-2 and XIAP where knocked down either individually or in combination using siRNA in androgen independent prostate cancer PC-3 cells as confirmed by real-time PCR and western blotting. Cells were then treated with TRAIL, Etoposide, or Tunicamycin, and apoptosis assessed by PI DNA staining. Apoptosis was confirmed with Annexin V labelling and measurement of PARP cleavage, and was inhibited using the pan-caspase inhibitor, zVAD.fmk. Clonogenic assays and assessment of ID-1 expression by western blotting were used to measure recovery and proliferation. Results PC-3 are resistant to TRAIL induced apoptosis and have elevated expression of cIAP-1, cIAP-2 and XIAP. Combined knockdown sensitised PC-3 to TRAIL induced apoptosis, but not to Etoposide or Tunicmycin, with corresponding increases in caspase activity and PARP cleavage which was inhibited by ZVAD.fmk. Triple knock down decreased proliferation which was confirmed by decreased ID-1 expression. Conclusion Simultaneous knock down of the IAPs not only sensitised the PC-3 to TRAIL but also inhibited their proliferation rates and clonogenic survival. The inability to alter sensitivity to other triggers of apoptosis suggests that this effect is specific for death receptor pathways and knock down might facilitate immune-surveillance mechanisms to counter cancer progression and, in combination with therapeutic approaches using TRAIL, could represent an important treatment strategy.

  19. Downregulation of B-myb promotes senescence via the ROS-mediated p53/p21 pathway, in vascular endothelial cells.

    Science.gov (United States)

    Zhou, Zhihui; Yin, Yanlin; Chang, Qun; Sun, Guanqun; Lin, Jiahui; Dai, Yalei

    2017-04-01

    To reveal whether B-myb is involved in preventing senescence of vascular endothelial cells, and if so, to identify possible mechanisms for it. C57/BL6 male mice and primary human aortic endothelial cells (HAECs) were used. Bleomycin was applied to induce stress-related premature senescence. B-myb knockdown was achieved using an siRNA technique and cell senescence was assessed using the senescence-associated β-galactosidase (SA-β-gal) assay. Intracellular reactive oxygen species (ROS) production was analysed using an ROS assay kit and cell proliferation was evaluated using KFluor488 EdU kit. Capillary tube network formation was determined by Matrigel assay. Expressions of mRNA and protein levels were detected by real-time PCR and western blotting. B-myb expression significantly decreased, while p53 and p21 expressions increased in the aortas of aged mice. This expression pattern was also found in replicative senescent HAECs and senescent HAECs induced by bleomycin. B-myb knockdown resulted in upregulation of p22 phox , ROS accumulation and cell senescence of HAECs. Downregulation of B-myb significantly inhibited cell proliferation and capillary tube network formation and activated the p53/p21 signalling pathway. Blocking ROS production or inhibiting p53 activation remarkably attenuated SA-β-gal activity and delayed cell senescence induced by B-myb-silencing. Downregulation of B-myb induced senescence by upregulation of p22 phox and activation of the ROS/p53/p21 pathway, in our vascular endothelial cells, suggesting that B-myb may be a novel candidate for regulating cell senescence to protect against endothelial senescence-related cardiovascular diseases. © 2016 John Wiley & Sons Ltd.

  20. Exposure to low level GSM 935 MHz radiofrequency fields does not induce apoptosis in proliferating or differentiated murine neuroblastoma cells

    International Nuclear Information System (INIS)

    Moquet, J.; Ainsbury, E.; Bouffler, S.; Lloyd, D.

    2008-01-01

    The aim of this study was to investigate whether radiofrequency (RF) fields characteristic of mobile phones at non-thermal levels can induce apoptosis in murine neuroblastoma (N2a) cells in both proliferating and differentiated states. Cells were exposed continuously for 24 h to one of the three 935-MHz RF signals: global system for mobile communication (GSM) basic, GSM talk and a continuous wave, unmodulated signal; all at a specific energy absorption rate of 2 W kg -1 . The measured increase in temperature of the cells due to the RF fields was around 0.06 deg. C. At a number of time points between 0 and 48 h post-exposure, the cells were assessed for apoptosis under a fluorescence microscope using three independent assays: Annexin V, caspase activation and in situ end-labelling. No statistically significant differences in apoptosis levels were observed between the exposed and sham-exposed cells using the three assays at any time point post-exposure. These data suggest that RF exposures, characteristic of GSM mobile phones, do not significantly affect the apoptosis levels in proliferating and differentiated murine neuroblastoma cell line N2a. (authors)

  1. Knockdown of human deubiquitinase PSMD14 induces cell cycle arrest and senescence

    Energy Technology Data Exchange (ETDEWEB)

    Byrne, Ann; McLaren, Rajashree P.; Mason, Paul; Chai, Lilly; Dufault, Michael R.; Huang, Yinyin; Liang, Beirong; Gans, Joseph D.; Zhang, Mindy; Carter, Kara; Gladysheva, Tatiana B.; Teicher, Beverly A.; Biemann, Hans-Peter N.; Booker, Michael; Goldberg, Mark A.; Klinger, Katherine W.; Lillie, James [Genzyme Corporation, 49 New York Avenue, Framingham, MA 01701 (United States); Madden, Stephen L., E-mail: steve.madden@genzyme.com [Genzyme Corporation, 49 New York Avenue, Framingham, MA 01701 (United States); Jiang, Yide, E-mail: yide.jiang@genzyme.com [Genzyme Corporation, 49 New York Avenue, Framingham, MA 01701 (United States)

    2010-01-15

    The PSMD14 (POH1, also known as Rpn11/MPR1/S13/CepP1) protein within the 19S complex (19S cap; PA700) is responsible for substrate deubiquitination during proteasomal degradation. The role of PSMD14 in cell proliferation and senescence was explored using siRNA knockdown in carcinoma cell lines. Our results reveal that down-regulation of PSMD14 by siRNA transfection had a considerable impact on cell viability causing cell arrest in the G0-G1 phase, ultimately leading to senescence. The molecular events associated with decreased cell proliferation, cell cycle arrest and senescence include down-regulation of cyclin B1-CDK1-CDC25C, down-regulation of cyclin D1 and up-regulation of p21{sup /Cip} and p27{sup /Kip1}. Most notably, phosphorylation of the retinoblastoma protein was markedly reduced in PSMD14 knockdown cells. A comparative study with PSMB5, a subunit of the 20S proteasome, revealed that PSMB5 and PSMD14 have different effects on cell cycle, senescence and associated molecular events. These data support the view that the 19S and 20S subunits of the proteasome have distinct biological functions and imply that targeting 19S and 20S would have distinct molecular consequences on tumor cells.

  2. MicroRNA-200a-3p suppresses tumor proliferation and induces apoptosis by targeting SPAG9 in renal cell carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xinsheng; Jiang, Fuquan; Song, Haitao; Li, Xu; Xian, Jiantao; Gu, Xinquan, E-mail: guxqprofessor@163.com

    2016-02-12

    Sperm-associated antigen 9(SPAG9), as a well-recognized oncogene protein, has a critical effect on renal cell carcinoma (RCC) progression. Our study tried to explore the mediator of miR-200a-3p, a tumor suppressing miRNA on SPAG9 expression and renal cell proliferation and apoptosis. We found the expression of miR-200a-3p was significantly lower in RCC specimens. Based on in vitro assays, we found miR-200a-3p significantly inhibit cancer cell proliferation by inducing apoptosis. In addition, our study uncovered that miR-200a-3p directly regulates oncogenic SPAG9 in 786-O and ACHN cells. Silencing of SPAG9 resulted in significantly decreased in the growth and the cell cycle of the renal cancer cell lines. Understanding of oncogenic SPAG9 regulated by miR-200a-3p might be beneficial to reveal new therapeutic targets for RCC. - Highlights: • MiR-200a-3p is downregulated in renal cell carcinoma. • MiR-200a-3p regulates cell proliferation through inducing apoptosis. • MiR-200a-3p is involved in cell cycle regulation. • SPAG9 is a potential target of miR-200a-3p.

  3. Oxidative Stress Induces Endothelial Cell Senescence via Downregulation of Sirt6

    Directory of Open Access Journals (Sweden)

    Rong Liu

    2014-01-01

    Full Text Available Accumulating evidence has shown that diabetes accelerates aging and endothelial cell senescence is involved in the pathogenesis of diabetic vascular complications, including diabetic retinopathy. Oxidative stress is recognized as a key factor in the induction of endothelial senescence and diabetic retinopathy. However, specific mechanisms involved in oxidative stress-induced endothelial senescence have not been elucidated. We hypothesized that Sirt6, which is a nuclear, chromatin-bound protein critically involved in many pathophysiologic processes such as aging and inflammation, may have a role in oxidative stress-induced vascular cell senescence. Measurement of Sirt6 expression in human endothelial cells revealed that H2O2 treatment significantly reduced Sirt6 protein. The loss of Sirt6 was associated with an induction of a senescence phenotype in endothelial cells, including decreased cell growth, proliferation and angiogenic ability, and increased expression of senescence-associated β-galactosidase activity. Additionally, H2O2 treatment reduced eNOS expression, enhanced p21 expression, and dephosphorylated (activated retinoblastoma (Rb protein. All of these alternations were attenuated by overexpression of Sirt6, while partial knockdown of Sirt6 expression by siRNA mimicked the effect of H2O2. In conclusion, these results suggest that Sirt6 is a critical regulator of endothelial senescence and oxidative stress-induced downregulation of Sirt6 is likely involved in the pathogenesis of diabetic retinopathy.

  4. Long Non-Coding RNA TUG1 Promotes Proliferation and Inhibits Apoptosis of Osteosarcoma Cells by Sponging miR-132-3p and Upregulating SOX4 Expression.

    Science.gov (United States)

    Li, Gang; Liu, Keyu; Du, Xinhui

    2018-03-01

    Long non-coding RNA taurine upregulated gene 1 (TUG1) is reported to be a vital regulator of the progression of various cancers. This study aimed to explore the exact roles and molecular mechanisms of TUG1 in osteosarcoma (OS) development. Real-time quantitative PCR was applied to detect the expressions of TUG1 and microRNA-132-3p (miR-132-3p) in OS tissues and cells. Western blot was performed to measure protein levels of sex determining region Y-box 4 (SOX4). Cell viability was assessed using XTT assay. Cell apoptosis was evaluated using flow cytometry and caspase-3 activity detection assays. Bioinformatics analysis and luciferase reporter experiments were employed to confirm relationships among TUG1, miR-132-3p, and SOX4. TUG1 was highly expressed in human OS tissues, OS cell lines, and primary OS cells. TUG1 knockdown hindered proliferation and induced apoptosis in human OS cell lines and primary OS cells. Moreover, TUG1 inhibited miR-132-3p expression by direct interaction, and introduction of miR-132-3p inhibitor partly abrogated the effect of TUG1 knockdown on the proliferation and apoptosis of OS cells. Furthermore, SOX4 was validated as a target of miR-132-3p. Further functional analyses revealed that miR-132-3p inhibited proliferation and induced apoptosis of OS cells, while this effect was greatly abated following SOX4 overexpression. Moreover, TUG1 knockdown suppressed proliferation and promoted apoptosis by upregulating miR-132-3p and downregulating SOX4 in primary OS cells. TUG1 facilitated proliferation and suppressed apoptosis by regulating the miR-132-3p/SOX4 axis in human OS cell lines and primary OS cells. This finding provides a potential target for OS therapy. © Copyright: Yonsei University College of Medicine 2018

  5. Downregulation of long noncoding RNA TUG1 inhibits proliferation and induces apoptosis through the TUG1/miR-142/ZEB2 axis in bladder cancer cells.

    Science.gov (United States)

    Liu, Qian; Liu, Hui; Cheng, Hepeng; Li, Yang; Li, Xiaodong; Zhu, Chaoyang

    2017-01-01

    Bladder cancer is a common serious disease around the world. Long noncoding RNAs (lncRNAs) have been demonstrated to participate in the development and progression of various cancers, including bladder cancer. The aim of this study was to investigate the effects of lncRNA taurine upregulated gene 1 (TUG1) on proliferation and apoptosis in bladder cancer cell lines and the underlying mechanism. The levels of TUG1 were detected by quantitative real time polymerase chain reaction (qRT-PCR) in bladder cancer tissues and cells. The mRNA and protein levels of zinc finger E-box binding homeobox 2 (ZEB2) were measured by qRT-PCR and Western blot analysis, respectively. The functional targets of TUG1 were predicted by online softwares and confirmed by luciferase reporter assay. The effects of TUG1 on cell proliferation and apoptosis were examined by MTT and apoptosis assay, respectively. The expression levels of β-catenin, cyclinD1, and c-Myc in T24 cells were determined by Western blot analysis. The levels of TUG1 and ZEB2 were significantly increased in bladder cancer tissues and cells. Knockdown of either TUG1 or ZEB2 inhibited proliferation and induced apoptosis in bladder cancer cells. Interestingly, ZEB2 overexpression reversed the effects of TUG1 knockdown on cell proliferation and apoptosis. Moreover, ZEB2 was verified as a direct target of miR-142 and miR-142 could specially bind to TUG1. In addition, downregulation of TUG1 inhibited the Wnt/β-catenin pathway by regulating ZEB2 expression in bladder cancer cells. Downregulation of TUG1 expression inhibited proliferation and induced apoptosis in bladder cancer cells by targeting ZEB2 mediated by miR-142 through the inactivation of Wnt/β-catenin pathway.

  6. Escherichia coli producing colibactin triggers premature and transmissible senescence in mammalian cells.

    Directory of Open Access Journals (Sweden)

    Thomas Secher

    Full Text Available Cellular senescence is an irreversible state of proliferation arrest evoked by a myriad of stresses including oncogene activation, telomere shortening/dysfunction and genotoxic insults. It has been associated with tumor activation, immune suppression and aging, owing to the secretion of proinflammatory mediators. The bacterial genotoxin colibactin, encoded by the pks genomic island is frequently harboured by Escherichia coli strains of the B2 phylogenetic group. Mammalian cells exposed to live pks+ bacteria exhibit DNA-double strand breaks (DSB and undergo cell-cycle arrest and death. Here we show that cells that survive the acute bacterial infection with pks+ E. coli display hallmarks of cellular senescence: chronic DSB, prolonged cell-cycle arrest, enhanced senescence-associated β-galactosidase (SA-β-Gal activity, expansion of promyelocytic leukemia nuclear foci and senescence-associated heterochromatin foci. This was accompanied by reactive oxygen species production and pro-inflammatory cytokines, chemokines and proteases secretion. These mediators were able to trigger DSB and enhanced SA-β-Gal activity in bystander recipient cells treated with conditioned medium from senescent cells. Furthermore, these senescent cells promoted the growth of human tumor cells. In conclusion, the present data demonstrated that the E. coli genotoxin colibactin induces cellular senescence and subsequently propel bystander genotoxic and oncogenic effects.

  7. Donkey milk kefir induces apoptosis and suppresses proliferation of Ehrlich ascites carcinoma by decreasing iNOS in mice.

    Science.gov (United States)

    Esener, Obb; Balkan, B M; Armutak, E I; Uvez, A; Yildiz, G; Hafizoglu, M; Yilmazer, N; Gurel-Gurevin, E

    2018-04-12

    Donkey milk and donkey milk kefir exhibit antiproliferative, antimutagenic and antibacterial effects. We investigated the effects of donkey milk and donkey milk kefir on oxidative stress, apoptosis and proliferation in Ehrlich ascites carcinoma (EAC) in mice. Thirty-four adult male Swiss albino mice were divided into four groups as follows: group 1, administered 0.5 ml water; group 2, administered 0.5 ml water + EAC cells; group 3, administered 0.5 ml donkey milk + EAC cells; group 4, administered 0.5 ml donkey milk kefir + EAC cells. We introduced 2.5 x 10 6 EAC cells into each animal by subcutaneous injection. Tap water, donkey milk and donkey milk kefir were administered by gavage for 10 days. Animals were sacrificed on day 11. After measuring the short and long diameters of the tumors, tissues were processed for histology. To determine oxidative stress, cell death and proliferation iNOS and eNOS, active caspase-3 and proliferating cell nuclear antigen were assessed using immunohistochemistry. A TUNEL assay also was used to detect apoptosis. Tumor volume decreased in the donkey milk kefir group compared to the control and donkey milk groups. Tumor volume increased in the donkey milk group compared to the control group. Proliferating cell nuclear antigen levels were higher in the donkey milk kefir group compared to the control and donkey milk groups. The number of apoptotic cells was less in the donkey milk group, compared to the control, whereas it was highest in the donkey milk kefir group. Donkey milk administration increased eNOS levels and decreased iNOS levels, compared to the control group. In the donkey milk kefir group, iNOS levels were significantly lower than those of the control and donkey milk groups, while eNOS levels were similar to the control group. Donkey milk kefir induced apoptosis, suppressed proliferation and decreased co-expression of iNOS and eNOS. Donkey milk promoted development of the tumors. Therefore, donkey milk kefir appears to

  8. Apoptosis is increased and cell proliferation is decreased in out-of-phase endometria from infertile and recurrent abortion patients

    Directory of Open Access Journals (Sweden)

    Irigoyen Marcela

    2010-10-01

    Full Text Available Abstract Background Various endometrial abnormalities have been associated with luteal phase deficiency: a significant dyssynchrony in the maturation of the glandular epithelium and the stroma and a prevalence of out-of-phase endometrial biopsy specimens. Out-of phase endometrium is a controversial disorder related to failed implantation, infertility and early pregnancy loss. Given that the regulation of the apoptotic process in endometrium of luteal phase deficiency is still unknown, the aim of this study was to evaluate cell proliferation, apoptosis and the levels of the main effector caspase, caspase-3 in the luteal in-phase and out-of-phase endometrium. Methods Thirty-seven endometrial samples from sterile or recurrent abortion patients were included in this study: 21 in-phase samples (controls and 16 samples with out-of-phase endometrium. Biopsy specimens of eutopic endometrium were obtained from all subjects during days 21-25 of the menstrual cycle. The endometrium with endometrial maturity of cycle day 25 or less at the time of menstruation was considered out-of phase. Endometrial tissues were fixed in 10% buffered formaldehyde. For apoptosis quantification, sections were processed for in situ immunohistochemical localization of nuclei exhibiting DNA fragmentation, by the terminal deoxynucleotidyl transferase (TdT-mediated dUTP digoxygenin nick-end labeling (TUNEL technique. Expressions of Proliferating Cell Nuclear Antigen (PCNA as a marker of cell proliferation, and of cleaved caspase-3 as a marker of apoptosis, were assessed by immunohistochemistry in the luteal in-phase and out-of-phase endometrium from infertile and recurrent abortion patients. Results Luteal out-of-phase endometrium had increased apoptosis levels compared to in-phase endometrium (p Conclusions this study represents the first report describing variations at the cell proliferation and cell death levels in the out-of-phase endometrium in comparison with in

  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. N6-methyladenosine mediates the cellular proliferation and apoptosis via microRNAs in arsenite-transformed cells.

    Science.gov (United States)

    Gu, Shiyan; Sun, Donglei; Dai, Huangmei; Zhang, Zunzhen

    2018-04-20

    N 6 -methyladenosine (m 6 A) modification is implicated to play an important role in cellular biological processes, but its regulatory mechanisms in arsenite-induced carcinogenesis are largely unknown. Here, human bronchial epithelial (HBE) cells were chronically treated with 2.5 μM arsenite sodium (NaAsO 2 ) for about 13 weeks and these cells were identified with malignant phenotype which was demonstrated by increased levels of cellular proliferation, percentages of plate colony formation and soft agar clone formation, and high potential of resistance to apoptotic induction. Our results firstly demonstrated that m 6 A modification on RNA was significantly increased in arsenite-transformed cells and this modification may be synergistically regulated by methyltransferase-like 3 (METTL3), methyltransferase-like 14 (METTL14), Wilms tumor 1-associated protein (WTAP) and Fat mass and obesity-associated protein (FTO). In addition, knocking down of METTL3 in arsenite-transformed cells can dramatically reverse the malignant phenotype, which was manifested by lower percentages of clone and colony formation as well as higher rates of apoptotic induction. Given the critical roles of miRNAs in cellular proliferation and apoptosis, miRNAs regulated by m 6 A in arsenite-transformed cells were analyzed by Venn diagram and KEGG pathway in this study. The results showed that these m 6 A-mediated miRNAs can regulate pathways which are closely associated with cellular proliferation and apoptosis, implicating that these miRNAs may be the critical bridge by which m 6 A mediates dysregulation of cell survival and apoptosis in arsenite-transformed cells. Taken together, our results firstly demonstrated the significant role of m 6 A in the prevention of tumor occurrence and progression induced by arsenite. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Assessment of 16 chemicals on proliferation and apoptosis in human neuroprogenitor cells using high-content image analysis (HCA).

    Science.gov (United States)

    The need for efficient methods of screening chemicals for the potential to cause developmental neurotoxicity is paramount. We previously described optimization of an HCA assay for proliferation and apoptosis in ReNcell CX cells (ReN), identifying appropriate controls. Utility of ...

  12. The Tocotrienol-Rich Fraction Is Superior to Tocopherol in Promoting Myogenic Differentiation in the Prevention of Replicative Senescence of Myoblasts.

    Directory of Open Access Journals (Sweden)

    Shy Cian Khor

    Full Text Available Aging results in a loss of muscle mass and strength. Myoblasts play an important role in maintaining muscle mass through regenerative processes, which are impaired during aging. Vitamin E potentially ameliorates age-related phenotypes. Hence, this study aimed to determine the effects of the tocotrienol-rich fraction (TRF and α-tocopherol (ATF in protecting myoblasts from replicative senescence and promoting myogenic differentiation. Primary human myoblasts were cultured into young and senescent stages and were then treated with TRF or ATF for 24 h, followed by an analysis of cell proliferation, senescence biomarkers, cellular morphology and differentiation. Our data showed that replicative senescence impaired the normal regenerative processes of myoblasts, resulting in changes in cellular morphology, cell proliferation, senescence-associated β-galactosidase (SA-β-gal expression, myogenic differentiation and myogenic regulatory factors (MRFs expression. Treatment with both TRF and ATF was beneficial to senescent myoblasts in reclaiming the morphology of young cells, improved cell viability and decreased SA-β-gal expression. However, only TRF treatment increased BrdU incorporation in senescent myoblasts, as well as promoted myogenic differentiation through the modulation of MRFs at the mRNA and protein levels. MYOD1 and MYOG gene expression and myogenin protein expression were modulated in the early phases of myogenic differentiation. In conclusion, the tocotrienol-rich fraction is superior to α-tocopherol in ameliorating replicative senescence-related aberration and promoting differentiation via modulation of MRFs expression, indicating vitamin E potential in modulating replicative senescence of myoblasts.

  13. In Vivo Senescence in the Sbds-Deficient Murine Pancreas: Cell-Type Specific Consequences of Translation Insufficiency.

    Directory of Open Access Journals (Sweden)

    Marina E Tourlakis

    2015-06-01

    Full Text Available Genetic models of ribosome dysfunction show selective organ failure, highlighting a gap in our understanding of cell-type specific responses to translation insufficiency. Translation defects underlie a growing list of inherited and acquired cancer-predisposition syndromes referred to as ribosomopathies. We sought to identify molecular mechanisms underlying organ failure in a recessive ribosomopathy, with particular emphasis on the pancreas, an organ with a high and reiterative requirement for protein synthesis. Biallelic loss of function mutations in SBDS are associated with the ribosomopathy Shwachman-Diamond syndrome, which is typified by pancreatic dysfunction, bone marrow failure, skeletal abnormalities and neurological phenotypes. Targeted disruption of Sbds in the murine pancreas resulted in p53 stabilization early in the postnatal period, specifically in acinar cells. Decreased Myc expression was observed and atrophy of the adult SDS pancreas could be explained by the senescence of acinar cells, characterized by induction of Tgfβ, p15(Ink4b and components of the senescence-associated secretory program. This is the first report of senescence, a tumour suppression mechanism, in association with SDS or in response to a ribosomopathy. Genetic ablation of p53 largely resolved digestive enzyme synthesis and acinar compartment hypoplasia, but resulted in decreased cell size, a hallmark of decreased translation capacity. Moreover, p53 ablation resulted in expression of acinar dedifferentiation markers and extensive apoptosis. Our findings indicate a protective role for p53 and senescence in response to Sbds ablation in the pancreas. In contrast to the pancreas, the Tgfβ molecular signature was not detected in fetal bone marrow, liver or brain of mouse models with constitutive Sbds ablation. Nevertheless, as observed with the adult pancreas phenotype, disease phenotypes of embryonic tissues, including marked neuronal cell death due to apoptosis

  14. In Vivo Senescence in the Sbds-Deficient Murine Pancreas: Cell-Type Specific Consequences of Translation Insufficiency

    Science.gov (United States)

    Tourlakis, Marina E.; Zhang, Siyi; Ball, Heather L.; Gandhi, Rikesh; Liu, Hongrui; Zhong, Jian; Yuan, Julie S.; Guidos, Cynthia J.; Durie, Peter R.; Rommens, Johanna M.

    2015-01-01

    Genetic models of ribosome dysfunction show selective organ failure, highlighting a gap in our understanding of cell-type specific responses to translation insufficiency. Translation defects underlie a growing list of inherited and acquired cancer-predisposition syndromes referred to as ribosomopathies. We sought to identify molecular mechanisms underlying organ failure in a recessive ribosomopathy, with particular emphasis on the pancreas, an organ with a high and reiterative requirement for protein synthesis. Biallelic loss of function mutations in SBDS are associated with the ribosomopathy Shwachman-Diamond syndrome, which is typified by pancreatic dysfunction, bone marrow failure, skeletal abnormalities and neurological phenotypes. Targeted disruption of Sbds in the murine pancreas resulted in p53 stabilization early in the postnatal period, specifically in acinar cells. Decreased Myc expression was observed and atrophy of the adult SDS pancreas could be explained by the senescence of acinar cells, characterized by induction of Tgfβ, p15Ink4b and components of the senescence-associated secretory program. This is the first report of senescence, a tumour suppression mechanism, in association with SDS or in response to a ribosomopathy. Genetic ablation of p53 largely resolved digestive enzyme synthesis and acinar compartment hypoplasia, but resulted in decreased cell size, a hallmark of decreased translation capacity. Moreover, p53 ablation resulted in expression of acinar dedifferentiation markers and extensive apoptosis. Our findings indicate a protective role for p53 and senescence in response to Sbds ablation in the pancreas. In contrast to the pancreas, the Tgfβ molecular signature was not detected in fetal bone marrow, liver or brain of mouse models with constitutive Sbds ablation. Nevertheless, as observed with the adult pancreas phenotype, disease phenotypes of embryonic tissues, including marked neuronal cell death due to apoptosis, were determined to

  15. Mitochondrial dysfunction accounts for the stochastic heterogeneity in telomere-dependent senescence.

    Directory of Open Access Journals (Sweden)

    João F Passos

    2007-05-01

    Full Text Available Aging is an inherently stochastic process, and its hallmark is heterogeneity between organisms, cell types, and clonal populations, even in identical environments. The replicative lifespan of primary human cells is telomere dependent; however, its heterogeneity is not understood. We show that mitochondrial superoxide production increases with replicative age in human fibroblasts despite an adaptive UCP-2-dependent mitochondrial uncoupling. This mitochondrial dysfunction is accompanied by compromised [Ca(2+]i homeostasis and other indicators of a retrograde response in senescent cells. Replicative senescence of human fibroblasts is delayed by mild mitochondrial uncoupling. Uncoupling reduces mitochondrial superoxide generation, slows down telomere shortening, and delays formation of telomeric gamma-H2A.X foci. This indicates mitochondrial production of reactive oxygen species (ROS as one of the causes of replicative senescence. By sorting early senescent (SES cells from young proliferating fibroblast cultures, we show that SES cells have higher ROS levels, dysfunctional mitochondria, shorter telomeres, and telomeric gamma-H2A.X foci. We propose that mitochondrial ROS is a major determinant of telomere-dependent senescence at the single-cell level that is responsible for cell-to-cell variation in replicative lifespan.

  16. Ameliorating replicative senescence of human bone marrow stromal cells by PSMB5 overexpression

    International Nuclear Information System (INIS)

    Lu, Li; Song, Hui-Fang; Wei, Jiao-Long; Liu, Xue-Qin; Song, Wen-Hui; Yan, Ba-Yi; Yang, Gui-Jiao; Li, Ang; Yang, Wu-Lin

    2014-01-01

    Highlights: • PSMB5 overexpression restores the differentiation potential of aged hBMSCs. • PSMB5 overexpression enhances the proteasomal activity of late-stage hBMSCs. • PSMB5 overexpression inhibits replicative senescence and improved cell viability. • PSMB5 overexpression promotes cell growth by upregulating the Cyclin D1/CDK4 complex. - Abstract: Multipotent human bone marrow stromal cells (hBMSCs) potentially serve as a source for cell-based therapy in regenerative medicine. However, in vitro expansion was inescapably accompanied with cell senescence, characterized by inhibited proliferation and compromised pluripotency. We have previously demonstrated that this aging process is closely associated with reduced 20S proteasomal activity, with down-regulation of rate-limiting catalytic β-subunits particularly evident. In the present study, we confirmed that proteasomal activity directly contributes to senescence of hBMSCs, which could be reversed by overexpression of the β5-subunit (PSMB5). Knocking down PSMB5 led to decreased proteasomal activity concurrent with reduced cell proliferation in early-stage hBMSCs, which is similar to the senescent phenotype observed in late-stage cells. In contrast, overexpressing PSMB5 in late-stage cells efficiently restored the normal activity of 20S proteasomes and promoted cell growth, possibly via upregulating the Cyclin D1/CDK4 complex. Additionally, PSMB5 could enhance cell resistance to oxidative stress, as evidenced by the increased cell survival upon exposing senescent hBMSCs to hydrogen peroxide. Furthermore, PSMB5 overexpression retained the pluripotency of late-stage hBMSCs by facilitating their neural differentiation both in vitro and in vivo. Collectively, our work reveals a critical role of PSMB5 in 20S proteasome-mediated protection against replicative senescence, pointing to a possible strategy for maintaining the integrity of culture-expanded hBMSCs by manipulating the expression of PSMB5

  17. Ameliorating replicative senescence of human bone marrow stromal cells by PSMB5 overexpression

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Li, E-mail: luli7300@126.com [Department of Anatomy, Shanxi Medical University, Taiyuan 030001 (China); Song, Hui-Fang; Wei, Jiao-Long; Liu, Xue-Qin [Department of Anatomy, Shanxi Medical University, Taiyuan 030001 (China); Song, Wen-Hui [Department of Orthopaedics, The Second Affiliated Hospital of Shanxi Medical University, Taiyuan 030001 (China); Yan, Ba-Yi; Yang, Gui-Jiao [Department of Anatomy, Shanxi Medical University, Taiyuan 030001 (China); Li, Ang [Department of Medicine, University of Hong Kong Faculty of Medicine, Hong Kong (Hong Kong); Department of Anatomy, University of Hong Kong Faculty of Medicine, Hong Kong (Hong Kong); Yang, Wu-Lin, E-mail: wulinyoung@163.com [School of Biotechnology and Food Engineering, Hefei University of Technology, Hefei 230009 (China); Laboratory of Metabolic Medicine, Singapore Bioimaging Consortium (SBIC), Agency for Science, Technology and Research - A*STAR (Singapore)

    2014-01-24

    Highlights: • PSMB5 overexpression restores the differentiation potential of aged hBMSCs. • PSMB5 overexpression enhances the proteasomal activity of late-stage hBMSCs. • PSMB5 overexpression inhibits replicative senescence and improved cell viability. • PSMB5 overexpression promotes cell growth by upregulating the Cyclin D1/CDK4 complex. - Abstract: Multipotent human bone marrow stromal cells (hBMSCs) potentially serve as a source for cell-based therapy in regenerative medicine. However, in vitro expansion was inescapably accompanied with cell senescence, characterized by inhibited proliferation and compromised pluripotency. We have previously demonstrated that this aging process is closely associated with reduced 20S proteasomal activity, with down-regulation of rate-limiting catalytic β-subunits particularly evident. In the present study, we confirmed that proteasomal activity directly contributes to senescence of hBMSCs, which could be reversed by overexpression of the β5-subunit (PSMB5). Knocking down PSMB5 led to decreased proteasomal activity concurrent with reduced cell proliferation in early-stage hBMSCs, which is similar to the senescent phenotype observed in late-stage cells. In contrast, overexpressing PSMB5 in late-stage cells efficiently restored the normal activity of 20S proteasomes and promoted cell growth, possibly via upregulating the Cyclin D1/CDK4 complex. Additionally, PSMB5 could enhance cell resistance to oxidative stress, as evidenced by the increased cell survival upon exposing senescent hBMSCs to hydrogen peroxide. Furthermore, PSMB5 overexpression retained the pluripotency of late-stage hBMSCs by facilitating their neural differentiation both in vitro and in vivo. Collectively, our work reveals a critical role of PSMB5 in 20S proteasome-mediated protection against replicative senescence, pointing to a possible strategy for maintaining the integrity of culture-expanded hBMSCs by manipulating the expression of PSMB5.

  18. Knockdown of IL-8 Provoked Premature Senescence of Placenta-Derived Mesenchymal Stem Cells.

    Science.gov (United States)

    Li, Juan-Juan; Ma, Feng-Xia; Wang, You-Wei; Chen, Fang; Lu, Shi-Hong; Chi, Ying; Du, Wen-Jing; Song, Bao-Quan; Hu, Liang-Ding; Chen, Hu; Han, Zhong-Chao

    2017-06-15

    Mesenchymal stem cells (MSCs) have shown promise for use in cell therapy, and due to their tumor tropism can serve as vehicles for delivering therapeutic agents to tumor sites. Because interleukin-8 (IL-8) is known to mediate the protumor effect of MSCs, elimination of IL-8 secretion by MSCs may enhance their safety for use in cancer gene therapy. However, little is known concerning the effect of endogenously secreted IL-8 on MSCs. We performed studies using placenta-derived MSCs (PMSCs) to determine whether knockdown of IL-8 would influence their biological activity. We first verified that IL-8 and its membrane receptor CXCR2, but not CXCR1, were highly expressed in PMSCs. We then employed lentivirus-mediated small hairpin RNA interference to generate stable IL-8-silenced PMSCs, which displayed a variety of characteristic senescent phenotypes. We observed that at day 9 post-transfection, IL-8-silenced PMSCs had become larger and displayed a more flattened appearance when compared with their controls. Moreover, their proliferation, colony forming unit-fibroblast formation, adipogenic and osteogenic differentiation, and immunosuppressive potentials were significantly impaired. Enhanced senescence-associated β-galactosidase (SA-β-gal) activity and specific global gene expression profiles confirmed that IL-8 silencing evoked the senescence process in PMSCs. Increased levels of p-Akt and decreased levels of FOXO3a protein expression suggested that reactive oxygen species played a role in the initiation and maintenance of senescence in IL-8-silenced PMSCs. Notably, the majority of CXCR2 ligands were downregulated in presenescent IL-8-silenced PMSCs but upregulated in senescent cells, indicating an antagonistic pleiotropy of the IL-8/CXCR2 signaling pathway in PMSCs. This effect may promote the proliferation of young cells and accelerate senescence of old cells.

  19. γ-Tocotrienol Inhibits Proliferation and Induces Apoptosis via the Mitochondrial Pathway in Human Cervical Cancer HeLa Cells

    Directory of Open Access Journals (Sweden)

    Weili Xu

    2017-08-01

    Full Text Available γ-Tocotrienol, a kind of isoprenoid phytochemical, has antitumor activity. However, there is limited evidence that it has an effect on cervical cancer. In this study, the capacity to inhibit proliferation and induce apoptosis in human cervical cancer HeLa cells and the mechanism underlying these effects were examined. The results indicated that a γ-tocotrienol concentration over 30 μM inhibited the growth of HeLa cells with a 50% inhibitory concentration (IC50 of 46.90 ± 3.50 μM at 24 h, and significantly down-regulated the expression of proliferative cell nuclear antigen (PCNA and Ki-67. DNA flow cytometric analysis indicated that γ-tocotrienol arrested the cell cycle at G0/G1 phase and reduced the S phase in HeLa cells. γ-tocotrienol induced apoptosis of HeLa cells in a time- and dose-dependent manner. γ-tocotrienol-induced apoptosis in HeLa cells was accompanied by down-regulation of Bcl-2, up-regulation of Bax, release of cytochrome from mitochondria, activation of caspase-9 and caspase-3, and subsequent poly (ADP-ribose polymerase (PARP cleavage. These results suggested that γ-tocotrienol could significantly inhibit cell proliferation through G0/G1 cell cycle arrest, and induce apoptosis via the mitochondrial apoptotic pathway in human cervical cancer HeLa cells. Thus, our findings revealed that γ-tocotrienol may be considered as a potential agent for cervical cancer therapy.

  20. γ-Tocotrienol Inhibits Proliferation and Induces Apoptosis Via the Mitochondrial Pathway in Human Cervical Cancer HeLa Cells.

    Science.gov (United States)

    Xu, Weili; Mi, Yaqing; He, Pan; He, Shenghua; Niu, Lingling

    2017-08-04

    γ-Tocotrienol, a kind of isoprenoid phytochemical, has antitumor activity. However, there is limited evidence that it has an effect on cervical cancer. In this study, the capacity to inhibit proliferation and induce apoptosis in human cervical cancer HeLa cells and the mechanism underlying these effects were examined. The results indicated that a γ-tocotrienol concentration over 30 μM inhibited the growth of HeLa cells with a 50% inhibitory concentration (IC 50 ) of 46.90 ± 3.50 μM at 24 h, and significantly down-regulated the expression of proliferative cell nuclear antigen (PCNA) and Ki-67. DNA flow cytometric analysis indicated that γ-tocotrienol arrested the cell cycle at G0/G1 phase and reduced the S phase in HeLa cells. γ-tocotrienol induced apoptosis of HeLa cells in a time- and dose-dependent manner. γ-tocotrienol-induced apoptosis in HeLa cells was accompanied by down-regulation of Bcl-2, up-regulation of Bax, release of cytochrome from mitochondria, activation of caspase-9 and caspase-3, and subsequent poly (ADP-ribose) polymerase (PARP) cleavage. These results suggested that γ-tocotrienol could significantly inhibit cell proliferation through G0/G1 cell cycle arrest, and induce apoptosis via the mitochondrial apoptotic pathway in human cervical cancer HeLa cells. Thus, our findings revealed that γ-tocotrienol may be considered as a potential agent for cervical cancer therapy.

  1. Lovastatin-induced RhoA modulation and its effect on senescence in prostate cancer cells

    International Nuclear Information System (INIS)

    Lee, Jeeyun; Lee, Inkyoung; Park, Chaehwa; Kang, Won Ki

    2006-01-01

    Lovastatin inhibits a 3-hydroxy 3-methylglutaryl coenzyme A reductase and prevents the synthesis of cholesterol precursors, such as farnesyl pyrophosphate (FPP) and geranylgeranyl pyrophosphate (GGPP), responsible for important cell signaling in cell proliferation and migration. Recently, the anti-cancer effect of lovastatin has been suggested in various tumor types. In this study, we showed that a low dose lovastatin induced senescence and G1 cell cycle arrest in human prostate cancer cells. Addition of GGPP or mevalonate, but not FPP, prevented the lovastatin-induced G1 phase cell cycle arrest and cell senescence. We found that constitutively active RhoA (caRhoA) reversed lovastatin-induced senescence in caRhoA-transfected PC-3 cells. Thus, we postulate that modulation of RhoA may be critical in lovastatin-induced senescence in PC-3 cells

  2. Effects of 5-fluorouracil on morphology, cell cycle, proliferation, apoptosis, autophagy and ROS production in endothelial cells and cardiomyocytes.

    Directory of Open Access Journals (Sweden)

    Chiara Focaccetti

    Full Text Available Antimetabolites are a class of effective anticancer drugs interfering in essential biochemical processes. 5-Fluorouracil (5-FU and its prodrug Capecitabine are widely used in the treatment of several solid tumors (gastro-intestinal, gynecological, head and neck, breast carcinomas. Therapy with fluoropyrimidines is associated with a wide range of adverse effects, including diarrhea, dehydration, abdominal pain, nausea, stomatitis, and hand-foot syndrome. Among the 5-FU side effects, increasing attention is given to cardiovascular toxicities induced at different levels and intensities. Since the mechanisms related to 5-FU-induced cardiotoxicity are still unclear, we examined the effects of 5-FU on primary cell cultures of human cardiomyocytes and endothelial cells, which represent two key components of the cardiovascular system. We analyzed at the cellular and molecular level 5-FU effects on cell proliferation, cell cycle, survival and induction of apoptosis, in an experimental cardioncology approach. We observed autophagic features at the ultrastructural and molecular levels, in particular in 5-FU exposed cardiomyocytes. Reactive oxygen species (ROS elevation characterized the endothelial response. These responses were prevented by a ROS scavenger. We found induction of a senescent phenotype on both cell types treated with 5-FU. In vivo, in a xenograft model of colon cancer, we showed that 5-FU treatment induced ultrastructural changes in the endothelium of various organs. Taken together, our data suggest that 5-FU can affect, both at the cellular and molecular levels, two key cell types of the cardiovascular system, potentially explaining some manifestations of 5-FU-induced cardiovascular toxicity.

  3. Cyclin-dependent kinases regulate apoptosis of intestinal epithelial cells

    Science.gov (United States)

    Bhattacharya, Sujoy; Ray, Ramesh M.; Johnson, Leonard R.

    2014-01-01

    Homeostasis of the gastrointestinal epithelium is dependent upon a balance between cell proliferation and apoptosis. Cyclin-dependent kinases (Cdks) are well known for their role in cell proliferation. Previous studies from our group have shown that polyamine-depletion of intestinal epithelial cells (IEC-6) decreases cyclin-dependent kinase 2 (Cdk2) activity, increases p53 and p21Cip1 protein levels, induces G1 arrest, and protects cells from camptothecin (CPT)-induced apoptosis. Although emerging evidence suggests that members of the Cdk family are involved in the regulation of apoptosis, their roles directing apoptosis of IEC-6 cells are not known. In this study, we report that inhibition of Cdk1, 2, and 9 (with the broad range Cdk inhibitor, AZD5438) in proliferating IEC-6 cells triggered DNA damage, activated p53 signaling, inhibited proliferation, and induced apoptosis. By contrast, inhibition of Cdk2 (with NU6140) increased p53 protein and activity, inhibited proliferation, but had no effect on apoptosis. Notably, AZD5438 sensitized, whereas, NU6140 rescued proliferating IEC-6 cells from CPT-induced apoptosis. However, in colon carcinoma (Caco2) cells with mutant p53, treatment with either AZD5438 or NU6140 blocked proliferation, albeit more robustly with AZD5438. Both Cdk inhibitors induced apoptosis in Caco2 cells in a p53-independent manner. In serum starved quiescent IEC-6 cells, both AZD5438 and NU6140 decreased TNF- /CPT-induced activation of p53 and, consequently, rescued cells from apoptosis, indicating that sustained Cdk activity is required for apoptosis of quiescent cells. Furthermore, AZD5438 partially reversed the protective effect of polyamine depletion whereas NU6140 had no effect. Together, these results demonstrate that Cdks possess opposing roles in the control of apoptosis in quiescent and proliferating cells. In addition, Cdk inhibitors uncouple proliferation from apoptosis in a p53-dependent manner. PMID:24242917

  4. Activity of selenium on cell proliferation, cytotoxicity, and apoptosis and on the expression of CASP9, BCL-XL and APC in intestinal adenocarcinoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Mauro, M.O., E-mail: mari.mauro@hotmail.com [Graduate Program in Biological Sciences (Cell and Molecular Biology), Institute of Biosciences, UNESP, Rio Claro (SP) (Brazil); Sartori, Daniele [General Biology Department, State University of Londrina (UEL), Londrina (Brazil); Oliveira, Rodrigo Juliano [Coordination of Open and Distance Education, Graduate Program in Animal Science, Federal University of Mato Grosso do Sul (UFMS), Campo Grande (MS) (Brazil); Ishii, Priscila Lumi [Graduate Program in Biological Sciences (Cell and Molecular Biology), Institute of Biosciences, UNESP, Rio Claro (SP) (Brazil); Mantovani, Mario Sergio [General Biology Department, State University of Londrina (UEL), Londrina (Brazil); Ribeiro, Lucia Regina [Graduate Program in Biological Sciences (Cell and Molecular Biology), Institute of Biosciences, UNESP, Rio Claro (SP) (Brazil)

    2011-10-01

    Intestinal cancers are correlated with diet. Thus, determining and understanding nutrient-genome interactions is important. The present work assessed the action of the oligoelement selenium on cell proliferation, cytotoxicity, and in situ apoptosis induction and on the expression CASP9, BCL-XL and APC genes in intestinal adenocarcinoma cells (HT29). HT29 cells were cultured and treated with selenium at concentrations of 5, 50 and 500 ng/mL with or without the damage-inducing agent doxorubicin. These cells were then evaluated for cytotoxicity (MTT), cell proliferation and in situ apoptosis induction. To evaluate gene expression, only the cells treated with 500 ng/mL of selenium were used. RNA was extracted from these cells, and the expressions of CASP9, BCL-XL and APC were analyzed by the RT-PCR method. The GAPDH gene was used as a reference gene. The MTT assay showed that selenium was not cytotoxic at any of the concentrations tested. The cell proliferation assay showed that selenium did not interfere with cell proliferation at the three concentrations tested. In contrast, when the three concentrations were combined with doxorubicin, a significant decrease in the proliferation rate was observed. The apoptosis rate was significantly increased in the selenium (500 ng/mL) and doxorubicin group. CASP9 expression was increased and BCL-XL expression decreased in the selenium (500 ng/mL) and doxorubicin group. APC was significantly increased in the selenium group alone. These results show that selenium increases apoptosis, especially when it is associated with a damage-inducing agent. Also, selenium has an important role in the expression of the APC gene, which is related to cell cycle regulation.

  5. Activity of selenium on cell proliferation, cytotoxicity, and apoptosis and on the expression of CASP9, BCL-XL and APC in intestinal adenocarcinoma cells

    International Nuclear Information System (INIS)

    Mauro, M.O.; Sartori, Daniele; Oliveira, Rodrigo Juliano; Ishii, Priscila Lumi; Mantovani, Mario Sergio; Ribeiro, Lucia Regina

    2011-01-01

    Intestinal cancers are correlated with diet. Thus, determining and understanding nutrient-genome interactions is important. The present work assessed the action of the oligoelement selenium on cell proliferation, cytotoxicity, and in situ apoptosis induction and on the expression CASP9, BCL-XL and APC genes in intestinal adenocarcinoma cells (HT29). HT29 cells were cultured and treated with selenium at concentrations of 5, 50 and 500 ng/mL with or without the damage-inducing agent doxorubicin. These cells were then evaluated for cytotoxicity (MTT), cell proliferation and in situ apoptosis induction. To evaluate gene expression, only the cells treated with 500 ng/mL of selenium were used. RNA was extracted from these cells, and the expressions of CASP9, BCL-XL and APC were analyzed by the RT-PCR method. The GAPDH gene was used as a reference gene. The MTT assay showed that selenium was not cytotoxic at any of the concentrations tested. The cell proliferation assay showed that selenium did not interfere with cell proliferation at the three concentrations tested. In contrast, when the three concentrations were combined with doxorubicin, a significant decrease in the proliferation rate was observed. The apoptosis rate was significantly increased in the selenium (500 ng/mL) and doxorubicin group. CASP9 expression was increased and BCL-XL expression decreased in the selenium (500 ng/mL) and doxorubicin group. APC was significantly increased in the selenium group alone. These results show that selenium increases apoptosis, especially when it is associated with a damage-inducing agent. Also, selenium has an important role in the expression of the APC gene, which is related to cell cycle regulation.

  6. Alteration of keratinocyte differentiation and senescence by the tumor promoter dioxin

    International Nuclear Information System (INIS)

    Ray, Soma S.; Swanson, Hollie I.

    2003-01-01

    Exposure to the environmental contaminant dioxin, elicits a variety of responses, which includes tumor promotion, embryotoxicity/teratogenesis, and carcinogenesis in both animals and humans. Many of the effects of dioxin are mediated by the aryl hydrocarbon receptor (AHR), a ligand-activated bHLH (basic helix-loop-helix)/PAS transcription factor. We initiated this study to determine whether dioxin's tumor-promoting activities may lie in its ability to alter proliferation, differentiation, and/or senescence using normal human epidermal keratinocytes (HEKs). Here, we report that dioxin appears to accelerate differentiation as measured by flow cytometry and by increased expression of the differentiation markers involucrin and filaggrin. In addition, dioxin appears to increase proliferation as indicated by an increase in NADH/NADPH production and changes in cell cycle. Finally, dioxin decreases SA (senescence associated) β-galactosidase staining, an indicator of senescence, in the differentiating keratinocytes. These changes were accompanied by decreases in the expression levels of key cell cycle regulatory proteins p53, p16 INK4a , and p14 ARF . Our findings support the idea that dioxin may exert its tumor-promoting actions, in part, by downregulating the expression levels of key tumor suppressor proteins, which may impair the cell's ability to maintain its appropriate cellular status

  7. Deacetylation of H4-K16Ac and heterochromatin assembly in senescence

    Directory of Open Access Journals (Sweden)

    Contrepois Kévin

    2012-08-01

    Full Text Available Abstract Background Cellular senescence is a stress response of mammalian cells leading to a durable arrest of cell proliferation that has been implicated in tumor suppression, wound healing, and aging. The proliferative arrest is mediated by transcriptional repression of genes essential for cell division by the retinoblastoma protein family. This repression is accompanied by varying degrees of heterochromatin assembly, but little is known regarding the molecular mechanisms involved. Results We found that both deacetylation of H4-K16Ac and expression of HMGA1/2 can contribute to DNA compaction during senescence. SIRT2, an NAD-dependent class III histone deacetylase, contributes to H4-K16Ac deacetylation and DNA compaction in human fibroblast cell lines that assemble striking senescence-associated heterochromatin foci (SAHFs. Decreased H4-K16Ac was observed in both replicative and oncogene-induced senescence of these cells. In contrast, this mechanism was inoperative in a fibroblast cell line that did not assemble extensive heterochromatin during senescence. Treatment of senescent cells with trichostatin A, a class I/II histone deacetylase inhibitor, also induced rapid and reversible decondensation of SAHFs. Inhibition of DNA compaction did not significantly affect the stability of the senescent state. Conclusions Variable DNA compaction observed during senescence is explained in part by cell-type specific regulation of H4 deacetylation and HMGA1/2 expression. Deacetylation of H4-K16Ac during senescence may explain reported decreases in this mark during mammalian aging and in cancer cells.

  8. Long non-coding RNA taurine-upregulated gene 1 correlates with poor prognosis, induces cell proliferation, and represses cell apoptosis via targeting aurora kinase A in adult acute myeloid leukemia.

    Science.gov (United States)

    Wang, Xinfeng; Zhang, Lina; Zhao, Fan; Xu, Ruirong; Jiang, Jie; Zhang, Chenglu; Liu, Hong; Huang, Hongming

    2018-04-13

    This study aimed to investigate the correlation of long non-coding RNA (lncRNA) taurine-upregulated gene 1 (TUG1) with clinicopathological feature and prognosis, and to explore its effect on cell proliferation and apoptosis as well as the relevant target genes in adult acute myeloid leukemia (AML). LncRNA TUG1 expression was detected in bone marrow samples from 186 AML patients and 62 controls. Blank mimic, lncRNA TUG1 mimic, blank inhibitor, and lncRNA TUG1 inhibitor lentivirus vectors were transfected in KG-1 cells. Rescue experiment was performed by transfection of lncRNA TUG1 inhibitor and aurora kinase A (AURKA) mimic lentivirus vectors. Cell proliferation, apoptosis, RNA, and protein expressions were determined by CKK-8, annexin V-FITC-propidium iodide, quantitative polymerase chain reaction, and western blot assays. LncRNA TUG1 expression was higher in AML patients compared to controls and correlated with higher white blood cell counts, monosomal karyotype, FLT3-ITD mutation, poor-risk stratification, and poor prognosis, which independently predicted worse event-free survival and overall survival. In vitro, lncRNA TUG1 expression was higher in AML cell lines (KG-1, MOLM-14, HL-60, NB-4, and THP-1 cells) compared to controls. LncRNA TUG1 mimic promoted cell proliferation and decreased cell apoptosis rate, while lncRNA TUG1 inhibitor repressed cell proliferation and increased cell apoptosis rate. Rescue experiment showed that AURKA attenuated the influence of lncRNA TUG1 on AML cell proliferation and apoptosis. In conclusion, lncRNA TUG1 associates with advanced disease and worse prognosis in adult AML patients, and it induces AML cell proliferation and represses cell apoptosis via targeting AURKA.

  9. miR-140-5p regulates hypoxia-mediated human pulmonary artery smooth muscle cell proliferation, apoptosis and differentiation by targeting Dnmt1 and promoting SOD2 expression

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yanwei; Xu, Jing, E-mail: xujingdoc@163.com

    2016-04-22

    miR-140-5p is down-regulated in patients with pulmonary arterial hypertension (PAH) and experimental models of PAH, and inhibits hypoxia-mediated pulmonary artery smooth muscle cell (PASMC) proliferation in vitro. Delivery of synthetic miR-140-5p prevents and treats established, experimental PAH. DNA methyltransferase 1 (Dnmt1) is up-regulated in PAH associated human PASMCs (HPASMCs), which promotes the development of PAH by hypermethylation of CpG islands within the promoter for superoxide dismutase 2 (SOD2) and down-regulating SOD2 expression. We searched for miR-140-5p targets using TargetScan, PicTar and MiRanda tools, and found that Dnmt1 is a potential target of miR-140-5p. Based on these findings, we speculated that miR-140-5p might target Dnmt1 and regulate SOD2 expression to regulate hypoxia-mediated HPASMC proliferation, apoptosis and differentiation. We detected the expression of miR-140-5p, Dnmt1 and SOD2 by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot assays, respectively, and found down-regulation of miR-140-5p and SOD2 and up-regulation of Dnmt1 exist in PAH tissues and hypoxia-mediated HPASMCs. Cell proliferation, apoptosis and differentiation detection showed that miR-140-5p inhibits proliferation and promotes apoptosis and differentiation of HPASMCs in hypoxia, while the effect of Dnmt1 on hypoxia-mediated HPASMCs is reversed. Luciferase assay confirmed that miR-140-5p targets Dnmt1 directly. An inverse correlation is also found between miR-140-5p and Dnmt1 in HPASMCs. In addition, we further investigated whether miR-140-5p and Dnmt1 regulate HPASMC proliferation, apoptosis and differentiation by regulating SOD2 expression, and the results confirmed our speculation. Taken together, these results indicated that miR-140-5p at least partly targets Dnmt1 and regulates SOD2 expression to inhibit proliferation and promote apoptosis and differentiation of HPASMCs in hypoxia. - Highlights: • miR-140-5p and SOD2 are down

  10. Role of nuclear bodies in apoptosis signalling.

    Science.gov (United States)

    Krieghoff-Henning, Eva; Hofmann, Thomas G

    2008-11-01

    Promyelocytic leukemia nuclear bodies (PML NBs) are dynamic macromolecular multiprotein complexes that recruit and release a plethora of proteins. A considerable number of PML NB components play vital roles in apoptosis, senescence regulation and tumour suppression. The molecular basis by which PML NBs control these cellular responses is still just beginning to be understood. In addition to PML itself, numerous further tumour suppressors including transcriptional regulator p53, acetyl transferase CBP (CREB binding protein) and protein kinase HIPK2 (homeodomain interacting protein kinase 2) are recruited to PML NBs in response to genotoxic stress or oncogenic transformation and drive the senescence and apoptosis response by regulating p53 activity. Moreover, in response to death-receptor activation, PML NBs may act as nuclear depots that release apoptotic factors, such as the FLASH (FLICE-associated huge) protein, to amplify the death signal. PML NBs are also associated with other nuclear domains including Cajal bodies and nucleoli and share apoptotic regulators with these domains, implying crosstalk between NBs in apoptosis regulation. In conclusion, PML NBs appear to regulate cell death decisions through different, pathway-specific molecular mechanisms.

  11. MicroRNA-33 promotes the replicative senescence of mouse embryonic fibroblasts by suppressing CDK6

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Shun; Huang, Haijiao; Li, Nanhong; Zhang, Bing; Jia, Yubin; Yang, Yukun; Yuan, Yuan; Xiong, Xing-dong; Wang, Dengchuan; Zheng, Hui-ling [Institute of Aging Research, Guangdong Medical University, Dongguan (China); Guangdong Provincial Key Laboratory of Medical Molecular Diagnostics, Dongguan (China); Institute of Biochemistry & Molecular Biology, Guangdong Medical University, Zhanjiang (China); Liu, Xinguang, E-mail: xgliu64@126.com [Institute of Aging Research, Guangdong Medical University, Dongguan (China); Guangdong Provincial Key Laboratory of Medical Molecular Diagnostics, Dongguan (China); Institute of Biochemistry & Molecular Biology, Guangdong Medical University, Zhanjiang (China)

    2016-05-13

    MicroRNAs are a large class of tiny noncoding RNAs, which have emerged as critical regulators of gene expression, and thus are involved in multiple cellular processes, including cellular senescence. MicroRNA-33 has previously been established to exert crucial effect on cell proliferation, lipid metabolism and cholesterol metabolism. Nonetheless, the association between microRNA-33 and cellular senescence and its underlying molecular mechanism are far to be elucidated. The present study has attempted to probe into the effect of microRNA-33 on MEFs senescence. Our data unveiled that microRNA-33 was dramatically down-regulated in senescent MEFs compared to the young MEFs, and ectopic expression of microRNA-33 promoted MEFs senescence, while knock-down of microRNA-33 exhibited a protective effect against senescence phenotype. Moreover, we verified CDK6 as a direct target of microRNA-33 in mouse. Silencing of CDK6 induced the premature senescence phenotype of MEFs similarly as microRNA-33, while enforced expression of CDK6 significantly reverse the senescence-induction effect of microRNA-33. Taken together, our results suggested that microRNA-33 enhanced the replicative senescence of MEFs potentially by suppressing CDK6 expression. -- Highlights: •MicroRNA-33 was dramatically down-regulated in senescent MEF cells. •Altered expression of microRNA-33 exerted a critical role in MEFs senescence. •MicroRNA-33 promoted the replicative senescence of MEFs via targeting of CDK6.

  12. MicroRNA-33 promotes the replicative senescence of mouse embryonic fibroblasts by suppressing CDK6

    International Nuclear Information System (INIS)

    Xu, Shun; Huang, Haijiao; Li, Nanhong; Zhang, Bing; Jia, Yubin; Yang, Yukun; Yuan, Yuan; Xiong, Xing-dong; Wang, Dengchuan; Zheng, Hui-ling; Liu, Xinguang

    2016-01-01

    MicroRNAs are a large class of tiny noncoding RNAs, which have emerged as critical regulators of gene expression, and thus are involved in multiple cellular processes, including cellular senescence. MicroRNA-33 has previously been established to exert crucial effect on cell proliferation, lipid metabolism and cholesterol metabolism. Nonetheless, the association between microRNA-33 and cellular senescence and its underlying molecular mechanism are far to be elucidated. The present study has attempted to probe into the effect of microRNA-33 on MEFs senescence. Our data unveiled that microRNA-33 was dramatically down-regulated in senescent MEFs compared to the young MEFs, and ectopic expression of microRNA-33 promoted MEFs senescence, while knock-down of microRNA-33 exhibited a protective effect against senescence phenotype. Moreover, we verified CDK6 as a direct target of microRNA-33 in mouse. Silencing of CDK6 induced the premature senescence phenotype of MEFs similarly as microRNA-33, while enforced expression of CDK6 significantly reverse the senescence-induction effect of microRNA-33. Taken together, our results suggested that microRNA-33 enhanced the replicative senescence of MEFs potentially by suppressing CDK6 expression. -- Highlights: •MicroRNA-33 was dramatically down-regulated in senescent MEF cells. •Altered expression of microRNA-33 exerted a critical role in MEFs senescence. •MicroRNA-33 promoted the replicative senescence of MEFs via targeting of CDK6.

  13. The matricellular protein TSP1 promotes human and mouse endothelial cell senescence through CD47 and Nox1.

    Science.gov (United States)

    Meijles, Daniel N; Sahoo, Sanghamitra; Al Ghouleh, Imad; Amaral, Jefferson H; Bienes-Martinez, Raquel; Knupp, Heather E; Attaran, Shireen; Sembrat, John C; Nouraie, Seyed M; Rojas, Mauricio M; Novelli, Enrico M; Gladwin, Mark T; Isenberg, Jeffrey S; Cifuentes-Pagano, Eugenia; Pagano, Patrick J

    2017-10-17

    Senescent cells withdraw from the cell cycle and do not proliferate. The prevalence of senescent compared to normally functioning parenchymal cells increases with age, impairing tissue and organ homeostasis. A contentious principle governing this process has been the redox theory of aging. We linked matricellular protein thrombospondin 1 (TSP1) and its receptor CD47 to the activation of NADPH oxidase 1 (Nox1), but not of the other closely related Nox isoforms, and associated oxidative stress, and to senescence in human cells and aged tissue. In human endothelial cells, TSP1 promoted senescence and attenuated cell cycle progression and proliferation. At the molecular level, TSP1 increased Nox1-dependent generation of reactive oxygen species (ROS), leading to the increased abundance of the transcription factor p53. p53 mediated a DNA damage response that led to senescence through Rb and p21 cip , both of which inhibit cell cycle progression. Nox1 inhibition blocked the ability of TSP1 to increase p53 nuclear localization and p21 cip abundance and its ability to promote senescence. Mice lacking TSP1 showed decreases in ROS production, p21 cip expression, p53 activity, and aging-induced senescence. Conversely, lung tissue from aging humans displayed increases in the abundance of vascular TSP1, Nox1, p53, and p21 cip Finally, genetic ablation or pharmacological blockade of Nox1 in human endothelial cells attenuated TSP1-mediated ROS generation, restored cell cycle progression, and protected against senescence. Together, our results provide insights into the functional interplay between TSP1 and Nox1 in the regulation of endothelial senescence and suggest potential targets for controlling the aging process at the molecular level. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  14. Expression of Caspase-1 in breast cancer tissues and its effects on cell proliferation, apoptosis and invasion.

    Science.gov (United States)

    Sun, Yanxia; Guo, Yingzhen

    2018-05-01

    The present study aimed to detect the expression of Caspase-1 in the tumor tissues and tumor-adjacent tissues of patients with breast cancer, and to investigate the effects of Caspase-1 on the proliferation, apoptosis and invasion of breast cancer cells. Reverse transcription-quantitative polymerase chain reaction was used to detect Caspase-1 mRNA expression in breast cancer tissues and tumor-adjacent tissues from patients. Additionally, the human breast cancer MDA-MB-231 cell line was treated with the Caspase-1 small molecule inhibitor Ac-YVAD-CMK, following which the changes to Caspase-1 protein expression were detected via western blotting. The MTT method detected the changes to cell proliferation, flow cytometry detected the rate of apoptosis, and a Transwell assay was employed to assess invasion. Caspase-1 mRNA expression was significantly decreased in the breast cancer tissues of patients, compared with in the tumor-adjacent tissues, a difference that was statistically significant (P<0.05). Treatment with the Ac-YVAD-CMK markedly decreased the protein expression of Caspase-1 in MDA-MB-231 cells, and the difference was statistically significant (P<0.05). Following this treatment of Ac-YVAD-CMK cells, the proliferation and invasion abilities markedly increased, while the apoptotic levels significantly decreased (P<0.05). In conclusion, the expression of Caspase-1 is low in breast cancer tissues, which may promote the proliferation and invasion of breast cancer cells and could be closely associated with the occurrence and development of breast cancer.

  15. FoxP3 inhibits proliferation and induces apoptosis of gastric cancer cells by activating the apoptotic signaling pathway

    International Nuclear Information System (INIS)

    Ma, Gui-Fen; Chen, Shi-Yao; Sun, Zhi-Rong; Miao, Qing; Liu, Yi-Mei; Zeng, Xiao-Qing; Luo, Tian-Cheng; Ma, Li-Li; Lian, Jing-Jing; Song, Dong-Li

    2013-01-01

    Highlights: ► The article revealed FoxP3 gene function in gastric cancer firstly. ► Present the novel roles of FoxP3 in inhibiting proliferation and promoting apoptosis in gastric cancer cells. ► Overexpression of FoxP3 increased proapoptotic molecules and repressed antiapoptotic molecules. ► Silencing of FoxP3 reduced the expression of proapoptotic genes, such as PARP, caspase-3 and caspase-9. ► FoxP3 is sufficient for activating the apoptotic signaling pathway. -- Abstract: Forkhead Box Protein 3 (FoxP3) was identified as a key transcription factor to the occurring and function of the regulatory T cells (Tregs). However, limited evidence indicated its function in tumor cells. To elucidate the precise roles and underlying molecular mechanism of FoxP3 in gastric cancer (GC), we examined the expression of FoxP3 and the consequences of interfering with FoxP3 gene in human GC cell lines, AGS and MKN45, by multiple cellular and molecular approaches, such as immunofluorescence, gene transfection, CCK-8 assay, clone formation assay, TUNEL assay, Flow cytometry, immunoassay and quantities polymerase chain reaction (PCR). As a result, FoxP3 was expressed both in nucleus and cytoplasm of GC cells. Up-regulation of FoxP3 inhibited cell proliferation and promoted cell apoptosis. Overexpression of FoxP3 increased the protein and mRNA levels of proapoptotic molecules, such as poly ADP-ribose polymerase1 (PARP), caspase-3 and caspase-9, and repressed the expression of antiapoptotic molecules, such as cellular inhibitor of apoptosis-1 (c-IAP1) and the long isoform of B cell leukemia/lymphoma-2 (Bcl-2). Furthermore, silencing of FoxP3 by siRNA in GC cells reduced the expression of proapoptotic genes, such as PARP, caspase-3 and caspase-9. Collectively, our findings identify the novel roles of FoxP3 in inhibiting proliferation and inducing apoptosis in GC cells by regulating apoptotic signaling, which could be a promising therapeutic approach for gastric cancer.

  16. Regulation of cell proliferation and apoptosis in neuroblastoma cells by ccp1, a FGF2 downstream gene

    Directory of Open Access Journals (Sweden)

    Inman Gareth J

    2010-11-01

    Full Text Available Abstract Background Coiled-coil domain containing 115 (Ccdc115 or coiled coil protein-1 (ccp1 was previously identified as a downstream gene of Fibroblast Growth Factor 2 (FGF2 highly expressed in embryonic and adult brain. However, its function has not been characterised to date. Here we hypothesized that ccp1 may be a downstream effecter of FGF2, promoting cell proliferation and protecting from apoptosis. Methods Forced ccp1 expression in mouse embryonic fibroblast (MEF and neuroblastoma SK-N-SH cell line, as well as down-regulation of ccp1 expression by siRNA in NIH3T3, was used to characterize the role of ccp1. Results Ccp1 over-expression increased cell proliferation, whereas down-regulation of ccp1 expression reduced it. Ccp1 was able to increase cell proliferation in the absence of serum. Furthermore, ccp1 reduced apoptosis upon withdrawal of serum in SK-N-SH. The mitogen-activated protein kinase (MAPK or ERK Kinase (MEK inhibitor, U0126, only partially inhibited the ccp1-dependent BrdU incorporation, indicating that other signaling pathway may be involved in ccp1-induced cell proliferation. Induction of Sprouty (SPRY upon FGF2 treatment was accelerated in ccp1 over-expressing cells. Conclusions All together, the results showed that ccp1 regulates cell number by promoting proliferation and suppressing cell death. FGF2 was shown to enhance the effects of ccp1, however, it is likely that other mitogenic factors present in the serum can also enhance the effects. Whether these effects are mediated by FGF2 influencing the ccp1 function or by increasing the ccp1 expression level is still unclear. At least some of the proliferative regulation by ccp1 is mediated by MAPK, however other signaling pathways are likely to be involved.

  17. Hesperidin inhibits HeLa cell proliferation through apoptosis mediated by endoplasmic reticulum stress pathways and cell cycle arrest

    International Nuclear Information System (INIS)

    Wang, Yaoxian; Yu, Hui; Zhang, Jin; Gao, Jing; Ge, Xin; Lou, Ge

    2015-01-01

    Hesperidin (30, 5, 9-dihydroxy-40-methoxy-7-orutinosyl flavanone) is a flavanone that is found mainly in citrus fruits and has been shown to have some anti-neoplastic effects. The aim of the present study was to investigate the effect of hesperidin on apoptosis in human cervical cancer HeLa cells and to identify the mechanism involved. Cells were treated with hesperidin (0, 20, 40, 60, 80, and 100 μM) for 24, 48, or 72 h and relative cell viability was assessed using the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Hesperidin inhibited the proliferation of HeLa cells in a concentration- and time-dependent manner. Hesperidin-induced apoptosis in HeLa cells was characterized by increased nuclear condensation and DNA fragmentation. Furthermore, increased levels of GADD153/CHOP and GRP78 indicated hesperidin-induced apoptosis in HeLa cells involved a caspase-dependent pathway, presumably downstream of the endoplasmic reticulum stress pathway. Both of these proteins are hallmarks of endoplasmic reticulum stress. Hesperidin also promoted the formation of reactive oxygen species, mobilization of intracellular Ca 2+ , loss of mitochondrial membrane potential (ΔΨm), increased release of cytochrome c and apoptosis-inducing factor from mitochondria, and promoted capase-3 activation. It also arrested HeLa cells in the G0/G1 phase in the cell cycle by downregulating the expression of cyclinD1, cyclinE1, and cyclin-dependent kinase 2 at the protein level. The effect of hesperidin was also verified on the human colon cancer cell HT-29 cells. We concluded that hesperidin inhibited HeLa cell proliferation through apoptosis involving endoplasmic reticulum stress pathways and cell cycle arrest

  18. Effect of polysaccharide of dendrobium candidum on proliferation and apoptosis of human corneal epithelial cells in high glucose

    Science.gov (United States)

    Li, Qiangxiang; Chen, Jing; Li, Yajia; Chen, Ting; Zou, Jing; Wang, Hua

    2017-01-01

    Abstract Background: The aim of the study was to observe the effect of polysaccharide of dendrobium candidum (PDC) and high glucose on proliferation, apoptosis of human corneal epithelial cells (HCEC). Methods: The MTT method was used to screen and take the optimal high-glucose concentration, treatment time, and PDC concentration using HCEC and divide it into 4 groups: control group (C), high glucose group (HG), PDC group, and HG + PDC group. We observed and compared the effect of the 4 groups on HCEC proliferation by MTT, apoptosis by Annexin V-FITC/PI double fluorescent staining and flow cytometry (FCM), and expression of bax mRNA and bcl-2 mRNA by RT-qPCR. Results: Compared with the control group, proliferative activity of HCEC cells was reduced; the cells apoptosis ratio was increased; the expression of bax mRNA was increased, and the expression of bcl-2 mRNA was reduced in the HG group. Proliferative activity of HCEC cells in the PDC group was increased, and the expression of bcl-2 mRNA was increased but that of bax mRNA was decreased. Proliferative activity of HCEC cells in the HG + PDC group was increased, but it could not restore to the normal level; the expression of bax mRNA was significantly decreased but the expression of bcl-2 mRNA was significantly increased. Conclusions: Our results demonstrate that high glucose can inhibit proliferative activity and induce apoptosis of HCEC. PDC can improve the proliferative activity of HCEC cells under the high glucose environment and reduce the apoptosis of cells by regulating the expression of bax and bcl-2. PDC play a very important role on protecting and repairing of corneal epithelial cells damage in high glucose. PMID:28796073

  19. Activity of Metabotropic Glutamate Receptor 4 Suppresses Proliferation and Promotes Apoptosis With Inhibition of Gli-1 in Human Glioblastoma Cells

    Directory of Open Access Journals (Sweden)

    Zhichao Zhang

    2018-05-01

    Full Text Available Glioblastoma multiforme (GBM is the most lethal glioma variant in the adult brain and among the deadliest of human cancers. Increasing evidence has shown that metabotropic glutamate receptor subtype 4 (mGluR4 expression may play roles in regulating the growth of neural stem cells as well as several cancer cell lines. Here, we investigated the effects of mGluR4 on the growth and apoptosis of the LN229 GBM cell line. Involvement of Gli-1, one of the key transcription factors in the sonic Hedgehog (SHH signaling pathway, was further explored. In this study, mGluR4 was activated using selective agonist VU0155041; and gene-targeted siRNAs were used to generate loss of function of mGluR4 and Gli-1 in LN229 cells. The results demonstrated that LN229 cells expressed mGluR4 and the agonist VU0155041 decreased cell viability in a dose- and time-dependent manner. Activation of mGluR4 inhibited cyclin D1 expression, activated pro-caspase-8/9/3, and disrupted the balance of Bcl-2/Bax expression, which indicated cell cycle arrest and apoptosis of LN229 cells, respectively. Furthermore, Gli-1 expression was reduced by mGluR4 activation in LN229 cells, and downregulation of Gli-1 expression by gene-targeted siRNA resulted in both inhibition of cell proliferation and promotion of apoptosis. Moreover, VU0155041 treatment substantially blocked SHH-induced cyclin D1 expression and cell proliferation, while increasing TUNEL-positive cells and the activation of apoptosis-related proteins. We concluded that activation of mGluR4 expressed in LN229 cells could inhibit GBM cell growth by decreasing cell proliferation and promoting apoptosis. Further suppression of intracellular Gli-1 expression might be involved in the action of mGluR4 on cancer cells. Our study suggested a novel role of mGluR4, which might serve as a potential drug target for control of GBM cell growth.

  20. In Vitro Proliferation and Anti-Apoptosis of the Papain-Generated Casein and Soy Protein Hydrolysates towards Osteoblastic Cells (hFOB1.19).

    Science.gov (United States)

    Pan, Xiao-Wen; Zhao, Xin-Huai

    2015-06-17

    Casein and soy protein were digested by papain to three degrees of hydrolysis (DH) 7.3%-13.3%, to obtain respective six casein and soy protein hydrolysates, aiming to clarify their in vitro proliferation and anti-apoptosis towards a human osteoblastic cell line (hFOB1.19 cells). Six casein and soy protein hydrolysates at five levels (0.01-0.2 mg/mL) mostly showed proliferation as positive 17β-estradiol did, because they conferred the osteoblasts with cell viability of 100%-114% and 104%-123%, respectively. The hydrolysates of higher DH values had stronger proliferation. Casein and soy protein hydrolysates of the highest DH values altered cell cycle progression, and enhanced cell proportion of S-phase from 50.5% to 56.5% and 60.5%. The two also antagonized etoposide- and NaF-induced osteoblast apoptosis. In apoptotic prevention, apoptotic cells were decreased from 31.6% to 22.6% and 15.6% (etoposide treatment), or from 19.5% to 17.7% and 12.4% (NaF treatment), respectively. In apoptotic reversal, soy protein hydrolysate decreased apoptotic cells from 13.3% to 11.7% (etoposide treatment), or from 14.5% to 11.0% (NaF treatment), but casein hydrolysate showed no reversal effect. It is concluded that the hydrolysates of two kinds had estradiol-like action on the osteoblasts, and soy protein hydrolysates had stronger proliferation and anti-apoptosis on the osteoblasts than casein hydrolysates.

  1. Xingshentongqiao Decoction Mediates Proliferation, Apoptosis, Orexin-A Receptor and Orexin-B Receptor Messenger Ribonucleic Acid Expression and Represses Mitogen-activated Protein Kinase Signaling

    Directory of Open Access Journals (Sweden)

    Yuanli Dong

    2015-01-01

    Full Text Available Background: Hypocretin (HCRT signaling plays an important role in the pathogenesis of narcolepsy and can be significantly influenced by Chinese herbal therapy. Our previous study showed that xingshentongqiao decoction (XSTQ is clinically effective for the treatment of narcolepsy. To determine whether XSTQ improves narcolepsy by modulating HCRT signaling, we investigated its effects on SH-SY5Y cell proliferation, apoptosis, and HCRT receptor 1/2 (orexin receptor 1 [OX1R] and orexin receptor 2 [OX2R] expression. The signaling pathways involved in these processes were also assessed. Methods: The effects of XSTQ on proliferation and apoptosis in SH-SY5Y cells were assessed using cell counting kit-8 and annexin V-fluorescein isothiocyanate assays. OX1R and OX2R expression was assessed by quantitative real-time polymerase chain reaction analysis. Western blotting for mitogen-activated protein kinase (MAPK pathway activation was performed to further assess the signaling mechanism of XSTQ. Results: XSTQ reduced the proliferation and induced apoptosis of SH-SY5Y cells. This effect was accompanied by the upregulation of OX1R and OX2R expression and the reduced phosphorylation of extracellular signal-regulated kinase (Erk 1/2, p38 MAPK and c-Jun N-terminal kinase (JNK. Conclusions: XSTQ inhibits proliferation and induces apoptosis in SH-SY5Y cells. XSTQ also promotes OX1R and OX2R expression. These effects are associated with the repression of the Erk1/2, p38 MAPK, and JNK signaling pathways. These results define a molecular mechanism for XSTQ in regulating HCRT and MAPK activation, which may explain its ability to treat narcolepsy.

  2. Kefir induces apoptosis and inhibits cell proliferation in human acute erythroleukemia.

    Science.gov (United States)

    Jalali, Fatemeh; Sharifi, Mohammadreza; Salehi, Rasoul

    2016-01-01

    Acute erythroleukemia is an uncommon subtype of acute myeloid leukemia which has been considered to be a subtype of AML with a worse prognosis. Intensive chemotherapy is the first line of treatment. In recent years, the effect of kefir on some malignancies has been experimented. Kefir is a kind of beverage, which obtained by incubation of kefir grains with raw milk. Kefir grains are a symbiotic complex of different kinds of yeasts and bacteria, especially lactic acid bacteria which gather in a mostly carbohydrate matrix, named kefiran. We investigated the effect of kefir on acute erythroleukemia cell line (KG-1) and peripheral blood mononuclear cells (PBMCs). The cell line and PBMCs were treated with different doses of kefir and milk and incubated for three different times. We used Polymixin B to block the lipopolysaccharide and NaOH (1 mol/l) to neutralize the acidic media. Viability was detected by MTT assay. Apoptosis and necrosis were assessed by annexin-propidium iodide staining. Our results showed that kefir induced apoptosis and necrosis in KG-1 cell line. It was revealed that kefir decreased proliferation in erythroleukemia cell line. We did not observe a remarkable effect of kefir on PBMCs. Our study suggested that kefir may have potential to be an effective treatment for erythroleukemia.

  3. The "multiple hormone deficiency" theory of aging: is human senescence caused mainly by multiple hormone deficiencies?

    Science.gov (United States)

    Hertoghe, T

    2005-12-01

    In the human body, the productions, levels and cell receptors of most hormones progressively decline with age, gradually putting the body into various states of endocrine deficiency. The circadian cycles of these hormones also change, sometimes profoundly, with time. In aging individuals, the well-balanced endocrine system can fall into a chaotic condition with losses, phase-advancements, phase delays, unpredictable irregularities of nycthemeral hormone cycles, in particular in very old or sick individuals. The desynchronization makes hormone activities peak at the wrong times and become inefficient, and in certain cases health threatening. The occurrence of multiple hormone deficits and spilling through desynchronization may constitute the major causes of human senescence, and they are treatable causes. Several arguments can be put forward to support the view that senescence is mainly a multiple hormone deficiency syndrome: First, many if not most of the signs, symptoms and diseases (including cardiovascular diseases, cancer, obesity, diabetes, osteoporosis, dementia) of senescence are similar to physical consequences of hormone deficiencies and may be caused by hormone deficiencies. Second, most of the presumed causes of senescence such as excessive free radical formation, glycation, cross-linking of proteins, imbalanced apoptosis system, accumulation of waste products, failure of repair systems, deficient immune system, may be caused or favored by hormone deficiencies. Even genetic causes such as limits to cell proliferation (such as the Hayflick limit of cell division), poor gene polymorphisms, premature telomere shortening and activation of possible genetic "dead programs" may have links with hormone deficiencies, being either the consequence, the cause, or the major favoring factor of hormone deficiencies. Third, well-dosed and -balanced hormone supplements may slow down or stop the progression of signs, symptoms, or diseases of senescence and may often

  4. Downregulation of the long non-coding RNA taurine-upregulated gene 1 inhibits glioma cell proliferation and invasion and promotes apoptosis.

    Science.gov (United States)

    Zhao, Zhijun; Wang, Bin; Hao, Junhai; Man, Weitao; Chang, Yongkai; Ma, Shunchang; Hu, Yeshuai; Liu, Fusheng; Yang, Jun

    2018-03-01

    Expression of the long non-coding RNA taurine-upregulated gene 1 (TUG1) is associated with various aggressive tumors. The present study aimed to investigate the biological function of TUG1 in regulating apoptosis, proliferation, invasion and cell cycle distribution in human glioma U251 cells. Lentivirus-mediated TUG1-specific microRNA was transfected into U251 cells to abrogate the expression of TUG1. Flow cytometry analysis was used to examine the cell cycle distribution and apoptosis of U251 cells. Cellular proliferation was examined using Cell Counting Kit-8 (CCK-8) assays and invasion was examined by Transwell assays. The apoptotic rate of cells in the TUG1-knockdown group was significantly higher than in the negative control (NC) group (11.58 vs. 9.14%, PTUG1-knockdown group was lower compared with that of the NC group. A Transwell invasion assay was performed, which revealed that the number of invaded cells from the TUG1-knockdown group was the less compared with that of the NC group. In addition, the G 0 /G 1 phase population was significantly increased within the treated group (44.85 vs. 38.45%, PTUG1 may inhibit proliferation and invasion, and promote glioma U251 cell apoptosis. In addition, knockdown of TUG1 may have an effect on cell cycle arrest. The data presented in the current study indicated that TUG1 may be a novel therapeutic target for glioma.

  5. miR-125b induces cellular senescence in malignant melanoma

    DEFF Research Database (Denmark)

    Nyholm, Anne Marie; Lerche, Catharina M; Manfé, Valentina

    2014-01-01

    transfected melanoma cell line Mel-Juso and then investigated the effect of the presence of a stable overexpression of miR-125b on growth by western blotting, flow cytometry and β-galactosidase staining. The tumourogenicity of the transfected cells was tested using a murine model and the tumours were further...... examined with in-situ-hybridization. RESULTS: In primary human tumours and in lymph node metastases increased expression of miR-125b was found in single, large tumour cells with abundant cytoplasm. A stable overexpression of miR-125b in human melanoma cell line Mel-Juso resulted in a G0/G1 cell cycle block...... and emergence of large cells expressing senescence markers: senescence-associated beta-galactosidase, p21, p27 and p53. Mel-Juso cells overexpressing miR-125b were tumourigenic in mice, but the tumours exhibited higher level of cell senescence and decreased expression of proliferation markers, cyclin D1 and Ki...

  6. The different expression profiles of microRNAs in elderly and young human dental pulp and the role of miR-433 in human dental pulp cells.

    Science.gov (United States)

    Wang, Kejing; Li, Li; Wu, Junjun; Qiu, Qin; Zhou, Fengjuan; Wu, Hongkun

    2015-03-01

    As a kind of endogenous noncoding small RNA, MicroRNA (miRNA) plays important roles of regulation to various physiological functions, while its affections on senescence of human dental pulp cell (HDPCs) are still unknown. Thus, we identified the senescence-associated miRNAs in HDPCs by microarray analysis, predicted their targets and regulatory signaling pathway by gene ontology and Kyoto encyclopedia of genes and genomes pathway database analysis. After validated, the senescence-associated miRNAs' expression level was up- and down-regulated using lentivirus package and cell transfection to find its role in HDPCs' morphology, proliferation, apoptosis, and mineralization. The results showed 27 miRNAs differentially expressed at least 1.5-fold, of which 16 were up-regulated and 11 down-regulated, the function of their targets was mainly focused on signal transduction, cell proliferation, apoptosis, and transcription regulation. According to the change fold, we speculated that miR-433 could be one of the vital senescence-associated miRNAs of HDPCs and found its target (GRB2), validated that miR-433 could negatively regulate GRB2 and the RAS-MAPK signaling pathway, leading to the decline of proliferation and mineralization ability of HDPCs and the acceleration of cell apoptosis, suggesting the regulation of miR-433 might be the potential target to promote repair and regeneration of HDPCs in the elderly. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  7. Dual mTORC1/C2 inhibitors suppress cellular geroconversion (a senescence program).

    Science.gov (United States)

    Leontieva, Olga V; Demidenko, Zoya N; Blagosklonny, Mikhail V

    2015-09-15

    In proliferating cells, mTOR is active and promotes cell growth. When the cell cycle is arrested, then mTOR converts reversible arrest to senescence (geroconversion). Rapamycin and other rapalogs suppress geroconversion, maintaining quiescence instead. Here we showed that ATP-competitive kinase inhibitors (Torin1 and PP242), which inhibit both mTORC1 and TORC2, also suppressed geroconversion. Despite inhibition of proliferation (in proliferating cells), mTOR inhibitors preserved re-proliferative potential (RP) in arrested cells. In p21-arrested cells, Torin 1 and PP242 detectably suppressed geroconversion at concentrations as low as 1-3 nM and 10-30 nM, reaching maximal gerosuppression at 30 nM and 300 nM, respectively. Near-maximal gerosuppression coincided with inhibition of p-S6K(T389) and p-S6(S235/236). Dual mTOR inhibitors prevented senescent morphology and hypertrophy. Our study warrants investigation into whether low doses of dual mTOR inhibitors will prolong animal life span and delay age-related diseases. A new class of potential anti-aging drugs can be envisioned.

  8. 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...

  9. Preventive Effects of Epigallocatechin-3-O-Gallate against Replicative Senescence Associated with p53 Acetylation in Human Dermal Fibroblasts

    Directory of Open Access Journals (Sweden)

    Dong-Wook Han

    2012-01-01

    Full Text Available Considering the various pharmacological activities of epigallocatechin-3-O-gallate (EGCG including anticancer, and anti-inflammatory, antidiabetic, and so forth, relatively less attention has been paid to the antiaging effect of EGCG on primary cells. In this study, the preventive effects of EGCG against serial passage-induced senescence were investigated in primary cells including rat vascular smooth muscle cells (RVSMCs, human dermal fibroblasts (HDFs, and human articular chondrocytes (HACs. The involvement of Sirt1 and acetylated p53 was examined as an underlying mechanism for the senescence preventive activity of EGCG in HDFs. All cells were employed with the initial passage number (PN between 3 and 7. For inducing senescence, the cells were serially passaged at the predetermined times and intervals in the absence or presence of EGCG (50 or 100 μM. Serial passage-induced senescence in RVSMCs and HACs was able to be significantly prevented at 50 μM EGCG, while in HDFs, 100 μM EGCG could significantly prevent senescence and recover their cell cycle progression close to the normal level. Furthermore, EGCG was found to prevent serial passage- and H2O2-induced senescence in HDFs by suppressing p53 acetylation, but the Sirt1 activity was unaffected. In addition, proliferating HDFs showed similar cellular uptake of FITC-conjugated EGCG into the cytoplasm with their senescent counterparts but different nuclear translocation of it from them, which would partly account for the differential responses to EGCG in proliferating versus senescent cells. Taking these results into consideration, it is suggested that EGCG may be exploited to craft strategies for the development of an antiaging or age-delaying agent.

  10. Effects of PARP-1 inhibitors AG-014699 and AZD2281 on proliferation and apoptosis of human hepatoma cell line HepG2

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    DU Senrong

    2015-06-01

    Full Text Available ObjectiveTo observe the inhibitory and pro-apoptotic effects of two poly(ADP-ribose polymerase (PARP-1 inhibitors, AG-014699 and AZD2281, on human hepatoma HepG2 cells and preliminarily explore the mechanism by which AG-014699 induces HepG2 cell apoptosis, and to provide a new therapeutic target for hepatoma. MethodsThe effects of different concentrations of AG-014699 and AZD2281 on HepG2 cell proliferation were determined by MTT assay. The cell apoptosis rate was measured by flow cytometry. The expression levels of caspase-3 and caspase-8 were measured by Western Blot. Inter-group comparison was made by t test. ResultsBoth AG-014699 and AZD2281 suppressed HepG2 cell proliferation in a time- and dose-dependent manner. However, the sensitivity of HepG2 cells to the two PARP-1 inhibitors was different. The half-maximal inhibitory concentrations of AG-014699 and AZD2281 at 48 h determined by MTT assay were about 20 μmol/L and 400 μmol/L, respectively. Flow cytometry and Western blot were not used to evaluate the apoptosis of HepG2 cells exposed to AZD2281 to which these cells were not sensitive. HepG2 cell apoptosis could be induced by 10, 30, and 50 μmol/L AG-014699, and the highest apoptosis rate at 48 h was significantly higher than that of the control group (3100%±2.13% vs 09%±0013%, P<0.01. Compared with those in the control group, the protein levels of caspase-3 and caspase-8 in HepG2 cells after 48-h exposure to 30, and 50 μmol/L AG-014699 increased. ConclusionThe two PARP-1 inhibitors AG-014699 and AZD2281 can inhibit the proliferation of HepG2 cells, which showed different sensitivities to the two inhibitors. AG-014699 can induce HepG2 cell apoptosis by up-regulating the protein expression of caspase-3 and caspase-8.

  11. MicroRNA-101 inhibits cell proliferation, promotes cell apoptosis and increases sensitivity of breast cancer MDA-MB-231 cells to paclitaxel

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    Qiu-Lin Ke

    2016-02-01

    Full Text Available Objective: To explore the effect that miR-101 inhibits breast cancer MDA-MB-231 cell proliferation and increases the chemosensitivity of paclitaxel to breast cancer MDA-MB-231 cells and its influence on protein expression level of target gene Bcl2. Methods: miR-101 was artificially synthesized, it used liposome 3000 to transfect MDA-MB-231 cells, and experiment was divided into three groups: blank control group, negative control group and miR-101 group. MTT assay was used to detect the effect of miR-101 on MDA-MB-231 cell proliferation and chemosensitivity of paclitaxel-mediated MDA-MB-231 cells; flow cytometer was used to detect cell apoptosis. Real-time PCR and Western bloting were used to detect the changes of mRNA and protein expression levels of Bcl2. Results: After miR-101 transfected MDA-MB- 231 cells, cell proliferation ability significantly decreased compared with negative control group, and differences had statistical significance (P<0.01; after paclitaxel was used to process cells, IC50 of miR-101-processing group decreased by 2.45 times compared with blank control group, differences had statistical significance (P<0.05 and differences between blank control group and negative control group had no statistical significance; detection results by flow cytometer showed that both early-stage and late-stage apoptosis rates of MDA-MB-231 cells of miR-101 group were significantly higher than those of negative control group (P<0.05, and early-stage apoptosis rate was more significant (P<0.01; after transfection of miR-101, mRNA and protein levels of Bcl2 of MDA-MB-231 cells significantly decreased, and differences had statistical significance (P<0.05. Conclusion: miR-101 can inhibit breast cancer MDAMB- 231 cell proliferation through targeting and downregulating Bcl2, thereby increasing the chemosensitivity of breast cancer cells to paclitaxel and promoting cell apoptosis.

  12. MicroRNA-98 rescues proliferation and alleviates ox-LDL-induced apoptosis in HUVECs by targeting LOX-1

    Science.gov (United States)

    Chen, Zhibo; Wang, Mian; He, Qiong; Li, Zilun; Zhao, Yang; Wang, Wenjian; Ma, Jieyi; Li, Yongxin; Chang, Guangqi

    2017-01-01

    Oxidized low-density lipoprotein (ox-LDL) is a major and critical mediator of atherosclerosis, and the underlying mechanism is thought to involve the ox-LDL-induced dysfunction of endothelial cells (ECs). MicroRNAs (miRNAs), which are a group of small non-coding RNA molecules that post-transcriptionally regulate the expression of target genes, have been associated with diverse cellular functions and the pathogenesis of various diseases, including atherosclerosis. miRNA-98 (miR-98) has been demonstrated to be involved in the regulation of cellular apoptosis; however, the role of miR-98 in ox-LDL-induced dysfunction of ECs and atherosclerosis has yet to be elucidated. Therefore, the present study aimed to investigate the role of miR-98 in ox-LDL-induced dysfunction of ECs and the underlying mechanism. It was demonstrated that miR-98 expression was markedly downregulated in ox-LDL-treated human umbilical vein ECs (HUVECs) and that miR-98 promoted the proliferation and alleviated apoptosis of HUVECs exposed to ox-LDL. In addition, the results demonstrated that lectin-like oxidized low-density lipoprotein receptor 1 (LOX-1) was a direct target of miR-98 in HUVECs, as indicated by a luciferase assay. The results of the present study suggested that miR-98 may inhibit the uptake of toxic ox-LDL, maintain HUVEC proliferation and protect HUVECs against apoptosis via the suppression of LOX-1. PMID:28565756

  13. Red Light Combined with Blue Light Irradiation Regulates Proliferation and Apoptosis in Skin Keratinocytes in Combination with Low Concentrations of Curcumin.

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    Tianhui Niu

    Full Text Available Curcumin is a widely known natural phytochemical from plant Curcuma longa. In recent years, curcumin has received increasing attention because of its capability to induce apoptosis and inhibit cell proliferation as well as its anti-inflammatory properties in different cancer cells. However, the therapeutic benefits of curcumin are severely hampered due to its particularly low absorption via trans-dermal or oral bioavailability. Phototherapy with visible light is gaining more and more support in dermatological therapy. Red light is part of the visible light spectrum, which is able to deeply penetrate the skin to about 6 mm, and directly affect the fibroblast of the skin dermis. Blue light is UV-free irradiation which is fit for treating chronic inflammation diseases. In this study, we show that curcumin at low concentrations (1.25-3.12 μM has a strong anti-proliferative effect on TNF-α-induced psoriasis-like inflammation when applied in combination with light-emitting-diode devices. The treatment was especially effective when LED blue light at 405 nm was combined with red light at 630 or 660 nm, which markedly amplified the anti-proliferative and apoptosis-inducing effects of curcumin. The experimental results demonstrated that this treatment reduced the viability of human skin keratinocytes, decreased cell proliferation, induced apoptosis, inhibited NF-κB activity and activated caspase-8 and caspase-9 while preserving the cell membrane integrity. Moreover, the combined treatment also down-regulated the phosphorylation level of Akt and ERK. Taken together, our results indicated that the combination of curcumin with LED blue light united red light irradiation can attain a higher efficiency of regulating proliferation and apoptosis in skin keratinocytes.

  14. Red Light Combined with Blue Light Irradiation Regulates Proliferation and Apoptosis in Skin Keratinocytes in Combination with Low Concentrations of Curcumin

    Science.gov (United States)

    Cai, Qing; Ren, Qu; Wei, Lizhao

    2015-01-01

    Curcumin is a widely known natural phytochemical from plant Curcuma longa. In recent years, curcumin has received increasing attention because of its capability to induce apoptosis and inhibit cell proliferation as well as its anti-inflammatory properties in different cancer cells. However, the therapeutic benefits of curcumin are severely hampered due to its particularly low absorption via trans-dermal or oral bioavailability. Phototherapy with visible light is gaining more and more support in dermatological therapy. Red light is part of the visible light spectrum, which is able to deeply penetrate the skin to about 6 mm, and directly affect the fibroblast of the skin dermis. Blue light is UV-free irradiation which is fit for treating chronic inflammation diseases. In this study, we show that curcumin at low concentrations (1.25–3.12 μM) has a strong anti-proliferative effect on TNF-α-induced psoriasis-like inflammation when applied in combination with light-emitting-diode devices. The treatment was especially effective when LED blue light at 405 nm was combined with red light at 630 or 660 nm, which markedly amplified the anti-proliferative and apoptosis-inducing effects of curcumin. The experimental results demonstrated that this treatment reduced the viability of human skin keratinocytes, decreased cell proliferation, induced apoptosis, inhibited NF-κB activity and activated caspase-8 and caspase-9 while preserving the cell membrane integrity. Moreover, the combined treatment also down-regulated the phosphorylation level of Akt and ERK. Taken together, our results indicated that the combination of curcumin with LED blue light united red light irradiation can attain a higher efficiency of regulating proliferation and apoptosis in skin keratinocytes. PMID:26382065

  15. Resveratrol prevents oxidative stress-induced senescence and proliferative dysfunction by activating the AMPK-FOXO3 cascade in cultured primary human keratinocytes.

    Directory of Open Access Journals (Sweden)

    Yasuo Ido

    Full Text Available The aging process is perceived as resulting from a combination of intrinsic factors such as changes in intracellular signaling and extrinsic factors, most notably environmental stressors. In skin, the relationship between intrinsic changes and keratinocyte function is not clearly understood. Previously, we found that increasing the activity of AMP-activated protein kinase (AMPK suppressed senescence in hydrogen peroxide (H2O2-treated human primary keratinocytes, a model of oxidative stress-induced cellular aging. Using this model in the present study, we observed that resveratrol, an agent that increases the activities of both AMPK and sirtuins, ameliorated two age-associated phenotypes: cellular senescence and proliferative dysfunction. In addition, we found that treatment of keratinocytes with Ex527, a specific inhibitor of sirtuin 1 (SIRT1, attenuated the ability of resveratrol to suppress senescence. In keeping with the latter observation, we noted that compared to non-senescent keratinocytes, senescent cells lacked SIRT1. In addition to these effects on H2O2-induced senescence, resveratrol also prevented the H2O2-induced decrease in proliferation (as indicated by 3H-thymidine incorporation in the presence of insulin. This effect was abrogated by inhibition of AMPK but not SIRT1. Compared to endothelium, we found that human keratinocytes expressed relatively high levels of Forkhead box O3 (FOXO3, a downstream target of both AMPK and SIRT1. Treatment of keratinocytes with resveratrol transactivated FOXO3 and increased the expression of its target genes including catalase. Resveratrol's effects on both senescence and proliferation disappeared when FOXO3 was knocked down. Finally, we performed an exploratory study which showed that skin from humans over 50 years old had lower AMPK activity than skin from individuals under age 20. Collectively, these findings suggest that the effects of resveratrol on keratinocyte senescence and proliferation

  16. Hot water-extracted Lycium barbarum and Rehmannia glutinosa inhibit proliferation and induce apoptosis of hepatocellular carcinoma cells

    Science.gov (United States)

    Chao, Jane C-J; Chiang, Shih-Wen; Wang, Ching-Chiung; Tsai, Ya-Hui; Wu, Ming-Shun

    2006-01-01

    AIM: To investigate the effect of hot water-extracted Lycium barbarum (LBE) and Rehmannia glutinosa (RGE) on cell proliferation and apoptosis in rat and/or human hepatocellular carcinoma (HCC) cells. METHODS: Rat (H-4-II-E) and human HCC (HA22T/VGH) cell lines were incubated with various concentrations (0-10 g/L) of hot water-extracted LBE and RGE. After 6-24 h incubation, cell proliferation (n = 6) was measured by a colorimetric method. The apoptotic cells (n = 6) were detected by flow cytometry. The expression of p53 protein (n = 3) was determined by SDS-PAGE and Western blotting. RESULTS: Crude LBE (2-5 g/L) and RGE (2-10 g/L) dose-dependently inhibited proliferation of H-4-II-E cells by 11% (P < 0.05) to 85% (P < 0.01) after 6-24 h treatment. Crude LBE at a dose of 5 g/L suppressed cell proliferation of H-4-II-E cells more effectively than crude RGE after 6-24 h incubation (P < 0.01). Crude LBE (2-10 g/L) and RGE (2-5 g/L) also dose-dependently inhibited proliferation of HA22T/VGH cells by 14%-43% (P < 0.01) after 24 h. Crude LBE at a dose of 10 g/L inhibited the proliferation of HA22T/VGH cells more effectively than crude RGE (56.8% ± 1.6% vs 70.3% ± 3.1% of control, P = 0.0003 < 0.01). The apoptotic cells significantly increased in H-4-II-E cells after 24 h treatment with higher doses of crude LBE (2-5 g/L) and RGE (5-10 g/L) (P < 0.01). The expression of p53 protein in H-4-II-E cells was 119% and 143% of the control group compared with the LBE-treated (2, 5 g/L) groups, and 110% and 132% of the control group compared with the RGE -treated (5, 10 g/L) groups after 24 h. CONCLUSION: Hot water-extracted crude LBE (2-5 g/L) and RGE (5-10 g/L) inhibit proliferation and stimulate p53-mediated apoptosis in HCC cells. PMID:16874858

  17. Senescence Meets Dedifferentiation

    Science.gov (United States)

    Givaty Rapp, Yemima; Ransbotyn, Vanessa; Grafi, Gideon

    2015-01-01

    Senescence represents the final stage of leaf development but is often induced prematurely following exposure to biotic and abiotic stresses. Leaf senescence is manifested by color change from green to yellow (due to chlorophyll degradation) or to red (due to de novo synthesis of anthocyanins coupled with chlorophyll degradation) and frequently culminates in programmed death of leaves. However, the breakdown of chlorophyll and macromolecules such as proteins and RNAs that occurs during leaf senescence does not necessarily represent a one-way road to death but rather a reversible process whereby senescing leaves can, under certain conditions, re-green and regain their photosynthetic capacity. This phenomenon essentially distinguishes senescence from programmed cell death, leading researchers to hypothesize that changes occurring during senescence might represent a process of trans-differentiation, that is the conversion of one cell type to another. In this review, we highlight attributes common to senescence and dedifferentiation including chromatin structure and activation of transposable elements and provide further support to the notion that senescence is not merely a deterioration process leading to death but rather a unique developmental state resembling dedifferentiation. PMID:27135333

  18. Azathioprine desensitizes liver cancer cells to insulin-like growth factor 1 and causes apoptosis when it is combined with bafilomycin A1

    International Nuclear Information System (INIS)

    Hernández-Breijo, Borja; Monserrat, Jorge; Román, Irene D.; González-Rodríguez, Águeda; Fernández-Moreno, M. Dolores

    2013-01-01

    Hepatoblastoma is a primary liver cancer that affects children, due to the sensitivity of this tumor to insulin-like growth factor 1 (IGF-1). In this paper we show that azathioprine (AZA) is capable of inhibiting IGF1-mediated signaling cascade in HepG2 cells. The efficiency of AZA on inhibition of proliferation differs in the evaluated cell lines as follows: HepG2 (an experimental model of hepatoblastoma) > Hep3B (derived from a hepatocellular carcinoma) > HuH6 (derived from a hepatoblastoma) ≫ HuH7 (derived from a hepatocellular carcinoma) = Chang Liver cells (a non-malignant cellular model). The effect of AZA in HepG2 cells has been proven to derive from activation of Ras/ERK/TSC2, leading to activation of mTOR/p70S6K in a sustained manner. p70S6K phosphorylates IRS-1 in serine 307 which leads to the uncoupling between IRS-1 and p85 (the regulatory subunit of PI3K) and therefore causing the lack of response of HepG2 to IGF-1. As a consequence, proliferation induced by IGF-1 is inhibited by AZA and autophagy increases leading to senescence of HepG2 cells. Our results suggest that AZA induces the autophagic process in HepG2 activating senescence, and driving to deceleration of cell cycle but not to apoptosis. However, when simultaneous to AZA treatment the autophagy was inhibited by bafilomycin A1 and the degradation of regulatory proteins of cell cycle (e.g. Rb, E2F, and cyclin D1) provoked apoptosis. In conclusion, AZA induces resistance in hepatoblastoma cells to IGF-1, which leads to autophagy activation, and causes apoptosis when it is combined with bafilomycin A1. We are presenting here a novel mechanism of action of azathioprine, which could be useful in treatment of IGF-1 dependent tumors, especially in its combination with other drugs. - Highlights: • Azathioprine activated Ras/ERK/TSC-2/mTOR/p70S6K signaling pathway in HepG2 cells. • Azathioprine inhibited IGF-1-mediated signaling cascade. • Azathioprine induced autophagy leading to cell cycle

  19. Azathioprine desensitizes liver cancer cells to insulin-like growth factor 1 and causes apoptosis when it is combined with bafilomycin A1

    Energy Technology Data Exchange (ETDEWEB)

    Hernández-Breijo, Borja [Departamento de Biología de Sistemas, Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD), Universidad de Alcalá, 28871 Alcalá de Henares (Spain); Monserrat, Jorge [Departamento de Medicina y Especialidades Médicas, Universidad de Alcalá, 28871 Alcalá de Henares (Spain); Román, Irene D. [Departamento de Biología de Sistemas, Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD), Universidad de Alcalá, 28871 Alcalá de Henares (Spain); González-Rodríguez, Águeda [Departamento de Biomedicina y Biotecnología, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Universidad de Alcalá, 28871 Alcalá de Henares (Spain); Fernández-Moreno, M. Dolores [Departamento de Biología de Sistemas, Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD), Universidad de Alcalá, 28871 Alcalá de Henares (Spain); and others

    2013-11-01

    Hepatoblastoma is a primary liver cancer that affects children, due to the sensitivity of this tumor to insulin-like growth factor 1 (IGF-1). In this paper we show that azathioprine (AZA) is capable of inhibiting IGF1-mediated signaling cascade in HepG2 cells. The efficiency of AZA on inhibition of proliferation differs in the evaluated cell lines as follows: HepG2 (an experimental model of hepatoblastoma) > Hep3B (derived from a hepatocellular carcinoma) > HuH6 (derived from a hepatoblastoma) ≫ HuH7 (derived from a hepatocellular carcinoma) = Chang Liver cells (a non-malignant cellular model). The effect of AZA in HepG2 cells has been proven to derive from activation of Ras/ERK/TSC2, leading to activation of mTOR/p70S6K in a sustained manner. p70S6K phosphorylates IRS-1 in serine 307 which leads to the uncoupling between IRS-1 and p85 (the regulatory subunit of PI3K) and therefore causing the lack of response of HepG2 to IGF-1. As a consequence, proliferation induced by IGF-1 is inhibited by AZA and autophagy increases leading to senescence of HepG2 cells. Our results suggest that AZA induces the autophagic process in HepG2 activating senescence, and driving to deceleration of cell cycle but not to apoptosis. However, when simultaneous to AZA treatment the autophagy was inhibited by bafilomycin A1 and the degradation of regulatory proteins of cell cycle (e.g. Rb, E2F, and cyclin D1) provoked apoptosis. In conclusion, AZA induces resistance in hepatoblastoma cells to IGF-1, which leads to autophagy activation, and causes apoptosis when it is combined with bafilomycin A1. We are presenting here a novel mechanism of action of azathioprine, which could be useful in treatment of IGF-1 dependent tumors, especially in its combination with other drugs. - Highlights: • Azathioprine activated Ras/ERK/TSC-2/mTOR/p70S6K signaling pathway in HepG2 cells. • Azathioprine inhibited IGF-1-mediated signaling cascade. • Azathioprine induced autophagy leading to cell cycle

  20. Effects of hydroxyapatite nanoparticles on proliferation and apoptosis of human breast cancer cells (MCF-7)

    International Nuclear Information System (INIS)

    Meena, Ramovatar; Kesari, Kavindra Kumar; Rani, Madhu; Paulraj, R.

    2012-01-01

    The study aimed to correlate cell proliferation inhibition with oxidative stress and p53 protein expression in cancerous cells. Hydroxyapatite (HAP) (Ca 10 (PO 4 ) 6 (OH) 2 ) is the essential component of inorganic composition in human bone. It has been found to have obvious inhibitory function on growth of many kinds of tumor cells and its nanoparticle has stronger anti-cancerous effect than macromolecule microparticles. Human breast cancer cells (MCF-7) were cultured and treated with HAP nanoparticles at various concentrations. Cells viability was detected with MTT colorimetric assay. The morphology of the cancerous cells was performed by transmission electron microscopy and the expression of a cell apoptosis related gene (p53) was determined by ELISA assay and flow cytometry (FCM). The intracellular reactive oxygen species (ROS) level in HAP exposed cells was measured by H 2 DCFDA staining. DNA damage was measured by single-cell gel electrophoresis assay. The statistical analysis was done by one way ANOVA. The cellular proliferation inhibition rate was significantly (p < 0.05) increasing in a dose-dependent manner of HAP nanoparticles. Cell apoptotic characters were observed after MCF-7 cells were treated by HAP nanoparticles for 48 h. Moreover, ELISA assay and FCM shows a dose-dependent activation of p53 in MCF-7 cells treated with nanoHAP. These causative factors of the above results may be justified by an overproduction of ROS. In this study, a significant (p < 0.05) increase in the level of intracellular ROS in HAP-treated cells was observed. This study shows that HAP inhibits the growth of human breast cancer MCF-7 cells as well as induces cell apoptosis. This study shows that HAP NPs Induce the production of intracellular reactive oxygen species and activate p53, which may be responsible for DNA damage and cell apoptosis.

  1. [Effects of cucurmosin on the cell proliferation and apoptosis in human pancreatic PANC-1 cells].

    Science.gov (United States)

    Xu, Chun-Sen; Huang, He-Guang; Chen, Ming-Huang

    2012-02-01

    To observe the effects of cucurmosin (CUS) on the cell proliferation and apoptosis in pancreatic PANC-1 cells. The inhibition of CUS on the PANC-1 cell growth was observed using MTT assay. The inhibition ratio of CUS on the pancreatic orthotopic transplantation was in vivo observed in the NOD/SCID mouse model. The changes of microstructure of the apoptosis-inducing effect of CUS on PANC-1 was observed under electron microscope. The cell cycle and apoptosis after CUS intervention was detected using flow cytometry. The Caspase-3 activity after CUS treatment was detected using enzyme linked immunospecific assay (ELISA). Treatment with CUS at the dose of 0.125, 0.25, and 0.5 mg/kg inhibited the growth of pancreatic carcinoma PANC-1 xenografs with the ratio of 45.2%, 50.0%, and 59.7%, respectively (P PANC-1 cells in a dose-dependent maner. Being exposed to 40.0 microg/mL of the CUS for 24, 48, and 72 h, the percentage of G0/ G1 phase cells was 56.60% +/- 6.65%, 67.83% +/- 6.76%, and 77.00% +/- 6.73%, respectively (P PANC-1 cells in the G0/G1 phase of the cell cycle in a time-dependent maner. CUS significantly inhibited the growth of PANC-1 cells possibly through the G0/G1 cell cycle arrest and apoptosis.

  2. Acrolein-exposed normal human lung fibroblasts in vitro: cellular senescence, enhanced telomere erosion, and degradation of Werner's syndrome protein.

    Science.gov (United States)

    Jang, Jun-Ho; Bruse, Shannon; Huneidi, Salam; Schrader, Ronald M; Monick, Martha M; Lin, Yong; Carter, A Brent; Klingelhutz, Aloysius J; Nyunoya, Toru

    2014-09-01

    Acrolein is a ubiquitous environmental hazard to human health. Acrolein has been reported to activate the DNA damage response and induce apoptosis. However, little is known about the effects of acrolein on cellular senescence. We examined whether acrolein induces cellular senescence in cultured normal human lung fibroblasts (NHLF). We cultured NHLF in the presence or absence of acrolein and determined the effects of acrolein on cell proliferative capacity, senescence-associated β-galactosidase activity, the known senescence-inducing pathways (e.g., p53, p21), and telomere length. We found that acrolein induced cellular senescence by increasing both p53 and p21. The knockdown of p53 mediated by small interfering RNA (siRNA) attenuated acrolein-induced cellular senescence. Acrolein decreased Werner's syndrome protein (WRN), a member of the RecQ helicase family involved in DNA repair and telomere maintenance. Acrolein-induced down-regulation of WRN protein was rescued by p53 knockdown or proteasome inhibition. Finally, we found that acrolein accelerated p53-mediated telomere shortening. These results suggest that acrolein induces p53-mediated cellular senescence accompanied by enhanced telomere attrition and WRN protein down-regulation.

  3. The effect of quercetin nanoparticle on cervical cancer progression by inducing apoptosis, autophagy and anti-proliferation via JAK2 suppression.

    Science.gov (United States)

    Luo, Cheng-Lin; Liu, Yu-Qiong; Wang, Peng; Song, Chun-Hua; Wang, Kai-Juan; Dai, Li-Ping; Zhang, Jian-Ying; Ye, Hua

    2016-08-01

    Cervical cancer is a cause of cancer death, making it as the one of the most common cause for death among women globally. Though many studies before have explored a lot for cervical cancer prevention and treatment, there are still a lot far from to know based on the molecular mechanisms. Janus kinase 2 (JAK2) has been reported to play an essential role in the progression of apoptosis, autophagy and proliferation for cells. We loaded gold-quercetin into poly (dl-lactide-co-glycolide) nanoparticles to cervical cancer cells due to the propertities of quercetin in ameliorating cellular processes and the easier absorbance of nanoparticles. Here, in our study, quercetin nanoparticles (NQ) were administrated to cells to investigate the underlying mechanism by which the cervical cancer was regulated. First, JAK2-inhibited carvical cancer cell lines were involved for our experiments in vitro and in vivo. Western blotting, quantitative RT-PCR (qRT-PCR), ELISA, Immunohistochemistry, and flow-cytometric analysis were used to determine the key signaling pathway regulated by JAK2 for cervical cancer progression. And the role of quercetin nanoparticles was determined during the process. Data here indicated that JAK2, indeed, expressed highly in cancer cell lines compared to the normal cervical cells. And apoptosis and autophagy were found in JAK2-inhibited cancer cells through activating Caspase-3, and suppressing Cyclin-D1 and mTOR regulated by Signal Transducer and Activator of Transcription (STAT) 3/5 and phosphatidylinositide 3-kinase/protein kinases (PI3K/AKT) signaling pathway. The cervical cancer cells proliferation was inhibited. Further, tumor size and weight were reduced by inhibition of JAK2 in vivo experiments. Notably, administration with quercetin nanoparticles displayed similar role with JAK2 suppression, which could inhibit cervical cancer cells proliferation, invasion and migration. In addition, autophogy and apoptosis were induced, promoting cervical cancer cell

  4. Downregulation of long noncoding RNA TUG1 inhibits proliferation and induces apoptosis through the TUG1/miR-142/ZEB2 axis in bladder cancer cells

    Directory of Open Access Journals (Sweden)

    Liu Q

    2017-05-01

    Full Text Available Qian Liu,* Hui Liu,* Hepeng Cheng, Yang Li, Xiaodong Li, Chaoyang Zhu Department of Urology Surgery, Huaihe Hospital of Henan University, Kaifeng, People’s Republic of China *These authors contributed equally to this work Background: Bladder cancer is a common serious disease around the world. Long noncoding RNAs (lncRNAs have been demonstrated to participate in the development and progression of various cancers, including bladder cancer. The aim of this study was to investigate the effects of lncRNA taurine upregulated gene 1 (TUG1 on proliferation and apoptosis in bladder cancer cell lines and the underlying mechanism.Methods: The levels of TUG1 were detected by quantitative real time polymerase chain reaction (qRT-PCR in bladder cancer tissues and cells. The mRNA and protein levels of zinc finger E-box binding homeobox 2 (ZEB2 were measured by qRT-PCR and Western blot analysis, respectively. The functional targets of TUG1 were predicted by online softwares and confirmed by luciferase reporter assay. The effects of TUG1 on cell proliferation and apoptosis were examined by MTT and apoptosis assay, respectively. The expression levels of β-catenin, cyclinD1, and c-Myc in T24 cells were determined by Western blot analysis.Results: The levels of TUG1 and ZEB2 were significantly increased in bladder cancer tissues and cells. Knockdown of either TUG1 or ZEB2 inhibited proliferation and induced apoptosis in bladder cancer cells. Interestingly, ZEB2 overexpression reversed the effects of TUG1 knockdown on cell proliferation and apoptosis. Moreover, ZEB2 was verified as a direct target of miR-142 and miR-142 could specially bind to TUG1. In addition, downregulation of TUG1 inhibited the Wnt/β-catenin pathway by regulating ZEB2 expression in bladder cancer cells.Conclusion: Downregulation of TUG1 expression inhibited proliferation and induced apoptosis in bladder cancer cells by targeting ZEB2 mediated by miR-142 through the inactivation of Wnt

  5. A stochastic step model of replicative senescence explains ROS production rate in ageing cell populations.

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    Conor Lawless

    Full Text Available Increases in cellular Reactive Oxygen Species (ROS concentration with age have been observed repeatedly in mammalian tissues. Concomitant increases in the proportion of replicatively senescent cells in ageing mammalian tissues have also been observed. Populations of mitotic human fibroblasts cultured in vitro, undergoing transition from proliferation competence to replicative senescence are useful models of ageing human tissues. Similar exponential increases in ROS with age have been observed in this model system. Tracking individual cells in dividing populations is difficult, and so the vast majority of observations have been cross-sectional, at the population level, rather than longitudinal observations of individual cells.One possible explanation for these observations is an exponential increase in ROS in individual fibroblasts with time (e.g. resulting from a vicious cycle between cellular ROS and damage. However, we demonstrate an alternative, simple hypothesis, equally consistent with these observations which does not depend on any gradual increase in ROS concentration: the Stochastic Step Model of Replicative Senescence (SSMRS. We also demonstrate that, consistent with the SSMRS, neither proliferation-competent human fibroblasts of any age, nor populations of hTERT overexpressing human fibroblasts passaged beyond the Hayflick limit, display high ROS concentrations. We conclude that longitudinal studies of single cells and their lineages are now required for testing hypotheses about roles and mechanisms of ROS increase during replicative senescence.

  6. A stochastic step model of replicative senescence explains ROS production rate in ageing cell populations.

    Science.gov (United States)

    Lawless, Conor; Jurk, Diana; Gillespie, Colin S; Shanley, Daryl; Saretzki, Gabriele; von Zglinicki, Thomas; Passos, João F

    2012-01-01

    Increases in cellular Reactive Oxygen Species (ROS) concentration with age have been observed repeatedly in mammalian tissues. Concomitant increases in the proportion of replicatively senescent cells in ageing mammalian tissues have also been observed. Populations of mitotic human fibroblasts cultured in vitro, undergoing transition from proliferation competence to replicative senescence are useful models of ageing human tissues. Similar exponential increases in ROS with age have been observed in this model system. Tracking individual cells in dividing populations is difficult, and so the vast majority of observations have been cross-sectional, at the population level, rather than longitudinal observations of individual cells.One possible explanation for these observations is an exponential increase in ROS in individual fibroblasts with time (e.g. resulting from a vicious cycle between cellular ROS and damage). However, we demonstrate an alternative, simple hypothesis, equally consistent with these observations which does not depend on any gradual increase in ROS concentration: the Stochastic Step Model of Replicative Senescence (SSMRS). We also demonstrate that, consistent with the SSMRS, neither proliferation-competent human fibroblasts of any age, nor populations of hTERT overexpressing human fibroblasts passaged beyond the Hayflick limit, display high ROS concentrations. We conclude that longitudinal studies of single cells and their lineages are now required for testing hypotheses about roles and mechanisms of ROS increase during replicative senescence.

  7. Proliferation, apoptosis and their relationship to clinical outcome in cancer of the uterine cervix

    International Nuclear Information System (INIS)

    Shun, Wong; Tsang, Richard; Fyles, Anthony; Levin, Wilfred; Manchul, Lee; Milosevic, Michael; Li, Yu-qing; Chapman, William; Pintilie, Melania

    1997-01-01

    Purpose: To assess the prognostic value of pretreatment tumor proliferation and apoptosis in carcinoma of the cervix. Materials and Methods: Eighty-four patients were studied prospectively from Mar 1991 to Dec 1996. Pre-treatment evaluation included examination under anaesthesia and obtaining a biopsy specimen 4-10 hours following the intravenous administration of BrdUrd (200 mg). Potential doubling time (T pot ) was obtained by deriving the labelling index (LI) and S-phase duration (T s ) using flow cytometry (FC). LI and its staining pattern, mitotic index (MI), and apoptotic index (AI) were also determined on histology slides. Seven patients were excluded: 2 patients had no tumor in the biopsy specimen; 2 had a vaginal primary; and 3 did not receive radiation therapy (RT). The remaining 77 patients (median age 57 years, range 28-83) were treated with radical RT. There were 61 squamous, 11 adeno and 5 adenosquamous carcinomas. FIGO stages were: Ib and IIa, 20; IIb, 29; III and IV, 28, with a median tumor size of 6 cm. The median external beam dose was 50 Gy (range 40-52.8 Gy, 1 pt had 26 Gy and died of progressive disease) in 25 daily fractions, and the intracavitary dose was 40 Gy (single line source) specified at 2 cm lateral of the midline. The median overall treatment time was 45 days (range 38-73 days). Results: To date, 27 patients have died of disease, and the median follow-up for alive patients is 3.2 yr (range 0.4-6.0 yr). Three patients were not evaluable for response. There were 43 diploid and 34 aneuploid tumors. The median/mean LI by FC were (6.7%(7.9%)) (range 1.5-23.9%). The median/mean T pot were (5.0(6.7)) days (range 1.2-42.1 days). The median/mean AI were (1.0%(1.6%)) (range 0-6.8%). Among 64 patients who completely responded to treatment, 25 patients have relapsed (6 pelvic, 17 non-pelvic, and 2 pelvic and distant). Although there was a significant correlation between LI determined by FC vs. by histology (r=0.40), LI by histology was

  8. Phosphorylation of Histone H2AX in the Mouse Brain from Development to Senescence

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    Serena Barral

    2014-01-01

    Full Text Available Phosphorylation of the histone H2AX (γH2AX form is an early response to DNA damage and a marker of aging and disease in several cells and tissues outside the nervous system. Little is known about in vivo phosphorylation of H2AX in neurons, although it was suggested that γH2AX is an early marker of neuronal endangerment thus opening the possibility to target it as a neuroprotective strategy. After experimental labeling of DNA-synthesizing cells with 5-bromo-2-deoxyuridine (BrdU, we studied the brain occurrence of γH2AX in developing, postnatal, adult and senescent (2 years mice by light and electron microscopic immunocytochemistry and Western blotting. Focal and/or diffuse γH2AX immunostaining appears in interkinetic nuclei, mitotic chromosomes, and apoptotic nuclei. Immunoreactivity is mainly associated with neurogenetic areas, i.e., the subventricular zone (SVZ of telencephalon, the cerebellar cortex, and, albeit to a much lesser extent, the subgranular zone of the hippocampal dentate gyrus. In addition, γH2AX is highly expressed in the adult and senescent cerebral cortex, particularly the piriform cortex. Double labeling experiments demonstrate that γH2AX in neurogenetic brain areas is temporally and functionally related to proliferation and apoptosis of neuronal precursors, i.e., the type C transit amplifying cells (SVZ and the granule cell precursors (cerebellum. Conversely, γH2AX-immunoreactive cortical neurons incorporating the S phase-label BrdU do not express the proliferation marker phosphorylated histone H3, indicating that these postmitotic cells undergo a significant DNA damage response. Our study paves the way for a better comprehension of the role of H2AX phosphorylation in the normal brain, and offers additional data to design novel strategies for the protection of neuronal precursors and mature neurons in central nervous system (CNS degenerative diseases.

  9. Effects of resveratrol and other wine polyphenols on the proliferation, apoptosis and androgen receptor expression in LNCaP cells.

    Science.gov (United States)

    Ferruelo, A; Romero, I; Cabrera, P M; Arance, I; Andrés, G; Angulo, J C

    2014-01-01

    To address the effect of resveratrol and other red wine polyphenols on cell proliferation, apoptosis and androgen receptor (AR) expression in human prostate cancer LNCaP cells. LNCaP cells (5 × 102) were cultured in microtiter plate modules and treated with gallic acid, tannic acid and quercetin (1, 5 and 10 μM), rutin and morin (25, 50 and 75 μM) and resveratrol (5, 10 and 25 μM). To address the extent of proliferation at 24, 48, 72 and 96 hours, a colorimetric immunoassay method was used. An activity caspase 3/7 detection assay was used to disclose apoptosis at 24, 48 and 72 hours. AR mARN levels were determined by real time RT-PCR. All polyphenols studied significantly inhibited (P<.05) cell proliferation compared to control. However, there were moderate differences between them. Resveratrol was the strongest inhibitor at different times and doses. Also, caspase-3 and caspase-7 activity was significantly higher (P<.05) than control in the presence of all the compounds, but the earlier response was achieved by resveratrol. Resveratrol, quercetin and morin were the only nutrients that significantly inhibited AR mRNA expression. Again resveratrol produced the highest inhibition (90-250 times less than control), followed by morin (67-100 times) and quercetin (55-91 times). All polyphenols studied showed important antiproliferative effects and induced apoptosis when added to LNCaP cells culture. We confirm that resveratrol, morin and quercetin may achieve such effect through reduced expression of AR. The synergistic effects of these compounds and their potential to prevent progression of hormone-dependent prostate cancer merit further study. Copyright © 2014 AEU. Published by Elsevier Espana. All rights reserved.

  10. TASK-3 Downregulation Triggers Cellular Senescence and Growth Inhibition in Breast Cancer Cell Lines

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    Rafael Zúñiga

    2018-03-01

    Full Text Available TASK-3 potassium channels are believed to promote proliferation and survival of cancer cells, in part, by augmenting their resistance to both hypoxia and serum deprivation. While overexpression of TASK-3 is frequently observed in cancers, the understanding of its role and regulation during tumorigenesis remains incomplete. Here, we evaluated the effect of reducing the expression of TASK-3 in MDA-MB-231 and MCF-10F human mammary epithelial cell lines through small hairpin RNA (shRNA-mediated knockdown. Our results show that knocking down TASK-3 in fully transformed MDA-MB-231 cells reduces proliferation, which was accompanied by an induction of cellular senescence and cell cycle arrest, with an upregulation of cyclin-dependent kinase (CDK inhibitors p21 and p27. In non-tumorigenic MCF-10F cells, however, TASK-3 downregulation did not lead to senescence induction, although cell proliferation was impaired and an upregulation of CDK inhibitors was also evident. Our observations implicate TASK-3 as a critical factor in cell cycle progression and corroborate its potential as a therapeutic target in breast cancer treatment.

  11. High Leptin Level Attenuates Embryo Development in Overweight/Obese Infertile Women by Inhibiting Proliferation and Promotes Apoptosis in Granule Cell.

    Science.gov (United States)

    Lin, Xian-Hua; Wang, Hui; Wu, Dan-Dan; Ullah, Kamran; Yu, Tian-Tian; Ur Rahman, Tanzil; Huang, He-Feng

    2017-07-01

    Obesity appears to be associated with female reproductive dysfunction and infertility. Women with obesity undergoing in vitro fertilization (IVF) had poor oocyte quality, decreased embryo development, and poor pregnancy outcome. However, the mechanism linking obesity to poor reproductive outcomes is still unclear. Obesity is frequently accompanied with elevated leptin levels. Here we aimed to evaluate the effect of high leptin level in follicular fluid (FF) on the proliferation and apoptosis in granule cells and correlate these findings with poor reproductive outcomes in infertile women with overweight or obesity who underwent IVF treatment. We investigated clinical and ongoing pregnancy rates in 189 infertile women who underwent IVF. Leptin levels were quantified in peripheral blood and FF as well. In vitro cell model was used to explore the potential effect of high leptin on the proliferation and apoptosis in granulosa cells. Results showed reduced clinical and ongoing pregnancy rates in overweight/obesity women who underwent IVF compared to control with normal BMI. On the other hand, leptin levels presented significant increase in peripheral blood and FF in overweight/obese women. Leptin level in FF was negatively correlated to good quality embryo rate. Importantly, in vitro study showed that leptin inhibited cells proliferation and promoted apoptosis by upregulation of caspase-3 and downregulation of Bcl-2 in granulosa cells in a dose dependent manner. These observations suggest that leptin may acts as a local mediator to attenuate embryo development and reduce fertility in obese patients. © Georg Thieme Verlag KG Stuttgart · New York.

  12. FoxP3 inhibits proliferation and induces apoptosis of gastric cancer cells by activating the apoptotic signaling pathway

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    Ma, Gui-Fen [Department of Gastroenterology, Zhongshan Hospital, Fudan University, Shanghai (China); Chen, Shi-Yao, E-mail: shiyao_chen@163.com [Department of Gastroenterology, Zhongshan Hospital, Fudan University, Shanghai (China); Endoscopy Center, Zhongshan Hospital, Fudan University, Shanghai (China); Sun, Zhi-Rong [Department of Anesthesiology, Cancer Center, Fudan University, Shanghai (China); Miao, Qing; Liu, Yi-Mei; Zeng, Xiao-Qing; Luo, Tian-Cheng [Department of Gastroenterology, Zhongshan Hospital, Fudan University, Shanghai (China); Ma, Li-Li; Lian, Jing-Jing [Endoscopy Center, Zhongshan Hospital, Fudan University, Shanghai (China); Song, Dong-Li [Biomedical Research Center, Zhongshan Hospital, Fudan University, Shanghai (China)

    2013-01-11

    Highlights: Black-Right-Pointing-Pointer The article revealed FoxP3 gene function in gastric cancer firstly. Black-Right-Pointing-Pointer Present the novel roles of FoxP3 in inhibiting proliferation and promoting apoptosis in gastric cancer cells. Black-Right-Pointing-Pointer Overexpression of FoxP3 increased proapoptotic molecules and repressed antiapoptotic molecules. Black-Right-Pointing-Pointer Silencing of FoxP3 reduced the expression of proapoptotic genes, such as PARP, caspase-3 and caspase-9. Black-Right-Pointing-Pointer FoxP3 is sufficient for activating the apoptotic signaling pathway. -- Abstract: Forkhead Box Protein 3 (FoxP3) was identified as a key transcription factor to the occurring and function of the regulatory T cells (Tregs). However, limited evidence indicated its function in tumor cells. To elucidate the precise roles and underlying molecular mechanism of FoxP3 in gastric cancer (GC), we examined the expression of FoxP3 and the consequences of interfering with FoxP3 gene in human GC cell lines, AGS and MKN45, by multiple cellular and molecular approaches, such as immunofluorescence, gene transfection, CCK-8 assay, clone formation assay, TUNEL assay, Flow cytometry, immunoassay and quantities polymerase chain reaction (PCR). As a result, FoxP3 was expressed both in nucleus and cytoplasm of GC cells. Up-regulation of FoxP3 inhibited cell proliferation and promoted cell apoptosis. Overexpression of FoxP3 increased the protein and mRNA levels of proapoptotic molecules, such as poly ADP-ribose polymerase1 (PARP), caspase-3 and caspase-9, and repressed the expression of antiapoptotic molecules, such as cellular inhibitor of apoptosis-1 (c-IAP1) and the long isoform of B cell leukemia/lymphoma-2 (Bcl-2). Furthermore, silencing of FoxP3 by siRNA in GC cells reduced the expression of proapoptotic genes, such as PARP, caspase-3 and caspase-9. Collectively, our findings identify the novel roles of FoxP3 in inhibiting proliferation and inducing apoptosis

  13. Environmental stress, ageing and glial cell senescence: a novel mechanistic link to Parkinson's disease?

    Science.gov (United States)

    Chinta, S J; Lieu, C A; Demaria, M; Laberge, R-M; Campisi, J; Andersen, J K

    2013-05-01

    Exposure to environmental toxins is associated with a variety of age-related diseases including cancer and neurodegeneration. For example, in Parkinson's disease (PD), chronic environmental exposure to certain toxins has been linked to the age-related development of neuropathology. Neuronal damage is believed to involve the induction of neuroinflammatory events as a consequence of glial cell activation. Cellular senescence is a potent anti-cancer mechanism that occurs in a number of proliferative cell types and causes the arrest of proliferation of cells at risk of malignant transformation following exposure to potentially oncogenic stimuli. With age, senescent cells accumulate and express a senescence-associated secretory phenotype (SASP; that is the robust secretion of many inflammatory cytokines, growth factors and proteases). Whereas cell senescence in peripheral tissues has been causally linked to a number of age-related pathologies, little is known about the induction of cellular senescence and the SASP in the brain. On the basis of recently reported findings, we propose that environmental stressors associated with PD may act in part by eliciting senescence and the SASP within non neuronal glial cells in the ageing brain, thus contributing to the characteristic decline in neuronal integrity that occurs in this disorder. © 2013 The Association for the Publication of the Journal of Internal Medicine.

  14. Long non-coding RNA ANRIL is up-regulated in bladder cancer and regulates bladder cancer cell proliferation and apoptosis through the intrinsic pathway

    International Nuclear Information System (INIS)

    Zhu, Hongxue; Li, Xuechao; Song, Yarong; Zhang, Peng; Xiao, Yajun; Xing, Yifei

    2015-01-01

    Antisense non-coding RNA in the INK4 locus (ANRIL) is a member of long non-coding RNAs and has been reported to be dysregulated in several human cancers. However, the role of ANRIL in bladder cancer remains unclear. This present study aimed to investigate whether and how ANRIL involved in bladder cancer. Our results showed up-regulation of ANRIL in bladder cancer tissues versus the corresponding adjacent non-tumor tissues. To explore the specific mechanisms, ANRIL was silenced by small interfering RNA or short hairpin RNA transfection in human bladder cancer T24 and EJ cells. Knockdown of ANRIL repressed cell proliferation and increased cell apoptosis, along with decreased expression of Bcl-2 and increased expressions of Bax, cytoplasmic cytochrome c and Smac and cleaved caspase-9, caspase-3 and PARP. However, no change of cleaved caspase-8 level was observed. Furthermore, in vivo experiment confirmed that knockdown of ANRIL inhibited tumorigenic ability of EJ cells in nude mice. Meanwhile, in accordance with in vitro study, knockdown of ANRIL inhibited expression of Bcl-2 and up-regulated expressions of Bax and cleaved caspase-9, but did not affect cleaved caspase-8 level. In conclusion, we first report that ANRIL possibly serves as an oncogene in bladder cancer and regulates bladder cancer cell proliferation and apoptosis through the intrinsic apoptosis pathway. - Highlights: • We first report the role of ANRIL in bladder cancer. • ANRIL is obviously up-regulated in bladder cancer tissues. • ANRIL regulates bladder cancer cell proliferation and cell apoptosis through the intrinsic pathway.

  15. Evolution of plant senescence

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    Young Mike

    2009-07-01

    Full Text Available Abstract Background Senescence is integral to the flowering plant life-cycle. Senescence-like processes occur also in non-angiosperm land plants, algae and photosynthetic prokaryotes. Increasing numbers of genes have been assigned functions in the regulation and execution of angiosperm senescence. At the same time there has been a large expansion in the number and taxonomic spread of plant sequences in the genome databases. The present paper uses these resources to make a study of the evolutionary origins of angiosperm senescence based on a survey of the distribution, across plant and microbial taxa, and expression of senescence-related genes. Results Phylogeny analyses were carried out on protein sequences corresponding to genes with demonstrated functions in angiosperm senescence. They include proteins involved in chlorophyll catabolism and its control, homeoprotein transcription factors, metabolite transporters, enzymes and regulators of carotenoid metabolism and of anthocyanin biosynthesis. Evolutionary timelines for the origins and functions of particular genes were inferred from the taxonomic distribution of sequences homologous to those of angiosperm senescence-related proteins. Turnover of the light energy transduction apparatus is the most ancient element in the senescence syndrome. By contrast, the association of phenylpropanoid metabolism with senescence, and integration of senescence with development and adaptation mediated by transcription factors, are relatively recent innovations of land plants. An extended range of senescence-related genes of Arabidopsis was profiled for coexpression patterns and developmental relationships and revealed a clear carotenoid metabolism grouping, coordinated expression of genes for anthocyanin and flavonoid enzymes and regulators and a cluster pattern of genes for chlorophyll catabolism consistent with functional and evolutionary features of the pathway. Conclusion The expression and phylogenetic

  16. Biphasic effect of arsenite on cell proliferation and apoptosis is associated with the activation of JNK and ERK1/2 in human embryo lung fibroblast cells

    International Nuclear Information System (INIS)

    He Xiaoqing; Chen Rui; Yang Ping; Li Aiping; Zhou Jianwei; Liu Qizhan

    2007-01-01

    Biphasic dose-response relationship induced by environmental agents is often characterized with the effect of low-dose stimulation and high-dose inhibition. Some studies showed that arsenite may induce cell proliferation and apoptosis via biphasic dose-response relationship in human cells; however, mechanisms underlying this phenomenon are not well understood. In the present study, we aimed at investigating the relationship between biphasic effect of arsenite on cell proliferation and apoptosis and activation of JNK and ERK1/2 in human embryo lung fibroblast (HELF) cells. Our results demonstrated that cell proliferation may be stimulated at lower concentrations (0.1 and 0.5 μM) arsenite but inhibited at higher concentrations (5 and 10 μM). When cell apoptosis was used as the endpoint, the concentration-response curves were changed to U-shapes. During stimulation phospho-JNK levels were significantly increased at 3, 6, and 12 h after 0.1 or 0.5 μM arsenite exposure. Phospho-ERK1/2 levels were increased with different concentrations (0.1-10 μM) of arsenite at 6, 12, and 24 h. Blocking of JNK pathway with 20 μM SP600125 or ERK1/2 by 100 μM PD98059 significantly inhibited biphasic effect of arsenite in cells. Data in the present study suggest that activation of JNK and ERK1/2 may be involved in biphasic effect of arsenite when measuring cell proliferation and apoptosis in HELF cells. JNK activation seems to play a more critical role than ERK1/2 activation in the biphasic process

  17. Micro-environmental mechanical stress controls tumor spheroid size and morphology by suppressing proliferation and inducing apoptosis in cancer cells.

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    Gang Cheng

    Full Text Available Compressive mechanical stress produced during growth in a confining matrix limits the size of tumor spheroids, but little is known about the dynamics of stress accumulation, how the stress affects cancer cell phenotype, or the molecular pathways involved.We co-embedded single cancer cells with fluorescent micro-beads in agarose gels and, using confocal microscopy, recorded the 3D distribution of micro-beads surrounding growing spheroids. The change in micro-bead density was then converted to strain in the gel, from which we estimated the spatial distribution of compressive stress around the spheroids. We found a strong correlation between the peri-spheroid solid stress distribution and spheroid shape, a result of the suppression of cell proliferation and induction of apoptotic cell death in regions of high mechanical stress. By compressing spheroids consisting of cancer cells overexpressing anti-apoptotic genes, we demonstrate that mechanical stress-induced apoptosis occurs via the mitochondrial pathway.Our results provide detailed, quantitative insight into the role of micro-environmental mechanical stress in tumor spheroid growth dynamics, and suggest how tumors grow in confined locations where the level of solid stress becomes high. An important implication is that apoptosis via the mitochondrial pathway, induced by compressive stress, may be involved in tumor dormancy, in which tumor growth is held in check by a balance of apoptosis and proliferation.

  18. Differential senescence capacities in meibomian gland carcinoma and basal cell carcinoma.

    Science.gov (United States)

    Zhang, Leilei; Huang, Xiaolin; Zhu, Xiaowei; Ge, Shengfang; Gilson, Eric; Jia, Renbing; Ye, Jing; Fan, Xianqun

    2016-03-15

    Meibomian gland carcinoma (MGC) and basal cell carcinoma (BCC) are common eyelid carcinomas that exhibit highly dissimilar degrees of proliferation and prognoses. We address here the question of the differential mechanisms between these two eyelid cancers that explain their different outcome. A total of 102 confirmed MGC and 175 diagnosed BCC cases were analyzed. Twenty confirmed MGC and twenty diagnosed BCC cases were collected to determine the telomere length, the presence of senescent cells, and the expression levels of the telomere capping shelterin complex, P53, and the E3 ubiquitin ligase Siah1. Decreased protein levels of the shelterin subunits, shortened telomere length, over-expressed Ki-67, and Bcl2 as well as mutations in P53 were detected both in MGC and BCC. It suggests that the decreased protein levels of the shelterin complex and the shortened telomere length contribute to the tumorigenesis of MGC and BCC. However, several parameters distinguish MGC from BCC samples: (i) the mRNA level of the shelterin subunits decreased in MGC but it increased in BCC; (ii) P53 was more highly mutated in MGC; (iii) Siah1 mRNA was over-expressed in BCC; (iv) BCC samples contain a higher level of senescent cells; (v) Ki-67 and Bcl2 expression were lower in BCC. These results support a model where a preserved P53 checkpoint in BCC leads to cellular senescence and reduced tumor proliferation as compared to MGC. © 2015 UICC.

  19. IGF-I enhances cellular senescence via the reactive oxygen species-p53 pathway

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    Handayaningsih, Anastasia-Evi; Takahashi, Michiko; Fukuoka, Hidenori; Iguchi, Genzo; Nishizawa, Hitoshi; Yamamoto, Masaaki; Suda, Kentaro [Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe (Japan); Takahashi, Yutaka, E-mail: takahash@med.kobe-u.ac.jp [Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe (Japan)

    2012-08-24

    Highlights: Black-Right-Pointing-Pointer Cellular senescence plays an important role in tumorigenesis and aging process. Black-Right-Pointing-Pointer We demonstrated IGF-I enhanced cellular senescence in primary confluent cells. Black-Right-Pointing-Pointer IGF-I enhanced cellular senescence in the ROS and p53-dependent manner. Black-Right-Pointing-Pointer These results may explain the underlying mechanisms of IGF-I involvement in tumorigenesis and in regulation of aging. -- Abstract: Cellular senescence is characterized by growth arrest, enlarged and flattened cell morphology, the expression of senescence-associated {beta}-galactosidase (SA-{beta}-gal), and by activation of tumor suppressor networks. Insulin-like growth factor-I (IGF-I) plays a critical role in cellular growth, proliferation, tumorigenesis, and regulation of aging. In the present study, we show that IGF-I enhances cellular senescence in mouse, rat, and human primary cells in the confluent state. IGF-I induced expression of a DNA damage marker, {gamma}H2AX, the increased levels of p53 and p21 proteins, and activated SA-{beta}-gal. In the confluent state, an altered downstream signaling of IGF-I receptor was observed. Treatment with a reactive oxygen species (ROS) scavenger, N-acetylcystein (NAC) significantly suppressed induction of these markers, indicating that ROS are involved in the induction of cellular senescence by IGF-I. In p53-null mouse embryonic fibroblasts, the IGF-I-induced augmentation of SA-{beta}-gal and p21 was inhibited, demonstrating that p53 is required for cellular senescence induced by IGF-I. Thus, these data reveal a novel pathway whereby IGF-I enhances cellular senescence in the ROS and p53-dependent manner and may explain the underlying mechanisms of IGF-I involvement in tumorigenesis and in regulation of aging.

  20. IGF-I enhances cellular senescence via the reactive oxygen species–p53 pathway

    International Nuclear Information System (INIS)

    Handayaningsih, Anastasia-Evi; Takahashi, Michiko; Fukuoka, Hidenori; Iguchi, Genzo; Nishizawa, Hitoshi; Yamamoto, Masaaki; Suda, Kentaro; Takahashi, Yutaka

    2012-01-01

    Highlights: ► Cellular senescence plays an important role in tumorigenesis and aging process. ► We demonstrated IGF-I enhanced cellular senescence in primary confluent cells. ► IGF-I enhanced cellular senescence in the ROS and p53-dependent manner. ► These results may explain the underlying mechanisms of IGF-I involvement in tumorigenesis and in regulation of aging. -- Abstract: Cellular senescence is characterized by growth arrest, enlarged and flattened cell morphology, the expression of senescence-associated β-galactosidase (SA-β-gal), and by activation of tumor suppressor networks. Insulin-like growth factor-I (IGF-I) plays a critical role in cellular growth, proliferation, tumorigenesis, and regulation of aging. In the present study, we show that IGF-I enhances cellular senescence in mouse, rat, and human primary cells in the confluent state. IGF-I induced expression of a DNA damage marker, γH2AX, the increased levels of p53 and p21 proteins, and activated SA-β-gal. In the confluent state, an altered downstream signaling of IGF-I receptor was observed. Treatment with a reactive oxygen species (ROS) scavenger, N-acetylcystein (NAC) significantly suppressed induction of these markers, indicating that ROS are involved in the induction of cellular senescence by IGF-I. In p53-null mouse embryonic fibroblasts, the IGF-I-induced augmentation of SA-β-gal and p21 was inhibited, demonstrating that p53 is required for cellular senescence induced by IGF-I. Thus, these data reveal a novel pathway whereby IGF-I enhances cellular senescence in the ROS and p53-dependent manner and may explain the underlying mechanisms of IGF-I involvement in tumorigenesis and in regulation of aging.

  1. Resveratrol induces cellular senescence with attenuated mono-ubiquitination of histone H2B in glioma cells

    International Nuclear Information System (INIS)

    Gao, Zhen; Xu, Michael S.; Barnett, Tamara L.; Xu, C. Wilson

    2011-01-01

    Research highlights: → Resveratrol induces cellular senescence in glioma cell. → Resveratrol inhibits mono-ubiquitination of histone H2B at K120. → Depletion of RNF20, phenocopies the inhibitory effects of resveratrol. → Mono-ubiquitination of histone H2B at K120 is a novel target of resveratrol. → RNF20 inhibits cellular senescence in proliferating glioma cells. -- Abstract: Resveratrol (3,4',5-trihydroxy-trans-stilbene), a polyphenol naturally occurring in grapes and other plants, has cancer chemo-preventive effects and therapeutic potential. Although resveratrol modulates multiple pathways in tumor cells, how resveratrol or its affected pathways converge on chromatin to mediate its effects is not known. Using glioma cells as a model, we showed here that resveratrol inhibited cell proliferation and induced cellular hypertrophy by transforming spindle-shaped cells to enlarged, irregular and flatten-shaped ones. We further showed that resveratrol-induced hypertrophic cells expressed senescence-associated-β-galactosidase, suggesting that resveratrol-induced cellular senescence in glioma cells. Consistent with these observations, we demonstrated that resveratrol inhibited clonogenic efficiencies in vitro and tumor growth in a xenograft model. Furthermore, we found that acute treatment of resveratrol inhibited mono-ubiquitination of histone H2B at K120 (uH2B) in breast, prostate, pancreatic, lung, brain tumor cells as well as primary human cells. Chronic treatment with low doses of resveratrol also inhibited uH2B in the resveratrol-induced senescent glioma cells. Moreover, we showed that depletion of RNF20, a ubiquitin ligase of histone H2B, inhibited uH2B and induced cellular senescence in glioma cells in vitro, thereby recapitulated the effects of resveratrol. Taken together, our results suggest that uH2B is a novel direct or indirect chromatin target of resveratrol and RNF20 plays an important role in inhibiting cellular senescence programs that are

  2. Resveratrol induces cellular senescence with attenuated mono-ubiquitination of histone H2B in glioma cells

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Zhen; Xu, Michael S.; Barnett, Tamara L. [Nevada Cancer Institute, Las Vegas, NV 89135 (United States); Xu, C. Wilson, E-mail: wxu@nvcancer.org [Nevada Cancer Institute, Las Vegas, NV 89135 (United States)

    2011-04-08

    Research highlights: {yields} Resveratrol induces cellular senescence in glioma cell. {yields} Resveratrol inhibits mono-ubiquitination of histone H2B at K120. {yields} Depletion of RNF20, phenocopies the inhibitory effects of resveratrol. {yields} Mono-ubiquitination of histone H2B at K120 is a novel target of resveratrol. {yields} RNF20 inhibits cellular senescence in proliferating glioma cells. -- Abstract: Resveratrol (3,4',5-trihydroxy-trans-stilbene), a polyphenol naturally occurring in grapes and other plants, has cancer chemo-preventive effects and therapeutic potential. Although resveratrol modulates multiple pathways in tumor cells, how resveratrol or its affected pathways converge on chromatin to mediate its effects is not known. Using glioma cells as a model, we showed here that resveratrol inhibited cell proliferation and induced cellular hypertrophy by transforming spindle-shaped cells to enlarged, irregular and flatten-shaped ones. We further showed that resveratrol-induced hypertrophic cells expressed senescence-associated-{beta}-galactosidase, suggesting that resveratrol-induced cellular senescence in glioma cells. Consistent with these observations, we demonstrated that resveratrol inhibited clonogenic efficiencies in vitro and tumor growth in a xenograft model. Furthermore, we found that acute treatment of resveratrol inhibited mono-ubiquitination of histone H2B at K120 (uH2B) in breast, prostate, pancreatic, lung, brain tumor cells as well as primary human cells. Chronic treatment with low doses of resveratrol also inhibited uH2B in the resveratrol-induced senescent glioma cells. Moreover, we showed that depletion of RNF20, a ubiquitin ligase of histone H2B, inhibited uH2B and induced cellular senescence in glioma cells in vitro, thereby recapitulated the effects of resveratrol. Taken together, our results suggest that uH2B is a novel direct or indirect chromatin target of resveratrol and RNF20 plays an important role in inhibiting cellular

  3. FGFR3 regulates brain size by controlling progenitor cell proliferation and apoptosis during embryonic development.

    Science.gov (United States)

    Inglis-Broadgate, Suzanne L; Thomson, Rachel E; Pellicano, Francesca; Tartaglia, Michael A; Pontikis, Charlie C; Cooper, Jonathan D; Iwata, Tomoko

    2005-03-01

    Mice with the K644E kinase domain mutation in fibroblast growth factor receptor 3 (Fgfr3) (EIIa;Fgfr3(+/K644E)) exhibited a marked enlargement of the brain. The brain size was increased as early as E11.5, not secondary to the possible effect of Fgfr3 activity in the skeleton. Furthermore, the mutant brains showed a dramatic increase in cortical thickness, a phenotype opposite to that in FGF2 knockout mice. Despite this increased thickness, cortical layer formation was largely unaffected and no cortical folding was observed during embryonic days 11.5-18.5 (E11.5-E18.5). Measurement of cortical thickness revealed an increase of 38.1% in the EIIa;Fgfr3(+/K644E) mice at E14.5 and the advanced appearance of the cortical plate was frequently observed at this stage. Unbiased stereological analysis revealed that the volume of the ventricular zone (VZ) was increased by more than two fold in the EIIa;Fgfr3(+/K644E) mutants at E14.5. A relatively mild increase in progenitor cell proliferation and a profound decrease in developmental apoptosis during E11.5-E14.5 most likely accounts for the dramatic increase in total telecephalic cell number. Taken together, our data suggest a novel function of Fgfr3 in controlling the development of the cortex, by regulating proliferation and apoptosis of cortical progenitors.

  4. Delayed animal aging through the recovery of stem cell senescence by platelet rich plasma.

    Science.gov (United States)

    Liu, Hen-Yu; Huang, Chiung-Fang; Lin, Tzu-Chieh; Tsai, Ching-Yu; Tina Chen, Szu-Yu; Liu, Alice; Chen, Wei-Hong; Wei, Hong-Jian; Wang, Ming-Fu; Williams, David F; Deng, Win-Ping

    2014-12-01

    Aging is related to loss of functional stem cell accompanying loss of tissue and organ regeneration potentials. Previously, we demonstrated that the life span of ovariectomy-senescence accelerated mice (OVX-SAMP8) was significantly prolonged and similar to that of the congenic senescence-resistant strain of mice after platelet rich plasma (PRP)/embryonic fibroblast transplantation. The aim of this study is to investigate the potential of PRP for recovering cellular potential from senescence and then delaying animal aging. We first examined whether stem cells would be senescent in aged mice compared to young mice. Primary adipose derived stem cells (ADSCs) and bone marrow derived stem cells (BMSCs) were harvested from young and aged mice, and found that cell senescence was strongly correlated to animal aging. Subsequently, we demonstrated that PRP could recover cell potential from senescence, such as promote cell growth (cell proliferation and colony formation), increase osteogenesis, decrease adipogenesis, restore cell senescence related markers and resist the oxidative stress in stem cells from aged mice. The results also showed that PRP treatment in aged mice could delay mice aging as indicated by survival, body weight and aging phenotypes (behavior and gross morphology) in term of recovering the cellular potential of their stem cells compared to the results on aged control mice. In conclusion these findings showed that PRP has potential to delay aging through the recovery of stem cell senescence and could be used as an alternative medicine for tissue regeneration and future rejuvenation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Identification of 30 protein species involved in replicative senescence and stress-induced premature senescence

    DEFF Research Database (Denmark)

    Dierick, Jean François; Kalume, Dário E; Wenders, Frédéric

    2002-01-01

    Exposure of human proliferative cells to subcytotoxic stress triggers stress-induced premature senescence (SIPS) which is characterized by many biomarkers of replicative senescence. Proteomic comparison of replicative senescence and stress-induced premature senescence indicates that, at the level...

  6. A high ratio of apoptosis to proliferation correlates with improved survival after radiotherapy for cervical adenocarcinoma

    International Nuclear Information System (INIS)

    Sheridan, Mary T.; Cooper, Rachel A.; West, Catharine M.L.

    1999-01-01

    Purpose: A retrospective study was made of the role of apoptosis in determining radiotherapy outcome in 39 adenocarcinoma of the cervix. A comparison was also made of the detection of apoptosis by morphology and the TdT dUtp nick end-labeling (TUNEL) assay. Methods and Materials: The level of apoptosis was assessed in paraffin-embedded sections by cell morphology, the TUNEL assay, and a combination of the two. A total of 2,000 cells were counted per section, to obtain apoptotic (AI) and mitotic (MI) indices. Results: Patients with a high AI had a higher survival rate than those with a low AI, however, the difference was not significant. Using a ratio of apoptosis to proliferation indices, patients with an AI:MI > median had significantly better survival than those with AI:MI < median. This was true where the AI was quantified by morphology alone (p = 0.030) or in combination with the TUNEL assay (p = 0.008). Where the AI was quantified by a combination of morphology and TUNEL, the 5-year survival rates for women with AI:MI greater or less than the median were 81% and 25%, respectively. Conclusion: A high ratio of AI:MI in adenocarcinoma of the cervix indicates a good prognosis. A combination of the TUNEL assay and morphology provided the best discrimination between outcome groups

  7. Senescence-Induced Alterations of Laminin Chain Expression Modulate Tumorigenicity of Prostate Cancer Cells

    Directory of Open Access Journals (Sweden)

    Cynthia C.T. Sprenger

    2008-12-01

    Full Text Available Prostate cancer is an age-associated epithelial cancer, and as such, it contributes significantly to the mortality of the elderly. Senescence is one possible mechanism by which the body defends itself against various epithelial cancers. Senescent cells alter the microenvironment, in part, through changes to the extracellular matrix. Laminins (LMs are extracellular proteins important to both the structure and function of the microenvironment. Overexpression of the senescence-associated gene mac25 in human prostate cancer cells resulted in increased mRNA levels of the LM α4 and β2 chains compared to empty vector control cells. The purpose of this study was to examine the effects of these senescence-induced LM chains on tumorigenicity of prostate cancer cells. We created stable M12 human prostate cancer lines overexpressing either the LM α4 or β2 chain or both chains. Increased expression of either the LM α4 or β2 chain resulted in increased in vitro migration and in vivo tumorigenicity of those cells, whereas high expression of both chains led to decreased in vitro proliferation and in vivo tumorigenicity compared to M12 control cells. This study demonstrates that senescent prostate epithelial cells can alter the microenvironment and that these changes modulate progression of prostate cancer.

  8. Extracellular cystatin SN and cathepsin B prevent cellular senescence by inhibiting abnormal glycogen accumulation.

    Science.gov (United States)

    Oh, Sang-Seok; Park, Soojong; Lee, Ki-Won; Madhi, Hamadi; Park, Sae Gwang; Lee, Hee Gu; Cho, Yong-Yeon; Yoo, Jiyun; Dong Kim, Kwang

    2017-04-06

    Cystatin SN (CST1), a known inhibitor of cathepsin B (CatB), has important roles in tumor development. Paradoxically, CatB is a member of the cysteine cathepsin family that acts in cellular processes, such as tumor development and invasion. However, the relationship between CST1 and CatB, and their roles in tumor development are poorly understood. In this study, we observed that the knockdown of CST1 induced the activity of senescence-associated β-galactosidase, a marker of cellular senescence, and expression of senescence-associated secretory phenotype genes, including interleukin-6 and chemokine (C-C motif) ligand 20, in MDA-MB-231 and SW480 cancer cells. Furthermore, CST1 knockdown decreased extracellular CatB activity, and direct CatB inhibition, using specific inhibitors or shCatB, induced cellular senescence. Reconstitution of CST1 restored CatB activity and inhibited cellular senescence in CST1 knockdown cells. CST1 knockdown or CatB inhibition increased glycogen synthase (GS) kinase 3β phosphorylation at serine 9, resulting in the activation of GS and the induction of glycogen accumulation associated with cellular senescence. Importantly, CST1 knockdown suppressed cancer cell proliferation, soft agar colony growth and tumor growth in a xenograft model. These results indicate that CST1-mediated extracellular CatB activity enhances tumor development by preventing cellular senescence. Our findings suggest that antagonists of CST1 or inhibitors of CatB are potential anticancer agents.

  9. ΔNp63α is an oncogene that induces Lsh expression and promotes stem-like proliferation

    Science.gov (United States)

    Keyes, William M.; Pecoraro, Matteo; Aranda, Victoria; Vernersson-Lindahl, Emma; Li, Wangzhi; Vogel, Hannes; Guo, Xuecui; Garcia, Elvin L.; Michurina, Tatyana V.; Enikolopov, Grigori; Muthuswamy, Senthil K.; Mills, Alea A.

    2014-01-01

    SUMMARY The p53 homolog p63 is essential for development, yet its role in cancer is not clear. We discovered that p63 deficiency evokes the tumor suppressive mechanism of cellular senescence, causing a striking absence of stratified epithelia such as the skin. Here we identify the predominant p63 isoform, ΔNp63α, as a protein that bypasses oncogene induced senescence to drive tumorigenesis in vivo. Interestingly, bypass of senescence promotes stem-like proliferation and maintains survival of the keratin 15-positive stem cell population. Furthermore, we identify the chromatin remodeling protein Lsh as a new target of ΔNp63α that is an essential mediator of senescence bypass. These findings indicate that ΔNp63α is an oncogene that cooperates with Ras to promote tumor-initiating stem-like proliferation, and suggest that Lsh-mediated chromatin remodeling events are critical to this process. PMID:21295273

  10. Profile of cell proliferation and apoptosis activated by the intrinsic and extrinsic pathways in the prostate of aging rats.

    Science.gov (United States)

    Gonzaga, Amanda C R; Campolina-Silva, Gabriel H; Werneck-Gomes, Hipácia; Moura-Cordeiro, Júnia D; Santos, Letícia C; Mahecha, Germán A B; Morais-Santos, Mônica; Oliveira, Cleida A

    2017-06-01

    Estrogens acting through the receptors ERα and ERβ participate in prostate normal growth and cancer. ERβ is highly expressed in the prostate epithelium, playing pro-apoptotic, anti-proliferative, and pro-differentiation roles. Apoptosis is activated by the intrinsic pathway after castration and by the extrinsic pathway after ERβ agonist treatment. This differential activation of apoptotic pathways is important since a major problem in the treatment of prostate cancer is the recurrence of tumors after androgen withdrawal. However, a comprehensive study about the pattern of apoptosis in the aging prostate is lacking, a knowledge gap that we aimed to address herein. Cellular age-related proliferative and apoptotic profiles of prostate tissue obtained from aging Wistar rats were evaluated. Cell death (caspase-3, -8, -9, TNFα) was assessed by immunohistochemistry, immunofluorescence, and TUNEL. Cell proliferation (MCM7) and cell survival factors (ERK1/2, p-ERK1/2, p-Akt, and NF-κB) were determined by immunohistochemistry. As the rats aged, the number of proliferating cells gradually reduced in the normal epithelium of all prostate lobes, while increasing in focal areas of intraepithelial proliferation. Interestingly, in areas of intraepithelial proliferation, we observed a reduction in the number of cells positive for caspase-3, -8, and -9. Regardless the animal's age, few prostate epithelial cells were positive for caspase-3, caspase-9, and TUNEL. In contrast, a progressive increase was seen in the positivity for caspase-8, especially in the atrophic epithelium of ventral prostate, which coincided with a reduction in TNFα immunoreaction. However, morphology of most caspase-8 positive cells suggests that they were not apoptotic. We also found reduced ERβ expression in the same areas. Possibly, low levels of the pro-apoptotic inductors TNFα and ERβ direct caspase-8 activity to an alternative pro-survival role in the atrophic epithelium. This hypothesis is

  11. Vitamin E analogues inhibit angiogenesis by selective induction of apoptosis in proliferating endothelial cells: the role of oxidative stress

    Czech Academy of Sciences Publication Activity Database

    Dong, L.F.; Swettenham, E.; Eliasson, J.; Wang, X. F.; Gold, M.; Medunic, Y.; Stantic, M.; Low, P.; Procházka, L.; Witting, P. K.; Turánek, J.; Akporiaye, E.T.; Ralph, S.J.; Neužil, Jiří

    2007-01-01

    Roč. 67, č. 24 (2007), s. 11906-11913 ISSN 0008-5472 R&D Projects: GA AV ČR KAN200520703; GA AV ČR IAA500520602 Institutional research plan: CEZ:AV0Z50520514; CEZ:AV0Z50520701 Keywords : mitocans * proliferating endothelial cells * apoptosis Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 7.672, year: 2007

  12. Effects of IL-6 on proliferation and apoptosis of tumor cells multi-irradiated for tumor-bearing mice

    Energy Technology Data Exchange (ETDEWEB)

    Yongbiao, Liu [Chinese Academy of Sciences, Shanghai (China). Shanghai Inst. of Applied Physics; Xuzhou Medical Univ., Xuzhou (China); Side, Yao [Chinese Academy of Sciences, Shanghai (China). Shanghai Inst. of Applied Physics; Kai, Mei; Ying, Liu; Jie, Zhao; Xianwen, Zhang; Qiang, Zhou; Xingzhi, Hao [Xuzhou Medical Univ., Xuzhou (China)

    2004-05-15

    A study was carried out on effects of IL-6 on the proliferation and apoptosis of tumor cells and the expression of apoptosis relevant genes (p53, bcl-2) in tumor cells for three kinds of fractional total-body-irradiated tumor-bearing mice. The apoptotic index, proliferative index, S phase fraction of S{sub 180} sarcoma, H{sub 22} hepatocarcinoma and Lewis lung cancer cells were measured by flowcytometry (FCM) after total-body-irradiation and irradiation plus IL-6. The protein expression level of p53, bcl-2 in three kinds of tumors was also determined by the immunohisto-chemical method (UltraSensitive S-P). The results showed that the S phase fraction and proliferation index in Lewis lung cancer cells were lower in the irradiated plus IL-6 group than in the control, while apoptotic index was higher (P<0.05). However, the experimental results for S{sub 180} sarcoma cells were opposite (P<0.01). In addition, no significant effects were observed in H{sub 22} hepatocarcinoma. These results revealed that IL-6 promoted the apoptosis of irradiated Lewis lung cancer cells (P<0.05), while the apoptosis of S{sub 180} sarcoma (P<0.05) was restrained, and there was no significant effects on the cellular cycle of H{sub 22} hepatocarcinoma (P>0.05). In Lewis lung cancer the expression level of p53 was lower in the IL-6 group and higher in S{sub 180} sarcoma (P<0.05), while unvaried in H{sub 22} hepatocarcinoma as compared with the control (P>0.05). It is considered that tumor cell's proportion in the cellular cycle is changed by IL-6 and the effects of IL-6 on the expression of p53, bcl-2 in different three kinds of tumors are different. IL-6 has radio-sensitive effects on some tumors and opposite effects on other tumors, it may be related to the expression of p53 and bcl-2 in tumor cells. (authors)

  13. Environmental stress, ageing and glial cell senescence: a novel mechanistic link to Parkinson’s disease?

    Science.gov (United States)

    Chinta, Shankar J; Lieu, Christopher A; DeMaria, Marco; Laberge, Remi-Martin; Campisi, Judith; Andersen, Julie K

    2013-01-01

    Exposure to environmental toxins is associated with a variety of age-related diseases including cancer and neurodegeneration. For example, in Parkinson’s disease (PD), chronic environmental exposure to certain toxins has been linked to the age-related development of neuropathology. Neuronal damage is believed to involve the induction of neuroinflammatory events as a consequence of glial cell activation. Cellular senescence is a potent anti-cancer mechanism that occurs in a number of proliferative cell types and causes the arrest of proliferation of cells at risk of malignant transformation following exposure to potentially oncogenic stimuli. With age, senescent cells accumulate and express a senescence-associated secretory phenotype (SASP; i.e. the robust secretion of many inflammatory cytokines, growth factors and proteases). Whereas cell senescence in peripheral tissues has been causally linked to a number of age-related pathologies, little is known about the induction of cellular senescence and the SASP in the brain. Based on recently reported findings, we propose that environmental stressors associated with PD may act in part by eliciting senescence and the SASP within non-neuronal glial cells in the ageing brain, thus contributing to the characteristic decline in neuronal integrity that occurs in this disorder. PMID:23600398

  14. Human immunodeficiency virus envelope protein Gp120 induces proliferation but not apoptosis in osteoblasts at physiologic concentrations.

    Directory of Open Access Journals (Sweden)

    Nathan W Cummins

    Full Text Available Patients with HIV infection have decreased numbers of osteoblasts, decreased bone mineral density and increased risk of fracture compared to uninfected patients; however, the molecular mechanisms behind these associations remain unclear. We questioned whether Gp120, a component of the envelope protein of HIV capable of inducing apoptosis in many cell types, is able to induce cell death in bone-forming osteoblasts. We show that treatment of immortalized osteoblast-like cells and primary human osteoblasts with exogenous Gp120 in vitro at physiologic concentrations does not result in apoptosis. Instead, in the osteoblast-like U2OS cell line, cells expressing CXCR4, a receptor for Gp120, had increased proliferation when treated with Gp120 compared to control (P<0.05, which was inhibited by pretreatment with a CXCR4 inhibitor and a G-protein inhibitor. This suggests that Gp120 is not an inducer of apoptosis in human osteoblasts and likely does not directly contribute to osteoporosis in infected patients by this mechanism.

  15. Effects of IL-6 on proliferation and apoptosis of tumor cells multi-irradiated for tumor-bearing mice

    International Nuclear Information System (INIS)

    Liu Yongbiao; Yao Side

    2004-01-01

    A study was carried out on effects of IL-6 on the proliferation and apoptosis of tumor cells and the expression of apoptosis relevant genes (p53, bcl-2) in tumor cells for three kinds of fractional total-body-irradiated tumor-bearing mice. The apoptotic index, proliferative index, S phase fraction of S 180 sarcoma, H 22 hepatocarcinoma and Lewis lung cancer cells were measured by flowcytometry (FCM) after total-body-irradiation and irradiation plus IL-6. The protein expression level of p53, bcl-2 in three kinds of tumors was also determined by the immunohisto-chemical method (UltraSensitive S-P). The results showed that the S phase fraction and proliferation index in Lewis lung cancer cells were lower in the irradiated plus IL-6 group than in the control, while apoptotic index was higher (P 180 sarcoma cells were opposite (P 22 hepatocarcinoma. These results revealed that IL-6 promoted the apoptosis of irradiated Lewis lung cancer cells (P 180 sarcoma (P 22 hepatocarcinoma (P>0.05). In Lewis lung cancer the expression level of p53 was lower in the IL-6 group and higher in S 180 sarcoma (P 22 hepatocarcinoma as compared with the control (P>0.05). It is considered that tumor cell's proportion in the cellular cycle is changed by IL-6 and the effects of IL-6 on the expression of p53, bcl-2 in different three kinds of tumors are different. IL-6 has radio-sensitive effects on some tumors and opposite effects on other tumors, it may be related to the expression of p53 and bcl-2 in tumor cells. (authors)

  16. Senescence and quiescence in adipose-derived stromal cells: Effects of human platelet lysate, fetal bovine serum and hypoxia.

    Science.gov (United States)

    Søndergaard, Rebekka Harary; Follin, Bjarke; Lund, Lisbeth Drozd; Juhl, Morten; Ekblond, Annette; Kastrup, Jens; Haack-Sørensen, Mandana

    2017-01-01

    Adipose-derived stromal cells (ASCs) are attractive sources for cell-based therapies. The hypoxic niche of ASCs in vivo implies that cells will benefit from hypoxia during in vitro expansion. Human platelet lysate (hPL) enhances ASC proliferation rates, compared with fetal bovine serum (FBS) at normoxia. However, the low proliferation rates of FBS-expanded ASCs could be signs of senescence or quiescence. We aimed to determine the effects of hypoxia and hPL on the expansion of ASCs and whether FBS-expanded ASCs are senescent or quiescent. ASCs expanded in FBS or hPL at normoxia or hypoxia until passage 7 (P7), or in FBS until P5 followed by culture in hPL until P7, were evaluated by proliferation rates, cell cycle analyses, gene expression and β-galactosidase activity. hPL at normoxia and hypoxia enhanced proliferation rates and expression of cyclins, and decreased G0/G1 fractions and expression of p21 and p27, compared with FBS. The shift from FBS to hPL enhanced cyclin levels, decreased p21 and p27 levels and tended to decrease G0/G1 fractions. Hypoxia does not add to the effect of hPL during ASC expansion with regard to proliferation, cell cycle regulation and expression of cyclins, p21 and p27. hPL rejuvenates FBS-expanded ASCs with regard to cell cycle regulation and expression of cyclins, p21 and p27. This indicates a reversible arrest. Therefore, we conclude that ASCs expanded until P7 are not senescent regardless of culture conditions. Copyright © 2017 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

  17. Senescence and programmed cell death in plants: polyamine action mediated by transglutaminase

    Directory of Open Access Journals (Sweden)

    Stefano eDel Duca

    2014-04-01

    Full Text Available Research on polyamines in plants laps a long way of about 50 years and many roles have been discovered for these aliphatic cations. Polyamines regulate cell division, differentiation, organogenesis, reproduction, dormancy-break and senescence, homeostatic adjustments in response to external stimuli and stresses. Nevertheless, the molecular mechanisms of their multiple activities are still matter of research. Polyamines are present in free and bound forms and interact with several important cell molecules; some of these interactions may occur by covalent linkages catalyzed by transglutaminase, giving rise to ‘cationisation’ or cross-links among specific proteins. Senescence and PCD can be delayed by polyamines; in order to re-interpret some of these effects and to obtain new insights into their molecular mechanisms, their conjugation has been revised here. The transglutaminase-mediated interactions between proteins and polyamines are the main target of this review. After an introduction on the characteristics of this enzyme, on its catalysis and role in PCD in animals, the plant senescence and PCD models in which TGase has been studied, are presented: the corolla of naturally senescing or excised flowers, the leaves senescing, either excised or not, the pollen during self-incompatible pollination, the hypersensitive response and the tuber storage parenchyma during dormancy release. In all the models examined, transglutaminase appears to be involved by a similar molecular mechanism as described during apoptosis in animal cells, even though several substrates are different. Its effect is probably related to the type of PCD, but mostly to the substrate to be modified in order to achieve the specific PCD program. As a cross-linker of polyamines and proteins, transglutaminase is an important factor involved in multiple, sometimes controversial, roles of polyamines during senescence and PCD.

  18. The Immortal Senescence.

    Science.gov (United States)

    Bianchi-Smiraglia, Anna; Lipchick, Brittany C; Nikiforov, Mikhail A

    2017-01-01

    Activation of oncogenic signaling paradoxically results in the permanent withdrawal from cell cycle and induction of senescence (oncogene-induced senescence (OIS)). OIS is a fail-safe mechanism used by the cells to prevent uncontrolled tumor growth, and, as such, it is considered as the first barrier against cancer. In order to progress, tumor cells thus need to first overcome the senescent phenotype. Despite the increasing attention gained by OIS in the past 20 years, this field is still rather young due to continuous emergence of novel pathways and processes involved in OIS. Among the many factors contributing to incomplete understanding of OIS are the lack of unequivocal markers for senescence and the complexity of the phenotypes revealed by senescent cells in vivo and in vitro. OIS has been shown to play major roles at both the cellular and organismal levels in biological processes ranging from embryonic development to barrier to cancer progression. Here we will briefly outline major advances in methodologies that are being utilized for induction, identification, and characterization of molecular processes in cells undergoing oncogene-induced senescence. The full description of such methodologies is provided in the corresponding chapters of the book.

  19. BCG strain S4-Jena: An early BCG strain is capable to reduce the proliferation of bladder cancer cells by induction of apoptosis

    Directory of Open Access Journals (Sweden)

    Hermann Inge-Marie

    2010-06-01

    Full Text Available Abstract Background Intravesical immunotherapy with Mycobacterium bovis bacillus Calmette-Guérin has been established as the most effective adjuvant treatment for high risk non-muscle-invasive bladder cancer (NMIBC. We investigated the differences between the S4-Jena BCG strain and commercially available BCG strains. We tested the genotypic varieties between S4-Jena and other BCG strains and analysed the effect of the BCG strains TICE and S4-Jena on two bladder cancer cell lines. Results In contrast to commercially available BCG strains the S4-Jena strain shows genotypic differences. Spoligotyping verifies the S4-Jena strain as a BCG strain. Infection with viable S4-Jena or TICE decreased proliferation in the T24 cell line. Additionally, hallmarks of apoptosis were detectable. In contrast, Cal29 cells showed only a slightly decreased proliferation with TICE. Cal29 cells infected with S4-Jena, though, showed a significantly decreased proliferation in contrast to TICE. Concordantly with these results, infection with TICE had no effect on the morphology and hallmarks of apoptosis of Cal29 cells. However, S4-Jena strain led to clearly visible morphological changes and caspases 3/7 activation and PS flip. Conclusions S4-Jena strain has a direct influence on bladder cancer cell lines as shown by inhibition of cell proliferation and induction of apoptosis. The data implicate that the T24 cells are responder for S4-Jena and TICE BCG. However, the Cal29 cells are only responder for S4-Jena and they are non-responder for TICE BCG. S4-Jena strain may represent an effective therapeutic agent for NMIBC.

  20. BRD4 regulates cellular senescence in gastric cancer cells via E2F/miR-106b/p21 axis.

    Science.gov (United States)

    Dong, Xingchen; Hu, Xiangming; Chen, Jinjing; Hu, Dan; Chen, Lin-Feng

    2018-02-12

    Small molecules targeting bromodomains of BET proteins possess strong anti-tumor activities and have emerged as potential therapeutics for cancer. However, the underlying mechanisms for the anti-proliferative activity of these inhibitors are still not fully characterized. In this study, we demonstrated that BET inhibitor JQ1 suppressed the proliferation and invasiveness of gastric cancer cells by inducing cellular senescence. Depletion of BRD4, which was overexpressed in gastric cancer tissues, but not other BET proteins recapitulated JQ1-induced cellular senescence with increased cellular SA-β-Gal activity and elevated p21 levels. In addition, we showed that the levels of p21 were regulated at the post-transcriptional level by BRD4-dependent expression of miR-106b-5p, which targets the 3'-UTR of p21 mRNA. Overexpression of miR-106b-5p prevented JQ1-induced p21 expression and BRD4 inhibition-associated cellular senescence, whereas miR-106b-5p inhibitor up-regulated p21 and induced cellular senescence. Finally, we demonstrated that inhibition of E2F suppressed the binding of BRD4 to the promoter of miR-106b-5p and inhibited its transcription, leading to the increased p21 levels and cellular senescence in gastric cancer cells. Our results reveal a novel mechanism by which BRD4 regulates cancer cell proliferation by modulating the cellular senescence through E2F/miR-106b-5p/p21 axis and provide new insights into using BET inhibitors as potential anticancer drugs.

  1. The p53-reactivating small molecule RITA induces senescence in head and neck cancer cells.

    Science.gov (United States)

    Chuang, Hui-Ching; Yang, Liang Peng; Fitzgerald, Alison L; Osman, Abdullah; Woo, Sang Hyeok; Myers, Jeffrey N; Skinner, Heath D

    2014-01-01

    TP53 is the most commonly mutated gene in head and neck cancer (HNSCC), with mutations being associated with resistance to conventional therapy. Restoring normal p53 function has previously been investigated via the use of RITA (reactivation of p53 and induction of tumor cell apoptosis), a small molecule that induces a conformational change in p53, leading to activation of its downstream targets. In the current study we found that RITA indeed exerts significant effects in HNSCC cells. However, in this model, we found that a significant outcome of RITA treatment was accelerated senescence. RITA-induced senescence in a variety of p53 backgrounds, including p53 null cells. Also, inhibition of p53 expression did not appear to significantly inhibit RITA-induced senescence. Thus, this phenomenon appears to be partially p53-independent. Additionally, RITA-induced senescence appears to be partially mediated by activation of the DNA damage response and SIRT1 (Silent information regulator T1) inhibition, with a synergistic effect seen by combining either ionizing radiation or SIRT1 inhibition with RITA treatment. These data point toward a novel mechanism of RITA function as well as hint to its possible therapeutic benefit in HNSCC.

  2. Salinomycin inhibits proliferation and induces apoptosis of human nasopharyngeal carcinoma cell in vitro and suppresses tumor growth in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Danxin; Zhang, Yu; Huang, Jie; Fan, Zirong; Shi, Fengrong; Wang, Senming, E-mail: wsenming@126.com

    2014-01-10

    Highlight: •We first evaluated the effect of salinomycin on nasopharyngeal carcinoma (NPC). •Salinomycin could inhibit Wnt/β-catenin signaling and induce apoptosis in NPC. •So salinomycin may be a good potential candidate for the chemotherapy of NPC. -- Abstract: Salinomycin (Sal) is a polyether ionophore antibiotic that has recently been shown to induce cell death in various human cancer cells. However, whether salinomycin plays a functional role in nasopharyngeal carcinoma (NPC) has not been determined to date. The present study investigated the chemotherapeutic efficacy of salinomycin and its molecular mechanisms of action in NPC cells. Salinomycin efficiently inhibited proliferation and invasion of 3 NPC cell lines (CNE-1, CNE-2, and CNE-2/DDP) and activated a extensive apoptotic process that is accompanied by activation of caspase-3 and caspase-9, and decreased mitochondrial membrane potential. Meanwhile, the protein expression level of the Wnt coreceptor lipoprotein receptor related protein 6 (LRP6) and β-catenin was down-regulated, which showed that the Wnt/β-catenin signaling was involved in salinomycin-induced apoptosis of NPC cells. In a nude mouse NPC xenograft model, the anti-tumor effect of salinomycin was associated with the downregulation of β-catenin expression. The present study demonstrated that salinomycin can effectively inhibit proliferation and invasion, and induce apoptosis of NPC cells in vitro and inhibit tumor growth in vivo, probably via the inhibition of Wnt/β-catenin signaling, suggesting salinomycin as a potential candidate for the chemotherapy of NPC.

  3. Senescence is not inevitable

    DEFF Research Database (Denmark)

    Jones, Owen; Vaupel, James W.

    2017-01-01

    trajectories exists. These empirical observations support theoretical work indicating that a wide range of mortality and fertility trajectories is indeed possible, including senescence, negligible senescence and even negative senescence (improvement). Although many mysteries remain in the field...

  4. Cordycepin Induces Apoptosis and Inhibits Proliferation of Human Lung Cancer Cell Line H1975 via Inhibiting the Phosphorylation of EGFR

    Directory of Open Access Journals (Sweden)

    Zheng Wang

    2016-09-01

    Full Text Available Cordycepin is an active component of the traditional Chinese medicine Cordyceps sinensis and Cordyceps militaris with notable anticancer activity. Though the prominent inhibitory activity was reported in different kinds of cancer cell lines, the concrete mechanisms remain elusive. It was reported that cordycepin could be converted into tri-phosphates in vivo to confuse a number of enzymes and interfere the normal cell function. For the inhibitory mechanism of EGFR inhibitors and the structure similarity of ATP and tri-phosphated cordycepin, human lung cancer cell line H1975 was employed to investigate the inhibitory effect of cordycepin. The results showed that cordycepin could inhibit cell proliferation and induce apoptosis in a dose-dependent manner. Cell cycle analysis revealed that H1975 cells could be arrested at the G0/G1 phase after cordycepin treatment. The expression levels of apoptosis-related protein Caspase-3 and Bcl-2 and phosphorylated expression levels of EGFR, AKT and ERK1/2 were all decreased compared with the control group stimulated with EGF. However, the protein expression levels of proapoptotic protein Bax and cleaved caspase-3 were increased. These results implied that cordycepin could inhibit cell proliferation and induce apoptosis via the EGFR signaling pathway. Our results indicated that there was potential to seek a novel EGFR inhibitor from cordycepin and its chemical derivatives.

  5. Interferon-β induces cellular senescence in cutaneous human papilloma virus-transformed human keratinocytes by affecting p53 transactivating activity.

    Directory of Open Access Journals (Sweden)

    Maria V Chiantore

    Full Text Available Interferon (IFN-β inhibits cell proliferation and affects cell cycle in keratinocytes transformed by both mucosal high risk Human Papilloma Virus (HPV and cutaneous HPV E6 and E7 proteins. In particular, upon longer IFN-β treatments, cutaneous HPV38 expressing cells undergo senescence. IFN-β appears to induce senescence by upregulating the expression of the tumor suppressor PML, a well known IFN-induced gene. Indeed, experiments in gene silencing via specific siRNAs have shown that PML is essential in the execution of the senescence programme and that both p53 and p21 pathways are involved. IFN-β treatment leads to a modulation of p53 phosphorylation and acetylation status and a reduction in the expression of the p53 dominant negative ΔNp73. These effects allow the recovery of p53 transactivating activity of target genes involved in the control of cell proliferation. Taken together, these studies suggest that signaling through the IFN pathway might play an important role in cellular senescence. This additional understanding of IFN antitumor action and mechanisms influencing tumor responsiveness or resistance appears useful in aiding further promising development of biomolecular strategies in the IFN therapy of cancer.

  6. N-Cadherin Attenuates High Glucose-Induced Nucleus Pulposus Cell Senescence Through Regulation of the ROS/NF-κB Pathway.

    Science.gov (United States)

    Hou, Gang; Zhao, Huiqing; Teng, Haijun; Li, Pei; Xu, Wenbin; Zhang, Junbin; Lv, Lulu; Guo, Zhiliang; Wei, Li; Yao, Hui; Xu, Yichun

    2018-05-11

    Diabetes mellitus (DM) is a potential etiology of disc degeneration. N-cadherin (N-CDH) helps maintain the cell viability, cell phenotype and matrix biosynthesis of nucleus pulposus (NP) cells. Here, we mainly aimed to investigate whether N-CDH can attenuate high glucose-induced NP cell senescence and its potential mechanism. Rat NP cells were cultured in a base culture medium and base culture medium with a 0.2 M glucose concentration. Recombinant lentiviral vectors were used to enhance N-CDH expression in NP cells. Senescence-associated β-galactosidase (SA-β-Gal) activity was measured by SA-β-Gal staining. NP cell proliferation was evaluated by CCK-8 assay. Telomerase activity and intracellular reactive oxygen species (ROS) content were tested by specific chemical kits according to the manufacturer's instructions. G0/G1 cell cycle arrest was evaluated by flow cytometry. Real-time PCR and Western blotting were used to analyze mRNA and protein expressions of senescence markers (p16 and p53) and matrix macromolecules (aggrecan and collagen II). Additionally, p-NF-κB expression was also analyzed by Western blotting to evaluate NF-κB pathway activity. High glucose significantly decreased N-CDH expression, increased ROS generation and NF-κB pathway activity, and promoted NP cell senescence, which was reflected in the increase in SA-β-Gal activity and senescence marker (p16 and p53) expression, compared to the control group. High glucose decreased telomerase activity and cell proliferation potency. However, N-CDH overexpression partially attenuated NP cell senescence, decreased ROS content and inhibited the activation of the NF-κB pathway under the high glucose condition. High glucose decreases N-CDH expression and promotes NP cell senescence. N-CDH overexpression can attenuate high glucose-induced NP cell senescence through the regulation of the ROS/ NF-κB pathway. This study suggests that N-CDH is a potential therapeutic target to slow DM-mediated disc NP

  7. The SETD8/PR-Set7 Methyltransferase Functions as a Barrier to Prevent Senescence-Associated Metabolic Remodeling

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    Hiroshi Tanaka

    2017-02-01

    Full Text Available Summary: Cellular senescence is an irreversible growth arrest that contributes to development, tumor suppression, and age-related conditions. Senescent cells show active metabolism compared with proliferating cells, but the underlying mechanisms remain unclear. Here we show that the SETD8/PR-Set7 methyltransferase, which catalyzes mono-methylation of histone H4 at lysine 20 (H4K20me1, suppresses nucleolar and mitochondrial activities to prevent cellular senescence. SETD8 protein was selectively downregulated in both oncogene-induced and replicative senescence. Inhibition of SETD8 alone was sufficient to trigger senescence. Under these states, the expression of genes encoding ribosomal proteins (RPs and ribosomal RNAs as well as the cyclin-dependent kinase (CDK inhibitor p16INK4A was increased, with a corresponding reduction of H4K20me1 at each locus. As a result, the loss of SETD8 concurrently stimulated nucleolar function and retinoblastoma protein-mediated mitochondrial metabolism. In conclusion, our data demonstrate that SETD8 acts as a barrier to prevent cellular senescence through chromatin-mediated regulation of senescence-associated metabolic remodeling. : Tanaka et al. show that SETD8/PR-Set7 methyltransferase represses senescence-associated genes including ribosomal proteins, ribosomal RNAs, and p16INK4A by catalyzing mono-methylation of histone H4 at lysine 20. Depletion of SETD8 derepresses these genes, resulting in nucleolar and mitochondrial coactivation characteristic of senescence-associated metabolic remodeling. Keywords: SETD8/PR-Set7, H4K20 methylation, senescence-associated metabolic remodeling, nucleolus, mitochondria

  8. Effects of high glucose on mesenchymal stem cell proliferation and differentiation

    DEFF Research Database (Denmark)

    Li, Yu-Ming; Schilling, Tatjana; Benisch, Peggy

    2007-01-01

    High glucose (HG) concentrations impair cellular functions and induce apoptosis. Exposition of mesenchymal stem cells (MSC) to HG was reported to reduce colony forming activity and induce premature senescence. We characterized the effects of HG on human MSC in vitro using telomerase-immortalized...

  9. Titanium dioxide nanoparticles inhibit proliferation and induce morphological changes and apoptosis in glial cells

    International Nuclear Information System (INIS)

    Márquez-Ramírez, Sandra Gissela; Delgado-Buenrostro, Norma Laura; Chirino, Yolanda Irasema; Iglesias, Gisela Gutiérrez; López-Marure, Rebeca

    2012-01-01

    Titanium dioxide nanoparticles (TiO 2 NPs) are widely used in the chemical, electrical and electronic industries. TiO 2 NPs can enter directly into the brain through the olfactory bulb and be deposited in the hippocampus region. We determined the effect of TiO 2 NPs on rat and human glial cells, C6 and U373, respectively. We evaluated proliferation by crystal violet staining, internalization of TiO 2 NPs, and cellular morphology by TEM analysis, as well as F-actin distribution by immunostaining and cell death by detecting active caspase-3 and DNA fragmentation. TiO 2 NPs inhibited proliferation and induced morphological changes that were related with a decrease in immuno-location of F-actin fibers. TiO 2 NPs were internalized and formation of vesicles was observed. TiO 2 NPs induced apoptosis after 96 h of treatment. Hence, TiO 2 NPs had a cytotoxic effect on glial cells, suggesting that exposure to TiO 2 NPs could cause brain injury and be hazardous to health.

  10. HIV and drug abuse mediate astrocyte senescence in a β-catenin-dependent manner leading to neuronal toxicity.

    Science.gov (United States)

    Yu, Chunjiang; Narasipura, Srinivas D; Richards, Maureen H; Hu, Xiu-Ti; Yamamoto, Bryan; Al-Harthi, Lena

    2017-10-01

    Emerging evidence suggests that cell senescence plays an important role in aging-associated diseases including neurodegenerative diseases. HIV leads to a spectrum of neurologic diseases collectively termed HIV-associated neurocognitive disorders (HAND). Drug abuse, particularly methamphetamine (meth), is a frequently abused psychostimulant among HIV+ individuals and its abuse exacerbates HAND. The mechanism by which HIV and meth lead to brain cell dysregulation is not entirely clear. In this study, we evaluated the impact of HIV and meth on astrocyte senescence using in vitro and several animal models. Astrocytes constitute up to 50% of brain cells and play a pivotal role in marinating brain homeostasis. We show here that HIV and meth induce significant senescence of primary human fetal astrocytes, as evaluated by induction of senescence markers (β-galactosidase and p16 INK 4A ), senescence-associated morphologic changes, and cell cycle arrest. HIV- and meth-mediated astrocyte senescence was also demonstrated in three small animal models (humanized mouse model of HIV/NSG-huPBMCs, HIV-transgenic rats, and in a meth administration rat model). Senescent astrocytes in turn mediated neuronal toxicity. Further, we show that β-catenin, a pro-survival/proliferation transcriptional co-activator, is downregulated by HIV and meth in human astrocytes and this downregulation promotes astrocyte senescence while induction of β-catenin blocks HIV- and meth-mediated astrocyte senescence. These studies, for the first time, demonstrate that HIV and meth induce astrocyte senescence and implicate the β-catenin pathway as potential therapeutic target to overcome astrocyte senescence. © 2017 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

  11. Senescence-Induced Alterations of Laminin Chain Expression Modulate Tumorigenicity of Prostate Cancer Cells1

    Science.gov (United States)

    Sprenger, Cynthia C T; Drivdahl, Rolf H; Woodke, Lillie B; Eyman, Daniel; Reed, May J; Carter, William G; Plymate, Stephen R

    2008-01-01

    Prostate cancer is an age-associated epithelial cancer, and as such, it contributes significantly to the mortality of the elderly. Senescence is one possible mechanism by which the body defends itself against various epithelial cancers. Senescent cells alter the microenvironment, in part, through changes to the extracellular matrix. Laminins (LMs) are extracellular proteins important to both the structure and function of the microenvironment. Overexpression of the senescence-associated gene mac25 in human prostate cancer cells resulted in increased mRNA levels of the LM α4 and β2 chains compared to empty vector control cells. The purpose of this study was to examine the effects of these senescence-induced LM chains on tumorigenicity of prostate cancer cells. We created stable M12 human prostate cancer lines overexpressing either the LM α4 or β2 chain or both chains. Increased expression of either the LM α4 or β2 chain resulted in increased in vitro migration and in vivo tumorigenicity of those cells, whereas high expression of both chains led to decreased in vitro proliferation and in vivo tumorigenicity compared to M12 control cells. This study demonstrates that senescent prostate epithelial cells can alter the microenvironment and that these changes modulate progression of prostate cancer. PMID:19048114

  12. Regulation of neutrophil senescence by microRNAs.

    Directory of Open Access Journals (Sweden)

    Jon R Ward

    2011-01-01

    Full Text Available Neutrophils are rapidly recruited to sites of tissue injury or infection, where they protect against invading pathogens. Neutrophil functions are limited by a process of neutrophil senescence, which renders the cells unable to respond to chemoattractants, carry out respiratory burst, or degranulate. In parallel, aged neutrophils also undergo spontaneous apoptosis, which can be delayed by factors such as GMCSF. This is then followed by their subsequent removal by phagocytic cells such as macrophages, thereby preventing unwanted inflammation and tissue damage. Neutrophils translate mRNA to make new proteins that are important in maintaining functional longevity. We therefore hypothesised that neutrophil functions and lifespan might be regulated by microRNAs expressed within human neutrophils. Total RNA from highly purified neutrophils was prepared and subjected to microarray analysis using the Agilent human miRNA microarray V3. We found human neutrophils expressed a selected repertoire of 148 microRNAs and that 6 of these were significantly upregulated after a period of 4 hours in culture, at a time when the contribution of apoptosis is negligible. A list of predicted targets for these 6 microRNAs was generated from http://mirecords.biolead.org and compared to mRNA species downregulated over time, revealing 83 genes targeted by at least 2 out of the 6 regulated microRNAs. Pathway analysis of genes containing binding sites for these microRNAs identified the following pathways: chemokine and cytokine signalling, Ras pathway, and regulation of the actin cytoskeleton. Our data suggest that microRNAs may play a role in the regulation of neutrophil senescence and further suggest that manipulation of microRNAs might represent an area of future therapeutic interest for the treatment of inflammatory disease.

  13. Pomegranate Bioactive Constituents Suppress Cell Proliferation and Induce Apoptosis in an Experimental Model of Hepatocellular Carcinoma: Role of Wnt/β-Catenin Signaling Pathway

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    Deepak Bhatia

    2013-01-01

    Full Text Available Hepatocellular carcinoma (HCC is the third leading cause of cancer-related death worldwide, and chemoprevention represents a viable approach in lowering the mortality of this disease. Pomegranate fruit, an abundant source of anti-inflammatory phytochemicals, is gaining tremendous attention for its wide-spectrum health benefits. We previously reported that a characterized pomegranate emulsion (PE prevents diethylnitrosamine (DENA-induced rat hepatocarcinogenesis though inhibition of nuclear factor-kappaB (NF-κB. Since NF-κB concurrently induces Wnt/β-catenin signaling implicated in cell proliferation, cell survival, and apoptosis evasion, we examined antiproliferative, apoptosis-inducing and Wnt/β-catenin signaling-modulatory mechanisms of PE during DENA rat hepatocarcinogenesis. PE (1 or 10 g/kg was administered 4 weeks before and 18 weeks following DENA exposure. There was a significant increase in hepatic proliferation (proliferating cell nuclear antigen and alteration in cell cycle progression (cyclin D1 due to DENA treatment, and PE dose dependently reversed these effects. PE substantially induced apoptosis by upregulating proapoptotic protein Bax and downregulating antiapoptotic protein Bcl-2. PE dose dependently reduced hepatic β-catenin and augmented glycogen synthase kinase-3β expression. Our study provides evidence that pomegranate phytochemicals exert chemoprevention of hepatic cancer through antiproliferative and proapoptotic mechanisms by modulating Wnt/β-catenin signaling. PE, thus, targets two interconnected molecular circuits (canonical NF-κB and Wnt/β-catenin pathways to exert chemoprevention of HCC.

  14. Effects of low dose radiation combined with cyclophosphamide on tumor cell apoptosis, cell cycle and proliferation of bone marrow in tumor-bearing mice

    International Nuclear Information System (INIS)

    Yu Hongsheng; Fei Conghe; Shen Fangzhen; Liang Jun

    2004-01-01

    Objective: To study the effect of low dose radiation (LDR) combined with cyclophosphamide on tumor cell apoptosis, cell cycle, and proliferation of bone marrow in mice tumor-bearing mice. Methods: Kunming strain male mice were implanted with S180 sarcoma cells in the left hind leg subcutaneously as an experimental animal model. Five and 8 days after implantation, the mice were given 75 mGy whole-body γ-ray radiation and CTX(300 mg/kg) by intraperitoneal injection 36 hour after LDR. All mice were sacrificed to measure the tumor volume, tumor cell apoptosis, and cell cycle; the proliferation of bone marrow was analyzed by flow cytometry. Results: Tumor growth was significantly slowed down in the treated groups. The apoptosis of tumor cells increased significantly after LDR. The tumor cells were arrested in G 1 phase in CTX and CTX+LDR groups, more significantly in the latter group than in the former group. Concentration of bone marrow cells and proliferation index in CTX + LDR group were higher than those in CTX group, although concentration of bone marrow cells in CTX and CTX+LDR groups were much lower than that in normal mice. Conclusion: Low dose radiation combined with cyclophosphamide causes more significant G 1 -phase arrest than cyclophosphamide alone and enhances anti-tumor effect markedly. At the same time LDR significantly protects hematopoietic function of bone marrow, which is of practical significance as an adjuvant chemotherapy

  15. The long non-coding RNA HOTAIR promotes the proliferation of serous ovarian cancer cells through the regulation of cell cycle arrest and apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Qiu, Jun-jun [Department of Gynecology, Obstetrics and Gynecology Hospital, Fudan University, 419 Fangxie Road, Shanghai 200011 (China); Department of Obstetrics and Gynecology of Shanghai Medical College, Fudan University, 138 Yixueyuan Road, Shanghai 200032 (China); Shanghai Key Laboratory of Female Reproductive Endocrine-Related Diseases, 413 Zhaozhou Road, Shanghai 200011 (China); Wang, Yan [Cancer Institute, Fudan University Shanghai Cancer Center, 270 Dong' an Road, Shanghai 200032 (China); Department of Oncology, Shanghai Medical College, Fudan University, 130 Dong' an Road, Shanghai 200032 (China); Ding, Jing-xin; Jin, Hong-yan [Department of Gynecology, Obstetrics and Gynecology Hospital, Fudan University, 419 Fangxie Road, Shanghai 200011 (China); Department of Obstetrics and Gynecology of Shanghai Medical College, Fudan University, 138 Yixueyuan Road, Shanghai 200032 (China); Shanghai Key Laboratory of Female Reproductive Endocrine-Related Diseases, 413 Zhaozhou Road, Shanghai 200011 (China); Yang, Gong, E-mail: yanggong@fudan.edu.cn [Cancer Institute, Fudan University Shanghai Cancer Center, 270 Dong' an Road, Shanghai 200032 (China); Department of Oncology, Shanghai Medical College, Fudan University, 130 Dong' an Road, Shanghai 200032 (China); Hua, Ke-qin, E-mail: huakeqin@126.com [Department of Gynecology, Obstetrics and Gynecology Hospital, Fudan University, 419 Fangxie Road, Shanghai 200011 (China); Department of Obstetrics and Gynecology of Shanghai Medical College, Fudan University, 138 Yixueyuan Road, Shanghai 200032 (China); Shanghai Key Laboratory of Female Reproductive Endocrine-Related Diseases, 413 Zhaozhou Road, Shanghai 200011 (China)

    2015-05-01

    HOX transcript antisense RNA (HOTAIR) is a well-known long non-coding RNA (lncRNA) whose dysregulation correlates with poor prognosis and malignant progression in many forms of cancer. Here, we investigate the expression pattern, clinical significance, and biological function of HOTAIR in serous ovarian cancer (SOC). Clinically, we found that HOTAIR levels were overexpressed in SOC tissues compared with normal controls and that HOTAIR overexpression was correlated with an advanced FIGO stage and a high histological grade. Multivariate analysis revealed that HOTAIR is an independent prognostic factor for predicting overall survival in SOC patients. We demonstrated that HOTAIR silencing inhibited A2780 and OVCA429 SOC cell proliferation in vitro and that the anti-proliferative effects of HOTAIR silencing also occurred in vivo. Further investigation into the mechanisms responsible for the growth inhibitory effects by HOTAIR silencing revealed that its knockdown resulted in the induction of cell cycle arrest and apoptosis through certain cell cycle-related and apoptosis-related proteins. Together, these results highlight a critical role of HOTAIR in SOC cell proliferation and contribute to a better understanding of the importance of dysregulated lncRNAs in SOC progression. - Highlights: • HOTAIR overexpression correlates with an aggressive tumour phenotype and a poor prognosis in SOC. • HOTAIR promotes SOC cell proliferation both in vitro and in vivo. • The proliferative role of HOTAIR is associated with regulation of the cell cycle and apoptosis.

  16. A human-like senescence-associated secretory phenotype is conserved in mouse cells dependent on physiological oxygen.

    Directory of Open Access Journals (Sweden)

    Jean-Philippe Coppé

    2010-02-01

    Full Text Available Cellular senescence irreversibly arrests cell proliferation in response to oncogenic stimuli. Human cells develop a senescence-associated secretory phenotype (SASP, which increases the secretion of cytokines and other factors that alter the behavior of neighboring cells. We show here that "senescent" mouse fibroblasts, which arrested growth after repeated passage under standard culture conditions (20% oxygen, do not express a human-like SASP, and differ from similarly cultured human cells in other respects. However, when cultured in physiological (3% oxygen and induced to senesce by radiation, mouse cells more closely resemble human cells, including expression of a robust SASP. We describe two new aspects of the human and mouse SASPs. First, cells from both species upregulated the expression and secretion of several matrix metalloproteinases, which comprise a conserved genomic cluster. Second, for both species, the ability to promote the growth of premalignant epithelial cells was due primarily to the conserved SASP factor CXCL-1/KC/GRO-alpha. Further, mouse fibroblasts made senescent in 3%, but not 20%, oxygen promoted epithelial tumorigenesis in mouse xenographs. Our findings underscore critical mouse-human differences in oxygen sensitivity, identify conditions to use mouse cells to model human cellular senescence, and reveal novel conserved features of the SASP.

  17. Epidermal growth factor prevents thallium(I)- and thallium(III)-mediated rat pheochromocytoma (PC12) cell apoptosis.

    Science.gov (United States)

    Pino, María Teresa Luján; Marotte, Clarisa; Verstraeten, Sandra Viviana

    2017-03-01

    We have reported recently that the proliferation of PC12 cells exposed to micromolar concentrations of Tl(I) or Tl(III) has different outcomes, depending on the absence (EGF - cells) or the presence (EGF + cells) of epidermal growth factor (EGF) added to the media. In the current work, we investigated whether EGF supplementation could also modulate the extent of Tl(I)- or Tl(III)-induced cell apoptosis. Tl(I) and Tl(III) (25-100 μM) decreased cell viability in EGF - but not in EGF + cells. In EGF - cells, Tl(I) decreased mitochondrial potential, enhanced H 2 O 2 generation, and activated mitochondrial-dependent apoptosis. In addition, Tl(III) increased nitric oxide production and caused a misbalance between the anti- and pro-apoptotic members of Bcl-2 family. Tl(I) increased ERK1/2, JNK, p38, and p53 phosphorylation in EGF - cells. In these cells, Tl(III) did not affect ERK1/2 and JNK phosphorylation but increased p53 phosphorylation that was related to the promotion of cell senescence. In addition, this cation significantly activated p38 in both EGF - and EGF + cells. The specific inhibition of ERK1/2, JNK, p38, or p53 abolished Tl(I)-mediated EGF - cell apoptosis. Only when p38 activity was inhibited, Tl(III)-mediated apoptosis was prevented in EGF - and EGF + cells. Together, current results indicate that EGF partially prevents the noxious effects of Tl by preventing the sustained activation of MAPKs signaling cascade that lead cells to apoptosis and point to p38 as a key mediator of Tl(III)-induced PC12 cell apoptosis.

  18. The effect of silver nanoparticles (AgNPs) on proliferation and apoptosis of in ovo cultured glioblastoma multiforme (GBM) cells.

    Science.gov (United States)

    Urbańska, Kaja; Pająk, Beata; Orzechowski, Arkadiusz; Sokołowska, Justyna; Grodzik, Marta; Sawosz, Ewa; Szmidt, Maciej; Sysa, Paweł

    2015-01-01

    Recently, it has been shown that silver nanoparticles (AgNPs) provide a unique approach to the treatment of tumors, especially those of neuroepithelial origin. Thus, the aim of this study was to evaluate the impact of AgNPs on proliferation and activation of the intrinsic apoptotic pathway of glioblastoma multiforme (GBM) cells cultured in an in ovo model. Human GBM cells, line U-87, were placed on chicken embryo chorioallantoic membrane. After 8 days, the tumors were divided into three groups: control (non-treated), treated with colloidal AgNPs (40 μg/ml), and placebo (tumors supplemented with vehicle only). At the end of the experiment, all tumors were isolated. Assessment of cell proliferation and cell apoptosis was estimated by histological, immunohistochemical, and Western blot analyses. The results show that AgNPs can influence GBM growth. AgNPs inhibit proliferation of GBM cells and seem to have proapoptotic properties. Although there were statistically significant differences between control and AgNP groups in the AI and the levels of active caspase 9 and active caspase 3, the level of these proteins in GBM cells treated with AgNPs seems to be on the border between the spontaneous apoptosis and the induced. Our results indicate that the antiproliferative properties of silver nanoparticles overwhelm proapoptotic ones. Further research focused on the cytotoxic effect of AgNPs on tumor and normal cells should be conducted.

  19. Mitotic Stress Is an Integral Part of the Oncogene-Induced Senescence Program that Promotes Multinucleation and Cell Cycle Arrest

    Directory of Open Access Journals (Sweden)

    Dina Dikovskaya

    2015-09-01

    Full Text Available Oncogene-induced senescence (OIS is a tumor suppression mechanism that blocks cell proliferation in response to oncogenic signaling. OIS is frequently accompanied by multinucleation; however, the origin of this is unknown. Here, we show that multinucleate OIS cells originate mostly from failed mitosis. Prior to senescence, mutant H-RasV12 activation in primary human fibroblasts compromised mitosis, concordant with abnormal expression of mitotic genes functionally linked to the observed mitotic spindle and chromatin defects. Simultaneously, H-RasV12 activation enhanced survival of cells with damaged mitoses, culminating in extended mitotic arrest and aberrant exit from mitosis via mitotic slippage. ERK-dependent transcriptional upregulation of Mcl1 was, at least in part, responsible for enhanced survival and slippage of cells with mitotic defects. Importantly, mitotic slippage and oncogene signaling cooperatively induced senescence and key senescence effectors p21 and p16. In summary, activated Ras coordinately triggers mitotic disruption and enhanced cell survival to promote formation of multinucleate senescent cells.

  20. Ageing induced vascular smooth muscle cell senescence in atherosclerosis.

    Science.gov (United States)

    Uryga, Anna K; Bennett, Martin R

    2016-04-15

    Atherosclerosis is a disease of ageing in that its incidence and prevalence increase with age. However, atherosclerosis is also associated with biological ageing, manifest by a number of typical hallmarks of ageing in the atherosclerotic plaque. Thus, accelerated biological ageing may be superimposed on the effects of chronological ageing in atherosclerosis. Tissue ageing is seen in all cells that comprise the plaque, but particularly in vascular smooth muscle cells (VSMCs). Hallmarks of ageing include evidence of cell senescence, DNA damage (including telomere attrition), mitochondrial dysfunction, a pro-inflammatory secretory phenotype, defects in proteostasis, epigenetic changes, deregulated nutrient sensing, and exhaustion of progenitor cells. In this model, initial damage to DNA (genomic, telomeric, mitochondrial and epigenetic changes) results in a number of cellular responses (cellular senescence, deregulated nutrient sensing and defects in proteostasis). Ultimately, ongoing damage and attempts at repair by continued proliferation overwhelm reparative capacity, causing loss of specialised cell functions, cell death and inflammation. This review summarises the evidence for accelerated biological ageing in atherosclerosis, the functional consequences of cell ageing on cells comprising the plaque, and the causal role that VSMC senescence plays in atherogenesis. © 2015 The Authors. The Journal of Physiology © 2015 The Physiological Society.

  1. Silencing of Tumor Necrosis Factor Receptor 1 by siRNA in EC109 Cells Affects Cell Proliferation and Apoptosis

    Directory of Open Access Journals (Sweden)

    Ma Changhui

    2009-01-01

    Full Text Available Tumor necrosis factor receptor 1 (TNFR1 is a membrane receptor able to bind TNF-α or TNF-β. TNFR1 can suppress apoptosis by activating the NF-κB or JNK/SAPK signal transduction pathway, or it can induce apoptosis through a series of caspase cascade reactions; the particular effect may depend on the cell line. In the present study, we first showed that TNFR1 is expressed at both the gene and protein levels in the esophageal carcinoma cell line EC109. Then, by applying a specific siRNA, we silenced the expression of TNFR1; this resulted in a significant time-dependent promotion of cell proliferation and downregulation of the apoptotic rate. These results suggest that TNFR1 is strongly expressed in the EC109 cell line and that it may play an apoptosis-mediating role, which may be suppressed by highly activated NF-κB.

  2. Pomegranate exerts chemoprevention of experimentally induced mammary tumorigenesis by suppression of cell proliferation and induction of apoptosis.

    Science.gov (United States)

    Bishayee, Anupam; Mandal, Animesh; Bhattacharyya, Piyali; Bhatia, Deepak

    2016-01-01

    Breast cancer is the second leading cause of cancer-related death in women in the United States and discovery and development of safe chemopreventive drugs is urgently needed. The fruit pomegranate (Punica granatum) is gaining importance because of its various health benefits. This study was initiated to investigate chemopreventive potential of a pomegranate emulsion (PE) against 7,12-dimethylbenz(a)anthracene (DMBA) rat mammary carcinogenesis. The animals were orally administered with PE (0.2-5.0 g/kg), starting 2 wk before and 16 wk following DMBA treatment. PE exhibited a striking reduction of DMBA-induced mammary tumor incidence, total tumor burden, and reversed histopathological changes. PE dose-dependently suppressed cell proliferation and induced apoptosis in mammary tumors. Immunohistochemical studies showed that PE increased intratumor Bax, decreased Bcl2 and manifested a proapoptotic shift in Bax/Bcl2 ratio. In addition, our gene expression study showed PE-mediated upregulation of Bad, caspase-3, caspase-7, caspase-9, poly (ADP ribose) polymerase and cytochrome c in mammary tumors. Thus, PE exerts chemoprevention of mammary carcinogenesis by suppressing cell proliferation and inducing apoptosis mediated through upregulation of Bax and downregulation of Bcl2 in concert with caspase cascades. Pomegranate bioactive phytoconstituents could be developed as a chemopreventive drug to reduce the risk of breast cancer.

  3. Rejuvenation of MPTP-induced human neural precursor cell senescence by activating autophagy

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Liang [East Hospital, Tongji University School of Medicine, Shanghai (China); Dong, Chuanming [East Hospital, Tongji University School of Medicine, Shanghai (China); Department of Anatomy and Neurobiology, The Jiangsu Key Laboratory of Neuroregeneration, Nantong University, Nantong (China); Sun, Chenxi; Ma, Rongjie; Yang, Danjing [East Hospital, Tongji University School of Medicine, Shanghai (China); Zhu, Hongwen, E-mail: hongwen_zhu@hotmail.com [Tianjin Hospital, Tianjin Academy of Integrative Medicine, Tianjin (China); Xu, Jun, E-mail: xunymc2000@yahoo.com [East Hospital, Tongji University School of Medicine, Shanghai (China)

    2015-08-21

    Aging of neural stem cell, which can affect brain homeostasis, may be caused by many cellular mechanisms. Autophagy dysfunction was found in aged and neurodegenerative brains. However, little is known about the relationship between autophagy and human neural stem cell (hNSC) aging. The present study used 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP) to treat neural precursor cells (NPCs) derived from human embryonic stem cell (hESC) line H9 and investigate related molecular mechanisms involved in this process. MPTP-treated NPCs were found to undergo premature senescence [determined by increased senescence-associated-β-galactosidase (SA-β-gal) activity, elevated intracellular reactive oxygen species level, and decreased proliferation] and were associated with impaired autophagy. Additionally, the cellular senescence phenotypes were manifested at the molecular level by a significant increase in p21 and p53 expression, a decrease in SOD2 expression, and a decrease in expression of some key autophagy-related genes such as Atg5, Atg7, Atg12, and Beclin 1. Furthermore, we found that the senescence-like phenotype of MPTP-treated hNPCs was rejuvenated through treatment with a well-known autophagy enhancer rapamycin, which was blocked by suppression of essential autophagy gene Beclin 1. Taken together, these findings reveal the critical role of autophagy in the process of hNSC aging, and this process can be reversed by activating autophagy. - Highlights: • We successfully establish hESC-derived neural precursor cells. • MPTP treatment induced senescence-like state in hESC-derived NPCs. • MPTP treatment induced impaired autophagy of hESC-derived NPCs. • MPTP-induced hESC-derived NPC senescence was rejuvenated by activating autophagy.

  4. Identification of apoptosis-related PLZF target genes

    International Nuclear Information System (INIS)

    Bernardo, Maria Victoria; Yelo, Estefania; Gimeno, Lourdes; Campillo, Jose Antonio; Parrado, Antonio

    2007-01-01

    The PLZF gene encodes a BTB/POZ-zinc finger-type transcription factor, involved in physiological development, proliferation, differentiation, and apoptosis. In this paper, we investigate proliferation, survival, and gene expression regulation in stable clones from the human haematopoietic K562, DG75, and Jurkat cell lines with inducible expression of PLZF. In Jurkat cells, but not in K562 and DG75 cells, PLZF induced growth suppression and apoptosis in a cell density-dependent manner. Deletion of the BTB/POZ domain of PLZF abrogated growth suppression and apoptosis. PLZF was expressed with a nuclear speckled pattern distinctively in the full-length PLZF-expressing Jurkat clones, suggesting that the nuclear speckled localization is required for PLZF-induced apoptosis. By microarray analysis, we identified that the apoptosis-inducer TP53INP1, ID1, and ID3 genes were upregulated, and the apoptosis-inhibitor TERT gene was downregulated. The identification of apoptosis-related PLZF target genes may have biological and clinical relevance in cancer typified by altered PLZF expression

  5. Water extract of Semecarpus parvifolia Thw. leaves inhibits cell proliferation and induces apoptosis on HEp-2 cells.

    Science.gov (United States)

    Soysa, Preethi; Jayarthne, Panchima; Ranathunga, Imali

    2018-03-05

    Semecarpus parvifolia Thw is used as an ingredient of poly herbal decoctions to treat cancer in traditional medicine. The present study aims to investigate the antiproliferative activity on HEp 2 cells by the water extract of S. parvifolia leaves and to evaluate potential mechanisms. The plant extract was exposed to S. parvifolia for 24 hours and antiproliferative activity was quantified by Sulforhodamine B (SRB), 3-(4, 5-dimethythiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) and Lactate dehydrogenase (LDH) assays. Morphological changes were observed after staining cells with ethidium bromide/acridine orange (EB/AO) and Giemsa dye. Comet assay was performed to evaluate the DNA damage. The toxicity of the plant extract was determined by brine shrimp lethality assay. S. parvifolia leaves reduced the cell proliferation in a dose and time dependent manner. A two fold increase in NO level was observed at higher concentrations. Morphological changes characteristic to apoptosis were observed in light microscopy, Giemsa and EB/AO stained cells. Fragmented DNA further confirmed its capacity to induce apoptosis. No lethality was observed with brine shrimps. The results suggest that Semecarpus parvifolia Thw induces apoptosis in HEp-2 cells through a NO dependent pathway.

  6. Resveratrol suppresses IGF-1 induced human colon cancer cell proliferation and elevates apoptosis via suppression of IGF-1R/Wnt and activation of p53 signaling pathways

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    Radhakrishnan Sridhar

    2010-05-01

    Full Text Available Abstract Background Obesity is a global phenomenon and is associated with various types of cancer, including colon cancer. There is a growing interest for safe and effective bioactive compounds that suppress the risk for obesity-promoted colon cancer. Resveratrol (trans-3, 4', 5,-trihydroxystilbene, a stilbenoid found in the skin of red grapes and peanuts suppresses many types of cancers by regulating cell proliferation and apoptosis through a variety of mechanisms, however, resveratrol effects on obesity-promoted colon cancer are not clearly established. Methods We investigated the anti-proliferative effects of resveratrol on HT-29 and SW480 human colon cancer cells in the presence and absence of insulin like growth factor-1 (IGF-1; elevated during obesity and elucidated the mechanisms of action using IGF-1R siRNA in HT-29 cells which represents advanced colon carcinogenesis. Results Resveratrol (100-150 μM exhibited anti-proliferative properties in HT-29 cells even after IGF-1 exposure by arresting G0/G1-S phase cell cycle progression through p27 stimulation and cyclin D1 suppression. Treatment with resveratrol suppressed IGF-1R protein levels and concurrently attenuated the downstream Akt/Wnt signaling pathways that play a critical role in cell proliferation. Targeted suppression of IGF-1R using IGF-1R siRNA also affected these signaling pathways in a similar manner. Resveratrol treatment induced apoptosis by activating tumor suppressor p53 protein, whereas IGF-1R siRNA treatment did not affect apoptosis. Our data suggests that resveratrol not only suppresses cell proliferation by inhibiting IGF-1R and its downstream signaling pathways similar to that of IGF-1R siRNA but also enhances apoptosis via activation of the p53 pathway. Conclusions For the first time, we report that resveratrol suppresses colon cancer cell proliferation and elevates apoptosis even in the presence of IGF-1 via suppression of IGF-1R/Akt/Wnt signaling pathways and

  7. Resveratrol suppresses IGF-1 induced human colon cancer cell proliferation and elevates apoptosis via suppression of IGF-1R/Wnt and activation of p53 signaling pathways

    International Nuclear Information System (INIS)

    Vanamala, Jairam; Reddivari, Lavanya; Radhakrishnan, Sridhar; Tarver, Chris

    2010-01-01

    Obesity is a global phenomenon and is associated with various types of cancer, including colon cancer. There is a growing interest for safe and effective bioactive compounds that suppress the risk for obesity-promoted colon cancer. Resveratrol (trans-3, 4', 5,-trihydroxystilbene), a stilbenoid found in the skin of red grapes and peanuts suppresses many types of cancers by regulating cell proliferation and apoptosis through a variety of mechanisms, however, resveratrol effects on obesity-promoted colon cancer are not clearly established. We investigated the anti-proliferative effects of resveratrol on HT-29 and SW480 human colon cancer cells in the presence and absence of insulin like growth factor-1 (IGF-1; elevated during obesity) and elucidated the mechanisms of action using IGF-1R siRNA in HT-29 cells which represents advanced colon carcinogenesis. Resveratrol (100-150 μM) exhibited anti-proliferative properties in HT-29 cells even after IGF-1 exposure by arresting G 0 /G 1 -S phase cell cycle progression through p27 stimulation and cyclin D1 suppression. Treatment with resveratrol suppressed IGF-1R protein levels and concurrently attenuated the downstream Akt/Wnt signaling pathways that play a critical role in cell proliferation. Targeted suppression of IGF-1R using IGF-1R siRNA also affected these signaling pathways in a similar manner. Resveratrol treatment induced apoptosis by activating tumor suppressor p53 protein, whereas IGF-1R siRNA treatment did not affect apoptosis. Our data suggests that resveratrol not only suppresses cell proliferation by inhibiting IGF-1R and its downstream signaling pathways similar to that of IGF-1R siRNA but also enhances apoptosis via activation of the p53 pathway. For the first time, we report that resveratrol suppresses colon cancer cell proliferation and elevates apoptosis even in the presence of IGF-1 via suppression of IGF-1R/Akt/Wnt signaling pathways and activation of p53, suggesting its potential role as a

  8. Histomorfometria, apoptose e proliferação celular em neoplasias intraepiteliais do colo uterino Histomorphometry, apoptosis and cell proliferation in cervical intraepithelial neoplasia

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    Rodrigo Tadeu de Puy e Souza

    2011-12-01

    alterations. Accumulation of such mutations and unbalance of genomic homeostasis induce changes in certain genes as well as affect cell proliferation and apoptosis. Immunohistochemical markers of cellular proliferation, apoptosis and cell survival in cervical intraepithelial lesions still require morphometric studies in order to define their role in the development of dysplasias caused by invasive carcinoma. OBJECTIVES: In order to better understand the processes of cellular proliferation, apoptosis and epithelial turn over in such precursory lesions, histomorphometric evaluation for mitosis and apoptosis as well as immunohistochemical reactions for Bax, Bcl-2 and Ki-67 proteins (reactivity, localization and intensity were carried out in cervical biopsies. METHODS: Samples were split into four groups: 1. cervicitis (n = 20; 2. light dysplasia (n = 20; 3. moderate dysplasia (n = 20; 4. severe dysplasia (n = 20. RESULTS: Intense proliferation and apoptosis were observed in lesions with high, extensive, intense, and diffuse Ki-67 and Bax immunolabeling. Proliferation and apoptosis were mild or null in groups 1 and 2. Bcl-2 immunolabeling was more intense in high degree lesions and mild in the other groups. Extensive Ki-67 and Bax immunolabeling suggests an increased cellular turn over, which was also corroborated by histomorphometry. The more severe the dysplasia is the higher Bcl-2 expression. CONCLUSION: These data indicate that the pre-neoplastic process is dynamic and is concomitant with apoptosis and mitosis.

  9. miR-139-5p regulates proliferation, apoptosis, and cell cycle of uterine leiomyoma cells by targeting TPD52

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    Chen H

    2016-10-01

    Full Text Available Hong Chen,1 Hong Xu,1 Yu-gang Meng,1 Yun Zhang,2 Jun-ying Chen,1 Xiao-ning Wei1 1Department of Gynaecology, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, 2Department of Gynaecology, The People’s Hospital of Suzhou High Tech District, Suzhou, Jiangsu, People’s Republic of China Background: Uterine leiomyoma is one of the most common benign tumors in women. It dramatically decreases the quality of life in the affected women. However, there is a lack of effective treatment paradigms. Micro-RNAs are small noncoding RNA molecules that are extensively expressed in organisms, and they are interrelated with the occurrence and development of the tumor. miR-139-5p was found to be downregulated in various cancers, but its function and mechanism in uterine leiomyoma remain unknown. The aim of this study was to investigate the role of miR-139-5p and its target gene in uterine leiomyoma.Methods: By using a bioinformatic assay, it was found that TPD52 was a potential target gene of miR-139-5p. Then, expressions of miR-139-5p and TPD52 in uterine leiomyoma and adjacent myometrium tissues were evaluated by quantitative real-time polymerase chain reaction and Western blot. Proliferation, apoptosis, and cell cycle of uterine leiomyoma cells transfected by miR-139-5p mimics or TPD52 siRNA were determined.Results: It was observed that the expression of miR-139-5p in uterine leiomyoma tissues was significantly lower (P<0.001 than that in the adjacent myometrium tissues. Overexpression of miR-139-5p inhibited the growth of uterine leiomyoma cells and induced apoptosis and G1 phase arrest. Dual-luciferase reporter assay and Western blot validated that TPD52 is the target gene of miR-139-5p. Furthermore, downregulation of TPD52 by siRNA in uterine leiomyoma cells inhibited cell proliferation and induced cell apoptosis and G1 phase arrest.Conclusion: Data suggested that miR-139-5p inhibited the proliferation of uterine leiomyoma cells

  10. Effect of Ovarian Steroids on Colonic Epithelial Cell Proliferation and Apoptosis in Rats

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    K. Altunbas

    2007-01-01

    Full Text Available The aim of this study was to investigate the effects of steroid hormones on proliferation and apoptosis in the colon crypt epithelium. The research was conducted on adult ovariectomized (Ovx rats (Sprague Dawley. Ovx rats were injected for 15 days with 0.2 ml of sesame oil (control; C, or 17β-oestradiol (10 μg/d; E, or progesterone (2 mg/d; P, or E + P. Proliferative activity in the colon was assessed by using proliferating cell nuclear antigen (PCNA antibody. The proliferation index (PI, the number of PCNA positive cells divided by the total number of cells counted in the crypt column multiplied by 100, was calculated. PI was lower in the hormonetreated groups, especially in group P compared to that in group C. The apoptotic index (AI, the mean number of apoptotic cells, was detected by active caspase 3 immunoreactivity per crypt in the colon. AI was lower in the colon crypt epithelium of group E than that of the other groups. However, AI in the colon crypt epithelium in groups P and E + P was higher than that of both group E and group C. In addition, the colon crypt size (the number of epithelial cells lining one side of 10 well-oriented, longitudinally cut crypts was considerably lower in group E than that of the other groups. In conclusion, we showed that the decrease of AI in group E was balanced by progesterone; the decrease of PI in group P was also depressed by oestrogen.

  11. Radiation-induced senescence-like phenotype in proliferating and plateau-phase vascular endothelial cells

    International Nuclear Information System (INIS)

    Igarashi, Kaori; Sakimoto, Ippei; Kataoka, Keiko; Ohta, Keisuke; Miura, Masahiko

    2007-01-01

    The effects of ionizing radiation (IR) on tumor angiogenesis still remain largely unknown. In this study, we found that IR (8 Gy) induces a high-frequency (80-90%) senescence-like phenotype in vascular endothelial cells (ECs) undergoing exponential growth. This finding allowed us to characterize the IR-induced senescence-like (IRSL) phenotype by examining the gene expression profiles and in vitro angiogenic activities of these ECs. The expression levels of genes associated with cell cycle progression and DNA replication were remarkably reduced in the IRSL ECs. Additionally, the in vitro invasion and migration activities of these cells through Matrigel were significantly suppressed. We also found that confluent ECs exhibited a high-frequency IRSL phenotype when they were replated immediately after irradiation, whereas incubation in plateau-phase conditions reduced the induction of this phenotype and enhanced colony formation. The kinetics of DNA double-strand break repair, which showed a faster time course in confluent ECs than in growing ECs, may contribute to the protective mechanism associated with the IRSL phenotype. These results imply that the IRSL phenotype may be important for determining the angiogenic activity of ECs following irradiation. The present study should contribute to the understanding of the effects of IR on tumor angiogenesis

  12. Disappearance of the telomere dysfunction-induced stress response in fully senescent cells.

    Science.gov (United States)

    Bakkenist, Christopher J; Drissi, Rachid; Wu, Jing; Kastan, Michael B; Dome, Jeffrey S

    2004-06-01

    Replicative senescence is a natural barrier to cellular proliferation that is triggered by telomere erosion and dysfunction. Here, we demonstrate that ATM activation and H2AX-gamma nuclear focus formation are sensitive markers of telomere dysfunction in primary human fibroblasts. Whereas the activated form of ATM and H2AX-gamma foci were rarely observed in early-passage cells, they were readily detected in late-passage cells. The ectopic expression of telomerase in late-passage cells abrogated ATM activation and H2AX-gamma focus formation, suggesting that these stress responses were the consequence of telomere dysfunction. ATM activation was induced in quiescent fibroblasts by inhibition of TRF2 binding to telomeres, indicating that telomere uncapping is sufficient to initiate the telomere signaling response; breakage of chromosomes with telomeric associations is not required for this activation. Although ATM activation and H2AX-gamma foci were readily observed in late-passage cells, they disappeared once cells became fully senescent, indicating that constitutive signaling from dysfunctional telomeres is not required for the maintenance of senescence.

  13. Equine Metabolic Syndrome Affects Viability, Senescence, and Stress Factors of Equine Adipose-Derived Mesenchymal Stromal Stem Cells: New Insight into EqASCs Isolated from EMS Horses in the Context of Their Aging

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    Krzysztof Marycz

    2016-01-01

    Full Text Available Currently, equine metabolic syndrome (EMS, an endocrine disease linked to insulin resistance, affects an increasing number of horses. However, little is known about the effect of EMS on mesenchymal stem cells that reside in adipose tissue (ASC. Thus it is crucial to evaluate the viability and growth kinetics of these cells, particularly in terms of their application in regenerative medicine. In this study, we investigated the proliferative capacity, morphological features, and accumulation of oxidative stress factors in mesenchymal stem cells isolated from healthy animals (ASCN and horses suffering from EMS (ASCEMS. ASCEMS displayed senescent phenotype associated with β-galactosidase accumulation, enlarged cell bodies and nuclei, increased apoptosis, and reduced heterochromatin architecture. Moreover, we observed increased amounts of nitric oxide (NO and reactive oxygen species (ROS in these cells, accompanied by reduced superoxide dismutase (SOD activity. We also found in ASCEMS an elevated number of impaired mitochondria, characterized by membrane raptures, disarrayed cristae, and vacuole formation. Our results suggest that the toxic compounds, accumulating in the mitochondria under oxidative stress, lead to alternations in their morphology and may be partially responsible for the senescent phenotype and decreased proliferation potential of ASCEMS.

  14. The p53-reactivating small molecule RITA induces senescence in head and neck cancer cells.

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    Hui-Ching Chuang

    Full Text Available TP53 is the most commonly mutated gene in head and neck cancer (HNSCC, with mutations being associated with resistance to conventional therapy. Restoring normal p53 function has previously been investigated via the use of RITA (reactivation of p53 and induction of tumor cell apoptosis, a small molecule that induces a conformational change in p53, leading to activation of its downstream targets. In the current study we found that RITA indeed exerts significant effects in HNSCC cells. However, in this model, we found that a significant outcome of RITA treatment was accelerated senescence. RITA-induced senescence in a variety of p53 backgrounds, including p53 null cells. Also, inhibition of p53 expression did not appear to significantly inhibit RITA-induced senescence. Thus, this phenomenon appears to be partially p53-independent. Additionally, RITA-induced senescence appears to be partially mediated by activation of the DNA damage response and SIRT1 (Silent information regulator T1 inhibition, with a synergistic effect seen by combining either ionizing radiation or SIRT1 inhibition with RITA treatment. These data point toward a novel mechanism of RITA function as well as hint to its possible therapeutic benefit in HNSCC.

  15. Effects of microRNA-129 and its target gene c-Fos on proliferation and apoptosis of hippocampal neurons in rats with epilepsy via the MAPK signaling pathway.

    Science.gov (United States)

    Wu, Dong-Mei; Zhang, Yu-Tong; Lu, Jun; Zheng, Yuan-Lin

    2018-09-01

    This study aims to investigate the effect of microRNA-129 (miR-129) on proliferation and apoptosis of hippocampal neurons in epilepsy rats by targeting c-Fos via the MAPK signaling pathway. Thirty rats were equally classified into a model group (successfully established as chronic epilepsy models) and a normal group. Expression of miR-129, c-Fos, bax, and MAPK was detected by RT-qPCR and Western blotting. Hippocampal neurons were assigned into normal, blank, negative control (NC), miR-129 mimic, miR-129 inhibitor, siRNA-c-Fos, miR-129 inhibitor+siRNA-c-Fos groups. The targeting relationship between miR-129 and c-Fos was predicted and verified by bioinformatics websites and dual-luciferase reporter gene assay. Cell proliferation after transfection was measured by MTT assay, and cell cycle and apoptosis by flow cytometry. c-Fos is a potential target gene of miR-129. Compared with the normal group, the other six groups showed a decreased miR-129 expression; increased expression of expression of c-Fos, Bax, and MAPK; decreased proliferation; accelerated apoptosis; more cells arrested in the G1 phase; and fewer cells arrested in the S phase. Compared with the blank and NC groups, the miR-129 mimic group and the siRNA-c-Fos group showed decreased expression of c-Fos, Bax, and MAPK, increased cells proliferation, and decreased cell apoptosis, fewer cells arrested in the G1 phase and more cells arrested in the S phase. However, the miR-129 inhibitor groups showed reverse consequences. This study suggests that miR-129 could inhibit the occurrence and development of epilepsy by repressing c-Fos expression through inhibiting the MAPK signaling pathway. © 2017 Wiley Periodicals, Inc.

  16. Effects of oridonin nanosuspension on cell proliferation and apoptosis of human prostatic carcinoma PC-3 cell line

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    Zhen Zhang

    2010-10-01

    Full Text Available Zhen Zhang, Xiumei Zhang, Wei Xue, Yuna YangYang, Derong Xu, Yunxue Zhao, Haiyan LouSchool of Medicine, Shandong University, Jinan, Republic of ChinaAbstract: This study aims to investigate the inhibitory effects of oridonin nanosuspension on human prostatic carcinoma PC-3 cell line in vitro. The PC-3 cells were incubated with increasing concentrations of oridonin solution and nanosuspensions for 12 hours, 24 hours, and 36 hours. MTT [3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide] assay was performed to measure cellular viability and investigate the effect of oridonin on cell growth of PC-3. Annexin V-FITC/PI staining method was used to determine the effect of oridonin by fluorescence microscope and flow cytometry, respectively. Nanosuspension on early apoptosis of PC-3 cells was also evaluated. Oridonin significantly inhibited the growth of PC-3 cells after 12 hours, 24 hours, and 36 hours of treatment in a dose-dependent manner (P < 0.05. Compared with the same concentration of oridonin solution, oridonin nanosuspension enhanced the inhibition ratio of proliferation. The observation of propidium iodide fluorescence staining confirmed the MTT assay results. The cell proportion of PC-3 at the G2/M phase in the nanosuspension treatment group was upregulated compared with that of the control and oridonin solution groups. Both oridonin solution and nanosuspension promoted the early apoptosis of PC-3 cells. Furthermore, while improving the ratio of early apoptosis, oridonin nanosuspensions also enhanced growth suppression, and induced apoptosis of PC-3 cells. This shows great potential in the treatment of androgen-independent carcinoma of prostate by oridonin nanosuspensions.Keywords: oridonin, nanosuspension, carcinoma of prostate, PC-3 cells, cell cycle, apoptosis

  17. A crucial role of ROCK for alleviation of senescence-associated phenotype.

    Science.gov (United States)

    Park, Joon Tae; Kang, Hyun Tae; Park, Chi Hyun; Lee, Young-Sam; Cho, Kyung A; Park, Sang Chul

    2018-06-01

    In our previous study, we uncovered a novel mechanism in which amelioration of Hutchinson-Gilford progeria syndrome (HGPS) phenotype is mediated by mitochondrial functional recovery upon rho-associated protein kinase (ROCK) inhibition. However, it remains elusive whether this mechanism is also applied to the amelioration of normal aging cells. In this study, we used Y-27632 and fasudil as effective ROCK inhibitors, and examined their role in senescence. We found that ROCK inhibition induced the functional recovery of the mitochondria as well as the metabolic reprogramming, which are two salient features that are altered in normal aging cells. Moreover, microarray analysis revealed that the up-regulated pathway upon ROCK inhibition is enriched for chromatin remodeling genes, which may play an important role in the alleviation of senescence-associated cell cycle arrest. Indeed, ROCK inhibition induced cellular proliferation, concomitant with the amelioration of senescent phenotype. Furthermore, the restorative effect by ROCK inhibition was observed in vivo as evidenced by the facilitated cutaneous wound healing. Taken together, our data indicate that ROCK inhibition might be utilized to ameliorate normal aging process and to treat age-related disease. Copyright © 2018 Elsevier Inc. All rights reserved.

  18. Selective insulin resistance in hepatocyte senescence

    International Nuclear Information System (INIS)

    Aravinthan, Aloysious; Challis, Benjamin; Shannon, Nicholas; Hoare, Matthew; Heaney, Judith; Alexander, Graeme J.M.

    2015-01-01

    Insulin resistance has been described in association with chronic liver disease for decades. Hepatocyte senescence has been demonstrated in chronic liver disease and as many as 80% of hepatocytes show a senescent phenotype in advanced liver disease. The aim of this study was to understand the role of hepatocyte senescence in the development of insulin resistance. Senescence was induced in HepG2 cells via oxidative stress. The insulin metabolic pathway was studied in control and senescent cells following insulin stimulation. GLUT2 and GLUT4 expressions were studied in HepG2 cells and human liver tissue. Further, GLUT2 and GLUT4 expressions were studied in three independent chronic liver disease cohorts. Signalling impairment distal to Akt in phosphorylation of AS160 and FoxO1 was evident in senescent HepG2 cells. Persistent nuclear localisation of FoxO1 was demonstrated in senescent cells despite insulin stimulation. Increased GLUT4 and decreased GLUT2 expressions were evident in senescent cells, human cirrhotic liver tissue and publically available liver disease datasets. Changes in GLUT expressions were associated with a poor clinical prognosis. In conclusion, selective insulin resistance is evident in senescent HepG2 cells and changes in GLUT expressions can be used as surrogate markers of hepatocyte senescence. - Highlights: • Senescent hepatocytes demonstrate selective insulin resistance. • GLUT changes act as markers of hepatocyte senescence and have prognostic value. • Study offers insight into long noticed intimacy of cirrhosis and insulin resistance

  19. Selective insulin resistance in hepatocyte senescence

    Energy Technology Data Exchange (ETDEWEB)

    Aravinthan, Aloysious [Division of Gastroenterology and Hepatology, Department of Medicine, University of Cambridge, Cambridge (United Kingdom); Challis, Benjamin [Institute of Metabolic Sciences, University of Cambridge, Cambridge (United Kingdom); Shannon, Nicholas [Cancer Research UK Cambridge Institute, Cambridge (United Kingdom); Hoare, Matthew [Division of Gastroenterology and Hepatology, Department of Medicine, University of Cambridge, Cambridge (United Kingdom); Cancer Research UK Cambridge Institute, Cambridge (United Kingdom); Heaney, Judith [Division of Gastroenterology and Hepatology, Department of Medicine, University of Cambridge, Cambridge (United Kingdom); Foundation for Liver Research, Institute of Hepatology, London (United Kingdom); Alexander, Graeme J.M., E-mail: gja1000@doctors.org.uk [Division of Gastroenterology and Hepatology, Department of Medicine, University of Cambridge, Cambridge (United Kingdom)

    2015-02-01

    Insulin resistance has been described in association with chronic liver disease for decades. Hepatocyte senescence has been demonstrated in chronic liver disease and as many as 80% of hepatocytes show a senescent phenotype in advanced liver disease. The aim of this study was to understand the role of hepatocyte senescence in the development of insulin resistance. Senescence was induced in HepG2 cells via oxidative stress. The insulin metabolic pathway was studied in control and senescent cells following insulin stimulation. GLUT2 and GLUT4 expressions were studied in HepG2 cells and human liver tissue. Further, GLUT2 and GLUT4 expressions were studied in three independent chronic liver disease cohorts. Signalling impairment distal to Akt in phosphorylation of AS160 and FoxO1 was evident in senescent HepG2 cells. Persistent nuclear localisation of FoxO1 was demonstrated in senescent cells despite insulin stimulation. Increased GLUT4 and decreased GLUT2 expressions were evident in senescent cells, human cirrhotic liver tissue and publically available liver disease datasets. Changes in GLUT expressions were associated with a poor clinical prognosis. In conclusion, selective insulin resistance is evident in senescent HepG2 cells and changes in GLUT expressions can be used as surrogate markers of hepatocyte senescence. - Highlights: • Senescent hepatocytes demonstrate selective insulin resistance. • GLUT changes act as markers of hepatocyte senescence and have prognostic value. • Study offers insight into long noticed intimacy of cirrhosis and insulin resistance.

  20. IL13Rα2 siRNA inhibited cell proliferation, induced cell apoptosis, and suppressed cell invasion in papillary thyroid carcinoma cells

    Directory of Open Access Journals (Sweden)

    Gu MJ

    2018-03-01

    Full Text Available Mingjun Gu Department of Endocrinology, Shanghai Gongli Hospital, The Second Military Medical University, Shanghai, People’s Republic of China Aim: Papillary thyroid carcinoma (PTC is the most common type of thyroid cancer. Infiltrative growth and metastasis are the two most intractable characteristics of PTC. Interleukin-13 receptor α2 (IL13Rα2 with high affinity for Th2-derived cytokine IL-13 has been reported to be overexpressed in several tumors. In this study, an analysis of IL13Rα2 expression in PTC and matched paracancerous tissues was undertaken, and its biologic functions in PTC were assessed. Methods: IL13Rα2 and vascular endothelial growth factor (VEGF expression were detected by using real-time polymerase chain reaction and immunohistochemistry analyses. Cell proliferation, invasion, apoptosis, and caspase activity were measured with the Cell Counting Kit-8, Transwell, flow cytometry analyses, and biochemistry assay, respectively. Results: Upregulation of IL13Rα2 and VEGF was observed in PTC tissues compared with matched paracancerous tissues. Pearson’s correlation analysis indicated that IL13Rα2 mRNA level in the tested PTC tissues was positively correlated with VEGF mRNA level. Besides, inhibited cell proliferation, induced cell apoptosis, and suppressed cell invasion were detected in IL13Rα2-silenced TPC-1 cells. Increased activity of Caspase 3 and Caspase 9, along with elevated cleaved Caspase 3 and poly (ADP-ribose polymerase indicated the signal pathway of cell apoptosis induced by IL13Rα2 siRNA. In addition, downregulated metastasis- and angiogenesis-related proteins VEGF, VEGFR2, MMP2, and MMP9 indicated the decreased number of invading cells after knockdown of IL13Rα2. Conclusion: The results demonstrate that IL13Rα2 plays an important role in the progress of PTC. IL13Rα2 knockdown in PTC cells inhibited cell proliferation, induced cell apoptosis, and suppressed cell invasion. These data suggest that IL13Rα2

  1. [Study on thaspine in inducing apoptosis of A549 cell].

    Science.gov (United States)

    Zhang, Yan-min; He, Lang-chong

    2007-04-01

    To investigate the effect of thaspine on the cellular proliferation, apoptosis and cell cycle in A549 cell line. A549 cell was cultured with different concentrations of thaspine. Cellular proliferation was detected with MTT, apoptosis and cell cycle were checked with Flow Cytometer, and change of microstructure was observed by transmission electron microscope. Thaspine could inhibit the proliferation and induce apoptosis of A549 cell in a time-dose dependent manner. Cell cycle was significantly stopped at the S phase by thaspine with FCM technology. Under electronic microscope, the morphology of A549 cell showed nuclear karyopycnosis, chromatin agglutination and typical apoptotic body when the cell was treated with thaspine. Thaspine has the effects of anti-tumor and inducing apoptosis.

  2. Effect of long interval between hyperthermochemoradiation therapy and surgery for rectal cancer on apoptosis, proliferation and tumor response.

    Science.gov (United States)

    Kato, Toshihide; Fujii, Takaaki; Ide, Munenori; Takada, Takahiro; Sutoh, Toshinaga; Morita, Hiroki; Yajima, Reina; Yamaguchi, Satoru; Tsutsumi, Soichi; Asao, Takayuki; Oyama, Tetsunari; Kuwano, Hiroyuki

    2014-06-01

    Neoadjuvant chemoradiotherapy is commonly used to improve the local control and resectability of locally advanced rectal cancer, with surgery performed after an interval of a number of weeks. We have been conducting a clinical trial of preoperative chemoradiotherapy in combination with regional hyperthermia (hyperthermo-chemoradiation therapy; HCRT) for locally advanced rectal cancer. In the current study we assessed the effect of a longer (>10 weeks) interval after neoadjuvant HCRT on pathological response, oncological outcome and especially on apoptosis, proliferation and p53 expression in patients with rectal cancer. Forty-eight patients with proven rectal adenocarcinoma who underwent HCRT followed by surgery were identified for inclusion in this study. Patients were divided into two groups according to the interval between HCRT and surgery, ≤ 10 weeks (short-interval group) and >10 weeks (long-interval group). Patients in the long-interval group had a significantly higher rate of pathological complete response (pCR) (43.5% vs. 16.0%) than patients of the short-interval group. Patients of the long-interval group had a significantly higher rate of down-staging of T-stage (78.3% vs. 36.0%) and relatively higher rate of that of N-stage (52.2% vs. 36.0%) than patients of the short-interval group. Furthermore, apoptosis in the long-interval group was relatively higher compared to that of the short-interval group, without a significant difference in the Ki-67 proliferative index and expression of p53 in the primary tumor. In conclusion, we demonstrated that a longer interval after HCRT (>10 weeks) seemed to result in a better chance of a pCR, a result confirmed by the trends in tumor response markers, including apoptosis, proliferation and p53 expression. Copyright© 2014 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  3. Gender Differences in Response to Prolonged Every-Other-Day Feeding on the Proliferation and Apoptosis of Hepatocytes in Mice.

    Science.gov (United States)

    Piotrowska, Katarzyna; Tarnowski, Maciej; Zgutka, Katarzyna; Pawlik, Andrzej

    2016-03-19

    Intermittent fasting decreases glucose and insulin levels and increases insulin sensitivity and lifespan. Decreased food intake influences the liver. Previous studies have shown gender differences in response to various types of caloric restriction, including every-other-day (EOD) feeding, in humans and rodents. Our goal was to show the influence of prolonged EOD feeding on the morphology, proliferation and apoptosis of livers from male and female mice. After nine months of an EOD diet, the livers from male and female mice were collected. We examined their morphology on histological slides using the Hematoxilin and Eosine (H_E) method and Hoechst staining of cell nuclei to evaluate the nuclear area of hepatocytes. We also evaluated the expression of mRNA for proto-oncogens, pro-survival proteins and apoptotic markers using Real Time Polimerase Chain Reaction (PCR). We noted increased lipid content in the livers of EOD fed female mice. EOD feeding lead to a decrease of proliferation and apoptosis in the livers of female and male mice, which suggest that tissue maintenance occurred during EOD feeding. Our experiment revealed sex-specific expression of mRNA for proto-oncogenes and pro-survival and pro-apoptotic genes in mice as well as sex-specific responses to the EOD treatment.

  4. Gender Differences in Response to Prolonged Every-Other-Day Feeding on the Proliferation and Apoptosis of Hepatocytes in Mice

    Directory of Open Access Journals (Sweden)

    Katarzyna Piotrowska

    2016-03-01

    Full Text Available Intermittent fasting decreases glucose and insulin levels and increases insulin sensitivity and lifespan. Decreased food intake influences the liver. Previous studies have shown gender differences in response to various types of caloric restriction, including every-other-day (EOD feeding, in humans and rodents. Our goal was to show the influence of prolonged EOD feeding on the morphology, proliferation and apoptosis of livers from male and female mice. After nine months of an EOD diet, the livers from male and female mice were collected. We examined their morphology on histological slides using the Hematoxilin and Eosine (H_E method and Hoechst staining of cell nuclei to evaluate the nuclear area of hepatocytes. We also evaluated the expression of mRNA for proto-oncogens, pro-survival proteins and apoptotic markers using Real Time Polimerase Chain Reaction (PCR. We noted increased lipid content in the livers of EOD fed female mice. EOD feeding lead to a decrease of proliferation and apoptosis in the livers of female and male mice, which suggest that tissue maintenance occurred during EOD feeding. Our experiment revealed sex-specific expression of mRNA for proto-oncogenes and pro-survival and pro-apoptotic genes in mice as well as sex-specific responses to the EOD treatment.

  5. Apoptosis-Dependent and Apoptosis-Independent Functions Bim in Prostate Cancer Cells

    National Research Council Canada - National Science Library

    Liu, Junwei

    2004-01-01

    ... (death, survival, proliferation/division, etc). Our hypothesis is that, under normal, unstimulated conditions, with its apoptotic function blocked, the upregulated Bim in PCa cells play an apoptosis-independent function...

  6. miR-320a regulates cell proliferation and apoptosis in multiple myeloma by targeting pre-B-cell leukemia transcription factor 3

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Yinghao [Jiangsu Institute of Hematology, First Affiliated Hospital of Soochow University, Key Laboratory of Thrombosis and Hemostasis Under Ministry of Health, Collaborative Innovation Center of Hematology, Suzhou, 215006 (China); Department of Hematology, Affiliated Hospital of Guizhou Medical University, The Hematopoietic Stem Cell Transplant Center of Guizhou Province, Blood Diseases Diagnosis and Treatment Center of Guizhou Province, Guiyang, 550004, Guizhou Province (China); Wu, Depei, E-mail: wudepei@medmail.com.cn [Jiangsu Institute of Hematology, First Affiliated Hospital of Soochow University, Key Laboratory of Thrombosis and Hemostasis Under Ministry of Health, Collaborative Innovation Center of Hematology, Suzhou, 215006 (China); Wang, Jishi, E-mail: lgylhlyh@aliyun.com [Department of Hematology, Affiliated Hospital of Guizhou Medical University, The Hematopoietic Stem Cell Transplant Center of Guizhou Province, Blood Diseases Diagnosis and Treatment Center of Guizhou Province, Guiyang, 550004, Guizhou Province (China); Li, Yan; Chai, Xiao; Kang, Qian [Department of Hematology, Affiliated Hospital of Guizhou Medical University, The Hematopoietic Stem Cell Transplant Center of Guizhou Province, Blood Diseases Diagnosis and Treatment Center of Guizhou Province, Guiyang, 550004, Guizhou Province (China)

    2016-05-13

    Aberrant expression of microRNAs (miRNAs) is implicated in cancer development and progression. While miR-320a is reported to be deregulated in many malignancy types, its biological role in multiple myeloma (MM) remains unclear. Here, we observed reduced expression of miR-320a in MM samples and cell lines. Ectopic expression of miR-320a dramatically suppressed cell viability and clonogenicity and induced apoptosis in vitro. Mechanistic investigation led to the identification of Pre-B-cellleukemia transcription factor 3 (PBX3) as a novel and direct downstream target of miR-320a. Interestingly, reintroduction of PBX3 abrogated miR-320a-induced MM cell growth inhibition and apoptosis. In a mouse xenograft model, miR-320a overexpression inhibited tumorigenicity and promoted apoptosis. Our findings collectively indicate that miR-320a inhibits cell proliferation and induces apoptosis in MM cells by directly targeting PBX3, supporting its utility as a novel and potential therapeutic agent for miRNA-based MM therapy. -- Highlights: •Expression of miR-320a in MM cell induces apoptosis in vitro. •miR-320a represses PBX3 via targeting specific sequences in the 3′UTR region. •Exogenous expression of PBX3 reverses the effects of miR-320a in inhibiting MM cell growth and promoting apoptosis. •Overexpression of miR-320a inhibits tumor growth and increases apoptosis in vivo.

  7. [Effects of icotinib hydrochloride on the proliferation and apoptosis of human lung cancer cell lines].

    Science.gov (United States)

    Ma, Li; Han, Xiao-hong; Wang, Shuai; Wang, Jian-fei; Shi, Yuan-kai

    2012-09-25

    To explore the effects of icotinib on the proliferation and apoptosis of various lung cancer cell lines. Human lung cancer cell lines HCC827, H1650, H1975, A549 and human epidermal cancer cell line A431 were treated in vitro with icotinib or gefitinib at a concentration gradient of 0 - 40 µmol/L. Their proliferation effects were analyzed by the thiazolyl blue (MTT) assay and the apoptotic effects detected by flow cytometer. The downstream signaling proteins were detected by Western blot. The median inhibitory concentrations (IC(50)) of icotinib for A431 and HCC827 cell lines were (0.04 ± 0.02) and (0.15 ± 0.06) µmol/L respectively. No significant differences existed between the inhibitions of gefitinib and icotinib on A431, HCC827, H1650, H1975 and A549 cell lines (all P > 0.05). Compared with H1650, H1975 and A549 cell lines, icotinib significantly inhibited A431 (P = 0.009, 0.005 and 0.000) and HCC827 (P = 0.001, 0.001 and 0.000) cell lines. And it lowered the expressions of p-AKT, p-ERK and survivin protein expression through the inhibited activity of p-EGFR protein. Icotinib can arrest the proliferation of lung adenocarcinoma cells with EGFR mutation or over-expression by inhibiting the signal pathways of AKT-ERK and survivin.

  8. The relationship between apoptosis and the expression of proliferating cell nuclear antigen and the clinical stages in gastric carcinoma.

    Science.gov (United States)

    Tao, K; Chen, D; Tian, Y; Lu, X; Yang, X

    2000-01-01

    The relationship between the apoptosis and the expression of proliferating cell nuclear antigen (PCNA) and the clinical stages in gastric cancers was studied. By using terminal deoxynucleotidyl transferase-mediated nick end labeling (TUNEL) technique and PCNA immunohistochemical staining, the apoptosis and the expression of PCNA in tissue of gastric carcinoma were assayed in situ, the index of apoptosis (AI), index of PCNA (PI) and the rate of AI/PI were calculated. AI and PI in gastric cancer tissues were (6.5 +/- 3.7)% and (49.8 +/- 15.9)% respectively, and the rate of AI/PI was 0.13 +/- 0.05, which were obviously different from those of normal gastric mucosa in paragastric cancer (P stages of gastric carcinoma, the AI was decreased, PI was increased and the rate of AI/PI decreased in gastric carcinoma. There was significant difference in them between the gastric cancer tissues and normal gastric mucosa in pericarcinoma in TNM stage II to IV (P gastric carcinoma. The AI, PI and the rate of AI/PI would become the prognostic factors in advanced gastric carcinoma.

  9. Senescence-Associated Secretory Phenotypes Reveal Cell-Nonautonomous Functions of Oncogenic RAS and the p53 Tumor Suppressor

    Energy Technology Data Exchange (ETDEWEB)

    Copp& #233; , Jean-Philippe; Patil, Christopher; Rodier, Francis; Sun, Yu; Munoz, Denise; Goldstein, Joshua; Nelson, Peter; Desprez, Pierre-Yves; Campisi, Judith

    2008-10-24

    Cellular senescence suppresses cancer by arresting cell proliferation, essentially permanently, in response to oncogenic stimuli, including genotoxic stress. We modified the use of antibody arrays to provide a quantitative assessment of factors secreted by senescent cells. We show that human cells induced to senesce by genotoxic stress secrete myriad factors associated with inflammation and malignancy. This senescence-associated secretory phenotype (SASP) developed slowly over several days and only after DNA damage of sufficient magnitude to induce senescence. Remarkably similar SASPs developed in normal fibroblasts, normal epithelial cells, and epithelial tumor cells after genotoxic stress in culture, and in epithelial tumor cells in vivo after treatment of prostate cancer patients with DNA-damaging chemotherapy. In cultured premalignant epithelial cells, SASPs induced an epithelial-mesenchyme transition and invasiveness, hallmarks of malignancy, by a paracrine mechanism that depended largely on the SASP factors interleukin (IL)-6 and IL-8. Strikingly, two manipulations markedly amplified, and accelerated development of, the SASPs: oncogenic RAS expression, which causes genotoxic stress and senescence in normal cells, and functional loss of the p53 tumor suppressor protein. Both loss of p53 and gain of oncogenic RAS also exacerbated the promalignant paracrine activities of the SASPs. Our findings define a central feature of genotoxic stress-induced senescence. Moreover, they suggest a cell-nonautonomous mechanism by which p53 can restrain, and oncogenic RAS can promote, the development of age-related cancer by altering the tissue microenvironment.

  10. Acrolein-Exposed Normal Human Lung Fibroblasts in Vitro: Cellular Senescence, Enhanced Telomere Erosion, and Degradation of Werner’s Syndrome Protein

    Science.gov (United States)

    Jang, Jun-Ho; Bruse, Shannon; Huneidi, Salam; Schrader, Ronald M.; Monick, Martha M.; Lin, Yong; Carter, A. Brent; Klingelhutz, Aloysius J.

    2014-01-01

    Background: Acrolein is a ubiquitous environmental hazard to human health. Acrolein has been reported to activate the DNA damage response and induce apoptosis. However, little is known about the effects of acrolein on cellular senescence. Objectives: We examined whether acrolein induces cellular senescence in cultured normal human lung fibroblasts (NHLF). Methods: We cultured NHLF in the presence or absence of acrolein and determined the effects of acrolein on cell proliferative capacity, senescence-associated β-galactosidase activity, the known senescence-inducing pathways (e.g., p53, p21), and telomere length. Results: We found that acrolein induced cellular senescence by increasing both p53 and p21. The knockdown of p53 mediated by small interfering RNA (siRNA) attenuated acrolein-induced cellular senescence. Acrolein decreased Werner’s syndrome protein (WRN), a member of the RecQ helicase family involved in DNA repair and telomere maintenance. Acrolein-induced down-regulation of WRN protein was rescued by p53 knockdown or proteasome inhibition. Finally, we found that acrolein accelerated p53-mediated telomere shortening. Conclusions: These results suggest that acrolein induces p53-mediated cellular senescence accompanied by enhanced telomere attrition and WRN protein down-regulation. Citation: Jang JH, Bruse S, Huneidi S, Schrader RM, Monick MM, Lin Y, Carter AB, Klingelhutz AJ, Nyunoya T. 2014. Acrolein-exposed normal human lung fibroblasts in vitro: cellular senescence, enhanced telomere erosion, and degradation of Werner’s syndrome protein. Environ Health Perspect 122:955–962; http://dx.doi.org/10.1289/ehp.1306911 PMID:24747221

  11. Suppressed Expression of T-Box Transcription Factors is Involved in Senescence in Chronic Obstructive Pulmonary Disease

    Energy Technology Data Exchange (ETDEWEB)

    Acquaah-Mensah, George; Malhotra, Deepti; Vulimiri, Madhulika; McDermott, Jason E.; Biswal, Shyam

    2012-06-19

    Chronic obstructive pulmonary disease (COPD) is a major global health problem. The etiology of COPD has been associated with apoptosis, oxidative stress, and inflammation. However, understanding of the molecular interactions that modulate COPD pathogenesis remains only partly resolved. We conducted an exploratory study on COPD etiology to identify the key molecular participants. We used information-theoretic algorithms including Context Likelihood of Relatedness (CLR), Algorithm for the Reconstruction of Accurate Cellular Networks (ARACNE), and Inferelator. We captured direct functional associations among genes, given a compendium of gene expression profiles of human lung epithelial cells. A set of genes differentially expressed in COPD, as reported in a previous study were superposed with the resulting transcriptional regulatory networks. After factoring in the properties of the networks, an established COPD susceptibility locus and domain-domain interactions involving protein products of genes in the generated networks, several molecular candidates were predicted to be involved in the etiology of COPD. These include COL4A3, CFLAR, GULP1, PDCD1, CASP10, PAX3, BOK, HSPD1, PITX2, and PML. Furthermore, T-box (TBX) genes and cyclin-dependent kinase inhibitor 2A (CDKN2A), which are in a direct transcriptional regulatory relationship, emerged as preeminent participants in the etiology of COPD by means of senescence. Contrary to observations in neoplasms, our study reveals that the expression of genes and proteins in the lung samples from patients with COPD indicate an increased tendency towards cellular senescence. The expression of the anti-senescence mediators TBX transcription factors, chromatin modifiers histone deacetylases, and sirtuins was suppressed; while the expression of TBX-regulated cellular senescence markers such as CDKN2A, CDKN1A, and CAV1 was elevated in the peripheral lung tissue samples from patients with COPD. The critical balance between senescence

  12. Alpha cyano-4-hydroxy-3-methoxycinnamic acid inhibits proliferation and induces apoptosis in human breast cancer cells.

    Science.gov (United States)

    Hamdan, Lamia; Arrar, Zoheir; Al Muataz, Yacoub; Suleiman, Lutfi; Négrier, Claude; Mulengi, Joseph Kajima; Boukerche, Habib

    2013-01-01

    This study investigated the underlying mechanism of 4-hydroxy-3-methoxycinnamic acid (ACCA), on the growth of breast cancer cells and normal immortal epithelial cells, and compared their cytotoxic effects responses. Treatment of breast cancer cells (MCF-7, T47D, and MDA-231) with ACCA resulted in dose- and time-dependent decrease of cell proliferation, viability in colony formation assay, and programmed cell death (apoptosis) with minimal effects on non-tumoral cells. The ability of ACCA to suppress growth in cancer cells not expressing or containing defects in p53 gene indicates a lack of involvement of this critical tumor suppressor element in mediating ACCA-induced growth inhibition. Induction of apoptosis correlated with an increase in Bax protein, an established inducer of programmed cell death, and the ratio of Bax to Bcl-2, an established inhibitor of apoptosis. We also documented the ability of ACCA to inhibit the migration and invasion of MDA-231 cells with ACCA in vitro. Additionally, tumor growth of MDA-231 breast cancer cells in vivo was dramatically affected with ACCA. On the basis of its selective anticancer inhibitory activity on tumor cells, ACCA may represent a promising therapeutic drug that should be further evaluated as a chemotherapeutic agent for human breast cancer.

  13. Alpha cyano-4-hydroxy-3-methoxycinnamic acid inhibits proliferation and induces apoptosis in human breast cancer cells.

    Directory of Open Access Journals (Sweden)

    Lamia Hamdan

    Full Text Available This study investigated the underlying mechanism of 4-hydroxy-3-methoxycinnamic acid (ACCA, on the growth of breast cancer cells and normal immortal epithelial cells, and compared their cytotoxic effects responses. Treatment of breast cancer cells (MCF-7, T47D, and MDA-231 with ACCA resulted in dose- and time-dependent decrease of cell proliferation, viability in colony formation assay, and programmed cell death (apoptosis with minimal effects on non-tumoral cells. The ability of ACCA to suppress growth in cancer cells not expressing or containing defects in p53 gene indicates a lack of involvement of this critical tumor suppressor element in mediating ACCA-induced growth inhibition. Induction of apoptosis correlated with an increase in Bax protein, an established inducer of programmed cell death, and the ratio of Bax to Bcl-2, an established inhibitor of apoptosis. We also documented the ability of ACCA to inhibit the migration and invasion of MDA-231 cells with ACCA in vitro. Additionally, tumor growth of MDA-231 breast cancer cells in vivo was dramatically affected with ACCA. On the basis of its selective anticancer inhibitory activity on tumor cells, ACCA may represent a promising therapeutic drug that should be further evaluated as a chemotherapeutic agent for human breast cancer.

  14. Cell proliferation and apoptosis in optic nerve and brain integration centers of adult trout Oncorhynchus mykiss after optic nerve injury

    Science.gov (United States)

    Pushchina, Evgeniya V.; Shukla, Sachin; Varaksin, Anatoly A.; Obukhov, Dmitry K.

    2016-01-01

    Fishes have remarkable ability to effectively rebuild the structure of nerve cells and nerve fibers after central nervous system injury. However, the underlying mechanism is poorly understood. In order to address this issue, we investigated the proliferation and apoptosis of cells in contralateral and ipsilateral optic nerves, after stab wound injury to the eye of an adult trout Oncorhynchus mykiss. Heterogenous population of proliferating cells was investigated at 1 week after injury. TUNEL labeling gave a qualitative and quantitative assessment of apoptosis in the cells of optic nerve of trout 2 days after injury. After optic nerve injury, apoptotic response was investigated, and mass patterns of cell migration were found. The maximal concentration of apoptotic bodies was detected in the areas of mass clumps of cells. It is probably indicative of massive cell death in the area of high phagocytic activity of macrophages/microglia. At 1 week after optic nerve injury, we observed nerve cell proliferation in the trout brain integration centers: the cerebellum and the optic tectum. In the optic tectum, proliferating cell nuclear antigen (PCNA)-immunopositive radial glia-like cells were identified. Proliferative activity of nerve cells was detected in the dorsal proliferative (matrix) area of the cerebellum and in parenchymal cells of the molecular and granular layers whereas local clusters of undifferentiated cells which formed neurogenic niches were observed in both the optic tectum and cerebellum after optic nerve injury. In vitro analysis of brain cells of trout showed that suspension cells compared with monolayer cells retain higher proliferative activity, as evidenced by PCNA immunolabeling. Phase contrast observation showed mitosis in individual cells and the formation of neurospheres which gradually increased during 1–4 days of culture. The present findings suggest that trout can be used as a novel model for studying neuronal regeneration. PMID:27212918

  15. Postnatal treadmill exercise alleviates short-term memory impairment by enhancing cell proliferation and suppressing apoptosis in the hippocampus of rat pups born to diabetic rats.

    Science.gov (United States)

    Kim, Young Hoon; Sung, Yun-Hee; Lee, Hee-Hyuk; Ko, Il-Gyu; Kim, Sung-Eun; Shin, Mal-Soon; Kim, Bo-Kyun

    2014-08-01

    During pregnancy, diabetes mellitus exerts detrimental effects on the development of the fetus, especially the central nervous system. In the current study, we evaluated the effects of postnatal treadmill exercise on short-term memory in relation with cell proliferation and apoptosis in the hippocampus of rat pups born to streptozotocin (STZ)-induced diabetic maternal rats. Adult female rats were mated with male rats for 24 h. Two weeks after mating, the pregnant female rats were divided into two groups: control group and STZ injection group. The pregnant rats in the STZ injection group were administered 40 mg/kg of STZ intraperitoneally. After birth, the rat pups were divided into the following four groups: control group, control with postnatal exercise group, maternal STZ-injection group, and maternal STZ-injection with postnatal exercise group. The rat pups in the postnatal exercise groups were made to run on a treadmill for 30 min once a day, 5 times per week for 2 weeks beginning 4 weeks after birth. The rat pups born to diabetic rats were shown to have short-term memory impairment with suppressed cell proliferation and increased apoptosis in the hippocampal dentate gyrus. Postnatal treadmill exercise alleviated short-term memory impairment by increased cell proliferation and suppressed apoptosis in the rat pups born to diabetic rats. These findings indicate that postnatal treadmill exercise may be used as a valuable strategy to ameliorate neurodevelopmental problems in children born to diabetics.

  16. Influence of mycotoxin zearalenone and its derivatives (alpha and beta zearalenol on apoptosis and proliferation of cultured granulosa cells from equine ovaries

    Directory of Open Access Journals (Sweden)

    Minoia Paolo

    2006-11-01

    Full Text Available Abstract Background The mycotoxin zearalenone (ZEA and its derivatives, alpha and beta-zearalenol (alpha and beta-ZOL, synthesized by genera Fusarium, often occur as contaminants in cereal grains and animal feeds. The importance of ZEA on reproductive disorders is well known in domestic animals species, particularly in swine and cattle. In the horse, limited data are available to date on the influence of dietary exposure to ZEA on reproductive health and on its in vitro effects on reproductive cells. The aim of this study was to evaluate the effects of ZEA and its derivatives, alpha and beta-ZOL, on granulosa cells (GCs from the ovaries of cycling mares. Methods The cell proliferation was evaluated by using the 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT test after 3 days exposure at different concentrations of ZEA and its derivatives (from 1 × 10-7 to 0.1 microM. The apoptosis induction was evaluated after 1 day exposure, by DNA analysis using flow cytometry. Results An increase in cell proliferation with respect to the control was observed in the presence of ZEA at 1 × 10-3 and 1 × 10-4 microM and apoptosis was induced by all mycotoxins at different concentrations. Conclusion The simultaneous presence of apoptosis and proliferation in GC cultures treated with zearalenones could indicate that these mycotoxins could be effective in inducing follicular atresia. These effects of zearalenones may result from both direct interaction with oestrogen-receptors as well as interaction with the enzymes 3alpha (beta-hydroxysteroid dehydrogenase (HSD, involved in the synthesis and metabolism of endogenous steroid hormones. These cellular disturbances, described for the first time in equine GCs cultured in vitro, could be hypothesized as referred to reproductive failures of unknown ethiology in the mare.

  17. Prenatal exposure to chromium induces early reproductive senescence by increasing germ cell apoptosis and advancing germ cell cyst breakdown in the F1 offspring.

    Science.gov (United States)

    Sivakumar, Kirthiram K; Stanley, Jone A; Arosh, Joe A; Pepling, Melissa E; Burghardt, Robert C; Banu, Sakhila K

    2014-04-01

    Hexavalent chromium (CrVI), one of the more toxic heavy metals, is widely used in more than 50 industries such as chrome plating, welding, wood processing and tanneries. As one of the world's leading producers of chromium compounds, the U.S. is facing growing challenges in protecting human health against multiple adverse effects of CrVI. CrVI is rapidly converted to CrIII intracellularly, and can induce apoptosis through different mechanisms. Our previous studies demonstrated postnatal exposure to CrVI results in a delay or arrest in follicle development and puberty. Pregnant rats were treated with 25 ppm potassium dichromate (CrVI) from gestational day (GD) 9.5 to 14.5 through drinking water, placentae were removed on GD 20, and total Cr was estimated in the placentae; ovaries were removed from the F1 offspring on postnatal day (PND)-1 and various analyses were performed. Our results show that gestational exposure to CrVI resulted in (i) increased Cr concentration in the placenta, (ii) increased germ cell apoptosis by up-regulating p53/p27-Bax-caspase-3 proteins and by increasing p53-SOD-2 co-localization; (iii) accelerated germ cell cyst (GCC) breakdown; (iv) advanced primordial follicle assembly and primary follicle transition and (v) down regulation of p-AKT, p-ERK and XIAP. As a result of the above events, CrVI induced early reproductive senescence and decrease in litter size in F1 female progeny. Published by Elsevier Inc.

  18. Chemosensitizing effects of carbon-based nanomaterials in cancer cells: enhanced apoptosis and inhibition of proliferation as underlying mechanisms

    International Nuclear Information System (INIS)

    Erdmann, Kati; Ringel, Jessica; Rieger, Christiane; Huebner, Doreen; Wirth, Manfred P; Fuessel, Susanne; Hampel, Silke

    2014-01-01

    Recent studies have shown that carbon nanomaterials such as carbon nanofibres (CNFs) and multi-walled carbon nanotubes (CNTs) can exert antitumor activities themselves and sensitize cancer cells to conventional chemotherapeutics such as carboplatin and cisplatin. In the present study, the chemosensitizing effect of CNFs and CNTs on cancer cells of urological origin was investigated regarding the underlying mechanisms. Prostate cancer (DU-145, PC-3) and bladder cancer (EJ28) cells were treated with carbon nanomaterials (CNFs, CNTs) and chemotherapeutics (carboplatin, cisplatin) alone as well as in combination for 24 h. Forty-eight (EJ28) or 72 h (DU-145, PC-3) after the end of treatment the effects on cellular proliferation, clonogenic survival, cell death rate and cell cycle distribution were evaluated. Depending on the cell line, simultaneous administration of chemotherapeutics and carbon nanomaterials produced an additional inhibition of cellular proliferation and clonogenic survival of up to 77% and 98%, respectively, compared to the inhibitory effects of the chemotherapeutics alone. These strongly enhanced antiproliferative effects were accompanied by an elevated cell death rate, which was predominantly mediated via apoptosis and not by necrosis. The antitumor effects of combinations with CNTs were less pronounced than those with CNFs. The enhanced effects of the combinatory treatments on cellular function were mostly of additive to partly synergistic nature. Furthermore, cell cycle analysis demonstrated an arrest at the G2/M phase mediated by a monotreatment with chemotherapeutics. Following combinatory treatments, mostly less than or nearly additive increases of cell fractions in the G2/M phase could be observed. In conclusion, the pronounced chemosensitizing effects of CNFs and CNTs were mediated by an enhanced apoptosis and inhibition of proliferation. The combination of carbon-based nanomaterials and conventional chemotherapeutics represents a novel

  19. Chemosensitizing effects of carbon-based nanomaterials in cancer cells: enhanced apoptosis and inhibition of proliferation as underlying mechanisms

    Science.gov (United States)

    Erdmann, Kati; Ringel, Jessica; Hampel, Silke; Rieger, Christiane; Huebner, Doreen; Wirth, Manfred P.; Fuessel, Susanne

    2014-10-01

    Recent studies have shown that carbon nanomaterials such as carbon nanofibres (CNFs) and multi-walled carbon nanotubes (CNTs) can exert antitumor activities themselves and sensitize cancer cells to conventional chemotherapeutics such as carboplatin and cisplatin. In the present study, the chemosensitizing effect of CNFs and CNTs on cancer cells of urological origin was investigated regarding the underlying mechanisms. Prostate cancer (DU-145, PC-3) and bladder cancer (EJ28) cells were treated with carbon nanomaterials (CNFs, CNTs) and chemotherapeutics (carboplatin, cisplatin) alone as well as in combination for 24 h. Forty-eight (EJ28) or 72 h (DU-145, PC-3) after the end of treatment the effects on cellular proliferation, clonogenic survival, cell death rate and cell cycle distribution were evaluated. Depending on the cell line, simultaneous administration of chemotherapeutics and carbon nanomaterials produced an additional inhibition of cellular proliferation and clonogenic survival of up to 77% and 98%, respectively, compared to the inhibitory effects of the chemotherapeutics alone. These strongly enhanced antiproliferative effects were accompanied by an elevated cell death rate, which was predominantly mediated via apoptosis and not by necrosis. The antitumor effects of combinations with CNTs were less pronounced than those with CNFs. The enhanced effects of the combinatory treatments on cellular function were mostly of additive to partly synergistic nature. Furthermore, cell cycle analysis demonstrated an arrest at the G2/M phase mediated by a monotreatment with chemotherapeutics. Following combinatory treatments, mostly less than or nearly additive increases of cell fractions in the G2/M phase could be observed. In conclusion, the pronounced chemosensitizing effects of CNFs and CNTs were mediated by an enhanced apoptosis and inhibition of proliferation. The combination of carbon-based nanomaterials and conventional chemotherapeutics represents a novel

  20. Abscisic acid as an internal integrator of multiple physiological processes modulates leaf senescence onset in Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Yuwei eSong

    2016-02-01

    Full Text Available Many studies have shown that exogenous abscisic acid (ABA promotes leaf abscission and senescence. However, owing to a lack of genetic evidence, ABA function in plant senescence has not been clearly defined. Here, two-leaf early-senescence mutants (eas that were screened by chlorophyll fluorescence imaging and named eas1-1 and eas1-2 showed high photosynthetic capacity in the early stage of plant growth compared with the wild type. Gene mapping showed that eas1-1 and eas1-2 are two novel ABA2 allelic mutants. Under unstressed conditions, the eas1 mutations caused plant dwarf, early germination, larger stomatal apertures, and early leaf senescence compared with those of the wild type. Flow cytometry assays showed that the cell apoptosis rate in eas1 mutant leaves was higher than that of the wild type after day 30. A significant increase in the transcript levels of several senescence-associated genes, especially SAG12, was observed in eas1 mutant plants in the early stage of plant growth. More importantly, ABA-activated calcium channel activity in plasma membrane and induced the increase of cytoplasmic calcium concentration in guard cells are suppressed due to the mutation of EAS1. In contrast, the eas1 mutants lost chlorophyll and ion leakage significant faster than in the wild type under treatment with calcium channel blocker. Hence, our results indicate that endogenous ABA level is an important factor controlling the onset of leaf senescence through Ca2+ signaling.

  1. Reduced RAC1 activity inhibits cell proliferation and induces apoptosis in neurofibromatosis type 2(NF2)-associated schwannoma.

    Science.gov (United States)

    Wang, Ying; Wang, Bo; Li, Peng; Zhang, Qi; Liu, Pinan

    2017-12-01

    Objective To study the function and potential mechanism of RAC1 inhibitors in NF2-associated schwannoma. Methods In this study, we the downregulation of RAC1 activity and tumor cell phenotypes by RAC1 inhibitor NSC23766 in vitro. And we further validated the anti-proliferation effect by this RAC1 inhibitor in subcutaneous xenograft tumor model and sciatic nerve model. Results Pharmacological inhibition of RAC1 could significantly inhibit the proliferation of both RT4 cells and human NF2-associated primary schwannoma cells by inducing apoptosis. Pharmacological inhibition of RAC1 effectively reduced Rac1 activity and down-regulated the pathway downstream of Rac. Moreover, pharmacological inhibition of RAC1 showed a potential antitumor effect, with low toxicity in vivo. Conclusion RAC1 inhibitors may play a therapeutic role in patients with schwannoma.

  2. Apoptosis-Dependent and Apoptosis-Independent Functions of Bim in Prostate Cancer Cells

    National Research Council Canada - National Science Library

    Tang, Dean; Liu, Junwei

    2005-01-01

    ... (death, survival, proliferation/division, etc.). Our hypothesis is that, under normal, unstimulated conditions, with its apoptotic function blocked, the upregulated Bim in PCa cells plays an apoptosis-independent function...

  3. Influence of 28-O-propynoylbetulin on proliferation and apoptosis of melanotic and amelanotic human melanoma cells

    Directory of Open Access Journals (Sweden)

    Anna Kaps

    2016-12-01

    Full Text Available Introduction: A relatively new approach in treatment of malignant melanoma is the use of betulin and its synthetic derivatives that have anticancer properties. The aim of the study was to determine the effect of an acetylenic derivative of betulin, 28-O-propynoylbetulin, on cell growth and apoptosis induction in human melanotic and amelanotic melanoma cells.Materials and methods: The A2058 and C32 cell lines were incubated with 28-O-propynoylbetulin (working solutions from 0.1 to 10 μg/ml. To evaluate cell proliferation, a sulforhodamine B based assay was conducted. In order to elucidate the early stages of apoptosis in both melanoma cell lines, caspase-3 activity was evaluated.Results: The administration of 28-O-propynoylbetulin at a concentration equal to or less than 1 μg/ml did not cause a statistically significant change in the cell proliferation in either melanoma cell line (compared to control, p>0.05. Higher concentrations of the compound (3 and 10 μg/ml inhibited the cell growth (in comparison to control, p<0.05. These results corresponded with caspase-3 activity results that revealed an increase of enzyme activity after 24-hour incubation with 3 and 10 μg/ml of the compound (compared to control, p<0.05.Discussion: The study revealed that 28-O-propynoylbetulin may have diverse effects on melanoma cells and could be a strong inhibitor of cell growth (C32 cells or exert a more potent proapoptotic effect (A2058 cells. These findings support the possibility of the use of EB5 in different antimelanoma approaches.

  4. Methylcobalamin promotes proliferation and migration and inhibits apoptosis of C2C12 cells via the Erk1/2 signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Okamoto, Michio [Department of Orthopaedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Tanaka, Hiroyuki, E-mail: tanahiro-osk@umin.ac.jp [Department of Orthopaedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Okada, Kiyoshi [Department of Orthopaedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Kuroda, Yusuke [Department of Orthopaedic Surgery, Kansai Rosai Hospital, 3-1-69 Inabaso, Amagasaki, Hyogo 660-8511 (Japan); Nishimoto, Shunsuke; Murase, Tsuyoshi; Yoshikawa, Hideki [Department of Orthopaedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan)

    2014-01-17

    Highlights: •Methylcobalamin activated the Erk1/2 signaling pathway in C2C12 cells. •Methylcobalamin promoted the proliferation and migration in C2C12 cells. •C2C12 cell apoptosis during differentiation was inhibited by methylcobalamin. -- Abstract: Methylcobalamin (MeCbl) is a vitamin B12 analog that has some positive effects on peripheral nervous disorders. Although some previous studies revealed the effects of MeCbl on neurons, its effect on the muscle, which is the final target of motoneuron axons, remains to be elucidated. This study aimed to determine the effect of MeCbl on the muscle. We found that MeCbl promoted the proliferation and migration of C2C12 myoblasts in vitro and that these effects are mediated by the Erk1/2 signaling pathway without affecting the activity of the Akt signaling pathway. We also demonstrated that MeCbl inhibits C2C12 cell apoptosis during differentiation. Our results suggest that MeCbl has beneficial effects on the muscle in vitro. MeCbl administration may provide a novel therapeutic approach for muscle injury or degenerating muscle after denervation.

  5. Effects of MicroRNA-206 on Osteosarcoma Cell Proliferation, Apoptosis, Migration and Invasion by Targeting ANXA2 Through the AKT Signaling Pathway

    Directory of Open Access Journals (Sweden)

    Bao-Long Pan

    2018-02-01

    Full Text Available Background/Aims: This study aimed to investigate the mechanism by which microRNA-206 (miR-206 affects the proliferation, apoptosis, migration and invasion of osteosarcoma (OS cells by targeting ANXA2 via the AKT signaling pathway. Methods: A total of 132 OS tissues and 120 osteochondroma tissues were examined in this study. The targeting relationship between miR-206 and ANXA2 was verified with a dual-luciferase reporter assay. The miR-206 expression and ANXA2, AKT, PARP, FASN, Survivin, Bax, Mcl-1 and Bcl-1 mRNA and protein expression in the above two groups were examined by qRT-PCR and western blotting. The cultured OS cells were divided into 6 groups: a blank group, negative control (NC group, miR-206 mimic group, miR-206 inhibitor group, si-ANXA2 group and miR-206 inhibitor + si-ANXA2 group. Cell cycle and apoptosis were assessed by flow cytometry, cell migration was examined with a wound-healing assay, and cell invasion was assessed with a Transwell assay. Pearson correlation analysis was used to determine the correlation between ANXA2 mRNA expression and miR-206 expression in OS. Results: OS tissues exhibited increased mRNA and protein expression of ANXA2, AKT, PARP, FASN, Survivin, Mcl-1 and Bcl-2; decreased miR-206 expression; and decreased Bax mRNA and protein expression. ANXA2 mRNA expression was strongly negatively correlated with miR-206 expression in OS. ANXA2 was found to be a miR-206 target gene. In the miR-206 mimic group and the si-ANXA2 group, the mRNA and protein expression of ANXA2, AKT, PARP, FASN, Survivin, Mcl-1 and Bcl-1 decreased markedly, cell proliferation was inhibited, apoptosis was promoted, higher cell growth in G1 phase and decreased growth in S phase was detected, and decreased cell migration and invasion were observed compared with those in the blank group. Conclusion: The current results demonstrate that miR-206 overexpression inhibits OS cell proliferation, migration and invasion and promotes apoptosis through

  6. [Overexpression of N-myc downstream regulated gene 2 (NDRG2) inhibits proliferation, migration and promotes apoptosis in SW480 rectal cancer cells].

    Science.gov (United States)

    Li, Zhiqiang; Sun, Yang; Wan, Hongxing; Chai, Fang

    2017-01-01

    Objective To investigate the role of N-myc downstream regulated gene 2 (NDRG2) gene in the proliferation, migration and apoptosis of rectal cancer cells. Methods Human rectal cancer SW480 cells were cultured and transfected with pCDNA3.1-NDRG2 and empty vector (SW480-Ve). SW480 cells were set as a control group. Cell proliferation was detected in SW480 cells, SW480-Ve cells and SW480-NDRG2 cells by MTT assay; cell migration distance in the three groups at 24, 48, 72 hours was tested by wound healing assay; apoptosis rate was determined in the three groups at 48 hours by flow cytometry; the expressions of Bax, caspase-3, Bcl-2 proteins in the three groups were examined by Western blotting. Results After the cells were cultured for 7 days, cell survival rate in SW480-NDRG2 group was significantly lower than that in SW480 cells and SW480-Ve cells; the cell survival rate decreased gradually with the prolongation of the culture time; and it had no significant difference between SW480-Ve group and SW480 group. Cell migration distance in SW480-NDRG2 group was significantly lower than that in SW480-Ve cells and SW480 cells, and it had also no significant difference between SW480-Ve cells and SW480 cells. The apoptosis rate in SW480-NDRG2 group was significantly higher than that in SW480 group and SW480-Ve group, and SW480 cells and SW480-Ve cells had no significant difference in the rate. The expressions of Bax and caspase-3 proteins in SW480-NDRG2 group were significantly higher than those in SW480 cells and SW480-Ve cells; Bcl-2 protein expression was significantly lower in SW480-NDRG2 group than in SW480 cells and SW480-Ve cells; and the expressions of Bax, caspase-3 and Bcl-2 proteins were not significantly different between SW480 cells and SW480-Ve cells. Conclusion Overexpression of NDRG2 can inhibit the proliferation, reduce cell migration, and promote cell apoptosis by regulating the expressions of Bcl-2, Bax and caspase-3 proteins in SW480 cells.

  7. Human herpesvirus 6B inhibits cell proliferation by a p53-independent pathway

    DEFF Research Database (Denmark)

    Øster, Bodil; Kaspersen, M.D.; Kofod-Olsen, Emil

    2006-01-01

    BACKGROUND: Various forms of cellular stress can activate the tumour suppressor protein p53, an important regulator of cell cycle arrest, apoptosis, and cellular senescence. Cells infected by human herpesvirus 6B (HHV-6B) accumulate aberrant amounts of p53. OBJECTIVES: The aim of this study...

  8. Mesenchymal stem cells cultured under hypoxia escape from senescence via down-regulation of p16 and extracellular signal regulated kinase

    International Nuclear Information System (INIS)

    Jin, Yonghui; Kato, Tomohisa; Furu, Moritoshi; Nasu, Akira; Kajita, Yoichiro; Mitsui, Hiroto; Ueda, Michiko; Aoyama, Tomoki; Nakayama, Tomitaka; Nakamura, Takashi; Toguchida, Junya

    2010-01-01

    Hypoxia has been considered to affect the properties of tissue stem cells including mesenchymal stem cells (MSCs). Effects of long periods of exposure to hypoxia on human MSCs, however, have not been clearly demonstrated. MSCs cultured under normoxic conditions (20% pO 2 ) ceased to proliferate after 15-25 population doublings, while MSCs cultured under hypoxic conditions (1% pO 2 ) retained the ability to proliferate with an additional 8-20 population doublings. Most of the MSCs cultured under normoxic conditions were in a senescent state after 100 days, while few senescent cells were found in the hypoxic culture, which was associated with a down-regulation of p16 gene expression. MSCs cultured for 100 days under hypoxic conditions were superior to those cultured under normoxic conditions in the ability to differentiate into the chondro- and adipogenic, but not osteogenic, lineage. Among the molecules related to mitogen-activated protein kinase (MAPK) signaling pathways, extracellular signal regulated kinase (ERK) was significantly down-regulated by hypoxia, which helped to inhibit the up-regulation of p16 gene expression. Therefore, the hypoxic culture retained MSCs in an undifferentiated and senescence-free state through the down-regulation of p16 and ERK.

  9. Plant senescence and crop productivity

    DEFF Research Database (Denmark)

    Gregersen, Per L.; Culetic, Andrea; Boschian, Luca

    2013-01-01

    Senescence is a developmental process which in annual crop plants overlaps with the reproductive phase. Senescence might reduce crop yield when it is induced prematurely under adverse environmental conditions. This review covers the role of senescence for the productivity of crop plants....... With the aim to enhance productivity, a number of functional stay-green cultivars have been selected by conventional breeding, in particular of sorghum and maize. In many cases, a positive correlation between leaf area duration and yield has been observed, although in a number of other cases, stay...... plants, the expression of the IPT gene under control of senescence-associated promoters has been the most successful. The promoters employed for senescence-regulated expression contain