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Sample records for mrna inhibits proliferation

  1. An oligomer complementary to c-myc mRNA inhibits proliferation of HL-60 promyelocytic cells and induces differentiation.

    PubMed Central

    Holt, J T; Redner, R L; Nienhuis, A W

    1988-01-01

    To study the role of a nuclear proto-oncogene in the regulation of cell growth and differentiation, we inhibited HL-60 c-myc expression with a complementary antisense oligomer. This oligomer was stable in culture and entered cells, forming an intracellular duplex. Incubation of cells with the anti-myc oligomer decreased the steady-state levels of c-myc protein by 50 to 80%, whereas a control oligomer did not significantly affect the c-myc protein concentration. Direct inhibition of c-myc expression with the anti-myc oligomer was associated with a decreased cell growth rate and an induction of myeloid differentiation. Related antisense oligomers with 2- to 12-base-pair mismatches with c-myc mRNA did not influence HL-60 cells. Thus, the effects of the antisense oligomer exhibited sequence specificity, and furthermore, these effects could be reversed by hybridization competition with another complementary oligomer. Antisense inhibition of a nuclear proto-oncogene apparently bypasses cell surface events in affecting cell proliferation and differentiation. Images PMID:3280975

  2. Runx3 Expression Inhibits Proliferation and Distinctly Alters mRNA Expression of Bax in AGS and A549 Cancer Cells

    PubMed Central

    Torshabi, Maryam; Faramarzi, Mohammad Ali; Tabatabaei Yazdi, Mojtaba; Ostad, Seyyed Naser; Gharemani, Mohammad Hosein

    2011-01-01

    Runx3, a member of Runt-related transcription factor (Runx) proteins with tumor suppressor effect, is a tissue–restricted and cancer related transcription factor that regulate cell proliferation and growth, as well as differentiation. In the present study, exogenous Run3 was transiently expressed in AGS (human gastric adenocarcinoma), with undetectable Runx3 protein and in A549 (human lung carcinoma) with low levels of endogenous Runx3 protein. The GFP tagged Runx3 was transfected into AGS and A549 cells using fugene6 and PolyFect and Runx3 expression was confirmed by fluorescent microscopy and RT-PCR. The effect of Runx3 transfection on cell proliferation was determined by MTT assay and the results were confirmed by the trypan blue dye exclusion method. The effect of Runx3 expression on mRNA expression of BCL2-associated X protein (Bax) was evaluated using RT-PCR. In AGS and A549 cells, Runx3 expression inhibited cell proliferation (p < 0.01). The growth inhibition was less in A549 cells. We show that Runx3 expression increases Bax mRNA expression in AGS cells when compared with control (p < 0.05), but no significant differences in mRNA expression was observed in both examined cells. Runx3 expression has antiproliferative effect in AGS cell perhaps via increase in expression of Bax. The effect of Runx3 on A549 cells’ viability which has endogenous level of Runx3 is not related to Bax. These findings implicate a complex regulation by Runx3 in inhibition of cell proliferation utilizing Bax. PMID:24250365

  3. BTG/Tob family members Tob1 and Tob2 inhibit proliferation of mouse embryonic stem cells via Id3 mRNA degradation

    SciTech Connect

    Chen, Yuanfan; Wang, Chenchen; Wu, Jenny; Li, Lingsong

    2015-07-03

    The mammalian BTG/Tob family is a group of proteins with anti-proliferative ability, and there are six members including BTG1, BTG2/PC3/Tis21, BTG3/ANA, BTG4/PC3B, Tob1/Tob and Tob2. Among them, Tob subfamily members, specifically Tob1/Tob and Tob2, have the most extensive C-terminal regions. As previously reported, overexpression of BTG/Tob proteins is associated with the inhibition of G1 to S-phase cell cycle progression and decreased cell proliferation in a variety of cell types. Tob subfamily proteins have similar anti-proliferative effects on cell cycle progression in cultured tumor cells. An important unresolved question is whether or not they have function in rapidly proliferating cells, such as embryonic stem cells (ESCs). Tob1 and Tob2 were expressed ubiquitously in mouse ESCs (mESCs), suggesting a possible role in early embryonic development and mESCs. To address the above question and explore the possible functions of the Tob subfamily in ESCs, we established ESCs from different genotypic knockout inner cell mass (ICM). We found that Tob1{sup −/−}, Tob2{sup −/−}, and Tob1/2 double knockout (DKO, Tob1{sup −/−} & Tob2{sup −/−}) ESCs grew faster than wild type (WT) ESCs without losing pluripotency, and we provide a possible mechanistic explanation for these observations: Tob1 and Tob2 inhibit the cell cycle via degradation of Id3 mRNA, which is a set of directly targeted genes of BMP4 signaling in mESCs that play critical roles in the maintenance of ESC properties. Together, our data suggest that BTG/Tob family protein Tob1 and Tob2 regulation cell proliferation does not compromise the basic properties of mESCs. - Highlights: • We established mouse Tob1/2 double knockout embryonic stem cells. • Tob1 and Tob2 inhibit the proliferation of ESCs without effect on pluripotency. • Tob1 and Tob2 involved in the degradation of Id3 in mESCs.

  4. Inorganic sulfur reduces cell proliferation by inhibiting of ErbB2 and ErbB3 protein and mRNA expression in MDA-MB-231 human breast cancer cells

    PubMed Central

    Ha, Ae Wha; Hong, Kyung Hee; Kim, Hee Sun

    2013-01-01

    Dietary inorganic sulfur is the minor component in our diet, but some studies suggested that inorganic sulfur is maybe effective to treat cancer related illness. Therefore, this study aims to examine the effects of inorganic sulfur on cell proliferation and gene expression in MDA-MB-231 human breast cancer cells. MDA-MB-231 cells were cultured the absence or presence of various concentrations (12.5, 25, or 50 µmol/L) of inorganic sulfur. Inorganic sulfur significantly decreased proliferation after 72 h of incubation (P < 0.05). The protein expression of ErbB2 and its active form, pErbB2, were significantly reduced at inorganic sulfur concentrations of 50 µmol/L and greater than 25 µmol/L, respectively (P < 0.05). The mRNA expression of ErbB2 was significantly reduced at an inorganic sulfur concentration of 50 µmol/L (P < 0.05). The protein expression of ErbB3 and its active form, pErbB3, and the mRNA expression of ErbB3 were significantly reduced at inorganic sulfur concentrations greater than 25 µmol/L (P < 0.05). The protein and mRNA expression of Akt were significantly reduced at an inorganic sulfur concentration of 50 µmol/L (P < 0.05), but pAkt was not affected by inorganic sulfur treatment. The protein and mRNA expression of Bax were significantly increased with the addition of inorganic sulfur concentration of 50 µmol/L (P < 0.05). In conclusion, cell proliferation was suppressed by inorganic sulfur treatment through the ErbB-Akt pathway in MDA-MB-231 cells. PMID:23610600

  5. Inhibiting macrophage proliferation suppresses atherosclerotic plaque inflammation

    PubMed Central

    Tang, Jun; Lobatto, Mark E.; Hassing, Laurien; van der Staay, Susanne; van Rijs, Sarian M.; Calcagno, Claudia; Braza, Mounia S.; Baxter, Samantha; Fay, Francois; Sanchez-Gaytan, Brenda L.; Duivenvoorden, Raphaël; Sager, Hendrik B.; Astudillo, Yaritzy M.; Leong, Wei; Ramachandran, Sarayu; Storm, Gert; Pérez-Medina, Carlos; Reiner, Thomas; Cormode, David P.; Strijkers, Gustav J.; Stroes, Erik S. G.; Swirski, Filip K.; Nahrendorf, Matthias; Fisher, Edward A.; Fayad, Zahi A.; Mulder, Willem J. M.

    2015-01-01

    Inflammation drives atherosclerotic plaque progression and rupture, and is a compelling therapeutic target. Consequently, attenuating inflammation by reducing local macrophage accumulation is an appealing approach. This can potentially be accomplished by either blocking blood monocyte recruitment to the plaque or increasing macrophage apoptosis and emigration. Because macrophage proliferation was recently shown to dominate macrophage accumulation in advanced plaques, locally inhibiting macrophage proliferation may reduce plaque inflammation and produce long-term therapeutic benefits. To test this hypothesis, we used nanoparticle-based delivery of simvastatin to inhibit plaque macrophage proliferation in apolipoprotein E–deficient mice (Apoe−/−) with advanced atherosclerotic plaques. This resulted in the rapid reduction of plaque inflammation and favorable phenotype remodeling. We then combined this short-term nanoparticle intervention with an 8-week oral statin treatment, and this regimen rapidly reduced and continuously suppressed plaque inflammation. Our results demonstrate that pharmacologically inhibiting local macrophage proliferation can effectively treat inflammation in atherosclerosis. PMID:26295063

  6. Inhibition of fibroblast proliferation by Actinobacillus actinomycetemcomitans.

    PubMed Central

    Shenker, B J; Kushner, M E; Tsai, C C

    1982-01-01

    We have examined soluble sonic extracts of Actinobacillus actinomycetemcomitans for their ability to alter human and murine fibroblast proliferation. We found that extracts of all A. actinomycetemcomitans strains examined (both leukotoxic and nonleukotoxic) caused a dose-dependent inhibition of both murine and human fibroblast proliferation as assessed by DNA synthesis ([3H]thymidine incorporation). Addition of sonic extract simultaneously with [3H]thymidine had no effect on incorporation, indicating that suppression was not due to the presence of excessive amounts of cold thymidine. Inhibition of DNA synthesis was also paralleled by decreased RNA synthesis ([3H]uridine incorporation) and by a decrease in cell growth as assessed by direct cell counts; there was no effect on cell viability. The suppressive factor(s) is heat labile; preliminary purification and characterization studies indicate that it is a distinct and separate moiety from other A. actinomycetemcomitans mediators previously reported, including leukotoxin, immune suppressive factor, and endotoxin. Although it is not clear how A. actinomycetemcomitans acts to cause disease, we propose that one aspect of the pathogenicity of this organism rests in its ability to inhibit fibroblast growth, which in turn could contribute to the collagen loss associated with certain forms of periodontal disease, in particular juvenile periodontitis. PMID:7152684

  7. TLR2 Activation Inhibits Embryonic Neural Progenitor Cell Proliferation

    PubMed Central

    Okun, Eitan; Griffioen, Kathleen J.; Gen-Son, Tae; Lee, Jong-Hwan; Roberts, Nicholas J.; Mughal, Mohamed R.; Hutchison, Emmette; Cheng, Aiwu; Arumugam, Thiruma V.; Lathia, Justin D.; van Praag, Henriette; Mattson, Mark P.

    2010-01-01

    Toll-like receptors (TLRs) play essential roles in innate immunity, and increasing evidence indicates that these receptors are expressed in neurons, astrocytes and microglia in the brain, where they mediate responses to infection, stress and injury. To address the possibility that TLR2 heterodimer activation could affect progenitor cells in the developing brain, we analyzed the expression of TLR2 throughout the mouse cortical development, and assessed the role of TLR2 heterodimer activation in neural progenitor cell (NPC) proliferation. TLR2 mRNA and protein was expressed in the cortex in embryonic and early postnatal stages of development, and in cultured cortical NPC. While NPC from TLR2-deficient and wild type embryos had the same proliferative capacity, TLR2 activation by the synthetic bacterial lipopeptides Pam3CSK4 and FSL1, or low molecular weight hyaluronan, an endogenous ligand for TLR2, inhibited neurosphere formation in vitro. Intracerebral in utero administration of TLR2 ligands resulted in ventricular dysgenesis characterized by increased ventricle size, reduced proliferative area around the ventricles, increased cell density, an increase in PH3+ cells and a decrease in BrdU+ cells in the sub-ventricular zone. Our findings indicate that loss of TLR2 does not result in defects in cerebral development. However, TLR2 is expressed and functional in the developing telencephalon from early embryonic stages and infectious agent-related activation of TLR2 inhibits NPC proliferation. TLR2–mediated inhibition of NPC proliferation may therefore be a mechanism by which infection, ischemia and inflammation adversely affect brain development. PMID:20456021

  8. Activation of GPR30 inhibits cardiac fibroblast proliferation.

    PubMed

    Wang, Hao; Zhao, Zhuo; Lin, Marina; Groban, Leanne

    2015-07-01

    The incidence of left ventricular diastolic dysfunction significantly increases in postmenopausal women suggesting the association between estrogen loss and diastolic dysfunction. The in vivo activation of G protein-coupled estrogen receptor (GPR30) attenuates the adverse effects of estrogen loss on cardiac fibrosis and diastolic dysfunction in mRen2.Lewis rats. This study was designed to address the effects of GPR30 on cardiac fibroblast proliferation in rats. The expression of GPR30 in cardiac fibroblasts isolated from adult Sprague-Dawley rats was confirmed by RT-PCR, Western blot analysis, and immunofluorescence staining. Results from BrdU incorporation assays, cell counting, carboxyfluorescein diacetate succinimidyl ester labeling in conjunction with flow cytometry, and Ki-67 staining showed that treatment with G1, a specific agonist of GPR30, inhibited cardiac fibroblast proliferation in a dose-dependent manner, which was associated with decreases in CDK1 and cyclin B1 protein expressions. In the GPR30-KO cells, BrdU incorporation, and CDK1 and cyclin B1 expressions significantly increased when compared to GPR30-intact cells. G1 had no effect on BrdU incorporation, CDK1 and cyclin B1 mRNA levels in GPR30-KO cells. In vivo studies showed increases in CDK1 and cyclin B1 mRNA levels, Ki-67-positive cells, and the immunohistochemistry staining of vimentin, a fibroblast marker, in the left ventricles from ovariectomized mRen2.Lewis rats versus hearts from ovary-intact littermates; 2 weeks of G1 treatment attenuated these adverse effects of estrogen loss. This study demonstrates that GPR30 is expressed in rat cardiac fibroblasts, and activation of GPR30 limits proliferation of these cells likely via suppression of the cell cycle proteins, cyclin B1, and CDK1. PMID:25893735

  9. SAMHD1 is down regulated in lung cancer by methylation and inhibits tumor cell proliferation

    SciTech Connect

    Wang, Jia-lei; Lu, Fan-zhen; Shen, Xiao-Yong; Wu, Yun; Zhao, Li-ting

    2014-12-12

    Highlights: • SAMHD1 expression level is down regulated in lung adenocarcinoma. • The promoter of SAMHD1 is methylated in lung adenocarcinoma. • Over expression of SAMHD1 inhibits the proliferation of lung cancer cells. - Abstract: The function of dNTP hydrolase SAMHD1 as a viral restriction factor to inhibit the replication of several viruses in human immune cells was well established. However, its regulation and function in lung cancer have been elusive. Here, we report that SAMHD1 is down regulated both on protein and mRNA levels in lung adenocarcinoma compared to adjacent normal tissue. We also found that SAMHD1 promoter is highly methylated in lung adenocarcinoma, which may inhibit its gene expression. Furthermore, over expression of the SAMHD1 reduces dNTP level and inhibits the proliferation of lung tumor cells. These results reveal the regulation and function of SAMHD1 in lung cancer, which is important for the proliferation of lung tumor cells.

  10. CCL5 promotes proliferation of MCF-7 cells through mTOR-dependent mRNA translation

    SciTech Connect

    Murooka, Thomas T.; Rahbar, Ramtin; Fish, Eleanor N.

    2009-09-18

    The proliferative capacity of cancer cells is regulated by factors intrinsic to cancer cells and by secreted factors in the microenvironment. Here, we investigated the proto-oncogenic potential of the chemokine receptor, CCR5, in MCF-7 breast cancer cell lines. At physiological levels, CCL5, a ligand for CCR5, enhanced MCF-7.CCR5 proliferation. Treatment with the mTOR inhibitor, rapamycin, inhibited this CCL5-inducible proliferation. Because mTOR directly modulates mRNA translation, we investigated whether CCL5 activation of CCR5 leads to increased translation. CCL5 induced the formation of the eIF4F translation initiation complex through an mTOR-dependent process. Indeed, CCL5 initiated mRNA translation, shown by an increase in high-molecular-weight polysomes. Specifically, we show that CCL5 mediated a rapid up-regulation of protein expression for cyclin D1, c-Myc and Dad-1, without affecting their mRNA levels. Taken together, we describe a mechanism by which CCL5 influences translation of rapamycin-sensitive mRNAs, thereby providing CCR5-positive breast cancer cells with a proliferative advantage.

  11. [Effects of PTK787 on cell proliferation and expression of fak mRNA in K562].

    PubMed

    Di, Xiao-Hua; Chen, Ri-Ling; Liu, Xiao-Li; Tian, Chuan; Guo, Ya-Nan

    2010-06-01

    The aim of this study was to investigate the effects of tyrosine kinase inhibitor PTK787 on cell proliferation, cell cycle and the expression of fak mRNA of human chronic myeloid leukemia (CML) cell line K562, and to explore the mechanism of PTK787 against acute myeloid leukemia. The MTT method was used to detect the effects of PTK787 in various concentrations and at different time points on proliferation of K562 cells; the flow cytometry was used to determine the effects of PTK787 in different concentrations on cell cycle of K562 cells; the RT-PCR was used to assay the expression of fak mRNA in K562 cells treated with PTK787 for 48 hours. The results showed that along with increasing of the concentration and prolonging of time, the inhibitory rate of PTK787 on K562 proliferation was gradually enhanced. The comparison between various concentration groups at same time or comparison between various time groups in same concentration showed significant differences (p < 0.05), in which the effect of 320 micromol/L PTK787 on cells was strongest, while the continuous increase of PTK787 concentration or prolong of action time did not enhance the inhibitory rate on K562 proliferation. With increasing of drug concentration, the cell proportion in G(1) phase gradually increased, the cell proportion in S phase gradually decreased, the comparison between various groups revealed significant differences (p < 0.05), however the continuous increase of drug concentration from 160 micromol/L did not obviously change the cell proportion in phases of cell cycle. With increasing of drug concentration, the expression of fak mRNA in K562 cells gradually reduced with significant differences between various groups (p < 0.05), but with continuous increase of drug concentration from 160 micromol/L, the effect of PTK787 on the expression of fak mRNA in K562 cells also did not obviously change. It is concluded that the PTK787 shows effect of anti-leukemia cells through inhibiting transformation

  12. Triptolide inhibits COX-2 expression by regulating mRNA stability in TNF-{alpha}-treated A549 cells

    SciTech Connect

    Sun, Lixin; Zhang, Shuang; Jiang, Zhenzhou; Huang, Xin; Wang, Tao; Huang, Xiao; Li, Han; Zhang, Luyong

    2011-12-09

    Highlights: Black-Right-Pointing-Pointer Triptolide inhibited COX-2 expression and the half-life of COX-2 mRNA is decreased. Black-Right-Pointing-Pointer The HuR protein shuttling from nucleus to cytoplasm is inhibited by triptolide. Black-Right-Pointing-Pointer Triptolide inhibited 3 Prime -UTR fluorescence reporter gene activity. Black-Right-Pointing-Pointer COX-2 mRNA binding to HuR is decreased by triptolide in pull-down experiments. -- Abstract: Cyclooxygenase-2 (COX-2) over-expression is frequently associated with human non-small-cell lung cancer (NSCLC) and involved in tumor proliferation, invasion, angiogenesis and resistance to apoptosis. In the present study, the effects of triptolide on COX-2 expression in A549 cells were investigated and triptolide was found to inhibit TNF-{alpha}-induced COX-2 expression. In our further studies, it was found that triptolide decreased the half-life of COX-2 mRNA dramatically and that it inhibited 3 Prime -untranslated region (3 Prime -UTR) fluorescence reporter gene activity. Meanwhile, triptolide inhibited the HuR shuttling from nucleus to cytoplasm. After triptolide treatment, decreased COX-2 mRNA in pull-down experiments with anti-HuR antibodies was observed, indicating that the decreased cytoplasmic HuR is responsible for the decreased COX-2 mRNA. Taken together, our results provided evidence for the first time that triptolide inhibited COX-2 expression by COX-2 mRNA stability modulation and post-transcriptional regulation. These results provide a novel mechanism of action for triptolide which may be important in the treatment of lung cancer.

  13. The inhibition of histone deacetylase 8 suppresses proliferation and inhibits apoptosis in gastric adenocarcinoma.

    PubMed

    Song, Shiyuan; Wang, Ying; Xu, Po; Yang, Ruina; Ma, Zhikun; Liang, Shuo; Zhang, Guangping

    2015-11-01

    Histone deacetylase 8 (HDAC8), a unique member of class I HDACs, shows remarkable correlation with advanced disease stage. The depletion of HDAC8 leads to inhibition of proliferation, apoptosis and cell cycle arrest in multiple malignant tumors. However, little is known about the contribution of HDAC8 to the tumorigenesis of gastric cancer (GC). The present study investigated expression of HDAC8 in GC cell lines and tissues, and the roles of HDAC8 inhibition in the proliferation, cell cycle and apoptosis of gastric cancer cells and explored the potential mechanisms. In the present study, quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR), western blotting, and immunohistochemistry were used to examine the mRNA and protein expression of HDAC8 in GC cell lines and tissues. Then, the correlation between the clinicopathological parameters and the expression of HDAC8 was assessed. Finally, siRNA transfection and HDAC8 plasmid was performed to explore the functions of HDAC8 in GC progression in vitro. We found that the expression of HDAC8 was significantly upregulated both in GC cell lines and tumor tissues compared to human normal gastric epithelial cell, GES-1 and matched non-tumor tissues. Furthermore, depletion of HDAC8 remarkably inhibited GC cell proliferation, increased the apoptosis rate and G0/G1 phase percentage in vitro. Western blotting showed that the expression of protein promoting apoptosis such as, Bmf, activated caspase-3, caspase-6 were elevated following HDAC8 depletion. Our data exhibited an important role of HDAC8 in promoting gastric cancer tumorigenesis and identify this HDAC8 as a potential therapeutic target for the treatment of gastric cancer. PMID:26412386

  14. Vitamin D inhibition of lung adenocarcinoma cell proliferation in vitro.

    PubMed

    Li, Rong; Lou, Yuqing; Zhang, Weiyan; Dong, Qianggang; Han, Baohui

    2014-11-01

    Vitamin D has the capability to inhibit tumor cell proliferation and promote tumor cell apoptosis but whether this mechanism exists in lung adenocarcinoma cells remains to be studied. Our objective is to explore whether vitamin D has the capability to inhibit lung adenocarcinoma cell proliferation and synergize with cisplatin. Our method was to explore the effect of different concentrations of 1,25(OH)2D3 with or without cisplatin on lung adenocarcinoma cells by detecting cell proliferation rates at different time points. 1,25(OH)2D3 was capsulated with nanomaterial before acting on lung adenocarcinoma cells, and cell proliferation rates at different time points were detected with the CCK-8 method. When vitamin D was applied at a concentration of 1 × 10(-7) and 1 × 10(-6) mol/L on A549, PC9, SPC-A1, and H1650 cells for 72 h, no inhibition occurred on cell proliferation. Between the concentrations of 1 × 10(-5) and 0.5 × 10(-5) mol/L, inhibition on cell proliferation increased with drug action time. Between the concentration of 2.5 × 10(-5) and 0.03 × 10(-5) mol/L, inhibition on cell proliferation increased with increasing drug concentration. Analysis using bivariate correlations showed that the correlation coefficient of the proliferation inhibition rate and drug content was 0.580 (p < 0.0001). The correlation coefficient of proliferation inhibition rate and the drug action time was 0.379 (p = 0.01). The combined use of vitamin D and dichlorodiammine-platinum(II) (DDP) significantly increased the inhibition rate on A549 cell proliferation, which peaked after culturing for 96 h (Table 4). Further analysis using bivariate correlations showed that the correlation coefficient between proliferation inhibition rate and DDP concentration was 0.319 (p < 0.0001). The correlation coefficient of the proliferation inhibition rate and vitamin D concentration was 0.269 (p < 0.0001). The correlation coefficient of proliferation inhibition and drug action time was 0.221(p

  15. SIRT1 inhibits the mouse intestinal motility and epithelial proliferation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    SIRT1 inhibits the mouse intestinal motility and epithelial proliferation. Sirtuin 1 (SIRT1), a NAD+-dependent histone deacetylase, is involved in a wide array of cellular processes, including glucose homeostasis, energy metabolism, proliferation and apoptosis, and immune response. However, it is un...

  16. Effect of A-63162 on lymphocyte proliferation, IL-2 production, mRNA for Il-2 and LTB sub 4 production from human mononuclear cells

    SciTech Connect

    Atluru, D.; Atluru, S. ); Woloschak, G.E. )

    1991-03-15

    Lipoxygenase metabolites of arachidonic acid have diversified effects on human lymphocytes. In the present investigation, the authors measured the effects of A-63162, a specific 5-lipoxygenase inhibitor on lymphocyte proliferation, IL-2 production, mRNA for IL-2 and LTB{sub 4} synthesis from peripheral blood human mononuclear cells. A-63162 inhibited the {sup 3}H-thymidine incorporation from PHA or PMA plus A23187 stimulated cultures. The synthesis of IL-2 was also inhibited from PHA plus PMA or PMA plus A23187 stimulated cultures. Further, they found A-63162 also inhibited the accumulation of IL-2 mRNA. And, A-63162 at that above concentration also inhibited the LTB{sub 4} synthesis from A23187 stimulated cultures. The results suggest that endogenous LTB{sub 4} may play an important role in regulating IL-2 production at the message level.

  17. Blue light inhibits proliferation of melanoma cells

    NASA Astrophysics Data System (ADS)

    Becker, Anja; Distler, Elisabeth; Klapczynski, Anna; Arpino, Fabiola; Kuch, Natalia; Simon-Keller, Katja; Sticht, Carsten; van Abeelen, Frank A.; Gretz, Norbert; Oversluizen, Gerrit

    2016-03-01

    Photobiomodulation with blue light is used for several treatment paradigms such as neonatal jaundice, psoriasis and back pain. However, little is known about possible side effects concerning melanoma cells in the skin. The aim of this study was to assess the safety of blue LED irradiation with respect to proliferation of melanoma cells. For that purpose we used the human malignant melanoma cell line SK-MEL28. Cell proliferation was decreased in blue light irradiated cells where the effect size depended on light irradiation dosage. Furthermore, with a repeated irradiation of the melanoma cells on two consecutive days the effect could be intensified. Fluorescence-activated cell sorting with Annexin V and Propidium iodide labeling did not show a higher number of dead cells after blue light irradiation compared to non-irradiated cells. Gene expression analysis revealed down-regulated genes in pathways connected to anti-inflammatory response, like B cell signaling and phagosome. Most prominent pathways with up-regulation of genes were cytochrome P450, steroid hormone biosynthesis. Furthermore, even though cells showed a decrease in proliferation, genes connected to the cell cycle were up-regulated after 24h. This result is concordant with XTT test 48h after irradiation, where irradiated cells showed the same proliferation as the no light negative control. In summary, proliferation of melanoma cells can be decreased using blue light irradiation. Nevertheless, the gene expression analysis has to be further evaluated and more studies, such as in-vivo experiments, are warranted to further assess the safety of blue light treatment.

  18. Stabilization of tubulin mRNA by inhibition of protein synthesis in sea urchin embryos.

    PubMed Central

    Gong, Z Y; Brandhorst, B P

    1988-01-01

    An increased level of unpolymerized tubulin caused by depolymerization of microtubules in sea urchin larvae resulted in a rapid loss of tubulin mRNA, which was prevented by nearly complete inhibition of protein synthesis. Results of an RNA run-on assay indicated that inhibition of protein synthesis does not alter tubulin gene transcription. Analysis of the decay of tubulin mRNA in embryos in which RNA synthesis was inhibited by actinomycin D indicated that inhibition of protein synthesis prevents the destabilization of tubulin mRNA. The effect was similar whether mRNA was maintained on polysomes in the presence of emetine or anisomycin or displaced from the polysomes in the presence of puromycin or pactamycin; thus, the stabilization of tubulin mRNA is not dependent on the state of the polysomes after inhibition of protein synthesis. Even after tubulin mRNA declined to a low level after depolymerization of microtubules, it could be rescued by treatment of embryos with inhibitors of protein synthesis. Tubulin mRNA could be induced to accumulate prematurely in gastrulae but not in plutei if protein synthesis was inhibited, an observation that is indicative of the importance of the autogenous regulation of tubulin mRNA stability during embryogenesis. Possible explanations for the role of protein synthesis in the control of mRNA stability are discussed. Images PMID:3211150

  19. Mitophagy inhibits proliferation by decreasing cyclooxygenase-2 (COX-2) in arsenic trioxide-treated HepG2 cells.

    PubMed

    Niu, Zhidan; Zhang, Wenya; Gu, Xueyan; Zhang, Xiaoning; Qi, Yongmei; Zhang, Yingmei

    2016-07-01

    Mitochondrial damage can trigger mitophagy and eventually suppress proliferation. However, the effect of mitophagy on proliferation remains unclear. In this study, HepG2 cells were used to assess mitophagy and proliferation arrest in response to As2O3 exposure. The stimulatory effect of As2O3 on mitophagy was investigated by assessing morphology (mitophagosome and mitolysosome) and relevant proteins (PINK1, LC3 II/I, and COX IV). Additionally, the relationship of mitophagy and proliferation was explored through the use of mitophagy inhibitors (CsA, Mdivi-1). Interestingly, the inhibition of mitophagy rescued proliferation arrest by restoring COX-2 protein level and countered the elimination of mitochondria-located COX-2 and up-regulated the COX-2 mRNA level. Taken together, our findings indicated that mitophagy can be induced and can inhibit proliferation by reducing COX-2 in HepG2 cells during As2O3 treatment. PMID:27318970

  20. MiR-520b suppresses proliferation of hepatoma cells through targeting ten-eleven translocation 1 (TET1) mRNA

    SciTech Connect

    Zhang, Weiying; Lu, Zhanping; Gao, Yuen; Ye, Lihong; Song, Tianqiang; Zhang, Xiaodong

    2015-05-08

    Accumulating evidence indicates that microRNAs are able to act as oncogenes or tumor suppressor genes in human cancer. We previously reported that miR-520b was down-regulated in hepatocellular carcinoma (HCC) and its deregulation was involved in hepatocarcinogenesis. In the present study, we report that miR-520b suppresses cell proliferation in HCC through targeting the ten-eleven translocation 1 (TET1) mRNA. Notably, we identified that miR-520b was able to target 3′-untranslated region (3′UTR) of TET1 mRNA by luciferase reporter gene assays. Then, we revealed that miR-520b was able to reduce the expression of TET1 at the levels of mRNA and protein using reverse transcription-polymerase chain reaction and Western blotting analysis. In terms of function, 5-ethynyl-2-deoxyuridine (EdU) incorporation and colony formation assays demonstrated that the forced miR-520b expression remarkably inhibited proliferation of hepatoma cells, but TET1 overexpression could rescue the inhibition of cell proliferation mediated by miR-520b. Furthermore, anti-miR-520b enhanced proliferation of hepatoma cells, whereas silencing of TET1 abolished anti-miR-520b-induced acceleration of cell proliferation. Then, we validated that the expression levels of miR-520b were negatively related to those of TET1 mRNA in clinical HCC tissues. Thus, we conclude that miR-520b depresses proliferation of liver cancer cells through targeting 3′UTR of TET1 mRNA. Our finding provides new insights into the mechanism of hepatocarcinogenesis. - Highlights: • TET1 is a novel target gene of miR-520b. • TET1 is upregulated in clinical HCC tissues. • MiR-520b is negatively correlated with TET1 in clinical HCC tissues. • MiR-520b depresses the proliferation of HCC cells through targeting TET1 mRNA.

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

    SciTech Connect

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

    2013-11-01

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

  2. Cell proliferation inhibition in reduced gravity

    NASA Technical Reports Server (NTRS)

    Moos, P. J.; Fattaey, H. K.; Johnson, T. C.; Spooner, B. S. (Principal Investigator)

    1994-01-01

    Extended durations of spaceflight have been shown to be deleterious on an organismic level; however, mechanisms underlying cellular sensitivity to the gravitational environment remain to be elucidated. The majority of the gravitational studies to date indicates that cell regulatory pathways may be influenced by their gravitational environment. Still, few cell biology experiments have been performed in space flight and even fewer experiments have been repeated on subsequent flights. With flight opportunities on STS-50, 54, and 57, Sf9 cells were flown in the BioServe Fluids Processing Apparatus and cell proliferation was measured with and without exposure to a cell regulatory sialoglycopeptide (CeReS) inhibitor. Results from these flights indicate that the Sf9 cells grew comparable to ground controls, that the CeReS inhibitor bound to its specific receptor, and that its signal transduction cascade was not gravity sensitive.

  3. Calcitriol Inhibits Cervical Cancer Cell Proliferation Through Downregulation of HCCR1 Expression.

    PubMed

    Wang, Guoqing; Lei, Lei; Zhao, Xixia; Zhang, Jun; Zhou, Min; Nan, Kejun

    2014-01-01

    Calcitriol (1α,25-dihydroxyvitamin D3) has demonstrated anticancer activity against several tumors. However, the underlying mechanism for this activity is not yet fully understood. Our experiment was designed and performed to address one aspect of this issue in cervical cancer. HeLa S3 cells were cultured in media with various concentrations of calcitriol. Cell proliferation and cell cycle were assessed by spectrophotometry and flow cytometry, respectively. The mRNA and protein expression levels of human cervical cancer oncogene (HCCR-1) and p21 were determined by RT-PCR and Western blot, respectively. Results indicated that calcitriol inhibited HeLa S3 cell proliferation and induced cell cycle arrest at the G1 phase. Calcitriol decreased HCCR-1 protein expression in a dose- and time-dependent manner. Furthermore, promoter activity analyses revealed that transcriptional regulation was involved in the inhibition of HCCR-1 expression. Overexpression of HCCR-1 in HeLa S3 cells reversed the inhibition of cell proliferation and G1 phase arrest that resulted from calcitriol treatment. In addition, calcitriol increased p21 expression and promoter activity. HCCR-1 overexpression decreased p21 expression and promoter activity. Thus, our results suggested that calcitriol inhibited HeLa S3 cell proliferation by decreasing HCCR-1 expression and increasing p21 expression. PMID:26629942

  4. CPEB1 restrains proliferation of Glioblastoma cells through the regulation of p27Kip1 mRNA translation

    PubMed Central

    Galardi, Silvia; Petretich, Massimo; Pinna, Guillaume; D’Amico, Silvia; Loreni, Fabrizio; Michienzi, Alessandro; Groisman, Irina; Ciafrè, Silvia Anna

    2016-01-01

    The cytoplasmic element binding protein 1 (CPEB1) regulates many important biological processes ranging from cell cycle control to learning and memory formation, by controlling mRNA translation efficiency via 3′ untranslated regions (3′UTR). In the present study, we show that CPEB1 is significantly downregulated in human Glioblastoma Multiforme (GBM) tissues and that the restoration of its expression impairs glioma cell lines growth. We demonstrate that CPEB1 promotes the expression of the cell cycle inhibitor p27Kip1 by specifically targeting its 3′UTR, and competes with miR-221/222 binding at an overlapping site in the 3′UTR, thus impairing miR-221/222 inhibitory activity. Upon binding to p27Kip1 3′UTR, CPEB1 promotes elongation of poly-A tail and the subsequent translation of p27Kip1 mRNA. This leads to higher levels of p27Kip1 in the cell, in turn significantly inhibiting cell proliferation, and confers to CPEB1 a potential value as a tumor suppressor in Glioblastoma. PMID:27142352

  5. CPEB1 restrains proliferation of Glioblastoma cells through the regulation of p27(Kip1) mRNA translation.

    PubMed

    Galardi, Silvia; Petretich, Massimo; Pinna, Guillaume; D'Amico, Silvia; Loreni, Fabrizio; Michienzi, Alessandro; Groisman, Irina; Ciafrè, Silvia Anna

    2016-01-01

    The cytoplasmic element binding protein 1 (CPEB1) regulates many important biological processes ranging from cell cycle control to learning and memory formation, by controlling mRNA translation efficiency via 3' untranslated regions (3'UTR). In the present study, we show that CPEB1 is significantly downregulated in human Glioblastoma Multiforme (GBM) tissues and that the restoration of its expression impairs glioma cell lines growth. We demonstrate that CPEB1 promotes the expression of the cell cycle inhibitor p27(Kip1) by specifically targeting its 3'UTR, and competes with miR-221/222 binding at an overlapping site in the 3'UTR, thus impairing miR-221/222 inhibitory activity. Upon binding to p27(Kip1) 3'UTR, CPEB1 promotes elongation of poly-A tail and the subsequent translation of p27(Kip1) mRNA. This leads to higher levels of p27(Kip1) in the cell, in turn significantly inhibiting cell proliferation, and confers to CPEB1 a potential value as a tumor suppressor in Glioblastoma. PMID:27142352

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

    SciTech Connect

    Jeong, Hyesun; Oh, Seung-ick; Hong, Sunghoi E-mail: radioyoon@korea.ac.kr; Sung, Jiwon; Jeong, Seonghoon; Yoon, Myonggeun E-mail: radioyoon@korea.ac.kr; Koh, Eui Kwan

    2014-11-17

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

  7. Expression of the mRNA encoding truncated PPAR alpha does not correlate with hepatic insensitivity to peroxisome proliferators.

    PubMed

    Hanselman, J C; Vartanian, M A; Koester, B P; Gray, S A; Essenburg, A D; Rea, T J; Bisgaier, C L; Pape, M E

    2001-01-01

    Two alternatively spliced forms of human PPAR alpha mRNA, PPAR alpha1 and PPAR alpha2, have been identified. PPAR alpha1 mRNA gives rise to an active PPAR alpha protein while PPAR alpha2 mRNA gives rise to a form of PPAR which lacks the ligand-binding domain. PPAR alpha2 is unable to activate a peroxisome proliferator response element (PPRE) reporter gene construct in transient transfection assays. Both PPAR alpha1 and PPAR alpha2 mRNA are present in human liver, kidney, testes, heart, small intestine, and smooth muscle. In human liver, PPAR alpha2 mRNA abundance is approximately half that of PPAR alpha1 mRNA; a correlation analysis of PPAR alpha1 and PPAR alpha2 mRNA mass revealed an r-value of 0.75 (n = 18). Additional studies with intact liver from various species, showed that the PPAR alpha2/PPAR alpha1 mRNA ratios in rat, rabbit, and mouse liver were less than 0.10; significantly lower than the 0.3 and 0.5 ratios observed in monkey and human livers, respectively. To determine if a high PPAR alpha2/PPAR alpha1 mRNA ratio was associated with insensitivity to peroxisome proliferators, we treated human, rat, and rabbit hepatocytes with WY14643, a potent PPAR alpha activator, and measured acyl CoA oxidase (ACO) mRNA levels. Rat ACO mRNA levels increased markedly in response to WY14643 while human and rabbit hepatocytes were unresponsive. Thus, although the PPAR alpha2/PPAR alpha1 mRNA ratio is low in rabbits, this species is not responsive to peroxisome proliferators. Further studies with male and female rats, which vary significantly in their response to peroxisome proliferators, showed little difference in the ratio of PPAR alpha2/PPAR alpha1 mRNA. These data suggest that selective PPAR alpha2 mRNA expression is not the basis for differential species or gender responses to peroxisome proliferators. PMID:11269670

  8. SIRT1 controls cell proliferation by regulating contact inhibition.

    PubMed

    Cho, Elizabeth H; Dai, Yan

    2016-09-16

    Contact inhibition keeps cell proliferation in check and serves as a built-in protection against cancer development by arresting cell division upon cell-cell contact. Yet the complete mechanism behind this anti-cancer process remains largely unclear. Here we present SIRT1 as a novel regulator of contact inhibition. SIRT1 performs a wide variety of functions in biological processes, but its involvement in contact inhibition has not been explored to date. We used NIH3T3 cells, which are sensitive to contact inhibition, and H460 and DU145 cancer cells, which lack contact inhibition, to investigate the relationship between SIRT1 and contact inhibition. We show that SIRT1 overexpression in NIH3T3 cells overcomes contact inhibition while SIRT1 knockdown in cancer cells restores their lost contact inhibition. Moreover, we demonstrate that p27 protein expression is controlled by SIRT1 in contact inhibition. Overall, our findings underline the critical role of SIRT1 in contact inhibition and suggest SIRT1 inhibition as a potential strategy to suppress cancer cell growth by restoring contact inhibition. PMID:27514448

  9. ALA-PDT inhibits proliferation and promotes apoptosis of SCC cells through STAT3 signal pathway.

    PubMed

    Qiao, Li; Mei, Zhusong; Yang, Zhiyong; Li, Xinji; Cai, Hong; Liu, Wei

    2016-06-01

    Previous studies suggest that apoptosis of carcinoma cells led by photodynamics is mainly intrinsic apoptosis, but whether the extrinsic pathway is involved in the treatment of carcinoma by photodynamic therapy is not confirmed. This research investigated the effect of ALA-PDT on the proliferation and apoptosis of SCC cell A431 and COLO-16, and discussed the role played by JAK/STAT3 signal pathway in this process. Our data showed that the expression levels STAT3 and p-STAT3 protein in the cancer tissue are higher than the corresponding adjacent tissue to carcinoma. The expression level of p-STAT3 in cancerous tissue has a correlation with the tumor size and tissue histopathological differentiation. ALA-PDT could inhibit proliferation of A431 and COLO-16 cells, STAT3 knock down could enhance ALA-PDT's inhibition of cell proliferation, and promote apoptosis induced by ALA-PDT. On the other hand, overexpression of STAT3 has the opposite effect. In addition, ALA-PDT can weaken the protein expression of STAT3 and its target gene Bcl-2 mRNA, and ALA-PDT can strengthen the protein expression of STAT3's target gene Bax mRNA. Overexpression of STAT3 can offset the effect on Bcl-2 and Bax by ALA-PDT; on the other hand, STAT3 knocking down can strengthen ALA-PDT's effect on Bcl-2 and Bax. PMID:26805005

  10. [Emodin inhibits the proliferation, transdifferentiation and collagen synthesis of pulmonary fibroblasts].

    PubMed

    Liu, Lijing; Yin, Huiming; He, Jianbin; Xie, Maofeng; Wang, Zaiyan; Xiao, Hua

    2016-07-01

    Objective To explore the effect of emodin on the proliferation, differentiation into myofibroblasts and collagen synthesis of pulmonary fibroblasts and the underlying mechanisms. Methods Human pulmonary fibroblasts MRC-5 were cultured in vitro, then the cells were inoculated with dimethyl sulfoxide (DMSO) added with 0, 10, 20, 40, 80 and 160 μmol/L emodin for 24, 48 and 72 hours. Inhibitory rate of cell proliferation was analyzed by MTT assay. Based on the results of cell proliferation experiment, MRC-5 cells were treated with DMSO (control group) and 40, 80 μmol/L emodin (in DMSO) for 48 hours. Fluorescence real-time quantitative PCR was then used to measure the mRNA expressions of α-smooth muscle actin (α-SMA), transforming growth factor-β1 (TGF-β1), a disintegrin-like and metalloproteinase with thrombospondin type 1 motif (ADAMTS-1), collagen type 1 (Col1) and collagen type 3 (Col3). The protein expressions of the above mentioned factors were also measured by Western blotting. Results In a concentration- and time-dependent manner, emodin inhibited MRC-5 cell proliferation. After 48 hours of co-culture, in comparison with control group, the mRNA and protein expression levels of α-SMA, TGF-β1, Col1 and Col3 significantly decreased, while the mRNA and protein expression levels of ADAMTS-1 significantly increased in 40 and 80 μmol/L emodin-treated groups. Moreover, in comparison with 40 μmol/L emodin-treated group, the mRNA and protein expressions of α-SMA, TGF-β1, Col1 and Col3 were significantly downregulated, but ADAMTS-1 mRNA and protein expressions were significantly upregulated in 80 μmol/L emodin-treated group. Conclusion Emodin can block pulmonary fibroblast proliferation and differentiation into myofibroblasts, and reduce the synthesis of Col1 and Col3 by inhibiting TGF-β1/ADAMTS-1 signaling pathway. PMID:27363273

  11. The Oncogene LRF Stimulates Proliferation of Mesenchymal Stem Cells and Inhibits Their Chondrogenic Differentiation

    PubMed Central

    Li, Huan; Acharya, Chitrangada; Kumari, Ratna; Fierro, Fernando; Haudenschild, Dominik R.; Nolta, Jan; Di Cesare, Paul E.

    2013-01-01

    Objective. The oncogene leukemia/lymphoma-related factor (LRF) enhances chondrosarcoma proliferation and malignancy. This study aimed to investigate the roles of LRF in chondrogenic differentiation of primary human bone marrow–derived mesenchymal stem cells (BMSCs). Design. LRF was overexpressed in BMSC by lentiviral transduction. Chondrogenic differentiation of BMSC was induced by high-density pellet culture. Western blotting and real-time polymerase chain reaction were used to investigate changes in protein and mRNA levels, respectively, during chondrogenesis. Safranin-O staining, immunohistochemistry, and glycoaminoglycan contents were used to assess cartilage matrix deposition. BMSC proliferation was determined by mitochondrial dehydrogenase activity and cell counting. Cell cycle profiling was performed by flow cytometry. Results. LRF overexpression effectively inhibited protein and mRNA expression of chondrocyte markers and cartilage matrix deposition during chondrogenesis of BMSC. Endogenous LRF expression was constitutively high in undifferentiated BMSC but remained low in primary articular chondrocytes. Endogenous LRF protein was downregulated in a time-dependent manner during chondrogenesis. BMSCs overexpressing LRF had higher proliferation rates and cell population in the S phase. LRF suppressed p53 expression during chondrogenesis and this might prevent differentiating chondrocytes from entering a quiescent state. Conclusion. Our data showed that LRF is important for stimulating stem cell proliferation and cell cycle progression. It is known that LRF is highly expressed in the mouse limb buds prior to overt chondrogenesis; thus, LRF might function to prevent premature chondrogenic differentiation of stem cells. PMID:26069677

  12. Crocin inhibits cell proliferation and enhances cisplatin and pemetrexed chemosensitivity in lung cancer cells

    PubMed Central

    Chen, Shuangshuang; Zhao, Shuang; Wang, Xinxing; Zhang, Luo; Jiang, Enze; Gu, Yuan; Shangguan, Anna Junjie; Zhao, Hong

    2015-01-01

    Background Crocin is the major constituent of saffron, a naturally derived Chinese medicine obtained from the dried stigma of the Crocus sativus flower. It has a variety of pharmacological effects, including anti-oxidative, immunity enhancement, and anti-tumorigenic properties; however, the molecular mechanisms underlying these effects remain unknown. Methods To investigate the effects of crocin on proliferation and apoptosis of lung adenocarcinoma cells, lung adenocarcinoma cell lines, A549 and SPC-A1, were treated with crocin at different dosages. Cell morphological changes were observed by light microscopy. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was performed to detect the inhibitory effect of crocin on cell proliferation and sensitivity to chemotherapeutic drugs. Flow cytometry was used to characterize cell apoptosis and cell cycle profiles. Reverse transcription-polymerase chain reaction was used to detect mRNA levels of apoptosis-related genes. Results Crocin inhibited cell proliferation and induced apoptosis in A549 and SPC-A1 cells in a concentration-dependent manner, accompanied with an increase of G0/G1 arrest. Crocin significantly increased the mRNA levels of both p53 and B-cell lymphoma 2-associated X protein (Bax), while decreasing B-cell lymphoma 2 (Bcl-2) mRNA expressions. In addition, crocin combined with either cisplatin or pemetrexed showed additive effects on cell proliferation in two lung cancer cell lines. Conclusions Crocin significantly suppressed the proliferation of human lung adenocarcinoma cells and enhanced the chemo sensitivity of these cells to both cisplatin and pemetrexed. The actions of molecular mechanism could be through the induction of cell cycle arrest and apoptosis by p53 and Bax up-regulation but Bcl-2 down-regulation. PMID:26798587

  13. Inhibition of cyclooxygenase (COX)-2 affects endothelial progenitor cell proliferation

    SciTech Connect

    Colleselli, Daniela; Bijuklic, Klaudija; Mosheimer, Birgit A.; Kaehler, Christian M. . E-mail: C.M.Kaehler@uibk.ac.at

    2006-09-10

    Growing evidence indicates that inducible cyclooxygenase-2 (COX-2) is involved in the pathogenesis of inflammatory disorders and various types of cancer. Endothelial progenitor cells recruited from the bone marrow have been shown to be involved in the formation of new vessels in malignancies and discussed for being a key point in tumour progression and metastasis. However, until now, nothing is known about an interaction between COX and endothelial progenitor cells (EPC). Expression of COX-1 and COX-2 was detected by semiquantitative RT-PCR and Western blot. Proliferation kinetics, cell cycle distribution and rate of apoptosis were analysed by MTT test and FACS analysis. Further analyses revealed an implication of Akt phosphorylation and caspase-3 activation. Both COX-1 and COX-2 expression can be found in bone-marrow-derived endothelial progenitor cells in vitro. COX-2 inhibition leads to a significant reduction in proliferation of endothelial progenitor cells by an increase in apoptosis and cell cycle arrest. COX-2 inhibition leads further to an increased cleavage of caspase-3 protein and inversely to inhibition of Akt activation. Highly proliferating endothelial progenitor cells can be targeted by selective COX-2 inhibition in vitro. These results indicate that upcoming therapy strategies in cancer patients targeting COX-2 may be effective in inhibiting tumour vasculogenesis as well as angiogenic processes.

  14. Hydroxyflavanone inhibits gastric carcinoma MGC-803 cell proliferation

    PubMed Central

    Zhang, Haiyan; Zhan, Zhuo; Cui, Mingfu; Gao, Yongjian; Wang, Dayu; Feng, Ye

    2015-01-01

    Gastric carcinoma (GC) is the most common primary malignancy of the digestive tract, with increasing incidence in many countries. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to assess inhibition of HepG2 cell proliferation by 2’-hydroxyflavanone. The STAT3 pathway was performed. 2’-hydroxyflavanone reduced inhibitory effects on MGC-803 cell proliferation. 2’-hydroxyflavanone exhibited the highest inhibition rate. Treatment of MGC-803 cells with 400, 200, and 100 μg/ml 2’-hydroxyflavanone resulted in 88.9±0.7%, 81.2±0.5%, 68.4±0.5% decrease in cell viability, respectively, indicating an IC50 of 9.3 μg/ml. The 100 μg/ml 2’-hydroxyflavanone can significantly inhibit the STAT3 pathway activation. 2’-hydroxyflavanone inhibits MGC-803 cell proliferation by inhibiting STAT3 pathway activation. This extract is therefore a potential drug candidate for treatment of liver cancer. PMID:26629250

  15. Pirfenidone inhibits migration, differentiation, and proliferation of human retinal pigment epithelial cells in vitro

    PubMed Central

    Wang, Jing; Yang, Yangfan; Xu, Jiangang; Lin, Xianchai; Wu, Kaili

    2013-01-01

    Purpose To investigate the effects of pirfenidone (PFD) on the migration, differentiation, and proliferation of retinal pigment epithelial (RPE) cells and demonstrate whether the drug induces cytotoxicity. Methods Human RPE cells (line D407) were treated with various concentrations of PFD. Cell migration was measured with scratch assay. The protein levels of fibronectin (FN), connective tissue growth factor (CTGF), α-smooth muscle actin (α-SMA), transforming growth factor beta (TGFβS), and Smads were assessed with western blot analyses. Levels of mRNA of TGFβS, FN, and Snail1 were analyzed using reverse transcriptase–polymerase chain reaction. Cell apoptosis was detected with flow cytometry using the Annexin V/PI apoptosis kit, and the percentages of cells labeled in different apoptotic stage were compared. A Trypan Blue assay was used to assess cell viability. Results PFD inhibited RPE cell migration. Western blot analyses showed that PFD inhibited the expression of FN, α-SMA, CTGF, TGFβ1, TGFβ2, Smad2/3, and Smad4. Similarly, PFD also downregulated mRNA levels of Snail1, FN, TGFβ1, and TGFβ2. No significant differences in cell apoptosis or viability were observed between the control and PFD-treated groups. Conclusions PFD inhibited RPE cell migration, differentiation, and proliferation in vitro and caused no significant cytotoxicity. PMID:24415895

  16. Ethylene Inhibits Cell Proliferation of the Arabidopsis Root Meristem.

    PubMed

    Street, Ian H; Aman, Sitwat; Zubo, Yan; Ramzan, Aleena; Wang, Xiaomin; Shakeel, Samina N; Kieber, Joseph J; Schaller, G Eric

    2015-09-01

    The root system of plants plays a critical role in plant growth and survival, with root growth being dependent on both cell proliferation and cell elongation. Multiple phytohormones interact to control root growth, including ethylene, which is primarily known for its role in controlling root cell elongation. We find that ethylene also negatively regulates cell proliferation at the root meristem of Arabidopsis (Arabidopsis thaliana). Genetic analysis indicates that the inhibition of cell proliferation involves two pathways operating downstream of the ethylene receptors. The major pathway is the canonical ethylene signal transduction pathway that incorporates CONSTITUTIVE TRIPLE RESPONSE1, ETHYLENE INSENSITIVE2, and the ETHYLENE INSENSITIVE3 family of transcription factors. The secondary pathway is a phosphorelay based on genetic analysis of receptor histidine kinase activity and mutants involving the type B response regulators. Analysis of ethylene-dependent gene expression and genetic analysis supports SHORT HYPOCOTYL2, a repressor of auxin signaling, as one mediator of the ethylene response and furthermore, indicates that SHORT HYPOCOTYL2 is a point of convergence for both ethylene and cytokinin in negatively regulating cell proliferation. Additional analysis indicates that ethylene signaling contributes but is not required for cytokinin to inhibit activity of the root meristem. These results identify key elements, along with points of cross talk with cytokinin and auxin, by which ethylene negatively regulates cell proliferation at the root apical meristem. PMID:26149574

  17. MicroRNA-29a inhibits mesenchymal stem cell viability and proliferation by targeting Roundabout 1.

    PubMed

    Zhang, Yudong; Zhou, Shenghua

    2015-10-01

    Secreted Slit glycoproteins and their Roundabout (Robo) receptors have been identified as important axon guidance molecules. The pivotal role of Slit‑Robo signaling is in regulating cell proliferation. MicroRNAs (miRNAs), a class of small non‑coding RNAs, function as critical regulators of gene expression by binding to the 3'‑untranslated region of mRNAs and causing mRNA degradation or translational repression. The present study demonstrated that downregulation of Robo1 using small interfering RNA inhibited mesenchymal stem cell (MSC) proliferation. Additionally, four miRNAs (miR), including miR‑218, miR‑29a, miR‑146 and miR‑148, inhibited the protein expression of Robo1 in the MSCs, with miR‑29 having the most marked effect. A luciferase reporter assay identified Robo1 as a novel target of miR‑29a. Overexpression of miR‑29a suppressed the protein expression levels of Robo1 and Slit2 and inhibited the viability and proliferation of the MSCs. By contrast, overexpression of Robo1 partly rescued these inhibitory effects of miR‑29a on the MSCs confirming that miR‑29a inhibited MSC viability and proliferation, at least partially, by directly targeting Robo1. These results indicated that the miR‑29a/Robo1 axis is crucial for the regulation of MSC viability and proliferation, suggesting that miR‑29a may serve as a potential clinical target for MSC expansion and stem cell transplantation. PMID:26252416

  18. Metformin inhibits the proliferation of A431 cells by modulating the PI3K/Akt signaling pathway

    PubMed Central

    LIU, YINGSHAN; ZHANG, YAN; JIA, KUN; DONG, YUHAO; MA, WEIYUAN

    2015-01-01

    The ability of metformin, an antidiabetic drug with wide applications, to inhibit tumor cell growth has recently been discovered. The PI3K/Akt signaling pathway has been found to play an important role in the survival, proliferation and apoptosis of tumor cells. The aim of the present study was to explore the effect of metformin on the proliferation of A431 human squamous cell carcinoma cells and the underlying molecular mechanisms. A431 cells in the logarithmic growth phase were treated with 0, 15, 30, 45 and 60 mM metformin for 12, 24 and 36 h, respectively. Cell morphology with 45 mM metformin treatment for 24 h was observed under a microscope. The proliferation of A431 cells was detected by the Cell Counting kit-8 colorimetric method. The mRNA expression levels of PI3K and Akt were detected by reverse transcription-polymerase chain reaction (RT-PCR). The protein expression levels of PI3K, Akt and phosphorylated (p)-Akt were detected by western blot analysis. Metformin treatment caused morphological change in A431 cells and inhibited their proliferation in a significant time- and dose-dependent manner. RT-PCR results showed that the mRNA expression of PI3K was inhibited by metformin in a time- and dose-dependent manner (P<0.05). However, there was no significant change in the mRNA expression of Akt following metformin treatment (P>0.05). Western blotting results showed that the protein expression levels of PI3K and p-Akt were inhibited by metformin in a time- and dose-dependent manner (P<0.05). In conclusion, metformin significantly inhibited the proliferation of A431 cells in the current study, which may be strongly associated with the inhibition of the PI3K/Akt signaling pathway. PMID:25780442

  19. Sesquiterpenoid Lactones in Tanacetum huronense Inhibit Human Glioblastoma Cell Proliferation.

    PubMed

    Dissanayake, Amila A; Bejcek, Bruce E; Zhang, Chuan-Rui; Nair, Muraleedharan G

    2016-05-01

    Tanacetum huronense (Lake Huron tansy), which is native to the upper Midwest region of USA and Canada, was examined for the presence of anticancer compounds using an in vitro human tumor cell proliferation inhibition assay, with glioblastoma derived cell line U-87 MG. Bioassay-directed purification of the ethyl acetate extract of the aerial portion of this plant identified six active sesquiterpenoid lactones (1-6). Among these, compounds 5 and 6 are new structural analogs. One of the most abundant isolates, tanacin (4), exhibited the greatest inhibition with an IC50 value of 4.5 μg/mL. PMID:27319121

  20. Fangchinoline inhibits breast adenocarcinoma proliferation by inducing apoptosis.

    PubMed

    Xing, Zhi-Bo; Yao, Lei; Zhang, Guo-Qiang; Zhang, Xian-Yu; Zhang, You-Xue; Pang, Da

    2011-01-01

    Radix Stephaniae tetrandrae, which contains tetrandrine (Tet) and fangchinoline, is traditionally used as an analgesic, antirheumatic, and antihypertensive drug in China. In this study, we investigated its effect on breast cancer cell proliferation and its potential mechanism of action in vitro. Treatment of cells with fangchinoline significantly inhibited MDA-MB-231 cell proliferation in a concentration- and time-dependent manner. To define the mechanism underlying the antiproliferative effects of fangchinoline, we studied its effects on critical molecular events known to regulate the apoptotic machinery. Specifically, we addressed the potential of fangchinoline to induce apoptosis of breast cancer cells. Fangchinoline induced internucleosomal DNA fragmentation, chromatin condensation, activation of caspases-3, -8, and -9, and cleavage of poly(ADP ribose) polymerase, as well as enhanced mitochondrial cytochrome c release. Furthermore, fangchinoline increased the expression of the proapoptotic protein B cell lymphoma-2 associated X (Bax) and decreased the expression of the antiapoptotic protein B cell lymphoma-2 (Bcl-2). In addition, the proliferation-inhibitory effect of fangchinoline was associated with decreased levels of phosphorylated Akt. Our results indicate that fangchinoline can inhibit breast cancer cell proliferation by inducing apoptosis via the mitochondrial apoptotic pathway and decreasing phosphorylated Akt. Thus fangchinoline may be a novel agent that can potentially be developed clinically to target human malignancies. PMID:22130369

  1. Inhibition of REST Suppresses Proliferation and Migration in Glioblastoma Cells.

    PubMed

    Zhang, Dianbao; Li, Ying; Wang, Rui; Li, Yunna; Shi, Ping; Kan, Zhoumi; Pang, Xining

    2016-01-01

    Glioblastoma (GBM) is the most common primary brain tumor, with poor prognosis and a lack of effective therapeutic options. The aberrant expression of transcription factor REST (repressor element 1-silencing transcription factor) had been reported in different kinds of tumors. However, the function of REST and its mechanisms in GBM remain elusive. Here, REST expression was inhibited by siRNA silencing in U-87 and U-251 GBM cells. Then CCK-8 assay showed significantly decreased cell proliferation, and the inhibition of migration was verified by scratch wound healing assay and transwell assay. Using cell cycle analysis and Annexin V/PI straining assay, G1 phase cell cycle arrest was found to be a reason for the suppression of cell proliferation and migration upon REST silencing, while apoptosis was not affected by REST silencing. Further, the detection of REST-downstream genes involved in cytostasis and migration inhibition demonstrated that CCND1 and CCNE1 were reduced; CDK5R1, BBC3, EGR1, SLC25A4, PDCD7, MAPK11, MAPK12, FADD and DAXX were enhanced, among which BBC3 and DAXX were direct targets of REST, as verified by ChIP (chromatin immunoprecipitation) and Western blotting. These data suggested that REST is a master regulator that maintains GBM cells proliferation and migration, partly through regulating cell cycle by repressing downstream genes, which might represent a potential target for GBM therapy. PMID:27153061

  2. Inhibition of REST Suppresses Proliferation and Migration in Glioblastoma Cells

    PubMed Central

    Zhang, Dianbao; Li, Ying; Wang, Rui; Li, Yunna; Shi, Ping; Kan, Zhoumi; Pang, Xining

    2016-01-01

    Glioblastoma (GBM) is the most common primary brain tumor, with poor prognosis and a lack of effective therapeutic options. The aberrant expression of transcription factor REST (repressor element 1-silencing transcription factor) had been reported in different kinds of tumors. However, the function of REST and its mechanisms in GBM remain elusive. Here, REST expression was inhibited by siRNA silencing in U-87 and U-251 GBM cells. Then CCK-8 assay showed significantly decreased cell proliferation, and the inhibition of migration was verified by scratch wound healing assay and transwell assay. Using cell cycle analysis and Annexin V/PI straining assay, G1 phase cell cycle arrest was found to be a reason for the suppression of cell proliferation and migration upon REST silencing, while apoptosis was not affected by REST silencing. Further, the detection of REST-downstream genes involved in cytostasis and migration inhibition demonstrated that CCND1 and CCNE1 were reduced; CDK5R1, BBC3, EGR1, SLC25A4, PDCD7, MAPK11, MAPK12, FADD and DAXX were enhanced, among which BBC3 and DAXX were direct targets of REST, as verified by ChIP (chromatin immunoprecipitation) and Western blotting. These data suggested that REST is a master regulator that maintains GBM cells proliferation and migration, partly through regulating cell cycle by repressing downstream genes, which might represent a potential target for GBM therapy. PMID:27153061

  3. Lysyl oxidase propeptide inhibits smooth muscle cell signaling and proliferation

    SciTech Connect

    Hurtado, Paola A.; Vora, Siddharth; Sume, Siddika Selva; Yang, Dan; Hilaire, Cynthia St.; Guo Ying; Palamakumbura, Amitha H.; Schreiber, Barbara M.; Ravid, Katya; Trackman, Philip C.

    2008-02-01

    Lysyl oxidase is required for the normal biosynthesis and maturation of collagen and elastin. It is expressed by vascular smooth muscle cells, and its increased expression has been previously found in atherosclerosis and in models of balloon angioplasty. The lysyl oxidase propeptide (LOX-PP) has more recently been found to have biological activity as a tumor suppressor, and it inhibits Erk1/2 Map kinase activation. We reasoned that LOX-PP may have functions in normal non-transformed cells. We, therefore, investigated its effects on smooth muscle cells, focusing on important biological processes mediated by Erk1/2-dependent signaling pathways including proliferation and matrix metalloproteinase-9 (MMP-9) expression. In addition, we investigated whether evidence for accumulation of LOX-PP could be found in vivo in a femoral artery injury model. Recombinant LOX-PP was expressed and purified, and was found to inhibit primary rat aorta smooth muscle cell proliferation and DNA synthesis by more than 50%. TNF-{alpha}-stimulated MMP-9 expression and Erk1/2 activation were both significantly inhibited by LOX-PP. Immunohistochemistry studies carried out with affinity purified anti-LOX-PP antibody showed that LOX-PP epitopes were expressed at elevated levels in vascular lesions of injured arteries. These novel data suggest that LOX-PP may provide a feedback control mechanism that serves to inhibit properties associated with the development of vascular pathology.

  4. Miconia sp. Increases mRNA Levels of PPAR Gamma and Inhibits Alpha Amylase and Alpha Glucosidase

    PubMed Central

    Ortíz-Martinez, David Mizael; Rivas-Morales, Catalina; de la Garza-Ramos, Myriam Angelica; Verde-Star, Maria Julia; Nuñez-Gonzalez, Maria Adriana

    2016-01-01

    Diabetes mellitus is a public health problem worldwide. For this reason, ethanolic extract of Miconia sp. from Oaxaca, Mexico, was selected in search of an alternative against this disease. The effect of Miconia sp. on mRNA expression of PPARγ on cell line 3T3-L1, its effect on alpha amylase and alpha glucosidase, lipid accumulation during adipogenesis, and cell viability on VERO cells were evaluated. The mRNA levels of PPARγ increased on 1.393 ± 0.008 folds, lipid accumulation was increased by 29.55% with Miconia sp. extract and 34.57% with rosiglitazone, and α-amylase and α-glycosidase were inhibited with IC50 values from 28.23 ± 2.15 μg/mL and 1.95 ± 0.15 μg/mL, respectively; the IC50 on antiproliferative activity on VERO cells was 314.54 ± 45.40 μg/mL. In case of α-amylase and α-glycosidase assays, IC50 (inhibitory concentration 50) refers to necessary extract amounts to inhibit 50% of enzymatic activity. On the other hand, on antiproliferative activity, IC50 (inhibitory concentration 50) refers to necessary extract amounts to inhibit 50% of cell proliferation. It was concluded that the compounds present in Miconia sp. ethanolic extract increase mRNA expression of PPARγ, inhibit α-amylase and α-glucosidase, and increase lipid accumulation. It constitutes an alternative as adjuvant in diabetes mellitus treatment; therefore, we recommend continuing identifying the compounds responsible for its promising in vivo antidiabetic activity. PMID:27478477

  5. Miconia sp. Increases mRNA Levels of PPAR Gamma and Inhibits Alpha Amylase and Alpha Glucosidase.

    PubMed

    Ortíz-Martinez, David Mizael; Rivas-Morales, Catalina; de la Garza-Ramos, Myriam Angelica; Verde-Star, Maria Julia; Nuñez-Gonzalez, Maria Adriana; Leos-Rivas, Catalina

    2016-01-01

    Diabetes mellitus is a public health problem worldwide. For this reason, ethanolic extract of Miconia sp. from Oaxaca, Mexico, was selected in search of an alternative against this disease. The effect of Miconia sp. on mRNA expression of PPARγ on cell line 3T3-L1, its effect on alpha amylase and alpha glucosidase, lipid accumulation during adipogenesis, and cell viability on VERO cells were evaluated. The mRNA levels of PPARγ increased on 1.393 ± 0.008 folds, lipid accumulation was increased by 29.55% with Miconia sp. extract and 34.57% with rosiglitazone, and α-amylase and α-glycosidase were inhibited with IC50 values from 28.23 ± 2.15 μg/mL and 1.95 ± 0.15 μg/mL, respectively; the IC50 on antiproliferative activity on VERO cells was 314.54 ± 45.40 μg/mL. In case of α-amylase and α-glycosidase assays, IC50 (inhibitory concentration 50) refers to necessary extract amounts to inhibit 50% of enzymatic activity. On the other hand, on antiproliferative activity, IC50 (inhibitory concentration 50) refers to necessary extract amounts to inhibit 50% of cell proliferation. It was concluded that the compounds present in Miconia sp. ethanolic extract increase mRNA expression of PPARγ, inhibit α-amylase and α-glucosidase, and increase lipid accumulation. It constitutes an alternative as adjuvant in diabetes mellitus treatment; therefore, we recommend continuing identifying the compounds responsible for its promising in vivo antidiabetic activity. PMID:27478477

  6. Carbendazim Inhibits Cancer Cell Proliferation by Suppressing Microtubule Dynamics

    PubMed Central

    Yenjerla, Mythili; Cox, Corey; Wilson, Leslie; Jordan, Mary Ann

    2009-01-01

    Carbendazim (methyl 2-benzimidazolecarbamate) is widely used as a systemic fungicide in human food production and appears to act on fungal tubulin. However, it also inhibits proliferation of human cancer cells, including drug- and multidrug-resistant and p53-deficient cell lines. Because of its promising preclinical anti-tumor activity, it has undergone phase I clinical trials and is under further clinical development. Although it weakly inhibits polymerization of brain microtubules and induces G2/M arrest in tumor cells, its mechanism of action in human cells has not been fully elucidated. We examined its mechanism of action in MCF7 human breast cancer cells and found that it inhibits proliferation (IC50, 10 μM) and half-maximally arrests mitosis at a similar concentration (8 μM), in concert with suppression of microtubule dynamic instability without appreciable microtubule depolymerization. It induces mitotic spindle abnormalities and reduces the metaphase intercentromere distance of sister chromatids, indicating reduction of tension on kinetochores, thus leading to metaphase arrest. With microtubules assembled in vitro from pure tubulin, carbendazim also suppresses dynamic instability, reducing the dynamicity by 50% at 10 μM, with only minimal (21%) reduction of polymer mass. Carbendazim binds to mammalian tubulin (Kd, 42.8 ± 4.0 μM). Unlike some benzimidazoles that bind to the colchicine site in tubulin, carbendazim neither competes with colchicine nor competes with vinblastine for binding to brain tubulin. Thus, carbendazim binds to an as yet unidentified site in tubulin and inhibits tumor cell proliferation by suppressing the growing and shortening phases of microtubule dynamic instability, thus inducing mitotic arrest. PMID:19001156

  7. Blocking p55PIK signaling inhibits proliferation and induces differentiation of leukemia cells.

    PubMed

    Wang, G; Deng, Y; Cao, X; Lai, S; Tong, Y; Luo, X; Feng, Y; Xia, X; Gong, J; Hu, J

    2012-11-01

    p55PIK, a regulatory subunit of phosphatidylinositol 3-kinases, promotes cell cycle progression by interacting with cell cycle modulators such as retinoblastoma protein (Rb) via its unique amino-terminal 24 amino-acid residue (N24). Overexpression of N24 specifically inhibits these interactions and leads to cell cycle arrest. Herein, we describe the generation of a fusion protein (Tat transactivator protein (TAT)-N24) that contains the protein transduction domain and N24, and examined its effects on the proliferation and differentiation of leukemia cells. TAT-N24 not only blocks cell proliferation but remarkably induces differentiation of leukemia cells in vitro and in vivo. Systemically administered TAT-N24 also significantly decreases growth of leukemia cell tumors in animal models. Furthermore, overexpression of p55PIK in leukemia cells leads to increased proliferation; however, TAT-N24 blocks this effect and concomitantly induces differentiation. There is significant upregulation of p55PIK mRNA and protein expression in leukemia cells from patients. TAT-N24 inhibits cell cycle progression and induces differentiation of bone marrow cells derived from patients with several different types of leukemia. These results show that cell-permeable N24 peptide induces leukemia cell differentiation and suggest that p55PIK may be a novel drug target for the treatment of hematopoetic malignancies. PMID:22722333

  8. Skeletal unloading inhibits the in vitro proliferation and differentiation of rat osteoprogenitor cells

    NASA Technical Reports Server (NTRS)

    Kostenuik, P. J.; Halloran, B. P.; Morey-Holton, E. R.; Bikle, D. D.

    1997-01-01

    Loss of weight bearing in the growing rat decreases bone formation, osteoblast numbers, and bone maturation in unloaded bones. These responses suggest an impairment of osteoblast proliferation and differentiation. To test this assumption, we assessed the effects of skeletal unloading using an in vitro model of osteoprogenitor cell differentiation. Rats were hindlimb elevated for 0 (control), 2, or 5 days, after which their tibial bone marrow stromal cells (BMSCs) were harvested and cultured. Five days of hindlimb elevation led to significant decreases in proliferation, alkaline phosphatase (AP) enzyme activity, and mineralization of BMSC cultures. Differentiation of BMSCs was analyzed by quantitative competitive polymerase chain reaction of cDNA after 10, 15, 20, and 28 days of culture. cDNA pools were analyzed for the expression of c-fos (an index of proliferation), AP (an index of early osteoblast differentiation), and osteocalcin (a marker of late differentiation). BMSCs from 5-day unloaded rats expressed 50% less c-fos, 61% more AP, and 35% less osteocalcin mRNA compared with controls. These data demonstrate that cultured osteoprogenitor cells retain a memory of their in vivo loading history and indicate that skeletal unloading inhibits proliferation and differentiation of osteoprogenitor cells in vitro.

  9. Atypical role of sprouty in p21 dependent inhibition of cell proliferation in colorectal cancer.

    PubMed

    Zhang, Qiong; Shim, Katherine; Wright, Kevin; Jurkevich, Alexander; Khare, Sharad

    2016-09-01

    Sprouty (SPRY) appears to act as a tumor suppressor in cancer, whereas we reported that SPRY2 functions as a putative oncogene in colorectal cancer (CRC) [Oncogene, 2010, 29: 5241-5253]. In general, various studies established inhibition of cell proliferation by SPRY in cancer. The mechanisms by which SPRY regulates cell proliferation in CRC are investigated. We demonstrate, for the first time, suppression of SPRY2 augmented EGF-dependent oncogenic signaling, however, surprisingly decreased cell proliferation in colon cancer cells. Our data suggest that cell cycle inhibitor p21(WAF1/CIP1) transcriptional activity being regulated by SPRY2. Indeed, suppression of SPRY2 significantly increased p21(WAF1/CIP1) mRNA and protein expression as well as p21(WAF1/CIP1) promoter activity. Conversely, overexpressing SPRY2 triggered a decrease in p21(WAF1/CIP1) promoter activity. Concurrent down-regulation of both SPRY1 and SPRY2 also increased p21(WAF1/CIP1) expression in colon cancer cells. Increased nuclear localization of p21(WAF1/CIP1) in SPRY2 downregulated colon cancer cells may explain the inhibition of cell proliferation in colon cancer cells. Underscoring the biological relevance of these findings in SPRY1 and SPRY2 mutant mouse, recombination of floxed SPRY1 and SPRY2 alleles in mouse embryonic fibroblasts (MEFs) resulted in increased expression and nuclear localization of p21(WAF1/CIP1) and decreased cell proliferation. In CRC, the relationship of SPRY with p21 may provide unique strategies for cancer prevention and treatment. © 2015 The Authors. Molecular Carcinogenesis published by Wiley Periodicals, Inc. PMID:26293890

  10. In vivo inhibition of nitric oxide synthase impairs upregulation of contractile protein mRNA in overloaded plantaris muscle.

    PubMed

    Sellman, Jeff E; DeRuisseau, Keith C; Betters, Jenna L; Lira, Vitor A; Soltow, Quinlyn A; Selsby, Joshua T; Criswell, David S

    2006-01-01

    Inhibition of nitric oxide synthase (NOS) activity in vivo impedes hypertrophy in the overloaded rat plantaris. We investigated the mechanism for this effect by examining early events leading to muscle growth following 5 or 12 days of functional overload. Male Sprague-Dawley rats (approximately 350 g) were randomly divided into three treatment groups: control, N(G)-nitro-L-arginine methyl ester (L-NAME; 90 mg.kg(-1).day(-1)), and 1-(2-trifluoromethyl-phenyl)-imidazole (TRIM; 10 mg.kg(-1).day(-1)). Unilateral removal of synergists induced chronic overload (OL) of the right plantaris. Sham surgery performed on the left hindlimb served as a normally loaded control. L-NAME and TRIM treatments prevented OL-induced skeletal alpha-actin and type I (slow) myosin heavy chain mRNA expression at 5 days. Conversely, neither L-NAME nor TRIM affected hepatocyte growth factor or VEGF mRNA responses to OL at 5 days. However, OL induction of IGF-I and mechanogrowth factor mRNA was greater (P < 0.05) in the TRIM group compared with the controls. Furthermore, the phosphorylated-to-total p70 S6 kinase ratio was higher in OL muscle from NOS-inhibited groups, compared with control OL. At 12 days of OL, the cumulative proliferation of plantaris satellite cells was assessed by subcutaneous implantation of time release 5'-bromo-2'-deoxyuridine pellets during the OL-inducing surgeries. Although OL caused a fivefold increase in the number of mitotically active (5'-bromo-2'-deoxyuridine positive) sublaminar nuclei, this was unaffected by concurrent NOS inhibition. Therefore, NOS activity may provide negative feedback control of IGF-I/p70 S6 kinase signaling during muscle growth. Moreover, NOS activity may be involved in transcriptional regulation of skeletal alpha-actin and type I (slow) myosin heavy chain during functional overload. PMID:16166235

  11. Ribozyme cleaves rex/tax mRNA and inhibits bovine leukemia virus expression.

    PubMed Central

    Cantor, G H; McElwain, T F; Birkebak, T A; Palmer, G H

    1993-01-01

    Bovine leukemia virus (BLV) encodes at least two regulatory proteins, Rex and Tax. Tax, the transactivating protein, stimulates the long terminal repeat to promote viral transcription and may be involved in tumorigenesis. Rex is involved in the transition from early expression of regulatory proteins to later expression of viral structural proteins. We have targeted ribozymes against the mRNA encoding Rex and Tax. The ribozymes consist of the hammer-head catalytic motif flanked by antisense sequences that hybridize with the complementary rex/tax mRNA. To evaluate cleavage in a cell-free system, we transcribed portions of rex/tax mRNA and incubated them with synthetic RNA ribozymes. A ribozyme was identified that cleaves > 80% of the target RNA. Synthetic DNA encoding this ribozyme was cloned into the expression vector pRc/RSV and transfected into BLV-infected bat lung cells. Intracellular cleavage of rex/tax mRNA was confirmed by reverse transcriptase PCR. In cells expressing the ribozyme, viral expression was markedly inhibited. Expression of the BLV core protein p24 was inhibited by 61%, and reverse transcriptase activity in supernatant was inhibited by 92%. Ribozyme inhibition of BLV expression suggests that cattle expressing these sequences may be able to control BLV replication. Images Fig. 2 Fig. 4 Fig. 5 Fig. 6 PMID:7504287

  12. The Hippo pathway mediates inhibition of vascular smooth muscle cell proliferation by cAMP

    PubMed Central

    Kimura, Tomomi E.; Duggirala, Aparna; Smith, Madeleine C.; White, Stephen; Sala-Newby, Graciela B.; Newby, Andrew C.; Bond, Mark

    2016-01-01

    Aims Inhibition of vascular smooth muscle cell (VSMC) proliferation by intracellular cAMP prevents excessive neointima formation and hence angioplasty restenosis and vein-graft failure. These protective effects are mediated via actin-cytoskeleton remodelling and subsequent regulation of gene expression by mechanisms that are incompletely understood. Here we investigated the role of components of the growth-regulatory Hippo pathway, specifically the transcription factor TEAD and its co-factors YAP and TAZ in VSMC. Methods and results Elevation of cAMP using forskolin, dibutyryl-cAMP or the physiological agonists, Cicaprost or adenosine, significantly increased phosphorylation and nuclear export YAP and TAZ and inhibited TEAD-luciferase report gene activity. Similar effects were obtained by inhibiting RhoA activity with C3-transferase, its downstream kinase, ROCK, with Y27632, or actin-polymerisation with Latrunculin-B. Conversely, expression of constitutively-active RhoA reversed the inhibitory effects of forskolin on TEAD-luciferase. Forskolin significantly inhibited the mRNA expression of the pro-mitogenic genes, CCN1, CTGF, c-MYC and TGFB2 and this was reversed by expression of constitutively-active YAP or TAZ phospho-mutants. Inhibition of YAP and TAZ function with RNAi or Verteporfin significantly reduced VSMC proliferation. Furthermore, the anti-mitogenic effects of forskolin were reversed by overexpression of constitutively-active YAP or TAZ. Conclusion Taken together, these data demonstrate that cAMP-induced actin-cytoskeleton remodelling inhibits YAP/TAZ–TEAD dependent expression of pro-mitogenic genes in VSMC. This mechanism contributes novel insight into the anti-mitogenic effects of cAMP in VSMC and suggests a new target for intervention. PMID:26625714

  13. Maduramicin Inhibits Proliferation and Induces Apoptosis in Myoblast Cells

    PubMed Central

    Chen, Xin; Gu, Ying; Singh, Karnika; Shang, Chaowei; Barzegar, Mansoureh; Jiang, Shanxiang; Huang, Shile

    2014-01-01

    Maduramicin, a polyether ionophore antibiotic derived from the bacterium Actinomadura yumaensis, is currently used as a feed additive against coccidiosis in poultry worldwide. It has been clinically observed that maduramicin can cause skeletal muscle and heart cell damage, resulting in skeletal muscle degeneration, heart failure, and even death in animals and humans, if improperly used. However, the mechanism of its toxic action in myoblasts is not well understood. Using mouse myoblasts (C2C12) and human rhabdomyosarcoma (RD and Rh30) cells as an experimental model for myoblasts, here we found that maduramicin inhibited cell proliferation and induced cell death in a concentration-dependent manner. Further studies revealed that maduramicin induced accumulation of the cells at G0/G1 phase of the cell cycle, and induced apoptosis in the cells. Concurrently, maduramicin downregulated protein expression of cyclin D1, cyclin-dependent kinases (CDK4 and CDK6), and CDC25A, and upregulated expression of the CDK inhibitors (p21Cip1 and p27Kip1), resulting in decreased phosphorylation of Rb. Maduramicin also induced expression of BAK, BAD, DR4, TRADD and TRAIL, leading to activation of caspases 8, 9 and 3 as well as cleavage of poly ADP ribose polymerase (PARP). Taken together, our results suggest that maduramicin executes its toxicity in myoblasts at least by inhibiting cell proliferation and inducing apoptotic cell death. PMID:25531367

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

    SciTech Connect

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

    2011-06-10

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

  15. Maduramicin inhibits proliferation and induces apoptosis in myoblast cells.

    PubMed

    Chen, Xin; Gu, Ying; Singh, Karnika; Shang, Chaowei; Barzegar, Mansoureh; Jiang, Shanxiang; Huang, Shile

    2014-01-01

    Maduramicin, a polyether ionophore antibiotic derived from the bacterium Actinomadura yumaensis, is currently used as a feed additive against coccidiosis in poultry worldwide. It has been clinically observed that maduramicin can cause skeletal muscle and heart cell damage, resulting in skeletal muscle degeneration, heart failure, and even death in animals and humans, if improperly used. However, the mechanism of its toxic action in myoblasts is not well understood. Using mouse myoblasts (C2C12) and human rhabdomyosarcoma (RD and Rh30) cells as an experimental model for myoblasts, here we found that maduramicin inhibited cell proliferation and induced cell death in a concentration-dependent manner. Further studies revealed that maduramicin induced accumulation of the cells at G0/G1 phase of the cell cycle, and induced apoptosis in the cells. Concurrently, maduramicin downregulated protein expression of cyclin D1, cyclin-dependent kinases (CDK4 and CDK6), and CDC25A, and upregulated expression of the CDK inhibitors (p21Cip1 and p27Kip1), resulting in decreased phosphorylation of Rb. Maduramicin also induced expression of BAK, BAD, DR4, TRADD and TRAIL, leading to activation of caspases 8, 9 and 3 as well as cleavage of poly ADP ribose polymerase (PARP). Taken together, our results suggest that maduramicin executes its toxicity in myoblasts at least by inhibiting cell proliferation and inducing apoptotic cell death. PMID:25531367

  16. Downregulation of VEGFA inhibits proliferation, promotes apoptosis, and suppresses migration and invasion of renal clear cell carcinoma

    PubMed Central

    Zeng, Fan-Chang; Zeng, Ming-Qiang; Huang, Liang; Li, Yong-Lin; Gao, Ben-Min; Chen, Jun-Jie; Xue, Rui-Zhi; Tang, Zheng-Yan

    2016-01-01

    Objective The aim of this study was to investigate the effects of vascular endothelial growth factor A (VEGFA) on cell proliferation, apoptosis, migration, and invasion in renal clear cell carcinoma (RCCC). Methods Between June 2012 and June 2015, RCCC tissues were obtained for the experimental group, and RCCC adjacent tumor-free kidney parenchyma tissues were obtained for the control group. VEGFA mRNA and protein expressions and phosphoinositide 3-kinase, serine/threonine-specific protein kinase (AKT), and phosphorylated-AKT protein expressions were detected. The chemically synthesized specific siRNA using RNA interference technology was used to inhibit VEGFA gene expression in human RCCC 786-O cells. The negative control (NC) group was transfected with NC sequence, and the blank group was transfected with no sequence. Flow cytometry, scratch test, and cell-penetrating experiment were used to detect cell proliferation, apoptosis, migration, and invasion of 786-O cells. Results Positive expression of VEGFA protein was 60.62% in RCCC tissue and 18.34% in adjacent tissue with statistically significant difference (P<0.001). VEGFA protein and mRNA expressions were higher in RCCC tissue than those in adjacent tissue (both P<0.01). VEGF expression in RCCC tissue was associated with Fuhrman grading and American Joint Committee on Cancer staging (both P<0.05). After RCCC 786-O cells transfecting the VEGFA siRNA, the VEGFA mRNA and protein expressions and phosphoinositide 3-kinase and phosphorylated-AKT protein expressions were significantly decreased, cell proliferation was remarkably inhibited, cell apoptotic ratio was obviously increased, and migration distance and invasive cell number were markedly decreased compared to those in the NC group and the blank group (all P<0.05). Conclusion Inhibition of VEGFA inhibited proliferation, promoted apoptosis, and suppressed migration and invasion of RCCC 786-O cells. VEGF has a potential role in diagnosis and therapy of RCCC

  17. Thrombospondin 2 Inhibits Microvascular Endothelial Cell Proliferation by a Caspase-independent Mechanism

    PubMed Central

    Armstrong, Lucas C.; Björkblom, Benny; Hankenson, Kurt D.; Siadak, Anthony W.; Stiles, Charlotte E.; Bornstein, Paul

    2002-01-01

    The matricellular protein thrombospondin 2 (TSP2) regulates a variety of cell–matrix interactions. A prominent feature of TSP2-null mice is increased microvascular density, particularly in connective tissues synthesized after injury. We investigated the cellular basis for the regulation of angiogenesis by TSP2 in cultures of murine and human fibroblasts and endothelial cells. Fibroblasts isolated from murine and human dermis synthesize TSP2 mRNA and secrete significant amounts of immunoreactive TSP2, whereas endothelial cells from mouse lung and human dermis did not synthesize TSP2 mRNA or protein. Recombinant mouse TSP2 inhibited growth of human microvascular endothelial cells (HMVECs) mediated by basic fibroblast growth factor, insulin-like growth factor-1, epidermal growth factor, and vascular endothelial growth factor (VEGF). HMVECs exposed to TSP2 in the presence of these growth factors had a decreased proportion of cells in S and G2/M phases. HMVECs cultured with a combination of basic fibroblast growth factor, insulin-like growth factor-1, and epidermal growth factor displayed an increased proportion of nonviable cells in the presence of TSP2, but the addition of VEGF blocked this TSP2-mediated impairment of cell viability. TSP2-mediated inhibition of DNA synthesis by HMVECs in the presence of VEGF was not affected by the broad-spectrum caspase inhibitor zVAD-fmk. Similar findings were obtained with TSP1. Taken together, these observations indicate that either TSP2 or TSP1 can inhibit HMVEC proliferation by inhibition of cell cycle progression and induction of cell death, but the mechanisms responsible for TSP2-mediated inhibition of cell cycle progression are independent from those leading to cell death. PMID:12058057

  18. Neutrophil-derived alpha defensins control inflammation by inhibiting macrophage mRNA translation.

    PubMed

    Brook, Matthew; Tomlinson, Gareth H; Miles, Katherine; Smith, Richard W P; Rossi, Adriano G; Hiemstra, Pieter S; van 't Wout, Emily F A; Dean, Jonathan L E; Gray, Nicola K; Lu, Wuyuan; Gray, Mohini

    2016-04-19

    Neutrophils are the first and most numerous cells to arrive at the site of an inflammatory insult and are among the first to die. We previously reported that alpha defensins, released from apoptotic human neutrophils, augmented the antimicrobial capacity of macrophages while also inhibiting the biosynthesis of proinflammatory cytokines. In vivo, alpha defensin administration protected mice from inflammation, induced by thioglychollate-induced peritonitis or following infection withSalmonella entericaserovar Typhimurium. We have now dissected the antiinflammatory mechanism of action of the most abundant neutrophil alpha defensin, Human Neutrophil Peptide 1 (HNP1). Herein we show that HNP1 enters macrophages and inhibits protein translation without inducing the unfolded-protein response or affecting mRNA stability. In a cell-free in vitro translation system, HNP1 powerfully inhibited both cap-dependent and cap-independent mRNA translation while maintaining mRNA polysomal association. This is, to our knowledge, the first demonstration of a peptide released from one cell type (neutrophils) directly regulating mRNA translation in another (macrophages). By preventing protein translation, HNP1 functions as a "molecular brake" on macrophage-driven inflammation, ensuring both pathogen clearance and the resolution of inflammation with minimal bystander tissue damage. PMID:27044108

  19. Viscum album-Mediated COX-2 Inhibition Implicates Destabilization of COX-2 mRNA

    PubMed Central

    Saha, Chaitrali; Hegde, Pushpa; Friboulet, Alain; Bayry, Jagadeesh; Kaveri, Srinivas V.

    2015-01-01

    Extensive use of Viscum album (VA) preparations in the complementary therapy of cancer and in several other human pathologies has led to an increasing number of cellular and molecular approaches to explore the mechanisms of action of VA. We have recently demonstrated that, VA preparations exert a potent anti-inflammatory effect by selectively down-regulating the COX-2-mediated cytokine-induced secretion of prostaglandin E2 (PGE2), one of the important molecular signatures of inflammatory reactions. In this study, we observed a significant down-regulation of COX-2 protein expression in VA-treated A549 cells however COX-2 mRNA levels were unaltered. Therefore, we hypothesized that VA induces destabilisation of COX-2 mRNA, thereby depleting the available functional COX-2 mRNA for the protein synthesis and for the subsequent secretion of PGE2. To address this question, we analyzed the molecular degradation of COX-2 protein and its corresponding mRNA in A549 cell line. Using cyclohexamide pulse chase experiment, we demonstrate that, COX-2 protein degradation is not affected by the treatment with VA whereas experiments on transcriptional blockade with actinomycin D, revealed a marked reduction in the half life of COX-2 mRNA due to its rapid degradation in the cells treated with VA compared to that in IL-1β-stimulated cells. These results thus demonstrate that VA-mediated inhibition of PGE2 implicates destabilization of COX-2 mRNA. PMID:25664986

  20. Inhibition of TRPM7 by carvacrol suppresses glioblastoma cell proliferation, migration and invasion

    PubMed Central

    Chen, Wen-Liang; Barszczyk, Andrew; Turlova, Ekaterina; Deurloo, Marielle; Liu, Baosong; Yang, Burton B.; Rutka, James T.; Feng, Zhong-Ping; Sun, Hong-Shuo

    2015-01-01

    Glioblastomas are progressive brain tumors with devastating proliferative and invasive characteristics. Ion channels are the second largest target class for drug development. In this study, we investigated the effects of the TRPM7 inhibitor carvacrol on the viability, resistance to apoptosis, migration, and invasiveness of the human U87 glioblastoma cell line. The expression levels of TRPM7 mRNA and protein in U87 cells were detected by RT-PCR, western blotting and immunofluorescence. TRPM7 currents were recorded using whole-cell patch-clamp techniques. An MTT assay was used to assess cell viability and proliferation. Wound healing and transwell experiments were used to evaluate cell migration and invasion. Protein levels of p-Akt/t-Akt, p-ERK1/2/t-ERK1/2, cleaved caspase-3, MMP-2 and phosphorylated cofilin were also detected. TRPM7 mRNA and protein expression in U87 cells is higher than in normal human astrocytes. Whole-cell patch-clamp recording showed that carvacrol blocks recombinant TRPM7 current in HEK293 cells and endogenous TRPM7-like current in U87 cells. Carvacrol treatment reduced the viability, migration and invasion of U87 cells. Carvacrol also decreased MMP-2 protein expression and promoted the phosphorylation of cofilin. Furthermore, carvacrol inhibited the Ras/MEK/MAPK and PI3K/Akt signaling pathways. Therefore, carvacrol may have therapeutic potential for the treatment of glioblastomas through its inhibition of TRPM7 channels. PMID:25965832

  1. miR-138 suppresses cell proliferation and invasion by inhibiting SOX9 in hepatocellular carcinoma

    PubMed Central

    Liu, Yahui; Zhang, Wei; Liu, Kai; Liu, Songyang; Ji, Bai; Wang, Yingchao

    2016-01-01

    Accumulating evidence suggests that miR-138 expression was frequently downregulated in different cancer types and involves in the progression of tumorigenesis. However, the biological role and molecular mechanism of miR-138 involvement in hepatocellular carcinoma (HCC) still remains largely unknown. Therefore, in the present study, we investigated the role of miR-138 in the progression of HCC. We found that miR-138 expression levels were significantly downregulated in HCC tissues and cell lines compared with the corresponding noncancerous liver tissues and normal hepatic cell line. In addition, we also found that enforced expression of miR-138 inhibited proliferation, colony formation, migration and invasion in HCC cells. Using a luciferase reporter assay, SOX9 was confirmed as a direct target of miR-138. Quantitative real-time polymerase chain reaction (qRT-PCR) and western blot assay showed that overexpression of miR-138 in HCC cells significantly inhibited SOX9 expression on mRNA level and protein level. Furthermore, SOX9 expression was significantly upregulated in HCC tissues and cell lines, and its mRNA expression is negative correlated with miR-138 expression in clinical HCC tissues (r=-0.689, P<0.01). Of note, downregulation of SOX9 performed similar effects with overexpression of miR-138. These findings suggested that miR-138 functioned as a tumor suppressor in HCC partially via repressing SOX9 expression. PMID:27347323

  2. The combination of tetraiodothyroacetic acid and cetuximab inhibits cell proliferation in colorectal cancers with different K-ras status.

    PubMed

    Lee, Yee-Shin; Chin, Yu-Tang; Yang, Yu-Chen S H; Wei, Po-Li; Wu, Han-Chung; Shih, Ai; Lu, Yueh-Tong; Pedersen, Jens Z; Incerpi, Sandra; Liu, Leroy F; Lin, Hung-Yun; Davis, Paul J

    2016-07-01

    Thyroid hormone induces cancer cell proliferation through its cell surface receptor integrin αvβ3. Acting via integrin αvβ3, the deaminated T4 analog tetraiodothyroacetic acid (tetrac), and its nanoparticle formulation nano-diamino-tetrac (NDAT) could inhibit cell proliferation and xenograft growth. In this study, we investigated the T4 effects on proliferation in colorectal cancer cell lines based on the proliferation marker expressions at both mRNA and protein levels. The effects of tetrac/NDAT, the monoclonal anti-EGFR antibody cetuximab, and their combinations on colorectal cancer cell proliferation were examined according to the relevant gene expression profiles and cell count analysis. The results showed that T4 significantly enhanced PCNA, Cyclin D1 and c-Myc levels in both K-ras wild type HT-29 and mutant HCT 116 cells. In HCT 116 cells, the combination of NDAT and cetuximab significantly suppressed the mRNA expressions of proliferative genes PCNA, Cyclin D1, c-Myc and RRM2 raised by T4 compared to cetuximab alone. In addition, T4-suppressed mRNA expressions of pro-apoptotic genes p53 and RRM2B could be significantly elevated by the combination of NDAT and cetuximab compared to cetuximab alone. In the K-ras mutant HCT 116 cells, but not in the K-ras wild type COLO 205 cells, the combinations of tetrac/NDAT and cetuximab significantly reduced cell proliferation compared to cetuximab alone. In conclusion, T4 promoted colorectal cancer cell proliferation which could be repressed by tetrac and NDAT. The combinations of tetrac/NDAT and cetuximab potentiated cetuximab actions in K-ras mutant colorectal cancer cells. PMID:26980146

  3. miR-143 suppresses the proliferation of NSCLC cells by inhibiting the epidermal growth factor receptor

    PubMed Central

    Zhang, Hong-Bo; Sun, Li-Chao; Ling, Lan; Cong, Lu-Hong; Lian, Rui

    2016-01-01

    MicroRNAs (miRs) regulate the proliferation and metastasis of numerous cancer cell types. It was previously reported that miR-143 levels were downregulated in non-small cell lung cancer (NSCLC) tissues and cell lines, and that the migration and invasion of NSCLC cells was inhibited upon suppression of cell proliferation and colony formation by the upregulation of miR-143. Epidermal growth factor receptor (EGFR), which is a vital factor in the promotion of cancer cell proliferation and has been investigated as a potential focus in cancer therapy, has been reported to be a possible target of miR-143. The present study aimed to investigate the role of miR-143 in NSCLC using NSCLC cell lines and primary cells from NSCLC patients. NSCLC cells were co-transfected with EGFR and miR-143, and the mRNA and protein expression of EGFR were analyzed. Furthermore, the activity of the transfected cancer cells with regard to colony formation, migration, invasion and apoptosis were evaluated. The levels of miR-143 were decreased in the NSCLC cell lines and primary cells from patients with NSCLC compared with the controls. Following transfection with miR-143, the ability of NSCLC cells to proliferate, form colonies, migrate and invade was inhibited. Similarly, knockdown of EGFR led to the suppression of NSCLC cell proliferation. The mRNA and protein expression levels of EGFR were significantly reduced following miR-143 overexpression, and the level of miR-143 was inversely correlated with that of EGFR in NSCLC cells. The results of the present study demonstrated that miR-143 was able to suppress NSCLC cell proliferation and invasion by inhibiting the effects of EGFR, suggesting that EGFR may be considered a potential target for NSCLC therapy. PMID:27602093

  4. Kuwanon V Inhibits Proliferation, Promotes Cell Survival and Increases Neurogenesis of Neural Stem Cells

    PubMed Central

    Kong, Sun-Young; Park, Min-Hye; Lee, Mina; Kim, Jae-Ouk; Lee, Ha-Rim; Han, Byung Woo; Svendsen, Clive N.; Sung, Sang Hyun; Kim, Hyun-Jung

    2015-01-01

    Neural stem cells (NSCs) have the ability to proliferate and differentiate into neurons and glia. Regulation of NSC fate by small molecules is important for the generation of a certain type of cell. The identification of small molecules that can induce new neurons from NSCs could facilitate regenerative medicine and drug development for neurodegenerative diseases. In this study, we screened natural compounds to identify molecules that are effective on NSC cell fate determination. We found that Kuwanon V (KWV), which was isolated from the mulberry tree (Morus bombycis) root, increased neurogenesis in rat NSCs. In addition, during NSC differentiation, KWV increased cell survival and inhibited cell proliferation as shown by 5-bromo-2-deoxyuridine pulse experiments, Ki67 immunostaining and neurosphere forming assays. Interestingly, KWV enhanced neuronal differentiation and decreased NSC proliferation even in the presence of mitogens such as epidermal growth factor and fibroblast growth factor 2. KWV treatment of NSCs reduced the phosphorylation of extracellular signal-regulated kinase 1/2, increased mRNA expression levels of the cyclin-dependent kinase inhibitor p21, down-regulated Notch/Hairy expression levels and up-regulated microRNA miR-9, miR-29a and miR-181a. Taken together, our data suggest that KWV modulates NSC fate to induce neurogenesis, and it may be considered as a new drug candidate that can regenerate or protect neurons in neurodegenerative diseases. PMID:25706719

  5. Intracellular autocrine VEGF signaling promotes EBDC cell proliferation, which can be inhibited by Apatinib.

    PubMed

    Peng, Sui; Zhang, Yanyan; Peng, Hong; Ke, Zunfu; Xu, Lixia; Su, Tianhong; Tsung, Allan; Tohme, Samer; Huang, Hai; Zhang, Qiuyang; Lencioni, Riccardo; Zeng, Zhirong; Peng, Baogang; Chen, Minhu; Kuang, Ming

    2016-04-10

    Tumor cells produce vascular endothelial growth factor (VEGF) which can interact with membrane or cytoplasmic VEGF receptors (VEGFRs) to promote cell growth. We aimed to investigate the role of extracellular/intracellular autocrine VEGF signaling and Apatinib, a highly selective VEGFR2 inhibitor, in extrahepatic bile duct cancer (EBDC). We found conditioned medium or recombinant human VEGF treatment promoted EBDC cell proliferation through a phospholipase C-γ1-dependent pathway. This pro-proliferative effect was diminished by VEGF, VEGFR1 or VEGFR2 neutralizing antibodies, but more significantly suppressed by intracellular VEGFR inhibitor. The rhVEGF induced intracellular VEGF signaling by promoting nuclear accumulation of pVEGFR1/2 and enhancing VEGF promoter activity, mRNA and protein expression. Internal VEGFR2 inhibitor Apatinib significantly inhibited intracellular VEGF signaling, suppressed cell proliferation in vitro and delayed xenograft tumor growth in vivo, while anti-VEGF antibody Bevacizumab showed no effect. Clinically, overexpression of pVEGFR1 and pVEGFR2 was significantly correlated with poorer overall survival (P = .007 and P = .020, respectively). In conclusion, the intracellular autocrine VEGF loop plays a predominant role in VEGF-induced cell proliferation. Apatinib is an effective intracellular VEGF pathway blocker that presents a great therapeutic potential in EBDC. PMID:26805764

  6. Shikonin Suppresses Skin Carcinogenesis via Inhibiting Cell Proliferation.

    PubMed

    Li, Wenjuan; Zhang, Chunjing; Ren, Amy; Li, Teena; Jin, Rong; Li, Guohong; Gu, Xin; Shi, Runhua; Zhao, Yunfeng

    2015-01-01

    The M2 isoform of pyruvate kinase M2 (PKM2) has been shown to be up-regulated in human skin cancers. To test whether PKM2 may be a target for chemoprevention, shikonin, a natural product from the root of Lithospermum erythrorhizon and a specific inhibitor of PKM2, was used in a chemically-induced mouse skin carcinogenesis study. The results revealed that shikonin treatment suppressed skin tumor formation. Morphological examinations and immunohistochemical staining of the skin epidermal tissues suggested that shikonin inhibited cell proliferation without inducing apoptosis. Although shikonin alone suppressed PKM2 activity, it did not suppress tumor promoter-induced PKM2 activation in the skin epidermal tissues at the end of the skin carcinogenesis study. To reveal the potential chemopreventive mechanism of shikonin, an antibody microarray analysis was performed, and the results showed that the transcription factor ATF2 and its downstream target Cdk4 were up-regulated by chemical carcinogen treatment; whereas these up-regulations were suppressed by shikonin. In a promotable skin cell model, the nuclear levels of ATF2 were increased during tumor promotion, whereas this increase was inhibited by shikonin. Furthermore, knockdown of ATF2 decreased the expression levels of Cdk4 and Fra-1 (a key subunit of the activator protein 1. In summary, these results suggest that shikonin, rather than inhibiting PKM2 in vivo, suppresses the ATF2 pathway in skin carcinogenesis. PMID:25961580

  7. Blockade of MUC1 expression by glycerol guaiacolate inhibits proliferation of human breast cancer cells.

    PubMed

    Smith, J S; Colon, J; Madero-Visbal, R; Isley, B; Konduri, S D; Baker, C H

    2010-10-01

    We sought to determine whether administration of glycerol guaiacolate at an optimal biological dose inhibits human breast cancer cell growth. Human breast cancer MCF-7 and ZR-75-1 cells were treated with glycerol guaiacolate and the therapeutic efficacy and biological activity of this drug was investigated on breast cancer cell growth. MCF-7 cells were injected into the mammary fat pad of overectamized female athymic nude mice. Ten days later, animals were treated with daily intraperitoneal injections of glycerol guaiacolate for six weeks. Tumor size and volume was monitored and immunohistochemistry analysis on MUC1, p21 and ki-67 was performed. Glycerol guaiacolate decreased breast cancer cell growth in a dose-dependent manner, decreased cell migration, and caused G1 cell cycle arrest. Our results demonstrate that glycerol guaiacolate inhibits MUC1 protein and mRNA expression levels and significantly increased p21 expression in human breast cancer cells as well as induced PARP cleavage. Similarly, glycerol guaiacolate inhibited breast tumor growth in vivo as well as enhanced p21 expression and decreased breast tumor cell proliferation (ki-67 expression). Collectively, our results demonstrate that glycerol guaiacolate decreased MUC1 expression and enhanced cell growth inhibition by inducing p21 expression in breast cancer cells. These findings suggest that glycerol guaiacolate may provide a novel and effective approach for the treatment of human breast cancer. PMID:21184665

  8. Hedyotis diffusa Willd extract inhibits HT-29 cell proliferation via cell cycle arrest.

    PubMed

    Lin, Minghe; Lin, Jiumao; Wei, Lihui; Xu, Wei; Hong, Zhenfeng; Cai, Qiaoyan; Peng, Jun; Zhu, Dezeng

    2012-08-01

    Hedyotis diffusa Willd (HDW) has long been used as an important component in several Chinese medicine formulae to clinically treat various types of cancer, including colorectal cancer (CRC). Previously, we reported that HDW inhibits CRC growth via the induction of cancer cell apoptosis and the inhibition of tumor angiogenesis. In the present study, to further elucidate the mechanism of HDW-mediated antitumor activity, we investigated the effect of HDW ethanol extract (EEHDW) on the proliferation of HT-29 human colon carcinoma cells. We found that EEHDW reduced HT-29 cell viability and survival in a dose- and time-dependent manner. We also observed that EEHDW treatment blocked the cell cycle, preventing G1 to S progression, and reduced mRNA expression of pro-proliferative PCNA, Cyclin D1 and CDK4, but increased that of anti-proliferative p21. Our findings suggest that Hedyotis diffusa Willd may be an effective treatment for CRC via the suppression of cancer cell proliferation. PMID:23139718

  9. CXCL5 knockdown expression inhibits human bladder cancer T24 cells proliferation and migration

    SciTech Connect

    Zheng, Jiajia; Zhu, Xi; Zhang, Jie

    2014-03-28

    Highlights: • We first demonstrated CXCL5 is highly expressed in human bladder tumor tissues and cells. • CXCL5 knockdown inhibits proliferation, migration and promotes apoptosis in T24 cells. • CXCL5 knockdown inhibits Snail, PI3K-AKT and ERK1/2 signaling pathways in T24 cells. • CXCL5 is critical for bladder tumor growth and progression. - Abstract: CXCL5 (epithelial neutrophil activating peptide-78) which acts as a potent chemoattractant and activator of neutrophil function was reported to play a multifaceted role in tumorigenesis. To investigate the role of CXCL5 in bladder cancer progression, we examined the CXCL5 expression in bladder cancer tissues by real-time PCR and Western blot, additionally, we used shRNA-mediated silencing to generate stable CXCL5 silenced bladder cancer T24 cells and defined its biological functions. Our results demonstrated that mRNA and protein of CXCL5 is increased in human bladder tumor tissues and cell lines, down-regulation of CXCL5 in T24 cells resulted in significantly decreased cell proliferation, migration and increased cell apoptosis in vitro through Snail, PI3K-AKT and ERK1/2 signaling pathways. These data suggest that CXCL5 is critical for bladder tumor growth and progression, it may represent a potential application in cancer diagnosis and therapy.

  10. IL-24 is Expressed During Wound Repair and Inhibits TGFα induced Migration and Proliferation of Keratinocytes

    PubMed Central

    Poindexter, Nancy J.; Williams, Ryan R.; Powis, Garth; Jen, Emily; Caudle, Abigail S.; Chada, Sunil; Grimm, Elizabeth A.

    2011-01-01

    Interleukin (IL)-24 is the protein product of melanoma differentiation-associated gene 7 (MDA-7). Originally identified as a tumor suppressor molecule, MDA-7 was renamed IL-24 and classified as a cytokine because of its chromosomal location in the IL-10 locus, its mRNA expression in leukocytes, and its secretory sequence elements. We previously reported that IL-24 is expressed by cytokine-activated monocytes and T lymphocytes. Here, we show that IL-24 is expressed in keratinocytes during wound repair. Paraffin-embedded tissues prepared from human skin sampled at days 2, 6, and 10 after wounding were examined by immunohistochemistry for expression of IL-24. Protein expression was detected in the keratinocyte population with maximum expression at days 2 and 6; and no expression by day 10 (4 of 4 subjects). In vitro studies showed that cytokines involved in wound repair, most notably TGFα, TGFβ, IFNγ and IFNβ, upregulated IL-24 protein expression in normal human epidermal keratinocytes (NHEK). Examination of the function of IL-24 in both in vitro wound repair and migration assays demonstrated that IL-24 inhibits TGFα induced proliferation and migration of NHEKs. These data support the hypothesis that IL-24 functions during an inflammatory response in the skin by inhibiting the proliferation and migration of keratinocytes. PMID:20545760

  11. Cisplatin Inhibits Hippocampal Cell Proliferation and Alters the Expression of Apoptotic Genes

    PubMed Central

    Manohar, Senthilvelan; Jamesdaniel, Samson; Salvi, Richard

    2014-01-01

    The hippocampus, which is critical for memory and spatial navigation, contains a proliferating stem cell niche that is especially vulnerable to anti-neoplastic drugs such as cisplatin. Although the damaging effects of cisplatin have recently been recognized, the molecular mechanisms underlying its toxic effects on this vital region are largely unknown. Using a focused apoptosis gene array, we analyzed the early cisplatin-induced changes in gene expression in the hippocampus of adult Sprague-Dawley rats and compared the results to those from the inferior colliculus, a non-mitotic auditory region resistant to cisplatin-induced cell death. Two days after a 12 mg/kg dose of cisplatin, significant increases were observed in five proapoptotic genes Bik, Bid, Bok, Trp53p2 and Card6 and a significant decrease in one antiapoptotic gene Bcl2a1. In contrast, Nol3, an antiapoptotic gene showed a significant increase in expression. The cisplatin-induced increase in Bid mRNA and decrease in Bcl2a1 mRNA was accompanied by a corresponding increase and decrease of their respective proteins in the hippocampus. In contrast, the cisplatin-induced changes in Bcl2a1, Bid, Bik and Bok gene expression in the inferior colliculus were strikingly different from those in the hippocampus consistent with the greater susceptibility of the hippocampus to cisplatin toxicity. Cisplatin also significantly reduced immunolabeling of the cell proliferation marker Ki67 in the subgranular zone (SGZ) of the hippocampus two days post treatment. These results indicate that cisplatin-induced hippocampal cell death is mediated by increased expression of proapoptotic and antiapoptotic genes and proteins that likely inhibit hippocampal cell proliferation. PMID:24277158

  12. Proliferation of macrophages due to the inhibition of inducible nitric oxide synthesis by oxidized low-density lipoproteins

    PubMed Central

    Brunner, Monika; Gruber, Miriam; Schmid, Diethart; Baran, Halina; Moeslinger, Thomas

    2015-01-01

    Oxidized low-density lipoprotein (ox-LDL) is assumed to be a major causal agent in hypercholesteraemia-induced atherosclerosis. Because the proliferation of lipid-loaden macrophages within atherosclerotic lesions has been described, we investigated the dependence of macrophage proliferation on the inhibition of inducible nitric oxide synthase (iNOS) by hypochlorite oxidized LDL. Ox-LDL induces a dose dependent inhibition of inducible nitric oxide synthesis in lipopolysaccharide-interferon stimulated mouse macrophages (J774.A1) with concomitant macrophage proliferation as assayed by cell counting, tritiated-thymidine incorporation and measurement of cell protein. Native LDL did not influence macrophage proliferation and inducible nitric oxide synthesis. iNOS protein and mRNA was reduced by HOCl-oxidized LDL (0-40 µg/ml) as revealed by immunoblotting and competitive semiquantitative PCR. Macrophage proliferation was increased by the addition of the iNOS inhibitor L-NAME. The addition of ox-LDL to L-NAME containing incubations induced no further statistically significant increase in cell number. Nitric oxide donors decreased ox-LDL induced macrophage proliferation and nitric oxide scavengers restored macrophage proliferation to the initial values achieved by ox-LDL. The decrease of cytosolic DNA fragments in stimulated macrophages incubated with ox-LDL demonstrates that the proliferative actions of ox-LDL are associated with a decrease of NO-induced apoptosis. Our data show that inhibition of iNOS dependent nitric oxide production caused by hypochlorite oxidized LDL enhances macrophage proliferation. This might be a key event in the pathogenesis of atherosclerotic lesions. PMID:26600745

  13. Silencing of CDC42 inhibits neuroblastoma cell proliferation and transformation

    PubMed Central

    Lee, Sora; Craig, Brian T.; Romain, Carmelle V.; Qiao, Jingbo; Chung, Dai H.

    2014-01-01

    Cell division cycle 42 (CDC42), a small GTPase of the Rho-subfamily, regulates diverse cellular functions including proliferation, cytoskeletal rearrangement and even promotes malignant transformation. Here, we found that increased expression of CDC42 correlated with undifferentiated neuroblastoma as compared to a more benign phenotype. CDC42 inhibition decreased cell growth and soft agar colony formation, and increased cell death in BE(2)-C and BE(2)-M17 cell lines, but not in SK-N-AS. In addition, silencing of CDC42 decreased expression of N-myc in BE(2)-C and BE(2)-M17 cells. Our findings suggest that CDC42 may play a role in the regulation of aggressive neuroblastoma behavior. PMID:25264923

  14. BmKCT toxin inhibits glioma proliferation and tumor metastasis.

    PubMed

    Fan, Shaozhong; Sun, Zhengbo; Jiang, Dahe; Dai, Chao; Ma, Yibao; Zhao, Zhenhuan; Liu, Hui; Wu, Yingliang; Cao, Zhijian; Li, Wenxin

    2010-05-28

    Malignant gliomas are the most common primary brain tumors associated with significant morbidity and mortality. How to target the tumor in situ, and inhibit tumor cell proliferation and invasion is the key for therapy. Gliomas express a glioma-specific chloride ion channel that is sensitive to toxins including BmKCT. In the current study, the inhibitory effect of BmKCT on glioma growth was observed in vivo using the glioma/SD rat model. Furthermore, BmKCT prevented the metastasis of glioma cells in vivo. Moreover, biodistribution experiments with (l3l)I-labeled or Cy5.5-conjugated BmKCT revealed that BmKCT selectively targeted the glioma in situ. Our data suggest that BmKCT could be exploited as a potential therapeutic for glioma diagnosis and therapy. PMID:19906483

  15. Amlodipine inhibits cell proliferation via PKD1-related pathway

    SciTech Connect

    Ohba, Takayoshi; Watanabe, Hiroyuki; Murakami, Manabu; Radovanovic, Milena; Iino, Kenji; Ishida, Masaru; Tosa, Shinya; Ono, Kyoichi; Ito, Hiroshi

    2008-05-02

    Human coronary artery smooth muscle cell (hCASMC) proliferation is involved in the progression of coronary artery disease. Amlodipine, a widely used antihypertensive drug, exerts antiproliferative effects by increasing the expression of p21{sup (Waf1/Cip1)}. Polycystic kidney disease 1 (PKD1) is also involved in cell cycle inhibition via p21{sup (Waf1/Cip1)} up-regulation. We clarified the involvement of PKD1-related signaling on hCASMCs. Cultured hCASMCs, which constitutively express PKD1, were stimulated with 5% serum. Amlodipine increased p21{sup (Waf1/Cip1)} expression in a dose- and time-dependent manner, resulting in reduced hCASMC proliferation. The inhibitory effect of amlodipine was mimicked by overexpression of PKD1 and was reversed by a dominant-negative version of PKD1 (R4227X). Immunoblot analysis showed that phosphorylated JAK2 was increased by amlodipine treatment or PKD1 overexpression. A luciferase assay revealed that the overexpression of PKD1 induced STAT1 enhancer activity. These data suggest that PKD1 contributes to the antiproliferative effect of amlodipine on hCASMCs via JAK/STAT signaling and p21{sup (Waf1/Cip1)} up-regulation.

  16. Liver epithelial cells inhibit proliferation and invasiveness of hepatoma cells.

    PubMed

    Jeng, Kuo-Shyang; Jeng, Chi-Juei; Jeng, Wen-Juei; Sheen, I-Shyan; Li, Shih-Yun; Hung, Zih-Hang; Hsiau, Hsin-I; Yu, Ming-Che; Chang, Chiung-Fang

    2016-03-01

    Hepatocellular carcinoma (HCC) is a worldwide malignancy with poor prognosis. Liver progenitors or stem cells could be a potential therapy for HCC treatment since they migrate toward tumors. Rat liver epithelial (RLE) cells have both progenitor and stem cell-like properties. Therefore, our study elucidated the therapeutic effect of RLE cells in rat hepatoma cells. RLE cells were isolated from 10-day old rats and characterized for stem cell marker expression. RLE cells and rat hepatoma cells (H4-IIE-C3 cells) were co-cultured and divided into four groups with different ratios of RLE and hepatoma cells. Group A had only rat hepatoma cells as a control group. The ratios of rat hepatoma and RLE cells in group B, C and D were 5:1, 1:1 and 1:5, respectively. Effective inhibition of cell proliferation and migration was found in group D when compared to group A. There was a significant decrease in Bcl2 expression and increase in late apoptosis of rat hepatoma cells when adding more RLE cells. RLE cells reduced cell proliferation and migration of rat hepatoma cells. These results suggested that RLE cells could be used as a potential cell therapy. PMID:26647726

  17. Hydroxyurea treatment inhibits proliferation of Cryptococcus neoformans in mice.

    PubMed

    Tripathi, Kaushlendra; Mor, Visesato; Bairwa, Narendra K; Del Poeta, Maurizio; Mohanty, Bidyut K

    2012-01-01

    The fungal pathogen Cryptococcus neoformans (Cn) is a serious threat to immunocompromised individuals, especially for HIV patients who develop meningoencephalitis. For effective cryptococcal treatment, novel antifungal drugs or innovative combination therapies are needed. Recently, sphingolipids have emerged as important bioactive molecules in the regulation of microbial pathogenesis. Previously we reported that the sphingolipid pathway gene, ISC1, which is responsible for ceramide production, is a major virulence factor in Cn infection. Here we report our studies of the role of ISC1 during genotoxic stress induced by the antineoplastic hydroxyurea (HU) and methyl methanesulfonate (MMS), which affect DNA replication and genome integrity. We observed that Cn cells lacking ISC1 are highly sensitive to HU and MMS in a rich culture medium. HU affected cell division of Cn cells lacking the ISC1 gene, resulting in cell clusters. Cn ISC1, when expressed in a Saccharomyces cerevisiae (Sc) strain lacking its own ISC1 gene, restored HU resistance. In macrophage-like cells, although HU affected the proliferation of wild type (WT) Cn cells by 50% at the concentration tested, HU completely inhibited Cn isc1Δ cell proliferation. Interestingly, our preliminary data show that mice infected with WT or Cn isc1Δ cells and subsequently treated with HU had longer lifespans than untreated, infected control mice. Our work suggests that the sphingolipid pathway gene, ISC1, is a likely target for combination therapy with traditional drugs such as HU. PMID:22783238

  18. Metformin inhibits the proliferation of human prostate cancer PC-3 cells via the downregulation of insulin-like growth factor 1 receptor

    SciTech Connect

    Kato, Haruo Sekine, Yoshitaka; Furuya, Yosuke; Miyazawa, Yoshiyuki; Koike, Hidekazu; Suzuki, Kazuhiro

    2015-05-22

    Metformin is a biguanide drug that is widely used for the treatment of type 2 diabetes. Recent studies have shown that metformin inhibits cancer cell proliferation and tumor growth both in vitro and in vivo. The anti-tumor mechanisms of metformin include activation of the AMP-activated protein kinase/mTOR pathway and direct inhibition of insulin/insulin-like growth factor (IGF)-mediated cellular proliferation. However, the anti-tumor mechanism in prostate cancer remains unclear. Because activation of the IGF-1 receptor (IGF-1R) is required for prostate cell proliferation, IGF-1R inhibitors may be of therapeutic value. Accordingly, we examined the effects of metformin on IGF-1R signaling in prostate cancer cells. Metformin significantly inhibited PC-3 cell proliferation, migration, and invasion. IGF-1R mRNA expression decreased significantly after 48 h of treatment, and IGF-1R protein expression decreased in a similar manner. IGF-1R knockdown by siRNA transfection led to inhibited proliferation, migration and invasion of PC-3 cells. IGF-1 activated both ERK1/2 and Akt, but these effects were attenuated by metformin treatment. In addition, intraperitoneal treatment with metformin significantly reduced tumor growth and IGF-1R mRNA expression in PC-3 xenografts. Our results suggest that metformin is a potent inhibitor of the IGF-1/IGF-1R system and may be beneficial in prostate cancer treatment. - Highlights: • Metformin inhibited PC-3 cell proliferation, migration, and invasion. • Metformin decreased IGF-1R mRNA and protein expressions in PC-3 cells. • Metformin inhibited IGF-1 induced ERK and Akt phosphorylations in PC-3 cells. • Metformin treatment inhibited PC-3 cell growth and IGF-1R expression in vivo. • Metformin may be a potent inhibitor of the IGF-1/IGF-1R signaling.

  19. miR-150 inhibits terminal erythroid proliferation and differentiation

    PubMed Central

    Sun, Zhiwei; Wang, Ye; Han, Xu; Zhao, Xielan; Peng, Yuanliang; Li, Yusheng; Peng, Minyuan; Song, Jianhui; Wu, Kunlu; Sun, Shumin; Zhou, Weihua; Qi, Biwei; Zhou, Chufan; Chen, Huiyong; An, Xiuli; Liu, Jing

    2015-01-01

    MicroRNAs (miRNAs), a class of small non-coding linear RNAs, have been shown to play a crucial role in erythropoiesis. To evaluate the indispensable role of constant suppression of miR-150 during terminal erythropoiesis, we performed miR-150 gain- and loss-of-function experiments on hemin-induced K562 cells and EPO-induced human CD34+ cells. We found that forced expression of miR-150 suppresses commitment of hemoglobinization and CD235a labeling in both cell types. Erythroid proliferation is also inhibited via inducing apoptosis and blocking the cell cycle when miR-150 is overexpressed. In contrast, miR-150 inhibition promotes terminal erythropoiesis. 4.1 R gene is a new target of miR-150 during terminal erythropoiesis, and its abundance ensures the mechanical stability and deformability of the membrane. However, knockdown of 4.1 R did not affect terminal erythropoiesis. Transcriptional profiling identified more molecules involved in terminal erythroid dysregulation derived from miR-150 overexpression. These results shed light on the role of miR-150 during human terminal erythropoiesis. This is the first report highlighting the relationship between miRNA and membrane protein and enhancing our understanding of how miRNA works in the hematopoietic system. PMID:26543232

  20. Human peroxisome proliferator-activated receptor mRNA and protein expression during development

    EPA Science Inventory

    The peroxisome proliferator-activated receptors (PPAR) are nuclear hormone receptors that regulate lipid and glucose homeostasis and are important in reproduction and development. PPARs are targets ofpharmaceuticals and are also activated by environmental contaminants, including ...

  1. Toll-Like Receptor 2 Mediates Proliferation, Survival, NF-κB Translocation, and Cytokine mRNA Expression in LIF-Maintained Mouse Embryonic Stem Cells

    PubMed Central

    Taylor, Tammi; Kim, Young-June; Ou, Xuan; Derbigny, Wilbert

    2010-01-01

    Toll-like receptor (TLR) activation is important in immune responses and in differentiation of hematopoietic stem cells. We detected mRNA expression of TLRs 1, 2, 3, 5, and 6, but not TLRs 4, 7, 8, and 9 in murine (m)ESC line E14, and noted high cell surface protein expression of TLR2, but not TLR4, for mESC lines R1, CGR8, and E14. ESC lines were cultured in the presence of leukemia inhibitory factor (LIF). Pam3Cys enhanced proliferation and survival of the 3 ESC lines. In contrast, lipopolysaccharide (LPS) decreased proliferation and survival. Pam3Cys and LPS effects on proliferation and survival were blocked by antibody to TLR2, suggesting that effects of both Pam3Cys and LPS on these mESC lines were likely mediated through TLR2. E14 ESC line expressed MyD88. Pam3Cys stimulation of E14 ESCs was associated with induced NF-κB translocation, enhanced phosphorylation of IKK-α/β, and enhanced mRNA, but not protein, expression of tumor necrosis factor-α, interferon-γ, and IL-6. TLR2 activation by Pam3Cys or inhibition by LPS was not associated with changes in morphology or expression of alkaline phosphatase, Oct4, SSEA1, KLF4, or Sox2, markers of undifferentiated mESCs. Our studies identify TLR2 as present and functional in E14, R1, and CGR8 mESC lines. PMID:20132051

  2. Actein Inhibits Cell Proliferation and Migration in Human Osteosarcoma

    PubMed Central

    Chen, Zhi; Wu, Jingdong; Guo, Qinghao

    2016-01-01

    Background Osteosarcoma is one of the most common malignant bone cancers worldwide. Although the traditional chemotherapies have made some progression in the past decades, the mortality of osteosarcoma in children and adolescent is very high. Herein, the role of actein in osteosarcoma was explored. Material/Methods Cell viability assay was performed in osteosarcoma cell lines 143B and U2OS. Colony formation analysis was included when cells were treated with different doses of actin. Cell cycle assay was conducted to further examine the role of actein. Cell apoptotic rate and the relative activities of caspase-3, caspase-8, and caspase-9 were detected in 143B and U2OS osteosarcoma cells. Moreover, transwell assays were used to explore the effects of actein on cell metastasis. Results Actein significantly inhibited osteosarcoma cell viability in a time- and dose-dependent manner. Actein also dramatically suppressed the colony formation ability in osteosarcoma143B and U2OS cells. It was revealed that osteosarcoma cells were arrested in G0/G1 phase in the cell cycle progression and induced to apoptosis by administration of actein. The activities of pro-apoptotic factors such as caspase-3 and caspase-9 were significantly increased by actein. Furthermore, administration of actein decreased cell migrated and invasive abilities in both 143B and U2OS cell lines. Conclusions Actein inhibits tumor growth by inducing cell apoptosis in osteosarcoma. The inhibitive roles of actein in cell proliferation, migration and invasion suggest that actein may serve as a potential therapeutic agent in the treatment of osteosarcoma. PMID:27173526

  3. Inhibition of NF-kappaB stabilizes gadd45alpha mRNA.

    PubMed

    Zheng, Xue; Zhang, Yadong; Chen, Yu-Quan; Castranova, Vince; Shi, Xianglin; Chen, Fei

    2005-04-01

    Growth arrest- and DNA damage-inducible protein alpha (gadd45alpha) is an important regulator for cell cycle, genomic stability, and cell apoptosis. In the present report, we demonstrated that NF-kappaB inhibition due to Ikkbeta deficiency enhanced the stability of gadd45alpha mNRA. Using embryo fibroblast cells derived from wild type (wt) or Ikkbeta gene knockout (Ikkbeta(-/-)) mice, reverse transcription-polymerase chain reaction revealed a three- to fourfold increase of gadd45alpha mRNA in Ikkbeta(-/-) cells compared with wt cells. The deficiency in Ikkbeta substantially decreased basal NF-kappaB activity and increased accumulation of reactive oxygen species (ROS). However, such deficiency had no effect on the basal expression or activity of Akt, FoxO3a, p53, and c-myc that regulate the transcription of gadd45alpha gene positively or negatively. Analysis of gadd45alpha mRNA stability showed a ROS-dependent increase in the half-life of gadd45alpha mRNA in Ikkbeta(-/-) cells. Immunoprecipitation experiments indicated an increased binding of a RNA stabilizing protein, nucleolin, to gadd45alpha mRNA in Ikkbeta(-/-) cells. The binding of nucleolin to gadd45alpha mRNA could be prevented by the antioxidant, N-acetyl-cysteine. Thus, these data are the first to suggest that inhibition of Ikkbeta-NF-kappaB signaling up-regulates the expression of gadd45alpha mNRA through a post-transcriptional, rather than a transcriptional, mechanism. PMID:15721278

  4. Inhibition of CD25 (IL-2R alpha) expression and T-cell proliferation by polyclonal anti-thymocyte globulins.

    PubMed Central

    Bonnefoy-Berard, N; Verrier, B; Vincent, C; Revillard, J P

    1992-01-01

    Anti-lymphocyte and anti-thymocyte globulins (ATG) are currently used as immunosuppressive agents in organ transplantation. Their administration in vivo may induce not only lymphocyte depletion but also functional effects which were investigated in the present study. In vitro ATG inhibited T-cell proliferation induced by monocyte-dependent T-cell mitogens, like CD3 antibodies, phytohaemagglutinin (PHA) and concanavalin A (Con A), by monocyte-independent mitogens, like CD2 antibodies, or by protein kinase C activators (phorbol esters) associated with a calcium ionophore. The inhibitory effect of ATG was therefore not solely accounted for by a suppression of co-stimulatory signals delivered by monocytes, but rather implied a direct action on T cells. Addition of recombinant human interleukin-2 (rIL-2) did not overcome the inhibition. Suppression of T-cell proliferation by ATG was characterized by normal RNA synthesis and IL-2 secretion contrasting with markedly reduced expression of the CD25 protein [p55, the alpha-chain of interleukin-2 receptor (IL-2R)] both in cytoplasm and on T-cell membrane, as well as a decreased secretion of interferon-gamma (IFN-gamma). Northern blot analysis revealed increased levels of CD25 and IFN-gamma mRNA, suggesting a post-transcriptional inhibition of these molecules, whereas IL-2 mRNA levels were unchanged. These data demonstrate that inhibition of T-cell proliferation by ATG can be attributed primarily to a post-transcriptional defect of CD25 expression, implying a novel mechanism different from those described with other immunosuppressive agents. Blocking of T-cell proliferation in the late G1 phase of the cell cycle may contribute to the immunosuppressive activity of ATG in prophylactic treatment of allograft rejection. Images Figure 2 PMID:1398765

  5. Diosgenin relieves goiter via the inhibition of thyrocyte proliferation in a mouse model of Graves' disease

    PubMed Central

    Cai, Hu; Wang, Zhe; Zhang, Hai-qing; Wang, Fu-rong; Yu, Chun-xiao; Zhang, Feng-xia; Gao, Ling; Zhang, Jian; Zhao, Jia-jun

    2014-01-01

    Aim: To investigate the effects of diosgenin (Dio), a naturally occurring steroid saponin, on goiter formation in a mouse model of Graves' disease (GD) and the underlying mechanisms. Methods: Female BALB/c mice were injected with adenovirus expressing the A subunit of thyrotropin receptor to induce GD. The mice were treated with Dio (20, 100 mg·kg−1·d−1, ip) for 12 or 24 d. The serum levels of TT4 and TRAb were examined using radioimmunoassay and electrochemiluminescence. The size and morphology of thyroid glands were examined. Thyrocyte proliferation was determined using BrdU incorporation assay. The expression of proliferation-associated proteins IGF-1, NF-κB, cyclin D1, and PCNA in thyroids was analyzed using immunohistochemistry and real-time PCR. Results: The GD mice showed significantly high serum levels of TRAb and TT4 compared to the normal mice. Treatment of the GD mice with Dio for 24 d dose-dependently reduced the TT4 level and thyroid size, but did not affect the abnormal level of TRAb. Furthermore, Dio treatment dose-dependently reversed the morphological changes and reduced excessive thyrocyte proliferation in thyroids of the GD mice. Dio treatment also dose-dependently reduced the mRNA and protein levels of IGF-1, NF-κB, cyclin D1, and PCNA in thyroids of the GD mice. Conclusion: Dio relieves goiter in a mouse model of GD through the inhibition of thyrocyte proliferation. The mechanisms involve the suppression of IGF-1, NF-κB, cyclin D1, and PCNA expression. PMID:24241350

  6. Delphinidin prevents high glucose-induced cell proliferation and collagen synthesis by inhibition of NOX-1 and mitochondrial superoxide in mesangial cells.

    PubMed

    Song, Seung Eun; Jo, Hye Jun; Kim, Yong-Woon; Cho, Young-Je; Kim, Jae-Ryong; Park, So-Young

    2016-04-01

    This study examined the effect of delphinidin on high glucose-induced cell proliferation and collagen synthesis in mesangial cells. Glucose dose-dependently (5.6-25 mM) increased cell proliferation and collagen I and IV mRNA levels, whereas pretreatment with delphinidin (50 μM) prevented cell proliferation and the increased collagen mRNA levels induced by high glucose (25 mM). High glucose increased reactive oxygen species (ROS) generation, and this was suppressed by pretreating delphinidin or the antioxidant N-acetyl cysteine. NADPH oxidase (NOX) 1 was upregulated by high glucose, but pretreatment with delphinidin abrogated this upregulation. Increased mitochondrial superoxide by 25 mM glucose was also suppressed by delphinidin. The NOX inhibitor apocynin and mitochondria-targeted antioxidant Mito TEMPO inhibited ROS generation and cell proliferation induced by high glucose. Phosphorylation of extracellular signal regulated kinase (ERK)1/2 was increased by high glucose, which was suppressed by delphinidin, apocynin or Mito TEMPO. Furthermore, PD98059 (an ERK1/2 inhibitor) prevented the high glucose-induced cell proliferation and increased collagen mRNA levels. Transforming growth factor (TGF)-β protein levels were elevated by high glucose, and pretreatment with delphinidin or PD98059 prevented this augmentation. These results suggest that delphinidin prevents high glucose-induced cell proliferation and collagen synthesis by inhibition of NOX-1 and mitochondrial superoxide in mesangial cells. PMID:27103328

  7. Prostacyclin Analogue Beraprost Inhibits Cardiac Fibroblast Proliferation Depending on Prostacyclin Receptor Activation through a TGF β-Smad Signal Pathway

    PubMed Central

    Yao, Wenjuan; Zhu, Hongyan; Xu, Xiaole; Meng, Guoliang; Zhang, Wei

    2014-01-01

    Previous studies showed that prostacyclin inhibited fibrosis. However, both receptors of prostacyclin, prostacyclin receptor (IP) and peroxisome proliferator-activated receptor (PPAR), are abundant in cardiac fibroblasts. Here we investigated which receptor was vital in the anti-fibrosis effect of prostacyclin. In addition, the possible mechanism involved in protective effects of prostacyclin against cardiac fibrosis was also studied. We found that beraprost, a prostacyclin analogue, inhibited angiotensin II (Ang II)-induced neonatal rat cardiac fibroblast proliferation in a concentration-dependent and time-dependent manner. Beraprost also suppressed Ang II-induced collagen I mRNA expression and protein synthesis in cardiac fibroblasts. After IP expression was knocked down by siRNA, Ang II-induced proliferation and collagen I synthesis could no longer be rescued by beraprost. However, treating cells with different specific inhibitors of PPAR subtypes prior to beraprost and Ang II stimulation, all of the above attenuating effects of beraprost were still available. Moreover, beraprost significantly blocked transforming growth factor β (TGF β) expression as well as Smad2 phosphorylation and reduced Smad-DNA binding activity. Beraprost also increased phosphorylation of cAMP response element binding protein (CREB) at Ser133 in the nucleus. Co-immunoprecipitation analysis revealed that beraprost increased CREB but decreased Smad2 binding to CREB-binding protein (CBP) in nucleus. In conclusion, beraprost inhibits cardiac fibroblast proliferation by activating IP and suppressing TGF β-Smad signal pathway. PMID:24852754

  8. Regulation of PMP22 mRNA by G3BP1 affects cell proliferation in breast cancer cells

    PubMed Central

    2013-01-01

    Background Regulation of mRNAs is one way to control protein levels and thereby important cellular processes such as growth, invasion and apoptosis. G3BPs constitute a family of mRNA-binding proteins, shown to be overexpressed in several cancer types, including breast, colon and pancreas cancer. G3BP has been reported to both stabilize and induce degradation of specific mRNAs. Results Here, we show that G3BP1, but not G3BP2, supports proliferation of several breast cancer cell lines. Global gene expression analyses of G3BP1- and G3BP2-depleted cells indicate that primarily G3BP1, and much less G3BP2, influences mRNA expression levels. Peripheral myelin protein 22 (PMP22) was one gene that was significantly influenced by G3BP1 depletion which led to a 2–3 fold increased expression. Depletion of PMP22 resulted in increased proliferation and the G3BP1-mediated effect on proliferation was not seen upon PMP22-depletion. Conclusions This indicates a novel role for G3BP1 in the regulation of cell proliferation in breast cancer cells, perhaps via a regulatory effect on PMP22 expression. PMID:24321297

  9. Dehydroepiandrosterone inhibits cell proliferation and improves viability by regulating S phase and mitochondrial permeability in primary rat Leydig cells

    PubMed Central

    LIU, LIN; WANG, DIAN; LI, LONGLONG; DING, XIAO; MA, HAITIAN

    2016-01-01

    Dehydroepiandrosterone (DHEA) is widely used as a nutritional supplement and exhibits putative anti-aging properties. However, the molecular basis of the actions of DHEA, particularly on the biological characteristics of target cells, remain unclear. The aim of the current study was to investigate the effects of DHEA on cell viability, cell proliferation, cell cycle and mitochondrial function in primary rat Leydig cells. Adult Leydig cells were purified by Percoll gradient centrifugation, and cell proliferation was detected using a Click-iT® EdU Assay kit and cell cycle assessment performed using flow cytometry. Mitochondrial membrane potential was detected using JC-1 staining assay. The results of the current study demonstrate that DHEA decreased cell proliferation in a dose-dependent manner, whereas it improved cell viability in a time-dependent and dose-dependent manner. Flow cytometry analysis demonstrated that DHEA treatment increased the S phase cell population and decreased the G2/M cell population. Cyclin A and CDK2 mRNA levels were decreased in primary rat Leydig cells following DHEA treatment. DHEA treatment decreased the transmembrane electrical gradient in primary Leydig cells, whereas treatment significantly increased succinate dehydrogenase activity. These results indicated that DHEA inhibits primary rat Leydig cell proliferation by decreasing cyclin mRNA level, whereas it improves cells viability by modulating the permeability of the mitochondrial membrane and succinate dehydrogenase activity. These findings may demonstrate an important molecular mechanism by which DHEA activity is mediated. PMID:27220727

  10. Dehydroepiandrosterone inhibits cell proliferation and improves viability by regulating S phase and mitochondrial permeability in primary rat Leydig cells.

    PubMed

    Liu, Lin; Wang, Dian; Li, Longlong; Ding, Xiao; Ma, Haitian

    2016-07-01

    Dehydroepiandrosterone (DHEA) is widely used as a nutritional supplement and exhibits putative anti‑aging properties. However, the molecular basis of the actions of DHEA, particularly on the biological characteristics of target cells, remain unclear. The aim of the current study was to investigate the effects of DHEA on cell viability, cell proliferation, cell cycle and mitochondrial function in primary rat Leydig cells. Adult Leydig cells were purified by Percoll gradient centrifugation, and cell proliferation was detected using a Click-iT® EdU Assay kit and cell cycle assessment performed using flow cytometry. Mitochondrial membrane potential was detected using JC-1 staining assay. The results of the current study demonstrate that DHEA decreased cell proliferation in a dose‑dependent manner, whereas it improved cell viability in a time‑dependent and dose‑dependent manner. Flow cytometry analysis demonstrated that DHEA treatment increased the S phase cell population and decreased the G2/M cell population. Cyclin A and CDK2 mRNA levels were decreased in primary rat Leydig cells following DHEA treatment. DHEA treatment decreased the transmembrane electrical gradient in primary Leydig cells, whereas treatment significantly increased succinate dehydrogenase activity. These results indicated that DHEA inhibits primary rat Leydig cell proliferation by decreasing cyclin mRNA level, whereas it improves cells viability by modulating the permeability of the mitochondrial membrane and succinate dehydrogenase activity. These findings may demonstrate an important molecular mechanism by which DHEA activity is mediated. PMID:27220727

  11. The Consensus 5' Splice Site Motif Inhibits mRNA Nuclear Export

    PubMed Central

    Lee, Eliza S.; Akef, Abdalla; Mahadevan, Kohila; Palazzo, Alexander F.

    2015-01-01

    In eukaryotes, mRNAs are synthesized in the nucleus and then exported to the cytoplasm where they are translated into proteins. We have mapped an element, which when present in the 3’terminal exon or in an unspliced mRNA, inhibits mRNA nuclear export. This element has the same sequence as the consensus 5’splice site motif that is used to define the start of introns. Previously it was shown that when this motif is retained in the mRNA, it causes defects in 3’cleavage and polyadenylation and promotes mRNA decay. Our new data indicates that this motif also inhibits nuclear export and promotes the targeting of transcripts to nuclear speckles, foci within the nucleus which have been linked to splicing. The motif, however, does not disrupt splicing or the recruitment of UAP56 or TAP/Nxf1 to the RNA, which are normally required for nuclear export. Genome wide analysis of human mRNAs, lncRNA and eRNAs indicates that this motif is depleted from naturally intronless mRNAs and eRNAs, but less so in lncRNAs. This motif is also depleted from the beginning and ends of the 3’terminal exons of spliced mRNAs, but less so for lncRNAs. Our data suggests that the presence of the 5’splice site motif in mature RNAs promotes their nuclear retention and may help to distinguish mRNAs from misprocessed transcripts and transcriptional noise. PMID:25826302

  12. [Knockdown of angiopoietin-like protein 4 inhibits proliferation and promotes apoptosis in cervical cancer SiHa cells].

    PubMed

    Nie, Dan; Liu, Ling; Xia, Jiyi; Wang, Chunyan; Zhan, Ping; Mao, Xiguang

    2016-04-01

    Objective To investigate the effect of lentivirus-mediated shRNA silencing of angiopoietin-like protein 4 (ANGPTL4) on the proliferation and apoptosis of cervical cancer SiHa cells. Methods The ANGPTL4 lentiviral vectors were used to transfect SiHa cells. Real-time quantitative PCR (qRT-PCR) and Western blotting were respectively used to detect ANGPTL4 expression at mRNA and protein levels. The proliferation ability of SiHa cells after transfection was assessed by MTT assay and colony formation assay. The cell cycle was examined by flow cytometry. The annexin V-phycoerythrin/7-aminoactinomycin D (annexin V-PE/7-AAD) staining combined with flow cytometry was used to examine the effect of ANGPTL4 silence on the apoptosis of SiHa cells. Results After the ANGPTL4 lentiviral vectors were transfected into SiHa cells, qRT-PCR and Western blotting showed that the expression of ANGPTL4 mRNA and protein were significantly inhibited in LV3-ANGPTL4 group. The MTT assay showed that the proliferation ability of SiHa cells in LV3-ANGPTL4 group was also inhibited. Colony formation assay revealed that the colony number in LV3-ANGPTL4 group was reduced. The cells in G0/G1 phase and the apoptosis rate increased in LV3-ANGPTL4 group. Conclusion The lentivirus-mediated ANGPTL4 shRNA can inhibit the proliferation, induce the cell cycle arrest in G0/G1 phase, and promote the apoptosis in SiHa cells. PMID:27053616

  13. Inhibition of vaccinia mRNA methylation by 2',5'-linked oligo(adenylic acid) triphosphate

    SciTech Connect

    Sharma, O.K.; Goswami, B.B.

    1981-04-01

    Extracts of interferon-treated cells synthesize unique 2',5'-linked oligo(adenylic acid) 5'-phosphates in the presence of ATP and double-stranded RNA. 2',5'-linked oligo(adenylic acid) 5'-triphosphate inhibits protein synthesis at nanomolar concentrations by activating RNase. We have observed that oligo(adenylic acid) 5'-monophosphate and 5'-triphosphate are potent inhibitors of vaccinia mRNA methylation in vitro. Both the methylation of the 5'-terminal guanine at the 7 position and the 2'-O-ribose methylation of the penultimate nucleoside are inhibited. Such inhibition of mRNA methylation is not due to degradation of the mRNA. Inhibition of the requisite modification of the 5' terminus of mRNA by 2',5'-linked oligo(adenylic acids) may be a mechanism of interferon action against both DNA and RNA viruses in which mRNAs derived from them are capped.

  14. Overexpression of Tau Downregulated the mRNA Levels of Kv Channels and Improved Proliferation in N2A Cells

    PubMed Central

    Li, Xiantao; Hu, Ximu; Li, Xiaoqing; Hao, Xuran

    2015-01-01

    Microtubule binding protein tau has a crucial function in promoting the assembly and stabilization of microtubule. Besides tuning the action potentials, voltage-gated K+ channels (Kv) are important for cell proliferation and appear to play a role in the development of cancer. However, little is known about the possible interaction of tau with Kv channels in various tissues. In the present study, tau plasmids were transiently transfected into mouse neuroblastoma N2A cells to explore the possible linkages between tau and Kv channels. This treatment led to a downregulation of mRNA levels of several Kv channels, including Kv2.1, Kv3.1, Kv4.1, Kv9.2, and KCNH4, but no significant alteration was observed for Kv5.1 and KCNQ4. Furthermore, the macroscopic currents through Kv channels were reduced by 36.5% at +60 mV in tau-tranfected N2A cells. The proliferation rates of N2A cells were also improved by the induction of tau expression and the incubation of TEA (tetraethylammonium) for 48 h by 120.9% and 149.3%, respectively. Following the cotransfection with tau in HEK293 cells, the mRNA levels and corresponding currents of Kv2.1 were significantly declined compared with single Kv2.1 transfection. Our data indicated that overexpression of tau declined the mRNA levels of Kv channels and related currents. The effects of tau overexpression on Kv channels provided an alternative explanation for low sensitivity to anti-cancer chemicals in some specific cancer tissues. PMID:25590133

  15. Inhibition of pyrimidine synthesis reverses viral virulence factor-mediated block of mRNA nuclear export

    PubMed Central

    Zhang, Liang; Das, Priyabrata; Schmolke, Mirco; Manicassamy, Balaji; Wang, Yaming; Deng, Xiaoyi; Cai, Ling; Tu, Benjamin P.; Forst, Christian V.; Roth, Michael G.; Levy, David E.; García-Sastre, Adolfo; de Brabander, Jef; Phillips, Margaret A.

    2012-01-01

    The NS1 protein of influenza virus is a major virulence factor essential for virus replication, as it redirects the host cell to promote viral protein expression. NS1 inhibits cellular messenger ribonucleic acid (mRNA) processing and export, down-regulating host gene expression and enhancing viral gene expression. We report in this paper the identification of a nontoxic quinoline carboxylic acid that reverts the inhibition of mRNA nuclear export by NS1, in the absence or presence of the virus. This quinoline carboxylic acid directly inhibited dihydroorotate dehydrogenase (DHODH), a host enzyme required for de novo pyrimidine biosynthesis, and partially reduced pyrimidine levels. This effect induced NXF1 expression, which promoted mRNA nuclear export in the presence of NS1. The release of NS1-mediated mRNA export block by DHODH inhibition also occurred in the presence of vesicular stomatitis virus M (matrix) protein, another viral inhibitor of mRNA export. This reversal of mRNA export block allowed expression of antiviral factors. Thus, pyrimidines play a necessary role in the inhibition of mRNA nuclear export by virulence factors. PMID:22312003

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

    PubMed Central

    2013-01-01

    Background SPARC is a matricellular glycoprotein with growth-inhibitory and antiangiogenic activity in some cell types. The study of this protein in hematopoietic malignancies led to conflicting reports about its role as a tumor suppressor or promoter, depending on its different functions in the tumor microenvironment. In this study we investigated the variations in SPARC production by peripheral blood cells from chronic myeloid leukemia (CML) patients at diagnosis and after treatment and we identified the subpopulation of cells that are the prevalent source of SPARC. Methods We evaluated SPARC expression using real-time PCR and western blotting. SPARC serum levels were detected by ELISA assay. Finally we analyzed the interaction between exogenous SPARC and imatinib (IM), in vitro, using ATP-lite and cell cycle analysis. Results Our study shows that the CML cells of patients at diagnosis have a low mRNA and protein expression of SPARC. Low serum levels of this protein are also recorded in CML patients at diagnosis. However, after IM treatment we observed an increase of SPARC mRNA, protein, and serum level in the peripheral blood of these patients that had already started at 3 months and was maintained for at least the 18 months of observation. This SPARC increase was predominantly due to monocyte production. In addition, exogenous SPARC protein reduced the growth of K562 cell line and synergized in vitro with IM by inhibiting cell cycle progression from G1 to S phase. Conclusion Our results suggest that low endogenous SPARC expression is a constant feature of BCR/ABL positive cells and that IM treatment induces SPARC overproduction by normal cells. This exogenous SPARC may inhibit CML cell proliferation and may synergize with IM activity against CML. PMID:23383963

  17. Naltrindole inhibits human multiple myeloma cell proliferation in vitro and in a murine xenograft model in vivo.

    PubMed

    Mundra, Jyoti Joshi; Terskiy, Alexandra; Howells, Richard D

    2012-08-01

    It has been demonstrated previously that immune cell activation and proliferation were sensitive to the effects of naltrindole, a nonpeptidic δ-opioid receptor-selective antagonist; therefore, we hypothesized that human multiple myeloma (MM) would be a valuable model for studying potential antineoplastic properties of naltrindole. [(3)H]naltrindole exhibited saturable, low-affinity binding to intact human MM cells; however, the pharmacological profile of the binding site differed considerably from the properties of δ-, κ-, and μ-opioid receptors, and opioid receptor mRNA was not detected in MM cells by reverse transcriptase-polymerase chain reaction. Naltrindole inhibited the proliferation of cultured human U266 MM cells in a time- and dose-dependent manner with an EC(50) of 16 μM. The naltrindole-induced inhibition of U266 cell proliferation was not blocked by a 10-fold molar excess of naltrexone, a nonselective opioid antagonist. Additive inhibition of MM cell proliferation was observed when using a combination of naltrindole with the histone deacetylase inhibitor sodium valproate, the proteasome inhibitor bortezomib, the glucocorticoid receptor agonist dexamethasone, and the HMG CoA reductase inhibitor simvastatin. Treatment of U266 cells with naltrindole significantly decreased the level of the active, phosphorylated form of the kinases, extracellular signal-regulated kinase and Akt, which may be related to its antiproliferative activity. The antiproliferative activity of naltrindole toward MM cells was maintained in cocultures of MM and bone marrow-derived stromal cells, mimicking the bone marrow microenvironment. In vivo, naltrindole significantly decreased tumor cell volumes in human MM cell xenografts in severe combined immunodeficient mice. We hypothesize that naltrindole inhibits the proliferation of MM cells through a nonopioid receptor-dependent mechanism. PMID:22537770

  18. Naltrindole Inhibits Human Multiple Myeloma Cell Proliferation In Vitro and in a Murine Xenograft Model In Vivo

    PubMed Central

    Mundra, Jyoti Joshi; Terskiy, Alexandra

    2012-01-01

    It has been demonstrated previously that immune cell activation and proliferation were sensitive to the effects of naltrindole, a nonpeptidic δ-opioid receptor-selective antagonist; therefore, we hypothesized that human multiple myeloma (MM) would be a valuable model for studying potential antineoplastic properties of naltrindole. [3H]naltrindole exhibited saturable, low-affinity binding to intact human MM cells; however, the pharmacological profile of the binding site differed considerably from the properties of δ-, κ-, and μ-opioid receptors, and opioid receptor mRNA was not detected in MM cells by reverse transcriptase-polymerase chain reaction. Naltrindole inhibited the proliferation of cultured human U266 MM cells in a time- and dose-dependent manner with an EC50 of 16 μM. The naltrindole-induced inhibition of U266 cell proliferation was not blocked by a 10-fold molar excess of naltrexone, a nonselective opioid antagonist. Additive inhibition of MM cell proliferation was observed when using a combination of naltrindole with the histone deacetylase inhibitor sodium valproate, the proteasome inhibitor bortezomib, the glucocorticoid receptor agonist dexamethasone, and the HMG CoA reductase inhibitor simvastatin. Treatment of U266 cells with naltrindole significantly decreased the level of the active, phosphorylated form of the kinases, extracellular signal-regulated kinase and Akt, which may be related to its antiproliferative activity. The antiproliferative activity of naltrindole toward MM cells was maintained in cocultures of MM and bone marrow-derived stromal cells, mimicking the bone marrow microenvironment. In vivo, naltrindole significantly decreased tumor cell volumes in human MM cell xenografts in severe combined immunodeficient mice. We hypothesize that naltrindole inhibits the proliferation of MM cells through a nonopioid receptor-dependent mechanism. PMID:22537770

  19. Hispidulin inhibits proliferation and enhances chemosensitivity of gallbladder cancer cells by targeting HIF-1α

    SciTech Connect

    Gao, Hui; Xie, Jing; Peng, Jianjun; Han, Yantao; Jiang, Qixiao; Han, Mei; Wang, Chunbo

    2015-03-15

    Gallbladder cancer (GBC) is an aggressive malignancy of the bile duct, which is associated with a low (5-year) survival and poor prognosis. The transcription factor HIF-1α is implicated in the angiogenesis, cell survival, epithelial mesenchymal transition (EMT) and invasiveness of GBC. In this study, we have investigated the role of HIF-1α in the pathobilogy of GBC and effect of hispidulin on the molecular events controlled by this transcription factor. We observed that hispidulin caused induction of apoptosis, blockade of growth and cell cycle progression in GBC cells. Our results have demonstrated for the first time that hispidulin-exerted anti-tumor effect involved the suppression of HIF-1α signaling. Hispidulin was found to repress the expression of HIF-1α protein dose-dependently without affecting the HIF-1α mRNA expression. In addition, the inhibition of HIF-1α protein synthesis was revealed to be mediated through the activation of AMPK signaling. Hispidulin also sensitized the tumor cells to Gemcitabine and 5-Fluoroucil by down-regulating HIF-1α/P-gp signaling. Given the low cost and exceedingly safe profile, hispidulin appears to be a promising and novel chemosensitizer for GBC treatment. - Highlights: • Hispidulin inhibits proliferation of gallbladder cancer cells by targeting HIF-1α. • Hispidulin regulates HIF-1α via activating AMPK signaling. • Hispidulin sensitized the GBC cells to chemotherapeutics by down-regulating P-gp.

  20. Vesnarinone suppresses TNFα mRNA expression by inhibiting valosin-containing protein.

    PubMed

    Hotta, Kentaro; Nashimoto, Akihiro; Yasumura, Eiji; Suzuki, Masafumi; Azuma, Motoki; Iizumi, Yosuke; Shima, Daisuke; Nabeshima, Ryusuke; Hiramoto, Masaki; Okada, Akira; Sakata-Sogawa, Kumiko; Tokunaga, Makio; Ito, Takumi; Ando, Hideki; Sakamoto, Satoshi; Kabe, Yasuaki; Aizawa, Shinichi; Imai, Takeshi; Yamaguchi, Yuki; Watanabe, Hajime; Handa, Hiroshi

    2013-05-01

    Vesnarinone is a synthetic quinolinone derivative used in the treatment of cardiac failure and cancer. It is also known to cause agranulocytosis as a side effect, which restricts its use, although the mechanism underlying agranulocytosis is not well understood. Here, we show that vesnarinone binds to valosin-containing protein (VCP), which interacts with polyubiquitinated proteins and is essential for the degradation of IκBα to activate nuclear factor (NF)κB. We show that vesnarinone impairs the degradation of IκBα, and that the impairment of the degradation of IκBα is the result of the inhibition of the interaction between VCP and the 26S proteasome by vesnarinone. These results suggest that vesnarinone suppresses NFκB activation by inhibiting the VCP-dependent degradation of polyubiquitinated IκBα, resulting in the suppression of tumor necrosis factor-α mRNA expression. PMID:23393163

  1. Arginase inhibition reduces interleukin-1β-stimulated vascular smooth muscle cell proliferation by increasing nitric oxide synthase-dependent nitric oxide production

    SciTech Connect

    Yoon, Jeongyeon; Ryoo, Sungwoo

    2013-06-07

    Highlights: •Arginase inhibition suppressed proliferation of IL-1β-stimulated VSMCs in dose-dependent manner. •NO production from IL-1β-induced iNOS expression was augmented by arginase inhibition, reducing VSMC proliferation. •Incubation with cGMP analogues abolished IL-1β-dependent proliferation of VSMCs. -- Abstract: We investigated whether arginase inhibition suppressed interleukin (IL)-1β-stimulated proliferation in vascular smooth muscle cells (VSMCs) and the possible mechanisms involved. IL-1β stimulation increased VSMC proliferation, while the arginase inhibitor BEC and transfection of the antisense (AS) oligonucleotide against arginase I decreased VSMC proliferation and was associated with increased protein content of the cell cycle regulator p21Waf1/Cip1. IL-1β incubation induced inducible nitric oxide synthase (iNOS) mRNA expression and protein levels in a dose-dependent manner, but did not affect arginase I and II expression. Consistent with this data, IL-1β stimulation resulted in increase in NO production that was significantly augmented by arginase inhibition. The specific iNOS inhibitor 1400W abolished IL-1β-mediated NO production and further accentuated IL-1β-stimulated cell proliferation. Incubation with NO donors GSNO and DETA/NO in the presence of IL-1β abolished VSMCs proliferation and increased p21Waf1/Cip1 protein content. Furthermore, incubation with the cGMP analogue 8-Br-cGMP prevented IL-1β-induced VSMCs proliferation. In conclusion, arginase inhibition augmented iNOS-dependent NO production that resulted in suppression of IL-1β-induced VSMCs proliferation in a cGMP-dependent manner.

  2. Myocardin inhibits cellular proliferation by inhibiting NF-kappaB(p65)-dependent cell cycle progression.

    PubMed

    Tang, Ru-Hang; Zheng, Xi-Long; Callis, Thomas E; Stansfield, William E; He, Jiayin; Baldwin, Albert S; Wang, Da-Zhi; Selzman, Craig H

    2008-03-01

    We previously reported the importance of the serum response factor (SRF) cofactor myocardin in controlling muscle gene expression as well as the fundamental role for the inflammatory transcription factor NF-kappaB in governing cellular fate. Inactivation of myocardin has been implicated in malignant tumor growth. However, the underlying mechanism of myocardin regulation of cellular growth remains unclear. Here we show that NF-kappaB(p65) represses myocardin activation of cardiac and smooth muscle genes in a CArG-box-dependent manner. Consistent with their functional interaction, p65 directly interacts with myocardin and inhibits the formation of the myocardin/SRF/CArG ternary complex in vitro and in vivo. Conversely, myocardin decreases p65-mediated target gene activation by interfering with p65 DNA binding and abrogates LPS-induced TNF-alpha expression. Importantly, myocardin inhibits cellular proliferation by interfering with NF-kappaB-dependent cell-cycle regulation. Cumulatively, these findings identify a function for myocardin as an SRF-independent transcriptional repressor and cell-cycle regulator and provide a molecular mechanism by which interaction between NF-kappaB and myocardin plays a central role in modulating cellular proliferation and differentiation. PMID:18296632

  3. Evodiamine inhibits the proliferation of leukemia cell line K562 by regulating peroxisome proliferators-activated receptor gamma (PPARγ) pathway.

    PubMed

    Sun, Chengming; Zhang, Guili; Luan, Shuping; Luan, Caifu; Shao, Huiyuan; Dong, Fei; Liu, Xuena

    2016-08-01

    Evodiamine, a quinolone alkaloid, is one of the major bioactive compounds of Evodia rutaecarpa Bentham (Rutaceae). It exhibits excellent biological activities, especially the anticancer activity. This study aims to investigate the effect of evodiamine on the proliferation of leukemia cell line K562 and to explore the underlying mechanism. The effect of evodiamine on K562 cells proliferation was analyzed by trypan blue dye exclusion assay and MTT assay. The expression levels of peroxisome proliferators-activated receptor gamma (PPARγ), cyclin D1, and p21 were detected by western blot assay. The results demonstrated that evodiamine inhibited the proliferation and decreased the viability of K562 cells in a dose- and time-dependent manner. 2-Chloro-5-nitro-N-phenylbenzamide (GW9662) and/or PPARγ-siRNA pretreatment alleviated the cell growth suppression triggered by evodiamine. Meanwhile, evodiamine intervention elevated the expression of PPARγ in K562 cells, while pretreatment with GW9662 attenuated the enhanced upregulation of PPARγ expression induced by evodiamine. In addition, GW9662 and PPARγ-siRNA pretreatment also significantly attenuated the downregulation of the cell cycle control protein cyclin D1 and the upregulation of cyclin-dependent kinase inhibitor p21 induced by evodiamine. In conclusion, PPARγ signaling pathway may involve in the proliferation inhibition of evodiamine on K562 cells via inhibiting cylcin D1 and stimulating of p21. PMID:26671528

  4. Suberoylanilide hydroxamic acid (SAHA) inhibits EGF-induced cell transformation via reduction of cyclin D1 mRNA stability

    SciTech Connect

    Zhang, Jingjie; Ouyang, Weiming; Li, Jingxia; Zhang, Dongyun; Yu, Yonghui; Wang, York; Li, Xuejun; Huang, Chuanshu

    2012-09-01

    Suberoylanilide hydroxamic acid (SAHA) inhibiting cancer cell growth has been associated with its downregulation of cyclin D1 protein expression at transcription level or translation level. Here, we have demonstrated that SAHA inhibited EGF-induced Cl41 cell transformation via the decrease of cyclin D1 mRNA stability and induction of G0/G1 growth arrest. We found that SAHA treatment resulted in the dramatic inhibition of EGF-induced cell transformation, cyclin D1 protein expression and induction of G0/G1 growth arrest. Further studies showed that SAHA downregulation of cyclin D1 was only observed with endogenous cyclin D1, but not with reconstitutionally expressed cyclin D1 in the same cells, excluding the possibility of SAHA regulating cyclin D1 at level of protein degradation. Moreover, SAHA inhibited EGF-induced cyclin d1 mRNA level, whereas it did not show any inhibitory effect on cyclin D1 promoter-driven luciferase reporter activity under the same experimental conditions, suggesting that SAHA may decrease cyclin D1 mRNA stability. This notion was supported by the results that treatment of cells with SAHA decreased the half-life of cyclin D1 mRNA from 6.95 h to 2.57 h. Consistent with downregulation of cyclin D1 mRNA stability, SAHA treatment also attenuated HuR expression, which has been well-characterized as a positive regulator of cyclin D1 mRNA stability. Thus, our study identifies a novel mechanism responsible for SAHA inhibiting cell transformation via decreasing cyclin D1 mRNA stability and induction of G0/G1 growth arrest in Cl41 cells. -- Highlights: ► SAHA inhibits cell transformation in Cl41 cells. ► SAHA suppresses Cyclin D1 protein expression. ► SAHA decreases cyclin D1 mRNA stability.

  5. Nitro-linoleic acid inhibits vascular smooth muscle cell proliferation via the Keap1/Nrf2 signaling pathway

    PubMed Central

    Villacorta, Luis; Zhang, Jifeng; Garcia-Barrio, Minerva T.; Chen, Xi-lin; Freeman, Bruce A.; Chen, Yuqing E.; Cui, Taixing

    2007-01-01

    Nitroalkenes, the nitration products of unsaturated fatty acids formed via NO-dependent oxidative reactions, have been demonstrated to exert strong biological actions in endothelial cells and monocytes/macrophages; however, little is known about their effects on vascular smooth muscle cells (VSMCs). The present study examined the role of nitro-linoleic acid (LNO2) in the regulation of VSMC proliferation. We observed that LNO2 inhibited VSMC proliferation in a dose-dependent manner. In addition, LNO2 induced growth arrest of VSMCs in the G1/S phase of the cell cycle with an upregulation of the cyclin-dependent kinase inhibitor p27kip1. Furthermore, LNO2 triggered nuclear factor-erythroid 2-related factor 2 (Nrf2) nuclear translocation and activation of the antioxidant-responsive element-driven transcriptional activity via impairing Kelch-like ECH-associating protein 1 (Keap1)-mediated negative control of Nrf2 activity in VSMCs. LNO2 upregulated the expression of Nrf2 protein levels, but not mRNA levels, in VSMCs. A forced activation of Nrf2 led to an upregulation of p27kip1 and growth inhibition of VSMCs. In contrast, knock down of Nrf2 using an Nrf2 siRNA approach reversed the LNO2-induced upregulation of p27kip1 and inhibition of cellular proliferation in VSMCs. These studies provide the first evidence that nitroalkene LNO2 inhibits VSMC proliferation through activation of the Keap1/Nrf2 signaling pathway, suggesting an important role of nitroalkenes in vascular biology. PMID:17468336

  6. Dietary feeding of Opuntia humifusa inhibits UVB radiation-induced carcinogenesis by reducing inflammation and proliferation in hairless mouse model.

    PubMed

    Lee, Jin-A; Jung, Bock-Gie; Kim, Tae-Hoon; Lee, Su-Gil; Park, Young-Seok; Lee, Bong-Joo

    2013-01-01

    It has been validated that ultraviolet B (UVB) irradiation induced both squamous and basal cell carcinomas, as a tumor initiator and promoter. Opuntia humifusa is a member of the Cactaceae family which has been demonstrated in our previous study to have a chemopreventive effect in 7, 12-dimethylbenz[a]anthracene and 12-O-tetradecanoylphorbol-13-acetate induced skin carcinogenesis models. Therefore, this study was designed to determine the protective effects of O. humifusa against photocarcinogenesis. O. humifusa was administrated to mice as a dietary feeding, following exposure to UVB radiation (180 mJ/cm(2)) twice a week of 30 weeks for skin tumor development in hairless mice. Dietary O. humifusa inhibited UVB-induced epidermal hyperplasia, infiltration of leukocytes, level of myeloperoxidase and the levels of proinflammatory cytokines, tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6), in UVB exposed skin. Also, O. humifusa significantly inhibited both protein and mRNA expression level of cyclooxygenase-2 (COX-2), nitric oxide synthase (iNOS), proliferating cell nuclear antigen (PCNA) and cyclin D1 compared to the non-O. humifusa treated group. Collectively, these results suggest that O. humifusa could inhibit photocarcinogenesis in mouse skin and that protective effect is associated with the inhibition of not only UVB-induced inflammatory responses involving COX-2, iNOS and proinflammatory cytokines, but also the down-regulation of UVB-induced cellular proliferation. PMID:23789636

  7. Growth inhibition of head and neck squamous cell carcinoma cells by sgRNA targeting the cyclin D1 mRNA based on TRUE gene silencing.

    PubMed

    Iizuka, Satoshi; Oridate, Nobuhiko; Nashimoto, Masayuki; Fukuda, Satoshi; Tamura, Masato

    2014-01-01

    Head and neck squamous cell carcinoma (HNSCC) exhibits increased expression of cyclin D1 (CCND1). Previous studies have shown a correlation between poor prognosis of HNSCC and cyclin D1 overexpression. tRNase ZL-utilizing efficacious gene silencing (TRUE gene silencing) is one of the RNA-mediated gene expression control technologies that have therapeutic potential. This technology is based on a unique enzymatic property of mammalian tRNase ZL, which is that it can cleave any target RNA at any desired site by recognizing a pre-tRNA-like complex formed between the target RNA and an artificial small guide RNA (sgRNA). In this study, we designed several sgRNAs targeting human cyclin D1 mRNA to examine growth inhibition of HNSCC cells. Transfection of certain sgRNAs decreased levels of cyclin D1 mRNA and protein in HSC-2 and HSC-3 cells, and also inhibited their proliferation. The combination of these sgRNAs and cisplatin showed more than additive inhibition of cancer cell growth. These findings demonstrate that TRUE gene silencing of cyclin D1 leads to inhibition of the growth of HNSCC cells and suggest that these sgRNAs alone or combined with cisplatin may be a useful new therapy for HNSCCs. PMID:25437003

  8. Imatinib mesylate inhibits platelet derived growth factor stimulated proliferation of rheumatoid synovial fibroblasts

    SciTech Connect

    Sandler, Charlotta; Joutsiniemi, Saima; Lindstedt, Ken A.; Juutilainen, Timo; Kovanen, Petri T.; Eklund, Kari K. . E-mail: kari.eklund@hus.fi

    2006-08-18

    Synovial fibroblast is the key cell type in the growth of the pathological synovial tissue in arthritis. Here, we show that platelet-derived growth factor (PDGF) is a potent mitogen for synovial fibroblasts isolated from patients with rheumatoid arthritis. Inhibition of PDGF-receptor signalling by imatinib mesylate (1 {mu}M) completely abrogated the PDGF-stimulated proliferation and inhibited approximately 70% of serum-stimulated proliferation of synovial fibroblasts. Similar extent of inhibition was observed when PDGF was neutralized with anti-PDGF antibodies, suggesting that imatinib mesylate does not inhibit pathways other than those mediated by PDGF-receptors. No signs of apoptosis were detected in synovial fibroblasts cultured in the presence of imatinib. These results suggest that imatinib mesylate specifically inhibits PDGF-stimulated proliferation of synovial fibroblasts, and that inhibition of PDGF-receptors could represent a feasible target for novel antirheumatic therapies.

  9. Sirt1 AS lncRNA interacts with its mRNA to inhibit muscle formation by attenuating function of miR-34a

    PubMed Central

    Wang, Guo-qiang; Wang, Yu; Xiong, Yan; Chen, Xiao-Chang; Ma, Mei-ling; Cai, Rui; Gao, Yun; Sun, Yun-mei; Yang, Gong-She; Pang, Wei-Jun

    2016-01-01

    Recent studies demonstrate the functions of long non-coding RNAs (lncRNAs) in mediating gene expression at the transcriptional or translational level. Our previous study identified a Sirt1 antisense (AS) lncRNA transcribed from the Sirt1 AS strand. However, its role and regulatory mechanism is still unknown in myogenesis. Here, functional analyses showed that Sirt1 AS lncRNA overexpression promoted myoblast proliferation, but inhibited differentiation. Mechanistically, Sirt1 AS lncRNA was found to activate its sense gene, Sirt1. The luciferase assay provided evidences that Sirt1 AS lncRNA interacted with Sirt1 3′ UTR and rescued Sirt1 transcriptional suppression by competing with miR-34a. In addition, RNA stability assay showed that Sirt1 AS lncRNA prolonged Sirt1 mRNA half-life from 2 to 10 h. Ribonuclease protection assay further indicated that it fully bound to Sirt1 mRNA in the myoblast cytoplasm. Moreover, Sirt1 AS overexpression led to less mouse weight than the control because of less lean mass and greater levels of Sirt1, whereas the fat mass and levels of miR-34a were not altered. Based on the findings, a novel regulatory mechanism was found that Sirt1 AS lncRNA preferably interacted with Sirt1 mRNA forming RNA duplex to promote Sirt1 translation by competing with miR-34a, inhibiting muscle formation. PMID:26902620

  10. MicroRNA-141 inhibits vascular smooth muscle cell proliferation through targeting PAPP-A

    PubMed Central

    Zhang, Yudong; Chen, Bainan; Ming, Liu; Qin, Hongsong; Zheng, Liu; Yue, Zhang; Cheng, Zhixin; Wang, Yannan; Zhang, Dawei; Liu, Chunmei; Bin, Wang; Hao, Qingzhi; Song, Fuchen; Ji, Bo

    2015-01-01

    It is well known that ox-LDL plays key roles in the development of atherosclerosis, partly by inducing vascular smooth muscle cells (VSMCs) proliferation. Recent findings have revealed that microRNAs, a class of small noncoding RNAs, could regulate cell proliferation in many physiological and pathological conditions. However, the role and function of miRNAs on ox-LDL induced VSMC proliferation are not fully elucidated. In this study, we showed that ox-LDL could suppress miR-141 expression and inhibition of miR-141 could promote VSMCs proliferation. Moreover, we found that PAPPA was the direct target gene of miR-141. Overexpression of PAPPA impaired the miR-141-induced inhibition of proliferation in the VSMCs. Taken together; miR-141 may play important roles in ox-LDL-induced abnormal proliferation of the VSMC. PMID:26823756

  11. Knockdown of Long Noncoding RNA GHET1 Inhibits Cell Proliferation and Invasion of Colorectal Cancer.

    PubMed

    Zhou, Jianyu; Li, Xiaorong; Wu, Meirong; Lin, Changwei; Guo, Yihang; Tian, Buning

    2016-01-01

    Emerging evidence has identified the vital role of long noncoding RNAs (lncRNAs) in the development of colorectal cancer. In this study, we aimed to investigate the role of lncRNA gastric carcinoma highly expressed transcript 1 (GHET1) in colorectal cancer. We analyzed the expression of GHET1 in colorectal cancer (CRC) tissues by using ISH. We found that GHET1 expression was significantly increased in the CRC samples compared with adjacent tissues. Furthermore, the cancer tissues had higher GHET1 mRNA levels than their matched adjacent tissues. GHET1 expression was also significantly increased in the CRC cell lines compared with human normal colon epithelial cells. Downregulation of GHET1 mediated by shRNA suppressed the proliferation, cell cycle arrest, migration, and invasion of colorectal cancer cells in vitro. In addition, inhibition of GHET1 reversed the epithelial-mesenchymal transition in colorectal cancer cell lines. Taken together, our results suggest the potential use of GHET1 as a therapeutic target of colorectal cancer. PMID:27131316

  12. HIV-1 Vif binds to APOBEC3G mRNA and inhibits its translation

    PubMed Central

    Mercenne, Gaëlle; Bernacchi, Serena; Richer, Delphine; Bec, Guillaume; Henriet, Simon; Paillart, Jean-Christophe; Marquet, Roland

    2010-01-01

    The HIV-1 viral infectivity factor (Vif) allows productive infection of non-permissive cells (including most natural HIV-1 targets) by counteracting the cellular cytosine deaminases APOBEC-3G (hA3G) and hA3F. The Vif-induced degradation of these restriction factors by the proteasome has been extensively studied, but little is known about the translational repression of hA3G and hA3F by Vif, which has also been proposed to participate in Vif function. Here, we studied Vif binding to hA3G mRNA and its role in translational repression. Filter binding assays and fluorescence titration curves revealed that Vif tightly binds to hA3G mRNA. Vif overall binding affinity was higher for the 3′UTR than for the 5′UTR, even though this region contained at least one high affinity Vif binding site (apparent Kd = 27 ± 6 nM). Several Vif binding sites were identified in 5′ and 3′UTRs using RNase footprinting. In vitro translation evidenced that Vif inhibited hA3G translation by two mechanisms: a main time-independent process requiring the 5′UTR and an additional time-dependent, UTR-independent process. Results using a Vif protein mutated in the multimerization domain suggested that the molecular mechanism of translational control is more complicated than a simple physical blockage of scanning ribosomes. PMID:19910370

  13. HIV-1 Vif binds to APOBEC3G mRNA and inhibits its translation.

    PubMed

    Mercenne, Gaëlle; Bernacchi, Serena; Richer, Delphine; Bec, Guillaume; Henriet, Simon; Paillart, Jean-Christophe; Marquet, Roland

    2010-01-01

    The HIV-1 viral infectivity factor (Vif) allows productive infection of non-permissive cells (including most natural HIV-1 targets) by counteracting the cellular cytosine deaminases APOBEC-3G (hA3G) and hA3F. The Vif-induced degradation of these restriction factors by the proteasome has been extensively studied, but little is known about the translational repression of hA3G and hA3F by Vif, which has also been proposed to participate in Vif function. Here, we studied Vif binding to hA3G mRNA and its role in translational repression. Filter binding assays and fluorescence titration curves revealed that Vif tightly binds to hA3G mRNA. Vif overall binding affinity was higher for the 3'UTR than for the 5'UTR, even though this region contained at least one high affinity Vif binding site (apparent K(d) = 27 +/- 6 nM). Several Vif binding sites were identified in 5' and 3'UTRs using RNase footprinting. In vitro translation evidenced that Vif inhibited hA3G translation by two mechanisms: a main time-independent process requiring the 5'UTR and an additional time-dependent, UTR-independent process. Results using a Vif protein mutated in the multimerization domain suggested that the molecular mechanism of translational control is more complicated than a simple physical blockage of scanning ribosomes. PMID:19910370

  14. MicroRNA-101 inhibits the proliferation and invasion of bladder cancer cells via targeting c-FOS.

    PubMed

    Long, Yongqi; Wu, Zhiping; Yang, Xinhua; Chen, Lei; Han, Zhijun; Zhang, Yulong; Liu, Jinge; Liu, Wenjin; Liu, Xinyi

    2016-09-01

    MicroRNAs (miRs) have important roles in the parthenogenesis of malignancies. While it has been suggested that deregulation of miR‑101 is involved in bladder cancer, the underlying mechanisms have remained largely elusive. The present study aimed to investigate the roles of miR‑101 in the regulation of bladder cancer cell proliferation and invasion. Reverse‑transcription quantitative polymerase chain reaction analysis revealed that the expression of miR‑101 was significantly reduced in the HT‑1376, BIU87, T24 and 5637 several human bladder cancer cell lines compared to that in the SV‑HUC‑1 normal bladder epithelial cell line. Furthermore, a Targetscan search and a luciferase assay were used to identify c‑FOS as a novel target of miR‑101, and western blot analysis indicated that the protein expression of c‑FOS was shown to be negatively regulated by miR‑101 in bladder cancer T24 cells; however, c‑FOS mRNA expression was not affected. In addition, plasmid‑mediated overexpression of miR‑101 and small hairpin RNA‑mediated inhibition of c‑FOS significantly inhibited the proliferation and invasive capacity of T24 cells, as indicated by an MTT and a Transwell assay, respectively. However, plasmid‑mediated overexpression of c‑FOS reversed the inhibitory effects of miR‑101 overexpression on T24‑cell proliferation and invasion. In conclusion, the present study demonstrated that miR‑101 inhibits the proliferation and invasion of bladder cancer cells, at least partly via targeting c‑FOS, suggesting that miR-101/c‑FOS signaling may represent a potential therapeutic target for bladder cancer. PMID:27485165

  15. Predators inhibit brain cell proliferation in natural populations of electric fish, Brachyhypopomus occidentalis.

    PubMed

    Dunlap, Kent D; Tran, Alex; Ragazzi, Michael A; Krahe, Rüdiger; Salazar, Vielka L

    2016-02-10

    Compared with laboratory environments, complex natural environments promote brain cell proliferation and neurogenesis. Predators are one important feature of many natural environments, but, in the laboratory, predatory stimuli tend to inhibit brain cell proliferation. Often, laboratory predatory stimuli also elevate plasma glucocorticoids, which can then reduce brain cell proliferation. However, it is unknown how natural predators affect cell proliferation or whether glucocorticoids mediate the neurogenic response to natural predators. We examined brain cell proliferation in six populations of the electric fish, Brachyhypopomus occidentalis, exposed to three forms of predator stimuli: (i) natural variation in the density of predatory catfish; (ii) tail injury, presumably from predation attempts; and (iii) the acute stress of capture. Populations with higher predation pressure had lower density of proliferating (PCNA+) cells, and fish with injured tails had lower proliferating cell density than those with intact tails. However, plasma cortisol did not vary at the population level according to predation pressure or at the individual level according to tail injury. Capture stress significantly increased cortisol, but only marginally decreased cell proliferation. Thus, it appears that the presence of natural predators inhibits brain cell proliferation, but not via mechanisms that depend on changes in basal cortisol levels. This study is the first demonstration of predator-induced alteration of brain cell proliferation in a free-living vertebrate. PMID:26842566

  16. Ghrelin and obestatin inhibit enucleation-induced adrenocortical proliferation in the rat.

    PubMed

    Rucinski, Marcin; Trejter, Marcin; Ziolkowska, Agnieszka; Tyczewska, Marianna; Malendowicz, Ludwik K

    2010-05-01

    Studies involving the role of ghrelin (GHREL) in regulating the proliferative activity of various cell types have obtained variable results depending primarily on the experimental model applied. It was recently reported that neither GHREL nor obestatin (OBS) affected the proliferative activity of cultured rat adrenocortical cells. In view of the conflicting results, we investigated the effects of GHREL and OBS on the proliferative activity of rat adrenocortical cells in a model of bilateral enucleation-induced adrenocortical regeneration in the rat. Rats were sacrificed 5 or 8 days after surgery. Twenty-four hours before being sacrificed, the appropriate groups were infused with 3 nmol GHREL or OBS/100 g. The mitotic index was assessed using the stachmokinetic method with vincristine. In comparison with intact rats, expression levels of ppGHREL, BAX, JUN-B and JUN-C genes were notably higher in regenerating adrenals, and neither GHREL nor OBS infusion affected these levels. Expression levels of the GHS-R, GPR39v2 and FOS genes were affected neither by adrenal enucleation nor GHREL or OBS infusion. Expression of only two studied genes, GPR39v1 and EGR1, was regulated by OBS. In the regenerating adrenal glands, GPR39v1 and EGR1 mRNA levels were higher than the levels in intact animals. GHREL infusion had no effect while OBS infusion notably stimulated GPR39v1 mRNA levels in the regenerating adrenal gland and evoked an opposite effect on EGR1 mRNA. OBS administration resulted in a potent decrease in the mitotic index of the studied cells, an effect found at both days 5 and 8 of the experiment. GHREL exerted a similar effect only at day 5 of adrenocortical regeneration. Neither GHREL nor OBS had an effect on blood aldosterone concentrations. GHREL infusion lowered plasma corticosterone concentration at day 5 but not 8 of the experiment, while OBS administration was ineffective. Thus, this study is the first to demonstrate that, in vivo, both GHREL and OBS inhibit the

  17. Inhibition of proliferation and induction of apoptosis in soft tissue sarcoma cells by interferon-α and retinoids

    PubMed Central

    Brodowicz, T; Wiltschke, C; Kandioler-Eckersberger, D; Grunt, T W; Rudas, M; Schneider, S M; Hejna, M; Budinsky, A; Zielinski, C C

    1999-01-01

    Uncontrolled proliferation and a defect of apoptosis constitute crucial elements in the development and progression of tumours. Among many other biological response modifiers known to influence these mechanisms, the efficacy of retinoids and interferons in the treatment of various malignant entities is currently matter of discussion. In the present study, we have investigated the effects of 9-cis-retinoic acid (9cRA), 13-cis-retinoic acid (13cRA), all-trans-retinoic acid (tRA) and interferon-α on proliferation and apoptosis of human soft tissue sarcoma (STS) cell lines HTB-82 (rhabdomyosarcoma), HTB-91 (fibrosarcoma), HTB-92 (liposarcoma), HTB-93 (synovial sarcoma) and HTB-94 (chondrosarcoma) in relation to p53 genotype as well as p53 expression. HTB-91, HTB-92 and HTB-94 STS cells exhibited mutant p53, whereas wild-type p53 was found in HTB-93 STS cells, and a normal p53 status in HTB-82 STS cells, carrying a silent point mutation only. Interferon-α, irrespective of p53 status, inhibited the proliferation of all five cell lines dose- and time-dependently. Similarly, 9cRA, 13cRA and tRA decreased the proliferation of HTB-82 and HTB-93 STS cells, whereas the proliferation of p53-mutated HTB-91, HTB-92 and HTB-94 STS cells remained unchanged. Furthermore, only 9cRA and tRA were capable of inducing apoptosis in HTB-82 and HTB-93 STS cells, whereas HTB-91, HTB-92 and HTB-94 STS cells did not undergo apoptosis under the influence of 9cRA or tRA. Retinoic acid receptor (RAR)-α and RAR-β mRNA were not detectable by Northern blot analysis in the five STS cell lines, whereas mRNA for the universal retinoic acid receptor, RAR-γ, was expressed in all STS cell lines indicating that retinoid resistance was not associated with a lack of RAR expression. Apoptosis was not induced by interferon-α or 13cRA in any of the five STS cell lines tested. Our results indicate that within the panel of tested STS cell lines, inhibition of proliferation and induction of apoptosis result

  18. [Inhibition of proliferation of H5N1 subtype AIV in CEF by chemosynthetic siRNA].

    PubMed

    Li, Ru-Shu; Yu, Dan; Luo, Bao-Zheng; Bo, Qing-Ru; Xu, Hai-Nie; Sha, Cai-Hua; Liao, Xiu-Yun

    2013-06-01

    In order to study the proliferation inhibition effect of H5N1 subtype avian influenza virus (AIV) with small interfere RNA (siRNA), a total of 4 siRNAs were designed in accordance with the NP and PA genes of H5N1 subtype AIV, the siRNAs were then transfected to chicken embryo fibroblast(CEF), CEF was infected with H5N1 subtype AIV after 6 hrs. Virus titer of cell supernatant was tested at 16-56hrs post infection, and pathological changes of the cells was observed; mRNA levels of NP, PA, HA and p13-actin gene were tested at 36hrs post infection. The results showed that these 4 siRNAs could inhibit the prolif-eration of H5N1 subtype AIV in CEF in varying degrees, and one siRNA targeting PA was best per-formed. The experimental results also showed that the inhibition effect was decreased with the time prolonged. This research provides a basis for further studying RNAi on AIV prevention and control. PMID:23895002

  19. Oxymatrine Downregulates HPV16E7 Expression and Inhibits Cell Proliferation in Laryngeal Squamous Cell Carcinoma Hep-2 Cells In Vitro

    PubMed Central

    Ying, Xin-Jiang; Jin, Bin; Chen, Xin-Wei; Xie, Jin; Xu, Hong-Ming; Dong, Pin

    2015-01-01

    Objective. To investigate the possible mechanisms of oxymatrine's role in anti laryngeal squamous cell carcinoma. Methods. We examined the effects of oxymatrine on the proliferation, cell cycle phase distribution, apoptosis, and the protein and mRNA expression levels of HPV16E7 gene in laryngeal carcinoma Hep-2 cells in vitro. The HPV16E7 siRNA inhibition was also done to confirm the effect of downregulating HPV16E7 on the proliferation in Hep-2 cells. Results. Oxymatrine significantly inhibited the growth and proliferation of Hep-2 cells in a dose-dependence and time-dependence manner. Oxymatrine blocked Hep-2 cells in G0/G1 phase, resulting in an obvious accumulation of G0/G1 phase cells while decreasing S phase cells. Oxymatrine induced apoptosis of Hep-2 cells, whose apoptotic rate amounted to about 42% after treatment with 7 mg/mL oxymatrine for 72 h. Oxymatrine also downregulated the expression of HPV16E7 gene, as determined by the western blotting and reverse transcription-polymerase chain reaction analysis. Knockdown of HPV16E7 effectively inhibited the proliferation of Hep-2 cells. Conclusions. Oxymatrine inhibits the proliferation and induces apoptosis of laryngeal carcinoma Hep-2 cells, which might be mediated by a significant cell cycle arrest in G0/G1 phase and downregulation of HPV16E7 gene. Oxymatrine is considered to be a likely preventive and curative candidate for laryngeal cancer. PMID:25811021

  20. NS-398, a selective COX-2 inhibitor, inhibits proliferation of IL-1{beta}-stimulated vascular smooth muscle cells by induction of {eta}{omicron}-1

    SciTech Connect

    Choi, Hyoung Chul; Kim, Hee Sun; Lee, Kwang Youn; Chang, Ki Churl Kang, Young Jin

    2008-11-28

    We investigated whether NS-398, a selective inhibitor of COX-2, induces HO-1 in IL-1{beta}-stimulated vascular smooth muscle cells (VSMC). NS-398 reduced the production of PGE{sub 2} without modulation of expression of COX-2 in IL-1{beta}-stimulated VSMC. NS-398 increased HO-1 mRNA and protein in a dose-dependent manner, but inhibited proliferation of IL-1{beta}-stimulated VSMC. Furthermore, SnPPIX, a HO-1 inhibitor, reversed the effects of NS-398 on PGE{sub 2} production, suggesting that COX-2 activity can be affected by HO-1. Hemin, a HO-1 inducer, also reduced the production of PGE{sub 2} and proliferation of IL-1{beta}-stimulated VSMC. CORM-2, a CO-releasing molecule, but not bilirubin inhibited proliferation of IL-1{beta}-stimulated VSMC. NS-398 inhibited proliferation of IL-1{beta}-stimulated VSMC in a HbO{sub 2}-sensitive manner. In conclusion, NS-398 inhibits proliferation of IL-1{beta}-stimulated VSMC by HO-1-derived CO. Thus, NS-398 may facilitate the healing process of vessels in vascular inflammatory disorders such as atherosclerosis.

  1. EDNRA variants associate with smooth muscle mRNA levels, cell proliferation rates, and cystic fibrosis pulmonary disease severity

    PubMed Central

    Darrah, Rebecca; McKone, Edward; O'Connor, Clare; Rodgers, Christine; Genatossio, Alan; McNamara, Sharon; Gibson, Ronald; Stuart Elborn, J.; Ennis, Madeleine; Gallagher, Charles G.; Kalsheker, Noor; Aitken, Moira; Wiese, Dawn; Dunn, John; Smith, Paul; Pace, Rhonda; Londono, Douglas; Goddard, Katrina A. B.; Knowles, Michael R.

    2010-01-01

    Airway inflammation and pulmonary disease are heterogeneous phenotypes in cystic fibrosis (CF) patients, even among patients with the same cystic fibrosis transmembrane conductance regulator (CFTR) genotype. Endothelin, a proinflammatory peptide and smooth muscle agonist, is increased in CF airways, potentially contributing to the pulmonary phenotype. Four cohorts of CF patients were screened for variants in endothelin pathway genes to determine whether any of these variants associated with pulmonary function. An initial cohort of 808 CF patients homozygous for the common CF mutation, ΔF508, showed significant association for polymorphisms in the endothelin receptor A gene, EDNRA (P = 0.04), but not in the related endothelin genes (EDN1, EDN2, EDN3, or EDNRB) or NOS1, NOS2A, or NOS3. Variants within EDNRA were examined in three additional cohorts of CF patients, 238 patients from Seattle, WA, 303 from Ireland and the U.K., and 228 from Cleveland, OH, for a total of 1,577 CF patients. The three additional groups each demonstrated a significant association between EDNRA 3′-untranslated region (UTR) variant rs5335 and pulmonary function (P = 0.002). At the molecular level, single nucleotide primer extension assays suggest that the effect of the variants is quantitative. EDNRA mRNA levels from cultured primary tracheal smooth muscle cells are greater for the allele that appears to be deleterious to lung function than for the protective allele, suggesting a mechanism by which increased receptor function is harmful to the CF airway. Finally, cell proliferation studies using human airway smooth muscle cells demonstrated that cells homozygous for the deleterious allele proliferate at a faster rate than those homozygous for the protective allele. PMID:20028935

  2. PPARγ Inhibits VSMC Proliferation and Migration via Attenuating Oxidative Stress through Upregulating UCP2

    PubMed Central

    Zhou, Yi; Zhang, Ming-Jie; Li, Bing-Hu; Chen, Lei; Pi, Yan; Yin, Yan-Wei; Long, Chun-Yan; Wang, Xu; Sun, Meng-Jiao; Chen, Xue; Gao, Chang-Yue; Li, Jing-Cheng; Zhang, Li-Li

    2016-01-01

    Increasing evidence showed that abnormal proliferation and migration of vascular smooth muscle cells (VSMCs) are common event in the pathophysiology of many vascular diseases, including atherosclerosis and restenosis after angioplasty. Among the underlying mechanisms, oxidative stress is one of the principal contributors to the proliferation and migration of VSMCs. Oxidative stress occurs as a result of persistent production of reactive oxygen species (ROS). Recently, the protective effects of peroxisome proliferator-activated receptor γ (PPARγ) against oxidative stress/ROS in other cell types provide new insights to inhibit the suggests that PPARγ may regulate VSMCs function. However, it remains unclear whether activation of PPARγ can attenuate oxidative stress and further inhibit VSMC proliferation and migration. In this study, we therefore investigated the effect of PPARγ on inhibiting VSMC oxidative stress and the capability of proliferation and migration, and the potential role of mitochondrial uncoupling protein 2 (UCP2) in oxidative stress. It was found that platelet derived growth factor-BB (PDGF-BB) induced VSMC proliferation and migration as well as ROS production; PPARγ inhibited PDGF-BB-induced VSMC proliferation, migration and oxidative stress; PPARγ activation upregulated UCP2 expression in VSMCs; PPARγ inhibited PDGF-BB-induced ROS in VSMCs by upregulating UCP2 expression; PPARγ ameliorated injury-induced oxidative stress and intimal hyperplasia (IH) in UCP2-dependent manner. In conclusion, our study provides evidence that activation of PPARγ can attenuate ROS and VSMC proliferation and migration by upregulating UCP2 expression, and thus inhibit IH following carotid injury. These findings suggest PPARγ may represent a prospective target for the prevention and treatment of IH-associated vascular diseases. PMID:27144886

  3. Gedunin, a novel natural substance, inhibits ovarian cancer cell proliferation.

    PubMed

    Kamath, Siddharth G; Chen, Ning; Xiong, Yin; Wenham, Robert; Apte, Sachin; Humphrey, Marcia; Cragun, Janiel; Lancaster, Johnathan M

    2009-12-01

    The discovery of more active therapeutic compounds is essential if the outcome for patients with advanced-stage epithelial ovarian cancer is to be improved. Gedunin, an extract of the neem tree, has been used as a natural remedy for centuries in Asia. Recently, gedunin has been shown to have potential in vitro antineoplastic properties; however, its effect on ovarian cancer cells is unknown. We evaluated the in vitro effect of gedunin on SKOV3, OVCAR4, and OVCAR8 ovarian cancer cell lines proliferation, alone and in the presence of cisplatin. Furthermore, we analyzed in vitro gedunin sensitivity data, integrated with genome-wide expression data from 54 cancer cell lines in an effort to identify genes and molecular pathways that underlie the mechanism of gedunin action. In vitro treatment of ovarian cancer cell lines with gedunin alone produced up to an 80% decrease in cell proliferation (P < 0.01) and, combining gedunin with cisplatin, demonstrated up to a 47% (P < 0.01) decrease in cell proliferation compared with cisplatin treatment alone. Bioinformatic analysis of integrated gedunin sensitivity and gene expression data identified 52 genes to be associated with gedunin sensitivity. These genes are involved in molecular functions related to cell cycle control, carcinogenesis, lipid metabolism, and molecular transportation. We conclude that gedunin has in vitro activity against ovarian cancer cells and, further, may enhance the antiproliferative effect of cisplatin. The molecular determinants of in vitro gedunin response are complex and may include modulation of cell survival and apoptosis pathways. PMID:19955938

  4. Telmisartan Induced Inhibition of Vascular Cell Proliferation beyond Angiotensin Receptor Blockade and PPARγ Activation

    PubMed Central

    Yamamoto, Koichi; Ohishi, Mitsuru; Ho, Christopher; Kurtz, Theodore W; Rakugi, Hiromi

    2010-01-01

    We investigated the ability of ARBs with PPARγ agonist activity (telmisartan and irbesartan), and ARBs devoid of PPARγ agonist activity (eprosartan and valsartan), to inhibit vascular cell proliferation studied in the absence of angiotensin II stimulation. Telmisartan and to a lesser extent irbesartan, inhibited proliferation of human aortic vascular smooth muscle cells in a dose dependent fashion whereas eprosartan and valsartan did not. To investigate the role of PPARγ in the antiproliferative effects of telmisartan, we studied genetically engineered NIH3T3 cells that express PPARγ. Pioglitazone inhibited proliferation of NIH3T3 cells expressing PPARγ, but had little effect on control NIH3T3 cells that lack PPARγ. In contrast, telmisartan inhibited proliferation equally in NIH3T3 with and without PPARγ. Valsartan failed to inhibit proliferation of either cell line. In addition, telmisartan inhibited proliferation equally in aortic smooth muscle cells derived from mice with targeted knockout of PPARγ in smooth muscle and from control mice whereas valsartan had no effect on cell proliferation. Telmisartan but not valsartan, reduced phosphorylation of AKT but not ERK otherwise induced by exposure to serum of either quiescent human smooth muscle cells, quiescent mice smooth muscle cells lacking PPARγ or quiescent CHO-K1 cells lacking AT1 receptor. In summary, the antiproliferative effect of telmisartan in the absence of exogenously supplemented angiotensin II involve more than just AT1 receptor blockade and do not require activation of PPARγ. It might be postulated that inhibition of AKT activation is a mechanism mediating the antiproliferative effects of telmisartan including in cells lacking AT1 receptors or PPARγ. PMID:19822796

  5. ETOH inhibits embryonic neural stem/precursor cell proliferation via PLD signaling

    SciTech Connect

    Fujita, Yuko; Hiroyama, Masami; Sanbe, Atsushi Yamauchi, Junji; Murase, Shoko; Tanoue, Akito

    2008-05-23

    While a mother's excessive alcohol consumption during pregnancy is known to have adverse effects on fetal neural development, little is known about the underlying mechanism of these effects. In order to investigate these mechanisms, we investigated the toxic effect of ethanol (ETOH) on neural stem/precursor cell (NSC) proliferation. In cultures of NSCs, phospholipase D (PLD) is activated following stimulation with epidermal growth factor (EGF) and fibroblast growth factor 2 (FGF2). Exposure of NSCs to ETOH suppresses cell proliferation, while it has no effect on cell death. Phosphatidic acid (PA), which is a signaling messenger produced by PLD, reverses ETOH inhibition of NSC proliferation. Blocking the PLD signal by 1-butanol suppresses the proliferation. ETOH-induced suppression of NSC proliferation and the protective effect of PA for ETOH-induced suppression are mediated through extracellular signal-regulated kinase signaling. These results indicate that exposure to ETOH impairs NSC proliferation by altering the PLD signaling pathway.

  6. Influenza virus NS1 protein inhibits pre-mRNA splicing and blocks mRNA nucleocytoplasmic transport.

    PubMed Central

    Fortes, P; Beloso, A; Ortín, J

    1994-01-01

    The influenza virus RNA segment 8 encodes two proteins, NS1 and NS2, by differential splicing. The collinear transcript acts as mRNA for NS1 protein, while the spliced mRNA encodes NS2 protein. The splicing of NS1 mRNA was studied in cells transfected with a recombinant plasmid that has the cDNA of RNA segment 8 cloned under the SV40 late promoter and polyadenylation signals. As described for influenza virus-infected cells, NS1 mRNA was poorly spliced to yield NS2 mRNA. However, inactivation of the NS1 gene, but not the NS2 gene, led to a substantial increase in the splicing efficiency, as shown by the relative accumulations of NS1 and NS2 mRNAs. This effect was not specific for NS1 mRNA, since the splicing of the endogenous SV40 early transcript was altered in such a way that t-Ag mRNA was almost eliminated. These changes in the splicing pattern coincided with a strong inhibition of the mRNA nucleocytoplasmic transport. Both NS1 and NS2 mRNAs were retained in the nucleus of cells expressing NS1 protein, but no effect was observed when only NS2 protein was expressed. Furthermore, other mRNAs tested, such as T-Ag mRNA and the non-spliceable nucleoprotein transcript, were also retained in the nucleus upon expression of NS1 protein, suggesting that it induced a generalized block of mRNA export from the nucleus. Images PMID:8313914

  7. Cucurbitacin B inhibits proliferation and induces apoptosis via STAT3 pathway inhibition in A549 lung cancer cells

    PubMed Central

    ZHANG, MENG; BIAN, ZHI-GANG; ZHANG, YI; WANG, JIA-HE; KAN, LIANG; WANG, XIN; NIU, HUI-YAN; HE, PING

    2014-01-01

    Natural products are a great source of cancer chemotherapeutic agents. The present study was conducted to investigate whether cucurbitacin B (CuB), one of the most potent and widely used cucurbitacins, inhibits proliferation and induces apoptosis in the A549 lung cancer cell line. Furthermore, CuB induced apoptosis of A549 cells in a concentration-dependent manner, as determined by fluorescence microscopy, flow cytometry and transmission electron microscopy. The present study also demonstrated that CuB dose-dependently inhibited lung cancer cell proliferation, with cell cycle inhibition and cyclin B1 downregulation. Apoptosis induced by CuB was shown to be associated with cytochrome c release, B-cell lymphoma 2 downregulation and signal transducer and activator of transcription 3 pathway inhibition. CuB may prove to be a useful approach for the chemotherapy of lung cancer. PMID:25242136

  8. Cucurbitacin B inhibits proliferation and induces apoptosis via STAT3 pathway inhibition in A549 lung cancer cells.

    PubMed

    Zhang, Meng; Bian, Zhi-Gang; Zhang, Yi; Wang, Jia-He; Kan, Liang; Wang, Xin; Niu, Hui-Yan; He, Ping

    2014-12-01

    Natural products are a great source of cancer chemotherapeutic agents. The present study was conducted to investigate whether cucurbitacin B (CuB), one of the most potent and widely used cucurbitacins, inhibits proliferation and induces apoptosis in the A549 lung cancer cell line. Furthermore, CuB induced apoptosis of A549 cells in a -concentration-dependent manner, as determined by fluorescence microscopy, flow cytometry and transmission electron microscopy. The present study also demonstrated that CuB dose-dependently inhibited lung cancer cell proliferation, with cell cycle inhibition and cyclin B1 downregulation. Apoptosis induced by CuB was shown to be associated with cytochrome c release, B-cell lymphoma 2 downregulation and signal transducer and activator of transcription 3 pathway inhibition. CuB may prove to be a useful approach for the chemotherapy of lung cancer. PMID:25242136

  9. A knock-in mouse model reveals roles for nuclear Apc in cell proliferation, Wnt signal inhibition and tumor suppression.

    PubMed

    Zeineldin, M; Cunningham, J; McGuinness, W; Alltizer, P; Cowley, B; Blanchat, B; Xu, W; Pinson, D; Neufeld, K L

    2012-05-10

    Mutation of the tumor suppressor adenomatous polyposis coli (APC) is considered an initiating step in the genesis of the vast majority of colorectal cancers. APC inhibits the Wnt-signaling pathway by targeting the proto-oncogene β-catenin for destruction by cytoplasmic proteasomes. In the presence of a Wnt signal, or in the absence of functional APC, β-catenin can serve as a transcription cofactor for genes required for cell proliferation such as cyclin-D1 and c-Myc. In cultured cells, APC shuttles between the nucleus and the cytoplasm, with nuclear APC implicated in the inhibition of Wnt target gene expression. Adopting a genetic approach to evaluate the functions of nuclear APC in the context of a whole organism, we generated a mouse model with mutations that inactivate the nuclear localization signals (NLSs) of Apc (Apc(mNLS)). Apc(mNLS/mNLS) mice are viable and fractionation of mouse embryonic fibroblasts (MEFs) isolated from these mice revealed a significant reduction in nuclear Apc as compared with Apc(+/+) MEFs. The levels of Apc and β-catenin protein were not significantly altered in small intestinal epithelia from Apc(mNLS/mNLS) mice. Compared with Apc(+/+) mice, Apc(mNLS/mNLS) mice showed increased proliferation in epithelial cells from the jejunum, ileum and colon. These same tissues from Apc(mNLS/mNLS) mice showed more mRNA from three genes upregulated in response to canonical Wnt signal, c-Myc, axin-2 and cyclin-D1, and less mRNA from Hath-1, which is downregulated in response to Wnt. These observations suggest a role for nuclear Apc in the inhibition of canonical Wnt signaling and the control of epithelial proliferation in intestinal tissue. Furthermore, we found Apc(Min/+) mice, which harbor a mutation that truncates Apc, to have an increased polyp size and multiplicity if they also carry the Apc(mNLS) allele. Taken together, this analysis of the novel Apc(mNLS) mouse model supports a role for nuclear Apc in the control of Wnt target genes

  10. Mesenchymal stem cells inhibit lymphocyte proliferation by mitogens and alloantigens by different mechanisms

    SciTech Connect

    Rasmusson, Ida . E-mail: Ida.Rasmusson@labmed.ki.se; Ringden, Olle; Sundberg, Berit; Le Blanc, Katarina

    2005-04-15

    Human mesenchymal stem cells (MSCs) have immuno-modulatory properties. They inhibit T-cell proliferation to mitogens and alloantigens in vitro and prolong skin graft survival in vivo. We found that MSCs inhibited the proliferation of peripheral blood lymphocytes (PBLs) to phorbol myristate acetate (PMA), suggesting that MSCs exert an inhibitory effect downstream of the receptor level. We analyzed cytokine profiles of PBLs co-cultured with MSCs. MSCs increased interleukin (IL)-2 and soluble IL-2 receptor in mixed lymphocyte cultures (MLCs), while IL-2 and IL-2R decreased in phytohemagglutinin (PHA)-stimulated PBL cultures. MSCs inhibited IL-2 induced proliferation, without absorbing IL-2. IL-10 levels increased in MLCs co-cultured with 10% MSCs, while the levels were not affected in PHA cultures. In MLCs inhibited by MSCs, antibodies against IL-10 further suppressed proliferation but had no effect in PHA cultures. Addition of indomethacin, an inhibitor of prostaglandin-synthesis, restored part of the inhibition by MSCs in PHA cultures. However, indomethacin did not affect MSC-induced inhibition in MLCs. To conclude, our data indicate that MSC-induced suppression is a complex mechanism affecting IL-2 and IL-10 signaling and may function differently, depending on T-cell stimuli. Prostaglandins are important in the inhibition by MSCs when the T cells were activated by PHA, but not alloantigens.

  11. Inhibition of tumor cell proliferation and motility by fibroblasts is both contact and soluble factor dependent

    PubMed Central

    Alkasalias, Twana; Flaberg, Emilie; Kashuba, Vladimir; Alexeyenko, Andrey; Pavlova, Tatiana; Savchenko, Andrii; Szekely, Laszlo; Klein, George; Guven, Hayrettin

    2014-01-01

    Normal human and murine fibroblasts can inhibit proliferation of tumor cells when cocultured in vitro. The inhibitory capacity varies depending on the donor and the site of origin of the fibroblast. We showed previously that effective inhibition requires formation of a morphologically intact fibroblast monolayer before seeding of the tumor cells. Here we show that inhibition is extended to motility of tumor cells and we dissect the factors responsible for these inhibitory functions. We find that inhibition is due to two different sets of molecules: (i) the extracellular matrix (ECM) and other surface proteins of the fibroblasts, which are responsible for contact-dependent inhibition of tumor cell proliferation; and (ii) soluble factors secreted by fibroblasts when confronted with tumor cells (confronted conditioned media, CCM) contribute to inhibition of tumor cell proliferation and motility. However, conditioned media (CM) obtained from fibroblasts alone (nonconfronted conditioned media, NCM) did not inhibit tumor cell proliferation and motility. In addition, quantitative PCR (Q-PCR) data show up-regulation of proinflammatory genes. Moreover, comparison of CCM and NCM with an antibody array for 507 different soluble human proteins revealed differential expression of growth differentiation factor 15, dickkopf-related protein 1, endothelial-monocyte-activating polypeptide II, ectodysplasin A2, Galectin-3, chemokine (C-X-C motif) ligand 2, Nidogen1, urokinase, and matrix metalloproteinase 3. PMID:25404301

  12. The antiviral drug ganciclovir does not inhibit microglial proliferation and activation

    PubMed Central

    Skripuletz, Thomas; Salinas Tejedor, Laura; Prajeeth, Chittappen K.; Hansmann, Florian; Chhatbar, Chintan; Kucman, Valeria; Zhang, Ning; Raddatz, Barbara B.; Detje, Claudia N.; Sühs, Kurt-Wolfram; Pul, Refik; Gudi, Viktoria; Kalinke, Ulrich; Baumgärtner, Wolfgang; Stangel, Martin

    2015-01-01

    Ganciclovir is effective in the treatment of human infections with viruses of the Herpesviridae family. Beside antiviral properties, recently ganciclovir was described to inhibit microglial proliferation and disease severity of experimental autoimmune encephalomyelitis, an inflammatory model of multiple sclerosis. Microglial activation and proliferation are main characteristics of neuroinflammatory CNS diseases and inhibition of microglial functions might be beneficial in autoimmune diseases, or detrimental in infectious diseases. The objective of this study was to determine potential inhibitory effects of ganciclovir in three different murine animal models of CNS neuroinflammation in which microglia play an important role: Theiler´s murine encephalomyelitis, the cuprizone model of de- and remyelination, and the vesicular stomatitis virus encephalitis model. In addition, in vitro experiments with microglial cultures were performed to test the hypothesis that ganciclovir inhibits microglial proliferation. In all three animal models, neither microglial proliferation or recruitment nor disease activity was changed by ganciclovir. In vitro experiments confirmed that microglial proliferation was not affected by ganciclovir. In conclusion, our results show that the antiviral drug ganciclovir does not inhibit microglial activation and proliferation in the murine CNS. PMID:26447351

  13. The antiviral drug ganciclovir does not inhibit microglial proliferation and activation.

    PubMed

    Skripuletz, Thomas; Salinas Tejedor, Laura; Prajeeth, Chittappen K; Hansmann, Florian; Chhatbar, Chintan; Kucman, Valeria; Zhang, Ning; Raddatz, Barbara B; Detje, Claudia N; Sühs, Kurt-Wolfram; Pul, Refik; Gudi, Viktoria; Kalinke, Ulrich; Baumgärtner, Wolfgang; Stangel, Martin

    2015-01-01

    Ganciclovir is effective in the treatment of human infections with viruses of the Herpesviridae family. Beside antiviral properties, recently ganciclovir was described to inhibit microglial proliferation and disease severity of experimental autoimmune encephalomyelitis, an inflammatory model of multiple sclerosis. Microglial activation and proliferation are main characteristics of neuroinflammatory CNS diseases and inhibition of microglial functions might be beneficial in autoimmune diseases, or detrimental in infectious diseases. The objective of this study was to determine potential inhibitory effects of ganciclovir in three different murine animal models of CNS neuroinflammation in which microglia play an important role: Theiler´s murine encephalomyelitis, the cuprizone model of de- and remyelination, and the vesicular stomatitis virus encephalitis model. In addition, in vitro experiments with microglial cultures were performed to test the hypothesis that ganciclovir inhibits microglial proliferation. In all three animal models, neither microglial proliferation or recruitment nor disease activity was changed by ganciclovir. In vitro experiments confirmed that microglial proliferation was not affected by ganciclovir. In conclusion, our results show that the antiviral drug ganciclovir does not inhibit microglial activation and proliferation in the murine CNS. PMID:26447351

  14. Nifedipine inhibits advanced glycation end products (AGEs) and their receptor (RAGE) interaction-mediated proximal tubular cell injury via peroxisome proliferator-activated receptor-gamma activation

    SciTech Connect

    Matsui, Takanori; Yamagishi, Sho-ichi; Takeuchi, Masayoshi; Ueda, Seiji; Fukami, Kei; Okuda, Seiya

    2010-07-23

    Research highlights: {yields} Nifedipine inhibited the AGE-induced up-regulation of RAGE mRNA levels in tubular cells, which was prevented by GW9662, an inhibitor of peroxisome proliferator-activated receptor-{gamma}. {yields} GW9662 treatment alone increased RAGE mRNA levels in tubular cells. {yields} Nifedipine inhibited the AGE-induced reactive oxygen species generation, NF-{kappa}B activation and increases in intercellular adhesion molecule-1 and transforming growth factor-{beta} gene expression in tubular cells, all of which were blocked by GW9662. -- Abstract: There is a growing body of evidence that advanced glycation end products (AGEs) and their receptor (RAGE) interaction evokes oxidative stress generation and subsequently elicits inflammatory and fibrogenic reactions, thereby contributing to the development and progression of diabetic nephropathy. We have previously found that nifedipine, a calcium-channel blocker (CCB), inhibits the AGE-induced mesangial cell damage in vitro. However, effects of nifedipine on proximal tubular cell injury remain unknown. We examined here whether and how nifedipine blocked the AGE-induced tubular cell damage. Nifedipine, but not amlodipine, a control CCB, inhibited the AGE-induced up-regulation of RAGE mRNA levels in tubular cells, which was prevented by the simultaneous treatment of GW9662, an inhibitor of peroxisome proliferator-activated receptor-{gamma} (PPAR{gamma}). GW9662 treatment alone was found to increase RAGE mRNA levels in tubular cells. Further, nifedipine inhibited the AGE-induced reactive oxygen species generation, NF-{kappa}B activation and increases in intercellular adhesion molecule-1 and transforming growth factor-beta gene expression in tubular cells, all of which were blocked by GW9662. Our present study provides a unique beneficial aspect of nifedipine on diabetic nephropathy; it could work as an anti-oxidative and anti-inflammatory agent against AGEs in tubular cells by suppressing RAGE expression

  15. 5-Azacytidine suppresses the proliferation of pancreatic cancer cells by inhibiting the Wnt/β-catenin signaling pathway.

    PubMed

    Zhang, H; Zhou, W C; Li, X; Meng, W B; Zhang, L; Zhu, X L; Zhu, K X; Bai, Z T; Yan, J; Liu, T; Xu, X C; Li, Y M

    2014-01-01

    5-Azacytidine has been shown to be an effective anti-pancreatic cancer drug, but the mechanism remains unknown. In the current study, we explored the effect of 5-azacytidine on abnormal activation of the Wnt-β-catenin signaling pathway in pancreatic cancer cells. The human pancreatic cancer cell line Bxpc-3 was treated with different concentrations of 5-azacytidine for various times. The proliferation and early apoptosis of the cells were evaluated using the CCK8 method and flow cytometry, respectively. mRNA and protein expression of β-catenin, c-myc, and cyclinD1 were detected using real-time fluorescent quantitative polymerase chain reaction and Western blot analysis, respectively. The proliferation of Bxpc-3 cells was suppressed by 5-azacytidine. The early apoptosis of the cells was significantly enhanced over time and with increasing drug concentrations. The expression of β-catenin, c-myc, and cyclinD1 were down-regulated, showing significant differences between different concentrations and treatment times (P < 0.05). 5-Azacytidine suppressed the proliferation of pancreatic cancer cells by inhibiting the Wnt/β-catenin signaling pathway, particularly the expression of β-catenin, c-myc, and cyclinD1. This study may provide a new potential strategy for diagnosing and treating pancreatic cancer. PMID:25061731

  16. Jia-Shen decoction-medicated serum inhibits angiotensin-II induced cardiac fibroblast proliferation via the TGF-β1/Smad signaling pathway

    PubMed Central

    Cui, Lin; Wang, Youping; Yu, Rui; Li, Bin; Xie, Shiyang; Gao, Yuan; Wang, Xiaoxiao; Zhu, Mingjun

    2016-01-01

    Jia-Shen decoction (JSD) is a traditional Chinese medicine, which is used widely to treat chronic heart failure. However, the underlying mechanism remains to be elucidated. The present study aimed to investigate the mechanism underlying the effects of JSD on cardiac fibroblast (CF) proliferation and differentiation. The CFs were obtained from the hearts of neonatal (1-3-day old) Sprague-Dawley rats and treated with JSD-medicated serum (JSDS) with or without angiotensin II (Ang II). Cell proliferation was assessed using Cell Counting Kit-8 reagent. In addition, the mRNA expression levels of transforming growth factor-β1 (TGF-β1) and phosphorylated small mothers against decapentaplegic (p-Smad)2/3 and their protein expression levels were analyzed. CF proliferation was significantly increased in the Ang II-treated group, compared with the control group (P<0.05). The expression levels of collagen, α-smooth muscle actin, TGF-β1 and p-Smad2/3 were also increased in the Ang II-treated group (P<0.05). Following JSDS treatment, the increased levels of collagen and cell proliferation were inhibited, and the increased expression levels of p-Smad2 and p-Smad3 were also inhibited (P<0.05). These data suggested that JSDS may inhibit CF proliferation via attenuating the TGF-β1/Smad signaling pathway. PMID:27315199

  17. Alternol inhibits the proliferation and induces the differentiation of the mouse melanoma B16F0 cell line.

    PubMed

    Wang, Caixia; Xu, Wenjuan; Hao, Wenjin; Wang, Bingsheng; Zheng, Qiusheng

    2016-08-01

    High malignant potential and low susceptibility to treatment are characteristics of malignant melanoma. Alternol, a novel compound purified from microbial fermentation products obtained from the bark of the yew tree, exhibits a variety of antitumor activities. Based on these findings, the aim of the present study was to extend the knowledge on the antineoplastic effect of alternol in the mouse melanoma B16F0 cell line. Alternol significantly inhibited the proliferation and colony formation of B16F0 cells in a dose-dependent manner as detected by MTT and soft agar colony formation assays. NaOH alkaline lysis and oxidation of Dopa indicated that alternol enhanced the melanin content and tyrosinase activity of the B16F0 cells and results also showed a dose‑response relationship. Morphologic changes accompanied by extended dendrites were discovered in the B16F0 cells after treatment with alternol. Furthermore, the mRNA levels of tyrosinase, Trp1 and Trp2 were increased by alternol. Our results confirmed that alternol possesses marked antineoplastic properties against melanoma cells, indicating that this microbial fermentation product is a promising agent for the differentiation therapy of cancer. The inhibition of cell proliferation and colony formation by alternol was associated with both cytotoxicity and induction of differentiation. PMID:27278753

  18. Substituted oxines inhibit endothelial cell proliferation and angiogenesis†

    PubMed Central

    Bhat, Shridhar; Shim, Joong Sup; Zhang, Feiran; Chong, Curtis Robert; Liu, Jun O.

    2013-01-01

    Two substituted oxines, nitroxoline (5) and 5-chloroquinolin-8-yl phenylcarbamate (22), were identified as hits in a high-throughput screen aimed at finding new anti-angiogenic agents. In a previous study, we have elucidated the molecular mechanism of antiproliferative activity of nitroxoline in endothelial cells, which comprises of a dual inhibition of type 2 human methionine aminopeptidase (MetAP2) and sirtuin 1 (SIRT1). Structure–activity relationship study (SAR) of nitroxoline offered many surprises where minor modifications yielded oxine derivatives with increased potency against human umbilical vein endothelial cells (HUVEC), but with entirely different as yet unknown mechanisms. For example, 5-nitrosoquinolin-8-ol (33) inhibited HUVEC growth with sub-micromolar IC50, but did not affect MetAP2 or MetAP1, and it only showed weak inhibition against SIRT1. Other sub-micromolar inhibitors were derivatives of 5-aminoquinolin-8-ol (34) and 8-sulfonamidoquinoline (32). A sulfamate derivative of nitroxoline (48) was found to be more potent than nitroxoline with the retention of activities against MetAP2 and SIRT1. The bioactivity of the second hit, micromolar HUVEC and MetAP2 inhibitor carbamate 22 was improved further with an SAR study culminating in carbamate 24 which is a nanomolar inhibitor of HUVEC and MetAP2. PMID:22391578

  19. miR-98 targets ITGB3 to inhibit proliferation, migration, and invasion of non-small-cell lung cancer

    PubMed Central

    Ni, Ran; Huang, Yongjie; Wang, Jing

    2015-01-01

    Background Accumulating evidence has emphasized causative links between aberrant microRNA (miR) expression patterns and cancer development. Abnormally expressed miRNA-98 (miR-98) was found in certain types of human cancers. The biological roles of miR-98 in lung cancer, however, remain largely undefined. Methods We evaluated the expression of miR-98 in normal lung tissues, lung cancer tissues, normal human bronchial epithelial cells, and lung cancer cells using quantitative real-time polymerase chain reaction. Effect of miR-98 on proliferation of lung cancer cells was investigated using MTT assay and colony formation assay. Transwell assay was used to assess the effects of miR-98 on migration and invasion of lung cancer cells. Whether miR-98 targets the 3′-untranslated region (3′-UTR) of integrin β3 (ITGB3) coding gene ITGB3 mRNA was ascertained using luciferase reporter assay. Finally, we transplanted miR-98 expressing A549 cells into nude mice to observe the effect of miR-98 on tumor growth in vivo. Results We confirmed that miR-98 was frequently low expressed in lung cancer tissues and human lung cancer cells. Reintroduction of miR-98 into lung cancer cells inhibited cell proliferation, migration, and invasion in vitro and suppressed tumor formation in a nude mouse model. Furthermore, we identified that miR-98 exerted inhibitory roles by directly binding to 3′-UTR of ITGB3 mRNA, thus negatively regulated the expression of ITGB3. Interestingly, upon restoring the expression of ITGB3, the effect of miR-98 on cell proliferation was partially reversed. Conclusion Our findings suggest that miR-98 prevents proliferation, migration, and invasion of lung cancer cells by directly binding to the 3′-UTR of ITGB3 mRNA and could be a promising treatment option in anticancer therapy. PMID:26445551

  20. Astaxanthin Inhibits Proliferation and Induces Apoptosis and Cell Cycle Arrest of Mice H22 Hepatoma Cells.

    PubMed

    Shao, Yiye; Ni, Yanbo; Yang, Jing; Lin, Xutao; Li, Jun; Zhang, Lixia

    2016-01-01

    BACKGROUND It is widely recognized that astaxanthin (ASX), a member of the carotenoid family, has strong biological activities including antioxidant, anti-inflammation, and immune-modulation activities. Previous studies have confirmed that ASX can effectively inhibit hepatoma cells in vitro. MATERIAL AND METHODS MTT was used to assay proliferation of mice H22 cells, and flow cytometry was used to determine apoptosis and cell cycle arrest of H22 cells in vitro and in vivo. Moreover, anti-tumor activity of ASX was observed in mice. RESULTS ASX inhibited the proliferation of H22 cells, promoted cell necrosis, and induced cell cycle arrest in G2 phase in vitro and in vivo. CONCLUSIONS This study indicated that ASX can inhibit proliferation and induce apoptosis and cell cycle arrest in mice H22 hepatoma cells in vitro and in vivo. PMID:27333866

  1. Astaxanthin Inhibits Proliferation and Induces Apoptosis and Cell Cycle Arrest of Mice H22 Hepatoma Cells

    PubMed Central

    Shao, Yiye; Ni, Yanbo; Yang, Jing; Lin, Xutao; Li, Jun; Zhang, Lixia

    2016-01-01

    Background It is widely recognized that astaxanthin (ASX), a member of the carotenoid family, has strong biological activities including antioxidant, anti-inflammation, and immune-modulation activities. Previous studies have confirmed that ASX can effectively inhibit hepatoma cells in vitro. Material/Methods MTT was used to assay proliferation of mice H22 cells, and flow cytometry was used to determine apoptosis and cell cycle arrest of H22 cells in vitro and in vivo. Moreover, anti-tumor activity of ASX was observed in mice. Results ASX inhibited the proliferation of H22 cells, promoted cell necrosis, and induced cell cycle arrest in G2 phase in vitro and in vivo. Conclusions This study indicated that ASX can inhibit proliferation and induce apoptosis and cell cycle arrest in mice H22 hepatoma cells in vitro and in vivo. PMID:27333866

  2. Apoptosis and inhibition of proliferation of cancer cells induced by cordycepin

    PubMed Central

    TIAN, XUEWEN; LI, YUJIAN; SHEN, YINYU; LI, QIAOQIAO; WANG, QINGLU; FENG, LIANSHI

    2015-01-01

    Cordycepin, a 3-deoxyadenosine, is the predominant functional component of the fungus Cordyceps militaris, a traditional Chinese medicine. Previous studies investigating the inhibition of cancer cells by cordycepin identified that it not only promotes cell apoptosis, but also controls cell proliferation. Furthermore, studies have elucidated the molecular mechanisms of inhibiting cell proliferation by cordycepin binding the A3 adenosine receptor, activating G protein, inhibiting cAMP formation, decreasing glycogen synthase kinase-3β/β-catenin activation and suppressing cyclin D1 and c-myc expression. The most significant signaling pathway in which cell apoptosis is induced by cordycepin is the caspase pathway. Cordycepin induces cell apoptosis via binding the DR3 receptor and consequently activating caspase-8/-3. Taken together, these studies demonstrate that cordycepin may be used as a natural medicine, as it can not only control tumor cell proliferation, but also induce cancer cell apoptosis. PMID:26622539

  3. miR-613 inhibits proliferation and invasion of breast cancer cell via VEGFA.

    PubMed

    Wu, Junzhao; Yuan, Peng; Mao, Qixin; Lu, Peng; Xie, Tian; Yang, Hanzhao; Wang, Chengzheng

    2016-09-01

    MicroRNAs (miRNAs) play important roles in the pathogenesis of many types of cancers by negatively regulating gene expression at posttranscriptional level. However, the role of microRNAs in breast cancer, has remained elusive. Here, we identified that miR-613 inhibits breast cancer cell proliferation by negatively regulates its target gene VEGFA. In breast cancer cell lines, CCK-8 proliferation assay indicated that the cell proliferation was inhibited by miR-613, while miR-613 inhibitor significantly promoted the cell proliferation. Transwell assay showed that miR-613 mimics significantly inhibited the migration and invasion of breast cancer cells, whereas miR-613 inhibitors significantly increased cell migration and invasion. Luciferase assays confirmed that miR-613 directly bound to the 3' untranslated region of VEGFA, and western blotting showed that miR-613 suppressed the expression of VEGFA at the protein levels. This study indicated that miR-613 negatively regulates VEGFA and inhibits proliferation and invasion of breast cancer cell lines. Thus, miR-613 may represent a potential therapeutic molecule for breast cancer intervention. PMID:27449609

  4. Region-Specific Activation of oskar mRNA Translation by Inhibition of Bruno-Mediated Repression

    PubMed Central

    Kim, Goheun; Pai, Chin-I; Sato, Keiji; Person, Maria D.; Nakamura, Akira; Macdonald, Paul M.

    2015-01-01

    A complex program of translational repression, mRNA localization, and translational activation ensures that Oskar (Osk) protein accumulates only at the posterior pole of the Drosophila oocyte. Inappropriate expression of Osk disrupts embryonic axial patterning, and is lethal. A key factor in translational repression is Bruno (Bru), which binds to regulatory elements in the osk mRNA 3′ UTR. After posterior localization of osk mRNA, repression by Bru must be alleviated. Here we describe an in vivo assay system to monitor the spatial pattern of Bru-dependent repression, separate from the full complexity of osk regulation. This assay reveals a form of translational activation—region-specific activation—which acts regionally in the oocyte, is not mechanistically coupled to mRNA localization, and functions by inhibiting repression by Bru. We also show that Bru dimerizes and identify mutations that disrupt this interaction to test its role in vivo. Loss of dimerization does not disrupt repression, as might have been expected from an existing model for the mechanism of repression. However, loss of dimerization does impair regional activation of translation, suggesting that dimerization may constrain, not promote, repression. Our work provides new insight into the question of how localized mRNAs become translationally active, showing that repression of osk mRNA is locally inactivated by a mechanism acting independent of mRNA localization. PMID:25723530

  5. Piperlongumine inhibits proliferation and survival of Burkitt lymphoma in vitro

    PubMed Central

    Han, Seong-Su; Son, Dong-Ju; Yun, Hwakyung; Kamberos, Natalie L.; Janz, Siegfried

    2013-01-01

    Piperlongumine (PL), a pepper plant alkaloid from Piper longum, kills solid tumor cells in a highly selective, potent fashion. To evaluate whether PL may have similar effects on malignant blood cells, we determined the efficacy with which PL inhibits the B-lymphocyte derived neoplasm, Burkitt lymphoma (BL). Low micromolar concentrations of PL (IC50 = 2.8 × 8.5 μM) curbed growth and survival of two EBV+ BL cell lines (Daudi, Raji) and two EBV− BL cell lines (Ramos, DG-75), but left normal peripheral blood B-lymphocytes unharmed. PL-dependent cytotoxicity was effected in part by reduced NF-κB and MYC activity, with the former being caused by inhibition of IκBα degradation, nuclear translocation of p65, and binding of NF-κB dimers to cognate DNA sequences in gene promoters. In 4 of 4 BL cell lines, the NF-κB/MYC-regulated cellular target genes, E2F1 and MYB, were down regulated, while the stress sensor gene, GADD45B, was up regulated. The EBV-encoded oncogene, LMP-1, was suppressed in Daudi and Raji cells. Considering that NF-κB, MYC and LMP-1 play a crucial role in the biology of many blood cancers including BL, our results provide a strong preclinical rationale for considering PL in new intervention approaches for patients with hematologic malignancies. PMID:23237561

  6. Peroxisome proliferator-activated receptor-gamma ligands inhibit proliferation and induce apoptosis in mantle cell lymphoma.

    PubMed

    Eucker, Jan; Sterz, Jan; Krebbel, Holger; Zavrski, Ivana; Kaiser, Martin; Zang, Chuanbing; Heider, Ulrike; Jakob, Christian; Elstner, Elena; Sezer, Orhan

    2006-08-01

    Peroxisome proliferator-activated receptor-gamma, a nuclear receptor and transcription factor, and its natural and synthetic ligands have become a focus of novel approaches to induction of apoptosis in solid tumors and hematologic malignancies, including malignant B-lineage cells. The effect on mantle cell lymphoma, a subtype with dismal prognosis, has not yet been analyzed. We investigated the effect of 15-deoxy-delta-12,14-prostaglandin J2 (15d-PGJ2), pioglitazone (PGZ) or rosiglitazone (RGZ) on human mantle cell lymphoma cell lines (GRANTA-519, Hbl-2 and JeKo-1). Mantle cell lymphoma cell lines exhibited a high expression of Peroxisome proliferator-activated receptor-gamma protein in Western blot analysis. MTT assays revealed anti-proliferative effects induced by both 15d-PGJ2, the natural activator of Peroxisome proliferator-activated receptor-gamma, and PGZ and RGZ, synthetic Peroxisome proliferator-activated receptor-gamma ligands, in a dose-dependent manner. At a dose of 50 micromol/l, 15d-PGJ2 induced growth inhibition in all cell lines. The anti-proliferative effect of PGZ and RGZ was slightly lower. Induction of apoptosis was indicated by annexin V staining. At a dose of 50 micromol/l, 15d-PGJ2 led to apoptosis in all cell lines (87-99%) after 48 h of incubation. Again, the apoptotic effect with thiazolidinediones was slightly lower at the same dose level. This is the first study evaluating Peroxisome proliferator-activated receptor-gamma expression and its therapeutic implications in human mantle cell lymphoma cells. Thiazolidinediones comprise anti-lymphoma activity in vitro and should be further explored for the treatment of mantle cell lymphoma. PMID:16926626

  7. Inhibition of Cell Proliferation by an Anti-EGFR Aptamer

    PubMed Central

    Li, Na; Nguyen, Hong Hanh; Byrom, Michelle; Ellington, Andrew D.

    2011-01-01

    Aptamers continue to receive interest as potential therapeutic agents for the treatment of diseases, including cancer. In order to determine whether aptamers might eventually prove to be as useful as other clinical biopolymers, such as antibodies, we selected aptamers against an important clinical target, human epidermal growth factor receptor (hEGFR). The initial selection yielded only a single clone that could bind to hEGFR, but further mutation and optimization yielded a family of tight-binding aptamers. One of the selected aptamers, E07, bound tightly to the wild-type receptor (Kd = 2.4 nM). This aptamer can compete with EGF for binding, binds to a novel epitope on EGFR, and also binds a deletion mutant, EGFRvIII, that is commonly found in breast and lung cancers, and especially in grade IV glioblastoma multiforme, a cancer which has for the most part proved unresponsive to current therapies. The aptamer binds to cells expressing EGFR, blocks receptor autophosphorylation, and prevents proliferation of tumor cells in three-dimensional matrices. In short, the aptamer is a promising candidate for further development as an anti-tumor therapeutic. In addition, Aptamer E07 is readily internalized into EGFR-expressing cells, raising the possibility that it might be used to escort other anti-tumor or contrast agents. PMID:21687663

  8. Equol inhibits proliferation of human gastric carcinoma cells via modulating Akt pathway

    PubMed Central

    Yang, Zhi-Ping; Zhao, Yan; Huang, Fang; Chen, Jie; Yao, Ya-Hong; Li, Jun; Wu, Xiao-Nan

    2015-01-01

    AIM: To investigate the anti-tumor effects of equol in gastric cancer cells and the underlying molecular mechanisms. METHODS: MGC-803 cells were employed for in vitro experiments in this study. Cells were treated with control (vehicle, 0.1% DMSO) or equol under specified dose titration or time courses. Cell viability was examined by MTS assay, and the levels of Ki67 were determined by qPCR and immunofluorescent assay. Changes in cell cycle distribution and apoptosis rate were detected by flow cytometry. The mRNA expression of cyclin E1 and P21WAF1 was determined by qPCR. The protein levels of cell cycle regulators, PARP and Caspase-3 cleavage, and the phosphorylation of Akt were examined by Western blot. In addition, to characterize the role of elevated Akt activation in the anti-tumor effect exerted by equol, Ly294002, a PI3K/AKT pathway inhibitor, was used to pretreat MGC-803 cells. RESULTS: Equol (5, 10, 20, 40, or 80 μmol/L) inhibited viability of MGC-803 cells in a dose- and time-dependent manner after treatment for 24, 36, or 48 h (P < 0.05 for all). Equol also decreased the mRNA (P < 0.05 for 12 and 24 h treatment) and protein levels of Ki67. Equol treatment significantly induced G0/G1 cell cycle arrest (P < 0.05), with the percentages of G0/G1 cells of 32.23% ± 3.62%, 36.31% ± 0.24%, 45.58% ± 2.29%, and 65.10% ± 2.04% for equol (0, 10, 20, or 30 μmol/L) treatment, respectively, accompanied by a significant decrease of CDK2/4 (P < 0.05 for 24 and 48 h treatment) and Cyclin D1/Cyclin E1 (P < 0.05), and an increased level of P21WAF1 (P < 0.05). A marked increase of apoptosis was observed, with the percentages of apoptotic cells of 5.01% ± 0.91%, 14.57% ± 0.99%, 37.40% ± 0.58%, and 38.46% ± 2.01% for equol (0, 5, 10, or 20 μmol/L) treatment, respectively, accompanied by increased levels of cleaved PARP and caspase-3. In addition, we found that equol treatment increased P-Akt (Ser473 and Thr308) at 12 and 24 h compared to vehicle-treated control

  9. hnRNP-Q1 represses nascent axon growth in cortical neurons by inhibiting Gap-43 mRNA translation

    PubMed Central

    Williams, Kathryn R.; McAninch, Damian S.; Stefanovic, Snezana; Xing, Lei; Allen, Megan; Li, Wenqi; Feng, Yue; Mihailescu, Mihaela Rita; Bassell, Gary J.

    2016-01-01

    Posttranscriptional regulation of gene expression by mRNA-binding proteins is critical for neuronal development and function. hnRNP-Q1 is an mRNA-binding protein that regulates mRNA processing events, including translational repression. hnRNP-Q1 is highly expressed in brain tissue, suggesting a function in regulating genes critical for neuronal development. In this study, we have identified Growth-associated protein 43 (Gap-43) mRNA as a novel target of hnRNP-Q1 and have demonstrated that hnRNP-Q1 represses Gap-43 mRNA translation and consequently GAP-43 function. GAP-43 is a neuronal protein that regulates actin dynamics in growth cones and facilitates axonal growth. Previous studies have identified factors that regulate Gap-43 mRNA stability and localization, but it remains unclear whether Gap-43 mRNA translation is also regulated. Our results reveal that hnRNP-Q1 knockdown increased nascent axon length, total neurite length, and neurite number in mouse embryonic cortical neurons and enhanced Neuro2a cell process extension; these phenotypes were rescued by GAP-43 knockdown. Additionally, we have identified a G-quadruplex structure in the 5′ untranslated region of Gap-43 mRNA that directly interacts with hnRNP-Q1 as a means to inhibit Gap-43 mRNA translation. Therefore hnRNP-Q1–mediated repression of Gap-43 mRNA translation provides an additional mechanism for regulating GAP-43 expression and function and may be critical for neuronal development. PMID:26658614

  10. Inhibitory effect of reinioside C on vascular smooth muscle cells proliferation induced by angiotensin II via inhibiting NADPH oxidase-ROS-ENK1/2-NF-kappaB-AP-1 pathway.

    PubMed

    Hong, Dan; Bai, Yong-Ping; Shi, Rui-Zheng; Tan, Gui-Shan; Hu, Chang-Ping; Zhang, Guo-Gang

    2014-09-01

    The proliferation of vascular smooth muscle cells (VSMCs) induced by angiotensin II (Ang II) plays a vital role in the pathogenesis of arteriosclerosis and restenosis. In the present study, the effect of reinioside C, a main active ingredient of Polygala fallax Hemsl, on proliferation of VSMCs induced by Ang II was investigated. It was found that Ang II (1 microM) markedly stimulated proliferation of VSMCs. Pretreatment of reinioside C (3, 10 or 30 microM) concentration-dependently inhibited the proliferative effect of Ang II. To determine the possible mechanism, NADPH oxidase subunits (Nox-1, Nox-4) mRNA expression, intracellular ROS level, phosphorylation of ERK1/2, NF-kappaB activity, and mRNA expression of AP-1 subunits (c-fos, c-jun) and c-myc were measured. The results demonstrated that reinioside C attenuated Ang II-induced NADPH oxidase mRNA expression, generation of ROS, ERK1/2 phosphorylation, activation of NF-kappaB, and mRNA expression of AP-1 and c-myc in VSMCs in a concentration-dependent manner. The effects of Ang II were also inhibited by diphenyleneiodonium (DPI, the NADPH oxidase inhibitor), PD98059 (the ERK1/2 inhibitor) and pyrrolidine dithiocarbamate (PDTC, the NF-kappaB inhibitor). These results suggest reinioside C attenuates Ang II-induced proliferation of VSMCs by inhibiting NADPH oxidase-ROS-ERK1/2-NF-kappaB-AP-1 pathway. PMID:25272943

  11. Heparin fragments inhibit human vascular smooth muscle cell proliferation in vitro

    SciTech Connect

    Selden, S.C.; Johnson, W.V.; Maciag, T.

    1986-03-01

    The authors have examined the effect of heparin on human abdominal aortic smooth muscle cell growth. Cell proliferation was inhibited by more than 90% at a concentration of 20 ..mu..g/ml in a 12 day growth assay using heparin from Sigma, Upjohn or Calbiochem. Additionally, 200 ..mu..g/ml Upjohn heparin inhibits /sup 3/H-thymidine incorporation by 50% in short term assays using serum or purified platelet-derived growth factor (25-100ng/ml) to initiate the cell cycle. Homogeneous size classes of heparin fragments were prepared by nitrous acid cleavage and BioGel P-10 filtration chromatography. Deca-, octa-, hexa-, tetra-, and di-saccharides inhibited proliferation by 90% at concentrations of 280, 320, 260, 180 and 100 ..mu..g/ml, respectively, in a 12 day growth assay. These data confirm the work of Castellot et.al. and extend the range of inhibitory fragments down to the tetra- and di-saccharide size. These data suggest, therefore, that di-saccharide subunit of heparin is sufficient to inhibit vascular smooth muscle cell proliferation. The authors are now examining the role of the anhydromannose moiety on the reducing end of the nitrous acid generated fragments as a possible mediator of heparin-induced inhibition of vascular smooth muscle cell proliferation.

  12. Inhibition of GLI1 Expression by Targeting the CRD-BP-GLI1 mRNA Interaction Using a Specific Oligonucleotide.

    PubMed

    Mehmood, Kashif; Akhtar, Daud; Mackedenski, Sebastian; Wang, Chuyi; Lee, Chow H

    2016-06-01

    The stabilization of glioma-associated oncogene 1 (GLI1) mRNA by coding region determinant binding protein (CRD-BP) through the Wnt/β-catenin signaling pathway is implicated in the proliferation of colorectal cancer and basal cell carcinoma. Here, we set out to characterize the physical interaction between CRD-BP and GLI1 mRNA so as to find inhibitors for such interaction. Studies using CRD-BP variants with a point mutation in the GXXG motif at each KH domain showed that KH1 and KH2 domain are critical for the binding of GLI1 RNA. The smallest region of GLI1 RNA binding to CRD-BP was mapped to nucleotides (nts) 320-380. A 37-nt S1 RNA sense oligonucleotide, containing two distinct stem-loops present in nts 320-380 of GLI1 RNA, was found to be effective in blocking CRD-BP-GLI1 RNA interaction. Studies using various competitor RNAs with modifications to S1 RNA oligonucleotide further displayed that both the sequences and the structure of the two stem-loops are important for CRD-BP-GLI1 RNA binding. The role of the two-stem-loop motif in influencing CRD-BP-RNA interaction was further investigated in cells. The 2'-O-methyl derivative of the S1 RNA oligonucleotide significantly decreased GLI1, c-myc, and CD44 mRNA levels, in a panel of colon and breast cancer cells. The results from this study demonstrate the potential importance of the two-stem-loop motif as a target region for the inhibition of the CRD-BP-GLI1 RNA interaction and Hedgehog signaling pathway. Such results pave the way for the development of novel inhibitors that act by destabilizing the CRD-BP-GLI1 mRNA interaction. PMID:27036131

  13. MiR-181b targets Six2 and inhibits the proliferation of metanephric mesenchymal cells in vitro

    SciTech Connect

    Lyu, Zhongshi; Mao, Zhaomin; Wang, Honglian; Fang, Yin; Chen, Tielin; Wan, Qianya; Wang, Ming; Wang, Nian; Xiao, Jiangming; Wei, Hongyuan; Li, Xun; Liu, Yi; Zhou, Qin

    2013-11-01

    Highlights: •We do bio-informatics websites to analysis of Six2 3′UTR. •MiR181b is a putative miRNA which can targets Six2 3′UTR. •MiR-181b binding site in the 3′UTR of Six2 is functional. •MiR-181b suppresses MK3 cells cell proliferation by targeting Six2. -- Abstract: MicroRNAs (miRNAs) are small non-coding RNAs that down-regulate gene expression by binding to target mRNA for cleavage or translational repression, and play important regulatory roles in renal development. Despite increasing genes have been predicted to be miRNA targets by bioinformatic analysis during kidney development, few of them have been verified by experiment. The objective of our study is to identify the miRNAs targeting Six2, a critical transcription factor that maintains the mesenchymal progenitor pool via self-renewal (proliferation) during renal development. We initially analyzed the 3′UTR of Six2 and found 37 binding sites targeted by 50 putative miRNAs in the 3′UTR of Six2. Among the 50 miRNAs, miR-181b is the miRNAs predicted by the three used websites. In our study, the results of luciferase reporter assay, realtime-PCR and Western blot demonstrated that miR-181b directly targeted on the 3′UTR of Six2 and down-regulate the expression of Six2 at mRNA and protein levels. Furthermore, EdU proliferation assay along with the Six2 rescue strategy showed that miR-181b suppresses the proliferation of metanephric mesenchymal by targeting Six2 in part. In our research, we concluded that by targeting the transcription factor gene Six2, miR-181b inhibits the proliferation of metanephric mesenchymal cells in vitro and might play an important role in the formation of nephrons.

  14. Fermented red ginseng extract inhibits cancer cell proliferation and viability.

    PubMed

    Oh, Jisun; Jeon, Seong Bin; Lee, Yuri; Lee, Hyeji; Kim, Ju; Kwon, Bo Ra; Yu, Kang-Yeol; Cha, Jeong-Dan; Hwang, Seung-Mi; Choi, Kyung-Min; Jeong, Yong-Seob

    2015-04-01

    Red ginseng (Panax ginseng C.A. Meyer) is the most widely recognized medicinal herb due to its remedial effects in various disorders, such as cancers, diabetes, and heart problems. In this study, we investigated the anticancer effect of fermented red ginseng extract (f-RGE; provided by Jeonju Biomaterials Institute, Jeonju, South Korea) in a parallel comparison with the effect of nonfermented red ginseng extract (nf-RGE; control) on several cancer cell lines--MCF-7 breast cancer cells, HepG2 hepatocellular carcinoma cells, and reprogrammed MCF-7 cells (mimicking cancer stem cells). Cells were cultured at various concentrations of RGE (from 0.5 up to 5 mg/mL) and their viabilities and proliferative properties were examined. Our data demonstrate the following: (1) nf-RGE inhibited cell viability at ≥1 mg/mL for MCF-7 cells and ≥2 mg/mL for HepG2 cells, (2) in the presence of a carcinogenic agent, 12-O-tetradecanoylphorbol-13-acetate (TPA), nf-RGE treatment in combination with paclitaxel synergistically decreased MCF-7 as well as HepG2 cell viability, (3) f-RGE (which contained a greater level of Rg3 content) more effectively decreased the viability of MCF-7 and HepG2 cells compared to nf-RGE, and (4) f-RGE appeared more potent for inhibiting cancerous differentiation of reprogrammed MCF-7 cells in a synergistic fashion with paclitaxel, especially in the presence of TPA, compared to nf-RGE. These findings suggest that f-RGE treatment may be more effective for decreasing cancer cell survival by inducing apoptotic cell death and also presumably for preventing cancer stem cell differentiation compared to nf-RGE. PMID:25658580

  15. The Drosophila splicing regulator sex-lethal directly inhibits translation of male-specific-lethal 2 mRNA.

    PubMed Central

    Gebauer, F; Merendino, L; Hentze, M W; Valcárcel, J

    1998-01-01

    Male-specific expression of the protein male-specific-lethal 2 (MSL-2) controls dosage compensation in Drosophila. msl-2 gene expression is inhibited in females by Sex-lethal (SXL), an RNA binding protein known to regulate pre-mRNA splicing. An intron present at the 5' untranslated region (UTR) of msl-2 mRNA contains putative SXL binding sites and is retained in female flies. Here we show that SXL plays a dual role in the inhibition of msl-2 expression. Cotransfection of Drosophila Schneider cells with an SXL expression vector and a reporter containing the 5' UTR of msl-2 mRNA resulted in retention of the 5' UTR intron and efficient accumulation of the unspliced mRNA in the cytoplasm, where its translation was blocked by SXL, but not by the intron per se. Both splicing and translation inhibition by SXL were recapitulated in vitro and found to be dependent upon SXL binding to high-affinity sites within the intron, showing that SXL directly regulates these events. Our data reveal a coordinated mechanism for the regulation of msl-2 expression by the same regulatory factor: SXL enforces intron retention in the nucleus and subsequent translation inhibition in the cytoplasm. PMID:9570314

  16. IFN-α Induces Transcription of Hypoxia-Inducible Factor-1α to Inhibit Proliferation of Human Endothelial Cells1

    PubMed Central

    Gerber, Scott A.; Pober, Jordan S.

    2009-01-01

    Expression of hypoxia-inducible factor (HIF)-1α, a transcription factor subunit increased by protein stabilization in response to hypoxia, is increased in human endothelial cells (ECs) by IFN-α under normoxic conditions. IFN-α increases HIF-1α transcript levels within 2 h by up to 50% and doubles HIF-1α protein expression. Based on pharmacological inhibition studies, the increase in HIF-1α mRNA involves new transcription, is independent of new protein synthesis, and requires JAK signaling. Protein knockdown by small interfering RNA confirms the involvement of JAK1 and TYK2, as well of IFN-stimulated gene factor 3 (ISGF3). IFN-γ does not significantly induce HIF-1α mRNA, but increases the magnitude and duration of the IFN-α effect. IFN-α-induced HIF-1α protein translocates to the nucleus and can bind to hypoxia response elements in DNA. However, IFN-α treatment fails to induce transcription of several prototypic HIF-responsive genes (VEGF-A, PPARγ, and prostacyclin synthase) due to an insufficient increase in HIF-1α protein levels. Although certain other HIF-responsive genes (PHD3 and VEGF-C) are induced following IFN-α and/or IFN-γ treatment, these responses are not inhibited by siRNA knockdown of HIF-1α. Additionally, IFN-α induction of ISGF3-dependent genes involved in innate immunity (viperin, OAS2, and CXCL10) are also unaffected by knockdown of HIF-1α. Interestingly, knockdown of HIF-1α significantly reduces the capacity of IFN-α to inhibit endothelial cell proliferation. We conclude that IFN-α induces the transcription of HIF-1α in human endothelial cells though a JAK-ISGF3 pathway under normoxic conditions, and that this response contributes to the antiproliferative activity of this cytokine. PMID:18606657

  17. Newborn Hypoxia/Anoxia Inhibits Cardiomyocyte Proliferation and Decreases Cardiomyocyte Endowment in the Developing Heart: Role of Endothelin-1

    PubMed Central

    Paradis, Alexandra N.; Gay, Maresha S.; Wilson, Christopher G.; Zhang, Lubo

    2015-01-01

    In the developing heart, cardiomyocytes undergo terminal differentiation during a critical window around birth. Hypoxia is a major stress to preterm infants, yet its effect on the development and maturation of the heart remains unknown. We tested the hypothesis in a rat model that newborn anoxia accelerates cardiomyocyte terminal differentiation and results in reduced cardiomyocyte endowment in the developing heart via an endothelin-1-dependent mechanism. Newborn rats were exposed to anoxia twice daily from postnatal day 1 to 3, and hearts were isolated and studied at postnatal day 4 (P4), 7 (P7), and 14 (P14). Anoxia significantly increased HIF-1α protein expression and pre-proET-1 mRNA abundance in P4 neonatal hearts. Cardiomyocyte proliferation was significantly decreased by anoxia in P4 and P7, resulting in a significant reduction of cardiomyocyte number per heart weight in the P14 neonates. Furthermore, the expression of cyclin D2 was significantly decreased due to anoxia, while p27 expression was increased. Anoxia has no significant effect on cardiomyocyte binucleation or myocyte size. Consistently, prenatal hypoxia significantly decreased cardiomyocyte proliferation but had no effect on binucleation in the fetal heart. Newborn administration of PD156707, an ETA-receptor antagonist, significantly increased cardiomyocyte proliferation at P4 and cell size at P7, resulting in an increase in the heart to body weight ratio in P7 neonates. In addition, PD156707 abrogated the anoxia-mediated effects. The results suggest that hypoxia and anoxia via activation of endothelin-1 at the critical window of heart development inhibits cardiomyocyte proliferation and decreases myocyte endowment in the developing heart, which may negatively impact cardiac function later in life. PMID:25692855

  18. Piperine inhibits platelet-derived growth factor-BB-induced proliferation and migration in vascular smooth muscle cells.

    PubMed

    Lee, Kang Pa; Lee, Kwan; Park, Won-Hwan; Kim, Hyuck; Hong, Heeok

    2015-02-01

    The proliferation and migration of vascular smooth muscle cells (VSMCs) in blood vessels are important in the pathogenesis of vascular disorders such as atherosclerosis and restenosis. Piperine, a major component of black pepper, has antioxidant, anticancer, and anti-inflammatory activity. However, the antiatherosclerotic effects of piperine have not been investigated. In this study, the effects of piperine on platelet-derived growth factor (PDGF)-BB-induced proliferation and migration of VSMCs were investigated. The antiproliferative effects of piperine were determined using MTT assays, cell counting, real-time polymerase chain reaction, and western blots. Our results showed that piperine significantly attenuated the proliferation of VSMCs by increasing the expression of p27(kip1), regulating the mRNA expression of cell cycle enzymes (cyclin D, cyclin E, and PCNA), and decreasing the phosphorylation of extracellular signal-regulated kinase (ERK)1/2 in a noncytotoxic concentration-dependent manner (30-100 μM). Moreover, we examined the effects of piperine on the migration of PDGF-BB-stimulated VSMCs, as determined by the Boyden chamber assay, H2DCFDA staining, and western blots. Our results showed that 100 μM piperine decreased cell migration, the production of reactive oxygen species (ROS), and phosphorylation of the p38 mitogen-activated protein kinase (MAPK). Taken together, our results suggest that piperine inhibits PDGF-BB-induced proliferation and the migration of VSMCs by inducing cell cycle arrest and suppressing MAPK phosphorylation and ROS. These findings suggest that piperine may be beneficial for the treatment of vascular-related disorders and diseases. PMID:25384161

  19. Fatostatin Inhibits Cancer Cell Proliferation by Affecting Mitotic Microtubule Spindle Assembly and Cell Division.

    PubMed

    Gholkar, Ankur A; Cheung, Keith; Williams, Kevin J; Lo, Yu-Chen; Hamideh, Shadia A; Nnebe, Chelsea; Khuu, Cindy; Bensinger, Steven J; Torres, Jorge Z

    2016-08-12

    The sterol regulatory element-binding protein (SREBP) transcription factors have become attractive targets for pharmacological inhibition in the treatment of metabolic diseases and cancer. SREBPs are critical for the production and metabolism of lipids and cholesterol, which are essential for cellular homeostasis and cell proliferation. Fatostatin was recently discovered as a specific inhibitor of SREBP cleavage-activating protein (SCAP), which is required for SREBP activation. Fatostatin possesses antitumor properties including the inhibition of cancer cell proliferation, invasion, and migration, and it arrests cancer cells in G2/M phase. Although Fatostatin has been viewed as an antitumor agent due to its inhibition of SREBP and its effect on lipid metabolism, we show that Fatostatin's anticancer properties can also be attributed to its inhibition of cell division. We analyzed the effect of SREBP activity inhibitors including Fatostatin, PF-429242, and Betulin on the cell cycle and determined that only Fatostatin possessed antimitotic properties. Fatostatin inhibited tubulin polymerization, arrested cells in mitosis, activated the spindle assembly checkpoint, and triggered mitotic catastrophe and reduced cell viability. Thus Fatostatin's ability to inhibit SREBP activity and cell division could prove beneficial in treating aggressive types of cancers such as glioblastomas that have elevated lipid metabolism and fast proliferation rates and often develop resistance to current anticancer therapies. PMID:27378817

  20. Inhibition of cancer cell proliferation by midazolam by targeting transient receptor potential melastatin 7.

    PubMed

    Dou, Yunling; Li, Yuan; Chen, Jingkao; Wu, Sihan; Xiao, Xiao; Xie, Shanshan; Tang, Lipeng; Yan, Min; Wang, Youqiong; Lin, Jun; Zhu, Wenbo; Yan, Guangmei

    2013-03-01

    Transient receptor potential melastatin 7 (TRPM7), a Ca(2+)-permeable channel, has been demonstrated to be present in cancer cells and involved in their growth and proliferation. The present study used midazolam, a benzodiazepine class anesthesic, to pharmacologically intervene in the expression of TRPM7 and to inhibit cancer cell proliferation. Midazolam significantly inhibited the growth and proliferation of FaDu human hypopharyngeal squamous cell carcinoma cells, concurring with the induction of G(0)/G(1) cell cycle arrest and blockage of Rb activation. Central-type and peripheral-type benzodiazepine receptor antagonists did not abrogate proliferation inhibition by midazolam, while the specific TRPM7 agonist bradykinin reversed this effect. In addition, other benzodiazepines, diazepam and clonazepam also exhibited anti-proliferative activities. The inhibitory activity on cancer cell growth and proliferation, combined with the TRPM-dependent mechanism, reveals the anticancer potential of midazolam as a TRPM7 inhibitor and supports the suggestion that TRPM7 is a valuable target for pharmaceutical intervention. PMID:23426784

  1. miR-599 Inhibits Vascular Smooth Muscle Cells Proliferation and Migration by Targeting TGFB2

    PubMed Central

    Xie, Baodong; Zhang, Chunfeng; Kang, Kai; Jiang, Shulin

    2015-01-01

    Aberrant proliferation and migration of vascular smooth muscle cells (VSMCs) play a crucial role in the pathogenesis of cardiovascular diseases including coronary heart disease, restenosis and atherosclerosis. MicroRNAs are a class of small, non-coding and endogenous RNAs that play critical roles in VSMCs function. In this study, we showed that PDGF-bb, as a stimulant, promoted VSMCs proliferation and suppressed the expression of miR-599. Moreover, overexpression of miR-599 inhibited VSMCs proliferation and also suppressed the PCNA and ki-67 expression. In addition, we demonstrated that ectopic expression of miR-599 repressed the VSMCs migration. We also showed that miR-599 inhibited type I collagen, type V collagen and proteoglycan expression. Furthermore, we identified TGFb2 as a direct target gene of miR-599 in VSMCs. Overexpression of TGFb2 reversed miR-599-induced inhibition of VSMCs proliferation and type I collagen, type V collagen and proteoglycan expression. In conclusion, our findings suggest miR-599 plays a crucial role in controlling VSMCs proliferation and matrix gene expression by regulating TGFb2 expression. PMID:26551255

  2. Yi Qi Qing Re Gao-containing serum inhibits lipopolysaccharide-induced rat mesangial cell proliferation by suppressing the Wnt pathway and TGF-β1 expression

    PubMed Central

    YANG, LIPING; SUN, XUEYAN; ZHAN, YONGLI; LIU, HUIJIE; WEN, YUMIN; MAO, HUIMIN; DONG, XI; LI, PING

    2016-01-01

    The aim of the present study was to investigate the effect of Yi Qi Qing Re Gao-containing serum (YQ-S) on rat mesangial cell (MC) proliferation and to investigate the underlying mechanism. MCs were divided into the control, lipopolysaccharide (LPS)-stimulated, YQ-S and fosinopril-containing serum (For-S) groups, and cultured for 48 h. An MTT assay was used to evaluate the proliferation of MCs. In addition, reverse transcription-quantitative polymerase chain reaction and western blot analysis were conducted to detect the expression levels of Wnt4, β-catenin and transforming growth factor (TGF)-β1 in MCs. The results indicated that YQ-S inhibited LPS-induced MC proliferation. The Wnt4 and TGF-β1 mRNA expression levels were reduced in the YQ-S group (P<0.01 or P<0.05). Furthermore, the Wnt4, β-catenin and TGF-β1 protein expression levels were suppressed in the YQ-S group (P<0.01 or P<0.05). Therefore, YQ-S appears to inhibit MC proliferation, and its mechanism may involve the inhibition of the Wnt signaling pathway and downregulation of TGF-β1 expression. PMID:27073458

  3. Fangchinoline inhibits cell proliferation via Akt/GSK-3beta/ cyclin D1 signaling and induces apoptosis in MDA-MB-231 breast cancer cells.

    PubMed

    Wang, Chang-Dong; Yuan, Cheng-Fu; Bu, You-Quan; Wu, Xiang-Mei; Wan, Jin-Yuan; Zhang, Li; Hu, Ning; Liu, Xian-Jun; Zu, Yong; Liu, Ge-Li; Song, Fang-Zhou

    2014-01-01

    Fangchinoline (Fan) inhibits cell proliferation and induces apoptosis in several cancer cell lines. The effects of Fan on cell growth and proliferation in breast cancer cells remain to be elucidated. Here, we show that Fan inhibited cell proliferation in the MDA-MB-231 breast cancer cell line through suppression of the AKT/Gsk- 3beta/cyclin D1 signaling pathway. Furthermore, Fan induced apoptosis by increasing the expression of Bax (relative to Bcl-2), active caspase 3 and cytochrome-c. Fan significantly inhibited cell proliferation of MDA- MB-231 cells in a concentration and time dependent manner as determined by MTT assay. Flow cytometry analysis demonstrated that Fan treatment of MDA-MB-231 cells resulted in cell cycle arrest at the G1 phase, which correlated with apparent downregulation of both mRNA and protein levels of both PCNA and cyclin D1. Further analysis demonstrated that Fan decreased the phosphorylation of AKT and GSK-3beta. In addition, Fan up-regulated active caspase3, cytochrome-c protein levels and the ratio of Bax/Bcl-2, accompanied by apoptosis. Taken together, these results suggest that Fan is a potential natural product for the treatment of breast cancer. PMID:24568493

  4. Dihydroartemisinin inhibits cell proliferation via AKT/GSK3β/cyclinD1 pathway and induces apoptosis in A549 lung cancer cells

    PubMed Central

    Liao, Kui; Li, Juan; Wang, Zhiling

    2014-01-01

    Lung cancer is the most common cause of cancer-related death in the world. The main types of lung cancer are small cell lung carcinoma (SCLC) and non-small-cell lung carcinoma (NSCLC); non small cell lung carcinoma (NSCLC) includes squamous cell carcinoma (SCC), adenocarcinoma and large cell carcinoma, Non small cell lung carcinoma accounts for about 80% of the total lung cancer cases. Dihydroartemisinin (DHA) inhibits cell proliferation and induces apoptosis in several cancer cell lines. The effects of DHA on cell growth and proliferation in lung cancer cells remain to be elucidated. Here, we demonstrate that DHA inhibited cell proliferation in the A549 lung cancer cell line through suppression of the AKT/Gsk-3β/cyclin D1 signaling pathway. DHA significantly inhibited cell proliferation of A549 cells in a concentration and time dependent manner as determined by MTS assay. Flow cytometry analysis demonstrated that DHA treatment of A549 cells resulted in cell cycle arrest at the G1 phase, which correlated with apparent downregulation of both mRNA and protein levels of both PCNA and cyclin D1. These results suggest that DHA is a potential natural product for the treatment of lung cancer. PMID:25674233

  5. Inhibition of colonic cancer cell proliferation and COX2 by oats avenanthramides (Avns)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    High intake of whole grain foods is associated with reduced risk of colon cancer, but the mechanism underlying this protection has yet to be elucidated. Avns are polyphenols unique to oats. We have reported that Avns inhibited pro-inflammatory cytokines and vascular smooth muscle cell proliferation....

  6. Minocycline, a tetracycline derivative, is neuroprotective against excitotoxicity by inhibiting activation and proliferation of microglia.

    PubMed

    Tikka, T; Fiebich, B L; Goldsteins, G; Keinanen, R; Koistinaho, J

    2001-04-15

    Minocycline, a semisynthetic tetracycline derivative, protects brain against global and focal ischemia in rodents. We examined whether minocycline reduces excitotoxicity in primary neuronal cultures. Minocycline (0.02 microm) significantly increased neuronal survival in mixed spinal cord (SC) cultures treated with 500 microm glutamate or 100 microm kainate for 24 hr. Treatment with these excitotoxins induced a dose-dependent proliferation of microglia that was associated with increased release of interleukin-1beta (IL-1beta) and was followed by increased lactate dehydrogenase (LDH) release. The excitotoxicity was enhanced when microglial cells were cultured on top of SC cultures. Minocycline prevented excitotoxin-induced microglial proliferation and the increased release of nitric oxide (NO) metabolites and IL-1beta. Excitotoxins induced microglial proliferation and increased the release of NO metabolites and IL-1beta also in pure microglia cultures, and these responses were inhibited by minocycline. In both SC and pure microglia cultures, excitotoxins activated p38 mitogen-activated protein kinase (p38 MAPK) exclusively in microglia. Minocycline inhibited p38 MAPK activation in SC cultures, and treatment with SB203580, a p38 MAPK inhibitor, but not with PD98059, a p44/42 MAPK inhibitor, increased neuronal survival. In pure microglia cultures, glutamate induced transient activation of p38 MAPK, and this was inhibited by minocycline. These findings indicate that the proliferation and activation of microglia contributes to excitotoxicity, which is inhibited by minocycline, an antibiotic used in severe human infections. PMID:11306611

  7. Lipocalin-2 inhibits osteoclast formation by suppressing the proliferation and differentiation of osteoclast lineage cells

    SciTech Connect

    Kim, Hyun-Ju; Yoon, Hye-Jin; Yoon, Kyung-Ae; Gwon, Mi-Ri; Jin Seong, Sook; Suk, Kyoungho; Kim, Shin-Yoon; Yoon, Young-Ran

    2015-06-10

    Lipocalin-2 (LCN2) is a member of the lipocalin superfamily and plays a critical role in the regulation of various physiological processes, such as inflammation and obesity. In this study, we report that LCN2 negatively modulates the proliferation and differentiation of osteoclast precursors, resulting in impaired osteoclast formation. The overexpression of LCN2 in bone marrow-derived macrophages or the addition of recombinant LCN2 protein inhibits the formation of multinuclear osteoclasts. LCN2 suppresses macrophage colony-stimulating factor (M-CSF)-induced proliferation of osteoclast precursor cells without affecting their apoptotic cell death. Interestingly, LCN2 decreases the expression of the M-CSF receptor, c-Fms, and subsequently blocks its downstream signaling cascades. In addition, LCN2 inhibits RANKL-induced osteoclast differentiation and attenuates the expression of c-Fos and nuclear factor of activated T cells c1 (NFATc1), which are important modulators in osteoclastogenesis. Mechanistically, LCN2 inhibits NF-κB signaling pathways, as demonstrated by the suppression of IκBα phosphorylation, nuclear translocation of p65, and NF-κB transcriptional activity. Thus, LCN2 is an anti-osteoclastogenic molecule that exerts its effects by retarding the proliferation and differentiation of osteoclast lineage cells. - Highlights: • LCN2 expression is regulated during osteoclast development. • LCN2 suppresses M-CSF-mediated osteoclast precursor proliferation. • LCN2 inhibits RANKL-induced osteoclast differentiation.

  8. Expression of K6W-ubiquitin inhibits proliferation of human lens epithelial cells

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ubiquitin-proteasome pathway plays an important role in controlling the cell cycle. The purpose of this study was to examine if expression of a dominant negative form of ubiquitin can inhibit the proliferation of lens epithelial cells. Dominant negative K6W-ubiquitin was expressed in cultured hu...

  9. DICHLOROACETIC ACID (DCA) INHIBITS PROLIFERATION AND APOPTOSIS IN NORMAL HEPATOCYTES OF MALE F344 RATS

    EPA Science Inventory

    Dichloroacetic acid (DCA} inhibits proliferation and apoptosis in nonnal hepatocytes of
    male F344 rats.

    Large segments of the population are chronically exposed to dichloroacetic acid (DCA}: DCA is a by product of the chlorine disinfection of drinking water, a metab...

  10. Antioxidant Activities and Inhibition of Cancer Cell Proliferation in Wild Strawberries

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fruit extracts from seventeen representatives of three species of strawberries (Fragaria virginiana Mill., F. chiloensis (L.) Mill., and F. x ananassa Duchesne ex Rozier) were tested for activities against free radicals, the activities of antioxidant enzymes and the ability to inhibit proliferation...

  11. Silibinin Inhibits HIV-1 Infection by Reducing Cellular Activation and Proliferation

    PubMed Central

    McClure, Janela; Lovelace, Erica S.; Elahi, Shokrollah; Maurice, Nicholas J.; Wagoner, Jessica; Dragavon, Joan; Mittler, John E.; Kraft, Zane; Stamatatos, Leonidis; Horton, Helen; De Rosa, Stephen C.; Coombs, Robert W.; Polyak, Stephen J.

    2012-01-01

    Purified silymarin-derived natural products from the milk thistle plant (Silybum marianum) block hepatitis C virus (HCV) infection and inhibit T cell proliferation in vitro. An intravenous formulation of silibinin (SIL), a major component of silymarin, displays anti-HCV effects in humans and also inhibits T-cell proliferation in vitro. We show that SIL inhibited replication of HIV-1 in TZM-bl cells, PBMCs, and CEM cells in vitro. SIL suppression of HIV-1 coincided with dose-dependent reductions in actively proliferating CD19+, CD4+, and CD8+ cells, resulting in fewer CD4+ T cells expressing the HIV-1 co-receptors CXCR4 and CCR5. SIL inhibition of T-cell growth was not due to cytotoxicity measured by cell cycle arrest, apoptosis, or necrosis. SIL also blocked induction of the activation markers CD38, HLA-DR, Ki67, and CCR5 on CD4+ T cells. The data suggest that SIL attenuated cellular functions involved in T-cell activation, proliferation, and HIV-1 infection. Silymarin-derived compounds provide cytoprotection by suppressing virus infection, immune activation, and inflammation, and as such may be relevant for both HIV mono-infected and HIV/HCV co-infected subjects. PMID:22848626

  12. Corosolic acid inhibits the proliferation of glomerular mesangial cells and protects against diabetic renal damage

    PubMed Central

    Li, Xiao-Qiang; Tian, Wen; Liu, Xiao-Xiao; Zhang, Kai; Huo, Jun-Cheng; Liu, Wen-Juan; Li, Ping; Xiao, Xiong; Zhao, Ming-Gao; Cao, Wei

    2016-01-01

    Diabetic nephropathy (DN) is one of the major complications of diabetes mellitus (DM). This study aimed to explore the effects of corosolic acid (CA) on the renal damage of DM and the mechanisms behind these effects. The renoprotective effect of CA was investigated in type 1 diabetic rats and db/db mice. The kidneys and glomerular mesangial cells (GMCs) were used to study the proliferation of GMCs by immunostaining and MTT assay. Further immunoblotting, siRNA, qPCR analysis, and detecting of NADPH oxidase activity and reactive oxygen species (ROS) generation were performed to explore relevant molecular mechanisms. In CA-treated diabetic animals, diabetes-induced albuminuria, increased serum creatinine and blood urea nitrogen were significantly attenuated, and glomerular hypertrophy, mesangial expansion and fibrosis were ameliorated. Furthermore, CA significantly inhibited proliferation of GMCs and phosphorylation of ERK1/2 and p38 MAPK in both diabetic animals and high glucose (HG)-induced GMCs. CA also normalized Δψm and inhibited HG-induced NADPH oxidase activity, ROS generation and NOX4, NOX2, p22phox and p47phox expression. More importantly, CA inhibited GMC proliferation mediated by NADPH/ERK1/2 and p38 MAPK signaling pathways. These findings suggest that CA exert the protective effect on DN by anti-proliferation resulted from inhibition of p38 MAPK- and NADPH-mediated inactivation of ERK1/2. PMID:27229751

  13. Oxidative stress-mediated inhibition of intestinal epithelial cell proliferation by silver nanoparticles.

    PubMed

    McCracken, Christie; Zane, Andrew; Knight, Deborah A; Hommel, Elizabeth; Dutta, Prabir K; Waldman, W James

    2015-10-01

    Given the increasing use of silver nanoparticles (Ag NP) by the food and food packaging industries, this study investigated potential consequences of Ag NP ingestion in intestinal epithelial C2BBe1 cells. Treatment of proliferating cells (<10,000 cells/cm(2)) with 0.25 μg/cm(2) (1.25 μg/mL) of 23 nm Ag NP for 24 h induced 15% necrotic cell death and an 80% reduction in metabolic activity and decreased the GSH/GSSG ratio, indicating oxidative stress. G2/M phase cell cycle arrest and complete inhibition of cell proliferation was also induced by Ag NP treatment. Simulated in vitro digestion of Ag NP prior to cell exposure required the use of slightly higher doses to induce the same toxicity, likely due to slower Ag dissolution. Treatment of cells with silica, titania, and ZnO NP partially inhibited cell proliferation, but inhibition at low doses was unique to Ag NP. These data suggest that Ag NP induces oxidative stress, cell cycle arrest, and the inhibition of cell proliferation. However, toxicity and induction of oxidative stress were not observed in confluent cells (>100,000 cells/cm(2)) treated with 10 μg/cm(2) (40-50 μg/mL) Ag NP, indicating that these cells are less sensitive to Ag NP. PMID:26196530

  14. Silencing of tripartite motif (TRIM) 29 inhibits proliferation and invasion and increases chemosensitivity to cisplatin in human lung squamous cancer NCI-H520 cells

    PubMed Central

    Liu, Chunxiao; Huang, Xiaoxi; Hou, Shengcai; Hu, Bin; Li, Hui

    2015-01-01

    Background TRIM29 belongs to the tripartite motif (TRIM) protein family. It has been reported to be a tumor suppressor or have oncogenic function in many cancer types. The aim of this study was to investigate whether downregulation of TRIM29 by small interfering ribonucleic acid (siRNA) could inhibit cell proliferation and invasion and increase chemosensitivity to cisplatin in human lung squamous cancer NCI-H520 cells in vitro. Methods We transformed TRIM29 siRNA into NCI-H520 cells. Real time reverse transcriptase polymerase chain reaction and Western blotting assay were employed to determine TRIM29 messenger (m)RNA and protein expressions. MTT assay was used to determine the cell proliferation. Transwell invasion assay was used to determine the cell invasion. An Annexin V-propidium iodide (AnnV/PI) staining apoptosis test was used for detecting apoptosis. Results TRIM29 siRNA could specifically and efficiently suppress TRIM29 expression at both mRNA and protein levels. Silencing of the TRIM29 by siRNA in NCI-H520 cells inhibited cell proliferation and invasion in vitro. TRIM29 knockdown resulted in chemosensitivity enhancement in NCI-H520 cells. Conclusion Downregulation of TRIM29 can lead to potent antitumor activity and chemosensitizing effect in human lung squamous cancer NCI-H520 cells. PMID:26273332

  15. MicroRNA-144 inhibits the proliferation, apoptosis, invasion, and migration of osteosarcoma cell line F5M2.

    PubMed

    Cui, Shao-Qian; Wang, Huan

    2015-09-01

    This study is aimed to investigate the role of microRNA-144 (miR-144) in osteosarcoma cell line F5M2 proliferation, apoptosis, invasion, and metastasis. Between 2007 and 2014, 66 cases of osteosarcoma samples in the corresponding adjacent normal tissue samples were selected from surgical resection or biopsy in the Department of Orthopedics, Shengjing Hospital, China Medical University. MiR-144 levels and Ezrin messenger RNA (mRNA) levels in osteosarcoma and the adjacent bone tissues were detected, and clinical and pathological features were analyzed. Exogenous miR-144 was transfected into human osteosarcoma cell lines at two different concentrations (low and high), and the expression levels of miR-144 and Ezrin protein between highly metastatic osteosarcoma cells and lowly metastatic osteosarcoma cells were compared. Real-time polymerase chain reaction (RT-PCR) and Western blot were used for detecting the expression levels of miR-144 or Ezrin protein, respectively. Cell proliferation was measured by methylthiazol tetrazolium (MTT) assay. Cell invasion and migration was evaluated by Transwell assays. Finally, flow cytometry was employed to determine the cell apoptosis. MiR-144 expression in osteosarcoma tissue was significantly lower than that in the surrounding normal bone tissue (P < 0.001), while Ezrin mRNA expression in osteosarcoma tissue was significantly higher than that in the surrounding normal bone tissue (P < 0.001); correlation analysis showed a significant negative correlation between miR-144 and Ezrin mRNA levels (r = 0.982, P < 0.001). MiR-144 and Ezrin mRNA expressions were significantly related with cell metastasis (P < 0.05) but were not related with other clinical factors such as gender, age, tumor location, tumor size, Enneking staging, and Dahlin's histological classification. The results of RT-PCR showed that the expression level of miR-144 in osteosarcoma cells increased after transfected with exogenous miR-144 mimics, and

  16. Protocatechuic aldehyde inhibits migration and proliferation of vascular smooth muscle cells and intravascular thrombosis

    SciTech Connect

    Moon, Chang Yoon; Ku, Cheol Ryong; Cho, Yoon Hee; Lee, Eun Jig

    2012-06-22

    Highlights: Black-Right-Pointing-Pointer Protocatechuic aldehyde (PCA) inhibits ROS production in VSMCs. Black-Right-Pointing-Pointer PCA inhibits proliferation and migration in PDGF-induced VSMCs. Black-Right-Pointing-Pointer PCA has anti-platelet effects in ex vivo rat whole blood. Black-Right-Pointing-Pointer We report the potential therapeutic role of PCA in atherosclerosis. -- Abstract: The migration and proliferation of vascular smooth muscle cells (VSMCs) and formation of intravascular thrombosis play crucial roles in the development of atherosclerotic lesions. This study examined the effects of protocatechuic aldehyde (PCA), a compound isolated from the aqueous extract of the root of Salvia miltiorrhiza, an herb used in traditional Chinese medicine to treat a variety of vascular diseases, on the migration and proliferation of VSMCs and platelets due to platelet-derived growth factor (PDGF). DNA 5-bromo-2 Prime -deoxy-uridine (BrdU) incorporation and wound-healing assays indicated that PCA significantly attenuated PDGF-induced proliferation and migration of VSMCs at a pharmacologically relevant concentration (100 {mu}M). On a molecular level, we observed down-regulation of the phosphatidylinositol 3-kinase (PI3K)/Akt and the mitogen-activated protein kinase (MAPK) pathways, both of which regulate key enzymes associated with migration and proliferation. We also found that PCA induced S-phase arrest of the VSMC cell cycle and suppressed cyclin D2 expression. In addition, PCA inhibited PDGF-BB-stimulated reactive oxygen species production in VSMCs, indicating that PCA's antioxidant properties may contribute to its suppression of PDGF-induced migration and proliferation in VSMCs. Finally, PCA exhibited an anti-thrombotic effect related to its inhibition of platelet aggregation, confirmed with an aggregometer. Together, these findings suggest a potential therapeutic role of PCA in the treatment of atherosclerosis and angioplasty-induced vascular restenosis.

  17. The Matricellular Protein CCN1 Suppresses Hepatocarcinogenesis by Inhibiting Compensatory Proliferation

    PubMed Central

    Chen, Chih-Chiun; Kim, Ki-Hyun; Lau, Lester F.

    2015-01-01

    Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related deaths worldwide, and is on the rise in the United States. Previous studies showed that the matricellular protein CCN1 (CYR61) is induced during hepatic injuries and functions to restrict and resolve liver fibrosis. Here we show that CCN1 suppresses hepatocarcinogenesis by inhibiting carcinogen-induced compensatory hepatocyte proliferation, thus limiting the expansion of damaged and potentially oncogenic hepatocytes. Consistent with tumor suppression, CCN1 expression is down-regulated in human HCC. Ccn1ΔHep mice with hepatocyte-specific deletion of Ccn1 suffer increased HCC tumor multiplicity induced by the hepatocarcinogen diethylnitrosoamine (DEN). Knockin mice (Ccn1dm/dm) that express an integrin α6β1-binding defective CCN1 phenocopied Ccn1ΔHep mice, indicating that CCN1 acts through its α6β1 binding sites in this context. CCN1 effectively inhibits EGFR-dependent hepatocyte proliferation through integrin α6-mediated accumulation of reaction oxygen species (ROS), thereby triggering p53 activation and cell cycle block. Consequently, Ccn1dm/dm mice exhibit diminished p53 activation and elevated compensatory hepatocyte proliferation, resulting in increased HCC. Furthermore, we show that a single dose of the EGFR inhibitor erlotinib delivered prior to DEN-induced injury was sufficient to block compensatory proliferation and annihilate development of HCC nodules observed 8 months later, suggesting potential chemoprevention by targeting CCN1-inhibitable EGFR-dependent hepatocyte proliferation. Together, these results show that CCN1 is an injury response protein that functions not only to restrict fibrosis in the liver, but also to suppress hepatocarcinogenesis by inhibiting EGFR-dependent hepatocyte compensatory proliferation. PMID:26028023

  18. TRAIL-receptor costimulation inhibits proximal TCR signaling and suppresses human T cell activation and proliferation.

    PubMed

    Lehnert, Corinna; Weiswange, Maxi; Jeremias, Irmela; Bayer, Carina; Grunert, Michaela; Debatin, Klaus-Michael; Strauss, Gudrun

    2014-10-15

    The TRAIL-receptor/TRAIL system originally described to induce apoptosis preferentially in malignant cells is also known to be involved in T cell homeostasis and the response to viral infections and autoimmune diseases. Whereas the expression of TRAIL on activated NK and T cells increases their cytotoxicity, induction of TRAIL on APCs can turn them into apoptosis inducers but might also change their immunostimulatory capacity. Therefore, we analyzed how TRAIL-receptor (TRAIL-R) costimulation is modulating TCR-mediated activation of human T cells. T cells triggered by rTRAIL in combination with anti-CD3 and -CD28 Abs exhibited a strong decrease in the expression of activation markers and Th1 and Th2 cytokines compared with CD3/CD28-activated T cells. Most importantly, proliferation of TRAIL-R costimulated T cells was strongly impaired, but no apoptosis was induced. Addition of exogenous IL-2 could not rescue T cells silenced by TRAIL-R costimulation, and TRAIL-mediated inhibition of T cell proliferation only prevented TCR-triggered proliferation but was ineffective if T cells were activated downstream of the TCR. Inhibition of T cell proliferation was associated with abrogation of proximal TCR signaling by inhibiting recruitment of TCR-associated signaling molecules to lipid rafts, followed by abrogation of protein tyrosine phosphorylation of ZAP70, phospholipase C-γ1, and protein kinase C-θ, and impaired nuclear translocation of NFAT, AP-1, and NF-κB. Most importantly, TRAIL-R costimulation efficiently inhibited alloantigen-induced T cell proliferation and CD3/28-induced activation and proliferation of autoreactive T cells derived from patients with Omenn syndrome, indicating that coactivation of TRAIL-R and TCR represents a mechanism to downmodulate T cell immune responses. PMID:25217163

  19. Proliferation and mRNA expression of absorptive villous cell markers and mineral transporters in prolactin-exposed IEC-6 intestinal crypt cells.

    PubMed

    Teerapornpuntakit, Jarinthorn; Wongdee, Kannikar; Thongbunchoo, Jirawan; Krishnamra, Nateetip; Charoenphandhu, Narattaphol

    2012-06-01

    During pregnancy and lactation, prolactin (PRL) enhances intestinal absorption of calcium and other minerals for fetal development and milk production. Although an enhanced absorptive efficiency is believed to mainly result from the upregulation of mineral transporters in the absorptive villous cells, some other possibilities, such as PRL-enhanced crypt cell proliferation and differentiation to increase the absorptive area, have never been ruled out. Here, we investigated cell proliferation and mRNA expression of mineral absorption-related genes in the PRL-exposed IEC-6 crypt cells. As expected, the cell proliferation was not altered by PRL. Inasmuch as the mRNA expressions of villous cell markers, including dipeptidylpeptidase-4, lactase and glucose transporter-5, were not increased, PRL was not likely to enhance crypt cell differentiation into the absorptive villous cells. In contrast to the previous findings in villous cells, PRL was found to downregulate the expression of calbindin-D(9k), claudin-3 and occludin in IEC-6 crypt cells, while having no effect on transient receptor potential vanilloid family channels-5/6, plasma membrane Ca(2+)-ATPase (PMCA)-1b and Na(+)/Ca(2+) exchanger-1 expression. In conclusion, IEC-6 crypt cells did not respond to PRL by increasing proliferation or differentiation into villous cells. The present results thus supported the previous hypothesis that PRL enhanced mineral absorption predominantly by increasing transporter expression and activity in the absorptive villous cells. PMID:22281785

  20. Inhibition of miR-29c promotes proliferation, and inhibits apoptosis and differentiation in P19 embryonic carcinoma cells

    PubMed Central

    CHEN, BIN; SONG, GUIXIAN; LIU, MING; QIAN, LINGMEI; WANG, LIHUA; GU, HAITAO; SHEN, YAHUI

    2016-01-01

    In our previous study, the upregulation of microRNA (miR)-29c was identified in the mother of a fetus with a congenital heart defect. However, the functional and regulatory mechanisms of miR-29c in the development of the heart remain to be elucidated. In the present study, the role and mechanism of miR-29c inhibition in heart development were investigated in an embryonic carcinoma cell model. Inhibition of miR-29c promoted proliferation, and suppressed the apoptosis and differentiation of P19 cells. It was also demonstrated that Wingless-related MMTV integration site 4 (Wnt4) was a target of miR-29c, determined using bioinformatic analysis combined with luciferase assays. The inhibition of miR-29c stimulated the WNT4/β-catenin pathway, promoting proliferation of the P19 cells, but suppressing their differentiation into cardiomyocytes. Furthermore, the inhibition of miR-29c promoted the expression of B cell lymphoma-2 and inhibited cell apoptosis. These results demonstrate the significance of miR-29c in the process of cardiac development and suggest that miR-29c dysregulation may be associated with the occurrence of CHD. Thus, miR-29c may have therapeutic potential in the future. PMID:26848028

  1. Overexpression of FABP3 inhibits human bone marrow derived mesenchymal stem cell proliferation but enhances their survival in hypoxia

    SciTech Connect

    Wang, Suna Zhou, Yifu; Andreyev, Oleg; Hoyt, Robert F.; Singh, Avneesh; Hunt, Timothy; Horvath, Keith A.

    2014-04-15

    Studying the proliferative ability of human bone marrow derived mesenchymal stem cells in hypoxic conditions can help us achieve the effective regeneration of ischemic injured myocardium. Cardiac-type fatty acid binding protein (FABP3) is a specific biomarker of muscle and heart tissue injury. This protein is purported to be involved in early myocardial development, adult myocardial tissue repair and responsible for the modulation of cell growth and proliferation. We have investigated the role of FABP3 in human bone marrow derived mesenchymal stem cells under ischemic conditions. MSCs from 12 donors were cultured either in standard normoxic or modified hypoxic conditions, and the differential expression of FABP3 was tested by quantitative {sup RT}PCR and western blot. We also established stable FABP3 expression in MSCs and searched for variation in cellular proliferation and differentiation bioprocesses affected by hypoxic conditions. We identified: (1) the FABP3 differential expression pattern in the MSCs under hypoxic conditions; (2) over-expression of FABP3 inhibited the growth and proliferation of the MSCs; however, improved their survival in low oxygen environments; (3) the cell growth factors and positive cell cycle regulation genes, such as PCNA, APC, CCNB1, CCNB2 and CDC6 were all down-regulated; while the key negative cell cycle regulation genes TP53, BRCA1, CASP3 and CDKN1A were significantly up-regulated in the cells with FABP3 overexpression. Our data suggested that FABP3 was up-regulated under hypoxia; also negatively regulated the cell metabolic process and the mitotic cell cycle. Overexpression of FABP3 inhibited cell growth and proliferation via negative regulation of the cell cycle and down-regulation of cell growth factors, but enhances cell survival in hypoxic or ischemic conditions. - Highlights: • FABP3 expression pattern was studied in 12 human hypoxic-MSCs. • FABP3 mRNA and proteins are upregulated in the MSCs under hypoxic conditions.

  2. Baicalin inhibits PDGF-induced proliferation and migration of airway smooth muscle cells

    PubMed Central

    Yang, Guang; Li, Jian-Qiang; Bo, Jian-Ping; Wang, Bei; Tian, Xin-Rui; Liu, Tan-Zhen; Liu, Zhuo-La

    2015-01-01

    Airway smooth muscle (ASM) cell proliferation and migration play important roles in airway remodeling in asthma. In vitro platelet-derived growth factor (PDGF) induced ASM cell proliferation and migration. Baicalin is one of flavonoid extracts from Scutellaria baicalensis, which has an anti-asthma effect. However, little is known about its role in PDGF-induced proliferation and migration in rat ASM (RASM) cells. In this study, we aimed to investigate the effects of baicalin on PDGF-induced RASM cell proliferation and migration. We also identified the signaling pathway by which baicalin influences RASM cell proliferation and migration. In the current study, we demonstrated that baicalin suppressed PDGF-induced RASM cell proliferation, arrested PDGF-induced cell-cycle progression. It also suppressed PDGF-induced RASM cell migration. Furthermore, baicalin suppressed PDGF-induced expression of phosphorylated p38, ERK1/2 and JNK in RASM cells. In summary, our study is the first to show that baicalin pretreatment can significantly inhibit PDGF-induced RASM cell proliferation and migration by suppressing the MAPK signaling pathway, and baicalin may be a useful chemotherapeutic agent for asthma. PMID:26884970

  3. E-cadherin mediates contact inhibition of proliferation through Hippo signaling-pathway components

    PubMed Central

    Kim, Nam-Gyun; Koh, Eunjin; Chen, Xiao; Gumbiner, Barry M.

    2011-01-01

    Contact inhibition of cell growth is essential for embryonic development and maintenance of tissue architecture in adult organisms, and the growth of tumors is characterized by a loss of contact inhibition of proliferation. The recently identified Hippo signaling pathway has been implicated in contact inhibition of proliferation as well as organ size control. The modulation of the phosphorylation and nuclear localization of Yes-associated protein (YAP) by the highly conserved kinase cascade of the Hippo signaling pathway has been intensively studied. However, cell-surface receptors regulating the Hippo signaling pathway in mammals are not well understood. In this study, we show that Hippo signaling pathway components are required for E-cadherin–dependent contact inhibition of proliferation. Knockdown of the Hippo signaling components or overexpression of YAP inhibits the decrease in cell proliferation caused by E-cadherin homophilic binding at the cell surface, independent of other cell–cell interactions. We also demonstrate that the E-cadherin/catenin complex functions as an upstream regulator of the Hippo signaling pathway in mammalian cells. Expression of E-cadherin in MDA-MB-231 cells restores the density-dependent regulation of YAP nuclear exclusion. Knockdown of β-catenin in densely cultured MCF10A cells, which mainly depletes E-cadherin–bound β-catenin, induces a decrease in the phosphorylation of S127 residue of YAP and its nuclear accumulation. Moreover, E-cadherin homophilic binding independent of other cell interactions is sufficient to control the subcellular localization of YAP. Therefore, Our results indicate that, in addition to its role in cell–cell adhesion, E-cadherin-mediated cell–cell contact directly regulates the Hippo signaling pathway to control cell proliferation. PMID:21730131

  4. MicroRNA-490-5p inhibits proliferation of bladder cancer by targeting c-Fos

    SciTech Connect

    Li, Shiqi; Xu, Xianglai; Xu, Xin; Hu, Zhenghui; Wu, Jian; Zhu, Yi; Chen, Hong; Mao, Yeqing; Lin, Yiwei; Luo, Jindan; Zheng, Xiangyi; Xie, Liping

    2013-11-29

    Highlights: •We examined the level of miR-490-5p in bladder cancer tissues and three cancer cell lines. •We are the first to show the function of miR-490-5p in bladder cancer. •We demonstrate c-Fos may be a target of miR-490-5p. -- Abstract: MicroRNAs (miRNAs) are non-protein-coding sequences that play a crucial role in tumorigenesis by negatively regulating gene expression. Here, we found that miR-490-5p is down-regulated in human bladder cancer tissue and cell lines compared to normal adjacent tissue and a non-malignant cell line. To better characterize the function of miR-490-5p in bladder cancer, we over-expressed miR-490-5p in bladder cancer cell lines with chemically synthesized mimics. Enforced expression of miR-490-5p in bladder cancer cells significantly inhibited the cell proliferation via G1-phase arrest. Further studies found the decreased c-Fos expression at both mRNA and protein levels and Luciferase reporter assays demonstrated that c-Fos is a direct target of miR-490-5p in bladder cancer. These findings indicate miR-490-5p to be a novel tumor suppressor of bladder cancer cell proliferation through targeting c-Fos.

  5. Inhibition of CXCR4 and CXCR7 for reduction of cell proliferation and invasion in human endometrial cancer.

    PubMed

    Long, Ping; Sun, Fengyi; Ma, Yingying; Huang, Yu

    2016-06-01

    As one of the most common malignant cancers in female reproductive tract, endometrial cancer accounts for 20-30 % of the most frequent gynecological malignancy, which is originated from endometrial epithelial. The molecular mechanisms for the generation of endometrial cancer are up to now unclear, hindering the development of corresponding therapy. CXCR4 and CXCR7 were receptors of CXCL12 chemokine ligand, which could regulate critical procedures of neoplastic transformation, including proliferation, invasion, and apoptosis of the cells. The messenger RNA (mRNA) and protein expression levels of CXCR4 and CXCR7 in human endometrial adenocarcinoma cancer, as well as in Ishikawa and HEC-1-A cell line, were analyzed by using reverse-transcription polymerase chain reaction (RT-PCR) and Western blotting. In order to explore the biological function of CXCR4 and CXCR7 in endometrial tumor, small interference RNAs of CXCR4 and CXCR7 fragments were designed, synthesized, and transfected into Ishikawa and HEC-1-A by using Lipofectamine2000. The influence of RNA interference (RNAi)-mediated silencing CXCR4 and CXCR7 on the cell proliferation was investigated under CCK-8. The invasion assay was performed transwell, and cell apoptosis was tested by FCM. Higher mRNA and protein expression levels of CXCR4 and CXCR7 were investigated in endometrial adenocarcinomas. The expression levels of CXCR4 and CXCR7 could be inhibited by RNA interference, reducing the cell proliferation, invasion in Ishikawa and HEC-1-A cells. In this study, we also observed that treated with CXCR4 and CXCR7 small interfering RNA (siRNA) arrested cells in S phase. CXCL12/CXCR4 and CXCL12/CXCR7 receptor ligand systems affect the invasion of endometrial carcinoma cell line into Ishikawa and HEC-1-A. CXCR4 and CXCR7 were silenced by RNAi, which can inhibit the invasion of Ishikawa and HEC-1-A cell lines. Hence, CXCR4 and CXCR7 are expected to become two target genes for the treatment of endometrial carcinoma

  6. Inhibition of human copper trafficking by a small molecule significantly attenuates cancer cell proliferation

    PubMed Central

    Wang, Jing; Luo, Cheng; Shan, Changliang; You, Qiancheng; Lu, Junyan; Elf, Shannon; Zhou, Yu; Wen, Yi; Vinkenborg, Jan L.; Fan, Jun; Kang, Heebum; Lin, Ruiting; Han, Dali; Xie, Yuxin; Karpus, Jason; Chen, Shijie; Ouyang, Shisheng; Luan, Chihao; Zhang, Naixia; Ding, Hong; Merkx, Maarten; Liu, Hong; Chen, Jing; Jiang, Hualiang; He, Chuan

    2016-01-01

    Copper is a transition metal that plays critical roles in many life processes. Controlling the cellular concentration and trafficking of copper offers a route to disrupt these processes. Here we report small molecules that inhibit the human copper-trafficking proteins Atox1 and CCS, and so provide a selective approach to disrupt cellular copper transport. The knockdown of Atox1 and CCS or their inhibition leads to a significantly reduced proliferation of cancer cells, but not of normal cells, as well as to attenuated tumour growth in mouse models. We show that blocking copper trafficking induces cellular oxidative stress and reduces levels of cellular ATP. The reduced level of ATP results in activation of the AMP-activated protein kinase that leads to reduced lipogenesis. Both effects contribute to the inhibition of cancer cell proliferation. Our results establish copper chaperones as new targets for future developments in anticancer therapies. PMID:26587712

  7. Inhibition of human copper trafficking by a small molecule significantly attenuates cancer cell proliferation.

    PubMed

    Wang, Jing; Luo, Cheng; Shan, Changliang; You, Qiancheng; Lu, Junyan; Elf, Shannon; Zhou, Yu; Wen, Yi; Vinkenborg, Jan L; Fan, Jun; Kang, Heebum; Lin, Ruiting; Han, Dali; Xie, Yuxin; Karpus, Jason; Chen, Shijie; Ouyang, Shisheng; Luan, Chihao; Zhang, Naixia; Ding, Hong; Merkx, Maarten; Liu, Hong; Chen, Jing; Jiang, Hualiang; He, Chuan

    2015-12-01

    Copper is a transition metal that plays critical roles in many life processes. Controlling the cellular concentration and trafficking of copper offers a route to disrupt these processes. Here we report small molecules that inhibit the human copper-trafficking proteins Atox1 and CCS, and so provide a selective approach to disrupt cellular copper transport. The knockdown of Atox1 and CCS or their inhibition leads to a significantly reduced proliferation of cancer cells, but not of normal cells, as well as to attenuated tumour growth in mouse models. We show that blocking copper trafficking induces cellular oxidative stress and reduces levels of cellular ATP. The reduced level of ATP results in activation of the AMP-activated protein kinase that leads to reduced lipogenesis. Both effects contribute to the inhibition of cancer cell proliferation. Our results establish copper chaperones as new targets for future developments in anticancer therapies. PMID:26587712

  8. Inhibition of human copper trafficking by a small molecule significantly attenuates cancer cell proliferation

    NASA Astrophysics Data System (ADS)

    Wang, Jing; Luo, Cheng; Shan, Changliang; You, Qiancheng; Lu, Junyan; Elf, Shannon; Zhou, Yu; Wen, Yi; Vinkenborg, Jan L.; Fan, Jun; Kang, Heebum; Lin, Ruiting; Han, Dali; Xie, Yuxin; Karpus, Jason; Chen, Shijie; Ouyang, Shisheng; Luan, Chihao; Zhang, Naixia; Ding, Hong; Merkx, Maarten; Liu, Hong; Chen, Jing; Jiang, Hualiang; He, Chuan

    2015-12-01

    Copper is a transition metal that plays critical roles in many life processes. Controlling the cellular concentration and trafficking of copper offers a route to disrupt these processes. Here we report small molecules that inhibit the human copper-trafficking proteins Atox1 and CCS, and so provide a selective approach to disrupt cellular copper transport. The knockdown of Atox1 and CCS or their inhibition leads to a significantly reduced proliferation of cancer cells, but not of normal cells, as well as to attenuated tumour growth in mouse models. We show that blocking copper trafficking induces cellular oxidative stress and reduces levels of cellular ATP. The reduced level of ATP results in activation of the AMP-activated protein kinase that leads to reduced lipogenesis. Both effects contribute to the inhibition of cancer cell proliferation. Our results establish copper chaperones as new targets for future developments in anticancer therapies.

  9. Nickel Ions Selectively Inhibit Lipopolysaccharide-Induced Interleukin-6 Production by Decreasing Its mRNA Stability

    PubMed Central

    Asakawa, Sanki; Kishimoto, Yu; Takano, Takayuki; Okita, Kiyuki; Takakuwa, Shiho; Sato, Taiki; Hiratsuka, Masahiro; Takeuchi, Osamu; Hirasawa, Noriyasu

    2015-01-01

    Nickel (Ni) ions easily elute from many alloys and elicit inflammation and allergies. Previous studies have shown that infections due to the implantation of medical devices cause inflammation and enhance the elution of Ni ions (Ni2+). However, cross-talk between infection- and Ni2+-induced signaling pathways has not yet been elucidated in detail. In the present study, we investigated the effects of Ni2+ on the lipopolysaccharide (LPS)-induced production of cytokines in a LPS-induced air pouch-type inflammation model in BALB/c mice and the murine macrophage cell line RAW264. We demonstrated that Ni2+ inhibited the LPS-induced production of interleukin (IL)-6, but not that of tumor necrosis factor (TNF)-α both in vivo and in vitro. This inhibitory effect was also observed with cobalt ion (Co2+), but not with chloride ion (Cl-), zinc ion (Zn2+), or palladium ion (Pd2+), and was highly selective to the production of IL-6. Ni2+ did not inhibit the activation of ERK1/2, p38 MAPK, or JNK. Although Ni2+ decreased IL-6 mRNA levels, it failed to inhibit the LPS-induced activation of the IL-6 promoter. An experiment using actinomycin D, a transcription inhibitor, revealed that Ni2+ decreased the stability of IL-6 mRNA. Moreover, Ni2+ inhibited the LPS-induced expression of Arid5a, but not regnase-1. These results demonstrated that Ni2+ may have selectively inhibited the LPS-induced production of IL-6 by decreasing the Arid5a-dependent stabilization of IL-6 mRNA. PMID:25742007

  10. Nickel ions selectively inhibit lipopolysaccharide-induced interleukin-6 production by decreasing its mRNA stability.

    PubMed

    Asakawa, Sanki; Kishimoto, Yu; Takano, Takayuki; Okita, Kiyuki; Takakuwa, Shiho; Sato, Taiki; Hiratsuka, Masahiro; Takeuchi, Osamu; Hirasawa, Noriyasu

    2015-01-01

    Nickel (Ni) ions easily elute from many alloys and elicit inflammation and allergies. Previous studies have shown that infections due to the implantation of medical devices cause inflammation and enhance the elution of Ni ions (Ni²⁺). However, cross-talk between infection- and Ni²⁺-induced signaling pathways has not yet been elucidated in detail. In the present study, we investigated the effects of Ni2+ on the lipopolysaccharide (LPS)-induced production of cytokines in a LPS-induced air pouch-type inflammation model in BALB/c mice and the murine macrophage cell line RAW264. We demonstrated that Ni²⁺ inhibited the LPS-induced production of interleukin (IL)-6, but not that of tumor necrosis factor (TNF)-α both in vivo and in vitro. This inhibitory effect was also observed with cobalt ion (Co²⁺), but not with chloride ion (Cl⁻), zinc ion (Zn²⁺), or palladium ion (Pd²⁺), and was highly selective to the production of IL-6. Ni²⁺ did not inhibit the activation of ERK1/2, p38 MAPK, or JNK. Although Ni²⁺ decreased IL-6 mRNA levels, it failed to inhibit the LPS-induced activation of the IL-6 promoter. An experiment using actinomycin D, a transcription inhibitor, revealed that Ni²⁺ decreased the stability of IL-6 mRNA. Moreover, Ni²⁺ inhibited the LPS-induced expression of Arid5a, but not regnase-1. These results demonstrated that Ni²⁺ may have selectively inhibited the LPS-induced production of IL-6 by decreasing the Arid5a-dependent stabilization of IL-6 mRNA. PMID:25742007

  11. Vasoactive Intestinal Peptide Inhibits Human Small-Cell Lung Cancer Proliferation in vitro and in vivo

    NASA Astrophysics Data System (ADS)

    Maruno, Kaname; Absood, Afaf; Said, Sami I.

    1998-11-01

    Small-cell lung carcinoma (SCLC) is an aggressive, rapidly growing and metastasizing, and highly fatal neoplasm. We report that vasoactive intestinal peptide inhibits the proliferation of SCLC cells in culture and dramatically suppresses the growth of SCLC tumor-cell implants in athymic nude mice. In both cases, the inhibition was mediated apparently by a cAMP-dependent mechanism, because the inhibition was enhanced by the adenylate cyclase activator forskolin and the phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine in proportion to increases in intracellular cAMP levels, and the inhibition was abolished by selective inhibition of cAMP-dependent protein kinase. If confirmed in clinical trials, this antiproliferative action of vasoactive intestinal peptide may offer a new and promising means of suppressing SCLC in human subjects, without the toxic side effects of chemotherapeutic agents.

  12. Inhibition of Excessive Cell Proliferation by Calcilytics in Idiopathic Pulmonary Arterial Hypertension

    PubMed Central

    Yamamura, Aya; Ohara, Naoki; Tsukamoto, Kikuo

    2015-01-01

    Idiopathic pulmonary arterial hypertension (IPAH) is a rare and progressive disease of unknown pathogenesis. Vascular remodeling due to excessive proliferation of pulmonary arterial smooth muscle cells (PASMCs) is a critical pathogenic event that leads to early morbidity and mortality. The excessive cell proliferation is closely linked to the augmented Ca2+ signaling in PASMCs. More recently, we have shown by an siRNA knockdown method that the Ca2+-sensing receptor (CaSR) is upregulated in PASMCs from IPAH patients, involved in the enhanced Ca2+ response and subsequent excessive cell proliferation. In this study, we examined whether pharmacological blockade of CaSR attenuated the excessive proliferation of PASMCs from IPAH patients by MTT assay. The proliferation rate of PASMCs from IPAH patients was much higher (~1.5-fold) than that of PASMCs from normal subjects and patients with chronic thromboembolic pulmonary hypertension (CTEPH). Treatment with NPS2143, an antagonist of CaSR or calcilytic, clearly suppressed the cell proliferation in a concentration-dependent manner (IC50 = 2.64 μM) in IPAH-PASMCs, but not in normal and CTEPH PASMCs. Another calcilytic, Calhex 231, which is structurally unrelated to NPS2143, also concentration-dependently inhibited the excessive proliferation of IPAH-PASMCs (IC50 = 1.89 μM). In contrast, R568, an activator of CaSR or calcimimetic, significantly facilitated the proliferation of IPAH-PASMCs (EC50 = 0.33 μM). Similar results were obtained by BrdU incorporation assay. These results reveal that the excessive PASMC proliferation was modulated by pharmacological tools of CaSR, showing us that calcilytics are useful for a novel therapeutic approach for pulmonary arterial hypertension. PMID:26375676

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

    SciTech Connect

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

    2013-01-11

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

  14. N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide, a calmodulin antagonist, inhibits cell proliferation.

    PubMed Central

    Hidaka, H; Sasaki, Y; Tanaka, T; Endo, T; Ohno, S; Fujii, Y; Nagata, T

    1981-01-01

    N-(6-Aminohexyl)-5-chloro-1-naphthalenesulfonamide (W-7) and its derivatives are putative calmodulin antagonists that bind to calmodulin and inhibit Ca2+/calmodulin-regulated enzyme activities. Autoradiographic studies using tritiated W-7 showed that this compound penetrates the cell membrane, is distributed mainly in the cytoplasm, and inhibits proliferation of Chinese hamster ovary K1 (CHO-K1) cells. Cytoplasmic [3H]W-7 was excluded completely within 6 hr after removal of [3H]W-7 from the culture medium. N-(6-aminohexyl)-1-naphthalenesulfonamide, an analogue of W-7 that interacts only weakly with calmodulin, proved to be a much weaker inhibitor of cell proliferation. CHO-K1 cells were synchronized by shaking during mitosis and then released into the cell cycle in the presence of 25 microM W-7 or 2.5 mM thymidine for 12 hr. Cell division was observed approximately 6 hr later. The results suggest that the effect of W-7 on cell proliferation might be through selective inhibition of the G1/S boundary phase, which is similar to the effect of excess thymidine. This pharmacological demonstration that cytoplasmic calmodulin is involved in cell proliferation is significant; W-7 and its derivatives may be useful tools for research on calmodulin and cell biology-related studies. Images PMID:6945588

  15. Shikonin Inhibits the Proliferation of Human Breast Cancer Cells by Reducing Tumor-Derived Exosomes.

    PubMed

    Wei, Yao; Li, Mingzhen; Cui, Shufang; Wang, Dong; Zhang, Chen-Yu; Zen, Ke; Li, Limin

    2016-01-01

    Shikonin is a naphthoquinone isolated from the traditional Chinese medicine Lithospermum. It has been used in the treatment of various tumors. However, the effects of shikonin on such diseases have not been fully elucidated. In the present study, we detected the exosome release of a breast cancer cell line (MCF-7) with shikonin treatment and found a positive relationship between the level of secreted exosomes and cell proliferation. We next analyzed miRNA profiles in MCF-7 cells and exosomes and found that some miRNAs are specifically sorted and abundant in exosomes. Knockdown of the most abundant miRNAs in exosomes and the MCF-7 proliferation assay showed that miR-128 in exosomes negatively regulates the level of Bax in MCF-7 recipient cells and inhibits cell proliferation. These results show that shikonin inhibits the proliferation of MCF-7 cells through reducing tumor-derived exosomal miR-128. The current study suggests that shikonin suppresses MCF-7 growth by the inhibition of exosome release. PMID:27322220

  16. Troglitazone inhibits endothelial cell proliferation through suppression of casein kinase 2 activity

    SciTech Connect

    Lee, Kuy-Sook; Park, Jin-Hee; Lee, Seahyoung; Lim, Hyun-Joung; Jang, Yangsoo; Park, Hyun-Young . E-mail: hypark65@nih.go.kr

    2006-07-21

    Troglitazone, an agonist of peroxisome proliferator activated receptor{gamma} (PPAR{gamma}), has been reported to inhibit endothelial cell proliferation by suppressing Akt activation. Recently, it has been also proposed that phosphatase and tensin homolog deleted from chromosome 10 (PTEN) plays an important role in such effect of troglitazone. However, the mechanism of how troglitazone regulates PTEN remains to be elucidated. We therefore investigated the effects of troglitazone on casein kinase 2 (CK2), which is known to negatively regulate PTEN activity. Troglitazone significantly inhibited serum-induced proliferation of HUVEC in a concentration dependent manner. Serum-induced Akt and its downstream signaling pathway activation was attenuated by troglitazone (10 {mu}M) pretreatment. The phosphorylation of PTEN, which was directly related to Akt activation, was decreased with troglitazone pretreatment and was inversely proportional to CK2 activity. DRB, a CK2 inhibitor, also showed effects similar to that of troglitazone on Akt and its downstream signaling molecules. In conclusion, our results suggest that troglitazone inhibits proliferation of HUVECs through suppression of CK2 activity rendering PTEN to remain activated, and this effect of troglitazone in HUVECs seems to be PPAR{gamma} independent.

  17. WNT3 Inhibits Cerebellar Granule Neuron Progenitor Proliferation and Medulloblastoma Formation via MAPK Activation

    PubMed Central

    Ayrault, Olivier; Kim, Jee Hae; Zhu, Xiaodong; Murphy, David A.; Van Aelst, Linda; Roussel, Martine F.; Hatten, Mary E.

    2013-01-01

    During normal cerebellar development, the remarkable expansion of granule cell progenitors (GCPs) generates a population of granule neurons that outnumbers the total neuronal population of the cerebral cortex, and provides a model for identifying signaling pathways that may be defective in medulloblastoma. While many studies focus on identifying pathways that promote growth of GCPs, a critical unanswered question concerns the identification of signaling pathways that block mitogenic stimulation and induce early steps in differentiation. Here we identify WNT3 as a novel suppressor of GCP proliferation during cerebellar development and an inhibitor of medulloblastoma growth in mice. WNT3, produced in early postnatal cerebellum, inhibits GCP proliferation by down-regulating pro-proliferative target genes of the mitogen Sonic Hedgehog (SHH) and the bHLH transcription factor Atoh1. WNT3 suppresses GCP growth through a non-canonical Wnt signaling pathway, activating prototypic mitogen-activated protein kinases (MAPKs), the Ras-dependent extracellular-signal-regulated kinases 1/2 (ERK1/2) and ERK5, instead of the classical β-catenin pathway. Inhibition of MAPK activity using a MAPK kinase (MEK) inhibitor reversed the inhibitory effect of WNT3 on GCP proliferation. Importantly, WNT3 inhibits proliferation of medulloblastoma tumor growth in mouse models by a similar mechanism. Thus, the present study suggests a novel role for WNT3 as a regulator of neurogenesis and repressor of neural tumors. PMID:24303070

  18. Knockdown of Golgi phosphoprotein 2 inhibits hepatocellular carcinoma cell proliferation and motility

    PubMed Central

    Liu, Yiming; Zhang, Xiaodi; Sun, Ting; Jiang, Junchang; Li, Ying; Chen, Mingliang; Wei, Zhen; Jiang, Weiqin; Zhou, Linfu

    2016-01-01

    Golgi phosphoprotein 2 (GP73) is highly expressed in hepatocellular carcinoma (HCC) cells, where it serves as a biomarker and indicator of disease progression. We used MTS assays, anchorage-independent cell colony formation assays and a xenograft tumor model to show that GP73-specific siRNAs inhibit HCC proliferation in HepG2, SMMC-7721, and Huh7 cell lines and in vivo. Following GP73 silencing, levels of p-Rb, a factor related to metastasis, were reduced, but cell cycle progression was unaffected. Our results suggest that GP73 silencing may not directly suppress proliferation, but may instead inhibit cell motility. Results from proliferation assays suggest GP73 reduces expression of epithelial mesenchymal transition (EMT)-related factors and promotes cell motility, while transwell migration and invasion assays indicated a possible role in metastasis. Immunofluorescence co-localization microscopy and immunoblotting showed that GP73 decreases expression of N-cadherin and E-cadherin, two key factors in EMT, which may in turn decrease intracellular adhesive forces and promote cell motility. This study confirmed that GP73 expression leads to increased expression of EMT-related proteins and that GP73 silencing reduces HCC cell migration in vitro. These findings suggest that GP73 silencing through siRNA delivery may provide a novel low-toxicity therapy for the inhibition of tumor proliferation and metastasis. PMID:26870893

  19. Serine leucocyte proteinase inhibitor-treated monocyte inhibits human CD4(+) lymphocyte proliferation.

    PubMed

    Guerrieri, Diego; Tateosian, Nancy L; Maffía, Paulo C; Reiteri, Romina M; Amiano, Nicolás O; Costa, María J; Villalonga, Ximena; Sanchez, Mercedes L; Estein, Silvia M; Garcia, Verónica E; Sallenave, Jean-Michel; Chuluyan, Héctor E

    2011-08-01

    Serine leucocyte proteinase inhibitor (SLPI) is the main serine proteinase inhibitor produced by epithelial cells and has been shown to be a pleiotropic molecule with anti-inflammatory and microbicidal activities. However, the role of SLPI on the adaptive immune response is not well established. Therefore, we evaluated the effect of SLPI on lymphocyte proliferation and cytokine production. Human peripheral blood mononuclear cells (PBMC) were treated with mitogens plus SLPI and proliferation was assessed by [(3) H]thymidine uptake. The SLPI decreased the lymphocyte proliferation induced by interleukin-2 (IL-2) or OKT3 monoclonal antibodies in a dose-dependent manner. Inhibition was not observed when depleting monocytes from the PBMC and it was restored by adding monocytes and SLPI. SLPI-treated monocyte slightly decreased MHC II and increased CD18 expression, and secreted greater amounts of IL-4, IL-6 and IL-10 in the cell culture supernatants. SLPI-treated monocyte culture supernatant inhibited the CD4(+) lymphocyte proliferation but did not affect the proliferation of CD8(+) cells. Moreover, IL-2 increased T-bet expression and the presence of SLPI significantly decreased it. Finally, SLPI-treated monocyte culture supernatant dramatically decreased interferon-γ but increased IL-4, IL-6 and IL-10 in the presence of IL-2-treated T cells. Our results demonstrate that SLPI target monocytes, which in turn inhibit CD4 lymphocyte proliferation and T helper type 1 cytokine secretion. Overall, these results suggest that SLPI is an alarm protein that modulates not only the innate immune response but also the adaptive immune response. PMID:21574992

  20. Serine leucocyte proteinase inhibitor-treated monocyte inhibits human CD4+ lymphocyte proliferation

    PubMed Central

    Guerrieri, Diego; Tateosian, Nancy L; Maffía, Paulo C; Reiteri, Romina M; Amiano, Nicolás O; Costa, María J; Villalonga, Ximena; Sanchez, Mercedes L; Estein, Silvia M; Garcia, Verónica E; Sallenave, Jean-Michel; Chuluyan, Héctor E

    2011-01-01

    Serine leucocyte proteinase inhibitor (SLPI) is the main serine proteinase inhibitor produced by epithelial cells and has been shown to be a pleiotropic molecule with anti-inflammatory and microbicidal activities. However, the role of SLPI on the adaptive immune response is not well established. Therefore, we evaluated the effect of SLPI on lymphocyte proliferation and cytokine production. Human peripheral blood mononuclear cells (PBMC) were treated with mitogens plus SLPI and proliferation was assessed by [3H]thymidine uptake. The SLPI decreased the lymphocyte proliferation induced by interleukin-2 (IL-2) or OKT3 monoclonal antibodies in a dose-dependent manner. Inhibition was not observed when depleting monocytes from the PBMC and it was restored by adding monocytes and SLPI. SLPI-treated monocyte slightly decreased MHC II and increased CD18 expression, and secreted greater amounts of IL-4, IL-6 and IL-10 in the cell culture supernatants. SLPI-treated monocyte culture supernatant inhibited the CD4+ lymphocyte proliferation but did not affect the proliferation of CD8+ cells. Moreover, IL-2 increased T-bet expression and the presence of SLPI significantly decreased it. Finally, SLPI-treated monocyte culture supernatant dramatically decreased interferon-γ but increased IL-4, IL-6 and IL-10 in the presence of IL-2-treated T cells. Our results demonstrate that SLPI target monocytes, which in turn inhibit CD4 lymphocyte proliferation and T helper type 1 cytokine secretion. Overall, these results suggest that SLPI is an alarm protein that modulates not only the innate immune response but also the adaptive immune response. PMID:21574992

  1. TGF-{beta}2 inhibits AKT activation and FGF-2-induced corneal endothelial cell proliferation

    SciTech Connect

    Lu Jiawei; Lu Zhenyu; Reinach, Peter

    2006-11-01

    The corneal endothelial cells form a boundary layer between anterior chamber and cornea. This single cell layer is important to maintain cornea transparency by eliciting net fluid transport into the anterior chamber. Injuries of the corneal endothelial layer in humans lead to corneal swelling and translucence. This hindrance is thought to be due to limited proliferative capacity of the endothelial layer. Fibroblast growth factor 2 (FGF-2) and transforming growth factor-beta 2 (TGF-{beta}2) are both found in aqueous humor, and these two cytokines promote and inhibit cell growth, respectively. The intracellular signaling mechanisms by which TGF-{beta}2 suppresses the mitogenic response to FGF-2, however, remain unclear. We have addressed this question by investigating potential crosstalk between FGF-2-induced and TGF-{beta}2-regulated intracellular signaling events in cultured bovine corneal endothelial (BCE) cells. We found that TGF-{beta}2 and FGF-2 oppositely affect BCE cell proliferation and TGF-{beta}2 can override the stimulating effects of FGF-2 by increasing COX-2 expression in these cells. Consistent with these findings, overexpression of COX-2 significantly reduced FGF-2-induced cell proliferation whereas a COX-2 specific inhibitor NS398 reversed the effect of TGF-{beta}2 on FGF-2-induced cell proliferation. The COX-2 product prostaglandin E2 (PGE-2) blocks FGF-2-induced cell proliferation. Whereas FGF-2 stimulates cell proliferation by activating the AKT pathway, TGF-{beta}2 and PGE-2 both inhibit this pathway. In accordance with the effect of PGE-2, cAMP also inhibits FGF-2-induced AKT activation. These findings suggest that the mitogenic response to FGF-2 in vivo in the corneal endothelial layer may be inhibited by TGF-{beta}2-induced suppression of the PI3-kinase/AKT signaling pathway.

  2. MiR-506 Over-Expression Inhibits Proliferation and Metastasis of Breast Cancer Cells

    PubMed Central

    Yu, Fei; Lv, Mingli; Li, Dan; Cai, Haidong; Ma, Lishui; Luo, Qiong; Yuan, Xueyu; Lv, Zhongwei

    2015-01-01

    Background This study aimed to investigate the relationship between miR-506 and proliferation and migration of breast cancer cells. Material/Methods MiR-506 mimics, inhibitor, and negative control (NC) were transfected into MDA-MB-231 breast cancer cells. Cell proliferation, cell counting, colony formation assay, and Transwell assay were applied to evaluate the proliferation and migration of breast cancer cells. Data are shown as mean ± standard deviation and the experiment was performed 3 times. Statistical analyses were performed with SPSS version 10.0. Results At 1 day after transfection, cell proliferation detected by CCK-8 assay was significantly promoted in miR-506 inhibitor when compared with the miR-506 mimics group and the NC group (P<0.05). At 3 days or 5 days after transfection, cell proliferation was markedly inhibited in the miR-506 mimics group, and miR-506 inhibitor was still significantly promoted. Cell counting with a hemocytometer showed similar results to cell proliferation. Colony formation assay showed that the number of colonies in the miR-506 mimics group was significantly smaller than that in the miR-506 inhibitor group and NC group. Transwell assay revealed that the number of migrated cells in miR-506 mimics was markedly smaller than that in the miR-506 inhibitor group and NC group. Conclusions MiR-506 over-expression significantly inhibits the proliferation, colony formation, and migration of breast cancer cells. miR-506 over-expression may thus be able to improve the malignant phenotype of breast cancer cells. PMID:26059632

  3. Synergistic Effect of Functionalized Nickel Nanoparticles and Quercetin on Inhibition of the SMMC-7721 Cells Proliferation

    NASA Astrophysics Data System (ADS)

    Guo, Dadong; Wu, Chunhui; Li, Jingyuan; Guo, Airong; Li, Qingning; Jiang, Hui; Chen, Baoan; Wang, Xuemei

    2009-12-01

    The effect of functionalized nickel (Ni) nanoparticles capped with positively charged tetraheptylammonium on cellular uptake of drug quercetin into hepatocellular carcinoma cells (SMMC-7721) has been explored in this study via microscopy and electrochemical characterization as well as MTT assay. Meanwhile, the influence of Ni nanoparticles and/or quercetin on cell proliferation has been further evaluated by the real-time cell electronic sensing (RT-CES) study. Our observations indicate that Ni nanoparticles could efficiently improve the permeability of cancer cell membrane, and remarkably enhance the accumulation of quercetin in SMMC-7721 cells, suggesting that Ni nanoparticles and quercetin would facilitate the synergistic effect on inhibiting proliferation of cancer cells.

  4. Novel roles of TMEM100: inhibition metastasis and proliferation of hepatocellular carcinoma

    PubMed Central

    Hua, Dong; Xiao, Shuai; Yang, Lianyue

    2015-01-01

    Transmembrane protein 100 (TMEM100) was activated by ALK1/TGF-β signaling. We found that TMEM100 was decreased in hepatocellular carcinoma (HCC) tissues and in highly metastatic cell lines. Overexpressed of TMEM100 inhibited invasion, migration and proliferation. Low levels of TMEM100 were associated with cirrhosis, tumor size, Tumor nodule number, TNM stage, BCLC stage, Edmondson-Steiner Stage and vein invasion. Furthermore, TMEM100 was an independent risk factor for overall survival (P = 0.03) and disease-free survival (P = 0.019). The current findings suggest that TMEM100 functions as a tumor suppressor in HCC metastasis and proliferation. PMID:25978032

  5. Imatinib mesylate (Gleevec) downregulates telomerase activity and inhibits proliferation in telomerase-expressing cell lines

    PubMed Central

    Uziel, O; Fenig, E; Nordenberg, J; Beery, E; Reshef, H; Sandbank, J; Birenbaum, M; Bakhanashvili, M; Yerushalmi, R; Luria, D; Lahav, M

    2005-01-01

    Imatinib mesylate (IM) is a tyrosine kinase inhibitor, which inhibits phosphorylation of downstream proteins involved in BCR-ABL signal transduction. It has proved beneficial in treating patients with chronic myeloid leukaemia (CML). In addition, IM demonstrates activity against malignant cells expressing c-kit and platelet-derived growth factor receptor (PDGF-R). The activity of IM in the blastic crisis of CML and against various myeloma cell lines suggests that this drug may also target other cellular components. In the light of the important role of telomerase in malignant transformation, we evaluated the effect of IM on telomerase activity (TA) and regulation in various malignant cell lines. Imatinib mesylate caused a dose-dependent inhibition of TA (up to 90% at a concentration of 15 μM IM) in c-kit-expressing SK-N-MC (Ewing sarcoma), SK-MEL-28 (melanoma), RPMI 8226 (myeloma), MCF-7 (breast cancer) and HSC 536/N (Fanconi anaemia) cells as well as in ba/F3 (murine pro-B cells), which do not express c-kit, BCR-ABL or PDGF-R. Imatinib mesylate did not affect the activity of other DNA polymerases. Inhibition of TA was associated with 50% inhibition of proliferation. The inhibition of proliferation was associated with a decrease in the S-phase of the cell cycle and an accumulation of cells in the G2/M phase. No apoptosis was observed. Inhibition of TA was caused mainly by post-translational modifications: dephosphorylation of AKT and, to a smaller extent, by early downregulation of hTERT (the catalytic subunit of the enzyme) transcription. Other steps of telomerase regulation were not affected by IM. This study demonstrates an additional cellular target of IM, not necessarily mediated via known tyrosine kinases, that causes inhibition of TA and cell proliferation. PMID:15870711

  6. Phenylboronic acid-functionalized polyamidoamine-mediated Bcl-2 siRNA delivery for inhibiting the cell proliferation.

    PubMed

    Wu, Di; Yang, Jiebing; Xing, Zhen; Han, Haobo; Wang, Tingting; Zhang, Aijun; Yang, Yan; Li, Quanshun

    2016-10-01

    In this study, the conjugation of phenylboronic acid (PBA) to amine-terminated polyamidoamine (PAMAM) was successfully conducted to prepare a tumor-targeted gene carrier PBA-functionalized PAMAM (PPP) for Bcl-2 siRNA delivery, using a heterobifunctional crosslinker NHS-PEG5k-Mal. The carrier possessed favorable capacity for siRNA condensation and could protect siRNA from the degradation against RNase and serum. The introduction of PBA could facilitate the cellular uptake and further transfection of Bcl-2 siRNA demonstrated by confocal laser scanning microscopy and flow cytometry. Meanwhile, PPP-mediated transfection of Bcl-2 siRNA could significantly inhibit the expression of Bcl-2 gene at both mRNA and protein levels. Furthermore, owing to the knock-down of Bcl-2, PPP/siRNA could significantly inhibit the cell proliferation by inducing the cell apoptosis, and also enhance the antitumor efficiency of doxorubicin by suppressing the resistance of tumor cells to chemotherapeutics. In conclusion, the PPP-mediated Bcl-2 siRNA delivery could potentially be an effective platform for solving the drug resistance and further achieving the combined chemotherapy and gene therapy in tumor treatment. PMID:27371891

  7. Oridonin upregulates PTEN through activating p38 MAPK and inhibits proliferation in human colon cancer cells.

    PubMed

    Wu, Qiu-Xiang; Yuan, Shuang-Xue; Ren, Chun-Mei; Yu, Yu; Sun, Wen-Juan; He, Bai-Cheng; Wu, Ke

    2016-06-01

    Oridonin (ORI) has been reported as an antiproliferation and apoptosis-inducing natural product in various cancer cells. However, the exact molecular mechanism underlying these effects remains unclear. In the present study, we demonstrated the antiproliferation effect of ORI in HCT116 cells, and analyzed the possible molecular mechanism which mediates this effect. We found that ORI inhibits proliferation, induces cell cycle arrest and apoptosis in HCT116 cells, thus also tumor growth. Mechanically, we found that ORI has no substantial effect on mRNA expression of phosphatase and tensin homologue (PTEN), but increases the total protein level of PTEN and markedly reduces the phosphorylation of PTEN; Exogenous expression of PTEN potentiates the anticancer effect of ORI, while knockdown of PTEN attenuates it. ORI also increases the phosphorylation of p38 MAPK, and p38 MAPK-specific inhibitor reduces the antiproliferation effect ORI in HCT116 cells. Moreover, inhibition of p38 MAPK increases the phosphorylation of PTEN, and reverses ORI-induced decrease of PTEN phosphorylation. Our findings suggested that ORI may be a potential anticancer drug for colon cancer, this effect may be mediated by enhancing the function of PTEN through reducing its phosphorylation, which may be resulted from the ORI-induced activation of p38 MAPK. PMID:27108927

  8. Methylthioadenosine (MTA) inhibits melanoma cell proliferation and in vivo tumor growth

    PubMed Central

    2010-01-01

    Background Melanoma is the most deadly form of skin cancer without effective treatment. Methylthioadenosine (MTA) is a naturally occurring nucleoside with differential effects on normal and transformed cells. MTA has been widely demonstrated to promote anti-proliferative and pro-apoptotic responses in different cell types. In this study we have assessed the therapeutic potential of MTA in melanoma treatment. Methods To investigate the therapeutic potential of MTA we performed in vitro proliferation and viability assays using six different mouse and human melanoma cell lines wild type for RAS and BRAF or harboring different mutations in RAS pathway. We also have tested its therapeutic capabilities in vivo in a xenograft mouse melanoma model and using variety of molecular techniques and tissue culture we investigated its anti-proliferative and pro-apoptotic properties. Results In vitro experiments showed that MTA treatment inhibited melanoma cell proliferation and viability in a dose dependent manner, where BRAF mutant melanoma cell lines appear to be more sensitive. Importantly, MTA was effective inhibiting in vivo tumor growth. The molecular analysis of tumor samples and in vitro experiments indicated that MTA induces cytostatic rather than pro-apoptotic effects inhibiting the phosphorylation of Akt and S6 ribosomal protein and inducing the down-regulation of cyclin D1. Conclusions MTA inhibits melanoma cell proliferation and in vivo tumor growth particularly in BRAF mutant melanoma cells. These data reveal a naturally occurring drug potentially useful for melanoma treatment. PMID:20529342

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

    SciTech Connect

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

    2010-01-01

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

  10. Induction of sister chromatid exchanges and inhibition of cellular proliferation in vitro. I. Caffeine

    SciTech Connect

    Guglielmi, G.E.; Vogt, T.F.; Tice, R.R.

    1982-01-01

    While many agents have been examined for their ability to induce SCE's, complete dose-response information has often been lacking. We have reexamined the ability of one such compound - caffeine - to induce SCEs and also to inhibit cellular proliferation in human peripheral lymphocytes in vitro. An acute exposure to caffeine prior to the DNA synthetic period did not affect either SCE frequency or the rate of cellular proliferation. Chronic exposure to caffeine throughout the culture period lead to both a dose-dependent increase in SCEs (SCE/sub d/ or doubling dose = 2.4 mM; SCE/sub 10/ or the dose capable of inducing 10 SCE = 1.4 mM) and a dose-dependent inhibition of cellular proliferation (IC/sub 50/ or the 50% inhibition concentration = 2.6 mM). The relative proportion of first generation metaphase cells, an assessment of proliferative inhibiton, increased linearly with increasing caffeine concentrations. However, SCE frequency increased nonlinearly over the same range of caffeine concentrations. Examination of the ratio of nonsymmetrical to symmetrical SCEs in third generation metaphase cells indicated that caffeine induced SCEs in equal frequency in each of three successive generations. The dependency of SCE induction and cellular proliferative inhibition on caffeine's presence during the DNA synthetic period suggests that caffeine may act as an antimetabolite in normal human cells.

  11. Griffipavixanthone, a dimeric xanthone extracted from edible plants, inhibits tumor metastasis and proliferation via downregulation of the RAF pathway in esophageal cancer.

    PubMed

    Ding, Zhijie; Lao, Yuanzhi; Zhang, Hong; Fu, Wenwei; Zhu, Lunlun; Tan, Hongsheng; Xu, Hongxi

    2016-01-12

    Metastasis causes a large number of deaths among esophageal cancer patients. The activation of RAF family proteins elevates tumor metastasis and proliferation. In screen targeting the RAF protein, we identified that Griffipavixanthone (GPX), a dimeric xanthone isolated from Garcinia esculenta, is a B-RAF and C-RAF inhibitor against esophageal cancer cells. Using wound healing, transwell migration and matrigel invasion assays, we confirmed that GPX significantly inhibited cell migration and invasion. Furthermore, exposure to GPX rendered cell proliferation and induced G2/M cell cycle arrest. Our mechanistic study showed that GPX suppressed cancer metastasis and proliferation through downregulation of RAF-MEK-ERK cascades proteins as well as RAF mRNA levels. In a pulmonary metastasis model, the intraperitoneal injection of GPX significantly suppressed esophageal tumor metastasis and ERK protein level in vivo. In conclusion, our present study suggested that GPX could inhibit tumor migration, invasion and proliferation in vitro and in vivo, which indicated the potential of GPX for preventing and treating esophageal cancer. PMID:26646323

  12. Griffipavixanthone, a dimeric xanthone extracted from edible plants, inhibits tumor metastasis and proliferation via downregulation of the RAF pathway in esophageal cancer

    PubMed Central

    Zhang, Hong; Fu, Wenwei; Zhu, Lunlun; Tan, Hongsheng; Xu, Hongxi

    2016-01-01

    Metastasis causes a large number of deaths among esophageal cancer patients. The activation of RAF family proteins elevates tumor metastasis and proliferation. In screen targeting the RAF protein, we identified that Griffipavixanthone (GPX), a dimeric xanthone isolated from Garcinia esculenta, is a B-RAF and C-RAF inhibitor against esophageal cancer cells. Using wound healing, transwell migration and matrigel invasion assays, we confirmed that GPX significantly inhibited cell migration and invasion. Furthermore, exposure to GPX rendered cell proliferation and induced G2/M cell cycle arrest. Our mechanistic study showed that GPX suppressed cancer metastasis and proliferation through downregulation of RAF-MEK-ERK cascades proteins as well as RAF mRNA levels. In a pulmonary metastasis model, the intraperitoneal injection of GPX significantly suppressed esophageal tumor metastasis and ERK protein level in vivo. In conclusion, our present study suggested that GPX could inhibit tumor migration, invasion and proliferation in vitro and in vivo, which indicated the potential of GPX for preventing and treating esophageal cancer. PMID:26646323

  13. Inhibition of DYRK1A Stimulates Human β-Cell Proliferation.

    PubMed

    Dirice, Ercument; Walpita, Deepika; Vetere, Amedeo; Meier, Bennett C; Kahraman, Sevim; Hu, Jiang; Dančík, Vlado; Burns, Sean M; Gilbert, Tamara J; Olson, David E; Clemons, Paul A; Kulkarni, Rohit N; Wagner, Bridget K

    2016-06-01

    Restoring functional β-cell mass is an important therapeutic goal for both type 1 and type 2 diabetes (1). While proliferation of existing β-cells is the primary means of β-cell replacement in rodents (2), it is unclear whether a similar principle applies to humans, as human β-cells are remarkably resistant to stimulation of division (3,4). Here, we show that 5-iodotubercidin (5-IT), an annotated adenosine kinase inhibitor previously reported to increase proliferation in rodent and porcine islets (5), strongly and selectively increases human β-cell proliferation in vitro and in vivo. Remarkably, 5-IT also increased glucose-dependent insulin secretion after prolonged treatment. Kinome profiling revealed 5-IT to be a potent and selective inhibitor of the dual-specificity tyrosine phosphorylation-regulated kinase (DYRK) and cell division cycle-like kinase families. Induction of β-cell proliferation by either 5-IT or harmine, another natural product DYRK1A inhibitor, was suppressed by coincubation with the calcineurin inhibitor FK506, suggesting involvement of DYRK1A and nuclear factor of activated T cells signaling. Gene expression profiling in whole islets treated with 5-IT revealed induction of proliferation- and cell cycle-related genes, suggesting that true proliferation is induced by 5-IT. Furthermore, 5-IT promotes β-cell proliferation in human islets grafted under the kidney capsule of NOD-scid IL2Rg(null) mice. These results point to inhibition of DYRK1A as a therapeutic strategy to increase human β-cell proliferation. PMID:26953159

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

    SciTech Connect

    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

    2013-01-11

    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

  15. Peroxisome Proliferator Activated Receptors Alpha, Beta, and Gamma mRNA and protein expression in human fetal tissues

    EPA Science Inventory

    Peroxisome proliferator-activated receptors (PPARs) regulate lipid and glucose homeostasis, are targets of pharmaceuticals, and are also activated by environmental contaminants. Almost nothing is known about expression of PPARs during human fetal development. This study examine...

  16. Suppression of Akt1 phosphorylation by adenoviral transfer of the PTEN gene inhibits hypoxia-induced proliferation of rat pulmonary arterial smooth muscle cells

    SciTech Connect

    Luo, Chunxia; Yi, Bin; Bai, Li; Xia, Yongzhi; Wang, Guansong; Qian, Guisheng; Feng, Hua

    2010-07-02

    Recent findings identify the role of proliferation of pulmonary artery smooth muscle cells (PASMCs) in pulmonary vascular remodeling. Phosphoinositide 3 kinase (PI3K) and serine/threonine kinase (Akt) proteins are expressed in vascular smooth muscle cells. In addition, phosphatase and tensin homolog deleted on chromosome 10 (PTEN) has been identified as a negative regulator of cytokine signaling that inhibits the PI3K-Akt pathway. However, little is known about the role of PTEN/Akt signaling in hypoxia-associated vascular remodeling. In this study, we found that hypoxia-induced the expression of Akt1 mRNA and phosphorylated protein by at least twofold in rat PASMCs. Phospho-PTEN significantly decreased in the nuclei of PASMCs after hypoxic stimulation. After forcing over-expression of PTEN by adenovirus-mediated PTEN (Ad-PTEN) transfection, the expression of phospho-Akt1 was significantly suppressed in PASMCs at all time-points measured. Additionally, we showed here that hypoxia increased proliferation of PASMCs by nearly twofold and over-expression of PTEN significantly inhibited hypoxia-induced PASMCs proliferation. These findings suggest that phospho-PTEN loss in the nuclei of PASMCs under hypoxic conditions may be the major cause of aberrant activation of Akt1 and may, therefore, play an important role in hypoxia-associated pulmonary arterial remodeling. Finally, the fact that transfection with Ad-PTEN inhibits the phosphorylation of Akt1 in PASMCs suggests a potential therapeutic effect on hypoxia-associated pulmonary arterial remodeling.

  17. CCRK depletion inhibits glioblastoma cell proliferation in a cilium-dependent manner

    PubMed Central

    Yang, Ying; Roine, Niina; Mäkelä, Tomi P

    2013-01-01

    Loss of primary cilia is frequently observed in tumour cells, including glioblastoma cells, and proposed to benefit tumour growth, but a causal link has not been established. Here, we show that CCRK (cell cycle-related kinase) and its substrate ICK (intestinal cell kinase) inhibit ciliogenesis. Depletion of CCRK leads to accumulation of ICK at ciliary tips, altered ciliary transport and inhibition of cell cycle re-entry in NIH3T3 fibroblasts. In glioblastoma cells with deregulated high levels of CCRK, its depletion restores cilia through ICK and an ICK-related kinase MAK, thereby inhibiting glioblastoma cell proliferation. These results indicate that inhibition of ciliogenesis might be a mechanism used by cancer cells to provide a growth advantage. PMID:23743448

  18. Apigenin inhibits pancreatic cancer cell proliferation through G2/M cell cycle arrest

    PubMed Central

    Ujiki, Michael B; Ding, Xian-Zhong; Salabat, M Reza; Bentrem, David J; Golkar, Laleh; Milam, Ben; Talamonti, Mark S; Bell, Richard H; Iwamura, Takeshi; Adrian, Thomas E

    2006-01-01

    Background Many chemotherapeutic agents have been used to treat pancreatic cancer without success. Apigenin, a naturally occurring flavonoid, has been shown to inhibit growth in some cancer cell lines but has not been studied in pancreatic cancer. We hypothesized that apigenin would inhibit pancreatic cancer cell growth in vitro. Results Apigenin caused both time- and concentration-dependent inhibition of DNA synthesis and cell proliferation in four pancreatic cancer cell lines. Apigenin induced G2/M phase cell cycle arrest. Apigenin reduced levels of cyclin A, cyclin B, phosphorylated forms of cdc2 and cdc25, which are all proteins required for G2/M transition. Conclusion Apigenin inhibits growth of pancreatic cancer cells through suppression of cyclin B-associated cdc2 activity and G2/M arrest, and may be a valuable drug for the treatment or prevention of pancreatic cancer. PMID:17196098

  19. Carnosine inhibits KRAS-mediated HCT116 proliferation by affecting ATP and ROS production.

    PubMed

    Iovine, Barbara; Iannella, Maria Luigia; Nocella, Francesca; Pricolo, Maria Rosaria; Bevilacqua, Maria Assunta

    2012-02-28

    Carnosine is a natural dipeptide that has generated particular interest for its antioxidant, anti-aging and especially for its antiproliferative properties. In this study, we demonstrate that carnosine inhibits the proliferation of human HCT116 colon cancer cells. In this cell line, the activating KRAS mutation induces mitochondrial ROS, the signaling molecules for cell proliferation. We observed that 50-100 mM carnosine decreases ATP and ROS concentration and induces cell cycle arrest in G1 phase. In HCT116 cells these effects are related to decreased ERK1/2 phosphorylation and increased p21waf1 protein. Our findings support the concept that carnosine could inhibit HCT116 cell growth via its antioxidant activity and its ability to affect glycolysis. PMID:22137144

  20. Silencing of carboxypeptidase E inhibits cell proliferation, tumorigenicity, and metastasis of osteosarcoma cells

    PubMed Central

    Fan, Shuli; Li, Xu; Li, Leiming; Wang, Liguo; Du, Zhangzhen; Yang, Yan; Zhao, Jiansong; Li, Yan

    2016-01-01

    Carboxypeptidase E (CPE), a prohormone processing enzyme, has been implicated in the progression of multiple malignancies. However, the biological role and molecular mechanisms of CPE in osteosarcoma remain elusive. In this study, we assessed the effects of CPE on cell proliferation, tumorigenicity, migration, and invasion in osteosarcoma. Our results showed that silencing of CPE significantly inhibited cell proliferation, caused cell cycle arrest at G0/G1 phase, decreased the expression levels of cell cycle protein, cyclin D1, and inhibited tumorigenicity in vivo. Additionally, CPE downregulation repressed the migratory and invasive capacities of osteosarcoma cells in vitro. Furthermore, overexpression of CPE-ΔN (a splice variant of CPE) enhanced the cell growth, migration, and invasion of osteosarcoma cells. It is possible that both CPE forms are involved in the tumorigenesis and development of osteosarcoma, and therefore CPE may provide a promising biological target for osteosarcoma therapy. PMID:27274275

  1. Inhibition of Dopamine Receptor D4 Impedes Autophagic Flux, Proliferation, and Survival of Glioblastoma Stem Cells.

    PubMed

    Dolma, Sonam; Selvadurai, Hayden J; Lan, Xiaoyang; Lee, Lilian; Kushida, Michelle; Voisin, Veronique; Whetstone, Heather; So, Milly; Aviv, Tzvi; Park, Nicole; Zhu, Xueming; Xu, ChangJiang; Head, Renee; Rowland, Katherine J; Bernstein, Mark; Clarke, Ian D; Bader, Gary; Harrington, Lea; Brumell, John H; Tyers, Mike; Dirks, Peter B

    2016-06-13

    Glioblastomas (GBM) grow in a rich neurochemical milieu, but the impact of neurochemicals on GBM growth is largely unexplored. We interrogated 680 neurochemical compounds in patient-derived GBM neural stem cells (GNS) to determine the effects on proliferation and survival. Compounds that modulate dopaminergic, serotonergic, and cholinergic signaling pathways selectively affected GNS growth. In particular, dopamine receptor D4 (DRD4) antagonists selectively inhibited GNS growth and promoted differentiation of normal neural stem cells. DRD4 antagonists inhibited the downstream effectors PDGFRβ, ERK1/2, and mTOR and disrupted the autophagy-lysosomal pathway, leading to accumulation of autophagic vacuoles followed by G0/G1 arrest and apoptosis. These results demonstrate a role for neurochemical pathways in governing GBM stem cell proliferation and suggest therapeutic approaches for GBM. PMID:27300435

  2. Erianin inhibits the proliferation of T47D cells by inhibiting cell cycles, inducing apoptosis and suppressing migration

    PubMed Central

    Sun, Jing; Fu, Xueqi; Wang, Yongsen; Liu, Ye; Zhang, Yu; Hao, Tian; Hu, Xin

    2016-01-01

    Erianin is a natural product extracted from Dendrobiumchrysotoxum. To investigate the antitumor activity of Erianin in estrogen receptor (ER) positive breast cancer, we treated T47D cells with Erianin and evaluated the effects of Erianin treatment on multiple cancer-associated pathways. Erianin inhibited the proliferation of T47D cells effectively. Erianin induced apoptosis in T47D cells through reducing Bcl-2 expression and activating caspase signaling. Furthermore, it also suppressed the expression of CDKs and caused cell cycle arrest. In addition, Erianin treatment suppressed the migration of T47D cells, most likely through regulating the homeostatic expression of MPP and TIMP. Meanwhile, Erianin did not affect the proliferation of normal breast epithelial cell line MCF10A. Together, these results demonstrated that Erianin might have the potential to be an effective drug to treat the ER positive breast cancer. PMID:27508028

  3. Erianin inhibits the proliferation of T47D cells by inhibiting cell cycles, inducing apoptosis and suppressing migration.

    PubMed

    Sun, Jing; Fu, Xueqi; Wang, Yongsen; Liu, Ye; Zhang, Yu; Hao, Tian; Hu, Xin

    2016-01-01

    Erianin is a natural product extracted from Dendrobiumchrysotoxum. To investigate the antitumor activity of Erianin in estrogen receptor (ER) positive breast cancer, we treated T47D cells with Erianin and evaluated the effects of Erianin treatment on multiple cancer-associated pathways. Erianin inhibited the proliferation of T47D cells effectively. Erianin induced apoptosis in T47D cells through reducing Bcl-2 expression and activating caspase signaling. Furthermore, it also suppressed the expression of CDKs and caused cell cycle arrest. In addition, Erianin treatment suppressed the migration of T47D cells, most likely through regulating the homeostatic expression of MPP and TIMP. Meanwhile, Erianin did not affect the proliferation of normal breast epithelial cell line MCF10A. Together, these results demonstrated that Erianin might have the potential to be an effective drug to treat the ER positive breast cancer. PMID:27508028

  4. Slow and sustained nitric oxide releasing compounds inhibit multipotent vascular stem cell proliferation and differentiation without causing cell death

    SciTech Connect

    Curtis, Brandon M.; Leix, Kyle Alexander; Ji, Yajing; Glaves, Richard Samuel Elliot; Ash, David E.; Mohanty, Dillip K.

    2014-07-18

    Highlights: • Multipotent vascular stem cells (MVSCs) proliferate and differentiate. • Nitric oxide inhibits proliferation of MVSCs. • Nitric oxide inhibits MVSC differentiation to mesenchymal-like stem cells (MSCs). • Smooth muscle cells (SMCs) neither de-differentiate nor proliferate. - Abstract: Atherosclerosis is the leading cause of cerebral and myocardial infarction. It is believed that neointimal growth common in the later stages of atherosclerosis is a result of vascular smooth muscle cell (SMC) de-differentiation in response to endothelial injury. However, the claims of the SMC de-differentiation theory have not been substantiated by monitoring the fate of mature SMCs in response to such injuries. A recent study suggests that atherosclerosis is a consequence of multipotent vascular stem cell (MVSC) differentiation. Nitric oxide (NO) is a well-known mediator against atherosclerosis, in part because of its inhibitory effect on SMC proliferation. Using three different NO-donors, we have investigated the effects of NO on MVSC proliferation. Results indicate that NO inhibits MVSC proliferation in a concentration dependent manner. A slow and sustained delivery of NO proved to inhibit proliferation without causing cell death. On the other hand, larger, single-burst NO concentrations, inhibits proliferation, with concurrent significant cell death. Furthermore, our results indicate that endogenously produced NO inhibits MVSC differentiation to mesenchymal-like stem cells (MSCs) and subsequently to SMC as well.

  5. Compound Radix Sophorae Flavescentis exerts antitumor effects by inhibiting the proliferation and inducing the apoptosis of esophageal carcinoma TE-8 cells

    PubMed Central

    YANG, XIAOYU; CAI, WEIMEI; YANG, QINGHUI; LU, ZHIHONG; LI, JINSONG; YU, JIAN

    2015-01-01

    The aim of this study was to examine the effects of compound Radix Sophorae Flavescentis on the proliferation of esophageal carcinoma TE-8 cells and to elucidate the mechanisms involved. For this purpose, we incubated TE-8 cells in medium containing various concentrations (0, 0.0125, 0.025, 0.05, 0.1, 0.2, 0.4 and 0.8 mg/ml) of the compound Radix Sophorae Flavescentis injection and its effects on the proliferation of TE-8 cells were examined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. In addition, we observed the morphological changes and measured the expression levels of apoptosis-related genes (caspase-3, Bcl-2 and Bax) in the cells treated with different doses of the compound (low-dose group, 0.05 mg/ml; medium-dose group, 0.2 mg/ml; and high-dose group, 0.8 ng/ml) by reverse transcription-quantitative PCR (RT-qPCR). The apoptotic index of the cancer cells treated with different doses of the compound was determined by TUNEL assay. Our results revealed that compared with the control group (untreated cells), the proliferation of the cancer cells treated with the compound was significantly inhibited (P≤0.05); the inhibition of the proliferation of the cancer cells occured in a dose-dependent manner. Compared with the control group, the apoptotic rate of the cells in the low-dose, medium-dose and high-dose groups increased significantly (P<0.05) in a dose-dependent manner. In addition, compared with the control group, the mRNA expression of caspase-3 and Bax increased significantly in the cells treated with the compound. However, the mRNA expression of Bcl-2 markedly decreased (P<0.05). With the gradual increase in the drug concentration, the mRNA expression levels of caspase-3, Bcl-2 and Bax in the cancer cells were altered in a dose-dependent manner. In conclusion, our data demonstrate that compound Radix Sophorae Flavescentis injection significantly enhances the expression of pro-apoptotic genes in esophageal carcinoma TE-8

  6. cdk4 Deficiency Inhibits Skin Tumor Development but Does Not Affect Normal Keratinocyte Proliferation

    PubMed Central

    Rodriguez-Puebla, Marcelo L.; Miliani de Marval, Paula L.; LaCava, Margaret; Moons, David S.; Kiyokawa, Hiroaki; Conti, Claudio J.

    2002-01-01

    Most human tumors have mutations that result in deregulation of the cdk4/cyclin-Ink4-Rb pathway. Overexpression of D-type cyclins or cdk4 and inactivation of Ink4 inhibitors are common in human tumors. Conversely, lack of cyclin D1 expression results in significant reduction in mouse skin and mammary tumor development. However, complete elimination of tumor development was not observed in these models, suggesting that other cyclin/cdk complexes play an important role in tumorigenesis. Here we described the effects of cdk4 deficiency on mouse skin proliferation and tumor development. Cdk4 deficiency resulted in a 98% reduction in the number of tumors generated through the two-stage carcinogenesis model. The absence of cdk4 did not affect normal keratinocyte proliferation and both wild-type and cdk4 knockout epidermis are equally affected after topical treatment with the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA), resulting in epidermal hyperplasia. In similar fashion, cdk4 knockout keratinocytes proliferated well in an in vivo model of wound-induced proliferation. Biochemical studies in mouse epidermis showed that cdk6 activity increased twofold in cdk4-deficient mice compared to wild-type siblings. These results suggest that therapeutic approaches to inhibit cdk4 activity could provide a target to inhibit tumor development with minimal or no effect in normal tissue. PMID:12163365

  7. miR-125b inhibits osteoblastic differentiation by down-regulation of cell proliferation

    SciTech Connect

    Mizuno, Yosuke; Yagi, Ken; Tokuzawa, Yoshimi; Kanesaki-Yatsuka, Yukiko; Suda, Tatsuo; Katagiri, Takenobu; Fukuda, Toru; Maruyama, Masayoshi; Okuda, Akihiko; Amemiya, Tomoyuki; Kondoh, Yasumitsu; Tashiro, Hideo; Okazaki, Yasushi

    2008-04-04

    Although various microRNAs regulate cell differentiation and proliferation, no miRNA has been reported so far to play an important role in the regulation of osteoblast differentiation. Here we describe the role of miR-125b in osteoblastic differentiation in mouse mesenchymal stem cells, ST2, by regulating cell proliferation. The expression of miR-125b was time-dependently increased in ST2 cells, and the increase in miR-125b expression was attenuated in osteoblastic-differentiated ST2 cells induced by BMP-4. The transfection of exogenous miR-125b inhibited proliferation of ST2 cells and caused inhibition of osteoblastic differentiation. In contrast, when the endogenous miR-125b was blocked by transfection of its antisense RNA molecule, alkaline phosphatase activity after BMP-4 treatment was elevated. These results strongly suggest that miR-125b is involved in osteoblastic differentiation through the regulation of cell proliferation.

  8. Dehydroleucodine inhibits vascular smooth muscle cell proliferation in G2 phase.

    PubMed

    Cruzado, M; Castro, C; Fernandez, D; Gomez, L; Roque, M; Giordano, O E; Lopez, L A

    2005-11-01

    Vascular smooth muscle cell (VSMC) proliferation plays an important role in the development of atherosclerosis and in the vascular changes seen in hypertension. Dehydroleucodine (DhL) is a sesquiterpene lactone that inhibits cell proliferation in plant cells. In this paper, we study the effect of DhL in the proliferation of VSMCs stimulated with 10% fetal bovine serum (FBS). Very low concentrations of DhL (2-6 microM) inhibited VSMC proliferation and induced cell accumulation in G2. DhL did not affect the dynamics of 3H-thymidine incorporation, and did not modify either the activity of DNA polymerase or the incorporation of deoxyribonucleotides in an in vitro assay. Moreover, DhL did not induce apoptosis in VSMCs. These results indicate that DhL, in very low concentration, induces a transient arrest of VSMCs in G2. Our data show that VSMCs are especially sensitive to DhL effect, suggesting that DhL could be potentially useful to prevent the vascular pathological changes seen in hypertension and other vascular diseases. PMID:16309576

  9. Polyamine analog TBP inhibits proliferation of human K562 chronic myelogenous leukemia cells by induced apoptosis

    PubMed Central

    WANG, QING; WANG, YAN-LIN; WANG, KAI; YANG, JIAN-LIN; CAO, CHUN-YU

    2015-01-01

    The aim of the present study was to investigate the effects of the novel polyamine analog tetrabutyl propanediamine (TBP) on the growth of K562 chronic myelogenous leukemia (CML) cells and the underlying mechanism of these effects. MTT was used for the analysis of cell proliferation and flow cytometry was performed to analyze cell cycle distribution. DNA fragmentation analysis and Annexin V/propidium iodide double staining were used to identify apoptotic cells. The activity of the key enzymes in polyamine catabolism was detected using chemiluminescence. TBP can induce apoptosis and significantly inhibit K562 cell proliferation in a time- and dose-dependent manner. TBP treatment significantly induced the enzyme activity of spermine oxidase and acetylpolyamine oxidase in K562 cells, and also enhanced the inhibitory effect of the antitumor drug doxorubicin on K562 cell proliferation. As a novel polyamine analog, TBP significantly inhibited proliferation and induced apoptosis in K562 cells by upregulating the activity of the key enzymes in the polyamine catabolic pathways. TBP also increased the sensitivity of the K562 cells to the antitumor drug doxorubicin. These data indicate an important potential value of TBP for clinical therapy of human CML. PMID:25435975

  10. An ethanolic extract of Angelica gigas improves atherosclerosis by inhibiting vascular smooth muscle cell proliferation

    PubMed Central

    Jang, Ja Young; Kim, Jihyun; Cai, Jingmei; Kim, Youngeun; Shin, Kyungha; Kim, Tae-Su; Lee, Sung-Pyo; Park, Sung Kyeong

    2014-01-01

    The effects of an ethanolic extract of Angelica gigas (EAG) on the vascular smooth muscle cell (VSMC) proliferation and high-cholesterol diet-induced hypercholesterolemia and atherosclerosis were investigated. Rat aortic VSMCs were stimulated with platelet-derived growth factor-BB (25 ng/mL) for the induction of DNA synthesis and cell proliferation. EAG (1-10 µg/mL) significantly inhibited both the thymidine incorporation and cell proliferation in a concentration-dependent manner. Hypercholesterolemia was induced by feeding male New Zealand white rabbits with 0.5% cholesterol in diet for 10 weeks, during which EAG (1% in diet) was given for the final 8 weeks after 2-week induction of hypercholesterolemia. Hypercholesterolemic rabbits exhibited great increases in serum total cholesterol and low-density lipoproteins (LDL) levels, and finally severe atheromatous plaque formation covering 28.4% of the arterial walls. EAG significantly increased high-density lipoproteins (HDL), slightly decreased LDL, and potentially reduced the atheroma area to 16.6%. The results indicate that EAG attenuates atherosclerosis not only by inhibiting VASC proliferation, but also by increasing blood HDL levels. Therefore, it is suggested that EAG could be an alternative or an adjunct therapy for the improvement of hypercholesterolemia and atherosclerosis. PMID:24999363

  11. Inhibition of cervical carcinoma cell line proliferation by the introduction of a bovine papillomavirus regulatory gene.

    PubMed Central

    Hwang, E S; Riese, D J; Settleman, J; Nilson, L A; Honig, J; Flynn, S; DiMaio, D

    1993-01-01

    Human papillomavirus (HPV) E6 and E7 oncogenes are expressed in the great majority of human cervical carcinomas, whereas the viral E2 regulatory gene is usually disrupted in these cancers. To investigate the roles of the papillomavirus E2 genes in the development and maintenance of cervical carcinoma, the bovine papillomavirus (BPV) E2 gene was acutely introduced into cervical carcinoma cell lines by infection with high-titer stocks of simian virus 40-based recombinant viruses. Expression of the BPV E2 protein in HeLa, C-4I, and MS751 cells results in specific inhibition of the expression of the resident HPV type 18 (HPV18) E6 and E7 genes and in inhibition of cell growth. HeLa cells, in which HPV gene expression is nearly completely abolished, undergo a dramatic and rapid inhibition of proliferation, which appears to be largely a consequence of a block in progression from the G1 to the S phase of the cell cycle. Loss of HPV18 gene expression in HeLa cells is also accompanied by a marked increase in the level of the cellular p53 tumor suppressor protein, apparently as a consequence of abrogation of HPV18 E6-mediated destabilization of p53. The proliferation of HT-3 cells, a human cervical carcinoma cell line devoid of detectable HPV DNA, is also inhibited by E2 expression, whereas two other epithelial cell lines that do not contain HPV DNA are not inhibited. Thus, a number of cervical carcinoma cell lines are remarkably sensitive to growth inhibition by the E2 protein. Although BPV E2-mediated inhibition of HPV18 E6 and E7 expression may contribute to growth inhibition in some of the cervical carcinoma cell lines, the BPV E2 protein also appears to exert a growth-inhibitory effect that is independent of its effects on HPV gene expression. Images PMID:8389903

  12. Peroxisome proliferator-activated receptor gamma (PPARγ) in yellow catfish Pelteobagrus fulvidraco: molecular characterization, mRNA expression and transcriptional regulation by insulin in vivo and in vitro.

    PubMed

    Zheng, Jia-Lang; Zhuo, Mei-Qin; Luo, Zhi; Pan, Ya-Xiong; Song, Yu-Feng; Huang, Chao; Zhu, Qing-Ling; Hu, Wei; Chen, Qi-Liang

    2015-02-01

    Peroxisome proliferator-activated receptor gamma (PPARγ) is ligand-inducible transcription factor and has important roles in lipid metabolism, cell proliferation and inflammation. In the present study, yellow catfish Pelteobagrus fulvidraco PPARγ cDNA was isolated from liver by RT-PCR and RACE, and its molecular characterization and transcriptional regulation by insulin in vivo and in vitro were determined. The generation of PPARγ1 and PPARγ2 was due to alternative promoter of PPARγ gene. PPARγ1 and PPARγ2 mRNA covered 2426 bp and 2537 bp, respectively, with an open reading frame (ORF) of 1584 bp encoding 527 amino acid residues. Yellow catfish PPARγ gene was organized in a manner similar to that of their mammalian homologs, implying a modular organization of the protein's domains. A comparison between the yellow catfish PPARγ amino acid sequence and the correspondent sequences of several other species revealed the identity of 55-76.2%. Two PPARγ transcripts (PPARγ1 and PPARγ2) mRNAs were expressed in a wide range of tissues, but the abundance of each PPARγ mRNA showed the tissue- and developmental stage-dependent expression patterns. Intraperitoneal injection of insulin in vivo significantly stimulated the mRNA expression of total PPARγ and PPARγ1, but not PPARγ2 in the liver of yellow catfish. In contrast, incubation of hepatocytes with insulin in vitro increased the mRNA levels of PPARγ1, PPARγ2 and total PPARγ. To our knowledge, for the first time, the present study provides evidence that PPARγ1 and PPARγ2 are differentially expressed with and among tissues during different developmental stages and also regulated by insulin both in vivo and in vitro, which serves to increase our understanding on PPARγ physiological function in fish. PMID:25637673

  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

    SciTech Connect

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

    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. Inhibition of T-lymphocyte proliferation by cucurbitacins from Picrorhiza scrophulariaeflora.

    PubMed

    Smit, H F; van den Berg, A J; Kroes, B H; Beukelman, C J; Quarles van Ufford, H C; van Dijk, H; Labadie, R P

    2000-09-01

    Two cucurbitacin aglycons were isolated from the dried rhizomes of Picrorhiza scrophulariaeflora and were identified as 25-acetoxy-2,3, 16,20-tetrahydroxy-9-methyl-19-norlanosta-5,23-dien-22-one (picracin, 1) and 2,3,16,20,25-pentahydroxy-9-methyl-19-norlanosta-5, 23-dien-22-one (deacetylpicracin, 2). Both compounds inhibit mitogen-induced T-lymphocyte proliferation at an IC(50) value of 1 microM. PMID:11000045

  15. β-catenin knockdown inhibits the proliferation of human glioma cells in vitro and in vivo

    PubMed Central

    WANG, ZHONG; CHEN, QIANXUE

    2016-01-01

    β-catenin is a crucial oncogene that is capable of regulating cancer progression. The aim of the present study was to clarify whether β-catenin was associated with the proliferation and progress of glioma. In order to knockdown the expression of β-catenin in human U251 glioma cells, three pairs of small interfering (si)RNA were designed and synthesized and the most effective siRNA was selected and used for silencing the endogenous β-catenin, which was detected by western blot analysis and reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Proliferation was subsequently detected using a methylthiazolyl-tetrazolium bromide assay and the results demonstrated that knockdown of β-catenin significantly inhibited the proliferation of U251 cells in a time- and dose-dependent manner (P<0.01). Cell apoptosis rate was analyzed using flow cytometry and Annexin V-fluorescein isothiocyanate/propidium iodide staining demonstrated that β-catenin siRNA significantly increased the apoptosis of U251 cells (P<0.01). Furthermore, the results of an in vitro scratch assay demonstrated that β-catenin silencing suppressed the proliferation of U251 cells, as compared with the control group (P<0.01). In vivo, β-catenin expression levels in U251 cells were significantly inhibited (P<0.01) following β-catenin short hairpin (sh)RNA lentiviral-vector transfection, as detected by western blot analysis and RT-qPCR. Tumorigenicity experiments demonstrated that β-catenin inhibition significantly increased the survival rate of nude mice. The results of the present study demonstrated that knockdown of β-catenin expression significantly inhibited the progression of human glioma cancer cells, in vitro and in vivo; thus suggesting that β-catenin silencing may be a novel therapy for the treatment of human glioma. PMID:26998037

  16. Alpha lipoic acid inhibits proliferation and epithelial mesenchymal transition of thyroid cancer cells.

    PubMed

    Jeon, Min Ji; Kim, Won Gu; Lim, Seonhee; Choi, Hyun-Jeung; Sim, Soyoung; Kim, Tae Yong; Shong, Young Kee; Kim, Won Bae

    2016-01-01

    The naturally occurring short-chain fatty acid, α-lipoic acid (ALA) is a powerful antioxidant which is clinically used for treatment of diabetic neuropathy. Recent studies suggested the possibility of ALA as a potential anti-cancer agent, because it could activate adenosine monophosphate activated protein kinase (AMPK) and inhibit transforming growth factor-β (TGFβ) pathway. In this study, we evaluate the effects of ALA on thyroid cancer cell proliferation, migration and invasion. We performed in vitro cell proliferation analysis using BCPAP, HTH-83, CAL-62 and FTC-133 cells. ALA suppressed thyroid cancer cell proliferation through activation of AMPK and subsequent down-regulation of mammalian target of rapamycin (mTOR)-S6 signaling pathway. Low-dose ALA, which had minimal effects on cell proliferation, also decreased cell migration and invasion of BCPAP, CAL-62 and HTH-83 cells. ALA inhibited epithelial mesenchymal transition (EMT) evidently by increase of E-cadherin and decreases of activated β-catenin, vimentin, snail, and twist in these cells. ALA suppressed TGFβ production and inhibited induction of p-Smad2 and twist by TGFβ1 or TGFβ2. These findings indicate that ALA reduces cancer cell migration and invasion through suppression of TGFβ production and inhibition of TGFβ signaling pathways in thyroid cancer cells. ALA also significantly suppressed tumor growth in mouse xenograft model using BCPAP and FTC-133 cells. This is the first study to show anti-cancer effect of ALA on thyroid cancer cells. ALA could be a potential therapeutic agent for treatment of advanced thyroid cancer, possibly as an adjuvant therapy with other systemic therapeutic agents. PMID:26463583

  17. Spiruchostatin A Inhibits Proliferation and Differentiation of Fibroblasts from Patients with Pulmonary Fibrosis

    PubMed Central

    Davies, Elizabeth R.; Haitchi, Hans Michael; Thatcher, Thomas H.; Sime, Patricia J.; Kottmann, R. Matthew; Ganesan, Arasu; Packham, Graham; O'Reilly, Katherine M. A.

    2012-01-01

    Idiopathic pulmonary fibrosis (IPF) is a progressive scarring disorder characterized by the proliferation of interstitial fibroblasts and the deposition of extracellular matrix causing impaired gas exchange. Spiruchostatin A (SpA) is a histone deacetylase inhibitor (HDI) with selectivity toward Class I enzymes, which distinguishes it from other nonspecific HDIs that are reported to inhibit (myo)fibroblast proliferation and differentiation. Because the selectivity of HDIs may be important clinically, we postulated that SpA inhibits the proliferation and differentiation of IPF fibroblasts. Primary fibroblasts were grown from lung biopsy explants obtained from patients with IPF or from normal control subjects, using two-dimensional or three-dimensional culture models. The effect of SpA on fibroproliferation in serum-containing medium ± transforming growth factor (TGF)–β1 was quantified by methylene blue binding. The acetylation of histone H3, the expression of the cell-cycle inhibitor p21waf1, and the myofibroblast markers α–smooth muscle actin (α-SMA) and collagens I and III were determined by Western blotting, quantitative RT-PCR, immunofluorescent staining, or colorimetry. SpA inhibited the proliferation of IPF or normal fibroblasts in a time-dependent and concentration-dependent manner (concentration required to achieve 50% inhibition = 3.8 ± 0.4 nM versus 7.8 ± 0.2 nM, respectively; P < 0.05), with little cytotoxicity. Western blot analyses revealed that SpA caused a concentration-dependent increase in histone H3 acetylation, paralleling its antiproliferative effect. SpA also increased p21waf1 expression, suggesting that direct cell-cycle regulation was the mechanism of inhibiting proliferation. Although treatment with TGF-β1 induced myofibroblast differentiation associated with increased expression of α-SMA, collagen I and collagen III and soluble collagen release, these responses were potently inhibited by SpA. These data support the concept that

  18. Heparin inhibits mesangial cell proliferation in habu-venom-induced glomerular injury.

    PubMed Central

    Coffey, A. K.; Karnovsky, M. J.

    1985-01-01

    The authors have investigated the ability of anticoagulant heparin and nonanticoagulant heparin to inhibit mesangial-cell proliferation after the administration of habu (Trimeresurus flavorivids) snake venom to rats. Rats given injected habu venom exhibited glomerular capillary cystic lesions 6 to 24 hours later, and marked mesangial proliferation was noted within the cyst after 3 days. At 7 days 87% of these lesions (nodules) contained primarily mesangial cells embedded in a dense matrix and fibrin. A decrease in the frequency of nodules and the persistence of cysts indicate effective antiproliferative treatment. When anticoagulant heparin treatment extended from 18 hours after venom administration until sacrifice at 7 days, the percentage of nodules was reduced to 40%. Nonanticoagulant heparins resulted in some, but inconsistent, inhibition of mesangial-cell proliferation. The mechanism of the antiproliferative action of heparin on mesangial cells is not known but may be similar to that for vascular smooth muscle growth regulation. The authors suggest that endogenous heparin in the glomerular basement membrane and mesangial matrix may exert an antiproliferative effect under normal conditions. Loss of this inhibition due to glomerular damage might be reversed by the addition of exogenous heparin. Images Figure 1 PMID:3875292

  19. Lactobacillus helveticus SBT2171 Inhibits Lymphocyte Proliferation by Regulation of the JNK Signaling Pathway

    PubMed Central

    Yamashita, Maya; Shiozaki, Takuya; Endo, Tsutomu; Ukibe, Ken; Uenishi, Hiroshi; Kadooka, Yukio; Moriya, Tomohiro; Nakagawa, Hisako; Nakayama, Yosuke; Miyazaki, Tadaaki

    2014-01-01

    Lactobacillus helveticus SBT2171 (LH2171) is a lactic acid bacterium with high protease activity and used in starter cultures in the manufacture of cheese. We recently reported that consumption of cheese manufactured using LH2171 alleviated symptoms of dextran sodium sulfate (DSS)-induced colitis in mice. In this study, we have examined whether LH2171 itself exerts an inhibitory effect on the excessive proliferation of lymphocytes. We found that LH2171 inhibited the proliferation of LPS-stimulated mouse T and B cells, and the human lymphoma cell lines, Jurkat and BJAB. Cell cycle analysis showed an accumulation of LH2171-treated BJAB cells in the G2/M phase. Further, phosphorylation of c-Jun N-terminal kinase (JNK) and c-Jun was reduced by LH2171 in BJAB cells. Subsequently, expression of cell division cycle 2 (CDC2), regulated by the JNK signaling pathway and essential for G2/M phase progression, was inhibited by LH2171. It was also demonstrated that intraperitoneal administration of LH2171 strongly alleviated symptoms of collagen-induced arthritis (CIA) in mice. These findings suggest that LH2171 inhibits the proliferation of lymphocytes through a suppression of the JNK signaling pathway and exerts an immunosuppressive effect in vivo. PMID:25268890

  20. Interleukin 4 inhibits in vitro proliferation of leukemic and normal human B cell precursors.

    PubMed Central

    Pandrau, D; Saeland, S; Duvert, V; Durand, I; Manel, A M; Zabot, M T; Philippe, N; Banchereau, J

    1992-01-01

    In the present study, we have investigated the effects of IL-4 on the proliferation and differentiation of leukemic and normal human B cell precursors (BCP). We have demonstrated that IL-4 significantly inhibited spontaneous [3H]thymidine ([3H]-TdR) incorporation by leukemic blasts from some B lineage acute lymphoblastic leukemia (BCP-ALL) patients (8 of 14). Furthermore, IL-4 was found to suppress the spontaneous and factor-dependent (IL-7 and IL-3) proliferation of normal BCP (CD10+ surface [s] IgM- cells) isolated from fetal bone marrow. Maximum growth inhibition of either leukemic or normal BCP was reached at low IL-4 concentrations (10 U/ml), and the effect was specifically neutralized by anti-IL-4 antibody. IL-4 was further found to induce the expression of CD20 antigen on BCP-ALL cells from a number of the cases examined (5 of 8), but in contrast to leukemic cells, IL-4 failed to induce CD20 antigen on normal BCP. Finally, IL-4 was found to induce neither the expression of cytoplasmic mu chain, nor the appearance of sIgM+ cells in cultures of normal or leukemic BCP. Our data indicate that IL-4 has the potential to inhibit cell proliferation in leukemic and normal human B lymphopoiesis but is unable to drive the transition from BCP to mature B cells. Images PMID:1385474

  1. Bone morphogenetic protein signalling suppresses wound-induced skin repair by inhibiting keratinocyte proliferation and migration

    PubMed Central

    Lewis, Christopher J.; Mardaryev, Andrei N.; Poterlowicz, Krzysztof; Sharova, Tatyana Y.; Aziz, Ahmar; Sharpe, David T.; Botchkareva, Natalia V.; Sharov, Andrey A.

    2013-01-01

    Bone morphogenetic protein (BMP) signalling plays a key role in the control of skin development and postnatal remodelling by regulating keratinocyte proliferation, differentiation and apoptosis. To study the role of BMPs in wound-induced epidermal repair, we used transgenic mice overexpressing the BMP downstream component Smad1 under the control of a K14 promoter as an in vivo model, as well as ex vivo and in vitro assays. K14-caSmad1 mice exhibited retarded wound healing associated with significant inhibition of proliferation and increased apoptosis in healing wound epithelium. Furthermore, microarray and qRT-PCR analyses revealed decreased expression of a number of cytoskeletal/cell motility-associated genes including wound-associated keratins (Krt16, Krt17) and Myo5a, in the epidermis of K14-caSmad1 mice versus wild-type controls during wound healing. BMP treatment significantly inhibited keratinocyte migration ex vivo, and primary keratinocytes of K14-caSmad1 mice showed retarded migration compared to wild-type controls. Finally, siRNA-mediated silencing of Bmpr-1B in primary mouse keratinocytes accelerated cell migration and was associated with increased expression of Krt16, Krt17 and Myo5a compared to controls. Thus, this study demonstrates that BMPs inhibit keratinocyte proliferation, cytoskeletal organization and migration in regenerating skin epithelium during wound healing, and raises a possibility for using BMP antagonists for the management of chronic wounds. PMID:24126843

  2. PPARγ inhibits ovarian cancer cells proliferation through upregulation of miR-125b.

    PubMed

    Luo, Shuang; Wang, Jidong; Ma, Ying; Yao, Zhenwei; Pan, Hongjuan

    2015-06-26

    miR-125b has essential roles in coordinating tumor proliferation, angiogenesis, invasiveness, metastasis and chemotherapy recurrence. In ovarian cancer miR-125b has been shown to be downregulated and acts as a tumor suppressor by targeting proto-oncogene BCL3. PPARγ, a multiple functional transcription factor, has been reported to have anti-tumor effects through inhibition of proliferation and induction of differentiation and apoptosis by targeting the tumor related genes. However, it is unclear whether miR-125b is regulated by PPARγ in ovarian cancer. In this study, we demonstrated that the miR-125b downregulated in ovarian cancer tissues and cell lines. Ligands-activated PPARγ suppressed proliferation of ovarian cancer cells and this PPARγ-induced growth inhibition is mediated by the upregulation of miR-125b. PPARγ promoted the expression of miR-125b by directly binding to the responsive element in miR-125b gene promoter region. Thus, our results suggest that PPARγ can induce growth suppression of ovarian cancer by upregulating miR-125b which inhibition of proto-oncogene BCL3. These findings will extend our understanding of the function of PPARγ in tumorigenesis and miR-125b may be a therapeutic intervention of ovarian cancer. PMID:25944662

  3. Interferon-alpha inhibits murine macrophage transforming growth factor-beta mRNA expression.

    PubMed

    Dhanani, S; Huang, M; Wang, J; Dubinett, S M

    1994-06-01

    Transforming growth factor-beta (TGF-beta), a multifunctional polypeptide is produced by a wide variety of cells and regulates a broad array of physiological and pathological functions. TGF-beta appears to play a central role in pulmonary fibrosis and may contribute to tumor-associated immunosuppression. Alveolar macrophages are a rich source of TGF-beta and are intimately involved in lung inflammation. We therefore chose to study TGF-beta regulation in murine alveolar macrophages as well as an immortalized peritoneal macrophage cell line (IC-21). Murine macrophages were incubated with cytokines to evaluate their role in regulating TGF-beta mRNA expression. We conclude that IFN-alpha downregulates TGF-beta mRNA expression in murine macrophages. PMID:8088926

  4. D-Glucosamine inhibits proliferation of human cancer cells through inhibition of p70S6K

    SciTech Connect

    Oh, Hyun-Ji; Lee, Jason S.; Song, Dae-Kyu; Shin, Dong-Hoon; Jang, Byeong-Churl; Suh, Seong-Il; Park, Jong-Wook; Suh, Min-Ho; Baek, Won-Ki . E-mail: wonki@dsmc.or.kr

    2007-09-07

    Although D-glucosamine has been reported as an inhibitor of tumor growth both in vivo and in vitro, the mechanism for the anticancer effect of D-glucosamine is still unclear. Since there are several reports suggesting D-glucosamine inhibits protein synthesis, we examined whether D-glucosamine affects p70S6 K activity, an important signaling molecule involved in protein translation. In the present study, we found D-glucosamine inhibited the activity of p70S6K and the proliferation of DU145 prostate cancer cells and MDA-MB-231 breast cancer cells. D-Glucosamine decreased phosphorylation of p70S6K, and its downstream substrates RPS6, and eIF-4B, but not mTOR and 4EBP1 in DU145 cells, suggesting that D-glucosamine induced inhibition of p70S6K is not through the inhibition of mTOR. In addition, D-glucosamine enhanced the growth inhibitory effects of rapamycin, a specific inhibitor of mTOR. These findings suggest that D-glucosamine can inhibit growth of cancer cells through dephosphorylation of p70S6K.

  5. Tunicamycin-induced inhibition of protein secretion into culture medium of Arabidopsis T87 suspension cells through mRNA degradation on the endoplasmic reticulum.

    PubMed

    Iwata, Yuji; Hayashi, Noriko; Tabara, Kazuki; Mishiba, Kei-Ichiro; Koizumi, Nozomu

    2016-06-01

    The N-glycosylation inhibitor tunicamycin triggers endoplasmic reticulum stress response and inhibits efficient protein secretion in eukaryotes. Using Arabidopsis suspension cells, we showed that the reduced secretion of mannose-binding lectin 1 (MBL1) protein by tunicamycin is accompanied by a significant decrease in MBL1 mRNA, suggesting that mRNA destabilization is the major cause of the inhibition of protein secretion in plants. PMID:26923805

  6. MiRNA-125a-5p inhibits glioblastoma cell proliferation and promotes cell differentiation by targeting TAZ

    SciTech Connect

    Yuan, Jian; Xiao, Gelei; Peng, Gang; Liu, Dingyang; Wang, Zeyou; Liao, Yiwei; Liu, Qing; Wu, Minghua; Yuan, Xianrui

    2015-02-06

    Highlights: • Expression of miR-125a-5p is inversely correlated with that of TAZ in glioma cells. • MiR-125a-5p represses TAZ expression in glioma cells. • MiR-125a-5p directly targets the 3′ UTR of TAZ mRNA and promotes its degradation. • MiR-125a-5p represses CTGF and survivin via TAZ, and inhibits glioma cell growth. • MiR-125a-5p inhibits the stem cell features of HFU-251 MG cells. - Abstract: Glioblastoma (GBM) is the most lethal brain tumor due to the resistance to conventional therapies, such as radiotherapy and chemotherapy. TAZ, an important mediator of the Hippo pathway, was found to be up-regulated in diverse cancers, including in GBM, and plays important roles in tumor initiation and progression. However, little is known about the regulation of TAZ expression in tumors. In this study, we found that miR-125a-5p is an important regulator of TAZ in glioma cells by directly targeting the TAZ 3′ UTR. MiR-125a-5p levels are inversely correlated with that of TAZ in normal astrocytes and a panel of glioma cell lines. MiR-125a-5p represses the expression of TAZ target genes, including CTGF and survivin, and inhibits cell proliferation and induces the differentiation of GBM cells; whereas over-expression of TAZ rescues the effects of miR-125a-5p. This study revealed a mechanism for TAZ deregulation in glioma cells, and also demonstrated a tumor suppressor role of miR-125a-5p in glioblastoma cells.

  7. Iptakalim inhibits PDGF-BB-induced human airway smooth muscle cells proliferation and migration

    SciTech Connect

    Liu, Wenrui; Kong, Hui; Zeng, Xiaoning; Wang, Jingjing; Wang, Zailiang; Yan, Xiaopei; Wang, Yanli; Xie, Weiping Wang, Hong

    2015-08-15

    Chronic airway diseases are characterized by airway remodeling which is attributed partly to the proliferation and migration of airway smooth muscle cells (ASMCs). ATP-sensitive potassium (K{sub ATP}) channels have been identified in ASMCs. Mount evidence has suggested that K{sub ATP} channel openers can reduce airway hyperresponsiveness and alleviate airway remodeling. Opening K{sup +} channels triggers K{sup +} efflux, which leading to membrane hyperpolarization, preventing Ca{sup 2+}entry through closing voltage-operated Ca{sup 2+} channels. Intracellular Ca{sup 2+} is the most important regulator of muscle contraction, cell proliferation and migration. K{sup +} efflux decreases Ca{sup 2+} influx, which consequently influences ASMCs proliferation and migration. As a K{sub ATP} channel opener, iptakalim (Ipt) has been reported to restrain the proliferation of pulmonary arterial smooth muscle cells (PASMCs) involved in vascular remodeling, while little is known about its impact on ASMCs. The present study was designed to investigate the effects of Ipt on human ASMCs and the mechanisms underlying. Results obtained from cell counting kit-8 (CCK-8), flow cytometry and 5-ethynyl-2′-deoxyuridine (EdU) incorporation showed that Ipt significantly inhibited platelet-derived growth factor (PDGF)-BB-induced ASMCs proliferation. ASMCs migration induced by PDGF-BB was also suppressed by Ipt in transwell migration and scratch assay. Besides, the phosphorylation of Ca{sup 2+}/calmodulin-dependent kinase II (CaMKII), extracellular regulated protein kinases 1/2 (ERK1/2), protein kinase B (Akt), and cyclic adenosine monophosphate (cAMP) response element binding protein (CREB) were as well alleviated by Ipt administration. Furthermore, we found that the inhibition of Ipt on the PDGF-BB-induced proliferation and migration in human ASMCs was blocked by glibenclamide (Gli), a selective K{sub ATP} channel antagonist. These findings provide a strong evidence to support that Ipt

  8. Triptolide inhibits proliferation of Epstein–Barr virus-positive B lymphocytes by down-regulating expression of a viral protein LMP1

    SciTech Connect

    Zhou, Heng; Guo, Wei; Long, Cong; Wang, Huan; Wang, Jingchao; Sun, Xiaoping

    2015-01-16

    Highlights: • Triptolide inhibits proliferation of EBV-positive lymphoma cells in vitro and in vivo. • Triptolide reduces expression of LMP1 by decreasing its transcription level. • Triptolide inhibits ED-L1 promoter activity. - Abstract: Epstein–Barr virus (EBV) infects various types of cells and mainly establishes latent infection in B lymphocytes. The viral latent membrane protein 1 (LMP1) plays important roles in transformation and proliferation of B lymphocytes infected with EBV. Triptolide is a compound of Tripterygium extracts, showing anti-inflammatory, immunosuppressive, and anti-cancer activities. In this study, it is determined whether triptolide inhibits proliferation of Epstein–Barr virus-positive B lymphocytes. The CCK-8 assays were performed to examine cell viabilities of EBV-positive B95-8 and P3HR-1 cells treated by triptolide. The mRNA and protein levels of LMP1 were examined by real time-PCR and Western blotting, respectively. The activities of two LMP1 promoters (ED-L1 and TR-L1) were determined by Dual luciferase reportor assay. The results showed that triptolide inhibited the cell viability of EBV-positive B lymphocytes, and the over-expression of LMP1 attenuated this inhibitory effect. Triptolide decreased the LMP1 expression and transcriptional levels in EBV-positive B cells. The activity of LMP1 promoter ED-L1 in type III latent infection was strongly suppressed by triptolide treatment. In addition, triptolide strongly reduced growth of B95-8 induced B lymphoma in BALB/c nude mice. These results suggest that triptolide decreases proliferation of EBV-induced B lymphocytes possibly by a mechanism related to down-regulation of the LMP1 expression.

  9. Structural determinants of resveratrol for cell proliferation inhibition potency: experimental and docking studies of new analogs.

    PubMed

    Mazué, Frédéric; Colin, Didier; Gobbo, Jessica; Wegner, Maria; Rescifina, Antonio; Spatafora, Carmela; Fasseur, Dominique; Delmas, Dominique; Meunier, Philippe; Tringali, Corrado; Latruffe, Norbert

    2010-07-01

    Resveratrol is the subject of intense research because of the abundance of this compound in the human diet and as one of the most valuable natural chemopreventive agents. Further advances require new resveratrol analogs be used to identify the structural determinants of resveratrol for the inhibition potency of cell proliferation by comparing experimental and docking studies. Therefore, we synthesized new trans/(E)- and cis/(Z)-resveratrol - analogs not reported to date - by modifying the hydroxylation pattern of resveratrol and a double bond geometry. We included them in a larger panel of 14 molecules, including (Z)-3,5,4'-trimethoxystilbene, the most powerful molecule that is used as reference. Using a docking model complementary to experimental studies on the proliferation inhibition of the human colorectal tumor SW480 cell line, we show that methylation is the determinant substitution in inhibition efficacy, but only in molecules bearing a Z configuration. Most of the synthetic methylated derivatives (E or Z) stop mitosis at the M phase and lead to polyploid cells, while (E)-resveratrol inhibits cells at the S phase. Docking studies show that almost all of the docked structures of (Z)-polymethoxy isomers, but not most of the (E)-polymethoxy isomers substantially overlap the docked structure of combretastatin A-4, taken as reference ligand at the colchicine-tubulin binding site. PMID:20395019

  10. Compound 13, an α1-selective small molecule activator of AMPK, potently inhibits melanoma cell proliferation.

    PubMed

    Hu, Xueqing; Jiang, Fangzhen; Bao, Qi; Qian, Huan; Fang, Quan; Shao, Zheren

    2016-01-01

    It is vital to develop new therapeutic agents for the treatment of melanoma. In the current study, we studied the potential effect of Compound 13 (C13), a novel α1-selective AMP-activated protein kinase (AMPK) activator, in melanoma cells. We showed that C13 exerted mainly cytostatic, but not cytotoxic activities in melanoma cells. C13 potently inhibited proliferation in melanoma cell lines (A375, OCM-1 and B16), but not in B10BR melanocytes. Meanwhile, the AMPK activator inhibited melanoma cell cycle progression by inducing G1-S arrest. Significantly, we failed to detect significant melanoma cell death or apoptosis after the C13 treatment. For the mechanism study, we showed that C13 activated AMPK and inhibited mammalian target of rapamycin complex 1 (mTORC1) signaling in melanoma cells through interaction with the α1 subunit. Short hairpin RNA (shRNA)-mediated knockdown of AMPKα1 not only blocked C13-mediated AMPK activation but also abolished its antiproliferative activity against melanoma cells. Together, these results show that C13 inhibits melanoma cell proliferation through activating AMPK signaling. Our data suggest that C13 along with other small molecular AMPK activators may be beneficial for patients with melanoma. PMID:26271666