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Sample records for inhibits apoptosis induced

  1. Cold-inducible RNA-binding protein inhibits neuron apoptosis through the suppression of mitochondrial apoptosis.

    PubMed

    Zhang, Hai-Tao; Xue, Jing-Hui; Zhang, Zhi-Wen; Kong, Hai-Bo; Liu, Ai-Jun; Li, Shou-Chun; Xu, Dong-Gang

    2015-10-05

    Cold-inducible RNA-binding protein (CIRP) is induced by mild hypothermia in several mammals, but the precise mechanism by which CIRP mediates hypothermia-induced neuroprotection remains unknown. We aimed to investigate the molecular mechanisms by which CIRP protects the nervous system during mild hypothermia. Rat cortical neurons were isolated and cultured in vitro under mild hypothermia (32°C). Apoptosis was measured by annexin V and propidium iodide staining, visualized by flow cytometry. Neuron ultrastructure was visualized by transmission electron microscopy. CIRP overexpression and knockdown were achieved via infection with pL/IRES/GFP-CIRP and pL/shRNA/F-CIRP-A lentivirus. RT(2) Profiler PCR Array Pathway Analysis and western blotting were used to evaluate the effects of CIRP overexpresion/knockdown on the neurons׳ transcriptome. Neuron late apoptosis was significantly reduced at day 7 of culture by 12h hypothermia, but neuron ultrastructure remained relatively intact. RT(2) Profiler PCR Array Pathway Analysis of 84 apoptosis pathway-associated factors revealed that mild hypothermia and CIRP overexpression induce similar gene expression profiles, specifically alterations of genes implicated in the mitochondrial apoptosis pathway. Mild hypothermia-treated neurons up-regulated 12 and down-regulated 38 apoptosis pathway-associated genes. CIRP-overexpressing neurons up-regulated 15 and down-regulated 46 genes. CIRP-knocked-down hypothermia-treated cells up-regulated 9 and down-regulated 40 genes. Similar results were obtained at the protein level. In conclusion, CIRP may inhibit neuron apoptosis through the suppression of the mitochondria apoptosis pathway during mild hypothermia.

  2. Osthole induces lung cancer cell apoptosis through inhibition of inhibitor of apoptosis family proteins

    PubMed Central

    Xu, Xiao-Man; Zhang, Man-Li; Zhang, Yi; Zhao, Li

    2016-01-01

    In the present study, we investigated the effects and mechanisms of Osthole on the apoptosis of non-small cell lung cancer (NSCLC) cells and its synergistic effect with Embelin. Our results revealed that treatment with both Osthole and Embelin inhibited cell proliferation. Notably, combination treatment of Osthole and Embelin inhibited cell proliferation more significantly compared with monotherapy. In addition, morphological analysis and Annexin V/propidium iodide analysis revealed that the combination of Osthole and Embelin enhanced their effect on cell apoptosis. We further examined the effect of Osthole on the expression of inhibitor of apoptosis protein (IAP) family proteins. That treatment of A549 lung cancer cells with various concentrations of Osthole was observed to decrease the protein expression of X-chromosome-encoded IAP, c-IAP1, c-IAP2 and Survivin, and increase Smac expression in a dose-dependent manner. Furthermore, it was noted that Osthole or Embelin alone increased the expression of BAX, caspase-3, caspase-9, cleaved caspase-3 and cleaved caspase-9, and decreased Bcl-2 levels following treatment. Osthole and Embelin combination treatment had a synergistic effect on the regulation of these proteins. In conclusion, our study demonstrated that Osthole inhibited proliferation and induced the apoptosis of lung cancer cells via IAP family proteins in a dose-dependent manner. Osthole enhances the antitumor effect of Embelin, indicating that combination of Osthole and Embelin has potential clinical significance in the treatment of NSCLC. PMID:27895730

  3. Gliotoxin Inhibits Proliferation and Induces Apoptosis in Colorectal Cancer Cells

    PubMed Central

    Chen, Junxiong; Wang, Chenliang; Lan, Wenjian; Huang, Chunying; Lin, Mengmeng; Wang, Zhongyang; Liang, Wanling; Iwamoto, Aikichi; Yang, Xiangling; Liu, Huanliang

    2015-01-01

    The discovery of new bioactive compounds from marine natural sources is very important in pharmacological research. Here we developed a Wnt responsive luciferase reporter assay to screen small molecule inhibitors of cancer associated constitutive Wnt signaling pathway. We identified that gliotoxin (GTX) and some of its analogues, the secondary metabolites from marine fungus Neosartorya pseufofischeri, acted as inhibitors of the Wnt signaling pathway. In addition, we found that GTX downregulated the β-catenin levels in colorectal cancer cells with inactivating mutations of adenomatous polyposis coli (APC) or activating mutations of β-catenin. Furthermore, we demonstrated that GTX induced growth inhibition and apoptosis in multiple colorectal cancer cell lines with mutations of the Wnt signaling pathway. Together, we illustrated a practical approach to identify small-molecule inhibitors of the Wnt signaling pathway and our study indicated that GTX has therapeutic potential for the prevention or treatment of Wnt dependent cancers and other Wnt related diseases. PMID:26445050

  4. Glucocorticoid Induced Leucine Zipper inhibits apoptosis of cardiomyocytes by doxorubicin

    SciTech Connect

    Aguilar, David; Strom, Joshua; Chen, Qin M.

    2014-04-01

    Doxorubicin (Dox) is an indispensable chemotherapeutic agent for the treatment of various forms of neoplasia such as lung, breast, ovarian, and bladder cancers. Cardiotoxicity is a major concern for patients receiving Dox therapy. Previous work from our laboratory indicated that glucocorticoids (GCs) alleviate Dox-induced apoptosis in cardiomyocytes. Here we have found Glucocorticoid-Induced Leucine Zipper (GILZ) to be a mediator of GC-induced cytoprotection. GILZ was found to be induced in cardiomyocytes by GC treatment. Knocking down of GILZ using siRNA resulted in cancelation of GC-induced cytoprotection against apoptosis by Dox treatment. Overexpressing GILZ by transfection was able to protect cells from apoptosis induced by Dox as measured by caspase activation, Annexin V binding and morphologic changes. Western blot analyses indicate that GILZ overexpression prevented cytochrome c release from mitochondria and cleavage of caspase-3. When bcl-2 family proteins were examined, we found that GILZ overexpression causes induction of the pro-survival protein Bcl-xL. Since siRNA against Bcl-xL reverses GC induced cytoprotection, Bcl-xL induction represents an important event in GILZ-induced cytoprotection. Our data suggest that GILZ functions as a cytoprotective gene in cardiomyocytes. - Highlights: • Corticosteroids act as a cytoprotective agent in cardiomyocytes • Corticosteroids induce GILZ expression in cardiomyocytes • Elevated GILZ results in resistance against apoptosis induced by doxorubicin • GILZ induces Bcl-xL protein without inducing Bcl-xL mRNA.

  5. Resveratrol inhibits TIGAR to promote ROS induced apoptosis and autophagy.

    PubMed

    Kumar, Bhupender; Iqbal, Mohammad Askandar; Singh, Rajnish Kumar; Bamezai, Rameshwar N K

    2015-11-01

    Resveratrol has been shown to exhibit its anti-cancer effect through a variety of mechanisms. Here, TIGAR (TP53-Induced Glycolysis and Apoptosis Regulator) was identified as an important target of resveratrol for exhibiting ROS-dependent-consequences on apoptosis and autophagy. Resveratrol treatment decreased TIGAR protein irrespective of cell line used. Down-regulated TIGAR protein triggered a drop in reduced-glutathione levels which resulted in sustained ROS, responsible for apoptosis and autophagy. Over-expression and silencing experiments demonstrated the importance of TIGAR in affecting the ROS-dependent anti-cancer effects of resveratrol. Resveratrol treated cells exhibited autophagy to escape apoptosis, however, chloroquine treatment along with resveratrol, blocked protective autophagy and facilitated apoptosis. Collectively, results unravel the effects of resveratrol on TIGAR in mediating its ROS dependent influence and suggest a better combination therapy of resveratrol and chloroquine for probable cancer treatment.

  6. Calmodulin inhibition contributes to sensitize TRAIL-induced apoptosis in human lung cancer H1299 cells.

    PubMed

    Hwang, Mi-kyung; Min, Yong Ki; Kim, Seong Hwan

    2009-12-01

    Tumor necrosis factor related apoptosis-inducing ligand (TRAIL) preferentially triggers apoptosis in tumor cells versus normal cells. However, TRAIL alone is not effective in treating TRAIL-resistant tumors. We evaluated the effect of 180 enzyme inhibitors on TRAIL-induced apoptosis in human lung cancer H1299 cells, and found fluphenazine-N-2-chloroethane (a calmodulin (CaM) antagonist) sensitized TRAIL-induced apoptosis. Interestingly, in the presence of TRAIL, it increased caspase-8 binding to the Fas-associated death domain (FADD), but decreased binding of FADD-like interleukin-1beta-converting enzyme inhibitory proteins (FLIPs). Additionally, its combination with TRAIL inhibited Akt phosphorylation. These results were consistently observed in cells treated with CaM siRNA. We suggested the blockade of CaM could sensitize lung cancer cells to TRAIL-induced apoptosis in at least 2 ways: (i) it can activate death-inducing signaling complex mediated apoptosis by inhibiting TRAIL-induced binding of FLIP and TRAIL-enhanced binding of caspase-8 to FADD; (ii) it can inhibit Akt phosphorylation, consequently leading to decreased expression of anti-apoptotic molecules such as FLIP and members of the inhibitor of apoptosis protein family. This study suggests the combination of CaM antagonists with TRAIL may have the therapeutic potential to overcome the resistance of lung cancers to apoptosis.

  7. Resveratrol inhibits the hydrogen dioxide-induced apoptosis via Sirt 1 activation in osteoblast cells.

    PubMed

    He, Na; Zhu, Xuewei; He, Wei; Zhao, Shiwei; Zhao, Weiyan; Zhu, Chunlei

    2015-01-01

    Sirt 1 plays a critical role in stress responses. We determined the deregulation of Sirt 1 activity, p53 acetylation, Bcl-2 expression, and mitochondria-dependent apoptosis in mouse osteoblast MC3T3-E1 cells which were exposed to H2O2. And then we investigated the protective role of Sirt 1 activator, Resveratrol (RSV), against the H2O2-induced apoptosis. Results demonstrated that Sirt 1 and Bcl-2 were inhibited, whereas p53 acetylation, Bax, and caspase 9 were promoted by H2O2, as was aggravated by the Sirt 1 inhibitor, EX-527. Instead, RSV inhibited the H2O2-induced both p53 acetylation and the caspase 9 activation, whereas ameliorated the H2O2-induced Bcl-2 inhibition and apoptosis. In conclusion, Sirt 1 was downregulated during the H2O2-induced apoptosis in MC3T3-E1 cells. And the chemical activation of Sirt 1 inhibited the H2O2-induced apoptosis via the downregulation of p53 acetylation. Our results suggest that Sirt 1 upregulation appears to be an important strategy to inhibit the oxidative stress-induced apoptosis.

  8. Inhibition of nitric oxide-induced apoptosis by nicotine in oral epithelial cells.

    PubMed

    Banerjee, Abhijit G; Gopalakrishnan, Velliyur K; Vishwanatha, Jamboor K

    2007-11-01

    Development of oral cancer is clearly linked to the usage of smokeless tobacco. The molecular mechanisms involved in this process are however not well understood. Toward this goal, we investigated the effect of smokeless tobacco exposure on apoptosis of oral epithelial cells. Exposure of oral epithelial cells to smokeless tobacco extract (STE) induces apoptosis in a dose-dependent manner, until a threshold level of nicotine is achieved upon which apoptosis is inhibited. 1 mM of nicotine is able to inhibit apoptosis significantly induced by STE in these oral cells. Exposure of cells to nicotine alone has no effect on apoptosis, but nicotine inhibits apoptosis induced by other agents present in STE. In this study we show that, the anti-apoptotic action of nicotine is specifically associated with down-regulation of nitric oxide (NO) production. Using specific inducers of NO, we have demonstrated that inhibition of apoptosis by nicotine is through down-regulation of NO production. Further, we observed that nicotine clearly acts as a sink of NO radicals, shown using peroxynitrite generator (SIN-1) in conjunction or absence of radical scavengers. Nicotine thus causes most damage in transformed epithelial cells as depicted by accumulation of nitrotyrosine in a 3-NT ELISA assay. Inhibition of apoptosis is a hallmark in tumor progression and propels development of cancer. It may further result in functional loss of apoptotic effector mechanisms in the transformed cells. Thus, our data clearly indicates that inhibition of NO-induced apoptosis by nicotine may lead to tobacco-induced oral carcinogenesis, and implies careful development of modalities in tobacco cessation programs.

  9. Effects of ceramide inhibition on radiation-induced apoptosis in human leukemia MOLT-4 cells.

    PubMed

    Takahashi, Eriko; Inanami, Osamu; Asanuma, Taketoshi; Kuwabara, Mikinori

    2006-03-01

    In the present study, using inhibitors of ceramide synthase (fumonisin B1), ketosphinganine synthetase (L-cycloserine), acid sphingomyelinase (D609 and desipramine) and neutral sphingomyelinase (GW4869), the role of ceramide in X-ray-induced apoptosis was investigated in MOLT-4 cells. The diacylglycerol kinase (DGK) assay showed that the intracellular concentration of ceramide increased time-dependently after X irradiation of cells, and this radiation-induced accumulation of ceramide did not occur prior to the appearance of apoptotic cells. Treatment with D609 significantly inhibited radiation-induced apoptosis, but did not inhibit the increase of intracellular ceramide. Treatment with desipramine or GW4869 prevented neither radiation-induced apoptosis nor the induced increase of ceramide. On the other hand, fumonisin B1 and L-cycloserine had no effect on the radiation-induced induction of apoptosis, in spite of significant inhibition of the radiation-induced ceramide. From these results, it was suggested that the increase of the intracellular concentration of ceramide was not essential for radiation-induced apoptosis in MOLT-4 cells.

  10. Xanthohumol inhibits Notch signaling and induces apoptosis in hepatocellular carcinoma.

    PubMed

    Kunnimalaiyaan, Selvi; Sokolowski, Kevin M; Balamurugan, Mariappan; Gamblin, T Clark; Kunnimalaiyaan, Muthusamy

    2015-01-01

    Despite improvement in therapeutic strategies, median survival in advanced hepatocellular carcinoma (HCC) remains less than one year. Therefore, molecularly targeted compounds with less toxic profiles are needed. Xanthohumol (XN), a prenylated chalcone has been shown to have anti-proliferative effects in various cancers types in vitro. XN treatment in healthy mice and humans yielded favorable pharmacokinetics and bioavailability. Therefore, we determined to study the effects of XN and understand the mechanism of its action in HCC. The effects of XN on a panel of HCC cell lines were assessed for cell viability, colony forming ability, and cellular proliferation. Cell lysates were analyzed for pro-apoptotic (c-PARP and cleaved caspase-3) and anti-apoptotic markers (survivin, cyclin D1, and Mcl-1). XN concentrations of 5 μM and above significantly reduced the cell viability, colony forming ability and also confluency of all four HCC cell lines studied. Furthermore, growth suppression due to apoptosis was evidenced by increased expression of pro-apoptotic and reduced expression of anti-apoptotic proteins. Importantly, XN treatment inhibited the Notch signaling pathway as evidenced by the decrease in the expression of Notch1 and HES-1 proteins. Ectopic expression of Notch1 in HCC cells reverses the anti-proliferative effect of XN as evidenced by reduced growth suppression compared to control. Taken together these results suggested that XN mediated growth suppression is appeared to be mediated by the inhibition of the Notch signaling pathway. Therefore, our findings warrants further studies on XN as a potential agent for the treatment for HCC.

  11. Xanthohumol Inhibits Notch Signaling and Induces Apoptosis in Hepatocellular Carcinoma

    PubMed Central

    Kunnimalaiyaan, Selvi; Gamblin, T. Clark; Kunnimalaiyaan, Muthusamy

    2015-01-01

    Despite improvement in therapeutic strategies, median survival in advanced hepatocellular carcinoma (HCC) remains less than one year. Therefore, molecularly targeted compounds with less toxic profiles are needed. Xanthohumol (XN), a prenylated chalcone has been shown to have anti-proliferative effects in various cancers types in vitro. XN treatment in healthy mice and humans yielded favorable pharmacokinetics and bioavailability. Therefore, we determined to study the effects of XN and understand the mechanism of its action in HCC. The effects of XN on a panel of HCC cell lines were assessed for cell viability, colony forming ability, and cellular proliferation. Cell lysates were analyzed for pro-apoptotic (c-PARP and cleaved caspase-3) and anti-apoptotic markers (survivin, cyclin D1, and Mcl-1). XN concentrations of 5μM and above significantly reduced the cell viability, colony forming ability and also confluency of all four HCC cell lines studied. Furthermore, growth suppression due to apoptosis was evidenced by increased expression of pro-apoptotic and reduced expression of anti-apoptotic proteins. Importantly, XN treatment inhibited the Notch signaling pathway as evidenced by the decrease in the expression of Notch1 and HES-1 proteins. Ectopic expression of Notch1 in HCC cells reverses the anti-proliferative effect of XN as evidenced by reduced growth suppression compared to control. Taken together these results suggested that XN mediated growth suppression is appeared to be mediated by the inhibition of the Notch signaling pathway. Therefore, our findings warrants further studies on XN as a potential agent for the treatment for HCC. PMID:26011160

  12. Inhibition of protein geranylgeranylation induces apoptosis in synovial fibroblasts.

    PubMed

    Connor, Alison M; Berger, Stuart; Narendran, Aru; Keystone, Edward C

    2006-01-01

    Statins, competitive inhibitors of hydroxymethylglutaryl-CoA reductase, have recently been shown to have a therapeutic effect in rheumatoid arthritis (RA). In RA, synovial fibroblasts in the synovial lining, are believed to be particularly important in the pathogenesis of disease because they recruit leukocytes into the synovium and secrete angiogenesis-promoting molecules and proteases that degrade extracellular matrix. In this study, we show a marked reduction in RA synovial fibroblast survival through the induction of apoptosis when the cells were cultured with statins. Simvastatin was more effective in RA synovial fibroblasts than atorvastatin, and both statins were more potent on tumor necrosis factor-alpha-induced cells. In contrast, in osteoarthritis synovial fibroblasts, neither the statin nor the activation state of the cell contributed to the efficacy of apoptosis induction. Viability of statin-treated cells could be rescued by geranylgeraniol but not by farnesol, suggesting a requirement for a geranylgeranylated protein for synovial fibroblast survival. Phase partitioning experiments confirmed that in the presence of statin, geranylgeranylated proteins are redistributed to the cytoplasm. siRNA experiments demonstrated a role for Rac1 in synovial fibroblast survival. Western blotting showed that the activated phosphorylated form of Akt, a protein previously implicated in RA synovial fibroblast survival, was decreased by about 75%. The results presented in this study lend further support to the importance of elevated pAkt levels to RA synovial fibroblast survival and suggest that statins might have a beneficial role in reducing the aberrant pAkt levels in patients with RA. The results may also partly explain the therapeutic effect of atorvastatin in patients with RA.

  13. Novel quinolone CHM-1 induces apoptosis and inhibits metastasis in a human osterogenic sarcoma cell line.

    PubMed

    Hsu, Shu-Chun; Yang, Jai-Sing; Kuo, Chao-Lin; Lo, Chyi; Lin, Jing-Pin; Hsia, Te-Chun; Lin, Jen-Jyh; Lai, Kuang-Chi; Kuo, Hsiu-Maan; Huang, Li-Jiau; Kuo, Sheng-Chu; Wood, W Gibson; Chung, Jing-Gung

    2009-12-01

    Novel 2-phenyl-4-quinolone compounds have potent cytotoxic effects on different human cancer cell lines. In this study, we examined anticancer activity and mechanisms of 20-fluoro-6,7-methylenedioxy-2-phenyl-4-quinolone (CHM-1) in human osterogenic sarcoma U-2 OS cells. CHM-1-induced apoptosis was determined by flow cytometric analysis, DAPI staining, Comet assay, and caspase inhibitors. CHM-1-inhibited cell migration and invasion was assessed by a wound healing assay, gelatin zymography, and a Transwell assay. The mechanisms of CHM-1 effects on apoptosis and metastasis signaling pathways were studied using Western blotting and gene expression. CHM-1 induced G2/M arrest and apoptosis at an IC(50) (3 microM) in U-2 OS cells and caspase-3, -8, and -9 were activated. Caspase inhibitors increased cell viability after exposure to CHM-1. CHM-1-induced apoptosis was associated with enhanced ROS generation, DNA damage, decreased DeltaPsi(m) levels, and promotion of mitochondrial cytochrome c release. CHM-1 stimulated mRNA expression of caspase-3, -8, and -9, AIF, and Endo G. In addition, CHM-1 inhibited cell metastasis at a low concentration (<3 microM). CHM-1 inhibited the cell metastasis through the inhibition of MMP-2, -7, and -9. CHM-1 also decreased the levels of MAPK signaling pathways before leading to the inhibition of MMPs. In summary, CHM-1 is a potent inducer of apoptosis, which plays a role in the anticancer activity of CHM-1.

  14. Low-power laser irradiation inhibits Aβ25-35-induced cell apoptosis through Akt activation

    NASA Astrophysics Data System (ADS)

    Zhang, Zhigang; Tang, Yonghong

    2009-08-01

    Low-power laser irradiation (LPLI) can modulate various cellular processes such as proliferation, differentiation and apoptosis. Recently, LPLI has been applied to moderate Alzheimer's disease (AD), but the underlying mechanism remains unknown. The protective role of LPLI against the amyloid beta peptide (Aβ), a major constituent of AD plaques, has not been studied. PI3K/Akt pathway is extremely important in protecting cells from apoptosis caused by diverse stress stimuli. However, whether LPLI can inhibit Aβ-induced apoptosis through Akt activation is still unclear. In current study, using FRET (fluorescence resonance energy transfer) technique, we investigated the activity of Akt in response to LPLI treatment. B kinase activity reporter (BKAR), a recombinant FRET probe of Akt, was utilized to dynamically detect the activation of Akt after LPLI treatment. The results show that LPLI promoted the activation of Akt. Moreover, LPLI inhibits apoptosis induced by Aβ25-35 and the apoptosis inhibition can be abolished by wortmannin, a specific inhibitor of PI3K/Akt. Taken together, these results suggest that LPLI can inhibit Aβ25-35-induced cell apoptosis through Akt activation.

  15. Baicalin inhibits colistin sulfate-induced apoptosis of PC12 cells.

    PubMed

    Jiang, Hong; Lv, Pengfei; Li, Jichang; Wang, Hongjun; Zhou, Tiezhong; Liu, Yingzi; Lin, Wei

    2013-10-05

    Baicalin, a type of flavonoid extracted from the dried root of Scutellaria baicalensis georgi, has been shown to effectively inhibit cell apoptosis. Therefore, we assumed that baicalin would suppress co-listin sulfate-induced neuronal apoptosis. PC12 cells exposed to colistin sulfate (62.5-500 μg/mL) for 24 hours resulted in PC12 cell apoptosis. In addition, caspase-3 activity, lactate dehydrogenase level and free radical content increased in a dose-dependent manner. Subsequently, PC12 cells were pretreated with baicalin (25, 50 and 100 μg/mL), and exposed to 125 μg/mL colistin sulfate. Cell morphology markedly changed, and cell viability increased. Moreover, caspase-3 activity, tate dehydrogenase level and free radical content decreased. Results indicated that baicalin inhi-bited colistin sulfate-induced PC12 cell apoptosis by suppressing free radical injury, and reducing caspase-3 activity and lactate dehydrogenase activity.

  16. Inhibition of proteasome activity is involved in cobalt-induced apoptosis of human alveolar macrophages.

    PubMed

    Araya, Jun; Maruyama, Muneharu; Inoue, Akira; Fujita, Tadashi; Kawahara, Junko; Sassa, Kazuhiko; Hayashi, Ryuji; Kawagishi, Yukio; Yamashita, Naohiro; Sugiyama, Eiji; Kobayashi, Masashi

    2002-10-01

    Inhalation of particulate cobalt has been known to induce interstitial lung disease. There is growing evidence that apoptosis plays a crucial role in physiological and pathological settings and that the ubiquitin-proteasome system is involved in the regulation of apoptosis. Cadmium, the same transitional heavy metal as cobalt, has been reported to accumulate ubiquitinated proteins in neuronal cells. On the basis of these findings, we hypothesized that cobalt would induce apoptosis in the lung by disturbance of the ubiquitin-proteasome pathway. To evaluate this, we exposed U-937 cells and human alveolar macrophages (AMs) to cobalt chloride (CoCl(2)) and examined their apoptosis by DNA fragmentation assay, 4',6-diamidino-2'-phenylindol dihydrochloride staining, and Western blot analysis. CoCl(2) induced apoptosis and accumulated ubiquitinated proteins. Exposure to CoCl(2) inhibited proteasome activity in U-937 cells. Cobalt-induced apoptosis was mediated via mitochondrial pathway because CoCl(2) released cytochrome c from mitochondria. These results suggest that cobalt-induced apoptosis of AMs may be one of the mechanisms for cobalt-induced lung injury and that the accumulation of ubiquitinated proteins might be involved in this apoptotic process.

  17. Gambogic acid induces apoptosis in diffuse large B-cell lymphoma cells via inducing proteasome inhibition.

    PubMed

    Shi, Xianping; Lan, Xiaoying; Chen, Xin; Zhao, Chong; Li, Xiaofen; Liu, Shouting; Huang, Hongbiao; Liu, Ningning; Zang, Dan; Liao, Yuning; Zhang, Peiquan; Wang, Xuejun; Liu, Jinbao

    2015-04-08

    Resistance to chemotherapy is a great challenge to improving the survival of patients with diffuse large B-cell lymphoma (DLBCL), especially those with activated B-cell-like DLBCL (ABC-DLBCL). Therefore it is urgent to search for novel agents for the treatment of DLBCL. Gambogic acid (GA), a small molecule derived from Chinese herb gamboges, has been approved for Phase II clinical trial for cancer therapy by Chinese FDA. In the present study, we investigated the effect of GA on cell survival and apoptosis in DLBCL cells including both GCB- and ABC-DLBCL cells. We found that GA induced growth inhibition and apoptosis of both GCB- and ABC-DLBCL cells in vitro and in vivo, which is associated with proteasome malfunction. These findings provide significant pre-clinical evidence for potential usage of GA in DLBCL therapy particularly in ABC-DLBCL treatment.

  18. Inhibition of autophagy ameliorates atherogenic inflammation by augmenting apigenin-induced macrophage apoptosis.

    PubMed

    Wang, Qun; Zeng, Ping; Liu, Yuanliang; Wen, Ge; Fu, Xiuqiong; Sun, Xuegang

    2015-07-01

    Increasing evidences showed that the survival of macrophages promotes atherogenesis. Macrophage apoptosis in the early phase of atherosclerotic process negatively regulates the progression of atherosclerotic lesions. We demonstrated that a natural anti-oxidant apigenin could ameliorate atherogenesis in ApoE(-/-) mice. It reduced the number of foam cells and decreased the serum levels of tumor necrosis factor α, interleukin 1β (IL-1β) and IL-6. Our results showed that oxidized low-density lipoprotein (oxLDL) led to the secretion of pro-inflammatory cytokines. Apigenin-induced apoptosis and downregulated the secretion of TNF-α, IL-6 and IL-1β. It is further supported by the use of zVAD, a pan-caspase inhibitor, demonstrating that apigenin lowered cytokine profile through induction of macrophage apoptosis. Moreover, apigenin-induced Atg5/Atg7-dependent autophagy in macrophages pretreated with oxLDL. Results illustrated that autophagy inhibition increased apigenin-induced apoptosis through activation of Bax. The present findings suggest that oxLDL maintained the survival of macrophages and activated the secretion of pro-inflammatory cytokines to initiate atherosclerosis. Apigenin-induced apoptosis of lipid-laden macrophages and resolved inflammation to ameliorate atherosclerosis. In conclusion, combination of apigenin with autophagy inhibition may be a promising strategy to induce foam cell apoptosis and subdue atherogenic cytokines.

  19. Corosolic acid inhibits the proliferation of osteosarcoma cells by inducing apoptosis

    PubMed Central

    Jia, Yong; Yuan, Hua; Shan, Shouqin; Xu, Gang; Yu, Jie; Zhao, Chenguang; Mou, Xiang

    2016-01-01

    Corosolic acid (CRA), a pentacyclic triterpene isolated from medicinal herbs, has been reported to exhibit anticancer properties in several cancers. However, the anticancer activity of CRA in osteosarcoma cells is still unclear. In the present study, the inhibitory effect of CRA in osteosarcoma MG-63 cells was investigated, and the results revealed that CRA significantly inhibited the viability of MG-63 cells in a dose- and time-dependent manner. A typical apoptotic hallmark such as DNA ladder was detected by agarose gel electrophoresis following treatment with CRA. Further experiments demonstrated that CRA induced apoptosis of MG-63 cells by flow cytometry using propidium iodide and annexin V staining. In addition, it was observed that the apoptosis of MG-63 cells induced by CRA was closely associated with activation of caspase-3 and caspase-9, loss of mitochondrial membrane potential, and release of cytochrome c from mitochondria, suggesting that CRA may trigger the activation of the mitochondria-mediated apoptosis pathway. In addition, the inhibition of caspase activity attenuated the CRA-induced apoptosis of MG-63 cells, which further confirmed the role of the mitochondrial pathway in CRA-induced apoptosis. These results indicated that CRA could induce the apoptosis of osteosarcoma cells through activating the mitochondrial pathway, which provides an evidence that CRA may be a useful chemotherapeutic agent for osteosarcoma. PMID:27895790

  20. Oncogenic Ras promotes butyrate-induced apoptosis through inhibition of gelsolin expression.

    PubMed

    Klampfer, Lidija; Huang, Jie; Sasazuki, Takehiko; Shirasawa, Senji; Augenlicht, Leonard

    2004-08-27

    Activation of Ras promotes oncogenesis by altering a multiple of cellular processes, such as cell cycle progression, differentiation, and apoptosis. Oncogenic Ras can either promote or inhibit apoptosis, depending on the cell type and the nature of the apoptotic stimuli. The response of normal and transformed colonic epithelial cells to the short chain fatty acid butyrate, a physiological regulator of epithelial cell maturation, is also divergent: normal epithelial cells proliferate, and transformed cells undergo apoptosis in response to butyrate. To investigate the role of k-ras mutations in butyrate-induced apoptosis, we utilized HCT116 cells, which harbor an oncogenic k-ras mutation and two isogenic clones with targeted inactivation of the mutant k-ras allele, Hkh2, and Hke-3. We demonstrated that the targeted deletion of the mutant k-ras allele is sufficient to protect epithelial cells from butyrate-induced apoptosis. Consistent with this, we showed that apigenin, a dietary flavonoid that has been shown to inhibit Ras signaling and to reverse transformation of cancer cell lines, prevented butyrate-induced apoptosis in HCT116 cells. To investigate the mechanism whereby activated k-ras sensitizes colonic cells to butyrate, we performed a genome-wide analysis of Ras target genes in the isogenic cell lines HCT116, Hkh2, and Hke-3. The gene exhibiting the greatest down-regulation by the activating k-ras mutation was gelsolin, an actin-binding protein whose expression is frequently reduced or absent in colorectal cancer cell lines and primary tumors. We demonstrated that silencing of gelsolin expression by small interfering RNA sensitized cells to butyrate-induced apoptosis through amplification of the activation of caspase-9 and caspase-7. These data therefore demonstrate that gelsolin protects cells from butyrate-induced apoptosis and suggest that Ras promotes apoptosis, at least in part, through its ability to down-regulate the expression of gelsolin.

  1. cAMP prevents TNF-induced apoptosis through inhibiting DISC complex formation in rat hepatocytes.

    PubMed

    Bhattacharjee, Rajesh; Xiang, Wenpei; Wang, Yinna; Zhang, Xiaoying; Billiar, Timothy R

    2012-06-22

    Tumor necrosis factor α (TNF) is a pleiotropic proinflammatory cytokine that plays a role in immunity and the control of cell proliferation, cell differentiation, and apoptosis. The pleiotropic nature of TNF is due to the formation of different signaling complexes upon the binding of TNF to its receptor, TNF receptor type 1 (TNFR1). TNF induces apoptosis in various mammalian cells when the cells are co-treated with a transcription inhibitor like actinomycin D (ActD). When TNFR1 is activated, it recruits an adaptor protein, TNF receptor-associated protein with death domain (TRADD), through its cytoplasmic death effector domain (DED). TRADD, in turn, recruits other signaling proteins, including TNF receptor-associated protein 2 (TRAF2) and receptor-associated protein kinase (RIPK) 1, to form a complex. Subsequently, this complex combines with FADD and procaspase-8, converts into a death-inducing signaling complex (DISC) to induce apoptosis. Cyclic AMP (cAMP) is a second messenger that regulates various cellular processes such as cell proliferation, gene expression, and apoptosis. cAMP analogues are reported to act as anti-apoptotic agents in various cell types, including hepatocytes. We found that a cAMP analogue, dibutyryl cAMP (db-cAMP), inhibits TNF+ActD-induced apoptosis in rat hepatocytes. The protein kinase A (PKA) inhibitor KT-5720 reverses this inhibitory effect of cAMP on apoptosis. Cytoprotection by cAMP involves down-regulation of various apoptotic signal regulators like TRADD and FADD and inhibition of caspase-8 and caspase-3 cleavage. We also found that cAMP exerts its affect at the proximal level of TNF signaling by inhibiting the formation of the DISC complex upon the binding of TNF to TNFR1. In conclusion, our study shows that cAMP prevents TNF+ActD-induced apoptosis in rat hepatocytes by inhibiting DISC complex formation.

  2. Inhibition of COX-2/PGE2 cascade ameliorates cisplatin-induced mesangial cell apoptosis

    PubMed Central

    Yu, Xiaowen; Yang, Yunwen; Yuan, Hui; Wu, Meng; Li, Shuzhen; Gong, Wei; Yu, Jing; Xia, Weiwei; Zhang, Yue; Ding, Guixia; Huang, Songming; Jia, Zhanjun; Zhang, Aihua

    2017-01-01

    Cisplatin is one of the most potent cytotoxic drug for the treatment of many types of cancer. However, the side effects on normal tissues, particularly on the kidney, greatly limited its use in clinic. Emerging evidence demonstrated that cisplatin could directly cause mesangial cell apoptosis, while the potential mechanism is still elusive. Here we examined the contribution of COX-2 in cisplatin-induced mesangial cell apoptosis. Firstly, we found cisplatin induced cell apoptosis in mesangial cells shown by increased number of apoptotic cells in parallel with the upregulation of Bax and the downregulation of Bcl-2. Interestingly, cisplatin-induced cell apoptosis was accompanied by an upregulation of COX-2 at both mRNA and protein levels in dose- and time-dependent manners. Importantly, inhibition of COX-2 via a specific COX-2 inhibitor celecoxib markedly blocked cisplatin-induced mesangial cell apoptosis as evidenced by the decreased number of apoptotic cells, blocked increments of cleaved caspase-3 and Bax, and reversed Bcl-2 downregulation. Meanwhile, cisplatin-induced PGE2 production was markedly blocked by the treatment of celecoxib. In conclusion, this study indicated that COX-2/PGE2 cascade activation mediated cisplatin-induced mesangial cell apoptosis. The findings not only offered new insights into the understanding of cisplatin nephrotoxicity but also provided the therapeutic potential by targeting COX-2/PGE2 cascade in treating cisplatin-induced kidney injury. PMID:28386348

  3. Valsartan protects HK-2 cells from contrast media-induced apoptosis by inhibiting endoplasmic reticulum stress.

    PubMed

    Peng, Ping-An; Wang, Le; Ma, Qian; Xin, Yi; Zhang, Ou; Han, Hong-Ya; Liu, Xiao-Li; Ji, Qing-Wei; Zhou, Yu-Jie; Zhao, Ying-Xin

    2015-12-01

    Contrast-induced acute kidney injury (CI-AKI) is associated with increasing in-hospital and long-term adverse clinical outcomes in high-risk patients undergoing percutaneous coronary intervention (PCI). Contrast media (CM)-induced renal tubular cell apoptosis is reported to participate in this process by activating endoplasmic reticulum (ER) stress. An angiotensin II type 1 receptor (AT1R) antagonist can alleviate ER stress-induced renal apoptosis in streptozotocin (STZ)-induced diabetic mice and can reduce CM-induced renal apoptosis by reducing oxidative stress and reversing the enhancement of bax mRNA and the reduction of bcl-2 mRNA, but the effect of the AT1R blocker on ER stress in the pathogenesis of CI-AKI is still unknown. In this study, we explored the effect of valsartan on meglumine diatrizoate-induced human renal tubular cell apoptosis by measuring changes in ER stress-related biomarkers. The results showed that meglumine diatrizoate caused significant cell apoptosis by up-regulating the expression of ER stress markers, including glucose-regulated protein 78 (GRP78), activating transcription factor 4 (ATF4), CCAAT/enhancer-binding protein-homologous protein (CHOP) and caspase 12, in a time- and dose-dependent manner, which could be alleviated by preincubation with valsartan. In conclusion, valsartan had a potential nephroprotective effect on meglumine diatrizoate-induced renal cell apoptosis by inhibiting ER stress.

  4. Deoxynivalenol inhibits proliferation and induces apoptosis in human umbilical vein endothelial cells.

    PubMed

    Deng, Chao; Ji, Changyun; Qin, Weisen; Cao, Xifeng; Zhong, Jialian; Li, Yugu; Srinivas, Swaminath; Feng, Youjun; Deng, Xianbo

    2016-04-01

    Deoxynivalenol (DON) is a stable mycotoxins found in cereals infected by certain fungal species and causes adverse health effects in animals and human such as vomiting, diarrhea and reproductive toxicity. In this study, we investigated the toxic and apoptotic effects of DON in human umbilical vein endothelial cells (HUVECs), a good model for studying inflammation. The results show that DON significantly inhibited the viability of HUVECs. DON could also inhibit the proliferation of HUVECs through G2/M phase arrest in cell cycle progression. Moreover, oxidative stress induced by DON was indicated by observations of increased levels of reactive oxygen species (ROS). In addition, DON also causes mitochondrial damage by decreasing the mitochondrial membrane potential and inducing apoptosis by up-regulation of apoptosis-related genes like caspase-3, caspase-9, and Bax genes, and down-regulation of Bcl-2 gene. These results together suggest that DON could induce cell cycle arrest, oxidative stress, and apoptosis in HUVECs.

  5. Sorafenib inhibition of Mcl-1 accelerates ATRA induced apoptosis in differentiation responsive AML cells

    PubMed Central

    Wang, Rui; Xia, Lijuan; Gabrilove, Janice; Waxman, Samuel; Jing, Yongkui

    2015-01-01

    Purpose All trans retinoic acid (ATRA) is successful in treating acute promyelocytic leukemia (APL) by inducing terminal differentiation-mediated cell death, but it has limited activity in non-APL acute myeloid leukemia (AML). We aim to improve ATRA therapy of AML by enhancing apoptosis through repression of the anti-apoptotic proteins Bcl-2 and Mcl-1. Experimental Design APL and AML cell lines, as well as primary AML samples, were used to explore the mechanisms regulating differentiation and apoptosis during ATRA treatment. Stable transfection and gene silencing with siRNA were used to identify the key factors that inhibit apoptosis during induction of differentiation and drugs that accelerate apoptosis. Results In differentiation responsive AML cells, ATRA treatment induces long-lasting repression of Bcl-2 while first up-modulating and then reducing the Mcl-1 level. The Mcl-1 level appears to serve as a gatekeeper between differentiation and apoptosis. During differentiation induction, activation of MEK/ERK and PI3K/Akt pathways by ATRA leads to activation of p90RSK and inactivation of glycogen synthase kinase 3β (GSK3β), which increase Mcl-1 levels by increasing its translation and stability. Sorafenib blocks ATRA-induced Mcl-1 increase by reversing p90RSK activation and GSK3β inactivation, maintains the repressed Bcl-2 level, and enhances ATRA induced apoptosis in non-APL AML cell lines and in primary AML cells. Conclusion Inhibition of Mcl-1 is required for apoptosis induction in ATRA differentiation responsive AML cells. ATRA and Sorafenib can be developed as a novel drug combination therapy for AML patients because this drug combination augments apoptosis by inhibiting Bcl-2 and Mcl-1. PMID:26459180

  6. Phenylethanoid glycosides from Cistanches salsa inhibit apoptosis induced by 1-methyl-4-phenylpyridinium ion in neurons.

    PubMed

    Tian, Xue-Fei; Pu, Xiao-Ping

    2005-02-10

    In our study we investigated the neuroprotective effects of phenylethanoid glycosides (PhGs) from Cistanches salsa on 1-methyl-4-phenylpyridinium ion (MPP(+))-induced apoptosis in cerebellar granule neurons (CGNs). CGNs were treated with 100 microM MPP(+) for 24h to induce apoptosis, simultaneously CGNs were incubated with PhGs at 10, 20 and 40 microg/ml, respectively. In addition CGNs were pretreated with PhGs at 20 microg/ml for 6, 12, 24 h, respectively, and then treated with 100 microM MPP(+) for 24 h. 3-(4,5-Dimethylthiazol-2-ylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay revealed that the treatment of CGNs with PhGs inhibited the decrease of cell viability induced by MPP(+). The activation of caspase-3 and caspase-8 was induced by MPP(+) in apoptosis. The caspase-3 and caspase-8 fluorogenic assays showed that the treatments of CGNs with PhGs efficiently suppressed the activation of caspase-3 and caspase-8 induced by MPP(+). It is concluded that PhGs can prevent the MPP(+)-induced apoptosis in CGNs and exert its anti-apoptosis effect by inhibiting caspase-3 and caspase-8 activities.

  7. Low-power laser irradiation inhibits amyloid beta-induced cell apoptosis

    NASA Astrophysics Data System (ADS)

    Zhang, Heng; Wu, Shengnan

    2011-03-01

    The deposition and accumulation of amyloid-β-peptide (Aβ) in the brain are considered a pathological hallmark of Alzheimer's disease(AD). Apoptosis is a contributing pathophysiological mechanism of AD. Low-power laser irradiation (LPLI), a non-damage physical therapy, which has been used clinically for decades of years, is shown to promote cell proliferation and prevent apoptosis. Recently, low-power laser irradiation (LPLI) has been applied to moderate AD. In this study, Rat pheochromocytoma (PC12) cells were treated with amyloid beta 25-35 (Aβ25-35) for induction of apoptosis before LPLI treatment. We measured cell viability with CCK-8 according to the manufacture's protocol, the cell viability assays show that low fluence of LPLI (2 J/cm2 ) could inhibit the cells apoptosis. Then using statistical analysis of proportion of apoptotic cells by flow cytometry based on Annexin V-FITC/PI, the assays also reveal that low fluence of LPLI (2 J/cm2 ) could inhibit the Aβ-induced cell apoptosis. Taken together, we demonstrated that low fluence of LPLI (2 J/cm2 ) could inhibit the Aβ-induced cell apoptosis, these results directly point to a therapeutic strategy for the treatment of AD through LPLI.

  8. A novel small molecule, LAS-0811, inhibits alcohol-induced apoptosis in VL-17A cells.

    PubMed

    Kim, Tae-Hun; Venugopal, Senthil K; Zhu, Ming; Wang, Si-Si; Lau, Derick; Lam, Kit S; Clemens, Dahn L; Zern, Mark A

    2009-02-20

    One of the pathways by which alcohol induces hepatocyte apoptosis is via oxidative stress. We screened several chemically-synthesized small molecules and found LAS-0811, which inhibits oxidative stress. In this study, we elucidated its role in inhibiting alcohol-induced apoptosis in hepatocyte-like VL-17A cells. VL-17A cells were pre-incubated with LAS-0811, followed by ethanol incubation. Ethanol-induced reactive oxygen species and apoptosis were significantly inhibited in LAS-0811 pre-treated cells. VL-17A cells were transfected with a reporter (ARE/TK-GFP) plasmid containing green fluorescent protein (GFP) as a reporter gene and the anti-oxidant response element as the promoter. LAS-0811 pre-treatment significantly induced the GFP expression compared to the cells treated with ethanol alone. LAS-0811 induced the activation of nrf2 and enhanced the expression and activity of glutathione peroxidase, one of the downstream targets of nrf2. The results indicate that LAS-0811 protects VL-17A cells against ethanol-induced oxidative stress and apoptosis at least in part via nrf2 activation.

  9. Blockade of store-operated calcium entry alleviates ethanol-induced hepatotoxicity via inhibiting apoptosis

    SciTech Connect

    Cui, Ruibing; Yan, Lihui; Luo, Zheng; Guo, Xiaolan; Yan, Ming

    2015-08-15

    Extracellular Ca{sup 2+} influx has been suggested to play a role in ethanol-induced hepatocyte apoptosis and necrosis. Previous studies indicated that store-operated Ca{sup 2+} entry (SOCE) was involved in liver injury induced by ethanol in HepG2 cells. However, the mechanisms underlying liver injury caused by SOCE remain unclear. We aimed to investigate the effects and mechanism of SOCE inhibition on liver injury induced by ethanol in BRL cells and Sprague–Dawley rats. Our data demonstrated that ethanol (0–400 mM) dose-dependently increased hepatocyte injury and 100 mM ethanol significantly upregulated the mRNA and protein expression of SOC for at least 72 h in BRL cells. Blockade of SOCE by pharmacological inhibitors and sh-RNA knockdown of STIM1 and Orai1 attenuated intracellular Ca{sup 2+} overload, restored the mitochondrial membrane potential (MMP), decreased cytochrome C release and inhibited ethanol-induced apoptosis. STIM1 and Orai1 expression was greater in ethanol-treated than control rats, and the SOCE inhibitor corosolic acid ameliorated the histopathological findings and alanine transaminase and aspartate transaminase activity as well as decreased cytochrome C release and inhibited alcohol-induced cell apoptosis. These findings suggest that SOCE blockade could alleviate alcohol-induced hepatotoxicity via inhibiting apoptosis. SOCE might be a useful therapeutic target in alcoholic liver diseases. - Highlights: • Blockade of SOCE alleviated overload of Ca{sup 2+} and hepatotoxicity after ethanol application. • Blockade of SOCE inhibited mitochondrial apoptosis after ethanol application. • SOCE might be a useful therapeutic target in alcoholic liver diseases.

  10. Inhibition of vascular peroxidase alleviates cardiac dysfunction and apoptosis induced by ischemia-reperfusion.

    PubMed

    Li, Ting-Ting; Zhang, Yi-Shuai; He, Lan; Liu, Bin; Shi, Rui-Zheng; Zhang, Guo-Gang; Peng, Jun

    2012-07-01

    Myeloperoxidase (MPO) is involved in myocardial ischemia-reperfusion (IR) injury and vascular peroxidase (VPO) is a newly identified isoform of MPO. This study was conducted to explore whether VPO is involved in IR-induced cardiac dysfunction and apoptosis. In a rat Langendorff model of myocardial IR, the cardiac function parameters (left ventricular pressure and the maximum derivatives of left ventricular pressure and coronary flow), creatine kinase (CK) activity, apoptosis, VPO1 activity were measured. In a cell (rat-heart-derived H9c2 cells) model of hypoxia-reoxygenation (HR), apoptosis, VPO activity, and VPO1 mRNA expression were examined. In isolated heart, IR caused a marked decrease in cardiac function and a significant increase in apoptosis, CK, and VPO activity. These effects were attenuated by pharmacologic inhibition of VPO. In vitro, pharmacologic inhibition of VPO activity or silencing of VPO1 expression significantly suppressed HR-induced cellular apoptosis. Our results suggest that increased VPO activity contributes to IR-induced cardiac dysfunction and inhibition of VPO activity may have the potential clinical value in protecting the myocardium against IR injury.

  11. Effects of inducing or inhibiting apoptosis on Sindbis virus replication in mosquito cells.

    PubMed

    Wang, Hua; Blair, Carol D; Olson, Ken E; Clem, Rollie J

    2008-11-01

    Sindbis virus (SINV) is a mosquito-borne virus in the genus Alphavirus, family Togaviridae. Like most alphaviruses, SINVs exhibit lytic infection (apoptosis) in many mammalian cell types, but are generally thought to cause persistent infection with only moderate cytopathic effects in mosquito cells. However, there have been several reports of apoptotic-like cell death in mosquitoes infected with alphaviruses or flaviviruses. Given that apoptosis has been shown to be an antiviral response in other systems, we have constructed recombinant SINVs that express either pro-apoptotic or anti-apoptotic genes in order to test the effects of inducing or inhibiting apoptosis on SINV replication in mosquito cells. Recombinant SINVs expressing the pro-apoptotic genes reaper (rpr) from Drosophila or michelob_x (mx) from Aedes aegypti caused extensive apoptosis in cells from the mosquito cell line C6/36, thus changing the normal persistent infection observed with SINV to a lytic infection. Although the infected cells underwent apoptosis, high levels of virus replication were still observed during the initial infection. However, virus production subsequently decreased compared with persistently infected cells, which continued to produce high levels of virus over the next several days. Infection of C6/36 cells with SINV expressing the baculovirus caspase inhibitor P35 inhibited actinomycin D-induced caspase activity and protected infected cells from actinomycin D-induced apoptosis, but had no observable effect on virus replication. This study is the first to test directly whether inducing or inhibiting apoptosis affects arbovirus replication in mosquito cells.

  12. Inhibition of NF-kappaB/Rel induces apoptosis of murine B cells.

    PubMed Central

    Wu, M; Lee, H; Bellas, R E; Schauer, S L; Arsura, M; Katz, D; FitzGerald, M J; Rothstein, T L; Sherr, D H; Sonenshein, G E

    1996-01-01

    Apoptosis of the WEHI 231 immature B cell lymphoma line following membrane interaction with an antibody against the surface IgM chains (anti-IgM) is preceded by dramatic changes in Nuclear Factor-kappaB (NF-kappaB)/ Rel binding activities. An early transient increase in NF-kappaB/Rel binding is followed by a significant decrease in intensity below basal levels. Here we have explored the role of these changes in Rel-related factors in B cell apoptosis. Treatment of WEH1 231 cells with N-tosyl-L-phenylalanine chloromethyl ketone (TPCK), a protease inhibitor which prevents degradation of the inhibitor of NF-kappaB (IkappaB)-alpha, or with low doses of pyrrolidinedithiocarbamate (PDTC) selectively inhibited NF-kappaB/Rel factor binding and induced apoptosis. Bcl-XL expression protected WEHI 231 cells from apoptosis induced by these agents. Microinjection of WEHI 231 cells with either IkappaB-alpha-GST protein or a c-Rel affinity-purified antibody induced apoptosis. Ectopic c-Rel expression ablated apoptosis induced by TPCK or anti-IgM. Treatment of BALENLM 17 and A20 B lymphoma cells or normal murine splenic B lymphocytes with either TPCK or PDTC also resulted in apoptosis. These findings indicate that the drop in NF-kappaB/Rel binding following anti-IgM treatment activates apoptosis of WEHI 231 cells; furthermore, they implicate the NF-kappaB/Rel family in control of apoptosis of normal and transformed B cells. Images PMID:8887559

  13. VCC-1 over-expression inhibits cisplatin-induced apoptosis in HepG2 cells

    SciTech Connect

    Zhou, Zhitao; Lu, Xiao; Zhu, Ping; Zhu, Wei; Mu, Xia; Qu, Rongmei; Li, Ming

    2012-04-06

    Highlights: Black-Right-Pointing-Pointer VCC-1 is hypothesized to be associated with carcinogenesis. Black-Right-Pointing-Pointer Levels of VCC-1 are increased significantly in HCC. Black-Right-Pointing-Pointer Over-expression of VCC-1 could promotes cellular proliferation rate. Black-Right-Pointing-Pointer Over-expression of VCC-1 inhibit the cisplatin-provoked apoptosis in HepG2 cells. Black-Right-Pointing-Pointer VCC-1 plays an important role in control the tumor growth and apoptosis. -- Abstract: Vascular endothelial growth factor-correlated chemokine 1 (VCC-1), a recently described chemokine, is hypothesized to be associated with carcinogenesis. However, the molecular mechanisms by which aberrant VCC-1 expression determines poor outcomes of cancers are unknown. In this study, we found that VCC-1 was highly expressed in hepatocellular carcinoma (HCC) tissue. It was also associated with proliferation of HepG2 cells, and inhibition of cisplatin-induced apoptosis of HepG2 cells. Conversely, down-regulation of VCC-1 in HepG2 cells increased cisplatin-induced apoptosis of HepG2 cells. In summary, these results suggest that VCC-1 is involved in cisplatin-induced apoptosis of HepG2 cells, and also provides some evidence for VCC-1 as a potential cellular target for chemotherapy.

  14. Alpha B-Crystallin Protects Rat Articular Chondrocytes against Casein Kinase II Inhibition-Induced Apoptosis

    PubMed Central

    Rho, Jee Hyun; Lee, Sang Yeob; Yoo, Seung Hee; Kim, Hye Young; Chung, Won Tae; Yoo, Young Hyun

    2016-01-01

    Although alpha (α)B-crystallin is expressed in articular chondrocytes, little is known about its role in these cells. Protein kinase casein kinase 2 (CK2) inhibition induces articular chondrocyte death. The present study examines whether αB-crystallin exerts anti-apoptotic activity in articular chondrocytes. Primary rat articular chondrocytes were isolated from knee joint slices. Cells were treated with CK2 inhibitors with or without αB-crystallin siRNA. To examine whether the silencing of αB-crystallin sensitizes rat articular chondrocytes to CK2 inhibition-induced apoptosis, we assessed apoptosis by performing viability assays, mitochondrial membrane potential measurements, flow cytometry, nuclear morphology observations, and western blot analysis. To investigate the mechanism by which αB-crystallin modulates the extent of CK2 inhibition-mediated chondrocyte death, we utilized confocal microscopy to observe the subcellular location of αB-crystallin and its phosphorylated forms and performed a co-immunoprecipitation assay to observe the interaction between αB-crystallin and CK2. Immunochemistry was employed to examine αB-crystallin expression in cartilage obtained from rats with experimentally induced osteoarthritis (OA). Our results demonstrated that silencing of αB-crystallin sensitized rat articular chondrocytes to CK2 inhibitor-induced apoptosis. Furthermore, CK2 inhibition modulated the expression and subcellular localization of αB-crystallin and its phosphorylated forms and dissociated αB-crystallin from CK2. The population of rat articular chondrocytes expressing αB-crystallin and its phosphorylated forms was reduced in an experimentally induced rat model of OA. In summary, αB-crystallin protects rat articular chondrocytes against CK2 inhibition-induced apoptosis. αB-crystallin may represent a suitable target for pharmacological interventions to prevent OA. PMID:27851782

  15. 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

  16. Biguanides sensitize leukemia cells to ABT-737-induced apoptosis by inhibiting mitochondrial electron transport.

    PubMed

    Velez, Juliana; Pan, Rongqing; Lee, Jason T C; Enciso, Leonardo; Suarez, Marta; Duque, Jorge Eduardo; Jaramillo, Daniel; Lopez, Catalina; Morales, Ludis; Bornmann, William; Konopleva, Marina; Krystal, Gerald; Andreeff, Michael; Samudio, Ismael

    2016-08-09

    Metformin displays antileukemic effects partly due to activation of AMPK and subsequent inhibition of mTOR signaling. Nevertheless, Metformin also inhibits mitochondrial electron transport at complex I in an AMPK-independent manner, Here we report that Metformin and rotenone inhibit mitochondrial electron transport and increase triglyceride levels in leukemia cell lines, suggesting impairment of fatty acid oxidation (FAO). We also report that, like other FAO inhibitors, both agents and the related biguanide, Phenformin, increase sensitivity to apoptosis induction by the bcl-2 inhibitor ABT-737 supporting the notion that electron transport antagonizes activation of the intrinsic apoptosis pathway in leukemia cells. Both biguanides and rotenone induce superoxide generation in leukemia cells, indicating that oxidative damage may sensitize toABT-737 induced apoptosis. In addition, we demonstrate that Metformin sensitizes leukemia cells to the oligomerization of Bak, suggesting that the observed synergy with ABT-737 is mediated, at least in part, by enhanced outer mitochondrial membrane permeabilization. Notably, Phenformin was at least 10-fold more potent than Metformin in abrogating electron transport and increasing sensitivity to ABT-737, suggesting that this agent may be better suited for targeting hematological malignancies. Taken together, our results suggest that inhibition of mitochondrial metabolism by Metformin or Phenformin is associated with increased leukemia cell susceptibility to induction of intrinsic apoptosis, and provide a rationale for clinical studies exploring the efficacy of combining biguanides with the orally bioavailable derivative of ABT-737, Venetoclax.

  17. PI3K Inhibition Enhances Doxorubicin-Induced Apoptosis in Sarcoma Cells

    PubMed Central

    Marklein, Diana; Graab, Ulrike; Naumann, Ivonne; Yan, Tiandong; Ridzewski, Rosalie; Nitzki, Frauke; Rosenberger, Albert; Dittmann, Kai; Wienands, Jürgen; Wojnowski, Leszek; Fulda, Simone; Hahn, Heidi

    2012-01-01

    We searched for a drug capable of sensitization of sarcoma cells to doxorubicin (DOX). We report that the dual PI3K/mTOR inhibitor PI103 enhances the efficacy of DOX in several sarcoma cell lines and interacts with DOX in the induction of apoptosis. PI103 decreased the expression of MDR1 and MRP1, which resulted in DOX accumulation. However, the enhancement of DOX-induced apoptosis was unrelated to DOX accumulation. Neither did it involve inhibition of mTOR. Instead, the combination treatment of DOX plus PI103 activated Bax, the mitochondrial apoptosis pathway, and caspase 3. Caspase 3 activation was also observed in xenografts of sarcoma cells in nude mice upon combination of DOX with the specific PI3K inhibitor GDC-0941. Although the increase in apoptosis did not further impact on tumor growth when compared to the efficient growth inhibition by GDC-0941 alone, these findings suggest that inhibition of PI3K may improve DOX-induced proapoptotic effects in sarcoma. Taken together with similar recent studies of neuroblastoma- and glioblastoma-derived cells, PI3K inhibition seems to be a more general option to sensitize tumor cells to anthracyclines. PMID:23300809

  18. Biguanides sensitize leukemia cells to ABT-737-induced apoptosis by inhibiting mitochondrial electron transport

    PubMed Central

    Velez, Juliana; Pan, Rongqing; Lee, Jason T.C.; Enciso, Leonardo; Suarez, Marta; Duque, Jorge Eduardo; Jaramillo, Daniel; Lopez, Catalina; Morales, Ludis; Bornmann, William; Konopleva, Marina; Krystal, Gerald; Andreeff, Michael; Samudio, Ismael

    2016-01-01

    Metformin displays antileukemic effects partly due to activation of AMPK and subsequent inhibition of mTOR signaling. Nevertheless, Metformin also inhibits mitochondrial electron transport at complex I in an AMPK-independent manner, Here we report that Metformin and rotenone inhibit mitochondrial electron transport and increase triglyceride levels in leukemia cell lines, suggesting impairment of fatty acid oxidation (FAO). We also report that, like other FAO inhibitors, both agents and the related biguanide, Phenformin, increase sensitivity to apoptosis induction by the bcl-2 inhibitor ABT-737 supporting the notion that electron transport antagonizes activation of the intrinsic apoptosis pathway in leukemia cells. Both biguanides and rotenone induce superoxide generation in leukemia cells, indicating that oxidative damage may sensitize toABT-737 induced apoptosis. In addition, we demonstrate that Metformin sensitizes leukemia cells to the oligomerization of Bak, suggesting that the observed synergy with ABT-737 is mediated, at least in part, by enhanced outer mitochondrial membrane permeabilization. Notably, Phenformin was at least 10-fold more potent than Metformin in abrogating electron transport and increasing sensitivity to ABT-737, suggesting that this agent may be better suited for targeting hematological malignancies. Taken together, our results suggest that inhibition of mitochondrial metabolism by Metformin or Phenformin is associated with increased leukemia cell susceptibility to induction of intrinsic apoptosis, and provide a rationale for clinical studies exploring the efficacy of combining biguanides with the orally bioavailable derivative of ABT-737, Venetoclax. PMID:27283492

  19. Panax quinquefolium saponin attenuates cardiomyocyte apoptosis induced by thapsigargin through inhibition of endoplasmic reticulum stress

    PubMed Central

    Liu, Mi; Xue, Mei; Wang, Xiao-Reng; Tao, Tian-Qi; Xu, Fei-Fei; Liu, Xiu-Hua; Shi, Da-Zhuo

    2015-01-01

    Background Endoplasmic reticulum (ER) stress-related apoptosis is involved in the pathophysiology of many cardiovascular diseases, and Panax quinquefolium saponin (PQS) is able to inhibit excessive ER stress-related apoptosis of cardiomyocytes following hypoxia/reoxygenation and myocardial infarction. However, the pathway by which PQS inhibits the ER stress-related apoptosis is not well understood. To further investigate the protective effect of PQS against ER stress-related apoptosis, primary cultured cardiomyocytes were stimulated with thapsigargin (TG), which is widely used to model cellular ER stress, and it could induce apoptotic cell death in sufficient concentration. Methods Primary cultured cardiomyocytes from neonatal rats were exposed to TG (1 µmol/L) treatment for 24 h, following PQS pre-treatment (160 µg/mL) for 24 h or pre-treatment with small interfering RNA directed against protein kinase-like endoplasmic reticulum kinase (Si-PERK) for 6 h. The viability and apoptosis rate of cardiomyocytes were detected by cell counting kit-8 and flow cytometry respectively. ER stress-related protein expression, such as glucose-regulated protein 78 (GRP78), calreticulin, PERK, eukaryotic translation initiation factor 2α (eIF2α), activating transcription factor 4 (ATF4), and C/EBP homologous protein (CHOP) were assayed by western blotting. Results Both PQS pre-treatment and PERK knockdown remarkably inhibited the cardiomyocyte apoptosis induced by TG, increased cell viability, decreased phosphorylation of both PERK and eIF2α, and decreased protein levels of both ATF4 and CHOP. There was no statistically significant difference between PQS pre-treatment and PERK knockdown in the cardioprotective effect. Conclusions Our data indicate that the PERK-eIF2α-ATF4-CHOP pathway of ER stress is involved in the apoptosis induced by TG, and PQS might prevent TG-induced cardiomyocyte apoptosis through a mechanism involving the suppression of this pathway. These findings

  20. Inhibition of 12-lipoxygenase during baicalein-induced human lung nonsmall carcinoma H460 cell apoptosis.

    PubMed

    Leung, Henry W C; Yang, W H; Lai, M Y; Lin, C J; Lee, H Z

    2007-03-01

    Baicalein is known as a 12-lipoxygenase (12-LOX) inhibitor. The 12-LOX is found to be involved in the progression of human cancers and the inhibitor of 12-LOX offers a target for the prevention cancer. We demonstrated the inhibitory effect of baicalein on the gene and protein expression of 12-LOX in H460 human lung nonsmall carcinoma cell line. Treatment of baicalein inhibited the growth of H460 cells in a dose-dependent manner. Following 24h exposure to 50muM baicalein, cell cycle analysis revealed an increase in the cell population in S-phase. During the S-phase arrest, baicalein decreased the protein levels of cdk1 and cyclin B1, which are the regulating proteins of S-phase transition to G2/M-phase, in this study. Furthermore, baicalein induced the most of H460 cell apoptosis after treatment for 48h. H460 cells formed vesicles and apoptotic body, and then floated after treatment with baicalein. Baicalein-induced H460 cell apoptosis was confirmed by DNA condensation and fragmentation. Baicalein-induced apoptosis were also accompanied by decreasing in Bcl-2 and proform of caspase-3 and increasing p53 and Bax protein levels. Pretreatment with a specific caspase-3 inhibitor, Ac-DEVD-CHO, partially reduced baicalein-induced cell death, indicating baicalein induces apoptosis is partially dependent on caspase-3 pathway in H460 cells. These data suggest that baicalein, a 12-LOX inhibitor, inhibits the proliferation of H460 cells via S-phase arrest and induces apoptosis in association with the regulation of molecules in the cell cycle and apoptosis-related proteins.

  1. cAMP prevents TNF-induced apoptosis through inhibiting DISC complex formation in rat hepatocytes

    SciTech Connect

    Bhattacharjee, Rajesh; Xiang, Wenpei; Wang, Yinna; Zhang, Xiaoying

    2012-06-22

    Highlights: Black-Right-Pointing-Pointer cAMP blocks cell death induced by TNF and actinomycin D in cultured hepatocytes. Black-Right-Pointing-Pointer cAMP blocks NF-{kappa}B activation induced by TNF and actinomycin D. Black-Right-Pointing-Pointer cAMP blocks DISC formation following TNF and actinomycin D exposure. Black-Right-Pointing-Pointer cAMP blocks TNF signaling at a proximal step. -- Abstract: Tumor necrosis factor {alpha} (TNF) is a pleiotropic proinflammatory cytokine that plays a role in immunity and the control of cell proliferation, cell differentiation, and apoptosis. The pleiotropic nature of TNF is due to the formation of different signaling complexes upon the binding of TNF to its receptor, TNF receptor type 1 (TNFR1). TNF induces apoptosis in various mammalian cells when the cells are co-treated with a transcription inhibitor like actinomycin D (ActD). When TNFR1 is activated, it recruits an adaptor protein, TNF receptor-associated protein with death domain (TRADD), through its cytoplasmic death effector domain (DED). TRADD, in turn, recruits other signaling proteins, including TNF receptor-associated protein 2 (TRAF2) and receptor-associated protein kinase (RIPK) 1, to form a complex. Subsequently, this complex combines with FADD and procaspase-8, converts into a death-inducing signaling complex (DISC) to induce apoptosis. Cyclic AMP (cAMP) is a second messenger that regulates various cellular processes such as cell proliferation, gene expression, and apoptosis. cAMP analogues are reported to act as anti-apoptotic agents in various cell types, including hepatocytes. We found that a cAMP analogue, dibutyryl cAMP (db-cAMP), inhibits TNF + ActD-induced apoptosis in rat hepatocytes. The protein kinase A (PKA) inhibitor KT-5720 reverses this inhibitory effect of cAMP on apoptosis. Cytoprotection by cAMP involves down-regulation of various apoptotic signal regulators like TRADD and FADD and inhibition of caspase-8 and caspase-3 cleavage. We also found

  2. Lysophosphatidic Acid Inhibits Apoptosis Induced by Cisplatin in Cervical Cancer Cells

    PubMed Central

    Sui, Yanxia; Yang, Ya; Wang, Ji; Li, Yi; Ma, Hongbing; Cai, Hui; Liu, Xiaoping; Zhang, Yong; Wang, Shufeng; Li, Zongfang; Zhang, Xiaozhi; Wang, Jiansheng; Liu, Rui; Yan, Yanli; Xue, Chaofan; Shi, Xiaowei; Tan, Li; Ren, Juan

    2015-01-01

    Cervical cancer is the second most common cause of cancer death in women worldwide. Lysophosphatidic acid (LPA) level has been found significantly increased in the serum of patients with ovarian, cervical, and colon cancers. LPA level in cervical cancer patients is significantly higher than in healthy controls. LPA receptors were found highly expressed in cervical cancer cells, suggesting LPA may play a role in the development of cervical cancer. The aim of this study is to investigate the effect of LPA on the apoptosis induced by cisplatin (DDP) in cervical cancer cell line and the underlying changes in signaling pathways. Our study found that cisplatin induced apoptosis of Hela cell through inhibiting expression of Bcl-2, upregulating the expression of Bax, Fas-L, and the enzyme activity of caspase-3 (p < 0.05); LPA significantly provided protection against the apoptosis induced by cisplatin by inhibiting the above alterations in apoptotic factor caused by cisplatin (p < 0.05). Moreover, PI3K/AKT pathway was found to be important for the LPA antiapoptosis effect, and administration of PI3K/AKT partially reversed the LPA-mediated protection against cisplatin-induced apoptosis (p < 0.05). These findings have shed new lights on the LPA bioactivity in cervical cancer cells and pointed to a possible sensitization scheme through combined administration of PI3K inhibitor and cisplatin for better treatment of cervical cancer patients, especially those with elevated LPA levels. PMID:26366416

  3. Bergamot juice extract inhibits proliferation by inducing apoptosis in human colon cancer cells.

    PubMed

    Visalli, Giuseppa; Ferlazzo, Nadia; Cirmi, Santa; Campiglia, Pietro; Gangemi, Sebastiano; Di Pietro, Angela; Calapai, Gioacchino; Navarra, Michele

    2014-01-01

    Colorectal cancer (CRC) is a leading cause of cancer mortality in the industrialized world, second to lung cancer. A lot of evidences highlight that a diet rich in fruits and vegetables may reduce the risk of some types of cancer including CRC. In this study we demonstrate that Citrus bergamia juice extracts (BJe) reduces CRC cell growth by multiple mechanisms. Low BJe concentrations inhibit MAPKs pathway and alter apoptosis-related proteins, that in turn induce cell cycle arrest and apoptosis in HT-29 cells. Instead, high concentrations of BJe induce oxidative stress causing DNA damage. Our study highlights the role of BJe as modulator of cell apoptosis in CRC cells and strengthens our previous hypothesis that the flavonoid fraction of bergamot juice may play a role as anti-cancer drug.

  4. Targeting autophagy potentiates chemotherapy-induced apoptosis and proliferation inhibition in hepatocarcinoma cells.

    PubMed

    Guo, Xian-Ling; Li, Ding; Hu, Fei; Song, Jian-Rui; Zhang, Shan-Shan; Deng, Wei-Jie; Sun, Kai; Zhao, Qiu-Dong; Xie, Xu-Qin; Song, Yu-Jiao; Wu, Meng-Chao; Wei, Li-Xin

    2012-07-28

    Induction of cell death and inhibition of cell growth are the main targets of cancer therapy. Here we evaluated the role of autophagy on chemoresistance of human hepatocarcinoma (HCC) cell lines, focusing on its crosstalk with cell apoptosis and proliferation. In this study, a chemotherapeutic agent (cisplatin or 5FU) induced the formation of autophagosomes in three human HCC cell lines and upregulated the expression of autophagy protein LC3-II. Inhibition of autophagy by 3-methyladenine or si-beclin 1 increased chemotherapy-induced apoptosis in HCC cells. Meanwhile, increased damage of the mitochondrial membrane potential was also observed in HCC cells when autophagy was inhibited. Furthermore, inhibition of autophagy reduced clone formation and impaired cell growth of HCC cells when treated with chemotherapy. Co-administration of an autophagy inhibitor (chloroquine) and chemotherapy significantly inhibited tumor growth in a mouse xenograft tumor model, with greater extent of apoptosis and impaired proliferation of tumor cells. This study suggests that autophagy is a potential novel target to improve therapy efficiency of conventional chemotherapeutics towards HCC.

  5. Benzyl-isothiocyanate Induces Apoptosis and Inhibits Migration and Invasion of Hepatocellular Carcinoma Cells in vitro

    PubMed Central

    Zhu, Mingyue; Li, Wei; Dong, Xu; Chen, Yi; Lu, Yan; Lin, Bo; Guo, Junli; Li, Mengsen

    2017-01-01

    Despite consideration of benzyl isothiocyanate(BITC) is applied to prevention and therapeutic of cancer, the role of BITC in inducing apoptosis, and inhibiting migration and invasion of hepatocellular carcinoma(HCC) cells is still unclear. In this study, we aim to explore the effects of BITC on the growth, migration and invasion of HCC cells in vitro. When human HCC cell lines, Bel 7402 and HLE, were treated with an optimal concentration of BITC for 48 hours, the results indicated that BITC inhibits growth and promotes apoptosis of HCC cells; BITC has a significant inhibitory effect on the migration and invasion of HCC cells. BITC stimulated expression of caspase-3/8 and PARP-1, and suppressed expression of survivin, MMP2/9 and CXCR4. BITC also inhibited the enzymatic activities of MMP2 and MMP9. Altogether, BITC was able to induce apoptosis and suppress the invasive and migratory abilities of Bel 7402 and HLE cells. The role mechanism of BITC might involve an up-regulating the expression of apoptosis-related proteins and down-regulating the expression of metastasis-related proteins. BITC may be applied as a novel chemotherapy for HCC patients. PMID:28243328

  6. PI3K/AKT inhibition induces caspase-dependent apoptosis in HTLV-1-transformed cells.

    PubMed

    Jeong, Soo-Jin; Dasgupta, Arindam; Jung, Kyung-Jin; Um, Jee-Hyun; Burke, Aileen; Park, Hyeon Ung; Brady, John N

    2008-01-20

    The phosphatidylinositol-3-kinase (PI3K) and AKT (protein kinase B) signaling pathways play an important role in regulating cell cycle progression and cell survival. In previous studies, we demonstrated that AKT is activated in HTLV-1-transformed cells and that Tax activation of AKT is linked to p53 inhibition and cell survival. In the present study, we extend these observations to identify regulatory pathways affected by AKT in HTLV-1-transformed cells. We demonstrate that inhibition of AKT reduces the level of phosphorylated Bad, an important member of the pro-apoptotic family of proteins. Consistent with the decrease of phosphorylated Bad, cytochrome c is released from the mitochondria and caspase-9 is activated. Pretreatment of the cells with caspase-9 specific inhibitor z-LEHD-FMK or pan caspase inhibitor Ac-DEVD-CHO prevented LY294002-induced apoptosis. Of interest, p53 siRNA prevents LY294002-induced apoptosis in HTLV-1-transformed cells, suggesting that p53 reactivation is linked to apoptosis. In conclusion, the AKT pathway is involved in targeting multiple proteins which regulate caspase- and p53-dependent apoptosis in HTLV-1-transformed cells. Since AKT inhibitors simultaneously inhibit NF-kappaB and activate p53, these drugs should be promising candidates for HTLV-1-associated cancer therapy.

  7. Panax notoginseng saponins attenuates cisplatin-induced nephrotoxicity via inhibiting the mitochondrial pathway of apoptosis.

    PubMed

    Liu, Xinwen; Huang, Zhenguang; Zou, Xiaoqin; Yang, Yufang; Qiu, Yue; Wen, Yan

    2014-01-01

    The goal of this experiment was to investigate the protective effect and the molecular mechanism of Panax Notoginseng Saponins (PNS) on cisplatin-induced nephrotoxicity through mitochondrial pathway of apoptosis. The rats underwent intraperitoneal injection with a single dose of cisplatin, a subset of rats were also intraperitoneally injected with 31.35 mg/kg PNS once a day for 8 days. At day 1, 4 and 8 after exposure to cisplatin, the concentrations of blood urea nitrogen (BUN), serum creatinine (Scr) and urinary N-acetyl-β-D-Glucosaminidase (NAG) were determined using commercial kits. The pathological change of renal tissue were examined using H & E staining and transmission electron microscopy. The rate of apoptosis and the expression of Bcl-2 in rat renal tissue were detected by using TUNEL staining and Western bloting, respectively. And the expressions of Bax and caspases 9 were detected by immunnohistochemistry. The results showed that PNS significantly protected against cisplatin-induced nephrotoxicity, as evidenced by the decrease in concentration of blood BUN, Scr and urinary NAG, as well as the attenuation of renal histopathological damage. Furthermore, PNS reduced the rate of apoptosis, and the mechanism studies showed that PNS inhibited the expression of Bax and caspase 9, while increased the expression of Bcl-2. This study first demonstrated that PNS can protect against cisplatin-induced nephrotoxicity and reduce renal tissue apoptosis via inhibiting the mitochondrial pathway.

  8. Enhancement of taxol-induced apoptosis by inhibition of NF-κB with ursorlic acid

    NASA Astrophysics Data System (ADS)

    Li, Yunlong; Xing, Da

    2007-05-01

    Taxol is known to inhibit cell growth and triggers significant apoptosis in various cancer cells, and activation of proliferation factor NF-κB during Taxol-induced apoptosis is regarded as a main reason resulting in tumor cells resistance to Taxol. It has been found that ursorlic acid can inhibit the activation of NF-κB. In order to study whether ursorlic acid can enhance the Taxol-induced apoptosis, we use fluorescence resonance energy transfer (FRET) technique and probe SCAT3 to compare the difference of caspase-3 activation between Taxol alone and Taxol combined ursorlic acid. With laser scanning confocal microscopy, we find that ursorlic acid, a nontoxic food component, sensitizes ASTC-a-1 cells more efficiently to Taxol-induced apoptosis by advanced activation of caspase 3. The result also suggests that there would be a synergistic effect between Taxol and ursorlic acid, and the more detailed mechanism of synergistic effect needs to be clarified further, such as the correlations among NF-κB, Akt, caspase 8, which leads to the advanced activation of caspase 3 during combined treatment of Taxol and ursorlic acid. Moreover, this may be a new way to improve Taxol-dependent tumor therapy.

  9. Beauveria attenuates asthma by inhibiting inflammatory response and inducing lymphocytic cell apoptosis

    PubMed Central

    Zhang, Jingying; Zhou, Xianmei; Zhu, Jiping

    2016-01-01

    The present study aimed to investigate the role of beauveria (BEA) in asthma. We investigated the cytotoxic effect of BEA on the proliferation of inflammatory cells and secretion of inflammatory mediators both in-vitro and in-vivo. In in-vitro studies, BEA inhibited lymphocytic cell proliferation and the proliferation of lymphocytic cells induced by Phorbol-12-myristate-13-acetate (PMA). We used ELISA to test the effects of BEA on the secretion of inflammatory factors including tumor necrosis factor-alpha (TNF-α), interleukin-12 (IL-12) and interferon-gamma (IFN-γ). Flow cytometry was used to evaluate the influence of BEA on cell apoptosis. The effect of BEA on the cell numbers of eosinophils, lymphocytes, macrophages, neutrophils and other cells in mouse bronchoalveolar lavage fluid (BALF) was also evaluated. The expression of apoptosis related molecules Bax, Caspase-3 and Bcl-2 was examined by Western blotting analysis. Our results indicated that BEA played a protective role in asthma. BEA inhibited lymphocytic cell proliferation and secretion of inflammatory mediators. BEA promoted cell apoptosis, stimulated the expression of Bax and Caspase-3 and inhibited Bcl-2 protein expression in a dose-dependent manner. In in-vivo experiments, BEA reduced the cell number of eosinophils, lymphocytes, macrophages, neutrophils and other cells in mouse BALF. BEA inhibited secretion of inflammatory mediators, stimulated expression of Bax and Caspase-3, and inhibited expression of Bcl-2 in mouse lung tissue dose-dependently. All together, our results indicated that BEA could attenuate asthma by inhibiting inflammatory response and induce apoptosis of inflammatory cells. PMID:27801673

  10. Fluid shear stress inhibits TNF-α-induced osteoblast apoptosis via ERK5 signaling pathway.

    PubMed

    Bin, Geng; Cuifang, Wang; Bo, Zhang; Jing, Wang; Jin, Jiang; Xiaoyi, Tan; Cong, Chen; Yonggang, Chen; Liping, An; Jinglin, Ma; Yayi, Xia

    2015-10-09

    Fluid shear stress (FSS) is a potent mechanical stimulus and prevents cells from TNF-a-induced apoptosis. Recently, Extracellular-signal-regulated kinase 5 (ERK5) has been found to be involved in regulation of cell survival. However, little is known about the role of ERK5 signaling pathway in FSS-mediated anti-apoptotic effects in osteoblast. In this study, we show that FSS blocks TNF-a-induced apoptosis of MC3T3-E1 cells via ERK5 signaling pathway. We found that physiological FSS for 1 h significantly decreased TNF-α-induced MC3T3-E1 cells apoptosis. After inhibition of ERK5 activity by XMD8-92, a highly-selective inhibitor of ERK5 activity, the ability of FSS to inhibit TNF-α induced apoptosis was significantly decreased. Analysis of anti-apoptotic mechanisms indicated that exposure of MC3T3-E1 cells to FSS for 1 h increased phosphorylation of Bad and inhibited caspase-3 activity. After treatment with XMD8-92, phosphorylation of Bad by FSS was significantly blocked, but caspase-3 activity was increased. In summary, these findings indicated that FSS inhibits TNF-α-mediated signaling events in osteoblast by a mechanism dependent on activation of ERK5, and Bad is a crucial downstream target for ERK5. Those results implied that ERK5 signaling pathway play a crucial role in FSS-mediated anti-apoptotic effect in osteoblast. Thus, ERK5 signaling pathway may be a new drug treatment target of osteoporosis and related bone-wasting diseases.

  11. Arsenic trioxide induced indirect and direct inhibition of glutathione reductase leads to apoptosis in rat hepatocytes.

    PubMed

    Ray, Atish; Chatterjee, Sarmishtha; Mukherjee, Sandip; Bhattacharya, Shelley

    2014-06-01

    Glutathione reductase (GR) is an essential enzyme which maintains the reduced state of a cell. Therefore GR malfunction is closely associated with several disorders related to oxidative damage. The present study reports toxic manifestation of arsenic trioxide in respect of GR leading to apoptosis. Isolated rat hepatocytes exposed to arsenic trioxide were analyzed for GR expression and activity. Arsenic resulted in a time dependent inhibition of GR mediated by the superoxide anion. The cellular demand of functional enzyme is achieved by concomitant rise in gene expression. However, direct inhibition of GR by arsenic trioxide was also evident. Furthermore, arsenic induced free radical mediated inhibition of GR was found to be partially uncompetitive and associated with time dependent decrease in the substrate binding rate. Externalization of phosphatidylserine, nuclear degradation, apoptosis inducing factor leakage, apoptosome formation, caspase activation, DNA damage and break down of PARP suggest consequential induction of apoptosis due to inhibition of GR. The implication of GR was further established from the reduced rate of caspase activation in the arsenic trioxide treated cell, supplemented with complete and incomplete enzyme systems.

  12. Molecular Mechanisms of Luteolin Induced Growth Inhibition and Apoptosis of Human Osteosarcoma Cells

    PubMed Central

    Wang, Yonghong; Kong, Daliang; Wang, Xinwei; Dong, Xiaoxiong; Tao, Yingying; Gong, Haiyang

    2015-01-01

    Luteolin is a flavone in medicinal plants as well as some vegetables and spices. It is a natural anti-oxidant with less pro-oxidant potential but apparently with a better safety profile. The purpose of this study was to investigate the molecular mechanism of luteolin-mediated apoptosis of MG-63 human osteosarcoma cells. MTT assay kit was employed to evaluate the effects of luteolin on MG-63 cells proliferation. Then, we performed Annexin V-FITC/PI to analyze the apoptotic rate of the cells. Furthermore, the inhibitory effects of luteolin on the expressions of BCL-2, BAX, Caspase-3 and Survivin were detected by Western blotting. As expected, luteolin (0.5, 2.5, 12.5 µg/mL) inhibited the growth of MG-63 cells by inhibiting cell proliferation and inducing cell apoptosis. Western blotting demonstrated that luteolin (0.5, 2.5, 12.5 µg/mL) inhibited the expressions of BCL-2, Caspase-3 and Survivin, and promoted the expression of BAX in MG-63 cells with a concentration dependent way. Luteolin can inhibit osteosarcoma cell proliferation and induce apoptosis effectively in a dose dependent manner through down-regulating the expression of BCL-2, Caspase-3 and Survivin proteins levels and up-regulating the expression of BAX protein level. These findings indicated that luteolin may be used as a novel herbal medicine for the treatment of osteosarcoma. PMID:25901161

  13. Myricetin inhibits proliferation and induces apoptosis and cell cycle arrest in gastric cancer cells.

    PubMed

    Feng, Jianfang; Chen, Xiaonan; Wang, Yuanyuan; Du, Yuwen; Sun, Qianqian; Zang, Wenqiao; Zhao, Guoqiang

    2015-10-01

    Myricetin is a flavonoid that is abundant in fruits and vegetables and has protective effects against cancer and diabetes. However, the mechanism of action of myricetin against gastric cancer (GC) is not fully understood. We researched myricetin on the proliferation, apoptosis, and cell cycle in GC HGC-27 and SGC7901 cells, to explore the underlying mechanism of action. Cell Counting Kit (CCK)-8 assay, Western blotting, cell cycle analysis, and apoptosis assay were used to evaluate the effects of myricetin on cell proliferation, apoptosis, and the cell cycle. To analyze the binding properties of ribosomal S6 kinase 2 (RSK2) with myricetin, surface plasmon resonance (SPR) analysis was performed. CCK8 assay showed that myricetin inhibited GC cell proliferation. Flow cytometry analysis showed that myricetin induces apoptosis and cell cycle arrest in GC cells. Western blotting indicated that myricetin influenced apoptosis and cell cycle arrest of GC cells by regulating related proteins. SPR analysis showed strong binding affinity of RSK2 and myricetin. Myricetin bound to RSK2, leading to increased expression of Mad1, and contributed to inhibition of HGC-27 and SGC7901 cell proliferation. Our results suggest the therapeutic potential of myricetin in GC.

  14. Bacopa monnieri-Induced Protective Autophagy Inhibits Benzo[a]pyrene-Mediated Apoptosis.

    PubMed

    Das, Durgesh Nandini; Naik, Prajna Paramita; Nayak, Aditi; Panda, Prashanta Kumar; Mukhopadhyay, Subhadip; Sinha, Niharika; Bhutia, Sujit K

    2016-11-01

    Benzo[a]pyrene (B[a]P) is capable of inducing oxidative stress and cellular injuries leading to cell death and associates with a significant risk of cancer development. Prevention of B[a]P-induced cellular toxicity with herbal compound through regulation of mitochondrial oxidative stress might protect cell death and have therapeutic benefit to human health. In this study, we demonstrated the cytoprotective role of Bacopa monnieri (BM) against B[a]P-induced apoptosis through autophagy induction. Pretreatment with BM rescued the reduction in cell viability in B[a]P-treated human keratinocytes (HaCaT) cells indicating the cytoprotective potential of BM against B[a]P. Moreover, BM was found to inhibit B[a]P-mediated reactive oxygen species (ROS)-induced apoptosis activation in HaCaT cells. Furthermore, BM was found to preserve mitochondrial membrane potential and inhibited release of cytochrome c in B[a]P-treated HaCaT cells. Bacopa monnieri induced protective autophagy; we knocked down Beclin-1, and data showed that BM was unable to protect from B[a]P-induced mitochondrial ROS-mediated apoptosis in Beclin-1-deficient HaCaT cells. Moreover, we established that B[a]P-induced damaged mitochondria were found to colocalize and degraded within autolysosomes in order to protect HaCaT cells from mitochondrial injury. In conclusion, B[a]P-induced apoptosis was rescued by BM treatment and provided cytoprotection through Beclin-1-dependent autophagy activation. Copyright © 2016 John Wiley & Sons, Ltd.

  15. Inhibition of c-myc expression induces apoptosis of WEHI 231 murine B cells.

    PubMed Central

    Wu, M; Arsura, M; Bellas, R E; FitzGerald, M J; Lee, H; Schauer, S L; Sherr, D H; Sonenshein, G E

    1996-01-01

    Treatment of WEHI 231 immature B-lymphoma cells with an antibody against their surface immunoglobulin (anti-Ig) induces apoptosis and has been studied extensively as a model of B-cell tolerance. Anti-Ig treatment of exponentially growing WEHI 231 cells results in an early transient increase in c-myc expression that is followed by a decline to below basal levels; this decrease in c-myc expression immediately precedes the induction of cell death. Here we have modulated NF-kappaB/Rel factor activity, which regulates the rate of c-myc gene transcription, to determine whether the increase or decrease in c-Myc-levels mediates apoptosis in WEHI 231 cells. Addition of the serine/threonine protease inhibitor N-tosyl-L-phenylalanine chloromethyl ketone (TPCK), which blocks the normally rapid turnover of the specific inhibitor of NF-kappaB/Rel IkappaBalpha in these cells, caused a drop in Rel-related factor binding. TPCK treatment resulted in decreased c-myc expression, preventing the usual increase seen following anti-Ig treatment. Whereas inhibition of the induction of c-myc expression mediated by anti-Ig failed to block apoptosis, reduction of c-myc expression in exponentially growing WEHI 231 cells induced apoptosis even in the absence of anti-Ig treatment. In WEHI 231 clones ectopically expressing c-Myc, apoptosis induced by treatment with TPCK or anti-Ig was significantly diminished and cells continued to proliferate. Furthermore, apoptosis of WEHI 231 cells ensued following enhanced expression of Mad1, which has been found to reduce functional c-Myc levels. These results indicate that the decline in c-myc expression resulting from the drop in NF-kappaB/Rel binding leads to activation of apoptosis of WEHI 231 B cells. PMID:8756660

  16. α-Tomatine inhibits growth and induces apoptosis in HL-60 human myeloid leukemia cells.

    PubMed

    Huang, Huarong; Chen, Shaohua; Van Doren, Jeremiah; Li, Dongli; Farichon, Chelsea; He, Yan; Zhang, Qiuyan; Zhang, Kun; Conney, Allan H; Goodin, Susan; Du, Zhiyun; Zheng, Xi

    2015-06-01

    α‑Tomatine is a glycoalkaloid that occurs naturally in tomatoes (Lycopersicon esculentum). In the present study, the effects of α‑tomatine on human myeloid leukemia HL‑60 cells were investigated. Treatment of HL‑60 cells with α‑tomatine resulted in growth inhibition and apoptosis in a concentration‑dependent manner. Tomatidine, the aglycone of tomatine had little effect on the growth and apoptosis of HL‑60 cells. Growth inhibition and apoptosis induced by α‑tomatine in HL‑60 cells was partially abrogated by addition of cholesterol indicating that interactions between α‑tomatine and cell membrane‑associated cholesterol may be important in mediating the effect of α‑tomatine. Activation of nuclear factor‑κB by the phorbol ester, 12‑O‑tetradecanoylphorbol‑13‑acetate failed to prevent apoptosis in HL‑60 cells treated with α‑tomatine. In animal experiments, it was found that treatment of mice with α‑tomatine inhibited the growth of HL‑60 xenografts in vivo. Results from the present study indicated that α‑tomatine may have useful anti‑leukemia activities.

  17. α-tomatine inhibits growth and induces apoptosis in HL-60 human myeloid leukemia cells

    PubMed Central

    HUANG, HUARONG; CHEN, SHAOHUA; VAN DOREN, JEREMIAH; LI, DONGLI; FARICHON, CHELSEA; HE, YAN; ZHANG, QIUYAN; ZHANG, KUN; CONNEY, ALLAN H; GOODIN, SUSAN; DU, ZHIYUN; ZHENG, XI

    2015-01-01

    α-tomatine is a glycoalkaloid that occurs naturally in tomatoes (Lycopersicon esculentum). In the present study, the effects of α-tomatine on human myeloid leukemia HL-60 cells were investigated. Treatment of HL-60 cells with α-tomatine resulted in growth inhibition and apoptosis in a concentration-dependent manner. Tomatidine, the aglycone of tomatine had little effect on the growth and apoptosis of HL-60 cells. Growth inhibition and apoptosis induced by α-tomatine in HL-60 cells was partially abrogated by addition of cholesterol indicating that interactions between α-tomatine and cell membrane-associated cholesterol may be important in mediating the effect of α-tomatine. Activation of nuclear factor-κB by the phorbol ester, 12-O-tetradecanoylphorbol-13-acetate failed to prevent apoptosis in HL-60 cells treated with α-tomatine. In animal experiments, it was found that treatment of mice with α-tomatine inhibited the growth of HL-60 xenografts in vivo. Results from the present study indicated that α-tomatine may have useful anti-leukemia activities. PMID:25625536

  18. Lansoprazole induces apoptosis of breast cancer cells through inhibition of intracellular proton extrusion

    SciTech Connect

    Zhang, Shangrong; Wang, Yifan; Li, Shu Jie

    2014-06-13

    Highlights: • Lansoprazole (LPZ) induces cell apoptosis in breast cancer cells. • LPZ markedly inhibits intracellular proton extrusion. • LPZ induces an increase in intracellular ATP level, lysosomal alkalinization and ROS accumulation. - Abstract: The increased glycolysis and proton secretion in tumors is proposed to contribute to the proliferation and invasion of cancer cells during the process of tumorigenesis and metastasis. Here, treatment of human breast cancer cells with proton pump inhibitor (PPI) lansoprazole (LPZ) induces cell apoptosis in a dose-dependent manner. In the implantation of the MDA-MB-231 xenografts in nude mice, administration of LPZ significantly inhibits tumorigenesis and induces large-scale apopotosis of tumor cells. LPZ markedly inhibits intracellular proton extrusion, induces an increase in intracellular ATP level, lysosomal alkalinization and accumulation of reactive oxygen species (ROS) in breast cancer cells. The ROS scavenger N-acetyl-L-cysteine (NAC) and diphenyleneiodonium (DPI), a specific pharmacological inhibitor of NADPH oxidases (NOX), significantly abolish LPZ-induced ROS accumulation in breast cancer cells. Our results suggested that LPZ may be used as a new therapeutic drug for breast tumor.

  19. Sapodilla plum (Achras sapota) induces apoptosis in cancer cell lines and inhibits tumor progression in mice.

    PubMed

    Srivastava, Mrinal; Hegde, Mahesh; Chiruvella, Kishore K; Koroth, Jinsha; Bhattacharya, Souvari; Choudhary, Bibha; Raghavan, Sathees C

    2014-08-21

    Intake of fruits rich in antioxidants in daily diet is suggested to be cancer preventive. Sapota is a tropical fruit grown and consumed extensively in several countries including India and Mexico. Here we show that methanolic extracts of Sapota fruit (MESF) induces cytotoxicity in a dose-dependent manner in cancer cell lines. Cell cycle analysis suggested activation of apoptosis, without arresting cell cycle progression. Annexin V-propidium iodide double-staining demonstrated that Sapota fruit extracts potentiate apoptosis rather than necrosis in cancer cells. Loss of mitochondrial membrane potential, upregulation of proapoptotic proteins, activation of MCL-1, PARP-1, and Caspase 9 suggest that MESF treatment leads to activation of mitochondrial pathway of apoptosis. More importantly, we show that MESF treatment leads to significant inhibition of tumor growth and a 3-fold increase in the life span of tumor bearing animals compared to untreated tumor mice.

  20. Sapodilla Plum (Achras sapota) Induces Apoptosis in Cancer Cell Lines and Inhibits Tumor Progression in Mice

    PubMed Central

    Srivastava, Mrinal; Hegde, Mahesh; Chiruvella, Kishore K.; Koroth, Jinsha; Bhattacharya, Souvari; Choudhary, Bibha; Raghavan, Sathees C.

    2014-01-01

    Intake of fruits rich in antioxidants in daily diet is suggested to be cancer preventive. Sapota is a tropical fruit grown and consumed extensively in several countries including India and Mexico. Here we show that methanolic extracts of Sapota fruit (MESF) induces cytotoxicity in a dose-dependent manner in cancer cell lines. Cell cycle analysis suggested activation of apoptosis, without arresting cell cycle progression. Annexin V-propidium iodide double-staining demonstrated that Sapota fruit extracts potentiate apoptosis rather than necrosis in cancer cells. Loss of mitochondrial membrane potential, upregulation of proapoptotic proteins, activation of MCL-1, PARP-1, and Caspase 9 suggest that MESF treatment leads to activation of mitochondrial pathway of apoptosis. More importantly, we show that MESF treatment leads to significant inhibition of tumor growth and a 3-fold increase in the life span of tumor bearing animals compared to untreated tumor mice. PMID:25142835

  1. Catalase inhibits ionizing radiation-induced apoptosis in hematopoietic stem and progenitor cells.

    PubMed

    Xiao, Xia; Luo, Hongmei; Vanek, Kenneth N; LaRue, Amanda C; Schulte, Bradley A; Wang, Gavin Y

    2015-06-01

    Hematologic toxicity is a major cause of mortality in radiation emergency scenarios and a primary side effect concern in patients undergoing chemo-radiotherapy. Therefore, there is a critical need for the development of novel and more effective approaches to manage this side effect. Catalase is a potent antioxidant enzyme that coverts hydrogen peroxide into hydrogen and water. In this study, we evaluated the efficacy of catalase as a protectant against ionizing radiation (IR)-induced toxicity in hematopoietic stem and progenitor cells (HSPCs). The results revealed that catalase treatment markedly inhibits IR-induced apoptosis in murine hematopoietic stem cells and hematopoietic progenitor cells. Subsequent colony-forming cell and cobble-stone area-forming cell assays showed that catalase-treated HSPCs can not only survive irradiation-induced apoptosis but also have higher clonogenic capacity, compared with vehicle-treated cells. Moreover, transplantation of catalase-treated irradiated HSPCs results in high levels of multi-lineage and long-term engraftments, whereas vehicle-treated irradiated HSPCs exhibit very limited hematopoiesis reconstituting capacity. Mechanistically, catalase treatment attenuates IR-induced DNA double-strand breaks and inhibits reactive oxygen species. Unexpectedly, we found that the radioprotective effect of catalase is associated with activation of the signal transducer and activator of transcription 3 (STAT3) signaling pathway and pharmacological inhibition of STAT3 abolishes the protective activity of catalase, suggesting that catalase may protect HSPCs against IR-induced toxicity via promoting STAT3 activation. Collectively, these results demonstrate a previously unrecognized mechanism by which catalase inhibits IR-induced DNA damage and apoptosis in HSPCs.

  2. Quercetin induces HepG2 cell apoptosis by inhibiting fatty acid biosynthesis

    PubMed Central

    ZHAO, PENG; MAO, JUN-MIN; ZHANG, SHU-YUN; ZHOU, ZE-QUAN; TAN, YANG; ZHANG, YU

    2014-01-01

    Quercetin can inhibit the growth of cancer cells with the ability to act as a ‘chemopreventer’. Its cancer-preventive effect has been attributed to various mechanisms, including the induction of cell-cycle arrest and/or apoptosis, as well as its antioxidant functions. Quercetin can also reduce adipogenesis. Previous studies have shown that quercetin has potent inhibitory effects on animal fatty acid synthase (FASN). In the present study, activity of quercetin was evaluated in human liver cancer HepG2 cells. Intracellular FASN activity was calculated by measuring the absorption of NADPH via a spectrophotometer. MTT assay was used to test the cell viability, immunoblot analysis was performed to detect FASN expression levels and the apoptotic effect was detected by Hoechst 33258 staining. In the present study, it was found that quercetin could induce apoptosis in human liver cancer HepG2 cells with overexpression of FASN. This apoptosis was accompanied by the reduction of intracellular FASN activity and could be rescued by 25 or 50 μM exogenous palmitic acids, the final product of FASN-catalyzed synthesis. These results suggested that the apoptosis induced by quercetin was via the inhibition of FASN. These findings suggested that quercetin may be useful for preventing human liver cancer. PMID:25009654

  3. Quercetin induces HepG2 cell apoptosis by inhibiting fatty acid biosynthesis.

    PubMed

    Zhao, Peng; Mao, Jun-Min; Zhang, Shu-Yun; Zhou, Ze-Quan; Tan, Yang; Zhang, Yu

    2014-08-01

    Quercetin can inhibit the growth of cancer cells with the ability to act as a 'chemopreventer'. Its cancer-preventive effect has been attributed to various mechanisms, including the induction of cell-cycle arrest and/or apoptosis, as well as its antioxidant functions. Quercetin can also reduce adipogenesis. Previous studies have shown that quercetin has potent inhibitory effects on animal fatty acid synthase (FASN). In the present study, activity of quercetin was evaluated in human liver cancer HepG2 cells. Intracellular FASN activity was calculated by measuring the absorption of NADPH via a spectrophotometer. MTT assay was used to test the cell viability, immunoblot analysis was performed to detect FASN expression levels and the apoptotic effect was detected by Hoechst 33258 staining. In the present study, it was found that quercetin could induce apoptosis in human liver cancer HepG2 cells with overexpression of FASN. This apoptosis was accompanied by the reduction of intracellular FASN activity and could be rescued by 25 or 50 μM exogenous palmitic acids, the final product of FASN-catalyzed synthesis. These results suggested that the apoptosis induced by quercetin was via the inhibition of FASN. These findings suggested that quercetin may be useful for preventing human liver cancer.

  4. Growth Inhibition and Apoptosis Induced by Osthole, A Natural Coumarin, in Hepatocellular Carcinoma

    PubMed Central

    Zhang, Lurong; Jiang, Guorong; Yao, Fei; He, Yan; Liang, Guoqiang; Zhang, Yinsheng; Hu, Bo; Wu, Yan; Li, Yunsen; Liu, Haiyan

    2012-01-01

    Background Hepatocellular carcinoma (HCC) is one of the most commonly diagnosed tumors worldwide and is known to be resistant to conventional chemotherapy. New therapeutic strategies are urgently needed for treating HCC. Osthole, a natural coumarin derivative, has been shown to have anti-tumor activity. However, the effects of osthole on HCC have not yet been reported. Methods and Findings HCC cell lines were treated with osthole at various concentrations for 24, 48 and 72 hours. The proliferations of the HCC cells were measured by MTT assays. Cell cycle distribution and apoptosis were determined by flow cytometry. HCC tumor models were established in mice by subcutaneously injection of SMMC-7721 or Hepa1-6 cells and the effect of osthole on tumor growths in vivo and the drug toxicity were studied. NF-κB activity after osthole treatment was determined by electrophoretic mobility shift assays and the expression of caspase-3 was measured by western blotting. The expression levels of other apoptosis-related genes were also determined by real-time PCR (PCR array) assays. Osthole displayed a dose- and time-dependent inhibition of the HCC cell proliferations in vitro. It also induced apoptosis and caused cell accumulation in G2 phase. Osthole could significantly suppress HCC tumor growth in vivo with no toxicity at the dose we used. NF-κB activity was significantly suppressed by osthole at the dose- and time-dependent manner. The cleaved caspase-3 was also increased by osthole treatment. The expression levels of some apoptosis-related genes that belong to TNF ligand family, TNF receptor family, Bcl-2 family, caspase family, TRAF family, death domain family, CIDE domain and death effector domain family and CARD family were all increased with osthole treatment. Conclusion Osthole could significantly inhibit HCC growth in vitro and in vivo through cell cycle arrest and inducing apoptosis by suppressing NF-κB activity and promoting the expressions of apoptosis

  5. Raddeanin A induces human gastric cancer cells apoptosis and inhibits their invasion in vitro

    SciTech Connect

    Xue, Gang; Zou, Xi; Zhou, Jin-Yong; Sun, Wei; Wu, Jian; Xu, Jia-Li; Wang, Rui-Ping

    2013-09-20

    Highlights: •Raddeanin A is a triterpenoid saponin in herb medicine Anemone raddeana Regel. •Raddeanin A can inhibit 3 kinds of gastric cancer cells’ proliferation and invasion. •Caspase-cascades’ activation indicates apoptosis induced by Raddeanin A. •MMPs, RECK, Rhoc and E-cad are involved in Raddeanin A-induced invasion inhibition. -- Abstract: Raddeanin A is one of the triterpenoid saponins in herbal medicine Anemone raddeana Regel which was reported to suppress the growth of liver and lung cancer cells. However, little was known about its effect on gastric cancer (GC) cells. This study aimed to investigate its inhibitory effect on three kinds of different differentiation stage GC cells (BGC-823, SGC-7901 and MKN-28) in vitro and the possible mechanisms. Proliferation assay and flow cytometry demonstrated Raddeanin A’s dose-dependent inhibitory effect and determined its induction of cells apoptosis, respectively. Transwell assay, wounding heal assay and cell matrix adhesion assay showed that Raddeanin A significantly inhibited the abilities of the invasion, migration and adhesion of the BGC-823 cells. Moreover, quantitative real time PCR and Western blot analysis found that Raddeanin A increased Bax expression while reduced Bcl-2, Bcl-xL and Survivin expressions and significantly activated caspase-3, caspase-8, caspase-9 and poly-ADP ribose polymerase (PARP). Besides, Raddeanin A could also up-regulate the expression of reversion inducing cysteine rich protein with Kazal motifs (RECK), E-cadherin (E-cad) and down-regulate the expression of matrix metalloproteinases-2 (MMP-2), MMP-9, MMP-14 and Rhoc. In conclusion, Raddeanin A inhibits proliferation of human GC cells, induces their apoptosis and inhibits the abilities of invasion, migration and adhesion, exhibiting potential to become antitumor drug.

  6. Bushen Zhuangjin decoction inhibits TM-induced chondrocyte apoptosis mediated by endoplasmic reticulum stress

    PubMed Central

    LIN, PINGDONG; WENG, XIAPING; LIU, FAYUAN; MA, YUHUAN; CHEN, HOUHUANG; SHAO, XIANG; ZHENG, WENWEI; LIU, XIANXIANG; YE, HONGZHI; LI, XIHAI

    2015-01-01

    Chondrocyte apoptosis triggered by endoplasmic reticulum (ER) stress plays a vital role in the pathogenesis of osteoarthritis (OA). Bushen Zhuangjin decoction (BZD) has been widely used in the treatment of OA. However, the cellular and molecular mechanisms responsible for the inhibitory effects of BZD on chondrocyte apoptosis remain to be elucidated. In the present study, we investigated the effects of BZD on ER stress-induced chondrocyte apoptosis using a chondrocyte in vitro model of OA. Chondrocytes obtained from the articular cartilage of the knee joints of Sprague Dawley (SD) rats were detected by immunohistochemical staining for type II collagen. The ER stress-mediated apoptosis of tunicamycin (TM)-stimulated chondrocytes was detected using 4-phenylbutyric acid (4-PBA). We found that 4-PBA inhibited TM-induced chondrocyte apoptosis, which confirmed the successful induction of chondrocyte apoptosis. BZD enhanced the viability of the TM-stimulated chondrocytes in a dose- and time-dependent manner, as shown by MTT assay. The apoptotic rate and the loss of mitochondrial membrane potential (ΔΨm) of the TM-stimulated chondrocytes treated with BZD was markedly decreased compared with those of chondrocytes not treated with BZD, as shown by 4′,6-diamidino-2-phenylindole (DAPI) staining, Annexin V-FITC binding assay and JC-1 assay. To further elucidate the mechanisms responsible for the inhibitory effects of BZD on TM-induced chondrocyte apoptosis mediated by ER stress, the mRNA and protein expression levels of binding immunoglobulin protein (Bip), X-box binding protein 1 (Xbp1), activating transcription factor 4 (Atf4), C/EBP-homologous protein (Chop), caspase-9, caspase-3, B-cell lymphoma 2 (Bcl-2) and Bcl-2-associated X protein (Bax) were measured by reverse transcription-polymerase chain reaction (RT-PCR) and western blot analysis. In the TM-stimulated chondrocytes treated with BZD, the mRNA and protein expression levels of Bip, Atf4, Chop, caspase-9, caspase-3

  7. Bushen Zhuangjin decoction inhibits TM-induced chondrocyte apoptosis mediated by endoplasmic reticulum stress.

    PubMed

    Lin, Pingdong; Weng, Xiaping; Liu, Fayuan; Ma, Yuhuan; Chen, Houhuang; Shao, Xiang; Zheng, Wenwei; Liu, Xianxiang; Ye, Hongzhi; Li, Xihai

    2015-12-01

    Chondrocyte apoptosis triggered by endoplasmic reticulum (ER) stress plays a vital role in the pathogenesis of osteoarthritis (OA). Bushen Zhuangjin decoction (BZD) has been widely used in the treatment of OA. However, the cellular and molecular mechanisms responsible for the inhibitory effects of BZD on chondrocyte apoptosis remain to be elucidated. In the present study, we investigated the effects of BZD on ER stress-induced chondrocyte apoptosis using a chondrocyte in vitro model of OA. Chondrocytes obtained from the articular cartilage of the knee joints of Sprague Dawley (SD) rats were detected by immunohistochemical staining for type Ⅱ collagen. The ER stress-mediated apoptosis of tunicamycin (TM)‑stimulated chondrocytes was detected using 4-phenylbutyric acid (4‑PBA). We found that 4‑PBA inhibited TM-induced chondrocyte apoptosis, which confirmed the successful induction of chondrocyte apoptosis. BZD enhanced the viability of the TM-stimulated chondrocytes in a dose- and time-dependent manner, as shown by MTT assay. The apoptotic rate and the loss of mitochondrial membrane potential (ΔΨm) of the TM-stimulated chondrocytes treated with BZD was markedly decreased compared with those of chondrocytes not treated with BZD, as shown by 4',6-diamidino-2-phenylindole (DAPI) staining, Annexin V-FITC binding assay and JC-1 assay. To further elucidate the mechanisms responsible for the inhibitory effects of BZD on TM‑induced chondrocyte apoptosis mediated by ER stress, the mRNA and protein expression levels of binding immunoglobulin protein (Bip), X‑box binding protein 1 (Xbp1), activating transcription factor 4 (Atf4), C/EBP‑homologous protein (Chop), caspase‑9, caspase-3, B-cell lymphoma 2 (Bcl-2) and Bcl-2-associated X protein (Bax) were measured by reverse transcription-polymerase chain reaction (RT-PCR) and western blot analysis. In the TM-stimulated chondrocytes treated with BZD, the mRNA and protein expression levels of Bip, Atf4, Chop, caspase

  8. Inhibition of tissue transglutaminase promotes Aβ-induced apoptosis in SH-SY5Y cells

    PubMed Central

    Zhang, Ji; Ding, Yi-rong; Wang, Rui

    2016-01-01

    Aim: Tissue transglutaminase (tTG) catalyzes proteins, including β-amyloid (Aβ), to cross-link as a γ-glutamyl-ε-lysine structure isopeptide, which is highly resistant to proteolysis. Thus, tTG plays an important role in protein accumulation in Alzheimer's disease (AD). In the present study, we examined the effect of an irreversible tTG inhibitor, NTU283, on Aβ mimic-induced AD pathogenesis in SH-SY5Y cells. Methods: Western blot and in-cell Western analyses were used to detect tTG and isopeptide (representing the enzyme activity of tTG) protein levels. Moreover, Hoechst and PI co-staining was performed, and caspase-3 and caspase-7 activities and the Bax/Bcl-2 ratio were determined to evaluate the effects of NTU283 on apoptosis. Results: The results confirmed that tTG activity was inhibited by NTU283 20–500 μmol/L in a concentration-dependent manner in SH-SY5Y cells. Contrary to our expectations, however, the isopeptide bonds were increased when cells were co-treated with Aβ and NTU283. In addition, NTU283 alone did not induce apoptosis in SH-SY5Y cells. However, when co-applied with Aβ, NTU283 promoted rather than inhibited Aβ-induced apoptosis. Consistent with the apoptotic rate, pretreating cells with different concentrations of NTU283 and Aβ significantly increased the activities of caspase-3 and caspase-7 as well as the ratio of Bax/Bcl-2. Conclusion: Irreversible inhibition of tTG activity did not block but rather promoted Aβ-induced apoptosis, which indicated that tTG has complex functions in AD pathogenesis. PMID:27665848

  9. Zinc inhibits oxidative stress-induced iron signaling and apoptosis in Caco-2 cells.

    PubMed

    Kilari, Sreenivasulu; Pullakhandam, Raghu; Nair, K Madhavan

    2010-04-01

    Studies in humans and animals have suggested negative interactions of iron and zinc during their intestinal absorption. Further, zinc seems to prevent iron-induced oxidative damage in rats, which was hypothesized to be through the modulation of the intracellular iron signaling pathway. The aim of this study was, therefore, to understand the effects of zinc on oxidant-induced iron signaling and cell death in human enterocyte-like Caco-2 cells. We demonstrate that zinc decreases glucose/glucose oxidase (H(2)O(2)-generating system)-induced iron uptake and inhibits iron-regulatory protein 1 activation and divalent metal ion transporter 1 expression. There was also a concomitant decrease in oxidant-induced intracellular labile iron and restoration of ferritin and metallothionein expression. Further, zinc enhanced the Bcl-2/Bax ratio and reduced caspase-3 activity, leading to inhibition of apoptosis. Interestingly, bathophenanthroline disulfonic acid, an extracellular iron chelator, emulated the effects of zinc except for the reduced ferritin levels. These results suggest that zinc inhibits apoptosis by reducing oxidant-induced iron signaling in Caco-2 cells.

  10. Inhibition of NF-κB activity and cFLIP expression contribute to viral-induced apoptosis

    PubMed Central

    Clarke, P.; DeBiasi, R. L.; Meintzer, S. M.; Robinson, B. A.; Tyler, K. L.

    2008-01-01

    Virus-induced activation of nuclear factor-kappa B (NF-κB) is required for Type 3 (T3) reovirus-induced apoptosis. We now show that NF-κB is also activated by the prototypic Type 1 reovirus strain Lang (T1L), which induces significantly less apoptosis than T3 viruses, indicating that NF-κB activation alone is not sufficient for apoptosis in reovirus-infected cells. A second phase of virus-induced NF-κB regulation, where NF-κB activation is inhibited at later times following infection with T3 Abney (T3A), is absent in T1L-infected cells. This suggests that inhibition of NF-κB activation at later times post infection also contributes to reovirus-induced apoptosis. Reovirus-induced inhibition of stimulus-induced activation of NF-κB is significantly associated with apoptosis following infection of HEK293 cells with reassortant reoviruses and is determined by the T3 S1 gene segment, which is also the primary determinant of reovirus-induced apoptosis. Inhibition of stimulus-induced activation of NF-κB also occurs following infection of primary cardiac myocytes with apoptotic (8B) but not non-apoptotic (T1L) reoviruses. Expression levels of the NF-κB-regulated cellular FLICE inhibitory protein (cFLIP) reflect NF-κB activation in reovirus-infected cells. Further, inhibition of NF-κB activity and cFLIP expression promote T1L-induced apoptosis. These results demonstrate that inhibition of stimulus-induced activation of NF-κB and the resulting decrease in cFLIP expression promote reovirus-induced apoptosis. PMID:15909114

  11. Lansoprazole induces apoptosis of breast cancer cells through inhibition of intracellular proton extrusion.

    PubMed

    Zhang, Shangrong; Wang, Yifan; Li, Shu Jie

    2014-06-13

    The increased glycolysis and proton secretion in tumors is proposed to contribute to the proliferation and invasion of cancer cells during the process of tumorigenesis and metastasis. Here, treatment of human breast cancer cells with proton pump inhibitor (PPI) lansoprazole (LPZ) induces cell apoptosis in a dose-dependent manner. In the implantation of the MDA-MB-231 xenografts in nude mice, administration of LPZ significantly inhibits tumorigenesis and induces large-scale apopotosis of tumor cells. LPZ markedly inhibits intracellular proton extrusion, induces an increase in intracellular ATP level, lysosomal alkalinization and accumulation of reactive oxygen species (ROS) in breast cancer cells. The ROS scavenger N-acetyl-l-cysteine (NAC) and diphenyleneiodonium (DPI), a specific pharmacological inhibitor of NADPH oxidases (NOX), significantly abolish LPZ-induced ROS accumulation in breast cancer cells. Our results suggested that LPZ may be used as a new therapeutic drug for breast tumor.

  12. Paeoniflorin inhibits doxorubicin-induced cardiomyocyte apoptosis by downregulating microRNA-1 expression

    PubMed Central

    LI, JIAN-ZHE; TANG, XIU-NENG; LI, TING-TING; LIU, LI-JUAN; YU, SHU-YI; ZHOU, GUANG-YU; SHAO, QING-RUI; SUN, HUI-PING; WU, CHENG; YANG, YANG

    2016-01-01

    Doxorubicin (DOX) is an effective anthracycline anti-tumor antibiotic. Because of its cardiotoxicity, the clinical application of DOX is limited. Paeoniflorin (PEF), a monoterpene glucoside extracted from the dry root of Paeonia, is reported to exert multiple beneficial effects on the cardiovascular system. The present study was designed to explore the protective effect of PEF against DOX-induced cardiomyocyte apoptosis and the underlying mechanism. In cultured H9c2 cells, PEF (100 µmol/l) was added for 2 h prior to exposure to DOX (5 µmol/l) for 24 h. Cell viability, creatine kinase activity, cardiomyocyte apoptosis, intracellular reactive oxygen species (ROS) levels, and the expression of microRNA-1 (miR-1) and B-cell lymphoma 2 (Bcl-2) were measured following treatment with PEF and/or DOX. The results showed that treatment with DOX notably induced cardiomyocyte apoptosis, concomitantly with enhanced ROS generation, upregulated miR-1 expression and downregulated Bcl-2 expression. These effects of DOX were significantly inhibited by pretreatment of the cells with PEF. These results suggest that the inhibitory effect of PEF on DOX-induced cardiomyocyte apoptosis may be associated with downregulation of miR-1 expression via a reduction in ROS generation. PMID:27284328

  13. Inhibition of RNA transportation induces glioma cell apoptosis via downregulation of RanGAP1 expression.

    PubMed

    Lin, Tsung-Yao; Lee, Chin-Cheng; Chen, Ku-Chung; Lin, Chien-Ju; Shih, Chwen-Ming

    2015-05-05

    The prognosis of glioblastoma remains poor, even treatment with surgery, radiation, or chemotherapy. Therefore, it is still important to develop a new strategy for treatment of glioblastoma. Previous reports demonstrated that rRNA is produced at abnormally high levels in tumor cells. Nuclear export of all non-coding RNAs are known to depend on RanGTPase system. Hydrolyzation of RanGTP-RNA complex by RanGTPase activating protein 1 (RanGAP1) releases RNA from nucleus to cytoplasm. Therefore, inhibition of RNA transportation would be a useful strategy to affect cancer cell fate. In this study, 5-30 μM of oridonin, a natural diterpenoid compound isolated from the traditional Chinese medicine, Rabdosia rubescens, induced U87MG glioma cell apoptosis and RNA accumulation in nucleus at 12h-time point. Before U87MG cell apoptosis, the RanGAP1 protein amount decreased and RanGTP accumulated in nucleus as respectively determined by immunoprecipitation and immunofluorescence, suggesting that decrease of RanGAP1 may result in nuclear entrapment of RanGTP and RNA, and then induce U87MG cell death. In contrast, over-expression of the RanGAP1 protein reversed oridonin-induced U87MG cell apoptosis. Hence, we demonstrated that downregulation of the RanGAP1 protein level by oridonin may result in RNA accumulation in nucleus via nuclear entrapment of RanGTP which eventually led to the apoptosis of glioma cells.

  14. Aminoguanidine inhibits reactive oxygen species formation, lipid peroxidation, and oxidant-induced apoptosis.

    PubMed

    Giardino, I; Fard, A K; Hatchell, D L; Brownlee, M

    1998-07-01

    Aminoguanidine (AG) treatment, like nerve growth factor (NGF) treatment, prevents diabetes-induced apoptosis of retinal Müller cells in the rat eye, but the mechanism involved is unknown. In this study, the effects of preincubation with AG on oxidant-induced apoptosis, oxidant-induced intracellular reactive oxygen species (ROS) production, and lipid peroxidation were determined in rat retinal Müller cells and compared with the effects of NGF, a protein that protects neuronal cells from oxidative stress. The effect of AG on rabbit vitreous lipid peroxide levels was also determined. After exposure to increasing concentrations of H2O2, there was a corresponding increase in the percentage of apoptotic Müller cells. Preincubation with AG for 48 h completely inhibited oxidant-induced apoptosis in response to 10 micromol/l H2O2 (+AG 0 vs. 10 micromol/l, NS), and reduced the percentage of apoptotic cells in response to 50 micromol/l H2O2 by 50% (+AG vs. -AG, P < 0.01). Longer preincubation did not increase the antiapoptotic effect of AG. The effect of AG was dose-dependent. Similar results were obtained after preincubation with NGF. Both AG and NGF preincubation prevented the twofold increase in oxidant-induced lipid peroxides. The fivefold increase in oxidant-induced ROS production was decreased 100% by NGF, but only 61% by AG preincubation. The twofold increase in vitreous lipid peroxide level in diabetic rabbits was completely prevented by AG treatment. AG reduced H2O2-induced benzoate hydroxylation in a dose-dependent manner. Intracellular glutathione content was unchanged. These data demonstrate that AG can act as an antioxidant in vivo, quenching hydroxyl radicals and lipid peroxidation in cells and tissues and preventing oxidant-induced apoptosis.

  15. Thromboxane synthase suppression induces lung cancer cell apoptosis via inhibiting NF-{kappa}B

    SciTech Connect

    Leung, Kin Chung; Li, Ming-Yue; Leung, Billy C.S.; Hsin, Michael K.Y.; Mok, Tony S.K.; Underwood, Malcolm J.; Chen, George G.

    2010-12-10

    Accumulating evidence shows that the inhibition of thromboxane synthase (TXS) induced apoptosis in cancer cells. TXS inhibitor 1-Benzylimidzole (1-BI) can trigger apoptosis in lung cancer cells but the mechanism is not fully defined. In this study, lung cancer cells were treated with 1-BI. In this study, the level of reactive oxygen species (ROS) was measured and NF-{kappa}B activity was determined in human lung cancer cells. The roles of ROS and NF-{kappa}B in 1-BI-mediated cell death were analyzed. The results showed that 1-BI induced ROS generation but decreased the activity of NF-{kappa}B by reducing phosphorylated I{kappa}B{alpha} (p-I{kappa}B{alpha}) and inhibiting the translocation of p65 into the nucleus. In contrast to 1-BI, antioxidant N-acetyl cysteine (NAC) stimulated cell proliferation and significantly protected the cells from 1-BI-mediated cell death by neutralizing ROS. Collectively, apoptosis induced by 1-BI is associated with the over-production of ROS and the reduction of NF-{kappa}B. Antioxidants can significantly block the inhibitory effect of 1-BI.

  16. Inhibition of focal adhesion kinase induces apoptosis in human osteosarcoma SAOS-2 cells.

    PubMed

    Wang, Jialiang; Zu, Jianing; Xu, Gongping; Zhao, Wei; Jinglong, Yan

    2014-02-01

    Focal adhesion kinase (FAK), a non-receptor tyrosine kinase protein, acts as an early modulator of integrin signaling cascade, regulating basic cellular functions. In transformed cells, unopposed FAK signaling has been considered to promote tumor growth, progression, and metastasis. The aim of this study was to assess the role of focal adhesion kinase in human osteosarcoma SAOS-2 cells. SAOS-2 cells were transfected with PGPU6/GFP/shNC, and PGPU6/GFP/FAK-334 (shRNA-334), respectively. Expression of FAK was detected by real-time PCR and western blots. MTT assay was used to examine changes in cell proliferation. Cell apoptosis was analyzed by flow cytometry. The expression of caspase-3,-7,-9 was measured by Western blots. The expression of FAK in SAOS-2 cells significantly decreased in shRNA-334 group contrast to the control group (P < 0.01). Cells proliferation was inhibited by shRNA-334 and shRNA-334 + cisplatin, and the effects were clearly enhanced when cells treated with the anticancer agents. The level of cell apoptosis in shRNA-334 and shRNA-334 + cisplatin group was higher than in the control group (P < 0.01). The current data support evidence that down-regulation of FAK could induce SAOS-2 apoptosis through the caspase-dependent cell death pathway. Inhibition of the kinases may be important for therapies designed to enhance the apoptosis in osteosarcoma.

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

    PubMed

    Ge, Yanli; Zhang, Junjie; Cao, Jianchun; Wu, Qiong; Sun, Longe; Guo, Likun; Wang, Zhirong

    2012-05-01

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

  18. WWOX induces apoptosis and inhibits proliferation of human hepatoma cell line SMMC-7721

    PubMed Central

    Hu, Ben-Shun; Tan, Jing-Wang; Zhu, Guo-Hua; Wang, Dan-Feng; Zhou, Xian; Sun, Zhi-Qiang

    2012-01-01

    AIM: To investigate the effects of the WWOX gene on the human hepatic carcinoma cell line SMMC-7721. METHODS: Full-length WWOX cDNA was amplified from normal human liver tissues. Full-length cDNA was subcloned into pEGFP-N1, a eukaryotic expression vector. After introduction of the WWOX gene into cancer cells using liposomes, the WWOX protein level in the cells was detected through Western blotting. Cell growth rates were assessed by methyl thiazolyl tetrazolium (MTT) and colony formation assays. Cell cycle progression and cell apoptosis were measured by flow cytometry. The phosphorylated protein kinase B (AKT) and activated fragments of caspase-9 and caspase-3 were examined by Western blotting analysis. RESULTS: WWOX significantly inhibited cell proliferation, as evaluated by the MTT and colony formation assays. Cells transfected with WWOX showed significantly higher apoptosis ratios when compared with cells transfected with a mock plasmid, and overexpression of WWOX delayed cell cycle progression from G1 to S phase, as measured by flow cytometry. An increase in apoptosis was also indicated by a remarkable activation of caspase-9 and caspase-3 and a dephosphorylation of AKT (Thr308 and Ser473) measured with Western blotting analysis. CONCLUSION: Overexpression of WWOX induces apoptosis and inhibits proliferation of the human hepatic carcinoma cell line SMMC-7721. PMID:22736928

  19. Gambogic acid inhibits growth, induces apoptosis, and overcomes drug resistance in human colorectal cancer cells

    PubMed Central

    WEN, CHUANGYU; HUANG, LANLAN; CHEN, JUNXIONG; LIN, MENGMENG; LI, WEN; LU, BIYAN; RUTNAM, ZINA JEYAPALAN; IWAMOTO, AIKICHI; WANG, ZHONGYANG; YANG, XIANGLING; LIU, HUANLIANG

    2015-01-01

    The emergence of chemoresistance is a major limitation of colorectal cancer (CRC) therapies and novel biologically based therapies are urgently needed. Natural products represent a novel potential anticancer therapy. Gambogic acid (GA), a small molecule derived from Garcinia hanburyi Hook. f., has been demonstrated to be highly cytotoxic to several types of cancer cells and have low toxicity to the hematopoietic system. However, the potential role of GA in colorectal cancer and its ability to overcome the chemotherapeutic resistance in CRC cells have not been well studied. In the present study, we showed that GA directly inhibited proliferation and induced apoptosis in both 5-fluorouracil (5-FU) sensitive and 5-FU resistant colorectal cancer cells; induced apoptosis via activating JNK signaling pathway. The data, therefore, suggested an alternative strategy to overcome 5-FU resistance in CRC and that GA could be a promising medicinal compound for colorectal cancer therapy. PMID:26397804

  20. Inhibition of SGK1 enhances mAR-induced apoptosis in MCF-7 breast cancer cells.

    PubMed

    Liu, Guilai; Honisch, Sabina; Liu, Guoxing; Schmidt, Sebastian; Pantelakos, Stavros; Alkahtani, Saad; Toulany, Mahmoud; Lang, Florian; Stournaras, Christos

    2015-01-01

    Functional membrane androgen receptors (mAR) have previously been described in MCF-7 breast cancer cells. Their stimulation by specific testosterone albumin conjugates (TAC) activate rapidly non-genomic FAK/PI3K/Rac1/Cdc42 signaling, trigger actin reorganization and inhibit cell motility. PI3K stimulates serum and glucocorticoid inducible kinase SGK1, which in turn regulates the function of mAR. In the present study we addressed the role of SGK1 in mAR-induced apoptosis. TAC-stimulated mAR activation elicited apoptosis of MCF-7 cells, an effect significantly potentiated by concomitant incubation of the cells with TAC and the specific SGK1 inhibitors EMD638683 and GSK650394. In line with this, TAC and EMD638683 activated caspase-3. These effects were insensitive to the classical androgen receptor (iAR) antagonist flutamide, pointing to iAR-independent, mAR-induced responses. mAR activation and SGK1 inhibition further considerably augmented the radiation-induced apoptosis of MCF-7 cells. Moreover, TAC- and EMD638683 triggered early actin polymerization in MCF-7 cells. Blocking actin restructuring with cytochalasin B abrogated the TAC- and EMD638683-induced pro-apoptotic responses. Further analysis of the molecular signaling revealed late de-phosphorylation of FAK and Akt. Our results demonstrate that mAR activation triggers pro-apoptotic responses in breast tumor cells, an effect significantly enhanced by SGK1 inhibition, involving actin reorganization and paralleled by down-regulation of FAK/Akt signaling.

  1. Inhibition of histone deacetylases by chlamydocin induces apoptosis and proteasome-mediated degradation of survivin.

    PubMed

    De Schepper, Stefanie; Bruwiere, Hélène; Verhulst, Tinne; Steller, Ulf; Andries, Luc; Wouters, Walter; Janicot, Michel; Arts, Janine; Van Heusden, Jim

    2003-02-01

    The naturally occurring cyclic tetrapeptide chlamydocin is a very potent inhibitor of cell proliferation. Here we show that chlamydocin is a highly potent histone deacetylase (HDAC) inhibitor, inhibiting HDAC activity in vitro with an IC(50) of 1.3 nM. Like other HDAC inhibitors, chlamydocin induces the accumulation of hyperacetylated histones H3 and H4 in A2780 ovarian cancer cells, increases the expression of p21(cip1/waf1), and causes an accumulation of cells in G(2)/M phase of the cell cycle. In addition, chlamydocin induces apoptosis by activating caspase-3, which in turn leads to the cleavage of p21(cip1/waf1) into a 15-kDa breakdown product and drives cells from growth arrest into apoptosis. Concomitant with the activation of caspase-3 and cleavage of p21(cip1/waf1), chlamydocin decreases the protein level of survivin, a member of the inhibitor of apoptosis protein family that is selectively expressed in tumors. Although our data indicate a potential link between degradation of survivin and activation of the apoptotic pathway induced by HDAC inhibitors, stable overexpression of survivin does not suppress the activation of caspase-3 or cleavage of p21(cip1/waf1) induced by chlamydocin treatment. The decrease of survivin protein level is mediated by degradation via proteasomes since it can be inhibited by specific proteasome inhibitors. Taken together, our results show that induction of apoptosis by chlamydocin involves caspase-dependent cleavage of p21(cip1/waf1), which is strikingly associated with proteasome-mediated degradation of survivin.

  2. The recombinant beta subunit of C-phycocyanin inhibits cell proliferation and induces apoptosis.

    PubMed

    Wang, Haizhen; Liu, Yongding; Gao, Xueliang; Carter, Christie L; Liu, Zhi-Ren

    2007-03-08

    C-Phycocyanin (C-PC) from blue-green algae has been reported to have various pharmacological characteristics, including anti-inflammatory and anti-tumor activities. In this study, we expressed the beta-subunit of C-PC (ref to as C-PC/beta) in Escherichia coli. We found that the recombinant C-PC/beta has anti-cancer properties. Under the treatment of 5 microM of the recombinant C-PC/beta, four different cancer cell lines accrued high proliferation inhibition and apoptotic induction. Substantially, a lower response occurred in non-cancer cells. We investigated the mechanism by which C-PC/beta inhibits cancer cell proliferation and induces apoptosis. We found that the C-PC/beta interacts with membrane-associated beta-tubulin and glyceraldehyde-3-phosphate dehydrogenase (GAPDH). Under the treatment of the C-PC/beta, depolymerization of microtubules and actin-filaments were observed. The cells underwent apoptosis with an increase in caspase-3, and caspase-8 activities. The cell cycle was arrested at the G0/G1 phase under the treatment of C-PC/beta. In addition, the nuclear level of GAPDH decreased significantly. Decrease in the nuclear level of GAPDH prevents the cell cycle from entering into the S phase. Inhibition of cancer cell proliferation and induction of apoptosis may potentate the C-PC/beta as a promising cancer prevention or therapy agent.

  3. Schisandrin B inhibits cell proliferation and induces apoptosis in human cholangiocarcinoma cells

    PubMed Central

    Yang, Xiaohui; Wang, Shuai; Mu, Yunchuan; Zheng, Yixiong

    2016-01-01

    Cholangiocarcinoma (CCA) is the second most common hepatic cancer with high resistance to current chemotherapies and extremely poor prognosis. The present study aimed to examine the effects of schisandrin B (Sch B) on CCA cells both in vitro and in vivo and to examine its underlying mechanism. We found that Sch B inhibited the viability and proliferation of CCA cells in a dose- and time-dependent manner as assessed by MTT and colony formation assays. The flow cytometric assay revealed G0/G1 phase arrest in the Sch B-treated HCCC-9810 and RBE cells. In addition, Sch B induced intrahepatic cholangiocarcinoma apoptosis as shown by the results of Annexin V/PI double staining. Rhodamine 123 staining revealed that Sch B decreased the mitochondrial membrane potential (ΔΨm) in a dose-dependent manner. Mechanistically, western blot analysis indicated that Sch B induced apoptosis by upregulating Bax, cleaved caspase-3, cleaved caspase-9 and cleaved PARP, and by downregulating cyclin D1, Bcl-2 and CDK-4. Moreover, Sch B significantly inhibited HCCC-9810 xenograft growth in athymic nude mice. In summary, these findings suggest that Sch B exhibited potent antitumor activities via the induction of CCA apoptosis and that Sch B may be a promising drug for the treatment of CCA. PMID:27499090

  4. Isoliquiritigenin induces apoptosis and autophagy and inhibits endometrial cancer growth in mice

    PubMed Central

    Shieh, Tzong-Ming; Huang, Tsui-Chin; Lin, Li-Chun; Wang, Kai-Lee; Hsia, Shih-Min

    2016-01-01

    Endometrial cancer is the most common cancer in women, typically with onset after menopause. Isoliquiritigenin (ISL), a licorice flavonoid, was previously shown to have anti-oxidant, anti-inflammatory, and tumor suppression effects. In this study, we investigated the anti-tumor effect of ISL on human endometrial cancer both in vitro and in vivo. We used telomerase-immortalized human endometrial stromal cells (T-HESCs) and human endometrial cancer cell lines (Ishikawa, HEC-1A, and RL95-2 cells) as targets. The effects of ISL on cell proliferation, cell cycle regulation, and apoptosis or autophagy-related protein expression were examined. In addition, we conducted in vivo experiments to confirm the inhibitory effects of ISL on cancer cells. ISL significantly inhibited the viability of cancer cells in a dose- and time-dependent manner but with little toxicity on normal cells. In addition, flow cytometry analysis indicated that ISL induced sub-G1 or G2/M phase arrest. ISL treatment activated the extracellular signal regulated kinase signaling pathway to enhance the protein expression of caspase-7/LC3BII associated with apoptosis/autophagy. Furthermore, ISL suppressed xenograft tumor growth in vivo. Taken together, these findings suggest that ISL may induce apoptosis, autophagy, and cell growth inhibition, indicating its potential as a therapeutic agent for human endometrial cancer. PMID:27708238

  5. Schisandrin B inhibits cell proliferation and induces apoptosis in human cholangiocarcinoma cells.

    PubMed

    Yang, Xiaohui; Wang, Shuai; Mu, Yunchuan; Zheng, Yixiong

    2016-10-01

    Cholangiocarcinoma (CCA) is the second most common hepatic cancer with high resistance to current chemotherapies and extremely poor prognosis. The present study aimed to examine the effects of schisandrin B (Sch B) on CCA cells both in vitro and in vivo and to examine its underlying mechanism. We found that Sch B inhibited the viability and proliferation of CCA cells in a dose- and time-dependent manner as assessed by MTT and colony formation assays. The flow cytometric assay revealed G0/G1 phase arrest in the Sch B-treated HCCC-9810 and RBE cells. In addition, Sch B induced intrahepatic cholangiocarcinoma apoptosis as shown by the results of Annexin V/PI double staining. Rhodamine 123 staining revealed that Sch B decreased the mitochondrial membrane potential (ΔΨm) in a dose-dependent manner. Mechanistically, western blot analysis indicated that Sch B induced apoptosis by upregulating Bax, cleaved caspase-3, cleaved caspase-9 and cleaved PARP, and by downregulating cyclin D1, Bcl-2 and CDK-4. Moreover, Sch B significantly inhibited HCCC-9810 xenograft growth in athymic nude mice. In summary, these findings suggest that Sch B exhibited potent antitumor activities via the induction of CCA apoptosis and that Sch B may be a promising drug for the treatment of CCA.

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

    PubMed

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

    2015-09-01

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

  7. XIAP inhibits mature Smac-induced apoptosis by degrading it through ubiquitination in NSCLC

    PubMed Central

    Qin, Sida; Yang, Chengcheng; Zhang, Boxiang; Li, Xiang; Sun, Xin; Li, Gang; Zhang, Jing; Xiao, Guodong; Gao, Xiao; Huang, Guanghong; Wang, Peili; Ren, Hong

    2016-01-01

    X-linked inhibitor of apoptosis protein (XIAP) and second mitochondrial-derived activator of caspase (Smac) are two important prognostic biomarkers for cancer. They are negatively correlated in many types of cancer. However, their relationship is still unknown in lung cancer. In the present study, we found that there was a negative correlation between Smac and XIAP at the level of protein but not mRNA in NSCLC patients. However, XIAP overexpression had no effect on degrading endogenous Smac in lung cancer cell lines. Therefore, we constructed plasmids with full length of Smac (fSmac) and mature Smac (mSmac) which located in cytoplasm instead of original mitochondrial location, and was confirmed by immunofluorescence. Subsequently, we found that mSmac rather than fSmac was degraded by XIAP and inhibited cell viability. CHX chase assay and ubiquitin assay were performed to illustrate XIAP degraded mSmac through ubiquitin pathway. Overexpression of XIAP partially reverted apoptotic induction and cell viability inhibition by mSmac, which was due to inhibiting caspase-3 activation. In nude mouse xenograft experiments, mSmac inhibited Ki-67 expression and slowed down lung cancer growth, while XIAP partially reversed the effect of mSmac by degrading it. In conclusion, XIAP inhibits mature Smac-induced apoptosis by degrading it through ubiquitination in NSCLC. PMID:27498621

  8. Wip1 inhibitor GSK2830371 inhibits neuroblastoma growth by inducing Chk2/p53-mediated apoptosis

    PubMed Central

    Chen, Zhenghu; Wang, Long; Yao, Dayong; Yang, Tianshu; Cao, Wen-Ming; Dou, Jun; Pang, Jonathan C.; Guan, Shan; Zhang, Huiyuan; Yu, Yang; Zhao, Yanling; Wang, Yongfeng; Xu, Xin; Shi, Yan; Patel, Roma; Zhang, Hong; Vasudevan, Sanjeev A.; Liu, Shangfeng; Yang, Jianhua; Nuchtern, Jed G.

    2016-01-01

    Neuroblastoma (NB) is the most common extracranial tumor in children. Unlike in most adult tumors, tumor suppressor protein 53 (p53) mutations occur with a relatively low frequency in NB and the downstream function of p53 is intact in NB cell lines. Wip1 is a negative regulator of p53 and hindrance of Wip1 activity by novel inhibitor GSK2830371 is a potential strategy to activate p53’s tumor suppressing function in NB. Yet, the in vivo efficacy and the possible mechanisms of GSK2830371 in NB have not yet been elucidated. Here we report that novel Wip1 inhibitor GSK2830371 induced Chk2/p53-mediated apoptosis in NB cells in a p53-dependent manner. In addition, GSK2830371 suppressed the colony-formation potential of p53 wild-type NB cell lines. Furthermore, GSK2830371 enhanced doxorubicin- (Dox) and etoposide- (VP-16) induced cytotoxicity in a subset of NB cell lines, including the chemoresistant LA-N-6 cell line. More importantly, GSK2830371 significantly inhibited tumor growth in an orthotopic xenograft NB mouse model by inducing Chk2/p53-mediated apoptosis in vivo. Taken together, this study suggests that GSK2830371 induces Chk2/p53-mediated apoptosis both in vitro and in vivo in a p53 dependent manner. PMID:27991505

  9. Cordycepin Induces Apoptosis and Inhibits Proliferation of Human Lung Cancer Cell Line H1975 via Inhibiting the Phosphorylation of EGFR.

    PubMed

    Wang, Zheng; Wu, Xue; Liang, Yan-Ni; Wang, Li; Song, Zhong-Xing; Liu, Jian-Li; Tang, Zhi-Shu

    2016-09-27

    Cordycepin is an active component of the traditional Chinese medicine Cordyceps sinensis and Cordyceps militaris with notable anticancer activity. Though the prominent inhibitory activity was reported in different kinds of cancer cell lines, the concrete mechanisms remain elusive. It was reported that cordycepin could be converted into tri-phosphates in vivo to confuse a number of enzymes and interfere the normal cell function. For the inhibitory mechanism of EGFR inhibitors and the structure similarity of ATP and tri-phosphated cordycepin, human lung cancer cell line H1975 was employed to investigate the inhibitory effect of cordycepin. The results showed that cordycepin could inhibit cell proliferation and induce apoptosis in a dose-dependent manner. Cell cycle analysis revealed that H1975 cells could be arrested at the G₀/G₁ phase after cordycepin treatment. The expression levels of apoptosis-related protein Caspase-3 and Bcl-2 and phosphorylated expression levels of EGFR, AKT and ERK1/2 were all decreased compared with the control group stimulated with EGF. However, the protein expression levels of proapoptotic protein Bax and cleaved caspase-3 were increased. These results implied that cordycepin could inhibit cell proliferation and induce apoptosis via the EGFR signaling pathway. Our results indicated that there was potential to seek a novel EGFR inhibitor from cordycepin and its chemical derivatives.

  10. Inhibition of autophagy stimulate molecular iodine-induced apoptosis in hormone independent breast tumors

    SciTech Connect

    Singh, Preeti; Godbole, Madan; Rao, Geeta; Annarao, Sanjay; Mitra, Kalyan; Roy, Raja; Ingle, Arvind; Agarwal, Gaurav; Tiwari, Swasti

    2011-11-11

    Highlights: Black-Right-Pointing-Pointer Molecular iodine (I{sub 2}) causes non-apoptotic cell death in MDA-MB231 breast tumor cells. Black-Right-Pointing-Pointer Autophagy is activated as a survival mechanism in response to I{sub 2} in MDA-MB231. Black-Right-Pointing-Pointer Autophagy inhibition sensitizes tumor cells to I{sub 2}-induced apoptotic cell death. Black-Right-Pointing-Pointer Autophagy inhibitor potentiates apoptosis and tumor regressive effects of I{sub 2} in mice. -- Abstract: Estrogen receptor negative (ER{sup -ve}) and p53 mutant breast tumors are highly aggressive and have fewer treatment options. Previously, we showed that molecular Iodine (I{sub 2}) induces apoptosis in hormone responsive MCF-7 breast cancer cells, and non-apoptotic cell death in ER{sup -ve}-p53 mutant MDA-MB231 cells (Shrivastava, 2006). Here we show that I{sub 2} (3 {mu}M) treatment enhanced the features of autophagy in MDA-MB231 cells. Since autophagy is a cell survival response to most anti-cancer therapies, we used both in vitro and in vivo systems to determine whether ER{sup -ve} mammary tumors could be sensitized to I{sub 2}-induced apoptosis by inhibiting autophagy. Autophagy inhibition with chloroquine (CQ) and inhibitors for PI3K (3MA, LY294002) and H+/ATPase (baflomycin) resulted in enhanced cell death in I{sub 2} treated MDA-MB231 cells. Further, CQ (20 {mu}M) in combination with I{sub 2}, showed apoptotic features such as increased sub-G1 fraction ({approx}5-fold), expression of cleaved caspase-9 and -3 compared to I{sub 2} treatment alone. Flowcytometry of I{sub 2} and CQ co-treated cells revealed increase in mitochondrial membrane permeability (p < 0.01) and translocation of cathepsin D activity to cytosol relative to I{sub 2} treatment. For in vivo studies ICRC mice were transplanted subcutaneously with MMTV-induced mammary tumors. A significant reduction in tumor volumes, as measured by MRI, was found in I{sub 2} and CQ co-treated mice relative to I{sub 2} or

  11. Intense picosecond pulsed electric fields inhibit proliferation and induce apoptosis of HeLa cells.

    PubMed

    Zhang, Min; Xiong, Zheng-Ai; Chen, Wen-Juan; Yao, Cheng-Guo; Zhao, Zhong-Yong; Hua, Yuan-Yuan

    2013-06-01

    A picosecond pulsed electric field (psPEF) is a localized physical therapy for tumors that has been developed in recent years, and that may in the future be utilized as a targeted non‑invasive treatment. However, there are limited studies regarding the biological effects of psPEF on cells. Electric field amplitude and pulse number are the main parameters of psPEF that influence its biological effects. In this study, we exposed HeLa cells to a psPEF with a variety of electric field amplitudes, from 100 to 600 kV/cm, and various pulse numbers, from 1,000 to 3,000. An MTT assay was used to detect the growth inhibition, while flow cytometry was used to determine the occurrence of apoptosis and the cell cycle of the HeLa cells following treatment. The morphological changes during cell apoptosis were observed using transmission electron microscopy (TEM). The results demonstrated that the cell growth inhibition rate gradually increased, in correlation with the increasing electric field amplitude and pulse number, and achieved a plateau of maximum cell inhibition 12 h following the pulses. In addition, typical characteristics of HeLa cell apoptosis in the experimental groups were observed by TEM. The results demonstrated that the rate of apoptosis in the experimental groups was significantly elevated in comparison with the untreated group. In the treatment groups, the rate of apoptosis was greater in the higher amplitude groups than in the lower amplitude groups. The same results were obtained when the variable was the pulse number. Flow cytometric analysis indicated that the cell cycle of the HeLa cells was arrested at the G2/M phase following psPEF treatment. Overall, our results indicated that psPEF inhibited cell proliferation and induced cell apoptosis, and that these effects occurred in a dose-dependent manner. In addition, the results demonstrated that the growth of the HeLa cells was arrested at the G2/M phase following treatment. This study may provide a

  12. Carvacrol inhibits proliferation and induces apoptosis in human colon cancer cells.

    PubMed

    Fan, Kai; Li, Xiaolei; Cao, Yonggang; Qi, Hanping; Li, Lei; Zhang, Qianhui; Sun, Hongli

    2015-09-01

    Colon cancer is one of the most common malignancies worldwide and has a high mortality rate. Carvacrol is a major component of oregano and thyme essential oils and shows antitumor properties. Here, we investigated the effects of carvacrol on the proliferation and apoptosis of two human colon cancer cell lines, HCT116 and LoVo, and studied the molecular mechanisms of its antitumor properties. We found that carvacrol inhibited the proliferation and migration of the two colon cancer cell lines in a concentration-dependent manner. Cell invasion was suppressed after carvacrol treatment by decreasing the expression of matrix metalloprotease-2 (MMP-2) and MMP-9. Carvacrol treatment also caused cell cycle arrest in the G2/M phase and decreased cyclin B1 expression. Finally, carvacrol induced cell apoptosis in a dose-dependent manner. At the molecular level, carvacrol downregulated the expression of Bcl-2 and induced the phosphorylation of the extracellular-regulated protein kinase and protein kinase B (p-Akt). In parallel, carvacrol upregulated the expression of Bax and c-Jun N-terminal kinase. These results indicate that carvacrol might induce apoptosis in colon cancer cells through the mitochondrial apoptotic pathway and the MAPK and PI3K/Akt signaling pathways. Together, our results suggest that carvacrol may have therapeutic potential for the prevention and treatment of colon cancer.

  13. Telmisartan ameliorates cisplatin-induced nephrotoxicity by inhibiting MAPK mediated inflammation and apoptosis.

    PubMed

    Malik, Salma; Suchal, Kapil; Gamad, Nanda; Dinda, Amit Kumar; Arya, Dharamvir Singh; Bhatia, Jagriti

    2015-02-05

    Nephrotoxicity is a major adverse effect of the widely used anticancer drug cisplatin. Oxidative stress, inflammation and apoptosis are implicated in the pathophysiology of cisplatin-induced acute renal injury. Moreover, cisplatin activates many signal transduction pathways involved in cell injury and death, particularly mitogen activated protein kinase (MAPK) pathway. With this background, we aimed to investigate the protective effect of telmisartan, a widely used antihypertensive drug, in cisplatin-induced nephrotoxicity model in rats. To accomplish this, male albino wistar rats (150-200 g) were divided into 6 groups: Normal, cisplatin-control, telmisartan (2.5, 5 and 10 mg/kg) and telmisartan per se treatment groups. Normal saline or telmisartan was administered orally to rats for 10 days and cisplatin was given on 7th day (8 mg/kg; i.p.) to induce nephrotoxicity. On 10th day, rats were killed and both the kidneys were harvested for biochemical, histopathological and molecular studies. Cisplatin injected rats showed depressed renal function, altered proxidant-antioxidant balance and acute tubular necrosis which was significantly normalized by telmisartan co-treatment. Furthermore, cisplatin administration activated MAPK pathway that caused tubular inflammation and apoptosis in rats. Telmisartan treatment significantly prevented MAPK mediated inflammation and apoptosis. Among the three doses studied telmisartan at 10 mg/kg dose showed maximum nephroprotective effect which could be due to maintenance of cellular redox status and inhibition of MAPK activation.

  14. Syzygium cumini inhibits growth and induces apoptosis in cervical cancer cell lines: a primary study

    PubMed Central

    Barh, D; Viswanathan, G

    2008-01-01

    Cervical cancer is common among women in the Indian subcontinent and the incidences and death rates are gradually increasing over the years. Several dietary phytochemicals have been reported to have growth inhibitory and apoptotic effect on HeLa and other cervical cell lines. In this study, using Hoechst 33342 staining, MTT, Annexin V-FLUOS/PI and TUNEL assays we demonstrated that Syzygium cumini extract inhibits the growth and induces apoptosis in HeLa and SiHa cervical cancer cell lines in a dose- and time-dependent manner. The phytochemical, its mode of action and safety issues are yet to be determined. PMID:22275971

  15. Syzygium cumini inhibits growth and induces apoptosis in cervical cancer cell lines: a primary study.

    PubMed

    Barh, D; Viswanathan, G

    2008-01-01

    Cervical cancer is common among women in the Indian subcontinent and the incidences and death rates are gradually increasing over the years. Several dietary phytochemicals have been reported to have growth inhibitory and apoptotic effect on HeLa and other cervical cell lines. In this study, using Hoechst 33342 staining, MTT, Annexin V-FLUOS/PI and TUNEL assays we demonstrated that Syzygium cumini extract inhibits the growth and induces apoptosis in HeLa and SiHa cervical cancer cell lines in a dose- and time-dependent manner. The phytochemical, its mode of action and safety issues are yet to be determined.

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

    PubMed Central

    Wang, Baocheng; Wang, Jiajia; Li, Qifeng; Meng, Wei

    2016-01-01

    Oxymatrine (OMT), an alkaloid derived from the traditional Chinese medicine herb Sophora flavescens Aiton, has been shown to exhibit anticancer properties on various types of cancer cells. In this study, we investigate the anticancer properties of OMT on human glioblastoma (GBM) cells and evaluate their underlying mechanisms. MTT assays were performed and demonstrated that OMT significantly inhibits the proliferation of GBM cells. Flow cytometry suggested that OMT at a concentration of 10−5 M may induce apoptosis in U251 and A172 cells. Western blot analyses demonstrated a significant increase in the expression of Bax and caspase-3 and a significant decrease in expression of Bcl-2 in both U251 and A172 cells. Additionally, OMT was found by transwell and high-content screening assays to decrease the migratory ability of the evaluated GBM cells. These findings suggest that the antitumor effects of OMT may be the result of inhibition of cell proliferation and migration and the induction of apoptosis by regulating the expression of apoptosis-associated proteins. OMT may represent a novel anticancer therapy for the treatment of GBM. PMID:27957488

  17. Steroid receptor coactivator-interacting protein (SIP) inhibits caspase-independent apoptosis by preventing apoptosis-inducing factor (AIF) from being released from mitochondria.

    PubMed

    Wang, Dandan; Liang, Jing; Zhang, Yu; Gui, Bin; Wang, Feng; Yi, Xia; Sun, Luyang; Yao, Zhi; Shang, Yongfeng

    2012-04-13

    Apoptosis-inducing factor (AIF) is a caspase-independent death effector. Normally residing in the mitochondrial intermembrane space, AIF is released and translocated to the nucleus in response to proapoptotic stimuli. Nuclear AIF binds to DNA and induces chromatin condensation and DNA fragmentation, characteristics of apoptosis. Until now, it remained to be clarified how the mitochondrial-nuclear translocation of AIF is regulated. Here we report that steroid receptor coactivator-interacting protein (SIP) interacts directly with AIF in mitochondria and specifically inhibits caspase-independent and AIF-dependent apoptosis. Challenging cells with apoptotic stimuli leads to rapid degradation of SIP, and subsequently AIF is liberated from mitochondria and translocated to the nucleus to induce apoptosis. Together, our data demonstrate that SIP is a novel regulator in caspase-independent and AIF-mediated apoptosis.

  18. Beetroot red (betanin) inhibits vinyl carbamate- and benzo(a)pyrene-induced lung tumorigenesis through apoptosis.

    PubMed

    Zhang, Qi; Pan, Jing; Wang, Yian; Lubet, Ronald; You, Ming

    2013-09-01

    Betanin, also called beetroot red, has been extensively used as a food colorant. In this study, the chemopreventive activity of betanin by oral consumption was investigated in two mouse lung tumor models. Vinyl carbamate (VC) and benzo(a)pyrene (B(a)P) were used to induce lung tumors, and female A/J mice were treated with betanin in drinking water. Betanin significantly decreased tumor multiplicity and tumor load induced by both carcinogens. Tumor multiplicity and tumor load were decreased by 20% and 39% in the VC lung model, and by 46% and 65% in the B(a)P lung model, respectively. Betanin reduced the number of CD31+ endothelial microvessels and increased the expression of caspase-3, suggesting that the lung tumor inhibitory effects were through induction of apoptosis and inhibition of angiogenesis. Betanin also induced apoptosis through activated caspase-3, -7, -9, and PARP in human lung cancer cell lines. Our data show that betanin significantly inhibits lung tumorigenesis in A/J mice and merits investigation as a chemopreventive agent for human lung cancer.

  19. Inhibition of Nicotinamide Phosphoribosyltransferase Induces Apoptosis in Estrogen Receptor-Positive MCF-7 Breast Cancer Cells

    PubMed Central

    Alaee, Mohammad; Khaghani, Shahnaz; Behroozfar, Kiarash; Hesari, Zahra; Ghorbanhosseini, Seyedeh Sara

    2017-01-01

    Purpose Tumor cells have increased turnover of nicotinamide adenine dinucleotide (NAD+), the main coenzyme in processes including adenosine diphosphate-ribosylation, deacetylation, and calcium mobilization. NAD+ is predominantly synthesized in human cells via the salvage pathway, with the first component being nicotinamide. Nicotinamide phosphoribosyltransferase (NAMPT) is the key enzyme in this pathway, and its chemical inhibition by FK866 has elicited antitumor effects in several preclinical models of solid and hematologic cancers. However, its efficacy in estrogen receptor (ER)-positive and human epidermal growth factor receptor 2-positive breast cancer cells has not been previously investigated. In this study, we aimed to deplete the NAD+ content of MCF-7 cells, a model cell line for ER-positive breast cancer, by inhibiting NAMPT in order to evaluate downstream effects on p53 and its acetylation, p21 and Bcl-2-associated X protein (BAX) expression, and finally, apoptosis in MCF-7 breast cancer cells. Methods MCF-7 cells were cultured and treated with FK866. NAD+ levels in cells were determined colorimetrically. Levels of p53 and its acetylated form were determined by Western blotting. Expression of p21 and BAX was determined by real-time polymerase chain reaction. Finally, levels of apoptosis were assessed by flow cytometry using markers for annexin V and propidium iodide. Results FK866 treatment was able to increase p53 levels and acetylation, upregulate BAX and p21 expression, and induce apoptosis in MCF-7 cells. Addition of exogenous NAD+ to cells reversed these effects, suggesting that FK866 exerted its effects by depleting NAD+ levels. Conclusion Results showed that FK866 could effectively inhibit NAD+ biosynthesis and induce programmed cell death in MCF-7 cells, suggesting that NAMPT inhibitors may be useful for the treatment of ER-positive breast cancers. PMID:28382091

  20. MicroRNA-212 inhibits hepatocellular carcinoma cell proliferation and induces apoptosis by targeting FOXA1

    PubMed Central

    Tu, Huahua; Wei, Gang; Cai, Qinghe; Chen, Xianxiang; Sun, Zequn; Cheng, Caitao; Zhang, Linfei; Feng, Yong; Zhou, Huadong; Zhou, Bo; Zeng, Tiancai

    2015-01-01

    MircroRNA-212 (miR-212) is proposed as a novel tumor-related miRNA and has been found to be significantly deregulated in human cancers. In this study, the miR-212 expression was found to be obviously downregulated in hepatocellular carcinoma (HCC) tissues as compared with adjacent nontumor tissues. Clinical association analysis indicated that low expression of miR-212 was prominently correlated with poor prognostic features of HCC, including high AFP level, large tumor size, high Edmondson-Steiner grading, and advanced tumor-node-metastasis tumor stage. Furthermore, the miR-212 expression was an independent prognostic marker for predicting both 5-year overall survival and disease-free survival of HCC patients. Our in vitro studies showed that upregulation of miR-212 inhibited cell proliferation and induced apoptosis in HepG2 cells. On the contrary, downregulation of miR-212 promoted cell proliferation and suppressed apoptosis in Huh7 cells. Interestingly, we found that upregulation of miR-212 decreased FOXA1 expression in HepG2 cells. Significantly, FOXA1 was identified as a direct target of miR-212 in HCC. FOXA1 was downregulated in HCC tissues as compared with noncancerous tissues. An inverse correlation between FOXA1 and miR-212 expression was observed in HCC tissues. Notably, FOXA1 knockdown inhibited cell proliferation and induced apoptosis in HepG2 cells. In conclusion, miR-212 is a potent prognostic marker and may suppress HCC tumor growth by inhibiting FOXA1 expression. PMID:26347321

  1. Hydrogen sulfide inhibits rotenone-induced apoptosis via preservation of mitochondrial function.

    PubMed

    Hu, Li-Fang; Lu, Ming; Wu, Zhi-Yuan; Wong, Peter T-H; Bian, Jin-Song

    2009-01-01

    Hydrogen sulfide (H(2)S) has been proposed as a novel neuromodulator, which plays critical roles in the central nervous system affecting both neurons and glial cells. However, its relationship with neurodegenerative diseases is unexplored. The present study was undertaken to investigate the effects of H(2)S on cell injury induced by rotenone, a commonly used toxin in establishing in vivo and in vitro Parkinson's disease (PD) models, in human-derived dopaminergic neuroblastoma cell line (SH-SY5Y). We report here that sodium hydrosulfide (NaHS), an H(2)S donor, concentration-dependently suppressed rotenone-induced cellular injury and apoptotic cell death. NaHS also prevented rotenone-induced p38- and c-Jun NH(2)-terminal kinase (JNK)-mitogen-activated protein kinase (MAPK) phosphorylation and rotenone-mediated changes in Bcl-2/Bax levels, mitochondrial membrane potential (DeltaPsi(m)) dissipation, cytochrome c release, caspase-9/3 activation and poly(ADP-ribose) polymerase cleavage. Furthermore, 5-hydroxydecanoate, a selective blocker of mitochondrial ATP-sensitive potassium (mitoK(ATP)) channel, attenuated the protective effects of NaHS against rotenone-induced cell apoptosis. Thus, we demonstrated for the first time that H(2)S inhibited rotenone-induced cell apoptosis via regulation of mitoK(ATP) channel/p38- and JNK-MAPK pathway. Our data suggest that H(2)S may have potential therapeutic value for neurodegenerative diseases, such as PD.

  2. Glucocorticoid receptor activation inhibits p53-induced apoptosis of MCF10Amyc cells via induction of protein kinase Cε.

    PubMed

    Aziz, Moammir H; Shen, Hong; Maki, Carl G

    2012-08-24

    Glucocorticoid receptor (GR) is a ligand-dependent transcription factor that can promote apoptosis or survival in a cell-specific manner. Activated GR has been reported to inhibit apoptosis in mammary epithelial cells and breast cancer cells by increasing pro-survival gene expression. In this study, activated GR inhibited p53-dependent apoptosis in MCF10A cells and human mammary epithelial cells that overexpress the MYC oncogene. Specifically, GR agonists hydrocortisone or dexamethasone inhibited p53-dependent apoptosis induced by cisplatin, ionizing radiation, or the MDM2 antagonist Nutlin-3. In contrast, the GR antagonist RU486 sensitized the cells to apoptosis by these agents. Apoptosis inhibition was associated with maintenance of mitochondrial membrane potential, diminished caspase-3 and -7 activation, and increased expression at both the mRNA and protein level of the anti-apoptotic PKC family member PKCε. Knockdown of PKCε via siRNA targeting reversed the protective effect of dexamethasone and restored apoptosis sensitivity. These data provide evidence that activated GR can inhibit p53-dependent apoptosis through induction of the anti-apoptotic factor PKCε.

  3. Neurotrophin-3 production promotes human neuroblastoma cell survival by inhibiting TrkC-induced apoptosis

    PubMed Central

    Bouzas-Rodriguez, Jimena; Cabrera, Jorge Ruben; Delloye-Bourgeois, Céline; Ichim, Gabriel; Delcros, Jean-Guy; Raquin, Marie-Anne; Rousseau, Raphaël; Combaret, Valérie; Bénard, Jean; Tauszig-Delamasure, Servane; Mehlen, Patrick

    2010-01-01

    Tropomyosin-related kinase receptor C (TrkC) is a neurotrophin receptor with tyrosine kinase activity that was expected to be oncogenic. However, it has several characteristics of a tumor suppressor: its expression in tumors has often been associated with good prognosis; and it was recently demonstrated to be a dependence receptor, transducing different positive signals in the presence of ligand but inducing apoptosis in the absence of ligand. Here we show that the TrkC ligand neurotrophin-3 (NT-3) is upregulated in a large fraction of aggressive human neuroblastomas (NBs) and that it blocks TrkC-induced apoptosis of human NB cell lines, consistent with the idea that TrkC is a dependence receptor. Functionally, both siRNA knockdown of NT-3 expression and incubation with a TrkC-specific blocking antibody triggered apoptosis in human NB cell lines. Importantly, disruption of the NT-3 autocrine loop in malignant human neuroblasts triggered in vitro NB cell death and inhibited tumor growth and metastasis in both a chick and a mouse xenograft model. Thus, we believe that our data suggest that NT-3/TrkC disruption is a putative alternative targeted therapeutic strategy for the treatment of NB. PMID:20160348

  4. Sorafenib Enhances Radiation-Induced Apoptosis in Hepatocellular Carcinoma by Inhibiting STAT3

    SciTech Connect

    Huang, Chao-Yuan; Lin, Chen-Si; Tai, Wei-Tien; Hsieh, Chi-Ying; Shiau, Chung-Wai; Cheng, Ann-Lii; Chen, Kuen-Feng

    2013-07-01

    Purpose: Hepatocellular carcinoma (HCC) is one of the most common and lethal human malignancies. Lack of efficient therapy for advanced HCC is a pressing problem worldwide. This study aimed to determine the efficacy and mechanism of combined sorafenib and radiation therapy treatment for HCC. Methods and Materials: HCC cell lines (PLC5, Huh-7, Sk-Hep1, and Hep3B) were treated with sorafenib, radiation, or both, and apoptosis and signal transduction were analyzed. Results: All 4 HCC cell lines showed resistance to radiation-induced apoptosis; however, this resistance could be reversed in the presence of sorafenib. Inhibition of phospho-STAT3 was found in cells treated with sorafenib or sorafenib plus radiation and subsequently reduced the expression levels of STAT3-related proteins, Mcl-1, cyclin D1, and survivin. Silencing STAT3 by RNA interference overcame apoptotic resistance to radiation in HCC cells, and the ectopic expression of STAT3 in HCC cells abolished the radiosensitizing effect of sorafenib. Moreover, sorafenib plus radiation significantly suppressed PLC5 xenograft tumor growth. Conclusions: These results indicate that sorafenib sensitizes resistant HCC cells to radiation-induced apoptosis via downregulating phosphorylation of STAT3 in vitro and in vivo.

  5. TAZ promotes cell growth and inhibits Celastrol-induced cell apoptosis.

    PubMed

    Wang, Shuren; Ma, Kai; Chen, Lechuang; Zhu, Hongxia; Liang, Shufang; Liu, Mei; Xu, Ningzhi

    2016-10-01

    Hippo pathway is a highly conservative signalling pathway related to the development of organisms, which has been demonstrated to be strongly linked to the tumorigenesis and tumour progression. As the major downstream effector of Hippo pathway, yes-associated protein (YAP), is a transcriptional activator of target genes that are involved in cell proliferation and survival. As an oncogene, YAP can promote cell growth and inhibit cell apoptosis. Another major downstream effector of Hippo pathway, transcriptional co-activators with PDZ-binding motif (TAZ), is nearly 60% homologous with YAP. In the present study, we assume that TAZ probably has the similar function to YAP. To test this issue, we established an inducible and a stable expression system of TAZ in T-Rex-293 and HEK293 cells respectively. The results of cell growth curves, colony formation assay and tumour xenograft growth showed that overexpression of TAZ could promote cell growth in vitro and in vivo Meanwhile, we found that up-regulated expression of TAZ could partially restore Celastrol-induced cell apoptosis. Induced overexpression of TAZ could up-regulate its target genes including ankyrin repeat domain-containing protein (ANKRD), cysteine-rich 61 (CYR61) and connective tissue growth factor (CTGF), increase the expression of B-cell lymphoma-2 (Bcl-2), decrease the expression of Bcl-2 associated X protein (Bax) and activate the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) pathway, which may be the mechanism underlying anti-apoptosis of TAZ. All these findings indicated that TAZ acts as an oncogene that could be a key regulator of cell proliferation and apoptosis.

  6. TAZ promotes cell growth and inhibits Celastrol-induced cell apoptosis

    PubMed Central

    Wang, Shuren; Ma, Kai; Chen, Lechuang; Zhu, Hongxia; Liang, Shufang; Liu, Mei; Xu, Ningzhi

    2016-01-01

    Hippo pathway is a highly conservative signalling pathway related to the development of organisms, which has been demonstrated to be strongly linked to the tumorigenesis and tumour progression. As the major downstream effector of Hippo pathway, yes-associated protein (YAP), is a transcriptional activator of target genes that are involved in cell proliferation and survival. As an oncogene, YAP can promote cell growth and inhibit cell apoptosis. Another major downstream effector of Hippo pathway, transcriptional co-activators with PDZ-binding motif (TAZ), is nearly 60% homologous with YAP. In the present study, we assume that TAZ probably has the similar function to YAP. To test this issue, we established an inducible and a stable expression system of TAZ in T-Rex-293 and HEK293 cells respectively. The results of cell growth curves, colony formation assay and tumour xenograft growth showed that overexpression of TAZ could promote cell growth in vitro and in vivo. Meanwhile, we found that up-regulated expression of TAZ could partially restore Celastrol-induced cell apoptosis. Induced overexpression of TAZ could up-regulate its target genes including ankyrin repeat domain-containing protein (ANKRD), cysteine-rich 61 (CYR61) and connective tissue growth factor (CTGF), increase the expression of B-cell lymphoma-2 (Bcl-2), decrease the expression of Bcl-2 associated X protein (Bax) and activate the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) pathway, which may be the mechanism underlying anti-apoptosis of TAZ. All these findings indicated that TAZ acts as an oncogene that could be a key regulator of cell proliferation and apoptosis. PMID:27515420

  7. Humic acid inhibits HBV-induced autophagosome formation and induces apoptosis in HBV-transfected Hep G2 cells

    PubMed Central

    Pant, Kishor; Yadav, Ajay K.; Gupta, Parul; Rathore, Abhishek Singh; Nayak, Baibaswata; Venugopal, Senthil K.

    2016-01-01

    Hepatitis B Virus (HBV) utilizes several mechanisms to survive in the host cells and one of the main pathways being autophagosome formation. Humic acid (HA), one of the major components of Mineral pitch, is an Ayurvedic medicinal food, commonly used by the people of the Himalayan regions of Nepal and India for various body ailments. We hypothesized that HA could induce cell death and inhibit HBV-induced autophagy in hepatic cells. Incubation of Hep G2.2.1.5 cells (HepG2 cells stably expressing HBV) with HA (100 μM) inhibited both cell proliferation and autophagosome formation significantly, while apoptosis induction was enhanced. Western blot results showed that HA incubation resulted in decreased levels of beclin-1, SIRT-1 and c-myc, while caspase-3 and β-catenin expression were up-regulated. Western blot results showed that HA significantly inhibited the expression of HBx (3-fold with 50 μM and 5-fold with 100 μM) compared to control cells. When HA was incubated with HBx-transfected Hep G2 cells, HBx-induced autophagosome formation and beclin-1 levels were decreased. These data showed that HA induced apoptosis and inhibited HBV-induced autophagosome formation and proliferation in hepatoma cells. PMID:27708347

  8. Inhibition of PKR protects against H2O2-induced injury on neonatal cardiac myocytes by attenuating apoptosis and inflammation

    PubMed Central

    Wang, Yongyi; Men, Min; Xie, Bo; Shan, Jianggui; Wang, Chengxi; Liu, Jidong; Zheng, Hui; Yang, Wengang; Xue, Song; Guo, Changfa

    2016-01-01

    Reactive oxygenation species (ROS) generated from reperfusion results in cardiac injury through apoptosis and inflammation, while PKR has the ability to promote apoptosis and inflammation. The aim of the study was to investigate whether PKR is involved in hydrogen peroxide (H2O2) induced neonatal cardiac myocytes (NCM) injury. In our study, NCM, when exposed to H2O2, resulted in persistent activation of PKR due to NCM endogenous RNA. Inhibition of PKR by 2-aminopurine (2-AP) or siRNA protected against H2O2 induced apoptosis and injury. To elucidate the mechanism, we revealed that inhibition of PKR alleviated H2O2 induced apoptosis companied by decreased caspase3/7 activity, BAX and caspase-3 expression. We also revealed that inhibition of PKR suppressed H2O2 induced NFκB pathway and NLRP3 activation. Finally, we found ADAR1 mRNA and protein expression were both induced after H2O2 treatment through STAT-2 dependent pathway. By gain and loss of ADAR1 expression, we confirmed ADAR1 modulated PKR activity. Therefore, we concluded inhibition of PKR protected against H2O2-induced injury by attenuating apoptosis and inflammation. A self-preservation mechanism existed in NCM that ADAR1 expression is induced by H2O2 to limit PKR activation simultaneously. These findings identify a novel role for PKR/ADAR1 in myocardial reperfusion injury. PMID:27929137

  9. Alantolactone Induces Apoptosis in HepG2 Cells through GSH Depletion, Inhibition of STAT3 Activation, and Mitochondrial Dysfunction

    PubMed Central

    Khan, Muhammad; Li, Ting; Ahmad Khan, Muhammad Khalil; Rasul, Azhar; Nawaz, Faisal; Sun, Meiyan; Zheng, Yongchen; Ma, Tonghui

    2013-01-01

    Signal transducer and activator of transcription 3 (STAT3) constitutively expresses in human liver cancer cells and has been implicated in apoptosis resistance and tumorigenesis. Alantolactone, a sesquiterpene lactone, has been shown to possess anticancer activities in various cancer cell lines. In our previous report, we showed that alantolactone induced apoptosis in U87 glioblastoma cells via GSH depletion and ROS generation. However, the molecular mechanism of GSH depletion remained unexplored. The present study was conducted to envisage the molecular mechanism of alantolactone-induced apoptosis in HepG2 cells by focusing on the molecular mechanism of GSH depletion and its effect on STAT3 activation. We found that alantolactone induced apoptosis in HepG2 cells in a dose-dependent manner. This alantolactone-induced apoptosis was found to be associated with GSH depletion, inhibition of STAT3 activation, ROS generation, mitochondrial transmembrane potential dissipation, and increased Bax/Bcl-2 ratio and caspase-3 activation. This alantolactone-induced apoptosis and GSH depletion were effectively inhibited or abrogated by a thiol antioxidant, N-acetyl-L-cysteine (NAC). The data demonstrate clearly that intracellular GSH plays a central role in alantolactone-induced apoptosis in HepG2 cells. Thus, alantolactone may become a lead chemotherapeutic candidate for the treatment of liver cancer. PMID:23533997

  10. Bufalin Inhibits Proliferation and Induces Apoptosis in Osteosarcoma Cells by Downregulating MicroRNA-221

    PubMed Central

    Han, Kun; Wang, Yaling

    2016-01-01

    Bufalin, a major component of the Chinese medicine ChanSu, which is prepared from the skin and parotid venom glands of toads, has shown cytotoxicity in several malignant tumors. Here, we reported that bufalin inhibited proliferation and induced mitochondria-dependent apoptosis in U-2OS and Saos-2 osteosarcoma cells with intracellular reactive oxygen species (ROS) production. By microRNA (miR) array analysis and quantitative reverse transcription polymerase chain reaction, we found that miR-221 was downregulated after treatment with bufalin. In accordance with TargetScan prediction and luciferase reporter assay, Bcl2 binding component 3 (BBC3) was the direct target of miR-221. Furthermore, upregulating miR-221 by its MIMIC and suppressing BBC3 by small interfering RNA (siRNA) reversed the effects of bufalin on osteosarcoma cells. Collectively, our data indicate that bufalin inhibits cell proliferation and induces mitochondria-dependent apoptosis in osteosarcoma cells through downregulating miR-221 and triggering BBC3 expression. PMID:28074104

  11. miR-101 inhibits autophagy and enhances cisplatin-induced apoptosis in hepatocellular carcinoma cells.

    PubMed

    Xu, Yonghua; An, Yong; Wang, Yun; Zhang, Changhe; Zhang, Hai; Huang, Changjun; Jiang, Hao; Wang, Xuehao; Li, Xiangcheng

    2013-05-01

    Hepatocellular carcinoma (HCC) ranks third in cancer-related mortality due to late diagnosis and poor treatment options. Autophagy is a lysosome-mediated protein and organelle degradation process which is characterized by the formation of double-membrane vesicles, known as autophagosomes. Increasing evidence reveals that autophagy functions as a survival mechanism in liver cancer cells against drug-induced apoptosis. In this study, we found that autophagy was suppressed by miR-101 in the HCC cell line HepG2. miR-101 inhibited autophagy via targets including RAB5A, STMN1 and ATG4D. Moreover, miR-101 enhanced apoptosis induced by cisplatin in the HepG2 cell line. The possible mechanism of this effect may be through inhibition of autophagy. Our results indicate a novel and critical role for miR-101 and autophagy in the chemoresistance of cisplatin in HCC. We propose that gene therapy targeting miR-101/autophagy should be investigated further as a potential alternative therapeutic strategy for HCC.

  12. Noscapine inhibits human hepatocellular carcinoma growth through inducing apoptosis in vitro and in vivo.

    PubMed

    Xu, G; Niu, Z; Dong, J; Zhao, Y; Zhang, Y; Li, X

    2016-01-01

    Noscapine, a phthalideisoquinoline alkaloid derived from opium, has been demonstrated as a promising anti-tumor compound against various cancers. However, the anti-cancer activity of noscapine in hepatocellular carcinoma has not been defined. In this study, we investigate the inhibitive effects of noscapine on human hepatocellular carcinoma (HCC) using both in vitro and in vivo models. In vitro proliferation assay showed that noscapine suppressed HepG2 and Huh7 cells in dose- and time-dependent manners. With a mouse xenograft model, noscapine showed notable inhibition on HCC tumor growth in vivo without suppression of body weight. Moreover, apoptotic induction and regulation of related signalings by noscapine were examined by nuclear DNA staining, TUNEL, and western blotting assays. Results showed that noscapine induced apoptosis in HCC cells both in vitro and in vivo. Further studies indicated that noscapine induced antive-capsase-3, cleavage PARP, and decreased the ratio of Bcl-2/Bax. Hence, these data indicates that noscapine selectively suppresses HCC cell growth through apoptosis induction, providing evidence for application of noscapine as a novel agent against human hepatocellular carcinoma.

  13. Ku70 inhibits gemcitabine-induced DNA damage and pancreatic cancer cell apoptosis.

    PubMed

    Ma, Jiali; Hui, Pingping; Meng, Wenying; Wang, Na; Xiang, Shihao

    2017-03-18

    The current study focused on the role of Ku70, a DNA-dependent protein kinase (DNA-PK) complex protein, in pancreatic cancer cell resistance to gemcitabine. In both established cell lines (Mia-PaCa-2 and PANC-1) and primary human pancreatic cancer cells, shRNA/siRNA-mediated knockdown of Ku70 significantly sensitized gemcitabine-induced cell death and proliferation inhibition. Meanwhile, gemcitabine-induced DNA damage and subsequent pancreatic cancer cell apoptosis were also potentiated with Ku70 knockdown. On the other hand, exogenous overexpression of Ku70 in Mia-PaCa-2 cells suppressed gemcitabine-induced DNA damage and subsequent cell apoptosis. In a severe combined immune deficient (SCID) mice Mia-PaCa-2 xenograft model, gemcitabine-induced anti-tumor activity was remarkably pontificated when combined with Ku70 shRNA knockdown in the xenografts. The results of this preclinical study imply that Ku70 might be a primary resistance factor of gemcitabine, and Ku70 silence could significantly chemo-sensitize gemcitabine in pancreatic cancer cells.

  14. Piperlongumine induces apoptosis and reduces bortezomib resistance by inhibiting STAT3 in multiple myeloma cells

    PubMed Central

    Xia, Dandan; Zhao, Kai; Zeng, Lingyu; Yao, Ruosi; Zhang, Ying; Li, Zhenyu; Niu, Mingshan; Xu, Kailin

    2016-01-01

    Effective new therapies are urgently needed for the treatment of multiple myeloma (MM), an incurable hematological malignancy. In this study, we evaluated the effects of piperlongumine on MM cell proliferation both in vivo and in vitro. Piperlongumine inhibited the proliferation of MM cells by inducing cell apoptosis and blocking osteoclastogenesis. Notably, piperlongumine also reduced bortezomib resistance in MM cells. In a disseminated MM mouse model, piperlongumine prolonged the survival of tumor-bearing mice without causing any obvious toxicity. Mechanistically, piperlongumine inhibited the STAT3 signal pathway in MM cells by binding directly to the STAT3 Cys712 residue. These findings suggest that the clinical use of piperlongumine to overcome bortezomib resistance in MM should be evaluated. PMID:27634873

  15. Fatty acid synthase inhibitors induce apoptosis in non-tumorigenic melan-a cells associated with inhibition of mitochondrial respiration.

    PubMed

    Rossato, Franco A; Zecchin, Karina G; La Guardia, Paolo G; Ortega, Rose M; Alberici, Luciane C; Costa, Rute A P; Catharino, Rodrigo R; Graner, Edgard; Castilho, Roger F; Vercesi, Aníbal E

    2014-01-01

    The metabolic enzyme fatty acid synthase (FASN) is responsible for the endogenous synthesis of palmitate, a saturated long-chain fatty acid. In contrast to most normal tissues, a variety of human cancers overexpress FASN. One such cancer is cutaneous melanoma, in which the level of FASN expression is associated with tumor invasion and poor prognosis. We previously reported that two FASN inhibitors, cerulenin and orlistat, induce apoptosis in B16-F10 mouse melanoma cells via the intrinsic apoptosis pathway. Here, we investigated the effects of these inhibitors on non-tumorigenic melan-a cells. Cerulenin and orlistat treatments were found to induce apoptosis and decrease cell proliferation, in addition to inducing the release of mitochondrial cytochrome c and activating caspases-9 and -3. Transfection with FASN siRNA did not result in apoptosis. Mass spectrometry analysis demonstrated that treatment with the FASN inhibitors did not alter either the mitochondrial free fatty acid content or composition. This result suggests that cerulenin- and orlistat-induced apoptosis events are independent of FASN inhibition. Analysis of the energy-linked functions of melan-a mitochondria demonstrated the inhibition of respiration, followed by a significant decrease in mitochondrial membrane potential (ΔΨm) and the stimulation of superoxide anion generation. The inhibition of NADH-linked substrate oxidation was approximately 40% and 61% for cerulenin and orlistat treatments, respectively, and the inhibition of succinate oxidation was approximately 46% and 52%, respectively. In contrast, no significant inhibition occurred when respiration was supported by the complex IV substrate N,N,N',N'-tetramethyl-p-phenylenediamine (TMPD). The protection conferred by the free radical scavenger N-acetyl-cysteine indicates that the FASN inhibitors induced apoptosis through an oxidative stress-associated mechanism. In combination, the present results demonstrate that cerulenin and orlistat induce

  16. Fatty Acid Synthase Inhibitors Induce Apoptosis in Non-Tumorigenic Melan-A Cells Associated with Inhibition of Mitochondrial Respiration

    PubMed Central

    Rossato, Franco A.; Zecchin, Karina G.; La Guardia, Paolo G.; Ortega, Rose M.; Alberici, Luciane C.; Costa, Rute A. P.; Catharino, Rodrigo R.; Graner, Edgard; Castilho, Roger F.; Vercesi, Aníbal E.

    2014-01-01

    The metabolic enzyme fatty acid synthase (FASN) is responsible for the endogenous synthesis of palmitate, a saturated long-chain fatty acid. In contrast to most normal tissues, a variety of human cancers overexpress FASN. One such cancer is cutaneous melanoma, in which the level of FASN expression is associated with tumor invasion and poor prognosis. We previously reported that two FASN inhibitors, cerulenin and orlistat, induce apoptosis in B16-F10 mouse melanoma cells via the intrinsic apoptosis pathway. Here, we investigated the effects of these inhibitors on non-tumorigenic melan-a cells. Cerulenin and orlistat treatments were found to induce apoptosis and decrease cell proliferation, in addition to inducing the release of mitochondrial cytochrome c and activating caspases-9 and -3. Transfection with FASN siRNA did not result in apoptosis. Mass spectrometry analysis demonstrated that treatment with the FASN inhibitors did not alter either the mitochondrial free fatty acid content or composition. This result suggests that cerulenin- and orlistat-induced apoptosis events are independent of FASN inhibition. Analysis of the energy-linked functions of melan-a mitochondria demonstrated the inhibition of respiration, followed by a significant decrease in mitochondrial membrane potential (ΔΨm) and the stimulation of superoxide anion generation. The inhibition of NADH-linked substrate oxidation was approximately 40% and 61% for cerulenin and orlistat treatments, respectively, and the inhibition of succinate oxidation was approximately 46% and 52%, respectively. In contrast, no significant inhibition occurred when respiration was supported by the complex IV substrate N,N,N′,N′-tetramethyl-p-phenylenediamine (TMPD). The protection conferred by the free radical scavenger N-acetyl-cysteine indicates that the FASN inhibitors induced apoptosis through an oxidative stress-associated mechanism. In combination, the present results demonstrate that cerulenin and orlistat

  17. Amantadine inhibits cellular proliferation and induces the apoptosis of hepatocellular cancer cells in vitro.

    PubMed

    Lan, Zengmei; Chong, Zhaoyang; Liu, Cong; Feng, Danyang; Fang, Dihai; Zang, Weijin; Zhou, Jun

    2015-09-01

    Hepatocellular carcinoma (HCC) is one of the most aggressive malignancies worldwide, and its incidence associated with viral infection has increased in recent years. Amantadine is a tricyclic symmetric amine that can effectively protect against the hepatitis C virus. However, its antitumor properties remain unclear. In the present study, the effects of amantadine on tumor cell viability, cell cycle regulation and apoptosis were investigated. The growth of HepG2 and SMMC‑7721 cells (HCC cell lines) was detected by an MTT assay. Flow cytometry was used to investigate cell cycle regulation and apoptosis. Reverse transcription‑quantitative polymerase chain reaction and western blot analysis were also performed to examine the expression of cell cycle‑ and apoptosis‑related genes and proteins, including cyclin E, cyclin D1, cyclin‑dependent kinase 2 (CDK2), B‑cell lymphoma 2 (Bcl‑2) and Bax. Our results demonstrated that amantadine markedly inhibited the proliferation of HepG2 and SMMC‑7721 cells in a dose‑ and time‑dependent manner and arrested the cell cycle at the G0/G1 phase. The levels of the cell cycle‑related genes and proteins (cyclin D1, cyclin E and CDK2) were reduced by amantadine, and apoptosis was significantly induced. Amantadine treatment also reduced Bcl‑2 and increased the Bax protein and mRNA levels. Additionally, Bcl‑2/Bax ratios were lower in the two HCC cell lines following amantadine treatment. Collectively, these results emphasize the role of amantadine in suppressing proliferation and inducing apoptosis in HCC cells, advocating its use as a novel tumor-suppressive therapeutic candidate.

  18. Zinc inhibits apoptosis and maintains NEP downregulation, induced by ropivacaine, in HaCaT cells.

    PubMed

    Kontargiris, Evangelos; Vadalouka, Athina; Ragos, Vasilios; Kalfakakou, Vasiliki

    2012-12-01

    Zinc (Zn), a cell-protective metal against various toxic compounds, is the key agent for neutral endopeptidase (NEP) functional structure. NEP is a zinc metalloenzyme which degrades endogenous opioids and is expressed in human keratinocytes (HaCaT). Ropivacaine, a widely used opiate local anaesthetic, exerts cell toxic and apoptotic effects against HaCaT cells. The aim of the present study is to investigate whether zinc modulates the effects of ropivacaine on proliferation, viability, apoptosis and NEP expression in HaCaT cells. To investigate the role of ropivacaine in NEP function, HaCaT cells overexpressing NEP were generated via cell transfection with plasmids carrying NEP cDNA. Ropivacaine's anti-proliferative effect was tested by Neubauer's chamber cell counting, and induction of cell death was demonstrated by trypan blue exclusion assay. Apoptosis due to ropivacaine was tested via DNA fragmentation and poly-ADP-ribose-polymerase (PARP) cleavage. NEP and PARP expression was performed by western blot analysis. Results showed that zinc (15 μΜ) inhibited proliferation and cell death induction by ropivacaine (0.5, 1 and 2 mM) (p < 0.05) as well as apoptosis induced by the drug (0.5 and 1 mM) in HaCaT cells. Ropivacaine (1.0, 2.0 and 5.0 mM) downregulated NEP expression in the presence of zinc (15 μΜ) while NEP overexpression enhanced ropivacaine's apoptotic effect. In conclusion, the abilities of zinc to inhibit the toxic and apoptotic effects of ropivacaine, to maintain NEP downregulation induced by the drug and, consequently, to enhance its anaesthetic result suggest that zinc may have a significant role in pain management and tissue protection.

  19. Oleanolic acid inhibits proliferation and induces apoptosis in NB4 cells by targeting PML/RARα

    PubMed

    Li, Hongmei; He, Ning; Li, Xueyan; Zhou, Li; Zhao, Mingyu; Jiang, Hairui; Zhang, Xiaojie

    2013-10-01

    Oleanolic acid (OA), a naturally occurring pentacyclic triterpenoid contained in a variety of plant species, exhibits broad biological properties, including anticancer effects. Acute promyelocytic leukemia (APL) is a distinct subtype of acute myeloid leukemia. APL has a unique and specific chromosomal aberration, t(15;17), which results in the formation of a fusion gene and protein PML/RARα, which is not only necessary for the diagnosis of APL, but is also critical for APL pathogenesis. In the present study, the cytotoxic effect of OA on NB4 cells was investigated. Cell viability was assessed via the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The expression levels of bax and bcl-2 mRNA were determined by quantitative PCR. Apoptosis was analyzed using DNA fragment analysis and cell cycle distributions were analyzed by flow cytometry. The activity of caspase-3 and caspase-9 was determined by colorimetric assays. The expression of the PML/RARα fusion protein was analyzed by western blotting. The MTT assay showed that OA inhibited the proliferation of the NB4 cells. The expression levels of pro-apoptotic bax mRNA were increased and the levels of anti-apoptotic bcl-2 mRNA were decreased following the treatment of the NB4 cells with OA at 80 μmol/l. Treatment of the NB4 cells with OA at 80 μmol/l induced apoptosis and G1 phase arrest, while caspase-9 and caspase-3 activity was significantly increased. Furthermore, the expression of the PML/RARα fusion protein was decreased. Together, these data suggest that OA exerts a cytotoxic effect that inhibits proliferation and induces apoptosis in NB4 cells by targeting PML/RARα, making it a potent therapeutic agent against leukemia.

  20. Leucine deprivation inhibits proliferation and induces apoptosis of human breast cancer cells via fatty acid synthase

    PubMed Central

    Xiao, Fei; Wang, Chunxia; Yin, Hongkun; Yu, Junjie; Chen, Shanghai; Fang, Jing; Guo, Feifan

    2016-01-01

    Substantial studies on fatty acid synthase (FASN) have focused on its role in regulating lipid metabolism and researchers have a great interest in treating cancer with dietary manipulation of amino acids. In the current study, we found that leucine deprivation caused the FASN-dependent anticancer effect. Here we showed that leucine deprivation inhibited cell proliferation and induced apoptosis of MDA-MB-231 and MCF-7 breast cancer cells. In an in vivo tumor xenograft model, the leucine-free diet suppressed the growth of human breast cancer tumors and triggered widespread apoptosis of the cancer cells. Further study indicated that leucine deprivation decreased expression of lipogenic gene FASN in vitro and in vivo. Over-expression of FASN or supplementation of palmitic acid (the product of FASN action) blocked the effects of leucine deprivation on cell proliferation and apoptosis in vitro and in vivo. Moreover, leucine deprivation suppressed the FASN expression via regulating general control non-derepressible (GCN)2 and sterol regulatory element-binding protein 1C (SREBP1C). Taken together, our study represents proof of principle that anticancer effects can be obtained with strategies to deprive tumors of leucine via suppressing FASN expression, which provides important insights in prevention of breast cancer via metabolic intervention. PMID:27579768

  1. AR-42 induces apoptosis in human hepatocellular carcinoma cells via HDAC5 inhibition.

    PubMed

    Zhang, Mingming; Pan, Yida; Dorfman, Robert G; Chen, Zhaogui; Liu, Fuchen; Zhou, Qian; Huang, Shan; Zhang, Jun; Yang, Dongqin; Liu, Jie

    2016-04-19

    Histone deacetylases (HDACs) play critical roles in apoptosis and contribute to the proliferation of cancer cells. AR-42 is a novel Class I and II HDAC inhibitor that shows cytotoxicity against various human cancer cell lines. The present study aims to identify the target of AR-42 in hepatocellular carcinoma (HCC) as well as evaluate its therapeutic efficacy. We found that HDAC5 was upregulated in HCC tissues compared to adjacent normal tissues, and this was correlated with reduced patient survival. CCK8 and colony-formation assays showed that HDAC5 overexpression promotes proliferation in HCC cell lines. Treatment with AR-42 decreased HCC cell growth and increased caspase-dependent apoptosis, and this was rescued by HDAC5 overexpression. We demonstrated that AR-42 can inhibit the deacetylation activity of HDAC5 and its downstream targets in vitro and in vivo. Taken together, these results demonstrate for the first time that AR-42 targets HDAC5 and induces apoptosis in human hepatocellular carcinoma cells. AR-42 therefore shows potential as a new drug candidate for HCC therapy.

  2. Jolkinolide B induces apoptosis and inhibits tumor growth in mouse melanoma B16F10 cells by altering glycolysis

    PubMed Central

    Gao, Caixia; Yan, Xinyan; Wang, Bo; Yu, Lina; Han, Jichun; Li, Defang; Zheng, Qiusheng

    2016-01-01

    Most cancer cells preferentially rely on glycolysis to produce the energy (adenosine triphosphate, ATP) for growth and proliferation. Emerging evidence demonstrates that the apoptosis in cancer cells could be closely associated with the inhibition of glycolysis. In this study, we have found that jolkinolide B (JB), a bioactive diterpenoid extracted from the root of Euphorbia fischeriana Steud, induced tumor cells apoptosis and decreased the production of ATP and lactic acid in mouse melanoma B16F10 cells. Furthermore, we found that JB downregulated the mRNA expression of glucose transporter genes (Glut1, Glut3 and Glut4) and glycolysis-related kinase genes (Hk2 and Ldha) in B16F10 cells. Moreover, treatment with JB upregulated the mRNA expression of pro-apoptosis genes (Bax), downregulated the mRNA expression of anti-apoptosis genes (Bcl-2, Caspase-3 and Caspase-9), decreased the potential of mitochondrial membrane and increased reactive oxygen species (ROS) levels in B16F10 cells. Finally, intragastric administration of JB suppressed tumor growth and induced tumor apoptosis in mouse xenograft model of murine melanoma B16F10 cells. Taken together, these results suggest that JB could induce apoptosis through the mitochondrial pathway and inhibit tumor growth. The inhibition of glycolysis could play a crucial role in the induction of apoptosis in JB-treated B16F10 cells. PMID:27796318

  3. H2 and H3 relaxin inhibit high glucose-induced apoptosis in neonatal rat ventricular myocytes.

    PubMed

    Zhang, Xiaohui; Ma, Xiao; Zhao, Meng; Zhang, Bo; Chi, Jinyu; Liu, Wenxiu; Chen, Wenjia; Fu, Yu; Liu, Yue; Yin, Xinhua

    2015-01-01

    High concentrations of glucose induce cardiomyocyte apoptosis, and contribute to diabetic cardiomyopathy. Relaxin-2 and relaxin-3 are two members of the relaxin peptide family that are cardioprotective. However, it remains unknown whether relaxin-2 or relaxin-3 can regulate apoptosis in high glucose treated-neonatal rat ventricular myocytes (NRVMs). In cultured NRVMs, 33 mmol/l high glucose (HG) increased apoptosis in a time-dependent manner. HG-increased the protein expression of cleaved caspase-8 and -9, two initiators of the extrinsic and intrinsic pathways of apoptosis, Caspase-3 was attenuated by human recombinant relaxin-2 (H2 relaxin) or relaxin-3 (H3 relaxin), indicating that H2 and H3 relaxin inhibited HG-induced apoptosis. Furthermore, endoplasmic reticulum stress (ERS) markers CHOP and caspase-12 were markedly increased in HG-treated NRVMs, leading to apoptosis; this effect was also effectively attenuated by H2 relaxin or H3 relaxin. Treatment of NRVMs with HG reduced autophagy which cannot be adjusted by H2 relaxin or H3 relaxin. In conclusion, HG-induced apoptosis in NRVMs was mediated, in part, by the activation of the extrinsic and intrinsic pathways of apoptosis and ERS, all inhibited by H2 relaxin or H3 relaxin.

  4. Glycyrrhizic acid inhibits apoptosis and fibrosis in carbon-tetrachloride-induced rat liver injury

    PubMed Central

    Liang, Bo; Guo, Xiao-Ling; Jin, Jing; Ma, Yong-Chun; Feng, Zheng-Quan

    2015-01-01

    AIM: To investigate anti-apoptotic effects of glycyrrhizic acid (GA) against fibrosis in carbon tetrachloride (CCl4)-induced liver injury and its contributing factors. METHODS: Liver fibrosis was induced by administration of CCl4 for 8 wk. Pathological changes in the liver of rats were examined by hematoxylin-eosin staining. Collagen fibers were detected by Sirius red staining. Hepatocyte apoptosis was determined by TUNEL assay and the expression levels of cleaved caspase-3, Bax, α-SMA, connective tissue growth factor (CTGF), matrix metalloproteinase (MMP) 2 and MMP9 proteins were evaluated by western blot analysis, and α-SMA mRNA, collagen type I and III mRNA were estimated by real-time PCR. RESULTS: Treatment with GA significantly improved the pathological changes in the liver and markedly decreased the positive area of Sirius red compared with rats in the CCl4-treated group. TUNEL assay showed that GA significantly reduced the number of TUNEL-positive cells compared with the CCl4-treated group. The expression levels of cleaved caspase-3, Bax, α-SMA, CTGF, MMP2 and MMP9 proteins, and α-SMA mRNA, collagen type I and III mRNA were also significantly reduced by GA compared with the CCl4-treated group (P < 0.05). CONCLUSION: GA treatment can ameliorate CCl4-induced liver fibrosis by inhibiting hepatocyte apoptosis and hepatic stellate cell activation. PMID:25954100

  5. Apoptosis induced by NAD depletion is inhibited by KN-93 in a CaMKII-independent manner.

    PubMed

    Takeuchi, Mikio; Yamamoto, Tomoko

    2015-07-01

    Nicotinamide phosphoribosyltransferase (NAMPT) is a key enzyme that catalyzes the synthesis of nicotinamide mononucleotide from nicotinamide (Nam) in the salvage pathway of mammalian NAD biosynthesis. Several potent NAMPT inhibitors have been identified and used to investigate the role of intracellular NAD and to develop therapeutics. NAD depletion induced by NAMPT inhibitors depolarizes mitochondrial membrane potential and causes apoptosis in a range of cell types. However, the mechanisms behind this depolarization have not been precisely elucidated. We observed that apoptosis of THP-1 cells in response to NAMPT inhibitors was reduced by the Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) inhibitor KN-93 via an unknown mechanism. The inactive analog of KN-93, KN-92, exhibited the same activity, but the CaMKII-inhibiting cell-permeable autocamtide-2-related inhibitory peptide II did not, indicating that the inhibition of THP-1 cell apoptosis was not dependent on CaMKII. In evaluating the mechanism of action, we confirmed that KN-93 did not inhibit decreases in NAD levels but did inhibit decreases in mitochondrial membrane potential, indicating that KN-93 exerts inhibition upstream of the mitochondrial pathway of apoptosis. Further, qPCR analysis of the Bcl-2 family of proteins showed that Bim is efficiently expressed following NAMPT inhibition and that KN-92 did not inhibit this expression. The L-type Ca(2+) channel blockers verapamil and nimodipine partially inhibited apoptosis, indicating that part of this effect is dependent on Ca(2+) channel inhibition, as both KN-93 and KN-92 are reported to inhibit L-type Ca(2+) channels. On the other hand, KN-93 and KN-92 did not markedly inhibit apoptosis induced by anti-cancer agents such as etoposide, actinomycin D, ABT-737, or TW-37, indicating that the mechanism of inhibition is specific to apoptosis induced by NAD depletion. These results demonstrate that NAD depletion induces a specific type of apoptosis that

  6. Inhibition of phosphate-induced apoptosis in resting zone chondrocytes by thrombin peptide 508.

    PubMed

    Zhong, Ming; Carney, Darrell H; Ryaby, James T; Schwartz, Zvi; Boyan, Barbara D

    2009-01-01

    Growth plate chondrocytes are susceptible to apoptosis. Terminally differentiated chondrocytes are deleted via apoptosis, which primes the growth plate to vascular invasion and subsequent bone formation. Whether less differentiated resting zone chondrocytes are subject to the same mechanism that governs the apoptotic pathway of more differentiated growth zone chondrocytes is not known. In our current study, we demonstrated that inorganic phosphate, a key inducer of growth plate chondrocyte apoptosis, also causes apoptosis in resting zone chondrocytes, via a pathway similar to the one in growth zone chondrocytes. Our results demonstrated that the conditions that cause growth plate chondrocyte apoptosis lie in the external environment, instead of the differences in differentiation state.

  7. Unprecedented inhibition of tubulin polymerization directed by gold nanoparticles inducing cell cycle arrest and apoptosis

    NASA Astrophysics Data System (ADS)

    Choudhury, Diptiman; Xavier, Paulrajpillai Lourdu; Chaudhari, Kamalesh; John, Robin; Dasgupta, Anjan Kumar; Pradeep, Thalappil; Chakrabarti, Gopal

    2013-05-01

    The effect of gold nanoparticles (AuNPs) on the polymerization of tubulin has not been examined till now. We report that interaction of weakly protected AuNPs with microtubules (MTs) could cause inhibition of polymerization and aggregation in the cell free system. We estimate that single citrate capped AuNPs could cause aggregation of ~105 tubulin heterodimers. Investigation of the nature of inhibition of polymerization and aggregation by Raman and Fourier transform-infrared (FTIR) spectroscopies indicated partial conformational changes of tubulin and microtubules, thus revealing that AuNP-induced conformational change is the driving force behind the observed phenomenon. Cell culture experiments were carried out to check whether this can happen inside a cell. Dark field microscopy (DFM) combined with hyperspectral imaging (HSI) along with flow cytometric (FC) and confocal laser scanning microscopic (CLSM) analyses suggested that AuNPs entered the cell, caused aggregation of the MTs of A549 cells, leading to cell cycle arrest at the G0/G1 phase and concomitant apoptosis. Further, Western blot analysis indicated the upregulation of mitochondrial apoptosis proteins such as Bax and p53, down regulation of Bcl-2 and cleavage of poly(ADP-ribose) polymerase (PARP) confirming mitochondrial apoptosis. Western blot run after cold-depolymerization revealed an increase in the aggregated insoluble intracellular tubulin while the control and actin did not aggregate, suggesting microtubule damage induced cell cycle arrest and apoptosis. The observed polymerization inhibition and cytotoxic effects were dependent on the size and concentration of the AuNPs used and also on the incubation time. As microtubules are important cellular structures and target for anti-cancer drugs, this first observation of nanoparticles-induced protein's conformational change-based aggregation of the tubulin-MT system is of high importance, and would be useful in the understanding of cancer therapeutics

  8. Fisetin inhibits cellular proliferation and induces mitochondria-dependent apoptosis in human gastric cancer cells.

    PubMed

    Sabarwal, Akash; Agarwal, Rajesh; Singh, Rana P

    2017-02-01

    The anticancer effects of fisetin, a dietary agent, are largely unknown against human gastric cancer. Herein, we investigated the mechanisms of fisetin-induced inhibition of growth and survival of human gastric carcinoma AGS and SNU-1 cells. Fisetin (25-100 μM) caused significant decrease in the levels of G1 phase cyclins and CDKs, and increased the levels of p53 and its S15 phosphorylation in gastric cancer cells. We also observed that growth suppression and death of non-neoplastic human intestinal FHs74int cells were minimally affected by fisetin. Fisetin strongly increased apoptotic cells and showed mitochondrial membrane depolarization in gastric cancer cells. DNA damage was observed as early as 3 h after fisetin treatment which was accompanied with gamma-H2A.X(S139) phosphorylation and cleavage of PARP. Fisetin-induced apoptosis was observed to be independent of p53. DCFDA and MitoSOX analyses showed an increase in mitochondrial ROS generation in time- and dose-dependent fashion. It also increased cellular nitrite and superoxide generation. Pre-treatment with N-acetyl cysteine (NAC) inhibited ROS generation and also caused protection from fisetin-induced DNA damage. The formation of comets were observed in only fisetin treated cells which was blocked by NAC pre-treatment. Further investigation of the source of ROS, using mitochondrial respiratory chain (MRC) complex inhibitors, suggested that fisetin caused ROS generation specifically through complex I. Collectively, these results for the first time demonstrated that fisetin possesses anticancer potential through ROS production most likely via MRC complex I leading to apoptosis in human gastric carcinoma cells. © 2016 Wiley Periodicals, Inc.

  9. Sirtuin Inhibition Induces Apoptosis-like Changes in Platelets and Thrombocytopenia.

    PubMed

    Kumari, Sharda; Chaurasia, Susheel N; Nayak, Manasa K; Mallick, Ram L; Dash, Debabrata

    2015-05-08

    Sirtuins are evolutionarily conserved NAD(+)-dependent acetyl-lysine deacetylases that belong to class III type histone deacetylases. In humans, seven sirtuin isoforms (Sirt1 to Sirt7) have been identified. Sirtinol, a cell-permeable lactone ring derived from naphthol, is a dual Sirt1/Sirt2 inhibitor of low potency, whereas EX-527 is a potent and selective Sirt1 inhibitor. Here we demonstrate that Sirt1, Sirt2, and Sirt3 are expressed in enucleate platelets. Both sirtinol and EX-527 induced apoptosis-like changes in platelets, as revealed by enhanced annexin V binding, reactive oxygen species production, and drop in mitochondrial transmembrane potential. These changes were associated with increased phagocytic clearance of the platelets by macrophages. Expression of acetylated p53 and the conformationally active form of Bax were found to be significantly higher in both sirtinol- and EX-527-treated platelets, implicating the p53-Bax axis in apoptosis induced by sirtuin inhibitors. Administration of either sirtinol or EX-527 in mice led to a reduction in both platelet count and the number of reticulated platelets. Our results, for the first time, implicate sirtuins as a central player in the determination of platelet aging. Because sirtuin inhibitors are being evaluated for their antitumor activity, this study refocuses attention on the potential side effect of sirtuin inhibition in delimiting platelet life span and management of thrombosis.

  10. The flavonoid component isorhamnetin in vitro inhibits proliferation and induces apoptosis in Eca-109 cells.

    PubMed

    Ma, Gang; Yang, Chunlei; Qu, Yi; Wei, Huaying; Zhang, Tongtong; Zhang, Najuan

    2007-04-25

    Isorhamnetin is one member of flavonoid components which has been used in the treatment of heart disease. Recently the in vitro anti-cancer effect of isorhamnetin on human esophageal squamous carcinoma cell line Eca-109 was investigated in our lab. When Eca-109 cells were in vitro exposed to the graded doses of isorhamnetin (0-80 microg/ml) for 48 h, respectively, isorhamnetin exhibited cytostatic effect on the treated cells, with an IC(50) of 40+/-0.08 microg/ml as estimated by MTT assay. Inhibition on proliferation by isorhamnetin was detected by trypan blue exclusion assay, clone formation test, immunocytochemical assay of PCNA and (3)H-thymidine uptake analysis. Cell cycle distribution was measured by FCM. It was found that the viability of Eca-109 cells was significantly hampered by isorhamnetin. Compared with the negative control group, the treated group which was exposed to isorhamnetin had increased population in G(0)/G(1) phase from 74.6 to 84 while had a significant reduction in G(2)/M phase from 11.9 to 5.8. In addition to its cytostatic effect, isorhamnetin also showed stimulatory effect on apoptosis. Typical apoptotic morphology such as condensation and fragmentation of nuclei and blebbing membrane of the apoptotic cells could be observed through transmission electron microscope. Moreover, the sharp increase in apoptosis rate between the control and treated group were detected by FCM from 6.3 to 16.3. To explore the possible molecular mechanisms that underlie the growth inhibition and apoptosis stimulatory effects of isorhamnetin, the expressions of six proliferation- and death-related genes were detected by FCM. Expressions of bcl-2, c-myc and H-ras were downregulated whereas Bax, c-fos and p53 were upregulated. However, the in vivo experiments were required to further confirm the anti-cancer effects of isorhamnetin. In conclusion, isorhamnetin appears to be a potent drug against esophageal cancer due to its in vitro potential to not only inhibit

  11. Autophagy and gap junctional intercellular communication inhibition are involved in cadmium-induced apoptosis in rat liver cells

    SciTech Connect

    Zou, Hui; Zhuo, Liling; Han, Tao; Hu, Di; Yang, Xiaokang; Wang, Yi; Yuan, Yan; Gu, Jianhong; Bian, Jianchun; Liu, Xuezhong; Liu, Zongping

    2015-04-17

    Cadmium (Cd) is known to induce hepatotoxicity, yet the underlying mechanism of how this occurs is not fully understood. In this study, Cd-induced apoptosis was demonstrated in rat liver cells (BRL 3A) with apoptotic nuclear morphological changes and a decrease in cell index (CI) in a time- and concentration-dependent manner. The role of gap junctional intercellular communication (GJIC) and autophagy in Cd-induced apoptosis was investigated. Cd significantly induced GJIC inhibition as well as downregulation of connexin 43 (Cx43). The prototypical gap junction blocker carbenoxolone disodium (CBX) exacerbated the Cd-induced decrease in CI. Cd treatment was also found to cause autophagy, with an increase in mRNA expression of autophagy-related genes Atg-5, Atg-7, Beclin-1, and microtubule-associated protein light chain 3 (LC3) conversion from cytosolic LC3-I to membrane-bound LC3-II. The autophagic inducer rapamycin (RAP) prevented the Cd-induced CI decrease, while the autophagic inhibitor chloroquine (CQ) caused a further reduction in CI. In addition, CBX promoted Cd-induced autophagy, as well as changes in expression of Atg-5, Atg-7, Beclin-1 and LC3. CQ was found to block the Cd-induced decrease in Cx43 and GJIC inhibition, whereas RAP had opposite effect. These results demonstrate that autophagy plays a protective role during Cd-induced apoptosis in BRL 3A cells during 6 h of experiment, while autophagy exacerbates Cd-induced GJIC inhibition which has a negative effect on cellular fate. - Highlights: • GJIC and autophagy is crucial for biological processes. • Cd exposure causes GJIC inhibition and autophagy increase in BRL 3A cells. • Autophagy protects Cd induced BRL 3A cells apoptosis at an early stage. • Autophagy exacerbates Cd-induced GJIC inhibition. • GJIC plays an important role in autophagy induced cell death or survival.

  12. Belinostat-induced apoptosis and growth inhibition in pancreatic cancer cells involve activation of TAK1-AMPK signaling axis

    SciTech Connect

    Wang, Bing Wang, Xin-bao; Chen, Li-yu; Huang, Ling; Dong, Rui-zen

    2013-07-19

    Highlights: •Belinostat activates AMPK in cultured pancreatic cancer cells. •Activation of AMPK is important for belinostat-induced cytotoxic effects. •ROS and TAK1 are involved in belinostat-induced AMPK activation. •AMPK activation mediates mTOR inhibition by belinostat. -- Abstract: Pancreatic cancer accounts for more than 250,000 deaths worldwide each year. Recent studies have shown that belinostat, a novel pan histone deacetylases inhibitor (HDACi) induces apoptosis and growth inhibition in pancreatic cancer cells. However, the underlying mechanisms are not fully understood. In the current study, we found that AMP-activated protein kinase (AMPK) activation was required for belinostat-induced apoptosis and anti-proliferation in PANC-1 pancreatic cancer cells. A significant AMPK activation was induced by belinostat in PANC-1 cells. Inhibition of AMPK by RNAi knockdown or dominant negative (DN) mutation significantly inhibited belinostat-induced apoptosis in PANC-1 cells. Reversely, AMPK activator AICAR and A-769662 exerted strong cytotoxicity in PANC-1 cells. Belinostat promoted reactive oxygen species (ROS) production in PANC-1 cells, increased ROS induced transforming growth factor-β-activating kinase 1 (TAK1)/AMPK association to activate AMPK. Meanwhile, anti-oxidants N-Acetyl-Cysteine (NAC) and MnTBAP as well as TAK1 shRNA knockdown suppressed belinostat-induced AMPK activation and PANC-1 cell apoptosis. In conclusion, we propose that belinostat-induced apoptosis and growth inhibition require the activation of ROS-TAK1-AMPK signaling axis in cultured pancreatic cancer cells.

  13. Preventive effects of imperatorin on perfluorohexanesulfonate-induced neuronal apoptosis via inhibition of intracellular calcium-mediated ERK pathway

    PubMed Central

    Lee, Eunkyung; Choi, So-Young; Yang, Jae-Ho

    2016-01-01

    Early life neuronal exposure to environmental toxicants has been suggested to be an important etiology of neurodegenerative disease development. Perfluorohexanesulfonate (PFHxS), one of the major perfluoroalkyl compounds, is widely distributed environmental contaminants. We have reported that PFHxS induces neuronal apoptosis via ERK-mediated pathway. Imperatorin is a furanocoumarin found in various edible plants and has a wide range of pharmacological effects including neuroprotection. In this study, the effects of imperatorin on PFHxS-induced neuronal apoptosis and the underlying mechanisms are examined using cerebellar granule cells (CGC). CGC were isolated from seven-day old rats and were grown in culture for seven days. Caspase-3 activity and TUNEL staining were used to determine neuronal apoptosis. PFHxS-induced apoptosis of CGC was significantly reduced by imperatorin and PD98059, an ERK pathway inhibitor. PFHxS induced a persistent increase in intracellular calcium, which was significantly blocked by imperatorin, NMDA receptor antagonist, MK801 and the L-type voltage-dependent calcium channel blockers, diltiazem and nifedipine. The activation of caspase-3 by PFHxS was also inhibited by MK801, diltiazem and nifedipine. PFHxS-increased ERK activation was inhibited by imperatorin, MK801, diltiazem and nifedipine. Taken together, imperatorin protects CGC against PFHxS-induced apoptosis via inhibition of NMDA receptor/intracellular calcium-mediated ERK pathway. PMID:27382356

  14. Galangin inhibits cell invasion by suppressing the epithelial-mesenchymal transition and inducing apoptosis in renal cell carcinoma.

    PubMed

    Cao, Jingyi; Wang, Hainan; Chen, Feifei; Fang, Jianzheng; Xu, Aiming; Xi, Wei; Zhang, Shengli; Wu, Gang; Wang, Zengjun

    2016-05-01

    Galangin, a flavonoid extracted from the root of the Alpinia officinarum Hence, has been shown to have anticancer properties against several types of cancer cells. However, the influence of galangin on human renal cancer cells remains to be elucidated. In the present study, proliferation of 786‑0 and Caki‑1 cells was suppressed following exposure to various doses of galangin. Cell invasion and wound healing assays were used to observe the effect of galangin on invasion and migration. The results demonstrated that Galangin inhibited cell invasion by suppressing the epithelial mesenchymal transition (EMT), with an increase in the expression of E‑cadherin and decreased expression levels of N‑cadherin and vimentin. The apoptosis induced by galangin was analyzed by flow cytometry. The results revealed that galangin induced apoptosis in a dose‑dependent manner. The accumulation of reactive oxygen species (ROS) is an important contributing factor for the apoptosis of various types of cancer cell. The dichlorofluorescein-diacetate method was used to determine the level of ROS. Galangin induced the accumulation of intracellular ROS and malondialdehyde, and decreased the activities of total antioxidant and superoxide dismutase in renal cell carcinoma cells. Galangin exerted an antiproliferative effect and inhibited renal cell carcinoma invasion by suppressing the EMT. This treatment also induced apoptosis, accompanied by the production of ROS. Therefore, the present data suggested that galangin may have beneficial effects by preventing renal cell carcinoma growth, inhibiting cell invasion via the EMT and inducing cell apoptosis.

  15. Galangin inhibits cell invasion by suppressing the epithelial-mesenchymal transition and inducing apoptosis in renal cell carcinoma

    PubMed Central

    CAO, JINGYI; WANG, HAINAN; CHEN, FEIFEI; FANG, JIANZHENG; XU, AIMING; XI, WEI; ZHANG, SHENGLI; WU, GANG; WANG, ZENGJUN

    2016-01-01

    Galangin, a flavonoid extracted from the root of the Alpinia officinarum Hence, has been shown to have anticancer properties against several types of cancer cells. However, the influence of galangin on human renal cancer cells remains to be elucidated. In the present study, proliferation of 786-0 and Caki-1 cells was suppressed following exposure to various doses of galangin. Cell invasion and wound healing assays were used to observe the effect of galangin on invasion and migration. The results demonstrated that Galangin inhibited cell invasion by suppressing the epithelial mesenchymal transition (EMT), with an increase in the expression of E-cadherin and decreased expression levels of N-cadherin and vimentin. The apoptosis induced by galangin was analyzed by flow cytometry. The results revealed that galangin induced apoptosis in a dose-dependent manner. The accumulation of reactive oxygen species (ROS) is an important contributing factor for the apoptosis of various types of cancer cell. The dichlorofluorescein-diacetate method was used to determine the level of ROS. Galangin induced the accumulation of intracellular ROS and malondialdehyde, and decreased the activities of total antioxidant and superoxide dismutase in renal cell carcinoma cells. Galangin exerted an antiproliferative effect and inhibited renal cell carcinoma invasion by suppressing the EMT. This treatment also induced apoptosis, accompanied by the production of ROS. Therefore, the present data suggested that galangin may have beneficial effects by preventing renal cell carcinoma growth, inhibiting cell invasion via the EMT and inducing cell apoptosis. PMID:27035542

  16. Anticancer effect of xanthohumol induces growth inhibition and apoptosis of human liver cancer through NF-κB/p53-apoptosis signaling pathway.

    PubMed

    Zhao, Xiangqian; Jiang, Kai; Liang, Bin; Huang, Xiaoqiang

    2016-02-01

    Xanthohumol may prevent and cure diabetes and atherosis, have oxidation resistance and antiviral function as well as anticancer effect preventing cancer cell metastasis. We investigate whether the anticancer effect of xanthohumol induces growth inhibition and apoptosis of human liver cancer through NF-κB/p53-apoptosis signaling pathway. Human liver cancer HepG2 cell were treated with 10, 20, 30 and 40 µM xanthohumol for 48 h. The present study showed that the anticancer effect of xanthohumol was effective in inhibiting proliferation and inducing apoptosis of human liver cancer HepG2 cells. Furthermore, the caspase-3 activity of human liver cancer HepG2 cells was increased by xanthohumol. In addition, 48-h treatment with xanthohumol suppressed NF-κB expression and promoted p53, cleaved PARP, AIF and cytochrome c expression and downregulated XIAP and Bcl-2/Bax expression in human liver cancer HepG2 cells. Therefore, the anticancer effect of xanthohumol induces growth inhibition and apoptosis of human liver cancer through the NF-κB/p53-apoptosis signaling pathway.

  17. Anticancer effect of xanthohumol induces growth inhibition and apoptosis of human liver cancer through NF-κB/p53-apoptosis signaling pathway

    PubMed Central

    ZHAO, XIANGQIAN; JIANG, KAI; LIANG, BIN; HUANG, XIAOQIANG

    2016-01-01

    Xanthohumol may prevent and cure diabetes and atherosis, have oxidation resistance and antiviral function as well as anticancer effect preventing cancer cell metastasis. We investigate whether the anticancer effect of xanthohumol induces growth inhibition and apoptosis of human liver cancer through NF-κB/p53-apoptosis signaling pathway. Human liver cancer HepG2 cell were treated with 10, 20, 30 and 40 µM xanthohumol for 48 h. The present study showed that the anticancer effect of xanthohumol was effective in inhibiting proliferation and inducing apoptosis of human liver cancer HepG2 cells. Furthermore, the caspase-3 activity of human liver cancer HepG2 cells was increased by xanthohumol. In addition, 48-h treatment with xanthohumol suppressed NF-κB expression and promoted p53, cleaved PARP, AIF and cytochrome c expression and downregulated XIAP and Bcl-2/Bax expression in human liver cancer HepG2 cells. Therefore, the anticancer effect of xanthohumol induces growth inhibition and apoptosis of human liver cancer through the NF-κB/p53-apoptosis signaling pathway. PMID:26718026

  18. PEDF inhibits AGE-induced podocyte apoptosis via PPAR-gamma activation.

    PubMed

    Ishibashi, Yuji; Matsui, Takanori; Ohta, Keisuke; Tanoue, Ryuichiro; Takeuchi, Masayoshi; Asanuma, Katsuhiko; Fukami, Kei; Okuda, Seiya; Nakamura, Kei-ichiro; Yamagishi, Sho-ichi

    2013-01-01

    Advanced glycation end products (AGEs) formed at an accelerated rate under diabetes, elicit oxidative and pro-apoptotic reactions in various types of cells, including podocytes, thus being involved in the development and progression of diabetic nephropathy. Recently, we, along with others, have found that pigment epithelium-derived factor (PEDF), a glycoprotein with potent neuronal differentiating activity, inhibits AGE-elicited mesangial and tubular cell damage through its anti-oxidative properties. However, the effects of PEDF on podocyte loss, one of the characteristic features of diabetic nephropathy remain unknown. In this study, we investigated whether and how PEDF could protect against AGE-elicited podocyte apoptosis in vitro. AGEs decreased PEDF mRNA level in podocytes, which was blocked by neutralizing antibody raised against receptor for AGEs (RAGE-Ab). PEDF or RAGE-Ab was found to inhibit the AGE-induced up-regulation of RAGE mRNA level, oxidative stress generation and resultant apoptosis in podocytes. All of the beneficial effects of PEDF on AGE-exposed podocytes were blocked by the treatment of GW9662, an inhibitor of peroxisome proliferator-activated receptor-γ (PPARγ). Further, although PEDF did not affect protein expression levels of PPARγ, it significantly restored the PPARγ transcriptional activity in AGE-exposed podocytes. The present results demonstrated for the first time that PEDF could block the AGE-induced apoptotic cell death of podocytes by suppressing RAGE expression and subsequent ROS generation partly via PPARγ activation. Our present study suggests that substitution of PEDF proteins may be a promising strategy for preventing the podocyte loss in diabetic nephropathy.

  19. Knockdown of GPR137 by RNAi inhibits pancreatic cancer cell growth and induces apoptosis.

    PubMed

    Cui, Xianping; Liu, Yanguo; Wang, Bo; Xian, Guozhe; Liu, Xin; Tian, Xingsong; Qin, Chengkun

    2015-01-01

    G-protein-coupled receptors (GPCRs), the largest family of cell-surface molecules involved in a number of biological and pathological processes, have recently emerged as key players in carcinogenesis and cancer progression. Orphan G protein-coupled receptors (oGPCRs) are a group of proteins lacking endogenous ligands. GPR137, one of the novel oGPCR genes, was discovered by homology screening. However, the biological role of GPR137 in cancers has not yet been discussed and is of great therapeutic interest. In this study, we knocked down GPR137 via a lentivirus system in two human pancreatic cancer cell lines BXPC-3 and PANC-1. Knockdown of GPR137 strongly inhibited cell proliferation and colony formation. Flow cytometry showed that cell cycle was arrested in the sub-G1 phase and apoptotic cells were significantly increased after GPR137 knockdown. Western blotting confirmed that GPR137 silencing induced apoptosis due to cleavage of PARP (poly ADP-ribose polymerase) and upregulation of caspase 3. Furthermore, lentivirus-mediated overexpression of GPR137 promoted the proliferation of PANC-1 cells, suggesting GPR137 as a potential oncogene in pancreatic cancer cells. Taken together, our results prove the importance of GPR137 as a crucial regulator in controlling cancer cell growth and apoptosis.

  20. Kuntai Capsule Inhibited Endometriosis via Inducing Apoptosis in a Rat Model

    PubMed Central

    Ma, Aying; Zhu, Jianping; Li, Guoting; Xie, Shuwu; Li, Zhao; Gui, Youlun

    2016-01-01

    We evaluated the effectiveness of Kuntai Capsule (KTC) for treating endometriosis using rat model and investigated its preliminary mechanism of action involved. SD rats were implanted with endometrial tissues and treated with KTC for three weeks. Then, laparotomy was performed to examine volume changes of the autografts. The serum levels of TNF-α, IL-6, COX-2, E2, and P4 were measured through ELISA. TUNEL was performed to analyze the apoptosis on ectopic endometrium. Protein levels of caspases 8, 9, and 3 and cytochrome c in the ectopic and eutopic endometrium were measured by western blotting. Results showed that KTC significantly decreased the volumes of ectopic endometrium. The level of TNF-α increased and E2 decreased in the KTC treatment groups. TUNEL and western blot assay showed that KTC could induce apoptosis of endometriotic tissues, accompanied with the increased protein expression of caspases 8 and 9, activated caspase-3, and cytochrome c in a dose-dependent manner. However, these protein expression profiles were not affected in eutopic endometrium. Our findings suggest that KTC could inhibit the growth of ectopic endometrial tissue through upregulating the level of TNF-α and its downstream signaling, including caspases and cytochrome c. PMID:27597876

  1. Devazepide, a nonpeptide antagonist of CCK receptors, induces apoptosis and inhibits Ewing tumor growth.

    PubMed

    Carrillo, Jaime; Agra, Noelia; Fernández, Noemí; Pestaña, Angel; Alonso, Javier

    2009-08-01

    The Ewing family of tumors is a group of highly malignant tumors that mainly arise in bone and most often affect children and young adults in the first two decades of life. Despite the use of multimodal therapy, the long-term disease-free survival rate of patients with Ewing tumors is still disappointingly low, making the discovery of innovative therapeutic strategies all the more necessary. We have recently shown that cholecystokinin (CCK), a neuroendocrine peptide, involved in many biological functions, including cell growth and proliferation, is a relevant target of the EWS/FLI1 oncoprotein characteristic of Ewing tumors. CCK silencing inhibits cell proliferation and tumor growth in vivo, suggesting that CCK acts as an autocrine growth factor for Ewing cells. Here, we analyzed the impact of two CCK receptor antagonists, devazepide (a CCK1-R antagonist) and L365 260 (a CCK2-R antagonist), on the growth of Ewing tumor cells. Devazepide (10 micromol/l) inhibited cell growth of four different Ewing tumor cells in vitro (range 85-88%), whereas the effect of the CCK2-R antagonist on cell growth was negligible. In a mouse tumor xenograft model, devazepide reduced tumor growth by 40%. Flow cytometry experiments showed that devazepide, but not L365 260, induced apoptosis of Ewing tumor cells. In summary, devazepide induces cell death of Ewing tumor cells, suggesting that it could represent a new therapeutic approach in the management of Ewing's tumor patients.

  2. [Cold inducible RNA-binding protein inhibits hippocampal neuronal apoptosis under hypothermia by regulating redox system].

    PubMed

    Li, Jing-Hui; Zhang, Xue; Meng, Yu; Li, Chang-Sheng; Ji, Hong; Yang, Huan-Min; Li, Shi-Ze

    2015-08-25

    In this study, we intend to confirm our hypothesis that cold inducible RNA-binding protein (CIRP) can inhibit neuronal apoptosis through suppressing the formation of oxygen free radicals under hypothermia. Primary rat hippocampal neurons were isolated and cultured in vitro, and were divided into five groups: (1) normal control group (37 °C), (2) cells infected by empty viral vector group, (3) CIRP over-expressed group, (4) CIRP knock-down group, and (5) hypothermia control group. Cells in groups 2-5 were cultured under 32 °C, 5% CO2. Apoptosis of hippocampal neurons were detected by Annexin V-FITC/PI staining and flow cytometry; Expression of CIRP was determined by Western blot; Redox-related parameters (T-AOC, GSH-Px, SOD, MDA) were detected by ELISA kits. Results showed that CIRP expression levels were significantly increased (P < 0.01) and the apoptotic rates were significantly decreased (P < 0.01) in hypothermia control group and CIRP over-expressed group when compared with normal control group. On the other hand, the apoptotic rate was significantly increased (P < 0.05) in CIRP knock-down group compared with that in hypothermia control group. The levels of redox parameters in hypothermia control group and CIRP over-expressed group were significantly changed in comparison with those in normal control group, CIRP knock-down group and empty viral vector infected group, respectively (P < 0.05 or P < 0.01). These results suggest that up-regulation of CIRP by hypothermia treatment can protect the neuron from apoptosis through suppressing the formation of oxygen free radicals.

  3. Levofolene modulates apoptosis induced by 5-fluorouracil through autophagy inhibition: clinical and occupational implications.

    PubMed

    Lamberti, Monica; Porto, Stefania; Zappavigna, Silvia; Stiuso, Paola; Tirino, Virginia; Desiderio, Vincenzo; Mele, Luigi; Caraglia, Michele

    2015-05-01

    5-Fluorouracil (5-FU), often used in combination with levofolene (LF), can induce, as an important side effect, the hand-foot syndrome (HFS) due to toxicity on keratinocytes. This can also damage workers involved in its handling. In the present study, we investigated the mechanisms of the toxicity induced by 5-FU alone or together with LF on human keratinocytes in culture. We found that the two drugs, as expected, had potentiating activity on keratinocyte growth inhibition and that this effect was mediated by induction of apoptosis. In our experimental model, an increased autophagic vacuole accumulation was observed in keratinocytes treated with 5-FU as a significant increase of the monodansylcadaverine (MDC) labeling (marker of late autophagy vacuoles) was recorded. However, the synergism of 5-FU with LF on apoptotic occurrence was not paralleled by a similar increase in autophagic vacuoles at 72 h suggesting an antagonistic effect of LF on autophagy elicited by 5-FU. Differential effects on reactive oxygen species (ROS) elevation in cells treated with 5-FU alone or the combination between 5-FU and LF were also observed. 5-FU induced a time-dependent increase of both O2- and lipid peroxidation while the combination of 5-FU and LF caused a stronger intracellular O2- increase only at 24 h while at 48 and 72 h its effect was lower when compared with that one of 5-FU alone. On the other hand, the addition of LF to 5-FU caused a stronger increase of lipid peroxidation at 48 and 72 h, but its effects were significantly lower at 24 h. These results suggest for the first time that LF potentiates the cytotoxicity of 5-FU on keratinocytes likely through the antagonism on autophagy escape pathway and consequent apoptosis potentiation.

  4. Activation of PPARγ suppresses proliferation and induces apoptosis of esophageal cancer cells by inhibiting TLR4-dependent MAPK pathway.

    PubMed

    Wu, Kai; Yang, Yang; Liu, Donglei; Qi, Yu; Zhang, Chunyang; Zhao, Jia; Zhao, Song

    2016-07-12

    Although substantial studies on peroxisome proliferator-activated receptor g (PPARg) have focused on the mechanisms by which PPARg regulates glucose and lipid metabolism, recent reports have suggested that PPARg shows tumorigenic or antitumorigenic effects. The roles and mechanisms of PPARg activation in esophageal cancer remain unclarified. EC109 and TE10 esophageal cancer cells were treated with 0, 10, 20 and 40 mM of PPARg agonist rosiglitazone (RGZ) for 24, 48, and 72 h, and the cell viability and apoptosis were detected using methyl thiazolyl tetrazolium (MTT) assay and Flow cytometric (FCM) analysis, respectively. Moreover, the effects of inhibition of PPARg by antagonist or specific RNA interference on cell viability, apoptosis, the Toll-like receptor 4 (TLR4) and mitogen-activated protein kinase (MAPK) pathways were evaluated. Additionally, the effect of TLR4 signaling on the MAPK pathway, cell viability and apoptosis was assessed. The results showed that RGZ suppressed proliferation and induced apoptosis of esophageal cancer cells, which could be partly restored by inactivation of PPARg. RGZ suppressed the MAPK and TLR4 pathways, and the inhibitory effect could be counteracted by PPARg antagonist or specific RNA interference. We also suggested that MAPK activation was regulated by the TLR4 pathway and that blocking the TLR4 and MAPK pathways significantly suppressed proliferation and induced apoptosis of esophageal cancer cells. In conclusion, our data suggested that activation of PPARg suppressed proliferation and induced apoptosis of esophageal cancer cells by inhibiting TLR4-dependent MAPK pathway.

  5. Luteolin inhibited proliferation and induced apoptosis of prostate cancer cells through miR-301

    PubMed Central

    Han, Kun; Meng, Wei; Zhang, Jian-jun; Zhou, Yan; Wang, Ya-ling; Su, Yang; Lin, Shu-chen; Gan, Zhi-hua; Sun, Yong-ning; Min, Da-liu

    2016-01-01

    Luteolin is a falvonoid compound derived from Lonicera japonica Thunb. Numerous reports have demonstrated that luteolin has anticancer effects on many kinds of tumors. This study investigated the effects of luteolin on prostate cancer (PCa), assessing the PC3 and LNCaP cells. The cell viability and apoptosis were assessed by performing Cell Counting Kit-8 assay and Annexin V–fluorescein isothiocyanate/propidium iodide double staining. Luteolin was found to inhibit androgen-sensitive and androgen-independent PCa cell lines’ growth and induced apoptosis. To uncover the exact mechanisms and molecular targets, microRNA (miR) array analysis was performed. miR-301 was found to be markedly downregulated. Then, the expression of miR-301 was retrospectively analyzed in the primary PCa tissues by quantitative reverse transcription polymerase chain reaction and in situ hybridization methods. According to the quantitative reverse transcription polymerase chain reaction results of miR-301, the 54 PCa patients were divided into two groups: high and low miR-301 groups. The division indicator is a relative expression ≥5. Compared to the low-expression group, high miR-301 expression was associated with a significantly shorter overall survival (P=0.029). The proapoptotic gene, DEDD2, was predicted to be the direct target of miR-301. It was clarified in accordance with bioinformatics and luciferase activity analyses. The overexpression of miR-301 by plasmid decreased the luteolin effect. Taken together, these results suggest that luteolin inhibits PCa cell proliferation through miR-301, the poor predictive factor of PCa. PMID:27307749

  6. Neovibsanin B inhibits human malignant brain tumor cell line proliferation and induces apoptosis.

    PubMed

    Cui, Yi-Fen; Yuan, Xiao-Lin; Fan, Wen-Hai; Li, Sheng-Fan; Deng, Yu-Qin; Zhang, Qing; Zhang, Chun-Lei; Yang, Zhen

    2015-01-01

    The present study was designed to examine the effect of neovibsanin B on glioma cell viability, apoptosis and on the survival time in mice bearing tumor xenografts. The results demonstrated that neovibsanin B significantly reduced the cell viability of GL261-NS and GL261-AC cells in a dose-dependent manner. However the inhibition of proliferation was more significant in GL261-NS cells. The IC50 value of neovibsanin B against GL261-NS and GL261-AC cells is 5 and 25 nM, respectively. The inhibitory effect of neovibsanin B on cell growth was more effective than that of vincristine (VCR) (P < 0.05). We also observed a significant decrease in sphere-forming ability of GL261-NS cells on treatment with neovibsanin B. The number of colonies formed by GL261-NS cells on treatment with neovibsanin B, VCR and DMSO were 3.34 ± 1.02, 12.53 ± 3.46 and 61.34 ± 9.89% respectively after 7 days. The flow cytometry revealed a marked increase in apoptotic cell death of GL261-NS cells on treatment with neovibsanin B. The western blots showed a significant decrease in the level of activated caspase-3 on treatment with neovibsanin B after 24 h. In addition, neovibsanin B increased the median survival time of glioma-bearing mice (P < 0.05). Therefore, neovibsanin B effectively inhibits glioma cell viability by inducing apoptosis, and can be a potent therapeutic agent for the treatment of malignant glioma.

  7. RUNX3 inhibits survivin expression and induces cell apoptosis in gastric cancer.

    PubMed

    Liu, Zhifang; Zhang, Xinchao; Xu, Xia; Chen, Long; Li, Wenjuan; Yu, Han; Sun, Yundong; Zeng, Jiping; Jia, Jihui

    2014-03-01

    Transcription factor RUNX3 is associated with gastric tumorigenesis and progression through regulating the expression of its target genes. Survivin is a member of the inhibitor of apoptosis (IAP) family and has been shown to inhibit cell apoptosis and promote cell proliferation. Increased survivin expression has been found in various cancer types, including gastric cancer. In this study, we found that restoration of RUNX3 promotes cell apoptosis through inhibiting the survivin expression, while RUNX3 inhibition increases the expression of survivin in gastric cancer cell lines. Moreover, RUNX3 over-expression inhibits,whereas its inhibition increases, the promoter activity of survivin gene, respectively. RUNX3-R122C, a mutation located in the conserved Runt domain, has no effect on the promoter activity of survivin gene. We further identified a RUNX3-binding site in the promoter of survivin gene and the binding of RUNX3 on survivin promoter leads to significantly inhibition of survivin expression. Finally, we confirmed the negative correlation of RUNX3 and survivin expression in clinical specimens of gastric cancer. These findings reveal a novel mechanism of RUNX3 for the induction of cell apoptosis in human gastric cancer.

  8. Inhibition of aldehyde dehydrogenase 2 activity enhances antimycin-induced rat cardiomyocytes apoptosis through activation of MAPK signaling pathway.

    PubMed

    Zhang, Peng; Xu, Danling; Wang, Shijun; Fu, Han; Wang, Keqiang; Zou, Yunzeng; Sun, Aijun; Ge, Junbo

    2011-12-01

    Aldehyde dehydrogenase 2 (ALDH2), a mitochondrial-specific enzyme, has been proved to be involved in oxidative stress-induced cell apoptosis, while little is known in cardiomyocytes. This study was aimed at investigating the role of ALDH2 in antimycin A-induced cardiomyocytes apoptosis by suppressing ALDH2 activity with a specific ALDH2 inhibitor Daidzin. Antimycin A (40μg/ml) was used to induce neonatal cardiomyocytes apoptosis. Daidzin (60μM) effectively inhibited ALDH2 activity by 50% without own effect on cell apoptosis, and significantly enhanced antimycin A-induced cardiomyocytes apoptosis from 33.5±4.4 to 56.5±6.4% (Hochest method, p<0.05), and from 57.9±1.9 to 74.0±11.9% (FACS, p<0.05). Phosphorylation of activated MAPK signaling pathway, including extracellular signal-regulated kinase (ERK1/2), c-Jun NH2-terminal kinase (JNK) and p38 was also increased in antimycin A and daidzin treated cardiomyocytes compared to the cells treated with antimycin A alone. These findings indicated that modifying mitochondrial ALDH2 activity/expression might be a potential therapeutic option on reducing oxidative insults induced cardiomyocytes apoptosis.

  9. Taurine inhibits 2,5-hexanedione-induced oxidative stress and mitochondria-dependent apoptosis in PC12 cells

    PubMed Central

    LI, Shuangyue; GUAN, Huai; QIAN, Zhiqiang; SUN, Yijie; GAO, Chenxue; LI, Guixin; YANG, Yi; PIAO, Fengyuan; HU, Shuhai

    2016-01-01

    2,5-hexanedione (HD) is the ultimate neurotoxic metabolite of hexane, causing the progression of nerve diseases in human. It was reported that HD induced apoptosis and oxidative stress. Taurine has been shown to be a potent antioxidant. In the present study, we investigated the protection of taurine against HD-induced apoptosis in PC12 cells and the underlying mechanism. Our results showed the decreased viability and increased apoptosis in HD-exposed PC12 cells. HD also induced the disturbance of Bax and Bcl-2 expression, the loss of MMP, the release of mitochondrial cytochrome c and caspase-3 activation in PC12 cells. Moreover, HD resulted in an increase in reactive oxygen species (ROS) level and a decline in the activities of superoxidedismutase and catalase in PC12 cells. However, taurine pretreatment ameliorated the increased apoptosis and the alterations in key regulators of mitochondria-dependent pathway in PC12 exposed to HD. The increased ROS level and the decreased activities of the antioxidant enzymes in HD group were attenuated by taurine. These results indicate that pretreatment of taurine may, at least partly, prevent HD-induced apoptosis via inhibiting mitochondria-dependent pathway. It is also suggested that the potential of taurine against HD-induced apoptosis may benefit from its anti-oxidative property. PMID:27840369

  10. 3-Bromopyruvate and sodium citrate induce apoptosis in human gastric cancer cell line MGC-803 by inhibiting glycolysis and promoting mitochondria-regulated apoptosis pathway.

    PubMed

    Guo, Xingyu; Zhang, Xiaodong; Wang, Tingan; Xian, Shulin; Lu, Yunfei

    2016-06-17

    Cancer cells are mainly dependent on glycolysis to generate adenosine triphosphate (ATP) and intermediates required for cell growth and proliferation. Thus, inhibition of glycolysis might be of therapeutic value in antitumor treatment. Our previously studies had found that both 3-bromopyruvate (BP) and sodium citrate (SCT) can inhibit tumor growth and proliferation in vitro and in vivo. However, the mechanism involved in the BP and SCT mediated antitumor activity is not entirely clear. In this work, it is demonstrated that BP inhibits the enzyme hexokinase (HK) activity and SCT suppresses the phosphofructokinase (PFK) activity respectively, both the two agents decrease viability, ATP generation and lactate content in the human gastric cancer cell line MGC-803. These effects are directly correlated with blockage of glycolysis. Furthermore, BP and SCT can induce the characteristic manifestations of mitochondria-regulated apoptosis, such as down-regulation of anti-apoptosis proteins Bcl-2 and Survivin, up-regulation of pro-apoptosis protein Bax, activation of caspase-3, as well as leakage of cytochrome c (Cyt-c). In summary, our results provided evidences that BP and SCT inhibit the MGC-803 cells growth and proliferation might be correlated with inhibiting glycolysis and promoting mitochondria-regulated apoptosis.

  11. Didymin Induces Apoptosis by Inhibiting N-Myc and up regulating RKIP in Neuroblastoma

    PubMed Central

    Singhal, Jyotsana; Nagaprashantha, Lokesh Dalasanur; Vatsyayan, Rit; Singhal, Ashutosh; Awasthi, Sanjay; Singhal, Sharad S

    2011-01-01

    Neuroblastomas arise from the neural crest cells and represent the most common solid tumors outside the nervous system in children. The amplification of N-Myc plays a primary role in the pathogenesis of neuroblastomas whereas acquired mutations of p53 lead to refractory and relapsed cases of neuroblastomas. In this regard, dietary compounds which can target N-Myc and exert anti-cancer effects independent of p53 status acquire significance in the management of neuroblastomas. Hence, we investigated the anti-cancer properties of the flavonoid didymin in neuroblastomas. Didymin effectively inhibited proliferation and induced apoptosis irrespective of p53 status in neuroblastomas. Didymin down regulated PI3K, pAkt, Akt, vimentin and up regulated RKIP levels. Didymin induced G2/M arrest along with decreasing the levels of cyclin D1, CDK4 and cyclin B1. Importantly, didymin inhibited NMyc as confirmed at protein, mRNA and transcriptional level by promoter-reporter assays. HPLC analysis of didymin (2 mg/kg b.w.) treated mice serum revealed effective oral absorption with free didymin concentration of 2.1 μM. Further in vivo mice xenograft studies revealed that didymin (2 mg/kg b.w.) treated animals had significant reductions in tumors size compared to controls. Didymin strongly inhibited the proliferation (Ki67) and angiogenesis (CD31) markers as well as N-Myc expression as revealed by the histopathological examination of paraffin embedded section of resected tumors. Collectively, our in vitro and in vivo studies elucidated the anti-cancer properties and mechanisms of action of a novel, orally active and palatable flavonoid didymin which makes it a potential new approach for neuroblastoma therapy (NANT) to target pediatric neuroblastomas. PMID:22174364

  12. miR-103 inhibits proliferation and sensitizes hemopoietic tumor cells for glucocorticoid-induced apoptosis

    PubMed Central

    Biton, Moshe; Stepensky, Polina

    2017-01-01

    Glucocorticoid (GC) hormones are an important ingredient of leukemia therapy since they are potent inducers of lymphoid cell apoptosis. However, the development of GC resistance remains an obstacle in GC-based treatment. In the present investigation we found that miR-103 is upregulated in GC-sensitive leukemia cells treated by the hormone. Transfection of GC resistant cells with miR-103 sensitized them to GC induced apoptosis (GCIA), while miR-103 sponging of GC sensitive cells rendered them partially resistant. miR-103 reduced the expression of cyclin dependent kinase (CDK2) and its cyclin E1 target, thereby leading to inhibition of cellular proliferation. miR-103 is encoded within the fifth intron of PANK3 gene. We demonstrate that the GC receptor (GR) upregulates miR-103 by direct interaction with GC response element (GRE) in the PANK3 enhancer. Consequently, miR-103 targets the c-Myc activators c-Myb and DVL1, thereby reducing c-Myc expression. Since c-Myc is a transcription factor of the miR-17~92a poly-cistron, all six miRNAs of the latter are also downregulated. Of these, miR-18a and miR-20a are involved in GCIA, as they target GR and BIM, respectively. Consequently, GR and BIM expression are elevated, thus advancing GCIA. Altogether, this study highlights miR-103 as a useful prognostic biomarker and drug for leukemia management in the future. PMID:27888798

  13. ALDH2 attenuates Dox-induced cardiotoxicity by inhibiting cardiac apoptosis and oxidative stress.

    PubMed

    Gao, Yawen; Xu, Yan; Hua, Songwen; Zhou, Shenghua; Wang, Kangkai

    2015-01-01

    The anthracycline chemotherapy drug doxorubicin (DOX) is cardiotoxic. This study aimed to explore the effect of acetaldehyde dehydrogenase 2 (ALDH2), a detoxifying protein, on DOX-induced cardiotoxicity and unveil the underlying mechanisms. BALB/c mice were randomly divided in four groups: control group (no treatment), DOX group (DOX administration for myocardial damage induction), DOX + Daidzin group (DOX administration + Daidzin, an ALDH2 antagonist) and DOX + Alda-1 group (DOX administration + Alda-1, an ALDH2 agonist). Then, survival, haemodynamic parameters, expression of pro- and anti-apoptosis markers, reactive oxygen species (ROS) and 4-Hydroxynonenal (4-HNE) levels, expression and localization of NADPH oxidase 2 (NOX2) and its cytoplasmic subunit p47(PHOX), and ALDH2 expression and activity were assessed. Mortality rates of 0, 35, 5, and 70% were obtained in the control, DOX, DOX + Alda-1, and DOX + Daidzin groups, respectively, at the ninth weekend. Compared with control animals, DOX treatment resulted in significantly reduced left ventricular systolic pressure (LVSP) and ± dp/dt, and overtly increased left ventricular end-diastolic pressure (LVEDP); increased Bax expression and caspase-3/7 activity, and reduced Bcl-2 expression in the myocardium; increased ROS (about 2 fold) and 4-HNE adduct (3 fold) levels in the myocardium; increased NOX2 protein expression and membrane translocation of P47(PHOX). These effects were aggravated in the DOX + Daidzin group, DOX + Alda-1 treated animals showed partial or complete alleviation. Finally, Daidzin further reduced the DOX-repressed ALDH2 activity, which was partially rescued by Alda-1. These results indicated that ALDH2 attenuates DOX-induced cardiotoxicity by inhibiting oxidative stress, NOX2 expression and activity, and reducing myocardial apoptosis.

  14. Salinomycin inhibits proliferation and induces apoptosis of human nasopharyngeal carcinoma cell in vitro and suppresses tumor growth in vivo

    SciTech Connect

    Wu, Danxin; Zhang, Yu; Huang, Jie; Fan, Zirong; Shi, Fengrong; Wang, Senming

    2014-01-10

    Highlight: •We first evaluated the effect of salinomycin on nasopharyngeal carcinoma (NPC). •Salinomycin could inhibit Wnt/β-catenin signaling and induce apoptosis in NPC. •So salinomycin may be a good potential candidate for the chemotherapy of NPC. -- Abstract: Salinomycin (Sal) is a polyether ionophore antibiotic that has recently been shown to induce cell death in various human cancer cells. However, whether salinomycin plays a functional role in nasopharyngeal carcinoma (NPC) has not been determined to date. The present study investigated the chemotherapeutic efficacy of salinomycin and its molecular mechanisms of action in NPC cells. Salinomycin efficiently inhibited proliferation and invasion of 3 NPC cell lines (CNE-1, CNE-2, and CNE-2/DDP) and activated a extensive apoptotic process that is accompanied by activation of caspase-3 and caspase-9, and decreased mitochondrial membrane potential. Meanwhile, the protein expression level of the Wnt coreceptor lipoprotein receptor related protein 6 (LRP6) and β-catenin was down-regulated, which showed that the Wnt/β-catenin signaling was involved in salinomycin-induced apoptosis of NPC cells. In a nude mouse NPC xenograft model, the anti-tumor effect of salinomycin was associated with the downregulation of β-catenin expression. The present study demonstrated that salinomycin can effectively inhibit proliferation and invasion, and induce apoptosis of NPC cells in vitro and inhibit tumor growth in vivo, probably via the inhibition of Wnt/β-catenin signaling, suggesting salinomycin as a potential candidate for the chemotherapy of NPC.

  15. CacyBP/SIP inhibits Doxourbicin-induced apoptosis of glioma cells due to activation of ERK1/2.

    PubMed

    Tang, Yuan; Zhan, Wenjian; Cao, Tong; Tang, Tianjin; Gao, Yong; Qiu, Zhichao; Fu, Chunling; Qian, Fengyuan; Yu, Rutong; Shi, Hengliang

    2016-03-01

    Calcyclin-binding protein or Siah-1-interacting protein (CacyBP/SIP) was previously reported to promote the proliferation of glioma cells. However, the effect of CacyBP/SIP on apoptosis of glioma is poorly understood. Here, our study shows that CacyBP/SIP plays a role in inhibiting doxorubicin (DOX) induced apoptosis of glioma cells U251 and U87. Overexpression of CacyBP/SIP obviously suppressed the DOX-induced cell apoptosis. On the contrary, silencing of CacyBP/SIP significantly promoted it. Further investigation indicated that inhibition of apoptosis by CacyBP/SIP was relevant to its nuclear translocation in response to the DOX treatment. Importantly, we found that the level of p-ERK1/2 in nuclei was related to the nuclear accumulation of CacyBP/SIP. Finally, the role of CacyBP/SIP was confirmed in vivo in a mouse model with the cell line stably silencing CacyBP/SIP. Taken together, our results suggest that CacyBP/SIP plays an important role in inhibiting apoptosis of glioma cells which might be mediated by ERK1/2 signaling pathway, which will provide some guidance for the treatment of glioma.

  16. Propolis Inhibits UVA-Induced Apoptosis of Human Keratinocyte HaCaT Cells by Scavenging ROS

    PubMed Central

    Kim, Han Bit; Yoo, Byung Sun

    2016-01-01

    Propolis is a resinous material collected by honeybees from several plant sources. This research aimed at showing its protective effect against UVA-induced apoptosis of human keratinocyte HaCaT cells. Using Hoechst staining, it was demonstrated that propolis (5 and 10 μg/mL) significantly inhibited the apoptosis of HaCaT cells induced by UVA-irradiation. Propolis also showed the protective effect against loss of mitochondrial membrane potential induced by UVA-irradiaiton in HaCaT cells. Propolis also inhibited the expression of activated caspase-3 induced by UVA-irradiation. To investigate the role of ROS in UVA-induced apoptosis and protection by propolis, the generation of ROS was determined in cells. The results showed that the generation of ROS was markedly reduced in cells pretreated with propolis. Consequently, propolis protected human keratinocyte HaCaT cells against UVA-induced apoptosis, which might be related to the reduction of ROS generation by UVA-irradiation. PMID:27818737

  17. Titanium dioxide nanoparticles inhibit proliferation and induce morphological changes and apoptosis in glial cells.

    PubMed

    Márquez-Ramírez, Sandra Gissela; Delgado-Buenrostro, Norma Laura; Chirino, Yolanda Irasema; Iglesias, Gisela Gutiérrez; López-Marure, Rebeca

    2012-12-16

    Titanium dioxide nanoparticles (TiO(2) NPs) are widely used in the chemical, electrical and electronic industries. TiO(2) NPs can enter directly into the brain through the olfactory bulb and be deposited in the hippocampus region. We determined the effect of TiO(2) NPs on rat and human glial cells, C6 and U373, respectively. We evaluated proliferation by crystal violet staining, internalization of TiO(2) NPs, and cellular morphology by TEM analysis, as well as F-actin distribution by immunostaining and cell death by detecting active caspase-3 and DNA fragmentation. TiO(2) NPs inhibited proliferation and induced morphological changes that were related with a decrease in immuno-location of F-actin fibers. TiO(2) NPs were internalized and formation of vesicles was observed. TiO(2) NPs induced apoptosis after 96h of treatment. Hence, TiO(2) NPs had a cytotoxic effect on glial cells, suggesting that exposure to TiO(2) NPs could cause brain injury and be hazardous to health.

  18. Betulinic acid protects against ischemia/reperfusion-induced renal damage and inhibits leukocyte apoptosis.

    PubMed

    Ekşioğlu-Demiralp, Emel; Kardaş, E Riza; Ozgül, Seçkin; Yağci, Tayfur; Bilgin, Hüseyin; Sehirli, Ozer; Ercan, Feriha; Sener, Göksel

    2010-03-01

    The possible protective effect of betulinic acid on renal ischemia/reperfusion (I/R) injury was studied. Wistar Albino rats were unilaterally nephrectomized and subjected to 45 min of renal pedicle occlusion followed by 6 h of reperfusion. Betulinic acid (250 mg/kg, i.p.) or saline was administered at 30 min prior to ischemia and immediately before the reperfusion. Creatinine, blood urea nitrogen (BUN), lactate dehydrogenase (LDH) and TNF-alpha as well as the oxidative burst of neutrophil and leukocyte apoptosis were assayed in blood samples. Malondialdehyde (MDA), glutathione (GSH) levels, Na(+), K(+)-ATPase and myeloperoxidase (MPO) activities were determined in kidney tissue which was also analysed microscopically. I/R caused significant increases in blood creatinine, BUN, LDH and TNF-alpha. In the kidney samples of the I/R group, MDA levels and MPO activity were increased significantly, however, GSH levels and Na(+), K(+)-ATPase activity were decreased. Betulinic acid ameliorated the oxidative burst response to both formyl-methionyl-leucyl-phenylalanine (fMLP) and phorbol 12-myristate 13-acetate (PMA) stimuli, normalized the apoptotic response and most of the biochemical indices as well as histopathological alterations induced by I/R. In conclusion, these data suggest that betulinic acid attenuates I/R-induced oxidant responses, improved microscopic damage and renal function by regulating the apoptotic function of leukocytes and inhibiting neutrophil infiltration.

  19. A viral vector expressing hypoxia-inducible factor 1 alpha inhibits hippocampal neuronal apoptosis

    PubMed Central

    Chai, Xiqing; Kong, Weina; Liu, Lingyun; Yu, Wenguo; Zhang, Zhenqing; Sun, Yimin

    2014-01-01

    Hypoxia-inducible factor 1 (HIF-1) attenuates amyloid-beta protein neurotoxicity and decreases apoptosis induced by oxidative stress or hypoxia in cortical neurons. In this study, we constructed a recombinant adeno-associated virus (rAAV) vector expressing the human HIF-1α gene (rAAV-HIF-1α), and tested the assumption that rAAV-HIF-1α represses hippocampal neuronal apoptosis induced by amyloid-beta protein. Our results confirmed that rAAV-HIF-1α significantly reduces apoptosis induced by amyloid-beta protein in primary cultured hippocampal neurons. Direct intracerebral rAAV-HIF-1α administration also induced robust and prolonged HIF-1α production in rat hippocampus. Single rAAV-HIF-1α administration resulted in decreased apoptosis of hippocampal neurons in an Alzheimer's disease rat model established by intracerebroventricular injection of aggregated amyloid-beta protein (25–35). Our in vitro and in vivo findings demonstrate that HIF-1 has potential for attenuating hippocampal neuronal apoptosis induced by amyloid-beta protein, and provides experimental support for treatment of neurodegenerative diseases using gene therapy. PMID:25206774

  20. Ginsenoside Rh2 inhibits proliferation and induces apoptosis in human leukemia cells via TNF-α signaling pathway.

    PubMed

    Huang, Jingjia; Peng, Kunjian; Wang, Linghao; Wen, Bin; Zhou, Lin; Luo, Tiao; Su, Min; Li, Jijia; Luo, Zhiyong

    2016-08-01

    Ginsenoside Rh2, a triterpene saponin extracted from Panax ginseng, exhibits pharmacological activity against multiple cancers. However, the anticancer mechanism of ginsenoside Rh2 is unclear. In this study, we found that ginsenoside Rh2 effectively inhibits growth and induces apoptosis of HL-60 cells. Using microarray technology, we found that tumor necrosis factor-α (TNF-α) is clearly up-regulated. Furthermore, anti-TNF-α antibody relieved the Rh2-induced HL-60 cell apoptosis via suppression of caspase-8, caspase-9, and caspase-3 activation. In addition, TNF-α up-regulation was also observed in other Rh2-treated cancer cell lines. These results demonstrate that TNF-α plays a key role in ginsenoside Rh2-induced cell apoptosis.

  1. Dendropanoxide induces autophagy through ERK1/2 activation in MG-63 human osteosarcoma cells and autophagy inhibition enhances dendropanoxide-induced apoptosis.

    PubMed

    Lee, Ji-Won; Kim, Kyoung-Sook; An, Hyun-Kyu; Kim, Cheorl-Ho; Moon, Hyung-In; Lee, Young-Choon

    2013-01-01

    Anticancer effects of dendropanoxide (DP) newly isolated from leaves and stem of Dendropanax morbifera Leveille were firstly investigated in this study. DP inhibited cell proliferation and induced apoptosis in dose- and time-dependent manner in MG-63 human osteosarcoma cells, which was dependent on the release of cytochrome c to the cytosol and the activation of caspases. Moreover, the DP-treated cells exhibited autophagy, as characterized by the punctuate patterns of microtubule-associated protein 1 light chain 3 (LC3) by confocal microscopy and the appearance of autophagic vacuoles by MDC staining. The expression levels of ATG7, Beclin-1 and LC3-II were also increased by DP treatment. Inhibition of autophagy by 3-methyladenine (3-MA) and wortmannin (Wort) significantly enhanced DP-induced apoptosis. DP treatment also caused a time-dependent increase in protein levels of extracellular signal-regulated kinase 1 and 2 (ERK1/2), and inhibition of ERK1/2 phosphorylation with U0126 resulted in a decreased DP-induced autophagy that was accompanied by an increased apoptosis and a decreased cell viability. These results indicate a cytoprotective function of autophagy against DP-induced apoptosis and suggest that the combination of DP treatment with autophagy inhibition may be a promising strategy for human osteosarcoma control. Taken together, this study demonstrated for the first time that DP could induce autophagy through ERK1/2 activation in human osteosarcoma cells and autophagy inhibition enhanced DP-induced apoptosis.

  2. Manumycin inhibits ras signal transduction pathway and induces apoptosis in COLO320-DM human colon tumourcells

    PubMed Central

    Paolo, A Di; Danesi, R; Nardini, D; Bocci, G; Innocenti, F; Fogli, S; Barachini, S; Marchetti, A; Bevilacqua, G; Tacca, M Del

    2000-01-01

    The aim of the present study was to assess the cytotoxicity of manumycin, a specific inhibitor of farnesyl:protein transferase, as well as its effects on protein isoprenylation and kinase-dependent signal transduction in COLO320-DM human colon adenocarcinoma which harbours a wild-type K- ras gene. Immunoblot analysis of isolated cell membranes and total cellular lysates of COLO320-DM cells demonstrated that manumycin dose-dependently reduced p21 ras farnesylation with a 50% inhibitory concentration (IC50) of 2.51 ± 0.11 μM and 2.68 ± 0.20 μM, respectively, while the geranylgeranylation of p21 rhoA and p21 rap1 was not affected. Manumycin dose-dependently inhibited (IC50= 2.40 ± 0.67 μM) the phosphorylation of the mitogen-activated protein kinase/extracellular-regulated kinase 2 (p42MAPK/ERK2), the main cytoplasmic effector of p21 ras, as well as COLO320-DM cell growth (IC50= 3.58 ± 0.27 μM) without affecting the biosynthesis of cholesterol. Mevalonic acid (MVA, 100 μM), a substrate of the isoprenoid synthesis, was unable to protect COLO320-DM cells from manumycin cytotoxicity. Finally, manumycin 1–25 μM for 24–72 h induced oligonucleosomal fragmentation in a dose- and time-dependent manner and MVA did not protect COLO320-DM cells from undergoing DNA cleavage. The present findings indicate that the inhibition of p21 ras processing and signal transduction by manumycin is associated with marked inhibition of cell proliferation and apoptosis in colon cancer cells and the effect on cell growth does not require the presence of a mutated ras gene for maximal expression of chemotherapeutic activity. © 2000 Cancer Research Campaign PMID:10732765

  3. Targeting receptor for advanced glycation end products (RAGE) expression induces apoptosis and inhibits prostate tumor growth

    SciTech Connect

    Elangovan, Indira; Thirugnanam, Sivasakthivel; Chen, Aoshuang; Zheng, Guoxing; Bosland, Maarten C.; Kajdacsy-Balla, Andre; Gnanasekar, Munirathinam

    2012-01-27

    Highlights: Black-Right-Pointing-Pointer Targeting RAGE by RNAi induces apoptosis in prostate cancer cells. Black-Right-Pointing-Pointer Silencing RAGE expression abrogates rHMGB1 mediated cell proliferation. Black-Right-Pointing-Pointer Down regulation of RAGE by RNAi inhibits PSA secretion of prostate cancer cells. Black-Right-Pointing-Pointer Knock down of RAGE abrogates prostate tumor growth in vivo. Black-Right-Pointing-Pointer Disruption of RAGE expression in prostate tumor activates death receptors. -- Abstract: Expression of receptor for advanced glycation end products (RAGE) plays a key role in the progression of prostate cancer. However, the therapeutic potential of targeting RAGE expression in prostate cancer is not yet evaluated. Therefore in this study, we have investigated the effects of silencing the expression of RAGE by RNAi approach both in vitro and in vivo. The results of this study showed that down regulation of RAGE expression by RNAi inhibited the cell proliferation of androgen-dependent (LNCaP) and androgen-independent (DU-145) prostate cancer cells. Furthermore, targeting RAGE expression resulted in apoptotic elimination of these prostate cancer cells by activation of caspase-8 and caspase-3 death signaling. Of note, the levels of prostate specific antigen (PSA) were also reduced in LNCaP cells transfected with RAGE RNAi constructs. Importantly, the RAGE RNAi constructs when administered in nude mice bearing prostate tumors, inhibited the tumor growth by targeting the expression of RAGE, and its physiological ligand, HMGB1 and by up regulating death receptors DR4 and DR5 expression. Collectively, the results of this study for the first time show that targeting RAGE by RNAi may be a promising alternative therapeutic strategy for treating prostate cancer.

  4. Resveratrol Treatment Inhibits Proliferation of and Induces Apoptosis in Human Colon Cancer Cells

    PubMed Central

    Feng, Miao; Zhong, Lu-Xing; Zhan, Zheng-Yu; Huang, Zhi-Hao; Xiong, Jian-Ping

    2016-01-01

    Background Resveratrol, a natural isolate from plant sources, has a long and important history in traditional Chinese medicine. In the present study we investigated the effect of resveratrol on human colon cancer cell lines. Material/Methods We used the Cell Counting kit-8 (CCK-8) for determination of colon cancer cell viability. Apoptosis induction was analyzed using the DeadEnd™ Colorimetric TUNEL System (Promega, Madison, WI, USA). The siRNA Transfection Reagent kit (Santa Cruz Biotechnology, Inc.) was used for the administration of COX-2 silencer RNA (siRNA) into the colon cancer cells. Primer Express® software for Real-Time PCR ver. 3.0 (Applied Biosystems, Foster City, CA, USA) was used to prepare the primers for RT-PCR. Results The results revealed that exposure of colon cancer cells to resveratrol inhibited cell viability. Resveratrol exhibited a significant inhibitory effect on cell viability at 30 μM concentration after 48 h of exposure. We observed that 30-μM doses of resveratrol for 72 h led to 18, 29, and 34% reduction in the viability of HCA-17, SW480, and HT29 cells, respectively. It also significantly induced apoptosis in both of the tested carcinoma cell lines. The population of apoptotic cells in HCA-17 and SW480 cell lines after 48 h of resveratrol treatment was 59.8±4 and 67.2±4%, respectively, compared to 2.3±1% in the control cells. The colon cancer cells exposed to resveratrol showed significantly lower cyclooxygenase-2 and prostaglandin receptor expression. Treatment of colon cancer cells with the inhibitor of cyclooxygenase-2, indomethacin, and administration of silencer RNA for cyclooxygenase-2 also produced similar results. Conclusions These findings suggest that resveratrol treatment can be a promising strategy for the treatment of colon cancer. PMID:27040803

  5. SIRT1 activator ameliorates the renal tubular injury induced by hyperglycemia in vivo and in vitro via inhibiting apoptosis.

    PubMed

    Wang, Xue-Ling; Wu, Li-Yan; Zhao, Long; Sun, Li-Na; Liu, Hai-Ying; Liu, Gang; Guan, Guang-Ju

    2016-10-01

    We aimed to explore the role of SIRT1 in apoptosis in human kidney proximal tubule epithelial (HK-2) cells, and to determine whether resveratrol (RSV, a SIRT1 activator) could ameliorate apoptosis in rats with streptozotocin-induced diabetes mellitus (DM) and/or in high glucose (HG, 30mM) - stimulated HK-2 cells. Rats were distributed randomly into three groups: 1) control group, 2) DM group, and 3) DM with RSV group (DM+RSV; rats treated with 30mg/kg/d of RSV for 16 weeks). The physical, biochemical, and morphological parameters were then examined. Additionally, the deacetylase activity of SIRT1, and the expression levels of SIRT1 and of representative apoptosis markers, such as p53, acetylated p53, cleaved caspase-3, caspase-9, and cleaved PARP, were measured. HK-2 cells were stimulated by HG for different lengths of time to study the effect of HG on apoptosis. HK-2 cells were treated with or without RSV (25μM) to investigate if RSV has a protective effect on HG-induced apoptosis. A gene-specific small interfering RNA against SIRT1 was used to study the role of SIRT1 in apoptosis. More apoptosis was found in the DM rats than in the control rats. Similarly, the expression levels of cleaved caspase-3, cleaved PARP, and acetylated p53 were significantly higher, and the level of SIRT1 was significantly lower, in the HK-2 cells that were cultured under HG conditions than those in the HK-2 cells that were cultured under low glucose (5.5mM) conditions. Notably, treatment with RSV lessened the HG-induced changes in the levels of apoptosis indicators, and this inhibition of HG-induced apoptosis in HK-2 cells by RSV treatment was abolished by SIRT1 silencing. Our study showed that hyperglycemia contributes to apoptosis in rat kidney and HK-2 cells. SIRT1 activation by RSV can reduce urinary albumin excretion and proximal tubule epithelial apoptosis both in vitro and in vivo. Based on our study, SIRT1/p53 axis played an important role in the hyperglycemia induced apoptosis

  6. Pyrrolidine dithiocarbamate-zinc(II) and -copper(II) complexes induce apoptosis in tumor cells by inhibiting the proteasomal activity

    SciTech Connect

    Milacic, Vesna; Chen Di; Giovagnini, Lorena; Diez, Alejandro; Fregona, Dolores; Dou, Q. Ping

    2008-08-15

    Zinc and copper are trace elements essential for proper folding, stabilization and catalytic activity of many metalloenzymes in living organisms. However, disturbed zinc and copper homeostasis is reported in many types of cancer. We have previously demonstrated that copper complexes induced proteasome inhibition and apoptosis in cultured human cancer cells. In the current study we hypothesized that zinc complexes could also inhibit the proteasomal chymotrypsin-like activity responsible for subsequent apoptosis induction. We first showed that zinc(II) chloride was able to inhibit the chymotrypsin-like activity of a purified 20S proteasome with an IC{sub 50} value of 13.8 {mu}M, which was less potent than copper(II) chloride (IC{sub 50} 5.3 {mu}M). We then compared the potencies of a pyrrolidine dithiocarbamate (PyDT)-zinc(II) complex and a PyDT-copper(II) complex to inhibit cellular proteasomal activity, suppress proliferation and induce apoptosis in various human breast and prostate cancer cell lines. Consistently, zinc complex was less potent than copper complex in inhibiting the proteasome and inducing apoptosis. Additionally, zinc and copper complexes appear to use somewhat different mechanisms to kill tumor cells. Zinc complexes were able to activate calpain-, but not caspase-3-dependent pathway, while copper complexes were able to induce activation of both proteases. Furthermore, the potencies of these PyDT-metal complexes depend on the nature of metals and also on the ratio of PyDT to the metal ion within the complex, which probably affects their stability and availability for interacting with and inhibiting the proteasome in tumor cells.

  7. NSAIDs induce apoptosis in nonproliferating ovarian cancer cells and inhibit tumor growth in vivo.

    PubMed

    Duncan, Kristal; Uwimpuhwe, Henriette; Czibere, Akos; Sarkar, Devanand; Libermann, Towia A; Fisher, Paul B; Zerbini, Luiz F

    2012-07-01

    Ovarian cancer (OC) is one of the most lethal gynaecological cancers, which usually has a poor prognosis due to late diagnosis. A large percentage of the OC cell population is in a nonproliferating and quiescent stage, which poses a barrier to success when using most chemotherapeutic agents. Recent studies have shown that several nonsteroidal anti-inflammatory drugs (NSAIDs) are effective in the treatment of OC. Furthermore, we have previously described the molecular mechanisms of NSAIDs' induction of cancer apoptosis. In this report, we evaluated various structurally distinct NSAIDs for their efficacies in inducing apoptosis in nonproliferating OC cells. Although several NSAIDs-induced apoptosis, Flufenamic Acid, Flurbiprofen, Finasteride, Celocoxib, and Ibuprofen were the most potent NSAIDs inducing apoptosis. A combination of these agents resulted in an enhanced effect. Furthermore, we demonstrate that the combination of Flurbiprofen, which targets nonproliferative cells, and Sulindac Sulfide, that affects proliferative cells, strongly reduced tumor growth when compared with a single agent treatment. Our data strongly support the hypothesis that drug treatment regimens that target nonproliferating and proliferating cells may have significant efficacy against OC. These results also provide a rationale for employing compounds or even chemically modified NSAIDs, which selectively and efficiently induce apoptosis in cells during different stages of the cell cycle, to design more potent anticancer drugs.

  8. Clitocine targets Mcl-1 to induce drug-resistant human cancer cell apoptosis in vitro and tumor growth inhibition in vivo.

    PubMed

    Sun, Jian-Guo; Li, Hua; Li, Xia; Zeng, Xueli; Wu, Ping; Fung, Kwok-Pui; Liu, Fei-Yan

    2014-05-01

    Drug resistance is a major reason for therapy failure in cancer. Clitocine is a natural amino nucleoside isolated from mushroom and has been shown to inhibit cancer cell proliferation in vitro. In this study, we observed that clitocine can effectively induce drug-resistant human cancer cell apoptosis in vitro and inhibit tumor xenograft growth in vivo. Clitocine treatment inhibited drug-resistant human cancer cell growth in vitro in a dose- and time-dependent manner. Biochemical analysis revealed that clitocine-induced tumor growth inhibition is associated with activation of caspases 3, 8 and 9, PARP cleavage, cytochrome c release and Bax, Bak activation, suggesting that clitocine inhibits drug-resistant cancer cell growth through induction of apoptosis. Analysis of apoptosis regulatory genes indicated that Mcl-1 level was dramatically decreased after clitocine treatment. Over-expression of Mcl-1 reversed the activation of Bax and attenuated clitocine-induced apoptosis, suggesting that clitocine-induced apoptosis was at least partially by inducing Mcl-1 degradation to release Bax and Bak. Consistent with induction of apoptosis in vitro, clitocine significantly suppressed the drug-resistant hepatocellular carcinoma xenograft growth in vivo by inducing apoptosis as well as inhibiting cell proliferation. Taken together, our data demonstrated that clitocine is a potent Mcl-1 inhibitor that can effectively induce apoptosis to suppress drug-resistant human cancer cell growth both in vitro and in vivo, and thus holds great promise for further development as potentially a novel therapeutic agent to overcome drug resistance in cancer therapy.

  9. Nitidine chloride inhibits proliferation and induces apoptosis in colorectal cancer cells by suppressing the ERK signaling pathway

    PubMed Central

    ZHAI, HUIYUAN; HU, SANYUAN; LIU, TONGXIANG; WANG, FENG; WANG, XIXUN; WU, GUOCHANG; ZHANG, YIFEI; SUI, MINGHUA; LIU, HUANTAO; JIANG, LIXIN

    2016-01-01

    Nitidine chloride (NC) is a natural bioactive phytochemical alkaloid that has displayed anticancer activity in various types of cancer. However, no evidence has been reported for the direct effect of NC on CRC cell proliferation and apoptosis, and the underling mechanisms to be fully elucidated. The present study aimed to investigate the influence of NC on the apoptosis and proliferation of CRC cells. The viability and proliferation of CRC cells was measured by MTT assay and a [3H] thymidine uptake assay. Apoptosis was measured using a flow cytometric apoptosis assay and TUNEL staining. The expression levels of apoptotic-regulated proteins in addition to extracellular signal-regulated kinase (ERK) were measured by western blot analysis following stimulation with NC. The results indicated that NC inhibited the proliferation of HCT116 cells in a dose- and time-dependent manner. Additionally, apoptotic induction by NC treatment was confirmed. Furthermore, NC was demonstrated to significantly upregulate the expression of Bax, p53, cleaved caspase-3 and -9 and downregulate the expression of Bcl-2. Treatment with NC reduced the phosphorylation of ERK and by using an ERK inhibitor, U0126, the roles of NC in apoptotic induction and the inhibition of proliferation were further demonstrated. These results demonstrated that NC inhibited the proliferation and induced the apoptosis of CRC cells via the ERK signaling pathway. PMID:26847477

  10. Inhibition of Mitochondrial Clearance and Cu/Zn-SOD Activity Enhance 6-Hydroxydopamine-Induced Neuronal Apoptosis.

    PubMed

    In, Sua; Hong, Chang-Won; Choi, Boyoung; Jang, Bong-Geum; Kim, Min-Ju

    2016-01-01

    Parkinson's disease (PD) is a common movement disorder among neurodegenerative diseases, involving neuronal cell death in the substantia nigra of the midbrain. Although mechanisms of cell death in PD have been studied, the exact molecular pathogenesis is still unclear. Here, we explore the relationship between two types of cell death, autophagy and apoptosis, which have been studied separately in parkinsonian mimetic model of 6-hydroxydopamine (6-OHDA). 6-OHDA induced autophagy firstly and then later inhibition of autophagy flux occurred with apoptosis. The apoptosis was prevented by treatment of pan-caspase inhibitor, zVAD-fmk (benzyloxycarbonyl-VAD-fluoromethylketone (zVAD)), or early phase inhibitor of autophagy, 3-methyladenine (3-MA), indicating that autophagic induction was followed by the apoptosis. Interestingly, late step inhibitor of autophagy, bafilomycin A1 (BafA), aggravated 6-OHDA-induced apoptosis. This was associated with mitochondrial abnormality such as the inhibition of damaged mitochondrial clearance and aberrant increase of extracellular oxygen consumption. Furthermore, treatment of BafA did not inhibit 6-OHDA-mediated superoxide formation but strongly reduced the hydrogen peroxide production to below basal levels, indicating failure from superoxide to hydrogen peroxide. These results were accompanied by a lowered expression and activity of copper/zinc superoxide dismutase (Cu/Zn-SOD) but not of manganese SOD (MnSOD) and catalase. Thus, the present study suggests that crosstalk among apoptosis, autophagy, and oxidative stress is a causative factor of 6-OHDA-induced neuronal death and provides a mechanistic understanding of PD pathogenesis.

  11. Xanthohumol induces growth inhibition and apoptosis in ca ski human cervical cancer cells.

    PubMed

    Yong, Wai Kuan; Abd Malek, Sri Nurestri

    2015-01-01

    We investigate induction of apoptosis by xanthohumol on Ca Ski cervical cancer cell line. Xanthohumol is a prenylated chalcone naturally found in hop plants, previously reported to be an effective anticancer agent in various cancer cell lines. The present study showed that xanthohumol was effective to inhibit proliferation of Ca Ski cells based on IC50 values using sulforhodamine B (SRB) assay. Furthermore, cellular and nuclear morphological changes were observed in the cells using phase contrast microscopy and Hoechst/PI fluorescent staining. In addition, 48-hour long treatment with xanthohumol triggered externalization of phosphatidylserine, changes in mitochondrial membrane potential, and DNA fragmentation in the cells. Additionally, xanthohumol mediated S phase arrest in cell cycle analysis and increased activities of caspase-3, caspase-8, and caspase-9. On the other hand, Western blot analysis showed that the expression levels of cleaved PARP, p53, and AIF increased, while Bcl-2 and XIAP decreased in a dose-dependent manner. Taken together, these findings indicate that xanthohumol-induced cell death might involve intrinsic and extrinsic apoptotic pathways, as well as downregulation of XIAP, upregulation of p53 proteins, and S phase cell cycle arrest in Ca Ski cervical cancer cells. This work suggests that xanthohumol is a potent chemotherapeutic candidate for cervical cancer.

  12. Xanthohumol Induces Growth Inhibition and Apoptosis in Ca Ski Human Cervical Cancer Cells

    PubMed Central

    2015-01-01

    We investigate induction of apoptosis by xanthohumol on Ca Ski cervical cancer cell line. Xanthohumol is a prenylated chalcone naturally found in hop plants, previously reported to be an effective anticancer agent in various cancer cell lines. The present study showed that xanthohumol was effective to inhibit proliferation of Ca Ski cells based on IC50 values using sulforhodamine B (SRB) assay. Furthermore, cellular and nuclear morphological changes were observed in the cells using phase contrast microscopy and Hoechst/PI fluorescent staining. In addition, 48-hour long treatment with xanthohumol triggered externalization of phosphatidylserine, changes in mitochondrial membrane potential, and DNA fragmentation in the cells. Additionally, xanthohumol mediated S phase arrest in cell cycle analysis and increased activities of caspase-3, caspase-8, and caspase-9. On the other hand, Western blot analysis showed that the expression levels of cleaved PARP, p53, and AIF increased, while Bcl-2 and XIAP decreased in a dose-dependent manner. Taken together, these findings indicate that xanthohumol-induced cell death might involve intrinsic and extrinsic apoptotic pathways, as well as downregulation of XIAP, upregulation of p53 proteins, and S phase cell cycle arrest in Ca Ski cervical cancer cells. This work suggests that xanthohumol is a potent chemotherapeutic candidate for cervical cancer. PMID:25949267

  13. Natural compound oblongifolin C inhibits autophagic flux, and induces apoptosis and mitochondrial dysfunction in human cholangiocarcinoma QBC939 cells

    PubMed Central

    Zhang, Aiqing; He, Wei; Shi, Huimin; Huang, Xiaodan; Ji, Guozhong

    2016-01-01

    The compounds, which are obtained from natural plants or microbes may offer potential as one of the strategies for the management of cholangiocarcinoma. Oblongifolin C (OC), a natural small molecule compound extracted and purified from Garcinia yunnanensis Hu, can activate the mitochondrial apoptotic pathway in human cervical cancer cells. However, the direct effects of OC on cholangiocarcinoma cells are not well defined. The effect of OC on cell apoptosis and its underlying mechanisms were investigated in cultured QBC939 cells by the methyl thiazol tetrazolium assay, mitochondrial membrane potential, ATP content and western blot analysis. The present study reported that the in vitro treatment of human cholangiocarcinoma QBC939 cells with different concentrations (5, 10, 20 and 40 μM) of OC decreased cell viability and induced apoptosis in a dose-dependent manner. The results of the present study also showed that OC-induced QBC939 cell apoptosis was mediated through the inhibition of autophagy and mitochondrial dysfunction (MtD). Additionally, inhibiting autophagy increased OC-induced apoptosis and MtD, whereas exposure to the autophagy inducer, rapmycin, attenuated these changes. Together, the results of the present study are the first, to the best of our knowledge, to identify OC as a chemotherapeutic agent against human cholangiocarcinoma QBC939 cells in vitro via the regulation of autophagy and MtD. PMID:27499017

  14. SOX6 and PDCD4 enhance cardiomyocyte apoptosis through LPS-induced miR-499 inhibition.

    PubMed

    Jia, Zhuqing; Wang, Jiaji; Shi, Qiong; Liu, Siyu; Wang, Weiping; Tian, Yuyao; Lu, Qin; Chen, Ping; Ma, Kangtao; Zhou, Chunyan

    2016-02-01

    Sepsis-induced cardiac apoptosis is one of the major pathogenic factors in myocardial dysfunction. As it enhances numerous proinflammatory factors, lipopolysaccharide (LPS) is considered the principal mediator in this pathological process. However, the detailed mechanisms involved are unclear. In this study, we attempted to explore the mechanisms involved in LPS-induced cardiomyocyte apoptosis. We found that LPS stimulation inhibited microRNA (miR)-499 expression and thereby upregulated the expression of SOX6 and PDCD4 in neonatal rat cardiomyocytes. We demonstrate that SOX6 and PDCD4 are target genes of miR-499, and they enhance LPS-induced cardiomyocyte apoptosis by activating the BCL-2 family pathway. The apoptosis process enhanced by overexpression of SOX6 or PDCD4, was rescued by the cardiac-abundant miR-499. Overexpression of miR-499 protected the cardiomyocytes against LPS-induced apoptosis. In brief, our results demonstrate the existence of a miR-499-SOX6/PDCD4-BCL-2 family pathway in cardiomyocytes in response to LPS stimulation.

  15. NF-{kappa}B inhibition is involved in tobacco smoke-induced apoptosis in the lungs of rats

    SciTech Connect

    Zhong Caiyun; Zhou Yamei; Pinkerton, Kent E.

    2008-07-15

    Apoptosis is a vital mechanism for the regulation of cell turnover and plays a critical role in tissue homeostasis and development of many disease processes. Previous studies have demonstrated the apoptotic effect of tobacco smoke; however, the molecular mechanisms by which tobacco smoke triggers apoptosis remain unclear. In the present study we investigated the effects of tobacco smoke on the induction of apoptosis in the lungs of rats and modulation of nuclear factor-kappa B (NF-{kappa}B) in this process. Exposure of rats to 80 mg/m{sup 3} tobacco smoke significantly induced apoptosis in the lungs. Tobacco smoke resulted in inhibition of NF-{kappa}B activity, noted by suppression of inhibitor of {kappa}B (I{kappa}B) kinase (IKK), accumulation of I{kappa}B{alpha}, decrease of NF-{kappa}B DNA binding activity, and downregulation of NF-{kappa}B-dependent anti-apoptotic proteins, including Bcl-2, Bcl-xl, and inhibitors of apoptosis. Initiator caspases for the death receptor pathway (caspase 8) and the mitochondrial pathway (caspase 9) as well as effector caspase 3 were activated following tobacco smoke exposure. Tobacco smoke exposure did not alter the levels of p53 and Bax proteins. These findings suggest the role of NF-{kappa}B pathway in tobacco smoke-induced apoptosis.

  16. Ursodeoxycholic acid protects colon cancer HCT116 cells from deoxycholic acid-induced apoptosis by inhibiting apoptosome formation.

    PubMed

    Saeki, Tohru; Yui, Satoko; Hirai, Tadashi; Fujii, Takami; Okada, Sawami; Kanamoto, Ryuhei

    2012-01-01

    We previously demonstrated that ursodeoxycholic acid (UDC) requires prolonged (≥5 h) preincubation to exhibit effective protection of colon cancer HCT116 cells from deoxycholic acid (DC)-induced apoptosis. Although UDC diminished DC-mediated caspase-9 activation, cytochrome c release from the mitochondria was not inhibited, indicating that UDC acts on the steps of caspase-9 activation. In the present study, therefore, we investigated the effects of UDC on the factors involved in caspase-9 activation. We found that UDC had no significant effect on the expression of antiapoptotic XIAP. Furthermore, UDC did not affect the expression or release of proapoptotic Smac/DIABLO, or the association of XIAP and Smac/DIABLO. In contrast, association of Apaf-1 and caspase-9 stimulated by 500 μM DC was inhibited by UDC pretreatment. Although UDC caused remarkable activation of Akt/PKB, phosphatidylinositol-3-kinase (PI3K) inhibitor did not significantly reduce UDC-mediated cytoprotection. Furthermore, phosphorylation of threonine residues on caspase-9 after UDC pretreatment could not be detected. UDC-mediated cytoprotection was independent of the MAPK pathway, and cyclic AMP (cAMP) analogue did not inhibit DC-induced apoptosis. Our results indicate that UDC protects colon cancer cells from apoptosis induced by hydrophobic bile acids, by inhibiting apoptosome formation independently of the survival signals mediated by the PI3K, MAPK, or cAMP pathways.

  17. Cordycepin induces human lung cancer cell apoptosis by inhibiting nitric oxide mediated ERK/Slug signaling pathway

    PubMed Central

    Hwang, Jung Hoo; Park, Soo Jung; Ko, Won Gyu; Kang, Seong-Mun; Lee, Da Bin; Bang, Junho; Park, Byung-Joo; Wee, Chung-Beum; Kim, Dae Joon; Jang, Ik-Soon; Ko, Jae-Hong

    2017-01-01

    Nitric oxide (NO) is an important signaling molecule and a component of the inflammatory cascade. Besides, it is also involved in tumorigenesis. Aberrant upregulation and activation of the ERK cascade by NO often leads to tumor cell development. However, the role of ERK inactivation induced by the negative regulation of NO during apoptosis is not completely understood. In this study, treatment of A549 and PC9 human lung adenocarcinoma cell lines with cordycepin led to a reduction in their viability. Analysis of the effect of cordycepin treatment on ERK/Slug signaling activity in the A549 cell line revealed that LPS-induced inflammatory microenvironments could stimulate the expression of TNF-α, CCL5, IL-1β, IL-6, IL-8 and upregulate NO, phospho-ERK (p-ERK), and Slug expression. In addition, constitutive expression of NO was observed. Cordycepin inhibited LPS-induced stimulation of iNOS, NO, p-ERK, and Slug expression. L-NAME, an inhibitor of NOS, inhibited p-ERK and Slug expression. It was also found that cordycepin-mediated inhibition of ERK downregulated Slug, whereas overexpression of ERK led to an upregulation of Slug levels in the cordycepin-treated A549 cells. Inhibition of Slug by siRNA induced Bax and caspase-3, leading to cordycepin-induced apoptosis. Cordycepin-mediated inhibition of ERK led to a reduction in phospho-GSK3β (p-GSK3β) and Slug levels, whereas LiCl, an inhibitor of GSK3β, upregulated p-GSK3β and Slug. Overall, the results obtained indicate that cordycepin inhibits the ERK/Slug signaling pathway through the activation of GSK3β which, in turn, upregulates Bax, leading to apoptosis of the lung cancer cells.

  18. Autophagy inhibition enhances silibinin-induced apoptosis by regulating reactive oxygen species production in human prostate cancer PC-3 cells.

    PubMed

    Kim, Sang-Hun; Kim, Kwang-Youn; Yu, Sun-Nyoung; Park, Seul-Ki; Choi, Hyeun-Deok; Ji, Jae-Hoon; Ahn, Soon-Cheol

    Silibinin is a major bioactive component of silymarin and has anticancer effects on cancer cell line and has been used as a supportive therapy for chronic inflammatory liver condition. These anticancer effects of silibinin have been demonstrated both in vitro and in vivo cancer models. Although various evidences showed apoptosis signaling pathways by silibinin, there is no report to address the clearly mechanism of silibinin-induced autophagy in prostate cancer PC-3 cells. Our study showed that silibinin triggered autophagy through up-regulation of microtubule-associated protein 1 light chain 3 (LC3)-II, formation of acidic vesicular organelles (AVO) and punctuate of GFP-LC3, which was inhibited by 3-methyladenine (3-MA), an inhibitor of specific autophagy. In addition, silibinin induced autophagy through production of reactive oxygen species (ROS). Inhibition of ROS with diphenyleneiodonium (DPI), a ROS inhibitor, attenuated silibinin-triggered autophagy. Inhibition of autophagy with 3-MA enhanced the silibinin-induced apoptosis through the regulation of caspase-3 and PARP. These results suggested that silibinin induced autophagy by regulating ROS and its mechanism played a protective role against apoptosis in PC-3 cells.

  19. Antitumor Indolequinones Induced Apoptosis in Human Pancreatic Cancer Cells via Inhibition of Thioredoxin Reductase and Activation of Redox Signaling

    PubMed Central

    Yan, Chao; Siegel, David; Newsome, Jeffery; Chilloux, Aurelie; Moody, Christopher J.

    2012-01-01

    Indolequinones (IQs) were developed as potential antitumor agents against human pancreatic cancer. IQs exhibited potent antitumor activity against the human pancreatic cancer cell line MIA PaCa-2 with growth inhibitory IC50 values in the low nanomolar range. IQs were found to induce time- and concentration-dependent apoptosis and to be potent inhibitors of thioredoxin reductase 1 (TR1) in MIA PaCa-2 cells at concentrations equivalent to those inducing growth-inhibitory effects. The mechanism of inhibition of TR1 by the IQs was studied in detail in cell-free systems using purified enzyme. The C-terminal selenocysteine of TR1 was characterized as the primary adduction site of the IQ-derived reactive iminium using liquid chromatography-tandem mass spectrometry analysis. Inhibition of TR1 by IQs in MIA PaCa-2 cells resulted in a shift of thioredoxin-1 redox state to the oxidized form and activation of the p38/c-Jun NH2-terminal kinase (JNK) mitogen-activated protein kinase (MAPK) signaling pathway. Oxidized thioredoxin is known to activate apoptosis signal-regulating kinase 1, an upstream activator of p38/JNK in the MAPK signaling cascade and this was confirmed in our study providing a potential mechanism for IQ-induced apoptosis. These data describe the redox and signaling events involved in the mechanism of growth inhibition induced by novel inhibitors of TR1 in human pancreatic cancer cells. PMID:22147753

  20. Inhibition of microRNA-14 contributes to actinomycin-D-induced apoptosis in the Sf9 insect cell line.

    PubMed

    Kumarswamy, Regalla; Chandna, Sudhir

    2010-08-01

    Actinomycin-D (Act-D) and other inhibitors of RNA synthesis induce extensive and rapid apoptosis in the lepidopteran insect cells. Interestingly, a similar effect is not observed in the case of protein synthesis shutdown, implying that certain RNA species may be critically required for cell survival. In order to assess whether depletion of certain anti-apoptotic microRNAs may result in insect cell apoptosis induced by these transcriptional inhibitors, we inhibited two antiapoptotic microRNAs, viz. bantam and miR-14 (microRNA-14), with known functions in insect systems, by transfecting lepidopteran Sf9 cell line (derived from Spodoptera frugiperda) with sequence-specific inhibitory anti-miRs. Our results indicate that miR-14 is indeed required for constitutive cell survival as its inhibition caused considerable apoptosis. Importantly, exogenous supplementation with the mimics of miR-14 precursor molecules could partially inhibit the Act-D-induced Sf9 cell death. Further, our results indicate that miR-14 may function downstream of mitochondrial cytochrome c release in preventing Act-D-induced apoptosis, implying possible inhibitory interactions with caspases as reported previously in other organisms. While the microRNA species are known to regulate cell death in Drosophila, which belongs the insect order Diptera, the present study demonstrates a definitive antiapoptotic role of miR-14 in lepidopteran apoptosis as well. Our study also indicates that additional microRNA species may be regulating lepidopteran cell survival and death, thus warranting further in-depth investigations into these important mechanisms of cell death. Since lepidopteran cells are an excellent model for general stress resistance, this study presents important information about their stress response mechanisms.

  1. Peptide bioregulators inhibit apoptosis.

    PubMed

    Khavinson, V K; Kvetnoii, I M

    2000-12-01

    The effects of peptide bioregulators epithalon and vilon on the dynamics of irradiation-induced apoptotic death of spleen lymphocytes in rats indicate that these agents inhibit physiologically programmed cell death. The antiapoptotic effect of vilon was more pronounced, which corroborates the concept on tissue-specific effect of peptide bioregulators.

  2. Inhibition of H3K9 methyltransferase G9a induces autophagy and apoptosis in oral squamous cell carcinoma

    SciTech Connect

    Ren, Aishu; Qiu, Yu; Cui, Hongjuan; Fu, Gang

    2015-03-27

    Objective: To explore whether inhibition of H3K9 Methyltransferase G9a could exert an antitumoral effect in oral squamous cell carcinoma (OSCC). Materials and methods: First we checked G9a expression in two OSCC cell lines Tca8113 and KB. Next we used a special G9a inhibitor BIX01294 (BIX) to explore the effect of inhibition of G9a on OSCC in vitro. Cell growth was tested by typlan blue staining, MTT assay and Brdu immunofluorescence staining. Cell autophagy was examined by monodansylcadaverine (MDC) staining, LC3-II immunofluorescence staining and LC3-II western blot assay. Cell apoptosis was checked by FITC Annexin-V and PI labeling, tunnel staining and caspase 3 western blot assay. Finally, the effect of inhibition of G9a on clonogenesis and tumorigenesis capacity of OSCC was analyzed by soft agar growth and xenograft model. Results: Here we showed that G9a was expressed in both Tca8113 and KB cells. Inhibition of G9a using BIX significantly reduced cell growth and proliferation in Tca8113 and KB. Inhibition of G9a induced cell autophagy with conversion of LC3-I to LC3-II and cell apoptosis with the expression of cleaved caspase 3. We also found that inhibition of G9a reduced colony formation in soft agar and repressed tumor growth in mouse xenograph model. Conclusion: Our results suggested that G9a might be a potential epigenetic target for OSCC treatment. - Highlights: • Inhibition of G9a reduced cell growth and proliferation in OSCC cells. • Inhibition of G9a induces autophagy and apoptosis in OSCC cells. • Inhibition of G9a repressed tumor growth in mouse xenograph model.

  3. Dexmedetomidine attenuates lipopolysaccharide-induced acute lung injury by inhibiting oxidative stress, mitochondrial dysfunction and apoptosis in rats

    PubMed Central

    Fu, Chunlai; Dai, Xingui; Yang, You; Lin, Mengxiang; Cai, Yeping; Cai, Shaoxi

    2016-01-01

    Previous studies have identified that dexmedetomidine (DEX) treatment can ameliorate the acute lung injury (ALI) induced by lipopolysaccharide and ischemia-reperfusion. However, the molecular mechanisms by which DEX ameliorates lung injury remain unclear. The present study investigated whether DEX, which has been reported to exert effects on oxidative stress, mitochondrial permeability transition pores and apoptosis in other disease types, can exert protective effects in lipopolysaccharide (LPS)-induced ALI by inhibiting oxidative stress, mitochondrial dysfunction and mitochondrial-dependent apoptosis. It was revealed that LPS-challenged rats exhibited significant lung injury, characterized by the deterioration of histopathology, vascular hyperpermeability, wet-to-dry weight ratio and oxygenation index (PaO2/FIO2), which was attenuated by DEX treatment. DEX treatment inhibited LPS-induced mitochondrial dysfunction, as evidenced by alleviating the cellular ATP and mitochondrial membrane potential in vitro. In addition, DEX treatment markedly prevented the LPS-induced mitochondrial-dependent apoptotic pathway in vitro (increases of cell apoptotic rate, cytosolic cytochrome c, and caspase 3 activity) and in vivo (increases of |terminal deoxynucleotidyl transferase dUTP nick-end labeling positive cells, cleaved caspase 3, Bax upregulation and Bcl-2 downregulation). Furthermore, DEX treatment markedly attenuated LPS-induced oxidative stress, as evidenced by downregulation of cellular reactive oxygen species in vitro and lipid peroxides in serum. Collectively, the present results demonstrated that DEX ameliorates LPS-induced ALI by reducing oxidative stress, mitochondrial dysfunction and mitochondrial-dependent apoptosis. PMID:27959438

  4. Dexmedetomidine attenuates lipopolysaccharide-induced acute lung injury by inhibiting oxidative stress, mitochondrial dysfunction and apoptosis in rats.

    PubMed

    Fu, Chunlai; Dai, Xingui; Yang, You; Lin, Mengxiang; Cai, Yeping; Cai, Shaoxi

    2017-01-01

    Previous studies have identified that dexmedetomidine (DEX) treatment can ameliorate the acute lung injury (ALI) induced by lipopolysaccharide and ischemia-reperfusion. However, the molecular mechanisms by which DEX ameliorates lung injury remain unclear. The present study investigated whether DEX, which has been reported to exert effects on oxidative stress, mitochondrial permeability transition pores and apoptosis in other disease types, can exert protective effects in lipopolysaccharide (LPS)‑induced ALI by inhibiting oxidative stress, mitochondrial dysfunction and mitochondrial‑dependent apoptosis. It was revealed that LPS‑challenged rats exhibited significant lung injury, characterized by the deterioration of histopathology, vascular hyperpermeability, wet‑to‑dry weight ratio and oxygenation index (PaO2/FIO2), which was attenuated by DEX treatment. DEX treatment inhibited LPS‑induced mitochondrial dysfunction, as evidenced by alleviating the cellular ATP and mitochondrial membrane potential in vitro. In addition, DEX treatment markedly prevented the LPS‑induced mitochondrial‑dependent apoptotic pathway in vitro (increases of cell apoptotic rate, cytosolic cytochrome c, and caspase 3 activity) and in vivo (increases of |terminal deoxynucleotidyl transferase dUTP nick‑end labeling positive cells, cleaved caspase 3, Bax upregulation and Bcl‑2 downregulation). Furthermore, DEX treatment markedly attenuated LPS‑induced oxidative stress, as evidenced by downregulation of cellular reactive oxygen species in vitro and lipid peroxides in serum. Collectively, the present results demonstrated that DEX ameliorates LPS‑induced ALI by reducing oxidative stress, mitochondrial dysfunction and mitochondrial-dependent apoptosis.

  5. Sirt 1 activator inhibits the AGE-induced apoptosis and p53 acetylation in human vascular endothelial cells.

    PubMed

    Li, Peng; Zhang, Lina; Zhou, Changyong; Lin, Nan; Liu, Aiguo

    2015-01-01

    Advanced glycation end products (AGEs) by nonenzymatic glycation reactions are extremely accumulated in the diabetic vascular cells, neurons, and glia, and are confirmed to play important role in the pathogenesis of diabetes mellitus -induced cardiovascular complications. Sirt 1, known as mammalian sirtuin, has been recognized to regulate insulin secretion and protect cells against oxidative stress, which is promoted by the accumulated AGEs in cardiovascular cells. In the present study, we treated human endothelial Eahy926 cells with AGEs, and determined the apoptosis induction, caspase activation, the Sirt 1 activity, the expression and acetylation of p53. Then we manipulated Sirt 1 activity with a Sirt 1 activator, Resveratrol (RSV), and a Sirt 1 inhibitor, sirtinol, in the AGE-BSA-treated Eahy926 cells, and then re-evaluated the apoptosis induction, caspase activation, the expression and acetylation of p53. Results demonstrated that AGEs induced apoptosis in the human endothelial Eahy926 cells, by promoting the cytochrome c release, activation of caspase 9/3. Also, the AGE-BSA treatment promoted the total p53 level and acetylated (Ac) p53, but reduced the Sirt 1 level and activity. On the other hand, the Sirt 1 inhibitor/activator not only deteriorated/ameliorated the promotion to p53 level and Ac p53, but also aggravated/inhibited the AGE-induced apoptosis and the promotion to apoptosis-associated signaling molecules. In conclusion, the present study confirmed the apoptosis promotion by AGEs in endothelial Eahy926 cells, by regulating the Sirt 1 activity and p53 signaling, it also implies the protective role of Sirt 1 activator against the AGE-induced apoptosis.

  6. Inhibition of Hepatocyte Apoptosis: An Important Mechanism of Corn Peptides Attenuating Liver Injury Induced by Ethanol.

    PubMed

    Ma, Zhili; Hou, Tao; Shi, Wen; Liu, Weiwei; He, Hui

    2015-09-11

    In this study, the effects of mixed corn peptides and synthetic pentapeptide (QLLPF) on hepatocyte apoptosis induced by ethanol were investigated in vivo. QLLPF, was previously characterized from corn protein hydrolysis, which had been shown to exert good facilitating alcohol metabolism activity. Mice were pre-treated with the mixed corn peptides and the pentapeptide for 1 week and then treated with ethanol. After treatment of three weeks, the biochemical indices and the key ethanol metabolizing enzymes, the serum TNF-α, liver TGF-β1 concentrations and the protein expressions related to apoptosis were determined. We found that the Bcl-2, Bax and cytochrome c expressions in the intrinsic pathway and the Fas, FasL and NF-κB expressions in the extrinsic pathway together with higher TNF-α and TGF-β1 concentrations were reversed compared with the model group by both the mixed corn peptides and the pentapeptide. The activation of caspase3 was also suppressed. Additionally, apoptosis was further confirmed with terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and the TUNEL assay demonstrated peptides suppressed hepatocyte apoptosis. Our results suggest that apoptosis induced by ethanol is alleviated in response to the treatment of corn peptides, potentially due to reversing the related protein expression.

  7. Globular adiponectin inhibits ethanol-induced apoptosis in HepG2 cells through heme oxygenase-1 induction.

    PubMed

    Nepal, Saroj; Kim, Mi Jin; Subedi, Amit; Lee, Eung-Seok; Yong, Chul Soon; Kim, Jung-Ae; Kang, WonKu; Kwak, Mi-Kyung; Arya, Dharamvir Singh; Park, Pil-Hoon

    2012-10-01

    Hepatocellular apoptosis is an essential pathological feature of alcoholic liver disease. Adiponectin, an adipokine predominantly secreted from adipose tissue, has been shown to play beneficial roles in alcoholic liver disease against various inflammatory and pro-apoptotic molecules. However, the effects of adiponectin on ethanol-induced apoptosis in liver cells are largely unknown. Herein, we investigated the role of globular adiponectin (gAcrp) in the prevention of ethanol-induced apoptosis and further tried to decipher the potential mechanisms involved. In the present study, we demonstrated that gAcrp significantly inhibits both ethanol-induced increase in Fas ligand expression and activation of caspase-3 in human hepatoma cell lines (HepG2 cells), suggesting that gAcrp plays a protective role against ethanol-induced apoptosis in liver cells. This protective effect of gAcrp was mediated through adiponectin receptor R1 (adipoR1). Further, globular adiponectin treatment caused induction of heme oxygenase-1 (HO-1) through, at least in part, nuclear factor (erythroid-derived 2)-like 2, (Nrf2) signaling. Treatment with SnPP, a pharmacological inhibitor of HO-1, and knockdown of HO-1 with small interfering RNA (siRNA) restored caspase-3 activity suppressed by gAcrp, indicating a critical role of HO-1 in mediating the protective role of gAcrp in ethanol-induced apoptosis in liver cells. In addition, carbon monoxide, a byproduct obtained from the catabolism of free heme was found to contribute to the anti-apoptotic effect of adiponectin. In conclusion, these data demonstrated that globular adiponectin prevents ethanol-induced apoptosis in HepG2 cells via HO-1 induction and revealed a novel biological response of globular adiponectin in the protection of liver injury from alcohol consumption.

  8. Cathepsin inhibition-induced lysosomal dysfunction enhances pancreatic beta-cell apoptosis in high glucose.

    PubMed

    Jung, Minjeong; Lee, Jaemeun; Seo, Hye-Young; Lim, Ji Sun; Kim, Eun-Kyoung

    2015-01-01

    Autophagy is a lysosomal degradative pathway that plays an important role in maintaining cellular homeostasis. We previously showed that the inhibition of autophagy causes pancreatic β-cell apoptosis, suggesting that autophagy is a protective mechanism for the survival of pancreatic β-cells. The current study demonstrates that treatment with inhibitors and knockdown of the lysosomal cysteine proteases such as cathepsins B and L impair autophagy, enhancing the caspase-dependent apoptosis of INS-1 cells and islets upon exposure to high concentration of glucose. Interestingly, treatment with cathepsin B and L inhibitors prevented the proteolytic processing of cathepsins B, D and L, as evidenced by gradual accumulation of the respective pro-forms. Of note, inhibition of aspartic cathepsins had no effect on autophagy and cell viability, suggesting the selective role of cathepsins B and L in the regulation of β-cell autophagy and apoptosis. Lysosomal localization of accumulated pro-cathepsins in the presence of cathepsin B and L inhibitors was verified via immunocytochemistry and lysosomal fractionation. Lysotracker staining indicated that cathepsin B and L inhibitors led to the formation of severely enlarged lysosomes in a time-dependent manner. The abnormal accumulation of pro-cathepsins following treatment with inhibitors of cathepsins B and L suppressed normal lysosomal degradation and the processing of lysosomal enzymes, leading to lysosomal dysfunction. Collectively, our findings suggest that cathepsin defects following the inhibition of cathepsin B and L result in lysosomal dysfunction and consequent cell death in pancreatic β-cells.

  9. LPS inhibits caspase 3-dependent apoptosis in RAW264.7 macrophages induced by the AMPK activator AICAR

    SciTech Connect

    Russe, Otto Quintus Möser, Christine V. Kynast, Katharina L. King, Tanya S. Olbrich, Katrin Grösch, Sabine Geisslinger, Gerd Niederberger, Ellen

    2014-05-09

    Highlights: • AMPK-activation induces caspase 3-dependent apoptosis in macrophages. • Apoptosis is associated with decreased mTOR and increased p21 levels. • All effects can be significantly inhibited by the TLR4 agonist lipopolysaccharide. - Abstract: AMP-activated kinase is a cellular energy sensor which is activated in stages of increased ATP consumption. Its activation has been associated with a number of beneficial effects such as decreasing inflammatory processes and the disease progress of diabetes and obesity, respectively. Furthermore, AMPK activation has been linked with induction of cell cycle arrest and apoptosis in cancer and vascular cells, indicating that it might have a therapeutic impact for the treatment of cancer and atherosclerosis. However, the impact of AMPK on the proliferation of macrophages, which also play a key role in the formation of atherosclerotic plaques and in inflammatory processes, has not been focused so far. We have assessed the influence of AICAR- and metformin-induced AMPK activation on cell viability of macrophages with and without inflammatory stimulation, respectively. In cells without inflammatory stimulation, we found a strong induction of caspase 3-dependent apoptosis associated with decreased mTOR levels and increased expression of p21. Interestingly, these effects could be inhibited by co-stimulation with bacterial lipopolysaccharide (LPS) but not by other proinflammatory cytokines suggesting that AICAR induces apoptosis via AMPK in a TLR4-pathway dependent manner. In conclusion, our results revealed that AMPK activation is not only associated with positive effects but might also contribute to risk factors by disturbing important features of macrophages. The fact that LPS is able to restore AMPK-associated apoptosis might indicate an important role of TLR4 agonists in preventing unfavorable cell death of immune cells.

  10. Inhibiting ROS-STAT3-dependent autophagy enhanced capsaicin-induced apoptosis in human hepatocellular carcinoma cells.

    PubMed

    Chen, Xun; Tan, Miduo; Xie, Zhiqin; Feng, Bin; Zhao, Zhijian; Yang, Kaiqing; Hu, Chen; Liao, Ni; Wang, Taoli; Chen, Dongliang; Xie, Feng; Tang, Caixi

    2016-07-01

    Capsaicin, which is the pungent ingredient of red hot chili peppers, has been reported to possess anticancer activity, including that against hepatocellular carcinoma. However, the precise molecular mechanisms by which capsaicin exerts its anticancer effects remain poorly understood. Herein, we have tested the involvement of autophagy in the capsaicin mechanism of action in human hepatocellular carcinoma. HepG2 cancer cells were treated with different doses of capsaicin (50, 100 and 200μmol/L) for 6, 12, and 24 h. Flow cytometry and Caspase-3 activity assay were performed to determine cell apoptosis. Immunofluorescence was performed to visualize LC3-positive puncta. Western blotting was used to detect the expression of the hallmarks of apoptosis and autophagy. Capsaicin can induce apoptosis in HepG2 cells. The expression levels of CL-PARP and Bcl-2 were significantly increased. In line with the apoptosis, capsaicin can trigger autophagy in HepG2 cells. Capsaicin increased LC3-II and beclin-1 expression and GFP-LC3-positive autophagosomes. Pharmacological or genetic inhibition of autophagy further sensitized HepG2 cells to capsaicin-induced apoptosis. Mechanistically, capsaicin upregulated the Stat3 activity which contributed to autophagy. Importantly, we found that capsaicin triggered reactive oxygen species (ROS) generation in hepatoma cells and that the levels of ROS decreased with N-acetyl-cysteine (NAC), a ROS scavenger. Moreover, NAC abrogated the effects of capsaicin on Stat3-dependent autophagy. In this study, we demonstrated that capsaicin increased the phosphorylation of signal transducer and activator of transcription 3 (p-STAT3)-dependent autophagy through the generation of ROS signaling pathways in human hepatoma. Inhibiting autophagy could enhance capsaicin-induced apoptosis in human hepatocellular carcinoma.

  11. TRAF2 inhibits TRAIL- and CD95L-induced apoptosis and necroptosis.

    PubMed

    Karl, I; Jossberger-Werner, M; Schmidt, N; Horn, S; Goebeler, M; Leverkus, M; Wajant, H; Giner, T

    2014-10-09

    The relevance of the adaptor protein TNF receptor-associated factor 2 (TRAF2) for signal transduction of the death receptor tumour necrosis factor receptor1 (TNFR1) is well-established. The role of TRAF2 for signalling by CD95 and the TNF-related apoptosis inducing ligand (TRAIL) DRs, however, is only poorly understood. Here, we observed that knockdown (KD) of TRAF2 sensitised keratinocytes for TRAIL- and CD95L-induced apoptosis. Interestingly, while cell death was fully blocked by the pan-caspase inhibitor benzyloxycarbonyl-Val-Ala-Asp(OMe)-fluoromethylketone (zVAD-fmk) in control cells, TRAF2-depleted keratinocytes were only partly rescued from TRAIL- and CD95L-induced cell death. In line with the idea the only partially protective effect of zVAD-fmk on TRAIL- and CD95L-treated TRAF2-depleted keratinocytes is due to the induction of necroptosis, combined treatment with zVAD-fmk and the receptor interacting protein 1 (RIP1) inhibitor necrostatin-1 [corrected] fully rescued these cells. To better understand the impact of TRAF2 levels on RIP1- and RIP3-dependent necroptosis and RIP3-independent apoptosis, we performed experiments in HeLa cells that lack endogenous RIP3 and HeLa cells stably transfected with RIP3. HeLa cells, in which necroptosis has no role, were markedly sensitised to TRAIL-induced caspase-dependent apoptosis by TRAF2 KD. In RIP3-expressing HeLa transfectants, however, KD of TRAF2 also strongly sensitised for TRAIL-induced necroptosis. Noteworthy, priming of keratinocytes with soluble TWEAK, which depletes the cytosolic pool of TRAF2-containing protein complexes, resulted in strong sensitisation for TRAIL-induced necroptosis but had only a very limited effect on TRAIL-induced apoptosis. The necroptotic TRAIL response was not dependent on endogenously produced TNF and TNFR signalling, since blocking TNF by TNFR2-Fc or anti-TNFα had no effect on necroptosis induction. Taken together, we identified TRAF2 not only as a negative regulator of DR-induced

  12. Non-dioxin-like PCBs interact with benzo[a]pyrene-induced p53-responses and inhibit apoptosis

    SciTech Connect

    Al-Anati, Lauy Hoegberg, Johan; Stenius, Ulla

    2010-12-01

    Non-dioxin-like polychlorinated biphenyls (NDL-PCBs) and polycyclic aromatic hydrocarbons (PAHs) are ubiquitous pollutants often co-existing in contaminated environments. However, there are few studies on the effects of co-exposure, in particular on effects of pure NDL-PCB congeners and PAHs. We have evaluated the effects of some highly purified NDL-PCBs and benzo[a]pyrene (BP) on BP-induced Raf, Erk, Mdm2, p53 signaling and on BP-induced apoptosis and cell cycle arrest. PCBs (1 {mu}M) were added to HepG2 cells 1 h prior to BP and the incubation was stopped at 24 h. Employing Western blotting we found that NDL-PCBs (28, 101 and 153) amplified the BP-induced inactivating phosphorylation of Raf (pRaf Ser 259) and decreased levels of pErk Tyr 204. This treatment also resulted in the attenuation of BP-induced Mdm2 phosphorylation at Ser166 and amplification of the p53 Ser15 response. These effects were associated with an unexpected inhibition of BP-induced apoptosis. A dioxin-like PCB (DL-PCB 126) was used as reference and gave results that were predictable from previous studies, i.e. it attenuated BP-induced p53 response and apoptosis. In an effort to explain why the NDL-PCB-induced amplification of the p53 response was associated with a decreased apoptotic response we analyzed FoxO3a, which may translocate p53 to the cytoplasm. We found that NDL-PCBs reduced the level of phosphorylated FoxO3a at Thr32. This phosphorylation promotes a cytoplasmic translocation of FoxO3a and p53 and our data suggest that NDL-PCBs may inhibit BP-induced apoptosis by preventing a FoxO3a-dependent translocation of p53 to the cytoplasm.

  13. Flavanonol taxifolin attenuates proteasome inhibition-induced apoptosis in differentiated PC12 cells by suppressing cell death process.

    PubMed

    Nam, Yoon Jeong; Lee, Da Hee; Shin, Yong Kyoo; Sohn, Dong Suep; Lee, Chung Soo

    2015-03-01

    The proteasomal dysfunction and mitochondrial impairment has been implicated in neuronal degeneration. Taxifolin has antioxidant and anti-inflammatory effects. However, the effect of taxifolin on the neuronal cell death induced by proteasome inhibition has not been studied. Therefore, in the respect of cell death process, we assessed the effect of taxifolin on the proteasome inhibition-induced apoptosis in neuronal cell injury using differentiated PC12 cells. The proteasome inhibitors MG132 and MG115 induced a decrease in Bid, Bcl-2, and survivin protein levels, an increase in Bax, loss of the mitochondrial transmembrane potential, cytochrome c release, activation of caspases(-8, -9 and -3), an increase in the tumor suppressor p53 levels and cleavage of PARP-1. The addition of taxifolin attenuated the proteasome inhibitor-induced changes in the apoptosis-related protein levels, formation of reactive oxygen species, depletion and oxidation of GSH, formations of malondialdehyde and carbonyls, and cell death. The results show that taxifolin may attenuate the proteasome inhibitor-induced apoptosis in PC12 cells by suppressing the activation of the mitochondrial pathway and the caspase-8- and Bid-dependent pathways. The preventive effect of taxifolin appears to be attributed to its inhibitory effect on the formation of reactive oxygen species, and depletion and oxidation of GSH.

  14. Hsf-1 and POB1 induce drug sensitivity and apoptosis by inhibiting Ralbp1.

    PubMed

    Singhal, Sharad S; Yadav, Sushma; Drake, Kenneth; Singhal, Jyotsana; Awasthi, Sanjay

    2008-07-11

    Hsf-1 (heat shock factor-1) is a transcription factor that is known to regulate cellular heat shock response through its binding with the multispecific transporter protein, Ralbp1. Results of present studies demonstrate that Hsf-1 causes specific and saturable inhibition of the transport activity of Ralbp1 and that the combination of Hsf-1 and POB1 causes nearly complete inhibition through specific bindings with Ralbp1. Augmentation of cellular levels of Hsf-1 and POB1 caused dramatic apoptosis in non-small cell lung cancer cell line H358 through Ralbp1 inhibition. These findings indicate a novel model for mutual regulation of Hsf-1 and Ralbp1 through Ralbp1-mediated sequestration of Hsf-1 in the cellular cytoskeleton and Hsf-1-mediated inhibition of the transport activity of membrane-bound Ralbp1.

  15. Antibiotic drug levofloxacin inhibits proliferation and induces apoptosis of lung cancer cells through inducing mitochondrial dysfunction and oxidative damage.

    PubMed

    Song, Meijun; Wu, Hongcheng; Wu, Shibo; Ge, Ting; Wang, Guoan; Zhou, Yingyan; Sheng, Shimo; Jiang, Jingbo

    2016-12-01

    Lung cancer is the leading cause of cancer death worldwide and its clinical management remains challenge. Here, we repurposed antibiotic levofloxacin for lung cancer treatment. We show that levofloxacin is effectively against a panel of lung cancer cell lines via inhibiting proliferation and inducing apoptosis, regardless of cellular origin and genetic pattern, in in vitro cell culture system and in vivo xenograft lung tumor model. Mechanistically, levofloxacin inhibits activities of mitochondrial electron transport chain complex I and III, leading to inhibition of mitochondrial respiration and reduction of ATP production. In addition, levofloxacin significantly increases levels of ROS, mitochondrial superoxide and hydrogen peroxide in vitro and oxidative stress markers (HEL and 4-HNE) in vivo. Antioxidants, such as NAC and vitamin C, prevent the inhibitory effects of levofloxacin, confirming the induction of oxidative damage as the mechanism of its action in lung cancer cells. Our work demonstrates that levofloxacin is a useful addition to the treatment of lung cancer. Our work also suggests that targeting mitochondria may be an alternative therapeutic strategy for lung cancer treatment.

  16. Gallic Acid Inhibits Proliferation and Induces Apoptosis in Lymphoblastic Leukemia Cell Line (C121)

    PubMed Central

    Sourani, Zahra; Pourgheysari, Batoul; Beshkar, Pezhman; Shirzad, Hedayatollah; Shirzad, Moein

    2016-01-01

    Leukemia is known as the world’s fifth most prevalent cancer. New cytotoxic drugs have created considerable progress in the treatment, but side effects are still the important cause of mortality. Plant derivatives have been recently considered as important sources for the treatment of various diseases, including cancer. Gallic acid (GA) is a polyhydroxyphenolic compound with a wide range of biological functions. The aim of the present study was to evaluate the effect of GA on proliferation inhibition and apoptosis induction of a lymphoblastic leukemia cell line. Jurkat cell (C121) line was cultured in RPMI 1640 supplemented with 10% heat-inactivated fetal bovine serum (FBS) with different concentrations of GA (10, 20, 30, 40, 50, 60, 70, 80, 90, and 100 μM) for 24, 48 and 72 hours. The effect of GA on cell viability was measured using MTS assay. Induction of apoptosis was evaluated with Annexin V-FITC/PI kit and flow cytometry. Data were analyzed by SPSS version 20 using Kruskal-Wallis and Dunn’s multiple comparison tests. Decline of cell viability to less than 50% was observed at 60.3±1.6, 50.9±1.5, and 30.9±2.8 μM concentration after 24, 48, and 72 hours incubation, respectively. All concentrations of GA (10, 30, 50 and 80 μM) enhanced apoptosis compared to the control (P<0.05). The results demonstrate that the polyphenolic compound, GA, is effective in inhibition of proliferation and induction of apoptosis in Jurkat cell line. It is recommended to study the mechanism of apoptosis induction in future investigations. PMID:27853333

  17. A transcribed ultraconserved noncoding RNA, Uc.173, is a key molecule for the inhibition of lead-induced neuronal apoptosis.

    PubMed

    Nan, Aruo; Zhou, Xinke; Chen, Lijian; Liu, Meiling; Zhang, Nan; Zhang, Li; Luo, Yuanwei; Liu, Zhenzhong; Dai, Lijun; Jiang, Yiguo

    2016-01-05

    As a common toxic metal, lead has significant neurotoxicity to brain development. Long non-coding RNAs (lncRNAs) function in multiple biological processes. However, whether lncRNAs are involved in lead-induced neurotoxicity remains unclear. Uc.173 is a lncRNA from a transcribed ultra-conservative region (T-UCR) of human, mouse and rat genomes. We established a lead-induced nerve injury mouse model. It showed the levels of Uc.173 decreased significantly in hippocampus tissue and serum of the model. We further tested the expression of Uc.173 in serum of lead-exposed children, which also showed a tendency to decrease. To explore the effects of Uc.173 on lead-induced nerve injury, we overexpressed Uc.173 in an N2a mouse nerve cell line and found Uc.173 had an inhibitory effect on lead-induced apoptosis of N2a. To investigate the molecular mechanisms of Uc.173 in apoptosis associated with lead-induced nerve injury, we predicted the target microRNAs of Uc.173 by using miRanda, TargetScan and RegRNA. After performing quantitative real-time PCR and bioinformatics analysis, we showed Uc.173 might inter-regulate with miR-291a-3p in lead-induced apoptosis and regulate apoptosis-associated genes. Our study suggests Uc.173 significantly inhibits the apoptosis of nerve cells, which may be mediated by inter-regulation with miRNAs in lead-induced nerve injury.

  18. Inhibition of Drp1 protects against senecionine-induced mitochondria-mediated apoptosis in primary hepatocytes and in mice.

    PubMed

    Yang, Xiao; Wang, Hua; Ni, Hong-Min; Xiong, Aizhen; Wang, Zhengtao; Sesaki, Hiromi; Ding, Wen-Xing; Yang, Li

    2017-03-02

    Pyrrolizidine alkaloids (PAs) are a group of compounds found in various plants and some of them are widely consumed in the world as herbal medicines and food supplements. PAs are potent hepatotoxins that cause irreversible liver injury in animals and humans. However, the mechanisms by which PAs induce liver injury are not clear. In the present study, we determined the hepatotoxicity and molecular mechanisms of senecionine, one of the most common toxic PAs, in primary cultured mouse and human hepatocytes as well as in mice. We found that senecionine administration increased serum alanine aminotransferase levels in mice. H&E and TUNEL staining of liver tissues revealed increased hemorrhage and hepatocyte apoptosis in liver zone 2 areas. Mechanistically, senecionine induced loss of mitochondrial membrane potential, release of mitochondrial cytochrome c as well as mitochondrial JNK translocation and activation prior to the increased DNA fragmentation and caspase-3 activation in primary cultured mouse and human hepatocytes. SP600125, a specific JNK inhibitor, and ZVAD-fmk, a general caspase inhibitor, alleviated senecionine-induced apoptosis in primary hepatocytes. Interestingly, senecionine also caused marked mitochondria fragmentation in hepatocytes. Pharmacological inhibition of dynamin-related protein1 (Drp1), a protein that is critical to regulate mitochondrial fission, blocked senecionine-induced mitochondrial fragmentation and mitochondrial release of cytochrome c and apoptosis. More importantly, hepatocyte-specific Drp1 knockout mice were resistant to senecionine-induced liver injury due to decreased mitochondrial damage and apoptosis. In conclusion, our results uncovered a novel mechanism of Drp1-mediated mitochondrial fragmentation in senecionine-induced liver injury. Targeting Drp1-mediated mitochondrial fragmentation and apoptosis may be a potential avenue to prevent and treat hepatotoxicity induced by PAs.

  19. The potassium ion channel opener NS1619 inhibits proliferation and induces apoptosis in A2780 ovarian cancer cells

    SciTech Connect

    Han Xiaobing; Xi Ling; Wang Hui; Huang Xiaoyuan; Ma Xiangyi; Han Zhiqiang; Wu Peng; Ma Xiaoli; Lu Yunping; Wang, Gang Zhou Jianfeng; Ma Ding

    2008-10-17

    Diverse types of voltage-gated potassium (K{sup +}) channels have been shown to be involved in regulation of cell proliferation. The maxi-conductance Ca{sup 2+}-activated K{sup +} channels (BK channels) may play an important role in the progression of human cancer. To explore the role of BK channels in regulation of apoptosis in human ovarian cancer cells, the effects of the specific BK channel activator NS1619 on induction of apoptosis in A2780 cells were observed. Following treatment with NS1619, cell proliferation was measured by MTT assay. Apoptosis of A2780 cells pretreated with NS1619 was detected by agarose gel electrophoresis of cellular DNA and flow cytometry. Our data demonstrate that NS1619 inhibits the proliferation of A2780 cells in a dosage and time dependent manner IC{sub 50} = 31.1 {mu}M, for 48 h pretreatment and induces apoptosis. Western blot analyses showed that the anti-proliferation effect of NS1619 was associated with increased expression of p53, p21, and Bax. These results indicate that BK channels play an important role in regulating proliferation of human ovarian cancer cells and may induce apoptosis through induction of p21{sup Cip1} expression in a p53-dependent manner.

  20. Inhibition of P-glycoprotein by wogonin is involved with the potentiation of etoposide-induced apoptosis in cancer cells.

    PubMed

    Lee, Eibai; Enomoto, Riyo; Koshiba, Chika; Hirano, Hiroyuki

    2009-08-01

    Etoposide induces apoptotic cell death in normal and cancer cells. This apoptosis plays a role not only in anticancer effects but also in adverse reactions, such as myelosuppression. Because we had previously found that wogonin, a flavone found in a plant, suppresses thymocyte apoptosis induced by etoposide, we examined the effect of this flavone in cancer cells. Wogonin significantly potentiated etoposide-induced apoptosis in HL-60 cells. This flavone impaired the function of P-glycoprotein and then increased cellular content of etoposide in the cells. Thus, this flavone is likely to act as an inhibitor of P-glycoprotein and potentiate the apoptotic action of etoposide. On the other hand, wogonin inhibited etoposide-induced apoptosis in thymocytes, one of the normal cells. The potentiation by wogonin is likely to be a specific action for cancer cells but not normal cells. Therefore, this flavone may be used to reduce the excretion of the anticancer agents via P-glycoprotein and increase the pharmacological action of it in cancer cells. These results suggest that wogonin may play a role in overcoming multidrug resistance.

  1. Free radical scavenger edaravone suppresses x-ray-induced apoptosis through p53 inhibition in MOLT-4 cells.

    PubMed

    Sasano, Nakashi; Enomoto, Atsushi; Hosoi, Yoshio; Katsumura, Yosuke; Matsumoto, Yoshihisa; Shiraishi, Kenshiro; Miyagawa, Kiyoshi; Igaki, Hiroshi; Nakagawa, Keiichi

    2007-11-01

    Edaravone, a clinical drug used widely for the treatment of acute cerebral infarction, is reported to scavenge free radicals. In the present study, we investigated the radioprotective effect of edaravone on X-ray-induced apoptosis in MOLT-4 cells. Apoptosis was determined by the dye exclusion test, Annexin V binding assay, cleavage of caspase, and DNA fragmentation. We found that edaravone significantly suppressed the X-ray-induced apoptosis. The amount of intracellular ROS production was determined by the chloromethyl-2',7'-dichlorodihydro-fluorescein diacetate system. We found that the intracellular ROS production by X-irradiation was completely suppressed by the addition of edaravone. The accumulation and phosphorylation of p53 and the expression of p21(WAF1), a target protein of p53, which were induced by X-irradiation, were also suppressed by adding edaravone. We conclude that the free radical scavenger edaravone suppresses X-ray-induced apoptosis in MOLT-4 cells by inhibiting p53.

  2. Inhibition of Cathepsin B by E-64 Induces Oxidative Stress and Apoptosis in Filarial Parasite

    PubMed Central

    Wadhawan, Mohit; Singh, Neetu; Rathaur, Sushma

    2014-01-01

    Background Current available antifilarial drug strategies only eliminate the larval stages of filarial parasites. Therefore, there is an urgent need of drugs which are macrofilaricidals. Identification of molecular targets crucial for survival of parasite is a prerequisite for drug designing. Cathepsin B, a cysteine protease family member is known to play crucial role in the normal growth, digestion of nutrients, exsheathment of the helminth parasites. Therefore, we targeted this enzyme in the filarial parasite using its specific inhibitor, E-64. Methods and Findings We have exposed the parasites to E-64 and observed their motility and viability at various time intervals. It caused marked decrease in the motility and viability of the parasites ultimately leading to their death after 8 hours. It is well known that E-64 protects the cell from apoptosis, however, it causes apoptotic effect in carcinoma cell lines. To understand the mechanism of action of E-64 on parasite survival, we have measured levels of different apoptotic markers in the treated parasites. E-64 significantly reduced the level of ced-9 and activity of tyrosine phosphatases, cytochrome c oxidase. It also activated ced-3, homolog of mammalian caspase 3 suggesting initiation of an apoptotic like event in the filarial parasites. Different antioxidant enzymes were also evaluated to further explore the mechanism behind the death of the parasites. There was marked decrease in the level of GSH and activity of Glutathione reductase and glutathione-s-transferase leading to increased generation of reactive oxygen species. This led to the induced oxidation of fatty acids and protein which might alter the mitochondrial membrane permeability. Conclusion This study suggests that inhibition of cathepsin B by E-64 generates oxidative stress followed by mitochondrial mediated apoptotic like event in filarial parasites leading to their death. Hence, suggesting filarial cathepsin B as a potential chemotherapeutic

  3. Gracilaria edulis extract induces apoptosis and inhibits tumor in Ehrlich Ascites tumor cells in vivo

    PubMed Central

    2013-01-01

    Background Marine environment is inestimable for their chemical and biological diversity and therefore is an extraordinary resource for the discovery of new anticancer drugs. Recent development in elucidation of the mechanism and therapeutic action of natural products helped to evaluate for their potential activity. Methods We evaluated Gracilaria edulis J. Ag (Brown algae), for its antitumor potential against the Ehrlich ascites tumor (EAT) in vivo and in vitro. Cytotoxicity evaluation of Ethanol Extract of Gracilaria edulis (EEGE) using EAT cells showed significant activity. In vitro studies indicated that EEGE cytotoxicity to EAT cells is mediated through its ability to produce reactive oxygen species (ROS) and therefore decreasing intracellular glutathione (GSH) levels may be attributed to oxidative stress. Results Apoptotic parameters including Annexin-V positive cells, increased levels of DNA fragmentation and increased caspase-2, caspase-3 and caspase-9 activities indicated the mechanism might be by inducing apoptosis. Intraperitoneally administration of EEGE to EAT-bearing mice helped to increase the lifespan of the animals significantly inhibited tumor growth and increased survival of mice. Extensive hematology, biochemistry and histopathological analysis of liver and kidney indicated that daily doses of EEGE up to 300 mg/kg for 35 days are well tolerated and did not cause hematotoxicity nor renal or hepatotoxicity. Conclusion Comprehensive antitumor analysis in animal model and in Ehrlich Ascites Tumor cells was done including biochemical, and pathological evaluations indicate antitumor activity of the extract and non toxic in vivo. It was evident that the mechanism explains the apoptotic activity of the algae extract. PMID:24274337

  4. Inhibition of SIRT1 by a small molecule induces apoptosis in breast cancer cells

    SciTech Connect

    Kalle, Arunasree M.; Mallika, A.; Badiger, Jayasree; Alinakhi; Talukdar, Pinaki; Sachchidanand

    2010-10-08

    Research highlights: {yields} Novel small molecule SIRT1 inhibitor better than sirtinol. {yields} IC{sub 50} 500 nM. {yields} Specific tumor cytotoxicity towards breast cancer cells. {yields} Restoration of H3K9 acetylation levels to baseline when co-treated with SIRT1 activator (Activator X) and inhibitor (ILS-JGB-1741). -- Abstract: Overexpression of SIRT1, a NAD{sup +}-dependent class III histone deacetylases (HDACs), is implicated in many cancers and therefore could become a promising antitumor target. Here we demonstrate a small molecule SIRT1 inhibitor, ILS-JGB-1741(JGB1741) with potent inhibitory effects on the proliferation of human metastatic breast cancer cells, MDA-MB 231. The molecule has been designed using medicinal chemistry approach based on known SIRT1 inhibitor, sirtinol. The molecule showed a significant inhibition of SIRT1 activity compared to sirtinol. Studies on the antitumor effects of JGB on three different cancer cell lines, K562, HepG2 and MDA-MB 231 showed an IC{sub 50} of 1, 10 and 0.5 {mu}M, respectively. Further studies on MDA-MB 231 cells showed a dose-dependent increase in K9 and K382 acetylation of H3 and p53, respectively. Results also demonstrated that JGB1741-induced apoptosis is associated with increase in cytochrome c release, modulation in Bax/Bcl2 ratio and cleavage of PARP. Flowcytometric analysis showed increased percentage of apoptotic cells, decrease in mitochondrial membrane potential and increase in multicaspase activation. In conclusion, the present study indicates the potent apoptotic effects of JGB1741 in MDA-MB 231 cells.

  5. Inhibition of N-methyl-D-aspartate receptors increases paraoxon-induced apoptosis in cultured neurons

    SciTech Connect

    Wu Xuan; Tian Feng; Okagaki, Peter; Marini, Ann M. . E-mail: amarini@usuhs.mil

    2005-10-01

    Organophosphorus (OP) compounds, used as insecticides and chemical warfare agents, are potent neurotoxins. We examined the neurotoxic effect of paraoxon (O,O-diethyl O-p-nitrophenyl phosphate), an organophosphate compound, and the role of NMDA receptors as a mechanism of action in cultured cerebellar granule cells. Paraoxon is neurotoxic to cultured rat cerebellar granule cells in a time- and concentration-dependent manner. Cerebellar granule cells are less sensitive to the neurotoxic effects of paraoxon on day in vitro (DIV) 4 than neurons treated on DIV 8. Surprisingly, the N-methyl-D-aspartate (NMDA) receptor antagonist, MK-801, enhances paraoxon-mediated neurotoxicity suggesting that NMDA receptors may play a protective role. Pretreatment with a subtoxic concentration of N-methyl-D-aspartate (NMDA) [100 {mu}M] protects about 40% of the vulnerable neurons that would otherwise die from paraoxon-induced neurotoxicity. Moreover, addition of a neuroprotective concentration of NMDA 3 h after treatment with paraoxon provides the same level of protection. Because paraoxon-mediated neuronal cell death is time-dependent, we hypothesized that apoptosis may be involved. Paraoxon increases apoptosis about 10-fold compared to basal levels. The broad-spectrum caspase inhibitor (Boc-D-FMK) and the caspase-9-specific inhibitor (Z-LEHD-FMK) protect against paraoxon-mediated apoptosis, paraoxon-stimulated caspase-3 activity and neuronal cell death. MK-801 increases, whereas NMDA blocks paraoxon-induced apoptosis and paraoxon-stimulated caspase-3 activity. These results suggest that activation of NMDA receptors protect neurons against paraoxon-induced neurotoxicity by blocking apoptosis initiated by paraoxon.

  6. Cyclooxygenase-2 over-expression inhibits liver apoptosis induced by hyperglycemia.

    PubMed

    Francés, Daniel E A; Ingaramo, Paola I; Mayoral, Rafael; Través, Paqui; Casado, Marta; Valverde, Ángela M; Martín-Sanz, Paloma; Carnovale, Cristina E

    2013-03-01

    Increased expression of COX-2 has been linked to inflammation and carcinogenesis. Constitutive expression of COX-2 protects hepatocytes from several pro-apoptotic stimuli. Increased hepatic apoptosis has been observed in experimental models of diabetes. Our present aim was to analyze the role of COX-2 as a regulator of apoptosis in diabetic mouse liver. Mice of C57BL/6 strain wild type (Wt) and transgenic in COX-2 (hCOX-2 Tg) were separated into Control (vehicle) and SID (streptozotocin induced diabetes, 200 mg/kg body weight, i.p.). Seven days post-injection, Wt diabetic animals showed a decrease in PI3K activity and P-Akt levels, an increase of P-JNK, P-p38, pro-apoptotic Bad and Bax, release of cytochrome c and activities of caspases-3 and -9, leading to an increased apoptotic index. This situation was improved in diabetic COX-2 Tg. In addition, SID COX-2 Tg showed increased expression of anti-apoptotic Mcl-1 and XIAP. Pro-apoptotic state in the liver of diabetic animals was improved by over-expression of COX-2. We also analyzed the roles of high glucose-induced apoptosis and hCOX-2 in vitro. Non-transfected and hCOX-2-transfected cells were cultured at 5 and 25 mM of glucose by 72 h. At 25 mM there was an increase in apoptosis in non-transfected cells versus those exposed to 5 mM. This increase was partly prevented in transfected cells at 25 mM. Moreover, the protective effect observed in hCOX-2-transfected cells was suppressed by addition of DFU (COX-2 selective inhibitor), and mimicked by addition of PGE(2) in non-transfected cells. Taken together, these results demonstrate that hyperglycemia-induced hepatic apoptosis is protected by hCOX-2 expression.

  7. Chitosan attenuates dibutyltin-induced apoptosis in PC12 cells through inhibition of the mitochondria-dependent pathway.

    PubMed

    Wang, Xiaorui; Miao, Junqiu; Yan, Chaoqun; Ge, Rui; Liang, Taigang; Liu, Enli; Li, Qingshan

    2016-10-20

    Dibutyltin (DBT) which was widely used as biocide and plastic stabilizer has been described as a potent neurotoxicant. Chitosan (CS), a natural nontoxic biopolymer, possesses a variety of biological activities including antibacterial, antifungal, free radical scavenging and neuroprotective activities. The present study was undertaken to investigate the protective effects of CS against DBT-induced apoptosis in rat pheochromocytoma (PC12) cells and the underlying mechanisms in vitro. Our results demonstrated that pretreatment with CS significantly increased the cell viability and decreased lactate dehydrogenase (LDH) release induced by DBT in a dose-dependent manner. Meanwhile, DBT-induced cell apoptosis, mitochondrial membrane potential (MMP) disruption, and generation of intracellular reactive oxygen species (ROS) were attenuated by CS. Real-time PCR assay showed that DBT markedly enhanced the mRNA levels of Bax, Bad, cytochrome-c and Apaf-1, reduced the Bcl-2 and Bcl-xL mRNA levels, while these genes expression alteration could be partially reversed by CS treatment. Furthermore, CS also inhibited the DBT-inducted activation of caspase-9, and -3 at mRNA and protein expression levels. Taken together, these results suggested that CS could protect the PC12 cells from apoptosis induced by DBT through inhibition of the mitochondria-dependent pathway.

  8. Apoptosis of Corneal Epithelial Cells Caused by Ultraviolet B-induced Loss of K(+) is Inhibited by Ba(2.).

    PubMed

    Glupker, Courtney D; Boersma, Peter M; Schotanus, Mark P; Haarsma, Loren D; Ubels, John L

    2016-07-01

    UVB exposure at ambient outdoor levels triggers rapid K(+) loss and apoptosis in human corneal limbal epithelial (HCLE) cells cultured in medium containing 5.5 mM K(+), but considerably less apoptosis occurs when the medium contains the high K(+) concentration that is present in tears (25 mM). Since Ba(2+) blocks several K(+) channels, we tested whether Ba(2+)-sensitive K(+) channels are responsible for some or all of the UVB-activated K(+) loss and subsequent activation of the caspase cascade and apoptosis. Corneal epithelial cells in culture were exposed to UVB at 80 or 150 mJ/cm(2). Patch-clamp recording was used to measure UVB-induced K(+) currents. Caspase-activity and TUNEL assays were performed on HCLE cells exposed to UVB followed by incubation in the presence or absence of Ba(2+). K(+) currents were activated in HCLE cells following UVB-exposure. These currents were reversibly blocked by 5 mM Ba(2+). When HCLE cells were incubated with 5 mM Ba(2+) after exposure to UVB, activation of caspases-9, -8, and -3 and DNA fragmentation were significantly decreased. The data confirm that UVB-induced K(+) current activation and loss of intracellular K(+) leads to activation of the caspase cascade and apoptosis. Extracellular Ba(2+) inhibits UVB-induced apoptosis by preventing loss of intracellular K(+) when K(+) channels are activated. Ba(2+) therefore has effects similar to elevated extracellular K(+) in protecting HCLE cells from UVB-induced apoptosis. This supports our overall hypothesis that elevated K(+) in tears contributes to protection of the corneal epithelium from adverse effects of ambient outdoor UVB.

  9. L-carnitine attenuates H2O2-induced neuron apoptosis via inhibition of endoplasmic reticulum stress.

    PubMed

    Ye, Junli; Han, Yantao; Chen, Xuehong; Xie, Jing; Liu, Xiaojin; Qiao, Shunhong; Wang, Chunbo

    2014-12-01

    Both oxidative stress and endoplasmic reticulum stress (ER stress) have been linked to pathogenesis of neurodegenerative diseases. Our previous study has shown that L-carnitine may function as an antioxidant to inhibit H2O2-induced oxidative stress in neuroblastoma SH-SY5Y cells. To further explore the neuroprotection of L-carnitine, here we study the effects of L-carnitine on the ER stress response in H2O2-induced SH-SY5Y cell injury. Our results showed that L-carnitine pretreatment could increase cell viability; inhibit apoptosis and ROS accumulation caused by H2O2 or tunicamycin (TM). L-carnitine suppress the endoplasmic reticulum dilation and activation of ER stress-associated proteins including glucose-regulated protein 78 (GRP78), CCAAT/enhancer-binding protein-homologous protein (CHOP), JNK, Bax and Bim induced by H2O2 or TM. In addition, H2O2-induced cell apoptosis and activation of ER stress can also be attenuated by antioxidant N-acetylcysteine (NAC), CHOP siRNA and the inhibitor of ER stress 4-phenylbutyric acid (4-PBA). Taken together, our results demonstrated that H2O2 could trigger both oxidative stress and ER stress in SH-SY5Y cells, and ER stress participated in SH-SY5Y apoptosis mediated by H2O2-induced oxidative stress. CHOP/Bim or JNK/Bim-dependent ER stress signaling pathways maybe related to the neuroprotective effects of L-carnitine against H2O2-induced apoptosis and oxidative injury.

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

    PubMed

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

    2013-09-01

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

  11. Glibenclamide induces apoptosis through inhibition of cystic fibrosis transmembrane conductance regulator (CFTR) Cl(-) channels and intracellular Ca(2+) release in HepG2 human hepatoblastoma cells.

    PubMed

    Kim, J A; Kang, Y S; Lee, S H; Lee, E H; Yoo, B H; Lee, Y S

    1999-08-11

    Glibenclamide, an inhibitor of cystic fibrosis transmembrane conductance regulator (CFTR) Cl(-) channels, induced apoptosis in a dose- and time-dependent manner in HepG2 human hepatoblastoma cells. Glibenclamide increased intracellular Ca(2+) concentration, which was significantly inhibited by Ca(2+) release blockers dantrolene and TMB-8. BAPTA/AM, an intracellular Ca(2+) chelator, and the Ca(2+) release blockers significantly inhibited glibenclamide-induced apoptosis. Glibanclamide also increased intracellular Cl(-) concentration, which was significantly blocked by CFTR Cl(-) channel activators levamisole and bromotetramisole. These activators also significantly inhibited both intracellular Ca(2+) release and apoptosis induced by glibenclamide. The expression of CFTR protein in the cells was confirmed by Western blot analysis. These results suggest that glibenclamide induced apoptosis through inhibition of CFTR Cl(-) channels and intracellular Ca(2+) release and that this protein may be a good target for treatment of human hepatomas.

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

    SciTech Connect

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

    2014-04-18

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

  13. Pachymic Acid Inhibits Growth and Induces Apoptosis of Pancreatic Cancer In Vitro and In Vivo by Targeting ER Stress

    PubMed Central

    Cheng, Shujie; Swanson, Kristen; Eliaz, Isaac; McClintick, Jeanette N.; Sandusky, George E.; Sliva, Daniel

    2015-01-01

    Pachymic acid (PA) is a purified triterpene extracted from medicinal fungus Poria cocos. In this paper, we investigated the anticancer effect of PA on human chemotherapy resistant pancreatic cancer. PA triggered apoptosis in gemcitabine-resistant pancreatic cancer cells PANC-1 and MIA PaCa-2. Comparative gene expression array analysis demonstrated that endoplasmic reticulum (ER) stress was induced by PA through activation of heat shock response and unfolded protein response related genes. Induced ER stress was confirmed by increasing expression of XBP-1s, ATF4, Hsp70, CHOP and phospho-eIF2α. Moreover, ER stress inhibitor tauroursodeoxycholic acid (TUDCA) blocked PA induced apoptosis. In addition, 25 mg kg-1 of PA significantly suppressed MIA PaCa-2 tumor growth in vivo without toxicity, which correlated with induction of apoptosis and expression of ER stress related proteins in tumor tissues. Taken together, growth inhibition and induction of apoptosis by PA in gemcitabine-resistant pancreatic cancer cells were associated with ER stress activation both in vitro and in vivo. PA may be potentially exploited for the use in treatment of chemotherapy resistant pancreatic cancer. PMID:25915041

  14. MicroRNA-221/222 regulate ox-LDL-induced endothelial apoptosis via Ets-1/p21 inhibition.

    PubMed

    Qin, Bing; Cao, Yuze; Yang, Huan; Xiao, Bo; Lu, Zhengqi

    2015-07-01

    Endothelial cells (ECs) apoptosis induced by oxidized low-density lipoprotein (ox-LDL) is thought to play an essential role in atherosclerosis. MicroRNAs (miRNAs) are a class of short non-coding RNAs, acting as posttranscriptional regulators of protein-coding genes involved in vascular cell biology. MiRNA-221 and miRNA-222 (miR-221/222) are known to be involved in the regulation of endothelial inflammation and angiogenesis. However, the function of miR-221/222 in ox-LDL-induced ECs apoptosis and atherosclerosis is still unknown. Here, we showed that miR-221/222 expression was markedly down-regulated in ox-LDL-induced apoptotic human umbilical cord vein endothelial cells. MiR-221/222 inhibition enhanced apoptosis in ECs, whereas over-expression of miR-221/222 could partly alleviate apoptotic cell death mediated by ox-LDL through suppression of Ets-1 and its downstream target p21. These findings suggest that manipulation of the miR-221/222-Ets-1-p21 pathway may offer a novel strategy for treatment of endothelial apoptosis and atherosclerosis.

  15. Salinomycin inhibits proliferation and induces apoptosis of human nasopharyngeal carcinoma cell in vitro and suppresses tumor growth in vivo.

    PubMed

    Wu, Danxin; Zhang, Yu; Huang, Jie; Fan, Zirong; Shi, Fengrong; Wang, Senming

    2014-01-10

    Salinomycin (Sal) is a polyether ionophore antibiotic that has recently been shown to induce cell death in various human cancer cells. However, whether salinomycin plays a functional role in nasopharyngeal carcinoma (NPC) has not been determined to date. The present study investigated the chemotherapeutic efficacy of salinomycin and its molecular mechanisms of action in NPC cells. Salinomycin efficiently inhibited proliferation and invasion of 3 NPC cell lines (CNE-1, CNE-2, and CNE-2/DDP) and activated a extensive apoptotic process that is accompanied by activation of caspase-3 and caspase-9, and decreased mitochondrial membrane potential. Meanwhile, the protein expression level of the Wnt coreceptor lipoprotein receptor related protein 6 (LRP6) and β-catenin was down-regulated, which showed that the Wnt/β-catenin signaling was involved in salinomycin-induced apoptosis of NPC cells. In a nude mouse NPC xenograft model, the anti-tumor effect of salinomycin was associated with the downregulation of β-catenin expression. The present study demonstrated that salinomycin can effectively inhibit proliferation and invasion, and induce apoptosis of NPC cells in vitro and inhibit tumor growth in vivo, probably via the inhibition of Wnt/β-catenin signaling, suggesting salinomycin as a potential candidate for the chemotherapy of NPC.

  16. Methyl Sartortuoate Inhibits Colon Cancer Cell Growth by Inducing Apoptosis and G2/M-Phase Arrest.

    PubMed

    Lan, Qiusheng; Li, Shoufeng; Lai, Wei; Xu, Heyang; Zhang, Yang; Zeng, Yujie; Lan, Wenjian; Chu, Zhonghua

    2015-08-17

    The potential anti-neoplastic activity of terpenoids is of continued interest. In this study, we investigate whether methyl sartortuoate, a terpenoid isolated from soft coral, induced cell cycle arrest and apoptosis in a human colon cancer cell line. Culture studies found that methyl sartortuoate inhibited colon cancer cell (LoVo and RKO) growth and caused apoptotic death in a concentration- and time-dependent manner, by activation of caspase-8, caspase-9, caspase-3, p53 and Bax, and inactivation of B-cell lymphoma 2 (Bcl-2) apoptosis regulating proteins. Methyl sartortuoate treatment led to reduced expression of cdc2 and up-regulated p21 and p53, suggesting that Methyl sartortuoate induced G2-M arrest through modulation of p53/p21/cdc2 pathways. Methyl sartortuoate also up-regulated phospho-JNK and phospho-p38 expression levels. This resulted in cell cycle arrest at the G2-M phase and apoptosis in LoVo and RKO cells. Treatment with the JNK inhibitor SP600125 and the p38 MAPK inhibitor SB203580 prevented methyl sartortuoate-induced apoptosis in LoVo cells. Moreover, methyl sartortuoate also prevented neoplasm growth in NOD-SCID nude mice inoculated with LoVo cells. Taken together, these findings suggest that methyl sartortuoate is capable of leading to activation of caspase-8, -9, -3, increasing p53 and Bax/Bcl-2 ratio apoptosis through MAPK-dependent apoptosis and results in G2-M phase arrest in LoVo and RKO cells. Thus, methyl sartortuoate may be a promising anticancer candidate.

  17. 6-Bromoindirubin-3'-oxime inhibits JAK/STAT3 signaling and induces apoptosis of human melanoma cells.

    PubMed

    Liu, Lucy; Nam, Sangkil; Tian, Yan; Yang, Fan; Wu, Jun; Wang, Yan; Scuto, Anna; Polychronopoulos, Panos; Magiatis, Prokopios; Skaltsounis, Leandros; Jove, Richard

    2011-06-01

    STAT3 is persistently activated and contributes to malignant progression in various cancers. Janus activated kinases (JAK) phosphorylate STAT3 in response to stimulation by cytokines or growth factors. The STAT3 signaling pathway has been validated as a promising target for development of anticancer therapeutics. Small-molecule inhibitors of JAK/STAT3 signaling represent potential molecular-targeted cancer therapeutic agents. In this study, we investigated the role of JAK/STAT3 signaling in 6-bromoindirubin-3'-oxime (6BIO)-mediated growth inhibition of human melanoma cells and assessed 6BIO as a potential anticancer drug candidate. We found that 6BIO is a pan-JAK inhibitor that induces apoptosis of human melanoma cells. 6BIO directly inhibited JAK-family kinase activity, both in vitro and in cancer cells. Apoptosis of human melanoma cells induced by 6BIO was associated with reduced phosphorylation of JAKs and STAT3 in both dose- and time-dependent manners. Consistent with inhibition of STAT3 signaling, expression of the antiapoptotic protein Mcl-1 was downregulated. In contrast to the decreased levels of phosphorylation of JAKs and STAT3, phosphorylation levels of the Akt and mitogen-activated protein kinase (MAPK) signaling proteins were not inhibited in cells treated with 6BIO. Importantly, 6BIO suppressed tumor growth in vivo with low toxicity in a mouse xenograft model of melanoma. Taken together, these results show that 6BIO is a novel pan-JAK inhibitor that can selectively inhibit STAT3 signaling and induces tumor cell apoptosis. Our findings support further development of 6BIO as a potential anticancer therapeutic agent that targets JAK/STAT3 signaling in tumor cells.

  18. Fluid shear stress inhibits TNF-alpha-induced apoptosis in osteoblasts: a role for fluid shear stress-induced activation of PI3-kinase and inhibition of caspase-3

    NASA Technical Reports Server (NTRS)

    Pavalko, Fredrick M.; Gerard, Rita L.; Ponik, Suzanne M.; Gallagher, Patricia J.; Jin, Yijun; Norvell, Suzanne M.

    2003-01-01

    In bone, a large proportion of osteoblasts, the cells responsible for deposition of new bone, normally undergo programmed cell death (apoptosis). Because mechanical loading of bone increases the rate of new bone formation, we hypothesized that mechanical stimulation of osteoblasts might increase their survival. To test this hypothesis, we investigated the effects of fluid shear stress (FSS) on osteoblast apoptosis using three osteoblast cell types: primary rat calvarial osteoblasts (RCOB), MC3T3-E1 osteoblastic cells, and UMR106 osteosarcoma cells. Cells were treated with TNF-alpha in the presence of cyclohexamide (CHX) to rapidly induce apoptosis. Osteoblasts showed significant signs of apoptosis within 4-6 h of exposure to TNF-alpha and CHX, and application of FSS (12 dyne/cm(2)) significantly attenuated this TNF-alpha-induced apoptosis. FSS activated PI3-kinase signaling, induced phosphorylation of Akt, and inhibited TNF-alpha-induced activation of caspase-3. Inhibition of PI3-kinase, using LY294002, blocked the ability of FSS to rescue osteoblasts from TNF-alpha-induced apoptosis and blocked FSS-induced inhibition of caspase-3 activation in osteoblasts treated with TNF-alpha. LY294002 did not, however, prevent FSS-induced phosphorylation of Akt suggesting that activation of Akt alone is not sufficient to rescue cells from apoptosis. This result also suggests that FSS can activate Akt via a PI3-kinase-independent pathway. These studies demonstrate for the first time that application of FSS to osteoblasts in vitro results in inhibition of TNF-alpha-induced apoptosis through a mechanism involving activation of PI3-kinase signaling and inhibition of caspases. FSS-induced activation of PI3-kinase may promote cell survival through a mechanism that is distinct from the Akt-mediated survival pathway. Copyright 2002 Wiley-Liss, Inc.

  19. p53-dependent NDRG1 expression induces inhibition of intestinal epithelial cell proliferation but not apoptosis after polyamine depletion.

    PubMed

    Zhang, Ai-Hong; Rao, Jaladanki N; Zou, Tongtong; Liu, Lan; Marasa, Bernard S; Xiao, Lan; Chen, Jie; Turner, Douglas J; Wang, Jian-Ying

    2007-07-01

    Normal intestinal mucosal growth requires polyamines that regulate expression of various genes involved in cell proliferation, growth arrest, and apoptosis. Our previous studies have shown that polyamine depletion stabilizes p53, resulting in inhibition of intestinal epithelial cell (IEC) proliferation, but the exact downstream targets of induced p53 are still unclear. The NDRG1 (N-myc downregulated gene-1) gene encodes a growth-related protein, and its transcription can be induced in response to stress. The current study tests the hypothesis that induced p53 inhibits IEC proliferation by upregulating NDRG1 expression following polyamine depletion. Depletion of cellular polyamines by inhibiting ornithine decarboxylase (ODC) with alpha-difluoromethylornithine not only induced p53 but also increased NDRG1 transcription as indicated by induction of the NDRG1 promoter activity and increased levels of NDRG1 mRNA and protein, all of which were prevented by using specific p53 siRNA and in cells with a targeted deletion of p53. In contrast, increased levels of cellular polyamines by ectopic expression of the ODC gene decreased p53 and repressed expression of NDRG1. Consistently, polyamine depletion-induced activation of the NDRG1-promoter was decreased when p53-binding sites within the NDRG1 proximal promoter region were deleted. Ectopic expression of the wild-type NDRG1 gene inhibited DNA synthesis and decreased final cell numbers regardless of the presence or absence of endogenous p53, whereas silencing NDRG1 promoted cell growth. However, overexpression of NDRG1 failed to directly induce cell death and to alter susceptibility to apoptosis induced by tumor necrosis factor-alpha/cycloheximide. These results indicate that NDRG1 is one of the direct mediators of induced p53 following polyamine depletion and that p53-dependent NDRG1 expression plays a critical role in the negative control of IEC proliferation.

  20. A novel mouse PKC{delta} splice variant, PKC{delta}IX, inhibits etoposide-induced apoptosis

    SciTech Connect

    Kim, Jung D.; Seo, Kwang W.; Lee, Eun A.; Quang, Nguyen N.; Cho, Hong R.; Kwon, Byungsuk

    2011-07-01

    Highlights: {yields} A novel PKC{delta} isoform, named PKC{delta}IX, that lacks the C1 domain and the ATP-binding site is ubiquitously expressed. {yields} PKC{delta}IX inhibits etoposide-induced apoptosis. {yields} PKC{delta}IX may function as an endogenous dominant negative isoform for PKC{delta}. -- Abstract: Protein kinase C (PKC) {delta} plays an important role in cellular proliferation and apoptosis. The catalytic fragment of PKC{delta} generated by caspase-dependent cleavage is essential for the initiation of etoposide-induced apoptosis. In this study, we identified a novel mouse PKC{delta} isoform named PKC{delta}IX (Genebank Accession No. (HQ840432)). PKC{delta}IX is generated by alternative splicing and is ubiquitously expressed, as seen in its full-length PKC{delta}. PKC{delta}IX lacks the C1 domain, the caspase 3 cleavage site, and the ATP binding site but preserves an almost intact c-terminal catalytic domain and a nuclear localization signal (NLS). The structural characteristics of PKC{delta}IX provided a possibility that this PKC{delta} isozyme functions as a novel dominant-negative form for PKC{delta} due to its lack of the ATP-binding domain that is required for the kinase activity of PKC{delta}. Indeed, overexpression of PKC{delta}IX significantly inhibited etoposide-induced apoptosis in NIH3T3 cells. In addition, an in vitro kinase assay showed that recombinant PKC{delta}IX protein could competitively inhibit the kinase activity of PKC{delta}. We conclude that PKC{delta}IX can function as a natural dominant-negative inhibitor of PKC{delta}in vivo.

  1. KANK1 inhibits cell growth by inducing apoptosis though regulating CXXC5 in human malignant peripheral nerve sheath tumors

    PubMed Central

    Cui, Zhibin; Shen, Yingjia; Chen, Kenny H.; Mittal, Suresh K.; Yang, Jer-Yen; Zhang, GuangJun

    2017-01-01

    Malignant peripheral nerve sheath tumors (MPNSTs) are a type of rare sarcomas with a poor prognosis due to its highly invasive nature and limited treatment options. Currently there is no targeted-cancer therapy for this type of malignancy. Thus, it is important to identify more cancer driver genes that may serve as targets of cancer therapy. Through comparative oncogenomics, we have found that KANK1 was a candidate tumor suppressor gene (TSG) for human MPNSTs. Although KANK1 is known as a cytoskeleton regulator, its tumorigenic function in MPNSTs remains largely unknown. In this study, we report that restoration of KANK1 in human MPNST cells inhibits cell growth both in human cell culture and xenograft mice by increasing apoptosis. Consistently, knockdown of KANK1 in neurofibroma cells promoted cell growth. Using RNA-seq analysis, we identified CXXC5 and other apoptosis-related genes, and demonstrated that CXXC5 is regulated by KANK1. Knockdown of CXXC5 was found to diminish KANK1-induced apoptosis in MPNST cells. Thus, KANK1 inhibits MPNST cell growth though CXXC5 mediated apoptosis. Our results suggest that KANK1 may function as a tumor suppressor in human MPNSTs, and thus it may be useful for targeted therapy. PMID:28067315

  2. Curcumin induces apoptosis and inhibits prostaglandin E(2) production in synovial fibroblasts of patients with rheumatoid arthritis.

    PubMed

    Park, Cheol; Moon, Dong-Oh; Choi, Il-Whan; Choi, Byung Tae; Nam, Taek-Jeong; Rhu, Chung-Ho; Kwon, Taeg Kyu; Lee, Won Ho; Kim, Gi-Young; Choi, Yung Hyun

    2007-09-01

    Rheumatoid arthritis (RA) is a chronic inflammatory disease that is characterized by hyperplasia of the synovial fibroblasts, which is partly the result of decreased apoptosis. This study investigated the mechanisms through which curcumin, a polyphenolic compound from the rhizome of Curcuma longa, exerts its anti-proliferative action in the synovial fibroblasts obtained from patients with RA. Exposure of the synovial fibroblasts to curcumin resulted in growth inhibition and the induction of apoptosis, as measured by MTT assay, fluorescent microscopy and Annexin-V-based assay. RT-PCR and immunoblotting showed that treating the cells with curcumin resulted in the down-regulation of anti-apoptotic Bcl-2 and the X-linked inhibitor of the apoptosis protein as well as the up-regulation of pro-apoptotic Bax expression in a concentration-dependent manner. Curcumin-induced apoptosis was also associated with the proteolytic activation of caspase-3 and caspase-9, and the concomitant degradation of poly(ADP-ribose) polymerase protein. Furthermore, curcumin decreased the expression levels of the cyclooxygenase (COX)-2 mRNA and protein without causing significant changes in the COX-1 levels, which was correlated with the inhibition of prostaglandin E(2) synthesis. These results show that curcumin might help identify a new therapeutic pathway against hyperplasia of the synovial fibroblasts in RA.

  3. PPAR{gamma} ligands induce growth inhibition and apoptosis through p63 and p73 in human ovarian cancer cells

    SciTech Connect

    Kim, Soyeon; Lee, Jae-Jung; Heo, Dae Seog

    2011-03-18

    Research highlights: {yields} PPAR{gamma} ligands increased the rate of apoptosis and inhibition of proliferation in ovarian cancer cells. {yields} PPAR{gamma} ligands induced p63 and p73 expression, but not p53. {yields} p63 and p73 leads to an increase in p21 expression and apoptosis in ovarian cancer cells with treatment PPAR{gamma} ligands. {yields} These findings suggest that PPAR{gamma} ligands suppressed growth of ovarian cancer cells through upregulation of p63 and p73. -- Abstract: Peroxisome proliferator-activated receptor gamma (PPAR{gamma}) agonists, including thiazolidinediones (TZDs), can induce anti-proliferation, differentiation, and apoptosis in various cancer cell types. This study investigated the mechanism of the anticancer effect of TZDs on human ovarian cancer. Six human ovarian cancer cell lines (NIH:OVCAR3, SKOV3, SNU-251, SNU-8, SNU-840, and 2774) were treated with the TZD, which induced dose-dependent inhibition of cell growth. Additionally, these cell lines exhibited various expression levels of PPAR{gamma} protein as revealed by Western blotting. Flow cytometry showed that the cell cycle was arrested at the G1 phase, as demonstrated by the appearance of a sub-G1 peak. This observation was corroborated by the finding of increased levels of Bax, p21, PARP, and cleaved caspase 3 in TGZ-treated cells. Interestingly, when we determined the effect of p53-induced growth inhibition in these three human ovarian cancer cells, we found that they either lacked p53 or contained a mutant form of p53. Furthermore, TGZ induced the expression of endogenous or exogenous p63 and p73 proteins and p63- or p73-directed short hairpin (si) RNAs inhibited the ability of TGZ to regulate expression of p21 in these cells. Thus, our results suggest that PPAR{gamma} ligands can induce growth suppression of ovarian cancer cells and mediate p63 and p73 expression, leading to enhanced growth inhibition and apoptosis. The tumor suppressive effects of PPAR{gamma} ligands

  4. Cimetidine induces apoptosis in gastric cancer cells in vitro and inhibits tumor growth in vivo.

    PubMed

    Jiang, Cheng-Gang; Liu, Fu-Rong; Yu, Miao; Li, Jia-Bin; Xu, Hui-Mian

    2010-03-01

    Cimetidine, a histamine-2 (H2) receptor antagonist, has been demonstrated to have anticancer effects on various types of malignancies. However, the mechanisms of its action on gastric cancer are not completely understood. This study was designed to investigate its antitumor effect and underlying mechanisms in human gastric cancer SGC-7901 and MGC-803 cells. The MTT assay was used to evaluate cell viability, and flow cytometry, acridine orange staining and transmission electron microscopy were used to detect apoptosis, for cultured cells. The protein expression in cells was evaluated by Western blot analysis and colorimetric assay. Gastric tumors were established by subcutaneous injection of SGC-7901 cells in nude BALB/c mice, and cimetidine was administered to the mice. The size of tumors was monitored and the weight of tumors was examined. The exposure of gastric cancer cells to cimetidine resulted in growth inhibition and the induction of apoptosis in a dose-dependent manner. Activation of the caspase cascade for both the extrinsic and intrinsic pathways were demonstrated in vitro, including caspase-8, -9 and -3. We also found that the expression of Bcl-2 protein decreased and the expression of Bax protein increased which lead to an increase of the Bax/Bcl-2 ratio. In mice bearing SGC-7901 xenograft tumors, administration of cimetidine showed a significant decrease of tumor volumes and tumor weight compared with the control. Our results showed that cimetidine exhibited antitumor effects in gastric cancer cells with an induction of apoptosis.

  5. Cholesterol depletion inhibits src family kinase-dependent calcium mobilization and apoptosis induced by rituximab crosslinking

    PubMed Central

    Unruh, Tammy L; Li, Haidong; Mutch, Cathlin M; Shariat, Neda; Grigoriou, Lana; Sanyal, Ratna; Brown, Christopher B; Deans, Julie P

    2005-01-01

    The monoclonal antibody (mAb) rituximab produces objective clinical responses in patients with B-cell non-Hodgkin's lymphoma and antibody-based autoimmune diseases. Mechanisms mediating B-cell depletion by rituximab are not completely understood and may include direct effects of signalling via the target antigen CD20. Like most but not all CD20 mAbs, rituximab induces a sharp change in the solubility of the CD20 protein in the non-ionic detergent Triton-X-100, reflecting a dramatic increase in the innate affinity of CD20 for membrane raft signalling domains. Apoptosis induced by rituximab hypercrosslinking has been shown to require src family kinases (SFK), which are enriched in rafts. In this report we provide experimental evidence that SFK-dependent apoptotic signals induced by rituximab are raft dependent. Cholesterol depletion prevented the association of hypercrosslinked CD20 with detergent-insoluble rafts, and attenuated both calcium mobilization and apoptosis induced with rituximab. CD20 cocapped with the raft-associated transmembrane adaptor LAB/NTAL after hypercrosslinking with CD20 mAbs, regardless of their ability to induce a change in the affinity of CD20 for rafts. Taken together, the data demonstrate that CD20 hypercrosslinking via rituximab activates SFKs and downstream signalling events by clustering membrane rafts in which antibody-bound CD20 is localized in a high-affinity configuration. PMID:16162271

  6. Aloe-emodin, an anthraquinone, in vitro inhibits proliferation and induces apoptosis in human colon carcinoma cells.

    PubMed

    Lin, Kai-Yuan; Uen, Yih-Huei

    2010-05-01

    The present study aimed to investigate the anticancer effect of aloe-emodin, an anthraquinone compound present in the leaves of Aloe vera, on two human colon carcinoma cell lines, DLD-1 and WiDr. Colon carcinoma cells were treated with various concentrations of aloe-emodin for different durations. Cell viability was measured by sodium 3'-[1-(phenylamino-carbonyl)-3,4-tetrazolium]-bis(4-methoxy-6-nitro) benzene-sulfonic acid hydrate assay. DNA fragmentation was analyzed by agarose gel electrophoresis. Nuclear shrinkage was visualized by Hoechst 33258 staining. Western blotting was used to indicate the release of apoptosis-inducing factor and cytochrome c from mitochondria and the phosphorylation of Bid. Caspase-3 and casein kinase II activities were measured by the respective assays. Cell viability analyses showed that aloe-emodin induced cell death in a dose- and time-dependent manner. Notably, the WiDr cells were more sensitive to aloe-emodin than the DLD-1 cells. Aloe-emodin caused the release of apoptosis-inducing factor and cytochrome c from mitochondria, followed by activation of caspase-3 leading to DNA fragmentation, nuclear shrinkage and apoptosis. In addition, exposure of colon carcinoma cells to aloe-emodin suppressed the casein kinase II activity in a time-dependent manner and was accompanied by a reduced phosphorylation of Bid, a downstream substrate of casein kinase II and a pro-apoptotic molecule. These findings showed that the inhibition of casein kinase II activity, the release of apoptosis-inducing factor and cytochrome c, and the caspase-3 activation are involved in aloe-emodin-mediated apoptosis in colon carcinoma cells.

  7. Aloe-emodin, an anthraquinone, in vitro inhibits proliferation and induces apoptosis in human colon carcinoma cells

    PubMed Central

    LIN, KAI-YUAN; UEN, YIH-HUEI

    2010-01-01

    The present study aimed to investigate the anticancer effect of aloe-emodin, an anthraquinone compound present in the leaves of Aloe vera, on two human colon carcinoma cell lines, DLD-1 and WiDr. Colon carcinoma cells were treated with various concentrations of aloe-emodin for different durations. Cell viability was measured by sodium 3′-[1-(phenylamino-carbonyl)-3,4-tetrazolium]-bis(4-methoxy-6-nitro) benzene-sulfonic acid hydrate assay. DNA fragmentation was analyzed by agarose gel electrophoresis. Nuclear shrinkage was visualized by Hoechst 33258 staining. Western blotting was used to indicate the release of apoptosis-inducing factor and cytochrome c from mitochondria and the phosphorylation of Bid. Caspase-3 and casein kinase II activities were measured by the respective assays. Cell viability analyses showed that aloe-emodin induced cell death in a dose- and time-dependent manner. Notably, the WiDr cells were more sensitive to aloe-emodin than the DLD-1 cells. Aloe-emodin caused the release of apoptosis-inducing factor and cytochrome c from mitochondria, followed by activation of caspase-3 leading to DNA fragmentation, nuclear shrinkage and apoptosis. In addition, exposure of colon carcinoma cells to aloe-emodin suppressed the casein kinase II activity in a time-dependent manner and was accompanied by a reduced phosphorylation of Bid, a downstream substrate of casein kinase II and a pro-apoptotic molecule. These findings showed that the inhibition of casein kinase II activity, the release of apoptosis-inducing factor and cytochrome c, and the caspase-3 activation are involved in aloe-emodin-mediated apoptosis in colon carcinoma cells. PMID:22966340

  8. BET Inhibition Induces Apoptosis in Aggressive B-Cell Lymphoma via Epigenetic Regulation of BCL-2 Family Members.

    PubMed

    Hogg, Simon J; Newbold, Andrea; Vervoort, Stephin J; Cluse, Leonie A; Martin, Benjamin P; Gregory, Gareth P; Lefebure, Marcus; Vidacs, Eva; Tothill, Richard W; Bradner, James E; Shortt, Jake; Johnstone, Ricky W

    2016-09-01

    Targeting BET bromodomain proteins using small molecules is an emerging anticancer strategy with clinical evaluation of at least six inhibitors now underway. Although MYC downregulation was initially proposed as a key mechanistic property of BET inhibitors, recent evidence suggests that additional antitumor activities are important. Using the Eμ-Myc model of B-cell lymphoma, we demonstrate that BET inhibition with JQ1 is a potent inducer of p53-independent apoptosis that occurs in the absence of effects on Myc gene expression. JQ1 skews the expression of proapoptotic (Bim) and antiapoptotic (BCL-2/BCL-xL) BCL-2 family members to directly engage the mitochondrial apoptotic pathway. Consistent with this, Bim knockout or Bcl-2 overexpression inhibited apoptosis induction by JQ1. We identified lymphomas that were either intrinsically resistant to JQ1-mediated death or acquired resistance following in vivo exposure. Strikingly, in both instances BCL-2 was strongly upregulated and was concomitant with activation of RAS pathways. Eμ-Myc lymphomas engineered to express activated Nras upregulated BCL-2 and acquired a JQ1 resistance phenotype. These studies provide important information on mechanisms of apoptosis induction and resistance to BET-inhibition, while providing further rationale for the translation of BET inhibitors in aggressive B-cell lymphomas. Mol Cancer Ther; 15(9); 2030-41. ©2016 AACR.

  9. Che-1 gene silencing induces osteosarcoma cell apoptosis by inhibiting mutant p53 expression.

    PubMed

    Liu, Ming; Wang, Dan; Li, Ning

    2016-04-22

    The transcriptional cofactor Che-1 is an RNA polymerase II (Pol II) which is involved in tumorigenesis, such as breast cancer and multiple myeloma. Che-1 can also regulate mutant p53 expression, which plays roles in many types of cancer. In this study, we aimed to investigate the effects and specific mechanism of Che-1 in the regulation of osteosarcoma (OS) cell growth. We found that Che-1 is highly expressed in several kinds of OS cells compared with osteoblast hFOB1.19 cells. MTT and flow cytometry assays showed that Che-1 depletion by siRNA markedly suppressed MG-63 and U2OS cell proliferation and promoted apoptosis. The chromatin immunoprecipitation (ChIP) assay verified the presence of Che-1 on the p53 promoter in MG-63 and U2OS cells carrying mutant p53. Further studies showed that Che-1 depletion inhibited mutant p53 expression. Notably, our study showed that the loss of Che-1 inhibits proliferation and promotes apoptosis in MG-63 cells by decreasing the level of mutant p53. Therefore, these findings open the possibility that silencing of Che-1 will have therapeutic benefit in OS.

  10. SENP1 inhibition induces apoptosis and growth arrest of multiple myeloma cells through modulation of NF-κB signaling

    SciTech Connect

    Xu, Jun; Sun, Hui-Yan; Xiao, Feng-Jun; Wang, Hua; Yang, Yang; Wang, Lu; Gao, Chun-Ji; Guo, Zi-Kuan; Wu, Chu-Tse; Wang, Li-Sheng

    2015-05-01

    SUMO/sentrin specific protease 1 (Senp1) is an important regulation protease in the protein sumoylation, which affects the cell cycle, proliferation and differentiation. The role of Senp1 mediated protein desumoylation in pathophysiological progression of multiple myeloma is unknown. In this study, we demonstrated that Senp1 is overexpressed and induced by IL-6 in multiple myeloma cells. Lentivirus-mediated Senp1 knockdown triggers apoptosis and reduces viability, proliferation and colony forming ability of MM cells. The NF-κB family members including P65 and inhibitor protein IkBα play important roles in regulation of MM cell survival and proliferation. We further demonstrated that Senp1 inhibition decreased IL-6-induced P65 and IkBα phosphorylation, leading to inactivation of NF-kB signaling in MM cells. These results delineate a key role for Senp1in IL-6 induced proliferation and survival of MM cells, suggesting it may be a potential new therapeutic target in MM. - Highlights: • Senp1 is overexpressed and induced by IL-6 in multiple myeloma cells. • Senp1 knockdown triggers apoptosis and reduces proliferation of MM cells. • Senp1 inhibition decreased IL-6-induced P65 and IkBα phosphorylation.

  11. Protective effect of Trillium tschonoskii saponin on CCl4-induced acute liver injury of rats through apoptosis inhibition.

    PubMed

    Wu, Hao; Qiu, Yong; Shu, Ziyang; Zhang, Xu; Li, Renpeng; Liu, Su; Chen, Longquan; Liu, Hong; Chen, Ning

    2016-12-01

    To explore hepatoprotective role and underlying mechanisms of Trillium tschonoskii Maxim (TTM), 36 rats were randomly divided into control, CCl4-induced liver injury model, and biphenyl dimethyl dicarboxylate (DDB) and low-, moderate-, and high-dose TTM treatment groups. After CCl4-induced model establishment, the rats from DDB and TTM groups were administrated with DDB at 0.2 g/kg per day and TTM at 0.1, 0.5, and 1.0 g/kg per day, while the rats from control and model groups were administrated with saline. After 5 days of treatments, all rats were sacrificed for determining serum ALT and AST levels and liver index, examining histopathological changes in liver through HE and TUNEL staining, and evaluating TNF-α and IL-6 mRNA expression by real-time PCR, and caspase-3, Bcl-2, and Bax expression by Western blot. Results indicated that CCl4 could induce acute liver injury and abnormal liver function in rats with obvious hepatomegaly, increased liver index, high ALT and AST levels, up-regulated TNF-α and IL-6, and overexpressed Bax and caspase-3. However, DDB and TTM could execute protective role in CCl4-induced liver injury in rats through reducing ALT and AST levels, rescuing hepatomegaly, down-regulating inflammatory factors and inhibiting hepatocyte apoptosis in a dose-dependent manner. Therefore, TTM has obvious protective role in CCl4-induced liver injury of rats through inhibiting hepatocyte apoptosis.

  12. Inhibition of macroautophagy by bafilomycin A{sub 1} lowers proliferation and induces apoptosis in colon cancer cells

    SciTech Connect

    Wu, Ya Chun; Wu, William Ka Kei; Li, Youming; Yu, Le; Li, Zhi Jie; Wong, Clover Ching Man; Li, Hai Tao; Sung, Joseph Jao Yiu; Cho, Chi Hin

    2009-05-01

    Macroautophagy is a process by which cytoplasmic content and organelles are sequestered by double-membrane bound vesicles and subsequently delivered to lysosomes for degradation. Macroautophagy serves as a major intracellular pathway for protein degradation and as a pro-survival mechanism in time of stress by generating nutrients. In the present study, bafilomycin A{sub 1}, a vacuolar type H{sup +}-ATPase inhibitor, suppresses macroautophagy by preventing acidification of lysosomes in colon cancer cells. Diminished macroautophagy was evidenced by the accumulation of undegraded LC3 protein. Suppression of macroautophagy by bafilomycin A{sub 1} induced G{sub 0}/G{sub 1} cell cycle arrest and apoptosis which were accompanied by the down-regulation of cyclin D{sub 1} and cyclin E, the up-regulation of p21{sup Cip1} as well as cleavages of caspases-3, -7, -8, and -9 and PARP. Further investigation revealed that bafilomycin A{sub 1} increased the phosphorylation of ERK, JNK, and p38. In this regard, p38 inhibitor partially reversed the anti-proliferative effect of bafilomycin A{sub 1}. To conclude, inhibition of macroautophagy by bafilomycin A{sub 1} lowers G{sub 1}-S transition and induces apoptosis in colon cancer cells. Our results not only indicate that inhibitors of macroautophagy may be used therapeutically to inhibit cancer growth, but also delineate the relationship between macroautophagy and apoptosis.

  13. miR-503 inhibits cell proliferation and induces apoptosis in colorectal cancer cells by targeting E2F3

    PubMed Central

    Chang, Shun-Wu; Yue, Jie; Wang, Bao-Chun; Zhang, Xue-Li

    2015-01-01

    Objective: Colorectal cancer (CRC) is one of the major healthcare problems worldwide. A lot of miRNAs are aberrantly expressed in CRC and involved in its development and progression. The purpose of this study was to investigate the expression and function of miR-503 in CRC. Methods: miR-503 expression was detected in CRC tissues and cell lines by Quantitative real-time PCR. Cell proliferation was assessed by MTT assay. Cell apoptosis and cell cycle distribution were measured by flow cytometry. Moreover, luciferase reporter assay and western blot were performed to determine the potential target of miR-503 in CRC cells. Results: miR-503 was significantly decreased in CRC tissues and cell lines in comparison with controls. Overexpression of miR-503 in CRC cells remarkably inhibited cell proliferation and induced apoptosis. Furthermore, E2F3 was identified as a direct target of miR-503 in CRC cells and down-regulation of E2F3 had a similar effect as miR-503 overexpression on CRC cells. In addition, the expression of E2F3 was negatively correlated with miR-503 level in CRC tissues. Conclusions: miR-503 inhibits cell proliferation and induces apoptosis by directly targeting E2F3 in CRC cells, indicating its potential application in CRC diagnosis and therapy. PMID:26722476

  14. Identification of small molecules that induce apoptosis in a Myc-dependent manner and inhibit Myc-driven transformation

    PubMed Central

    Mo, Hao; Henriksson, Marie

    2006-01-01

    The Myc transcription factor plays a central role in the regulation of cell cycle progression, apoptosis, angiogenesis, and cellular transformation. Myc is a potent oncoprotein that is deregulated in a wide variety of human tumors and is therefore an attractive target for novel cancer therapies. Using a cellular screening approach, we have identified low-molecular-weight compounds, Myc pathway response agents (MYRAs), that induce apoptosis in a c-Myc-dependent manner and inhibit Myc-driven cellular transformation. MYRA-A inhibits Myc transactivation and interferes with the DNA-binding activity of Myc family proteins but has no effect on the E-box-binding protein USF. In contrast, MYRA-B induces Myc-dependent apoptosis without affecting Myc transactivation or Myc/Max DNA binding. Our data show that cellular screening assays can be a powerful strategy for the identification of candidate substances that modulate the Myc pathway. These compounds can be useful tools for studying Myc function and may also be of therapeutic potential as leads for drug development. PMID:16606833

  15. Alpha Cyano-4-Hydroxy-3-Methoxycinnamic Acid Inhibits Proliferation and Induces Apoptosis in Human Breast Cancer Cells

    PubMed Central

    Hamdan, Lamia; Arrar, Zoheir; Al Muataz, Yacoub; Suleiman, Lutfi; Négrier, Claude; Mulengi, Joseph Kajima; Boukerche, Habib

    2013-01-01

    This study investigated the underlying mechanism of 4-hydroxy-3-methoxycinnamic acid (ACCA), on the growth of breast cancer cells and normal immortal epithelial cells, and compared their cytotoxic effects responses. Treatment of breast cancer cells (MCF-7, T47D, and MDA-231) with ACCA resulted in dose- and time-dependent decrease of cell proliferation, viability in colony formation assay, and programmed cell death (apoptosis) with minimal effects on non-tumoral cells. The ability of ACCA to suppress growth in cancer cells not expressing or containing defects in p53 gene indicates a lack of involvement of this critical tumor suppressor element in mediating ACCA-induced growth inhibition. Induction of apoptosis correlated with an increase in Bax protein, an established inducer of programmed cell death, and the ratio of Bax to Bcl-2, an established inhibitor of apoptosis. We also documented the ability of ACCA to inhibit the migration and invasion of MDA-231 cells with ACCA in vitro. Additionally, tumor growth of MDA-231 breast cancer cells in vivo was dramatically affected with ACCA. On the basis of its selective anticancer inhibitory activity on tumor cells, ACCA may represent a promising therapeutic drug that should be further evaluated as a chemotherapeutic agent for human breast cancer. PMID:24039831

  16. Alpha cyano-4-hydroxy-3-methoxycinnamic acid inhibits proliferation and induces apoptosis in human breast cancer cells.

    PubMed

    Hamdan, Lamia; Arrar, Zoheir; Al Muataz, Yacoub; Suleiman, Lutfi; Négrier, Claude; Mulengi, Joseph Kajima; Boukerche, Habib

    2013-01-01

    This study investigated the underlying mechanism of 4-hydroxy-3-methoxycinnamic acid (ACCA), on the growth of breast cancer cells and normal immortal epithelial cells, and compared their cytotoxic effects responses. Treatment of breast cancer cells (MCF-7, T47D, and MDA-231) with ACCA resulted in dose- and time-dependent decrease of cell proliferation, viability in colony formation assay, and programmed cell death (apoptosis) with minimal effects on non-tumoral cells. The ability of ACCA to suppress growth in cancer cells not expressing or containing defects in p53 gene indicates a lack of involvement of this critical tumor suppressor element in mediating ACCA-induced growth inhibition. Induction of apoptosis correlated with an increase in Bax protein, an established inducer of programmed cell death, and the ratio of Bax to Bcl-2, an established inhibitor of apoptosis. We also documented the ability of ACCA to inhibit the migration and invasion of MDA-231 cells with ACCA in vitro. Additionally, tumor growth of MDA-231 breast cancer cells in vivo was dramatically affected with ACCA. On the basis of its selective anticancer inhibitory activity on tumor cells, ACCA may represent a promising therapeutic drug that should be further evaluated as a chemotherapeutic agent for human breast cancer.

  17. Combination of α-Tomatine and Curcumin Inhibits Growth and Induces Apoptosis in Human Prostate Cancer Cells

    PubMed Central

    Li, Dongli; He, Yan; Li, Yu; Du, Zhiyun; Zhang, Kun; DiPaola, Robert; Goodin, Susan; Zheng, Xi

    2015-01-01

    α-Tomatine is a glycoalkaloid found in tomatoes and curcumin is a major yellow pigment of turmeric. In the present study, the combined effect of these two compounds on prostate cancer cells was studied. Treatment of different prostate cancer cells with curcumin or α-tomatine alone resulted in growth inhibition and apoptosis in a concentration-dependent manner. Combinations of α-tomatine and curcumin synergistically inhibited the growth and induced apoptosis in prostate cancer PC-3 cells. Effects of the α-tomatine and curcumin combination were associated with synergistic inhibition of NF-κB activity and a potent decrease in the expression of its downstream gene Bcl-2 in the cells. Moreover, strong decreases in the levels of phospho-Akt and phosphor-ERK1/2 were found in PC-3 cells treated with α-tomatine and curcumin in combination. In animal experiment, SCID mice with PC-3 xenograft tumors were treated with α-tomatine and curcumin. Combination of α-tomatine and curcumin more potently inhibited the growth of PC-3 tumors than either agent alone. Results from the present study indicate that α-tomatine in combination with curcumin may be an effective strategy for inhibiting the growth of prostate cancer. PMID:26630272

  18. Electroacupuncture preconditioning and postconditioning inhibit apoptosis and neuroinflammation induced by spinal cord ischemia reperfusion injury through enhancing autophagy in rats.

    PubMed

    Fang, Bo; Qin, Meiman; Li, Yun; Li, Xiaoqian; Tan, Wenfei; Zhang, Ying; Ma, Hong

    2017-03-06

    Electroacupuncture (EA) has beneficial effects on spinal cord ischemia reperfusion (I/R) injury, but the underlying mechanisms are not fully understood. This study aimed to investigate the role of autophagy in the protection of EA preconditioning and postconditioning against spinal cord I/R injury. For this, spinal cord I/R injury was induced by 14min occlusion of the aortic arch, and rats were treated with EA for 20min before or after the surgery. The expression of autophagy components, light chain 3 and Beclin 1, was assessed by Western blot. The hind-limb motor function was assessed using the Basso-Beattie-Bresnahan (BBB) criteria, and motor neurons in the ventral gray matter were counted by histological examination. The apoptosis of neurocyte was assessed by the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) assay. The expression of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and matrix metalloproteinase-9 (MMP-9) was also measured using Western blot or enzyme-linked immunosorbent assay (ELISA). Either EA preconditioning or postconditioning enhanced autophagy, and minimized the neuromotor dysfunction and histopathological deficits after spinal cord I/R injury. In addition, EA suppressed I/R-induced apoptosis and increased in the expression of TNF-α, IL-1β, and MMP-9. In contrast, the autophagic inhibitor (3-methyladenine, 3-MA) inhibited the neuroprotective effects of EA. Moreover, 3-MA increased the apoptosis and the expression of TNF-α, IL-1β, and MMP-9. In summary, these findings suggested that EA preconditioning and postconditioning could alleviate spinal cord I/R injury, which was partly mediated by autophagy upregulation-induced inhibition of apoptosis and neuroinflammation.

  19. Inhibition of store-operated Ca2+ entry counteracts the apoptosis of nasopharyngeal carcinoma cells induced by sodium butyrate

    PubMed Central

    Huang, Wei; Ren, Caiping; Huang, Guoling; Liu, Jie; Liu, Weidong; Wang, Lei; Zhu, Bin; Feng, Xiangling; Shi, Jia; Li, Jinlong; Xia, Xiaomeng; Jia, Wei; Chen, Jiawen; Chen, Yuxiang; Jiang, Xingjun

    2017-01-01

    Sodium butyrate (NaBu), a histone deacetylase inhibitor, has demonstrated anti-tumor effects in several cancers, and is a promising candidate chemotherapeutic agent. However, its roles in nasopharyngeal carcinoma (NPC), an endemic malignant disease in Southern China and Southeast Asia, has rarely been studied. In the present study, MTT assay, colony formation assay, flow cytometry analysis and western blotting were performed to explore the influence of NaBu on NPC cells and its underlying mechanism. NaBu induced morphological changes and inhibited proliferation in 5–8F and 6–10B cells. MTT assay revealed that NaBu was cytotoxic to 5–8F and 6–10B cells in a dose- and time-dependent manner. Furthermore, flow cytometry analysis revealed that NaBu induced obvious cell apoptosis in 5–8F and 6–10B cells due to the activation of the mitochondrial apoptosis axis. In addition, flow cytometry analysis and western blotting demonstrated that NaBu could enhance the Ca2+ influx by promoting store-operated Ca2+ entry (SOCE) in 5–8F and 6–10B cells. Inhibition of SOCE by specific inhibitors or downregulated expression of calcium release-activated calcium channel protein 1 and stromal interaction molecule 1 could counteract the apoptosis of NPC cells induced by NaBu. Thus, the current study revealed that enhanced SOCE and activated mitochondrial apoptosis axis may account for the mechanisms of cytotoxicity of NaBu in NPC cells, and that NaBu serves as a promising chemotherapeutic agent in NPC therapy. PMID:28356979

  20. Indirubin derivatives induce apoptosis of chronic myelogenous leukemia cells involving inhibition of Stat5 signaling.

    PubMed

    Nam, Sangkil; Scuto, Anna; Yang, Fan; Chen, Wenyong; Park, Sungman; Yoo, Hwa-Seung; Konig, Heiko; Bhatia, Ravi; Cheng, Xinlai; Merz, Karl-Heinz; Eisenbrand, Gerhard; Jove, Richard

    2012-06-01

    Indirubin is the major active anti-tumor component of a traditional Chinese herbal medicine used for treatment of chronic myelogenous leukemia (CML). While previous studies indicate that indirubin is a promising therapeutic agent for CML, the molecular mechanism of action of indirubin is not fully understood. We report here that indirubin derivatives (IRDs) potently inhibit Signal Transducer and Activator of Transcription 5 (Stat5) protein in CML cells. Compound E804, which is the most potent in this series of IRDs, blocked Stat5 signaling in human K562 CML cells, imatinib-resistant human KCL-22 CML cells expressing the T315I mutant Bcr-Abl (KCL-22M), and CD34-positive primary CML cells from patients. Autophosphorylation of Src family kinases (SFKs) was strongly inhibited in K562 and KCL-22M cells at 5 μM E804, and in primary CML cells at 10 μM E804, although higher concentrations partially inhibited autophosphorylation of Bcr-Abl. Previous studies indicate that SFKs cooperate with Bcr-Abl to activate downstream Stat5 signaling. Activation of Stat5 was strongly blocked by E804 in CML cells. E804 down-regulated expression of Stat5 target proteins Bcl-x(L) and Mcl-1, associated with induction of apoptosis. In sum, our findings identify IRDs as potent inhibitors of the SFK/Stat5 signaling pathway downstream of Bcr-Abl, leading to apoptosis of K562, KCL-22M and primary CML cells. IRDs represent a promising structural class for development of new therapeutics for wild type or T315I mutant Bcr-Abl-positive CML patients.

  1. Columbianadin Inhibits Cell Proliferation by Inducing Apoptosis and Necroptosis in HCT116 Colon Cancer Cells

    PubMed Central

    Kang, Ji In; Hong, Ji-Young; Choi, Jae Sue; Lee, Sang Kook

    2016-01-01

    Columbianadin (CBN), a natural coumarin from Angelica decursiva (Umbelliferae), is known to have various biological activities including anti-inflammatory and anti-cancer effects. In this study, the anti-proliferative mechanism of actions mediated by CBN was investigated in HCT-116 human colon cancer cells. CBN effectively suppressed the growth of colon cancer cells. Low concentration (up to 25 μM) of CBN induced apoptosis, and high concentration (50 μM) of CBN induced necroptosis. The induction of apoptosis by CBN was correlated with the modulation of caspase-9, caspase-3, Bax, Bcl-2, Bim and Bid, and the induction of necroptosis was related with RIP-3, and caspase-8. In addition, CBN induced the accumulation of ROS and imbalance in the intracellular antioxidant enzymes such as SOD-1, SOD-2, catalase and GPx-1. These findings demonstrate that CBN has the potential to be a candidate in the development of anti-cancer agent derived from natural products. PMID:27098859

  2. The mechanism of PDT-induced apoptosis

    NASA Astrophysics Data System (ADS)

    Cai, Xiongwei; Liu, Timon C.; Ding, Xin-Min; Gu, Ying; Liu, Fan-Guang; Liu, Song-Hao

    2003-12-01

    Photodynamic therapy (PDT) can induce apoptosis in many cancer cells in vitro and in tumors in vivo. Cells become more oxidation with PDT, and maintain differentiation and proliferation, go apoptosis and necrosis with the increase of reactive oxygen species (ROS) concentration. ROS can induce apoptosis through mitochondria by inhibiting respiration chain or oxidative phosphorylation or damaging mitochondrial membrane. ROS can initiate apoptosis through endoplamic reticulum(ER) by opening Ca2+ channel or starting unfold protein response (UPR). ROS can also induce apoptosis through Golgi by producing ganglioside GD3 by use of ceramide, which induces apoptosis by activating caspase-3, JNK and p38 MAPK. It can also induce apoptosis by activating Bip (mitochondria-dependant) or preocaspase-12 (mitochondria- independent) or inhibiting protein synthesizing. There are so complicated cross-talking among different signal pathways or organnells that we think PDT-induced apoptosis is mediated by multiplex pathways and excessive levels in a refined network.

  3. Inhibition of c-Jun N-terminal kinase sensitizes tumor cells to flavonoid-induced apoptosis through down-regulation of JunD

    SciTech Connect

    Kook, Sung-Ho; Son, Young-Ok; Jang, Yong-Suk; Lee, Kyung-Yeol; Lee, Seung-Ah; Kim, Beom-Soo; Lee, Hyun-Jeong; Lee, Jeong-Chae

    2008-03-15

    Reduction of susceptibility to apoptosis signals is a crucial step in carcinogenesis. Therefore, sensitization of tumor cells to apoptosis is a promising therapeutic strategy. c-Jun NH{sub 2}-terminal kinase (JNK) has been implicated in stress-induced apoptosis. However, many studies also emphasize the role of JNK on cell survival, although its mechanisms are not completely understood. Previously, we found that inhibition of JNK activity promotes flavonoid-mediated apoptosis of human osteosarcoma cells. We thus determined whether inhibition of JNK sensitizes tumor cells to a bioflavonoid-induced apoptosis, and whether this effect of JNK is a general effect. As the results, quercetin and genistein as well as a flavonoid fraction induced apoptosis of tumor cells, which was further accelerated by specific JNK inhibitor, SP600125 or by small interfering RNA specific to JNK1/2. This effect was specific to types of cells because it was further apparent in tumorigenic cell lines. Inhibition of JNK by SP600125 also reduced flavonoid-stimulated nuclear induction of JunD which was known to have protective role in apoptosis, whereas JNK inhibition alone had little effect on apoptosis. The flavonoid-induced apoptosis of tumor cells was significantly enhanced by transfecting them with antisense JunD oligonucleotides. These results suggest that inhibition of JNK facilitates flavonoid-induced apoptosis through down-regulation of JunD, which is further sensitive to tumor cells. Therefore, combination with a specific JNK inhibitor further enhances the anti-cancer and chemopreventive potential of bio-flavonoids.

  4. Caspase-mediated cleavage of Beclin1 inhibits autophagy and promotes apoptosis induced by S1 in human ovarian cancer SKOV3 cells.

    PubMed

    Li, Xiaoning; Su, Jing; Xia, Meihui; Li, Hongyan; Xu, Ye; Ma, Chunhui; Ma, Liwei; Kang, Jingsong; Yu, Huimei; Zhang, Zhichao; Sun, Liankun

    2016-02-01

    S1, a novel BH3 mimetic, can induce apoptosis dependent on Bax/Bak through inhibition of Bcl-2 in various tumors. S1 also induces autophagy through interrupting the interaction of Bcl-2 and Beclin1. Our results showed that S1 induces apoptosis in human ovarian cancer SKOV3 cells in a time- and dose-dependent manner. Autophagy precedes apoptosis, in SKOV3 cells treated with S1 (6 μmol/L), autophagy reached the maximum peak at 12 h after treatment and decreased to 24 h. In SKOV3 cells treated with different concentrations of S1 for 24 h, the highest level of autophagy was observed with 5 μmol/L and decreased to 10 μmol/L. Autophagy inhibitors 3-MA and CQ enhanced apoptosis induced by S1 in SKOV3 cells. However, overactivation of caspases in apoptosis induced by S1 may inhibit the autophagy-inducing function of Beclin1. Because the pan-caspase inhibitor Z-VAD recovered the autophagy-inducing function of Beclin1 through reduction of activated caspase-mediated cleavage of Beclin1. Furthermore, the Beclin1 cleavage products could further increase apoptosis induced by S1 in SKOV3 cells. This indicates that apoptosis induced by high doses and long exposure of S1 causes the overactivation of caspases and subsequent cleavage of Beclin1, and inhibits the protection of autophagy. Moreover, the cleaved product of Beclin1 further promotes apoptosis induced by S1 in SKOV3 cells. Our results suggest this may be a molecular mechanism for enhancing the sensitivity of cancer cells to apoptosis induced by small molecular compound targeting Bcl-2.

  5. Proliferation of rabbit chondrocyte and inhibition of IL-1β-induced apoptosis through MEK/ERK signaling by statins.

    PubMed

    Zhou, Bin; Chen, Deheng; Xu, Huazi; Zhang, Xiaolei

    2017-02-01

    Chondrocyte plays a critical role in endochondral ossification and cartilage repair by maintaining the cartilaginous matrix. Statins have been widely used to lower the cholesterol level in patients with cardiovascular disorders. Previous research has demonstrated potential role of statins in chondrocyte proliferation. This study addresses the proliferation-regulatory effect of lovastatin in rabbit chondrocytes as well as the underlying signaling mechanisms, thereby exploring its potential application in chondrocyte-related disorders, such as cartilage damage and osteoarthritis. Rabbit chondrocytes were treated with lovastatin at multiple concentrations, and the proliferation rate was measured by CCK-8 test. The results showed significant increase in chondrocyte proliferation under lovastatin treatment. Using real-time quantitative PCR, it was observed that the expression levels of COL2A1, SOX-9, Caspase-3, and MMP-3 genes were significantly changed by lovastatin treatment. Western blotting analysis showed that the abundance of COL2A1, SOX-9, MEK1/2, p-MEK1/2, ERK1/2, p-ERK1/2, Caspase-3, and MMP-3 proteins was also significantly influenced by lovastatin treatment. Interleukine-1 beta (IL-1β) is involved in the progression of osteoarthritis (OA) by inducing articular cartilage and chondrocyte aging and senescence. In this study, we observed that lovastatin treatment inhibited IL-1β-induced chondrocyte apoptosis, while the combined treatment of lovastatin and U0126 evidently offset the apoptosis-inhibiting effect of lovastatin in chondrocyte proliferation. The expressional level and protein abundance of COL2A1, SOX-9, MEK1/2, p-MEK1/2, ERK1/2, p-ERK1/2, caspase-3, and MMP-3 genes showed significant alterations under the combined treatment. Together, our results suggested that lovastatin significantly promoted proliferation and inhibited the IL-1β-induced apoptosis in rabbit chondrocytes, which was mediated by the MEK/ERK signaling.

  6. Oncostatin M stimulates proliferation, induces collagen production and inhibits apoptosis of human lung fibroblasts

    PubMed Central

    Scaffidi, Amelia K; Mutsaers, Steven E; Moodley, Yuben P; McAnulty, Robin J; Laurent, Geoffrey J; Thompson, Philip J; Knight, Darryl A

    2002-01-01

    Oncostatin M (OSM), a member of the interleukin-6 (IL-6) cytokine family, acts on a variety of cells and elicits diversified biological responses, suggesting potential roles in the regulation of cell survival, differentiation and proliferation.We have examined the effect of OSM on the regulation of human lung fibroblast proliferation, collagen production and spontaneous apoptosis. The proliferative effects of OSM (0.5 – 100 ng ml−1) were assessed using a MTS assay as well as [3H]-thymidine incorporation and cell counts at 24 and 48 h. Hydroxyproline was measured as an index of procollagen production by high pressure liquid chromotography (HPLC). Apoptosis was determined by annexin staining.OSM enhanced the mitotic activity of lung fibroblasts in a time and dose dependent manner. Maximum proliferation of 57% above control was observed after incubation for 48 h with 2 ng ml−1 OSM (P<0.05).Incubation with the mitogen activated protein kinase (MAPK) kinase inhibitor, PD98059 or the tyrosine kinase inhibitor, genestein both significantly reduced the mitogenic effect of OSM (P<0.05).In contrast, proliferation in response to OSM was not regulated by induction of cyclo-oxygenase and subsequent prostaglandin E2 (PGE2) release or by IL-6.OSM also stimulated fibroblasts to synthesize pro-collagen by a maximum of 35% above control levels after 48 h (P<0.05).OSM significantly inhibited the spontaneous apoptosis of fibroblasts at 24 and 48 h.These results provide evidence that OSM has pro-fibrotic properties and suggest that it may play a role in normal lung wound repair and fibrosis. PMID:12086989

  7. Rosiglitazone inhibits cell proliferation by inducing G1 cell cycle arrest and apoptosis in ADPKD cyst-lining epithelia cells.

    PubMed

    Liu, Yawei; Dai, Bing; Fu, Lili; Jia, Jieshuang; Mei, Changlin

    2010-06-01

    Abnormal proliferation is an important pathological feature of autosomal dominant polycystic kidney disease (ADPKD). Many drugs inhibiting cell proliferation have been proved to be effective in slowing the disease progression in ADPKD. Recent evidence has suggested that peroxisome proliferator-activated receptor gamma (PPARgamma) ligands have anti-neoplasm effects through inhibiting cell growth and inducing cell apoptosis in various cancer cells. In the present study, we examined the expression of PPARgamma in human ADPKD kidney tissues and cyst-lining epithelial cell line, and found that the expression of PPARgamma was greater in ADPKD kidney tissues and cyst-lining epithelial cell line than in normal kidney tissues and human kidney cortex (HKC) cell line. Rosiglitazone inhibited significantly proliferation of cyst-lining epithelial cells in a concentration- and time-dependent manner. These effects were diminished by GW9662, a specific PPARgamma antagonist. Cell cycle analysis showed a G0/G1 arrest in human ADPKD cyst-lining epithelial cells with rosiglitazone treatment. Analysis of cell cycle regulatory proteins revealed that rosiglitazone decreased the protein levels of proliferating cell nuclear antigen, pRb, cyclin D1, cyclin D2 and Cdk4 but increased the levels of p21 and p27 in a dose-dependent manner. Rosiglitazone also induced apoptosis in cyst-lining epithelial cells, which was correlated with increased bax expression and decreased bcl-2 expression. These results suggest PPARgamma agonist might serve as a promising drug for the treatment of ADPKD.

  8. Cyproheptadine-induced myeloma cell apoptosis is associated with inhibition of the PI3K/AKT signaling.

    PubMed

    Li, Jie; Cao, Biyin; Zhou, Shunye; Zhu, Jingyu; Zhang, Zubin; Hou, Tingjun; Mao, Xinliang

    2013-12-01

    Recent studies revealed that the anti-allergic cyproheptadine displays anti-blood cancer activity. However, its mechanism is still elusive. In this study, cyproheptadine was found to decrease the expression of anti-apoptotic proteins, including Bcl-2, Mcl-1, and XIAP. More importantly, cyproheptadine-induced apoptosis was accompanied by suppressing AKT activation in myeloma cells. In the subsequent study, cyproheptadine was found to inhibit insulin-like growth factor 1-triggered AKT activation in a time- and concentration-dependent manner. Specifically, cyproheptadine blocked AKT translocation from nuclei for phosphorylation. This inhibition led to suppressed activation of p70S6K and 4EBP1, two key downstream signaling proteins in the PI3K/AKT pathway. However, cyproheptadine did not display inhibition on activation of IGF-1R or STAT3, possible upstream signals of AKT activation. These results further demonstrated that cyproheptadine suppresses the PI3K/AKT signaling pathway, which is probably critical for cyproheptadine-induced MM cell apoptosis.

  9. Inhibition of calcium-activated chloride channel ANO1 suppresses proliferation and induces apoptosis of epithelium originated cancer cells.

    PubMed

    Guan, Lizhao; Song, Yan; Gao, Jian; Gao, Jianjun; Wang, KeWei

    2016-11-29

    ANO1, a calcium-activated chloride channel, has been reported to be amplified or overexpressed in tissues of several cancers. However, reports on its roles in tumor progression obtained from cancer cell lines are inconsistent, suggesting that the role of ANO1 in tumorigenesis is likely dependent on either its expression level or cell-type expressing ANO1. To investigate the biological roles of ANO1 in different tumor cells, we, in this study, selected several cancer cell lines and a normal HaCaT cell line with high expression levels of ANO1, and examined the function of ANO1 in these cells using approaches of lentiviral knockdown and pharmacological inhibition. We found that ANO1 knockdown significantly inhibited cell proliferation and induced cell apoptosis in either tumor cell lines or normal HaCaT cell line. Moreover, silencing ANO1 arrested cancer cells at G1 phase of cell cycle. Treatment with ANO1 inhibitor CaCCinh-A01 reduced cell viability in a dose-dependent manner. Furthermore, both ANO1 inhibitors CaCCinh-A01 and T16Ainh-A01 significantly suppressed cell migration. Our findings show that ANO1 overexpression promotes cancer cell proliferation and migration; and genetic or pharmacological inhibition of ANO1 induces apoptosis and cell cycle arrest at G1 phase in different types of epithelium-originated cancer cells.

  10. Inhibition of calcium-activated chloride channel ANO1 suppresses proliferation and induces apoptosis of epithelium originated cancer cells

    PubMed Central

    Guan, Lizhao; Song, Yan; Gao, Jian; Gao, Jianjun; Wang, KeWei

    2016-01-01

    ANO1, a calcium-activated chloride channel, has been reported to be amplified or overexpressed in tissues of several cancers. However, reports on its roles in tumor progression obtained from cancer cell lines are inconsistent, suggesting that the role of ANO1 in tumorigenesis is likely dependent on either its expression level or cell-type expressing ANO1. To investigate the biological roles of ANO1 in different tumor cells, we, in this study, selected several cancer cell lines and a normal HaCaT cell line with high expression levels of ANO1, and examined the function of ANO1 in these cells using approaches of lentiviral knockdown and pharmacological inhibition. We found that ANO1 knockdown significantly inhibited cell proliferation and induced cell apoptosis in either tumor cell lines or normal HaCaT cell line. Moreover, silencing ANO1 arrested cancer cells at G1 phase of cell cycle. Treatment with ANO1 inhibitor CaCCinh-A01 reduced cell viability in a dose-dependent manner. Furthermore, both ANO1 inhibitors CaCCinh-A01 and T16Ainh-A01 significantly suppressed cell migration. Our findings show that ANO1 overexpression promotes cancer cell proliferation and migration; and genetic or pharmacological inhibition of ANO1 induces apoptosis and cell cycle arrest at G1 phase in different types of epithelium-originated cancer cells. PMID:27732935

  11. Mevalonate Cascade Inhibition by Simvastatin Induces the Intrinsic Apoptosis Pathway via Depletion of Isoprenoids in Tumor Cells

    PubMed Central

    Alizadeh, Javad; Zeki, Amir A.; Mirzaei, Nima; Tewary, Sandipan; Rezaei Moghadam, Adel; Glogowska, Aleksandra; Nagakannan, Pandian; Eftekharpour, Eftekhar; Wiechec, Emilia; Gordon, Joseph W.; Xu, Fred. Y.; Field, Jared T.; Yoneda, Ken Y.; Kenyon, Nicholas J.; Hashemi, Mohammad; Hatch, Grant M.; Hombach-Klonisch, Sabine; Klonisch, Thomas; Ghavami, Saeid

    2017-01-01

    The mevalonate (MEV) cascade is responsible for cholesterol biosynthesis and the formation of the intermediate metabolites geranylgeranylpyrophosphate (GGPP) and farnesylpyrophosphate (FPP) used in the prenylation of proteins. Here we show that the MEV cascade inhibitor simvastatin induced significant cell death in a wide range of human tumor cell lines, including glioblastoma, astrocytoma, neuroblastoma, lung adenocarcinoma, and breast cancer. Simvastatin induced apoptotic cell death via the intrinsic apoptotic pathway. In all cancer cell types tested, simvastatin-induced cell death was not rescued by cholesterol, but was dependent on GGPP- and FPP-depletion. We confirmed that simvastatin caused the translocation of the small Rho GTPases RhoA, Cdc42, and Rac1/2/3 from cell membranes to the cytosol in U251 (glioblastoma), A549 (lung adenocarcinoma) and MDA-MB-231(breast cancer). Simvastatin-induced Rho-GTP loading significantly increased in U251 cells which were reversed with MEV, FPP, GGPP. In contrast, simvastatin did not change Rho-GTP loading in A549 and MDA-MB-231. Inhibition of geranylgeranyltransferase I by GGTi-298, but not farnesyltransferase by FTi-277, induced significant cell death in U251, A549, and MDA-MB-231. These results indicate that MEV cascade inhibition by simvastatin induced the intrinsic apoptosis pathway via inhibition of Rho family prenylation and depletion of GGPP, in a variety of different human cancer cell lines. PMID:28344327

  12. Upregulation of PEDF expression by PARP inhibition contributes to the decrease in hyperglycemia-induced apoptosis in HUVECs

    SciTech Connect

    Chen Haibing; Jia Weiping; Xu Xun; Fan Ying; Zhu Dongqing; Wu Haixiang; Xie Zhenggao; Zheng Zhi

    2008-05-02

    Poly(ADP-ribose)polymerase (PARP) inhibitors decrease angiogenesis through reducing vascular endothelium growth factor (VEGF) induced proliferation, migration, and tube formation of human umbilical vein endothelial cells (HUVECs). In contrast to VEGF, pigment epithelium-derived factor (PEDF) has been demonstrated to act as a strong endogenous inhibitor of angiogenesis. Here, we show that PARP inhibition with a specific inhibitor PJ-34 or specific PARP antisense oligonucleotide upregulates hyperglycemia-induced PEDF expression in HUVECs in a dose-dependent manner. This results in the retard of activation of p38 MAP kinase and the concomitant decrease in cell apoptosis. These results give the first direct demonstration that PEDF might represent a target for PARP inhibition treatment and the effects of PEDF on endothelial cells growth are context dependent.

  13. Epigallocatechin-3-Gallate Inhibits Ethanol-Induced Apoptosis Through Neurod1 Regulating CHOP Expression in Pancreatic β-Cells.

    PubMed

    Wu, Tijun; Xiang, Jie; Shan, Wei; Li, Mengxiao; Zhou, Wenbo; Han, Xiao; Chen, Fang

    2016-05-01

    Epiga-llocatechin-3-gallate (EGCG) is one kind of polyphenol abundant extracted from green tea which has a potent antidiabetic activity. However, the molecular mechanisms mediating the protection procession of EGCG are still unclear. The aim of this study was to investigate the protective effect of EGCG on pancreatic β-cells exposed to ethanol and the possible underlying mechanisms. To observe the effect of EGCG, we assessed apoptosis in βTC-6 and INS-1 cells, which were in complete medium containing 60 mM ethanol, or coincubation with different concentration of EGCG. We also evaluated the roles of Neurod1 in CHOP expression and ethanol-mediated damage through plasmid overexpression. Treatment with EGCG decreased CHOP expression and apoptosis, whereas its treatment increased Neurod1 expression in ethanol-treated βTC-6 and INS-1 cells. Overexpression of Neurod1 caused the decrease of CHOP expression and apoptosis in ethanol-treated cells. Furthermore, Neurod1 inhibited CHOP expression by deacetylation of Histone H4 at the CHOP gene promoter. In addition, EGCG partially restores the activity of Neurod1 binding to CHOP promoter in ethanol-treated cells. In conclusion, EGCG protected β-cell against ethanol-induced β-cell apoptosis by Neurod1 regulating CHOP expression.

  14. γ-terpineol inhibits cell growth and induces apoptosis in human liver cancer BEL-7402 cells in vitro.

    PubMed

    Wu, Zi-Li; Yin, Zhong-Qiong; Du, Yong-Hua; Feng, Rui-Zhang; Ye, Kui-Chuan; Wei, Qin; Hu, Yong; He, Lin; Liao, Lin; Wang, Yu

    2014-01-01

    To investigate the effect of γ-terpineol on cell proliferation and apoptosis of human hepatoma BEL-7402 cells to elucidate its molecular mechanism. Here, BEL-7402 cells were treated with various concentrations (40, 80, 160, 320 and 640 μg/ml) of γ-terpineol for 48 h, cell proliferation was determined by 3-(4,5-dimethyl-thiazolyl-2)-2,5-diphenyl tetrazolium bromides (MTT) assay. Cell colony inhibition was determined by soft agar assay. Apoptosis and possible molecular mechanisms were evaluated by morphological observation, flow cytometry analysis, and DNA fragmentation assay. The γ-terpineol significantly suppressed BEL-7402 cell proliferation in a dose-dependent manner. Characteristic morphological and biochemical changes associated with apoptosis such as cells shrinkage, deformation and vacuolization of mitochondria, nuclear chromatin condensation and fragmentation, formation of apoptotic bodies were observed after BEL-7402 cells treated with γ-terpineol for 24 h and 48 h. Cell cycle were displayed by flow cytometry analysis, the γ-terpineol treatment resulted in accumulation of cells at G₁ or S phase and a blockade of cell proliferation compared to control group. Treating BEL-7402 cells with 320 μg/ml of γ-terpineol for 36 h and 48 h, a typical apoptotic "DNA ladder" was observed using DNA fragmentation assay. The present study demonstrated that possible anti-cancer mechanism of γ-terpineol on human hematomas cells is through inducing cell apoptosis to suppress tumor cell growth.

  15. Indirubin derivatives inhibit Stat3 signaling and induce apoptosis in human cancer cells.

    PubMed

    Nam, Sangkil; Buettner, Ralf; Turkson, James; Kim, Donghwa; Cheng, Jin Q; Muehlbeyer, Stephan; Hippe, Frankie; Vatter, Sandra; Merz, Karl-Heinz; Eisenbrand, Gerhard; Jove, Richard

    2005-04-26

    Stat3 protein has an important role in oncogenesis and is a promising anticancer target. Indirubin, the active component of a traditional Chinese herbal medicine, has been shown previously to inhibit cyclin-dependent kinases, resulting in cell cycle arrest. Here, we show that the indirubin derivatives E564, E728, and E804 potently block constitutive Stat3 signaling in human breast and prostate cancer cells. In addition, E804 directly inhibits Src kinase activity (IC(50) = 0.43 microM) in an in vitro kinase assay. Levels of tyrosyl phosphorylation of c-Src are also reduced in cultured cells 30 min after E804 treatment. Tyrosyl phosphorylation of Stat3, which is known to be phosphorylated by c-Src, was decreased, and constitutive Stat3 DNA binding-activity was suppressed in cells 30 min after E804 treatment. The antiapoptotic proteins Mcl-1 and Survivin, which are encoded in target genes of Stat3, were down-regulated by indirubin derivatives, followed by induction of apoptosis. These results demonstrate that E804 directly blocks the Src-Stat3 signaling pathway, suggesting that the antitumor activity of indirubin compounds is at least partially due to inhibition of this pathway.

  16. Xanthohumol induces generation of reactive oxygen species and triggers apoptosis through inhibition of mitochondrial electron transfer chain complex I.

    PubMed

    Zhang, Bo; Chu, Wei; Wei, Peng; Liu, Ying; Wei, Taotao

    2015-12-01

    Xanthohumol is a prenylflavonoid extracted from hops (Humulus lupulus). It possesses anti-cancer and anti-inflammatory activities in vitro and in vivo, and offers therapeutic benefits for treatment of metabolic syndromes. However, the precise mechanisms underlying its pharmacological effects remain to be elucidated, together with its cellular target. Here, we provide evidence that xanthohumol directly interacts with the mitochondrial electron transfer chain complex I (NADH dehydrogenase), inhibits the oxidative phosphorylation, triggers the production of reactive oxygen species, and induces apoptosis. In addition, we show that as a result of the inhibition of the mitochondrial oxidative phosphorylation, xanthohumol exposure causes a rapid decrease of mitochondrial transmembrane potential. Furthermore, we showed that xanthohumol up-regulates the glycolytic capacity in cells, and thus compensates cellular ATP generation. Dissection of the multiple steps of aerobic respiration by extracellular flux assays revealed that xanthohumol specifically inhibits the activity of mitochondrial complex I, but had little effect on that of complex II, III and IV. Inhibition of complex I by xanthohumol caused the overproduction of reactive oxygen species, which are responsible for the induction of apoptosis in cancer cells. We also found that isoxanthohumol, the structural isomer of xanthohumol, is inactive to cells, suggesting that the reactive 2-hydroxyl group of xanthohumol is crucial for its targeting to the mitochondrial complex I. Together, the remodeling of cell metabolism revealed here has therapeutic potential for the use of xanthohumol.

  17. Core-Scaffold-Inspired Asymmetric Synthesis of Polysubstituted Chiral Hexahydropyridazines that Potently Inhibit Breast Cancer Cell Proliferation by Inducing Apoptosis.

    PubMed

    Leng, Hai-Jun; Peng, Fu; Zingales, Sarah; Huang, Wei; Wang, Biao; Zhao, Qian; Zhou, Rui; He, Gu; Peng, Cheng; Han, Bo

    2015-12-07

    The highly enantioselective preparation of pharmacologically interesting hexahydropyridazine derivatives based on a multicomponent cascade reaction is described. This one-pot approach utilizes an organocatalytic Michael reaction followed by intermolecular α-amination and intramolecular hemiaminalization to yield a chiral pyridazine backbone with contiguous stereogenic centers and multiple functional groups in good yield and with high stereoselectivity. Compounds synthesized by this method potently inhibited proliferation of MCF-7 breast cancer cells. Mechanistic studies suggest that compound 5 c exerts these anticancer effects by inducing apoptosis through extracellular signal related kinase (ERK)- and poly(adenosine diphosphate ribose) polymerase (PARP)-regulated pathways, as well as mitochondrial pathways.

  18. Omega-3 free fatty acids inhibit tamoxifen-induced cell apoptosis.

    PubMed

    Wu, Shufan; Guo, Yang; Wu, Yikuan; Zhu, Shenglong; He, Zhao; Chen, Yong Q

    2015-04-03

    Fish oil, which contains omega-3 fatty acids mainly in the form of triglycerides, has benefits for reducing breast cancer risk, similar to tamoxifen action. However, it remains to be elucidated whether the combination of omega-3 free fatty acid (ω-3FFA) with tamoxifen leads to improved treatment in breast cancer. In this study, we observed that ω-3FFA induces MCF-7 cell apoptosis to suppress cell growth. The treatment of breast cancer cells with ω-3FFA attenuated tamoxifen-induced cell apoptosis. ω-3FFA and tamoxifen significantly increased Erk1/2 and Akt phosphorylation levels in a dose and time dependent manner. Compared to ω-3FFA alone, the combination of tamoxifen with ω-3FFA significantly increased Erk1/2 and Akt phosphorylation levels. Because Erk1/2 and Akt activation has been linked to tamoxifen-related anti-estrogen resistance in breast cancer patients, these results indicate that ω-3FFA may interfere with the effects of tamoxifen in the prevention of breast cancer risk.

  19. ClC-3 deficiency prevents apoptosis induced by angiotensin II in endothelial progenitor cells via inhibition of NADPH oxidase.

    PubMed

    Liu, Jing; Zhang, Fei-Fei; Li, Lei; Yang, Jing; Liu, Jie; Guan, Yong-Yuan; Du, Yan-Hua

    2013-10-01

    Endothelial progenitor cells (EPCs) play an important role in postnatal neovascularization and re-endothelialization in response to tissue ischemia and endothelial injury. It is reported that the circulating EPCs number is decreased during hypertension. However, the detailed mechanism is still unclear. Our previous studies have shown that ClC-3 chloride channel is up-regulated with the development of hypertension. This study aims to test whether ClC-3 participates in EPC apoptosis under the condition of increased oxidative stress in angiotensin II (Ang II)-induced hypertension. The results showed that stimulation with 10(-6)mol/L Ang II significantly up-regulated the endogenous ClC-3 expression and increased intracellular reactive oxygen species (ROS) generation in EPCs of wild type mice, accompanied by an enhanced NADPH oxidase activity and the expression of gp91(phox) (NOX-2), a key catalytic subunit of NADPH oxidase. However, these effects of Ang II were significantly reduced in EPCs of ClC-3(-/-) mice. Compared with control, treatment with Ang II induced EPCs apoptosis in wild type mice, concomitantly with declined Bcl-2/Bax ratio, depressed mitochondrial membrane potential and activation of poly(ADP-ribose) polymerase, which was remarkably prevented by both ClC-3 knockout and NADPH oxidase inhibitor apocynin. In addition, the role of ClC-3 deficiency in protecting EPCs against Ang II-induced oxidative stress and apoptosis was further confirmed in Ang II-infused hypertensive mice in vivo. In conclusion, ClC-3 deficiency inhibited Ang II-induced EPC apoptosis via suppressing ROS generation derived from NADPH oxidase.

  20. Isoliquiritigenin inhibits cell proliferation and induces apoptosis in human hepatoma cells.

    PubMed

    Hsu, Ya-Ling; Kuo, Po-Lin; Lin, Liang-Tzung; Lin, Chun-Ching

    2005-02-01

    Isoliquiritigenin (4,2',4'-trihydroxychalcone, ISL) is a natural pigment with a simple chalcone structure. In this study, we report the ISL-induced inhibition on the growth of human hepatoma cells (Hep G2) for the first time. The cell growth inhibition achieved by ISL treatment resulted in programmed cell death in a caspase activation-dependent manner, with an IC50 of 10.51 microg/mL. Outcomes of ISL treatment included the up-regulation of IkappaBalpha expression in the cytoplasm, and the decrease of NF-kappaB level as well as its activity in the nucleus. In addition, ISL also suppressed the expression of Bcl-XL and c-IAP1/2 protein, the downstream target molecule of NF-kappaB. These results demonstrated that ISL treatment inhibited the NF-kappaB cell survival-signaling pathway and induced apoptotic cell death in Hep G2 cells.

  1. Inhibition of autophagy enhances DNA damage-induced apoptosis by disrupting CHK1-dependent S phase arrest

    SciTech Connect

    Liou, Jong-Shian; Wu, Yi-Chen; Yen, Wen-Yen; Tang, Yu-Shuan; Kakadiya, Rajesh B.; Su, Tsann-Long; Yih, Ling-Huei

    2014-08-01

    DNA damage has been shown to induce autophagy, but the role of autophagy in the DNA damage response and cell fate is not fully understood. BO-1012, a bifunctional alkylating derivative of 3a-aza-cyclopenta[a]indene, is a potent DNA interstrand cross-linking agent with anticancer activity. In this study, BO-1012 was found to reduce DNA synthesis, inhibit S phase progression, and induce phosphorylation of histone H2AX on serine 139 (γH2AX) exclusively in S phase cells. Both CHK1 and CHK2 were phosphorylated in response to BO-1012 treatment, but only depletion of CHK1, but not CHK2, impaired BO-1012-induced S phase arrest and facilitated the entry of γH2AX-positive cells into G2 phase. CHK1 depletion also significantly enhanced BO-1012-induced cell death and apoptosis. These results indicate that BO-1012-induced S phase arrest is a CHK1-dependent pro-survival response. BO-1012 also resulted in marked induction of acidic vesicular organelle (AVO) formation and microtubule-associated protein 1 light chain 3 (LC3) processing and redistribution, features characteristic of autophagy. Depletion of ATG7 or co-treatment of cells with BO-1012 and either 3-methyladenine or bafilomycin A1, two inhibitors of autophagy, not only reduced CHK1 phosphorylation and disrupted S phase arrest, but also increased cleavage of caspase-9 and PARP, and cell death. These results suggest that cells initiate S phase arrest and autophagy as pro-survival responses to BO-1012-induced DNA damage, and that suppression of autophagy enhances BO-1012-induced apoptosis via disruption of CHK1-dependent S phase arrest. - Highlights: • Autophagy inhibitors enhanced the cytotoxicity of a DNA alkylating agent, BO-1012. • BO-1012-induced S phase arrest was a CHK1-dependent pro-survival response. • Autophagy inhibition enhanced BO-1012 cytotoxicity via disrupting the S phase arrest.

  2. Antioxidants inhibit advanced glycosylation end-product-induced apoptosis by downregulation of miR-223 in human adipose tissue-derived stem cells

    PubMed Central

    Wang, Zhe; Li, Hongqiu; Guo, Ran; Wang, Qiushi; Zhang, Dianbao

    2016-01-01

    Advanced glycosylation end products (AGEs) are endogenous inflammatory mediators that induce apoptosis of mesenchymal stem cells. A potential mechanism includes increased generation of reactive oxygen species (ROS). MicroRNA-223 (miR-223) is implicated in the regulation of cell growth and apoptosis in several cell types. Here, we tested the hypothesis that antioxidants N-acetylcysteine (NAC) and ascorbic acid 2-phosphate (AAP) inhibit AGE-induced apoptosis via a microRNA-dependent mechanism in human adipose tissue-derived stem cells (ADSCs). Results showed that AGE-HSA enhanced apoptosis and caspase-3 activity in ADSCs. AGE-HSA also increased ROS generation and upregulated the expression of miR-223. Interestingly, reductions in ROS generation and apoptosis, and upregulation of miR-223 were found in ADSCs treated with antioxidants NAC and AAP. Furthermore, miR-223 mimics blocked antioxidant inhibition of AGE-induced apoptosis and ROS generation. Knockdown of miR-223 amplified the protective effects of antioxidants on apoptosis induced by AGE-HSA. miR-223 acted by targeting fibroblast growth factor receptor 2. These results indicate that NAC and AAP suppress AGE-HSA-induced apoptosis of ADSCs, possibly through downregulation of miR-223. PMID:26964642

  3. Polyphenols isolated from Allium cepa L. induces apoptosis by suppressing IAP-1 through inhibiting PI3K/Akt signaling pathways in human leukemic cells.

    PubMed

    Han, Min Ho; Lee, Won Sup; Jung, Ji Hyun; Jeong, Jae-Hun; Park, Cheol; Kim, Hye Jung; Kim, GonSup; Jung, Jin-Myung; Kwon, Taeg Kyu; Kim, Gi-Young; Ryu, Chung Ho; Shin, Sung Chul; Hong, Soon Chan; Choi, Yung Hyun

    2013-12-01

    Allium cepa Linn is commonly used as supplementary folk remedy for cancer therapy. Evidence suggests that Allium extracts have anti-cancer properties. However, the mechanisms of the anti-cancer activity of A. cepa Linn are not fully elucidated in human cancer cells. In this study, we investigated anti-cancer effects of polyphenols extracted from lyophilized A. cepa Linn (PEAL) in human leukemia cells and their mechanisms. PEAL inhibited cancer cell growth by inducing caspase-dependent apoptosis. The apoptosis was suppressed by caspase 8 and 9 inhibitors. PEAL also up-regulated TNF-related apoptosis-inducing ligand (TRAIL) receptor DR5 and down-regulated survivin and cellular inhibitor of apoptosis 1 (cIAP-1). We confirmed these findings in other leukemic cells (THP-1, K562 cells). In addition, PEAL suppressed Akt activity and the PEAL-induced apoptosis was significantly attenuated in Akt-overexpressing U937 cells. In conclusion, our data suggested that PEAL induced caspase-dependent apoptosis in several human leukemic cells including U937 cells. The apoptosis was triggered through extrinsic pathway by up-regulating DR5 modulating as well as through intrinsic pathway by modulating IAP family members. In addition, PEAL induces caspase-dependent apoptosis at least in part through the inhibition of phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway. This study provides evidence that PEAL might be useful for the treatment of leukemia.

  4. Solanum tuberosum lectin inhibits Ehrlich ascites carcinoma cells growth by inducing apoptosis and G2/M cell cycle arrest.

    PubMed

    Kabir, Syed Rashel; Rahman, Md Musfikur; Amin, Ruhul; Karim, Md Rezaul; Mahmud, Zahid Hayat; Hossain, M Tofazzal

    2016-06-01

    Recently, a lectin was purified from the potato cultivated in Bangladesh locally known as Sheel. In the present study cytotoxicity of the lectin against Ehrlich ascites carcinoma (EAC) cells was studied by MTT assay in vitro in RPMI-1640 medium and 8.0-36.0 % cell growth inhibition was observed at the range of 2.5-160 μg/ml protein concentration when incubated for 24 h. The lectin-induced apoptosis in EAC cells was confirmed by fluorescence and optical microscope. The apoptotic cell death was also confirmed by using caspase inhibitors. Cells growth inhibition caused by the lectin (36 %) was remarkably decreased to 7.6 and 22.3 % respectively in the presence of caspase-3 and -8 inhibitors. RT-PCR was used to evaluate the expression of apoptosis-related genes Bcl-X, p53, and Bax. An intensive expression of Bcl-X gene was observed in untreated control EAC cells with the disappeared of the gene in Sheel-treated EAC cells. At the same time, Bax gene expression appeared only in Sheel-treated EAC cells and the expression level of the p53 gene was increased remarkable after the treatment of EAC cells with the lectin. The lectin showed strong agglutination activity against EAC cells. Flow cytometry was used to study the cell cycle phases of EAC cells and it was observed that the lectin arrested the G2/M phase. In conclusion, Sheel lectin inhibited EAC cells growth by inducing apoptosis.

  5. SOD/catalase mimetic platinum nanoparticles inhibit heat-induced apoptosis in human lymphoma U937 and HH cells.

    PubMed

    Yoshihisa, Yoko; Zhao, Qing-Li; Hassan, Mariame Ali; Wei, Zhang-Li; Furuichi, Megumi; Miyamoto, Yusei; Kondo, Takashi; Shimizu, Tadamichi

    2011-03-01

    Platinum nanoparticles (Pt-NPs) are known to possess anti-tumouric activity and the ability to scavenge superoxides and peroxides indicating that they can act as superoxide dismutase (SOD)/catalase mimetics. These potentials seem useful in the protection and/or amelioration of oxidative stress-associated pathologies, but, when they are combined with a therapeutic modality that depends upon the mediation of reactive oxygen species in cell killing induction, the effect of Pt-NPs might be questionable. Here, the effects of polyacrylic acid-capped Pt-NPs (nano-Pts) on hyperthermia (HT)-induced apoptosis and the underlying molecular mechanisms were investigated in human myelomonocytic lymphoma U937 and human cutaneous T-cell lymphoma HH cells. The results showed that the pre-treatment with nano-Pts significantly inhibited HT-induced apoptosis in a dose-dependent manner. Superoxide, but not peroxides, was suppressed to varying extents. All pathways involved in apoptosis execution were also negatively affected. The results reveal that the combination of nano-Pts and HT could result in HT-desensitization.

  6. α-Lipoic acid inhibits sevoflurane-induced neuronal apoptosis through PI3K/Akt signalling pathway.

    PubMed

    Ma, Rong; Wang, Xiang; Peng, Peipei; Xiong, Jingwei; Dong, Hongquan; Wang, Lixia; Ding, Zhengnian

    2016-01-01

    Sevoflurane is a widely used anaesthetic agent, including in anaesthesia of children and infants. Recent studies indicated that the general anaesthesia might cause the cell apoptosis in the brain. This issue raises the concerns about the neuronal toxicity induced by the application of anaesthetic agents, especially in the infants and young children. In this study, we used Morris water maze, western blotting and immunohistochemistry to elucidate the role of α-lipoic acid in the inhibition of neuronal apoptosis. We found that sevoflurane led to the long-term cognitive impairment in the young rats. This adverse effect may be caused by the neuronal death in the hippocampal region, mediated through PI3K/Akt signalling pathway. We also showed that α-lipoic acid offset the effect of sevoflurane on the neuronal apoptosis and cognitive dysfunction. This study elucidated the potential clinical role of α-lipoic acid, providing a promising way in the prevention and treatment of long-term cognitive impairment induced by sevoflurane general anesthesia.

  7. Nef induces apoptosis by activating JNK signaling pathway and inhibits NF-kappaB-dependent immune responses in Drosophila.

    PubMed

    Lee, Sung Bae; Park, Jeehye; Jung, Jae U; Chung, Jongkyeong

    2005-05-01

    The human immunodeficiency virus type 1 (HIV-1) nef gene encodes a 27-kDa protein that plays a crucial role during AIDS pathogenesis, but its exact functional mechanism has not been fully elucidated and remains controversial. The present study illuminated the in vivo functions of Nef using Drosophila, in which genetic analyses can be conveniently conducted. Using Drosophila transgenic lines for wild-type Nef, we demonstrated that Nef is not involved in the regulation of cell proliferation but rather specifically induces caspase-dependent apoptosis in wings in a cell-autonomous manner. Interestingly, myristoylation-defective Nef completely failed to induce the apoptotic wing phenotypes, consistent with previous reports demonstrating a crucial role for membrane localization of Nef in vivo. Further genetic and immunohistochemical studies revealed that Nef-dependent JNK activation is responsible for apoptosis. Furthermore, we found that ectopic expression of Nef inhibits Drosophila innate immune responses including Relish NF-kappaB activation with subsequent induction of an antimicrobial peptide, diptericin. The in vivo functions of Nef in Drosophila are highly consistent with those found in mammals and so we propose that Nef regulates evolutionarily highly conserved signaling molecules of the JNK and NF-kappaB signaling pathways at the plasma membrane, and consequently modulates apoptosis and immune responses in HIV target cells.

  8. CR108, a novel vitamin K3 derivative induces apoptosis and breast tumor inhibition by reactive oxygen species and mitochondrial dysfunction

    SciTech Connect

    Yang, Chun-Ru; Liao, Wei-Siang; Wu, Ya-Hui; Murugan, Kaliyappan; Chen, Chinpiao; Chao, Jui-I

    2013-12-15

    Vitamin K3 derivatives have been shown to exert anticancer activities. Here we show a novel vitamin K3 derivative (S)-2-(2-hydroxy-3-methylbutylthio)naphthalene-1,4-dione, which is named as CR108 that induces apoptosis and tumor inhibition through reactive oxygen species (ROS) and mitochondrial dysfunction in human breast cancer. CR108 is more effective on the breast cancer cell death than other vitamin K3 derivatives. Moreover, CR108 induced apoptosis in both the non-HER-2-overexpressed MCF-7 and HER-2-overexpressed BT-474 breast cancer cells. CR108 caused the loss of mitochondrial membrane potential, cytochrome c released from mitochondria to cytosol, and cleaved PARP proteins for apoptosis induction. CR108 markedly increased ROS levels in breast cancer cells. N-acetylcysteine (NAC), a general ROS scavenger, completely blocked the CR108-induced ROS levels, mitochondrial dysfunction and apoptosis. Interestingly, CR108 increased the phosphorylation of p38 MAP kinase but conversely inhibited the survivin protein expression. NAC treatment prevented the activation of p38 MAP kinase and rescued the survivin protein levels. SB202190, a specific p38 MAP kinase inhibitor, recovered the survivin protein levels and attenuated the cytotoxicity of CR108-treated cells. Furthermore, CR108 inhibited the xenografted human breast tumor growth in nude mice. Together, we demonstrate that CR108 is a novel vitamin K3 derivative that induces apoptosis and tumor inhibition by ROS production and mitochondrial dysfunction and associates with the phosphorylation of p38 MAP kinase and the inhibition of survivin in the human breast cancer. - Highlights: • CR108 is more effective on the cell death than other vitamin K3 derivatives. • CR108 induces apoptosis and tumor inhibition by ROS and mitochondrial dysfunction. • CR108 induces apoptosis by p38 kinase activation and survivin inhibition. • CR108 is a potent vitamin K3 analog that can develop for breast cancer therapy.

  9. Inhibition of NF-κB by deoxycholic acid induces miR-21/PDCD4-dependent hepatocelular apoptosis.

    PubMed

    M Rodrigues, Pedro; B Afonso, Marta; L Simão, André; M Borralho, Pedro; M P Rodrigues, Cecília; E Castro, Rui

    2015-12-01

    MicroRNAs (miRNAs/miRs) are key regulators of liver metabolism, while toxic bile acids participate in the development of several liver diseases. We previously demonstrated that deoxycholic acid (DCA), a cytotoxic bile acid implicated in the pathogenesis of non-alcoholic fatty liver disease, inhibits miR-21 expression in hepatocytes. Here, we investigated the mechanisms by which DCA modulates miR-21 and whether miR-21 contributes for DCA-induced cytotoxicity. DCA inhibited miR-21 expression in primary rat hepatocytes in a dose-dependent manner, and increased miR-21 pro-apoptotic target programmed cell death 4 (PDCD4) and apoptosis. Both miR-21 overexpression and PDCD4 silencing hampered DCA-induced cell death. Further, DCA decreased NF-κB activity, shown to represent an upstream mechanism leading to modulation of the miR-21/PDCD4 pathway. In fact, NF-κB overexpression or constitutive activation halted miR-21-dependent apoptosis by DCA while opposite results were observed upon NF-κB inhibition. In turn, DCA-induced oxidative stress resulted in caspase-2 activation and NF-κB/miR-21 inhibition, in a PIDD-dependent manner. Finally, modulation of the NF-κB/miR-21/PDCD4 pro-apoptotic pathway by DCA was also shown to occur in the rat liver in vivo. These signalling circuits may constitute appealing targets for bile acid-associated liver pathologies.

  10. Spirooxindole derivative SOID-8 induces apoptosis associated with inhibition of JAK2/STAT3 signaling in melanoma cells.

    PubMed

    Tian, Yan; Nam, Sangkil; Liu, Lucy; Yakushijin, Fumiko; Yakushijin, Kenichi; Buettner, Ralf; Liang, Wei; Yang, Fan; Ma, Yuelong; Horne, David; Jove, Richard

    2012-01-01

    Melanoma is generally refractory to current chemotherapy, thus new treatment strategies are needed. In this study, we synthesized a series of spirooxindole derivatives (SOID-1 to SOID-12) and evaluated their antitumor effects on melanoma. Among the 12 spirooxindole derivatives, SOID-8 showed the strongest antitumor activity by viability screening. SOID-8 inhibited viability of A2058, A375, SK-MEL-5 and SK-MEL-28 human melanoma cells in a dose- and time-dependent manner. SOID-8 also induced apoptosis of these tumor cells, which was confirmed by positive Annexin V staining and an increase of poly(ADP-ribose) polymerase cleavage. The antiapoptotic protein Mcl-1, a member of the Bcl-2 family, was downregulated and correlated with SOID-8 induced apoptosis. In addition, SOID-8 reduced tyrosine phosphorylation of Signal Tansducer and Activator of Transcription 3 (STAT3) in both dose- and time-dependent manners. This inhibition was associated with decreased levels of phosphorylation of Janus-activated kinase-2 (JAK2), an upstream kinase that mediates STAT3 phosphorylation at Tyr705. Accordingly, SOID-8 inhibited IL-6-induced activation of STAT3 and JAK2 in melanoma cells. Finally, SOID-8 suppressed melanoma tumor growth in a mouse xenograft model, accompanied with a decrease of phosphorylation of JAK2 and STAT3. Our results indicate that the antitumor activity of SOID-8 is at least partially due to inhibition of JAK2/STAT3 signaling in melanoma cells. These findings suggest that the spirooxindole derivative SOID-8 is a promising lead compound for further development of new preventive and therapeutic agents for melanoma.

  11. Reducing Smad3/ATF4 was essential for Sirt1 inhibiting ER stress-induced apoptosis in mice brown adipose tissue.

    PubMed

    Liu, Zhenjiang; Gu, Huihui; Gan, Lu; Xu, Yatao; Feng, Fei; Saeed, Muhammad; Sun, Chao

    2017-02-07

    Sirtuin 1 (Sirt1) promotes adaptive thermogenesis by controlling the acetylation status of enzymes and transcriptional factors in interscapular brown adipose tissue (iBAT). However, the effects of Sirt1 on endoplasmic reticulum (ER) stress and apoptosis of iBAT remain elusive. In this study, the mRNA levels of Sirt1 and thermogenesis genes were reduced but the genes related with ER stress were elevated in iBAT of high-fat diet (HFD)-induced obese mice. Moreover, ER stress further inhibited mRNA level of Sirt1 and triggered brown adipocyte apoptosis in vitro and in vivo. Further analysis revealed that Sirt1 overexpression alleviated ER stress-induced brown adipocyte apoptosis by inhibiting Smad3 and ATF4. In addition, Smad3 bound to ATF4 promoter region and positively transcriptional regulation of ATF4. Our data also confirmed that Sirt1 reduced early apoptotic cells and blocked the mitochondrial apoptosis pathway by directly interacting with ATF4. Furthermore, Sirt1 attenuated tunicamycin-induced cold intolerance and elevating thermogenesis by inhibiting ER stress and apoptosis in iBAT. In summary, our data collectively revealed Sirt1 reduced ER stress and apoptosis of brown adipocyte in vivo and in vitro by inhibiting Smad3/ATF4 signal. These data reveal a novel mechanism that links Sirt1 to brown adipocyte apoptosis.

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

    PubMed

    Jalali, Fatemeh; Sharifi, Mohammadreza; Salehi, Rasoul

    2016-01-01

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

  13. MicroRNA-219-5p Inhibits Morphine-Induced Apoptosis by Targeting Key Cell Cycle Regulator WEE1.

    PubMed

    Lou, Wei; Zhang, Xingwang; Hu, Xiao-Ying; Hu, Ai-Rong

    2016-06-02

    BACKGROUND To identify the effects of microRNA (miR)-219-5p on morphine-induced apoptosis by targeting WEE1. MATERIAL AND METHODS Forty Balb/C mice (Toll-like receptor 9, TLR9 knockout) were randomly allocated to the experimental and control groups (20 in each group). The baseline miR-219-5p expression was detected using quantitative real-time PCR (qRT-PCR). After morphine was injected at 6 h on the 2nd and 6th days, experimental and control groups received miR-219-5p mimics or miRNA-negative control (NC), respectively, compound injection. Tissues and cells were later obtained from subjects in each group separately after mice were killed. TUNEL assay was used to investigate apoptosis in both groups. RAW264.7 cells were treated with miR-219-5p mimics and controls, respectively. After 24 h, 10 μM of morphine was added at 24 h. Cell apoptosis was assessed by flow cytometer. The WEE1 and Phospho-cdc2 (Tyr15) expressions were examined by Western blotting. RESULTS MiR-219-5p expression in the experimental group was significantly lower than that in the control group (P<0.05). Mice injected with miR-219-5p mimic experienced an evident increase in apoptosis rate compared with the control group (P<0.05). The miR-219-5p NC group and the morphine group both presented an elevated apoptosis rate compared with the blank control group (both, P<0.05). The apoptosis rate in the miR-219-5p mimic group was 10.06%, remarkably lower than in the miR-219-5p NC group and blank control group (both P<0.05). WEE1 and Tyr15 protein expressions in the miR-219-5p NC group and morphine group were obviously stronger than those in the blank control group (all P<0.05). In the miR-219-5p mimic group, WEE1 and Tyr15 protein expressions were significantly lower compared with those in the miR-219-5p NC group and morphine group (all P<0.05). CONCLUSIONS Morphine significantly downregulated the expression of miRNA-219-5p, which targets WEE1 to suppress Tyr15 expressions and activate Cdc2, thus inhibiting

  14. Sesquiterpene lactones derived from Saussurea lappa induce apoptosis and inhibit invasion and migration in neuroblastoma cells.

    PubMed

    Tabata, Keiichi; Nishimura, Yuki; Takeda, Taiji; Kurita, Masahiro; Uchiyama, Taketo; Suzuki, Takashi

    2015-04-01

    Neuroblastoma is among the most fatal of solid tumors in the pediatric age group, even when treated aggressively. Therefore, a new effective therapeutic drug(s) for neuroblastoma is urgently needed. To clarify the anticancer effects of the sesquiterpene lactones dehydrocostus lactone and costunolide, derived from Saussurea lappa, we examined the cytotoxic and migration/invasion-inhibitory effects of these compounds against neuroblastoma cell lines. Both the compounds exerted significant cytotoxicity against the neuroblastoma cell lines IMR-32, NB-39, SK-N-SH, and LA-N-1. Evidence of cellular apoptosis, such as nuclear condensation and membrane inversion, were observed after treatment with these compounds. Both compounds induced caspase-7 activation and PARP cleavage as confirmed by Western blotting. Furthermore, the sesquiterpene lactones also suppressed invasion and migration of the neuroblastoma cells. These results suggest that dehydrocostus lactone and costunolide are promising candidates for being developed into novel anticancer drugs effective against neuroblastoma.

  15. Doxycycline inhibits proliferation and induces apoptosis of both human papillomavirus positive and negative cervical cancer cell lines.

    PubMed

    Zhao, Yan; Wang, Xinyu; Li, Lei; Li, Changzhong

    2016-05-01

    The clinical management of cervical cancer remains a challenge and the development of new treatment strategies merits attention. However, the discovery and development of novel compounds can be a long and labourious process. Drug repositioning may circumvent this process and facilitate the rapid translation of hypothesis-driven science into the clinics. In this work, we show that a FDA-approved antibiotic, doxycycline, effectively targets human papillomavirus (HPV) positive and negative cervical cancer cells in vitro and in vivo. Doxycycline significantly inhibits proliferation of a panel of cervical cancer cell lines. It also induces apoptosis of cervical cancer cells in a time- and dose-dependent manner. In addition, the apoptosis induced by doxycycline is through caspase-dependent pathway. Mechanism studies demonstrate that doxycycline affects oxygen consumption rate, glycolysis, and reduces ATP levels in cervical cancer cells. In HeLa xenograft mouse model, doxycycline significantly inhibits growth of tumour. Our in vitro and in vivo data clearly demonstrate the inhibitory effects of doxycycline on the growth and survival of cervical cancer cells. Our work provides the evidence that doxycycline can be repurposed for the treatment of cervical cancer and targeting energy metabolism may represent a potential therapeutic strategy for cervical cancer.

  16. A Pyrazolo[3,4-d]pyrimidine compound inhibits Fyn phosphorylation and induces apoptosis in natural killer cell leukemia

    PubMed Central

    Laurenzana, Ilaria; Caivano, Antonella; Trino, Stefania; De Luca, Luciana; Rocca, Francesco La; Simeon, Vittorio; Tintori, Cristina; D'Alessio, Francesca; Teramo, Antonella; Zambello, Renato; Traficante, Antonio; Maietti, Maddalena; Semenzato, Gianpietro; Schenone, Silvia; Botta, Maurizio

    2016-01-01

    Natural killer (NK) cell neoplasms are characterized by clonal proliferation of cytotoxic NK cells. Since there is no standard treatment to date, new therapeutic options are needed, especially for NK aggressive tumors. Fyn tyrosine kinase has a key role in different biological processes, such as cell growth and differentiation, being also involved in the pathogenesis of hematologic malignancies. Our previous studies led us to identify 4c pyrazolo[3,4-d]pyrimidine compound capable of inhibiting Fyn activation and inducing apoptosis in different cancer cell lines. Here we investigated the presence of Fyn and the effect of its inhibitor in NK malignant cells. Firstly, we showed Fyn over-expression in NK leukemic cells compared to peripheral blood mononuclear cells from healthy donors. Subsequently, we demonstrated that 4c treatment reduced cell viability, induced caspase 3-mediate apoptosis and cell cycle arrest in NK cells. Moreover, by inhibiting Fyn phosphorylation, 4c compound reduced Akt and P70 S6 kinase activation and changed the expression of genes involved in cell death and survival in NK cells. Our study demonstrated that Fyn is involved in the pathogenesis of NK leukemia and that it could represent a potential target for this neoplasm. Moreover, we proved that Fyn inhibitor pyrazolo[3,4-d]pyrimidine compound, could be a started point to develop new therapeutic agents. PMID:27566560

  17. Inhibition of miR-155 Protects Against LPS-induced Cardiac Dysfunction and Apoptosis in Mice

    PubMed Central

    Wang, Hui; Bei, Yihua; Huang, Peipei; Zhou, Qiulian; Shi, Jing; Sun, Qi; Zhong, Jiuchang; Li, Xinli; Kong, Xiangqing; Xiao, Junjie

    2016-01-01

    Sepsis-induced myocardial dysfunction represents a major cause of death in intensive care units. Dysregulated microRNAs (miR)-155 has been implicated in multiple cardiovascular diseases and miR-155 can be induced by lipopolysaccharide (LPS). However, the role of miR-155 in LPS-induced cardiac dysfunction is unclear. Septic cardiac dysfunction in mice was induced by intraperitoneal injection of LPS (5 mg/kg) and miR-155 was found to be significantly increased in heart challenged with LPS. Pharmacological inhibition of miR-155 using antagomiR improved cardiac function and suppressed cardiac apoptosis induced by LPS in mice as determined by echocardiography, terminal deoxynucleotidyl transferase nick-end labeling (TUNEL) assay, and Western blot for Bax and Bcl-2, while overexpression of miR-155 using agomiR had inverse effects. Pea15a was identified as a target gene of miR-155, mediating its effects in controlling apoptosis of cardiomyocytes as evidenced by luciferase reporter assays, quantitative real time-polymerase chain reaction, Western blot, and TUNEL staining. Noteworthy, miR-155 was also found to be upregulated in the plasma of patients with septic cardiac dysfunction compared to sepsis patients without cardiac dysfunction, indicating a potential clinical relevance of miR-155. The receiver-operator characteristic curve indicated that plasma miR-155 might be a biomarker for sepsis patients developing cardiac dysfunction. Therefore, inhibition of miR-155 represents a novel therapy for septic myocardial dysfunction. PMID:27727247

  18. Cycloartenyl Ferulate Inhibits Paraquat-Induced Apoptosis in HK-2 Cells With the Involvement of ABCC1.

    PubMed

    Hong, Guang-Liang; Liu, Jia-Ming; Zhao, Guang-Ju; Tan, Jia-Ping; Wu, Bin; Li, Meng-Fang; Liang, Guang; Qiu, Qiao-Meng; Lu, Zhong-Qiu

    2016-04-01

    Nephrotoxicity induced by chemicals such as paraquat (PQ) is a common clinical phenomenon; therefore, searching for drugs with renal protective effect is of a great practical significance. Our previous investigation found that cycloartenyl ferulate (CF) can antagonize the cytotoxic effect of PQ, and recent studies also revealed a variety of bioactivities of CF. However, specific molecular mechanisms underlying the protective effect of CF have not been explored yet. HPLC detection of PQ content indicated that CF reduced PQ accumulation in HK-2 cells and thereby improved cell survival. Western blot results showed that both PQ and CF did not affect the expression of ABCB1; however, while PQ suppressed the expression of ABCC1, CF upregulated ABCC1 expression and thereby reversed the inhibitory effect of PQ on ABCC1 expression. Meanwhile, HK-2 cells did not express ABCG2. When the expression of ABCC1 was knocked down with siRNA, the inhibitory effect of CF on intracellular PQ accumulation was blocked. Further flow cytometric analysis showed that while PQ significantly induced the appearance of sub-G1 apoptotic peak in cells, CF evidently inhibited apoptosis. TUNEL-DAPI double-staining also detected that PQ significantly induced the occurrence of DNA fragmentation in cells, whereas CF effectively inhibited the effect of PQ. Further results showed that ABCC1 siRNA effectively abolished the protective effect of CF on PQ-induced apoptosis. Taken together, these data demonstrated that in HK-2 cells, CF could antagonize PQ-induced toxicity with the involvement of regulatiion of ABCC1 protein expression, which provides a new strategy for treatments of nephrotoxicity.

  19. The Pan-Aurora Kinase Inhibitor, PHA-739358, Induces Apoptosis and Inhibits Migration in Melanoma Cell Lines

    PubMed Central

    Xie, Lifang; Meyskens, Frank L

    2014-01-01

    Treatment of metastatic melanoma has long been a challenge due to its resistance to traditional chemotherapeutics leading to the search for alternative strategies. Aurora kinases are key mitotic regulators that are frequently overexpressed in various cancers including melanoma, making them ideal targets for anticancer therapeutics. Several Aurora kinase inhibitors have been developed and tested pre-clinically and clinically. PHA-739358 is currently the most advanced clinical compound; however its antitumor effect has not been tested in melanoma. In this study, the anti-proliferative and anti-invasive effects of PHA-739358 were investigated in melanoma cell lines. The results demonstrated that PHA-739358 produces a time and dose dependent inhibition of cell proliferation, induction of apoptosis, and inhibition of cell migration. Downregulation of MMP-2 via inhibition of NFκB signaling pathway may contribute to PHA-739358-induced migration inhibition. Furthermore, PHA-739358 enhanced temozolomide-induced caspase activation. This study provides a promising new strategy for the treatment of advanced melanoma. PMID:23344158

  20. Inhibition of MEK5 by BIX02188 induces apoptosis in cells expressing the oncogenic mutant FLT3-ITD

    SciTech Connect

    Razumovskaya, Elena; Sun, Jianmin; Roennstrand, Lars

    2011-08-26

    Highlights: {yields} In this study we have demonstrated that FLT3 activation leads to activation of ERK5. {yields} We have demonstrated that ERK5 is involved in activation of AKT downstream of FLT3. {yields} (BIX02188) blocks activation of ERK5 and induces apoptosis in FLT3 Ba/F3 cells. {yields} (BIX02188) induce apoptosis in the two leukemic cell lines MV4-11 and MOLM-13. -- Abstract: Fms-like tyrosine kinase-3 (FLT3) is a growth factor receptor normally expressed on hematopoietic progenitor cells. Approximately one third of all patients with AML carry an activating mutation in FLT3 that drives proliferation and survival of the leukemic cells. The most common activating mutation is the so-called internal tandem duplication (ITD), which involves an in-frame duplication of a segment of varying length in the region of the FLT3 gene that encodes the juxtamembrane domain. The pathways downstream of FLT3-ITD are partially known but further knowledge regarding the downstream signal transduction molecules is important in order to develop alternative strategies for pharmacological intervention. In this paper we have studied the role of MEK/ERK5 in FLT3-ITD mediated transformation. We have found that both wild-type FLT3 and FLT3-ITD activate MEK5 leading to the activation of ERK5. By use of the selective inhibitor of MEK5, (BIX02188), we have shown that activation of AKT downstream of FLT3 is partially dependent on ERK5. Furthermore, inhibition of MEK5/ERK5 induces apoptosis of both FLT3-ITD transfected Ba/F3 cells as well as the FLT3-ITD carrying leukemic cell lines MV4-11 and MOLM-13. These results suggest that MEK5/ERK5 is important for FLT3-ITD induced hematopoietic transformation and may thus represent an alternative therapeutic target in the treatment of FLT3-ITD positive leukemia.

  1. Suppression of osteopontin inhibits chemically induced hepatic carcinogenesis by induction of apoptosis in mice

    PubMed Central

    Lee, Su-Hyung; Park, Jun-Won; Woo, Sang-Ho; Go, Du-Min; Kwon, Hyo-Jung; Jang, Ja-June; Kim, Dae-Yong

    2016-01-01

    Previous clinical reports have found elevated osteopontin (OPN) levels in tumor tissues to be indicative of greater malignancy in human hepatocellular carcinoma (HCC). However, the role of OPN on carcinogenesis and its underlying mechanism remain unclear. In the present study, we investigated the oncogenic role of OPN in diethylnitrosamine (DEN)-induced hepatic carcinogenesis in mice. The overall incidence of hepatic tumors at 36 weeks was significantly lower in OPN knockout (KO) mice than in wild-type (WT) mice. Apoptosis was significantly enhanced in OPN KO mice, and was accompanied by the downregulation of epidermal growth factor receptor (EGFR). In the in vitro study, OPN suppression also led to lower mRNA and protein levels of EGFR associated with the downregulation of c-Jun in Hep3B and Huh7 human HCC cells lines, which resulted in increased apoptotic cell death in both cell lines. Moreover, a positive correlation was clearly identified between the expression of OPN and EGFR in human HCC tissues. These data demonstrate that the OPN deficiency reduced the incidence of chemically induced HCC by suppressing EGFR-mediated anti-apoptotic signaling. An important implication of our findings is that OPN positively contributes to hepatic carcinogenesis. PMID:27888617

  2. 3-Bromopyruvate inhibits cell proliferation and induces apoptosis in CD133+ population in human glioma.

    PubMed

    Xu, Dong-Qiang; Tan, Xiao-Yu; Zhang, Bao-Wei; Wu, Tao; Liu, Ping; Sun, Shao-Jun; Cao, Yin-Guang

    2016-03-01

    The study was aimed to investigate the role of 3-bromopyruvate in inhibition of CD133+ U87 human glioma cell population growth. The results demonstrated that 3-bromopyruvate inhibited the viability of both CD133+ and parental cells derived from U87 human glioma cell line. However, the 3-bromopyruvate-induced inhibition in viability was more prominent in CD133+ cells at 10 μM concentration after 48 h. Treatment of CD133+ cells with 3-bromopyruvate caused reduction in cell population and cell size, membrane bubbling, and degradation of cell membranes. Hoechst 33258 staining showed condensation of chromatin material and fragmentation of DNA in treated CD133+ cells after 48 h. 3-Bromopyruvate inhibited the migration rate of CD133+ cells significantly compared to the parental cells. Flow cytometry revealed that exposure of CD133+ cells to 3-bromopyruvate increased the cell population in S phase from 24.5 to 37.9 % with increase in time from 12 to 48 h. In addition, 3-bromopyruvate significantly enhanced the expression of Bax and cleaved caspase 3 in CD133+ cells compared to the parental cells. Therefore, 3-bromopyruvate is a potent chemotherapeutic agent for the treatment of glioma by targeting stem cells selectively.

  3. Inhibition of autophagy enhances DNA damage-induced apoptosis by disrupting CHK1-dependent S phase arrest.

    PubMed

    Liou, Jong-Shian; Wu, Yi-Chen; Yen, Wen-Yen; Tang, Yu-Shuan; Kakadiya, Rajesh B; Su, Tsann-Long; Yih, Ling-Huei

    2014-08-01

    DNA damage has been shown to induce autophagy, but the role of autophagy in the DNA damage response and cell fate is not fully understood. BO-1012, a bifunctional alkylating derivative of 3a-aza-cyclopenta[a]indene, is a potent DNA interstrand cross-linking agent with anticancer activity. In this study, BO-1012 was found to reduce DNA synthesis, inhibit S phase progression, and induce phosphorylation of histone H2AX on serine 139 (γH2AX) exclusively in S phase cells. Both CHK1 and CHK2 were phosphorylated in response to BO-1012 treatment, but only depletion of CHK1, but not CHK2, impaired BO-1012-induced S phase arrest and facilitated the entry of γH2AX-positive cells into G2 phase. CHK1 depletion also significantly enhanced BO-1012-induced cell death and apoptosis. These results indicate that BO-1012-induced S phase arrest is a CHK1-dependent pro-survival response. BO-1012 also resulted in marked induction of acidic vesicular organelle (AVO) formation and microtubule-associated protein 1 light chain 3 (LC3) processing and redistribution, features characteristic of autophagy. Depletion of ATG7 or co-treatment of cells with BO-1012 and either 3-methyladenine or bafilomycin A1, two inhibitors of autophagy, not only reduced CHK1 phosphorylation and disrupted S phase arrest, but also increased cleavage of caspase-9 and PARP, and cell death. These results suggest that cells initiate S phase arrest and autophagy as pro-survival responses to BO-1012-induced DNA damage, and that suppression of autophagy enhances BO-1012-induced apoptosis via disruption of CHK1-dependent S phase arrest.

  4. Autophagy inhibition and mitochondrial remodeling join forces to amplify apoptosis in activation-induced cell death.

    PubMed

    Mauro, Corrado; Silvia, Campello

    2016-12-01

    Mitochondrial structural and functional changes and the autophagy pathway crosstalk under several stress conditions. However, their interplay under physiological cell death stimulation has been unclear. In our recent report, we show that during activation-induced cell death (AICD), the T-cell receptor (TCR)-dependent pathway that controls immune tolerance, autophagy is inhibited at an early stage. Further, we found that this inhibition is coupled with mitochondria fragmentation and cristae remodeling to unleash the apoptotic program. Last, we dissected the role of macroautophagy/autophagy versus mitophagy in the context of this physiological cell death, and bulk autophagy turned out to be able to remove dysfunctional and depolarized mitochondria. Our data suggest new possible approaches to modulate the immune function in the context of autoimmunity or immunotherapy.

  5. DAPk1 inhibits NF-κB activation through TNF-α and INF-γ-induced apoptosis.

    PubMed

    Yoo, Heon Jong; Byun, Hyun-Jung; Kim, Boh-Ram; Lee, Ki Hwan; Park, Sang-Yoon; Rho, Seung Bae

    2012-07-01

    Recent studies have shown DAPk as a molecular modulator induced by the second messenger, responsible for controlling cell destiny decisions, but the detailed mechanism mediating the role of DAPk1 during cell death is still not fully understood. In this present report, we attempted to characterize the effects of TNF-α and INF-γ on DAPk1 in human ovarian carcinoma cell lines, OVCAR-3. Both TNF-α and INF-γ significantly induce DAPk1 levels in a time-dependent manner. At the same time, they both arrested cell cycle progression in the G(0)-G(1) and G2/M phase, down-regulated cyclin D1, CDK4 and NF-κB expression, while also up-regulating p27 and p16 expression. Subsequently, the efficacy of the combined treatment with DAPk1 was investigated. In the presence of DAPk1, TNF-α or INF-γ-induced apoptosis was additively increased, while TNF-α or INF-γ-induced NF-κB activity was inhibited. Conversely, TNF-α or INF-γ-dependent NF-κB activity was further enhanced by the inhibition of DAPk1 with its specific siRNA. The activity of NF-κB was dependent on the level of DAPk1, indicating the requirement of DAPk1 for the activation of NF-κB. Low levels of DAPk1 expression were frequently observed in different human patient's tissue and cancer cell lines compared to normal samples. In addition, over-expression of DAPk1 from either TNF-α or INF-γ-treatment cells suppressed the anti-apoptosis protein XIAP as well as COX-2 and ICAM-1, more than control. Taken together, our data findings suggest that DAPk1 can mediate the pro-apoptotic activity of TNF-α and INF-γ via the NF-κB signaling pathways.

  6. Ghrelin inhibition of ethanol-induced gastric epithelial cell apoptosis is mediated by miR-21

    PubMed Central

    Jiang, Miao; Gao, Peng-Fei; Li, Huan-Qing; Tian, Pei-Ying; Fan, Xiao-Ming

    2015-01-01

    Aim: To investigate the underlying mechanism of ghrelin-induced gastro-protection in a cell culture model of ethanol-induced gastric epithelial cell injury. Methods: The human gastric epithelial cell line GES-1 was incubated with ghrelin (0.01-1 µM), 1 µM ghrelin and 1 µM D-Lys3-growth hormone releasing peptide-6 (GHRP-6), or 1 µM ghrelin and 400 nM antagomiR-21 for 24 h, followed by treatment with 8% ethanol for 3 h to induce apoptosis. Cell viability was determined by MTT assays and flow cytometry was used for detection of apoptosis rates. miR-21 transcription was analyzed by qRT-PCR and Akt, Bcl-2, Bax and caspase 3 expressions were measured by Western blot. Results: Flow cytometry and a quantitative RT-PCR analysis of the expression of miR-21 showed that ghrelin inhibited apoptosis in a dose dependent manner through a signaling pathway that was both growth hormone secretagogue receptor (GHS-R) and miR-21 dependent, as the antiapoptotic effect of ghrelin was blocked by both D-Lys3-GHRP-6 and antagomiR-21, respectively. Western blotting of Akt, Bcl-2, Bax, and caspase 3 showed that the levels of the antiapoptotic proteins, Akt and Bcl-2, in the cells pretreated with ghrelin alone were higher than those in the cells pretreated with D-Lys3-GHRP-6 or antagomiR-21. By contrast, the levels of the proapoptotic proteins, Bax and caspase 3, in the cells pretreated with ghrelin alone were lower than those in the cells pretreated with D-Lys3-GHRP-6 or antagomiR-21. Conclusion: Ghrelin inhibits GES-1 cell apoptosis through GHS-R-dependent signaling in which miR-21 activates the PI3K/Akt pathway, which upregulates Bcl-2 and downregulates Bax and caspase 3 expression. PMID:26191156

  7. Schisandrin B inhibits the proliferation of human lung adenocarcinoma A549 cells by inducing cycle arrest and apoptosis

    PubMed Central

    Lv, Xue-Jiao; Zhao, Li-Jing; Hao, Yu-Qiu; Su, Zhen-Zhong; Li, Jun-Yao; Du, Yan-Wei; Zhang, Jie

    2015-01-01

    Lung cancer is the leading cause of cancer death in the world. Schizandrin B (Sch B) is one of the main dibenzocyclooctadiene lignans present in the fruit of Schisandra chinensis (Schisandraceae). Sch B has multiple functions against cancer. The aim of this study was to determine the effect of Sch B on the proliferation, cell cycling, apoptosis and invasion of lung adenocarcinoma A549 cells by MTT, flow cytometry, wound healing and transwell invasion assays. Treatment with Sch B inhibited the proliferation of A549 cells in a dose-dependent manner. Sch B induced cell cycle arrest at G0/G1 phase by down-regulating the expression of cyclin D1, cyclin-dependent kinase (CDK)4, and CDK6, but up-regulating p53 and p21 expression in A549 cells. Furthermore, Sch B triggered A549 cell apoptosis by increasing Bax, cleaved caspase-3, 9, Cyto C, but decreasing Bcl-2 and PCNA expression. In addition, Sch B inhibited the invasion and migration of A549 cells by down-regulating the expressions of HIF-1, VEGF, MMP-9 and MMP-2. Therefore, Sch B has potent anti-tumor activity and may be a promising traditional Chinese medicine for human lung carcinoma. PMID:26221229

  8. Dragon (repulsive guidance molecule RGMb) inhibits E-cadherin expression and induces apoptosis in renal tubular epithelial cells.

    PubMed

    Liu, Wenjing; Li, Xiaoling; Zhao, Yueshui; Meng, Xiao-Ming; Wan, Chao; Yang, Baoxue; Lan, Hui-Yao; Lin, Herbert Y; Xia, Yin

    2013-11-01

    Dragon is one of the three members of the repulsive guidance molecule (RGM) family, i.e. RGMa, RGMb (Dragon), and RGMc (hemojuvelin). We previously identified the RGM members as bone morphogenetic protein (BMP) co-receptors that enhance BMP signaling. Our previous studies found that Dragon is highly expressed in the tubular epithelial cells of mouse kidneys. However, the roles of Dragon in renal epithelial cells are yet to be defined. We now show that overexpression of Dragon increased cell death induced by hypoxia in association with increased cleaved poly(ADP-ribose) polymerase and cleaved caspase-3 levels in mouse inner medullary collecting duct (IMCD3) cells. Dragon also inhibited E-cadherin expression but did not affect epithelial-to-mesenchymal transition induced by TGF-β in IMCD3 cells. Previous studies suggest that the three RGM members can function as ligands for the receptor neogenin. Interestingly, our present study demonstrates that the Dragon actions on apoptosis and E-cadherin expression in IMCD3 cells were mediated by the neogenin receptor but not through the BMP pathway. Dragon expression in the kidney was up-regulated by unilateral ureteral obstruction in mice. Compared with wild-type mice, heterozygous Dragon knock-out mice exhibited 45-66% reduction in Dragon mRNA expression, decreased epithelial apoptosis, and increased tubular E-cadherin expression and had attenuated tubular injury after unilateral ureteral obstruction. Our results suggest that Dragon may impair tubular epithelial integrity and induce epithelial apoptosis both in vitro and in vivo.

  9. Inhibition of autophagy by 3-MA potentiates purvalanol-induced apoptosis in Bax deficient HCT 116 colon cancer cells.

    PubMed

    Coker-Gurkan, Ajda; Arisan, Elif Damla; Obakan, Pinar; Guvenir, Esin; Unsal, Narcin Palavan

    2014-10-15

    The purine-derived analogs, roscovitine and purvalanol are selective synthetic inhibitors of cyclin-dependent kinases (CDKs) induced cell cycle arrest and lead to apoptotic cell death in various cancer cells. Although a number of studies investigated the molecular mechanism of each CDK inhibitor on apoptotic cell death mechanism with their therapeutic potential, their regulatory role on autophagy is not clarified yet. In this paper, our aim was to investigate molecular mechanism of CDK inhibitors on autophagy and apoptosis in wild type (wt) and Bax deficient HCT 116 cells. Exposure of HCT 116 wt and Bax(-/-) cells to roscovitine or purvalanol for 24h decreased cell viability in dose-dependent manner. However, Bax deficient HCT 116 cells were found more resistant against purvalanol treatment compared to wt cells. We also established that both CDK inhibitors induced apoptosis through activating mitochondria-mediated pathway in caspase-dependent manner regardless of Bax expression in HCT 116 colon cancer cells. Concomitantly, we determined that purvalanol was also effective on autophagy in HCT 116 colon cancer cells. Inhibition of autophagy by 3-MA treatment enhanced the purvalanol induced apoptotic cell death in HCT 116 Bax(-/-) cells. Our results revealed that mechanistic action of each CDK inhibitor on cell death mechanism differs. While purvalanol treatment activated apoptosis and autophagy in HCT 116 cells, roscovitine was only effective on caspase-dependent apoptotic pathway. Another important difference between two CDK inhibitors, although roscovitine treatment overcame Bax-mediated drug resistance in HCT 116 cells, purvalanol did not exert same effect.

  10. Short-term zinc deficiency inhibits chondrocyte proliferation and induces cell apoptosis in the epiphyseal growth plate of young chickens.

    PubMed

    Wang, Xibin; Fosmire, Gary J; Gay, Carol V; Leach, Roland M

    2002-04-01

    The purpose of this study was to investigate the effect of zinc deficiency on chondrocyte proliferation, differentiation and apoptosis in the epiphyseal growth plate of juvenile chickens. Newly hatched broiler chickens were fed either a low zinc (10 mg/kg diet) or a zinc-adequate (68 mg/kg diet) soy protein-based purified diet. Cell proliferation in the growth plate was evaluated with bromodeoxyuridine (BrdU) labeling. Apoptosis was assessed using the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) method. Chondrocyte differentiation was evaluated with immunostaining of osteonectin as a marker of maturation. As early as d 3 of feeding, zinc deficiency significantly inhibited chondrocyte proliferation, promoted cell differentiation and induced cell apoptosis in the growth plate. These effects were manifested primarily in areas remote from the blood supply. Immunostaining for local growth factors such as insulin-like growth factor-1 (IGF-1), parathyroid hormone-related protein (PTHrP) and fibroblast growth factor-2 (FGF-2) did not reveal any differences between growth plates of zinc-deficient and zinc-adequate chickens after 3 d of feeding. By d 7, severe growth plate lesions characterized by reduced cellularity and abnormally shaped cells were formed in areas remote from blood vessels. Immunoreactive IGF-1, PTHrP and FGF-2 were all greatly reduced in the lesion. However, the growth rate and food intake of zinc-deficient chickens were not different from those of the controls during the 7-d experiment. Therefore, a direct effect of zinc deficiency on proliferation, differentiation, and apoptosis of growth plate chondrocytes was indicated.

  11. Gambogic acid potentiates the chemosensitivity of colorectal cancer cells to 5-fluorouracil by inhibiting proliferation and inducing apoptosis

    PubMed Central

    Wei, Jianchang; Yang, Ping; Li, Wanglin; He, Feng; Zeng, Shanqi; Zhang, Tong; Zhong, Junbin; Huang, Di; Chen, Zhuanpeng; Wang, Chengxing; Chen, Huacui; Hu, He; Cao, Jie

    2017-01-01

    Chemotherapy using 5-fluorouracil (5-FU) for colorectal cancer (CRC) has low specificity and response rates, leading to severe side effects. Gambogic acid (GA), a traditional Chinese medicine, has multi-targeted anticancer effects, including growth inhibition and apoptosis induction. However, it is unclear whether a combination of 5-FU and GA has synergistic anticancer effects in CRC cells. In this study, SW480 and HCT116 human CRC cells and human intestinal epithelial cells (IECs) were treated with different concentrations of 5-FU, GA or 5-FU+GA. A Cell Counting kit-8 assay was conducted to quantify cell proliferation. The combination index (CI) was calculated and the median-effect principle was applied to analyze the interaction between 5-FU and GA. Flow cytometry was used to determine the percentage of cells undergoing apoptosis. Reverse transcription-quantitative polymerase chain reaction and western blotting were applied to measure P53, survivin and thymidylate synthase (TS) mRNA and protein levels. It was found that 5-FU+GA more pronouncedly inhibited cell growth and induced apoptosis, compared with either monotherapy. CI values <1 indicated the synergistic effects of the drugs. 5-FU+GA further decreased P53, survivin and TS mRNA and protein levels in the two CRC cell lines compared with single drugs, whereas increased P53 protein levels were observed in HCT116 cells. Moreover, 5-FU+GA did not increase cytotoxicity to IECs. These results demonstrate that GA enhances the anticancer effects of 5-FU on CRC cells. Combined treatment with 5-FU and GA is effective and safe for CRC cells, and may become a promising chemotherapy treatment. PMID:28352348

  12. Inhibition of LDH-A by oxamate induces G2/M arrest, apoptosis and increases radiosensitivity in nasopharyngeal carcinoma cells.

    PubMed

    Zhai, Xiaoming; Yang, Yang; Wan, Jianmei; Zhu, Ran; Wu, Yiwei

    2013-12-01

    An elevated rate of glucose consumption and the dependency on aerobic glycolysis for ATP generation have long been observed in cancer cells, a phenomenon known as the Warburg effect. the altered energy metabolism in cancer cells provides an attractive opportunity for developing novel cancer therapeutic strategies. Lactate dehydrogenase (LDH), which catalyzes the transformation of pyruvate to lactate, plays a vital role in the process of glycolysis. It has been reported that the level of LDH-A expression is increased both in head and neck cancer cells and in the blood serum of nasopharyngeal carcinoma (NPC) patients, and is associated with poor prognosis. However, the effect of LDH-A inhibition on NPC cells remains unknown. Here, in the present study, we found that oxamate, a classical inhibitor of LDH-A, suppressed cell proliferation in a dose- and time-dependent manner both in CNE-1 and CNE-2 cells, two NPC cancer cell lines. LDH inhibition by oxamate induced G2/M cell cycle arrest via downregulation of the CDK1/cyclin B1 pathway and promoted apoptosis through enhancement of mitochondrial ROS generation. N-acetylcysteine, a specific scavenger of ROS, significantly blocked the growth inhibition effect induced by oxamate. We also identified that oxamate increased sensitivity to ionizing radiation in the two NPC cancer cell lines. Furthermore, we verified similar results in tumor xenograft models. collectively, these results suggest that LDH-A may serve as a promising therapeutic target for NPC treatment.

  13. Sedum sarmentosum Bunge extract induces apoptosis and inhibits proliferation in pancreatic cancer cells via the hedgehog signaling pathway.

    PubMed

    Bai, Yongheng; Chen, Bicheng; Hong, Weilong; Liang, Yong; Zhou, Mengtao; Zhou, Lan

    2016-05-01

    Sedum sarmentosum Bunge, a traditional Chinese herbal medicine, has a wide range of clinical applications including antibiosis, anti-inflammation and anti-oxidation. In the present study, we identified that its extract (SSBE) exerts pancreatic anticancer activity in vitro and in vivo. In the cultured pancreatic cancer PANC-1 cell line, SSBE inhibited cell growth in a concentration-dependent manner, and it was accompanied by the downregulated expression of proliferating cell nuclear antigen (PCNA). In addition, SSBE treatment also increased cellular apoptosis in a mitochondrial-dependent manner. Moreover, SSBE induced p53 expression, reduced c-Myc expression, and inhibited epithelial-mesenchymal transition (EMT). The antiproliferative activity of SSBE in the pancreatic cancer cells was found to be closely related to cell cycle arrest at the G2/M phase by upregulating p21(Waf1/CIP1) expression. Further study showed that this inhibitory effect of SSBE was through downregulation of the activity of the proliferation-related Hedgehog signaling pathway. Exogenous recombinant protein Shh was used to activate Hedgehog signaling, thereby resulting in the abolishment of the SSBE-mediated inhibition of pancreatic cancer cell growth. In animal xenograft models of pancreatic cancer, activated Hedgehog signaling was also observed compared with the vehicle controls, but was reduced by SSBE administration. As a result, SSBE suppressed the growth of pancreatic tumors. Thus, these findings demonstrate that SSBE has therapeutic potential for pancreatic cancer, and this anticancer effect in pancreatic cancer cells is associated with inhibition of the Hedgehog signaling pathway.

  14. A novel platinum compound inhibits constitutive Stat3 signaling and induces cell cycle arrest and apoptosis of malignant cells.

    PubMed

    Turkson, James; Zhang, Shumin; Mora, Linda B; Burns, Audrey; Sebti, Said; Jove, Richard

    2005-09-23

    Previous studies have established constitutive activation of Stat3 protein as one of the molecular changes required for tumorigenesis. To develop novel therapeutics for tumors harboring constitutively active Stat3, compounds from the NCI 2000 diversity set were evaluated for inhibition of Stat3 DNA-binding activity in vitro. Of these, a novel platinum (IV) compound, IS3 295, interacted with Stat3 and inhibited its binding to specific DNA-response elements. Further analysis suggested noncompetitive-type kinetics for the inhibition of Stat3 binding to DNA. In human and mouse tumor cell lines with constitutively active Stat3, IS3 295 selectively attenuated Stat3 signaling, thereby inducing cell growth arrest at G0/G1 phase and apoptosis. Moreover, in transformed cells, IS3 295 repressed expression of cyclin D1 and bcl-xL, two of the known Stat3-regulated genes that are overexpressed in malignant cells, suggesting that IS3 295 mediates anti-tumor cell activity in part by blocking Stat3-mediated sub-version of cell growth and apoptotic signals. Together, our findings provide evidence for the inhibition of Stat3 activity and biological functions by IS3 295 through interaction with Stat3 protein. This study represents a significant advance in small molecule-based approaches to target Stat3 and suggests potential new applications for platinum (IV) complexes as modulators of the Stat3 pathway for cancer therapy.

  15. Tetrahydroxystilbene glucoside attenuates MPP+-induced apoptosis in PC12 cells by inhibiting ROS generation and modulating JNK activation.

    PubMed

    Li, Xiaobing; Li, Yan; Chen, Jianzong; Sun, Jing; Li, Xiaofeng; Sun, Xin; Kang, Xiaogang

    2010-10-08

    It is known that oxidative stress plays a major role in the progression of Parkinson's disease (PD). Previous studies have suggested that 2,3,5,4'-tetrahydroxystilbene-2-O-beta-D-glucoside (TSG), an active component extracted from a traditional Chinese herb Polygonum multiflorum Thunb., has significant antioxidant and free radical-scavenging activities. This is the first study that investigated the protective effects of TSG against MPP(+)-induced apoptosis in PC12 cells and determined the underlying mechanism. The results showed that incubation of PC12 cells with TSG before exposing them to MPP(+) could significantly decrease cell viability loss and reverse cell apoptosis in a dose-dependent manner. The anti-apoptotic effects of TSG were probably mediated via the inhibition of ROS generation and modulation of JNK activation because TSG blocked ROS increase and JNK phosphorylation induced by MPP(+). Taken together, these results indicated that TSG may provide a useful therapeutic strategy for the treatment of neurodegenerative diseases such as PD.

  16. Neuroprotective effects of sevoflurane against electromagnetic pulse-induced brain injury through inhibition of neuronal oxidative stress and apoptosis.

    PubMed

    Deng, Bin; Xu, Hao; Zhang, Jin; Wang, Jin; Han, Li-Chun; Li, Li-Ya; Wu, Guang-Li; Hou, Yan-Ning; Guo, Guo-Zhen; Wang, Qiang; Sang, Han-Fei; Xu, Li-Xian

    2014-01-01

    Electromagnetic pulse (EMP) causes central nervous system damage and neurobehavioral disorders, and sevoflurane protects the brain from ischemic injury. We investigated the effects of sevoflurane on EMP-induced brain injury. Rats were exposed to EMP and immediately treated with sevoflurane. The protective effects of sevoflurane were assessed by Nissl staining, Fluoro-Jade C staining and electron microscopy. The neurobehavioral effects were assessed using the open-field test and the Morris water maze. Finally, primary cerebral cortical neurons were exposed to EMP and incubated with different concentration of sevoflurane. The cellular viability, lactate dehydrogenase (LDH) release, superoxide dismutase (SOD) activity and malondialdehyde (MDA) level were assayed. TUNEL staining was performed, and the expression of apoptotic markers was determined. The cerebral cortexes of EMP-exposed rats presented neuronal abnormalities. Sevoflurane alleviated these effects, as well as the learning and memory deficits caused by EMP exposure. In vitro, cell viability was reduced and LDH release was increased after EMP exposure; treatment with sevoflurane ameliorated these effects. Additionally, sevoflurane increased SOD activity, decreased MDA levels and alleviated neuronal apoptosis by regulating the expression of cleaved caspase-3, Bax and Bcl-2. These findings demonstrate that Sevoflurane conferred neuroprotective effects against EMP radiation-induced brain damage by inhibiting neuronal oxidative stress and apoptosis.

  17. S100A8/A9 induces apoptosis and inhibits metastasis of CasKi human cervical cancer cells.

    PubMed

    Qin, Fengjin; Song, Yao; Li, Zijian; Zhao, Ling; Zhang, Youyi; Geng, Li

    2010-09-01

    S100 proteins, a family of Ca(2+)-binding proteins, have been linked to several human diseases in recent years. Deregulated expression of S100 proteins, including S100A9 and its partner S100A8, was reported to be associated with neoplastic disorders. In our previous study using serial analysis of gene expression, we identified decreased expressions of S100A9 and S100A8 in human cervical squamous cell carcinoma. To investigate the functions of S100A8 and S100A9 in cervical cancer, we purified recombinant S100A8 and S100A9 proteins and treated CaSki human cervical cancer cells with these proteins. We found that S100A8/A9 induced apoptosis and inhibited migration of CaSki cells; S100A8/A9 also reduced the expression of matrix metalloproteinase (MMP)-2 in CaSki cells. In summary, this study suggests that S100A8 and S100A9 have inhibitory effects on the proliferation of CaSki carcinoma cells by inducing cell apoptosis and on the invasiveness of CaSki cells.

  18. Osthole Attenuates Doxorubicin-Induced Apoptosis in PC12 Cells through Inhibition of Mitochondrial Dysfunction and ROS Production

    PubMed Central

    Shokoohinia, Yalda; Hosseinzadeh, Leila; Moieni-Arya, Maryam; Mostafaie, Ali; Mohammadi-Motlagh, Hamid-Reza

    2014-01-01

    Doxorubicin (DOX) is a potent, broad-spectrum chemotherapeutic drug used for treatment of several types of cancers. Despite its effectiveness, it has a wide range of toxic side effects, many of which most likely result from its inherent prooxidant activity. It has been reported that DOX has toxic effects on normal tissues, including brain tissue. In the current study, we investigated the protective effect of osthole isolated from Prangos ferulacea (L.) Lindl. on oxidative stress and apoptosis induced by DOX in PC12 as a neuronal model cell line. PC12 cells were pretreated with osthole 2 h after treatment with different concentrations of DOX. 24 h later, the cell viability, mitochondrial membrane potential (MMP), the activity of caspase-3, the expression ratio of Bax/Bcl-2, and the generation of intracellular ROS were detected. We found that pretreatment with osthole on PC12 cells significantly reduced the loss of cell viability, the activity of caspase-3, the increase in Bax/Bcl-2 ratio, and the generation of intracellular ROS induced by DOX. Moreover, pretreatment with osthole led to an increase in MMP in PC12 cells. In conclusion, our results indicated that pretreatment with nontoxic concentrations of osthole protected PC12 cells from DOX-mediated apoptosis by inhibition of ROS production. PMID:25013759

  19. 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

  20. Inhibition of PPARα induces cell cycle arrest and apoptosis, and synergizes with glycolysis inhibition in kidney cancer cells.

    PubMed

    Abu Aboud, Omran; Wettersten, Hiromi I; Weiss, Robert H

    2013-01-01

    Renal cell carcinoma (RCC) is the sixth most common cancer in the US. While RCC is highly metastatic, there are few therapeutics options available for patients with metastatic RCC, and progression-free survival of patients even with the newest targeted therapeutics is only up to two years. Thus, novel therapeutic targets for this disease are desperately needed. Based on our previous metabolomics studies showing alteration of peroxisome proliferator-activated receptor α (PPARα) related events in both RCC patient and xenograft mice materials, this pathway was further examined in the current study in the setting of RCC. PPARα is a nuclear receptor protein that functions as a transcription factor for genes including those encoding enzymes involved in energy metabolism; while PPARα has been reported to regulate tumor growth in several cancers, it has not been evaluated in RCC. A specific PPARα antagonist, GW6471, induced both apoptosis and cell cycle arrest at G0/G1 in VHL(+) and VHL(-) RCC cell lines (786-O and Caki-1) associated with attenuation of the cell cycle regulatory proteins c-Myc, Cyclin D1, and CDK4; this data was confirmed as specific to PPARα antagonism by siRNA methods. Interestingly, when glycolysis was blocked by several methods, the cytotoxicity of GW6471 was synergistically increased, suggesting a switch to fatty acid oxidation from glycolysis and providing an entirely novel therapeutic approach for RCC.

  1. Inhibition of proteasomal degradation of Mcl-1 by cobalt chloride suppresses cobalt chloride-induced apoptosis in HCT116 colorectal cancer cells.

    PubMed

    Lee, Melanie; Lapham, Abigail; Brimmell, Matthew; Wilkinson, Helen; Packham, Graham

    2008-08-01

    Cobalt promotes apoptosis in multiple cell systems, however, the molecular mechanisms that influence cobalt-induced apoptosis are not fully understood. We investigated mechanisms of cobalt chloride induced apoptosis in HCT116 colorectal cancer cells. Cobalt chloride induced dose dependent apoptosis in HCT116 cells (250-750 muM) which, at higher concentrations (500-750 muM), was associated with an increase in the expression of the Bcl-2-related Mcl-1 survival protein. Cobalt chloride caused the accumulation of higher molecular weight ubiquitin-conjugates of Mcl-1 in intact HCT116 cells and inhibited the activity of the trypsin-like site of the 20S proteasome in an in vitro assay. Although siRNA-mediated knockdown of Mcl-1 increased apoptosis in HCT116 cells, the combination of Mcl-1 siRNA and cobalt chloride induced very high levels of cell killing. Therefore, inhibition of the proteasome by cobalt chloride leads to the accumulation of Mcl-1 which acts to limit cobalt chloride induced apoptosis.

  2. Autophagy inhibition enhances isorhamnetin-induced mitochondria-dependent apoptosis in non-small cell lung cancer cells

    PubMed Central

    RUAN, YUSHU; HU, KE; CHEN, HONGBO

    2015-01-01

    Isorhamnetin (ISO) is a flavonoid from plants of the Polygonaceae family and is also an immediate metabolite of quercetin in mammals. To date, the anti-tumor effects of ISO and the underlying mechanisms have not been elucidated in lung cancer cells. The present study investigated the inhibitory effects of ISO on the growth of human lung cancer A549 cells. Treatment of the lung cancer cells with ISO significantly suppressed cell proliferation and colony formation. ISO treatment also resulted in a significant increase in apoptotic cell death of A549 cells in a time- and dose-dependent manner. Further investigation showed that the apoptosis proceeded via the mitochondria-dependent pathway as indicated by alteration of the mitochondrial membrane potential, the release of cytochrome C and caspase activation. Of note, treatment with ISO also induced the formation of autophagosomes and light chain 3-II protein in A549 cells. Furthermore, co-treatment with autophagy inhibitors 3-methyladenine and hydroxychloroquine significantly inhibited the ISO-induced autophagy and enhanced the ISO-induced apoptotic cell death in vitro as well as in vivo. Thus, the results of the present study suggested that ISO is a potential anti-lung cancer agent. In addition, the results indicated that the inhibition of autophagy may be a useful strategy for enhancing the chemotherapeutic effect of ISO on lung cancer cells. PMID:26238746

  3. Dephosphorylation of threonine-821 of the retinoblastoma tumor suppressor protein (Rb) is required for apoptosis induced by UV and Cdk inhibition.

    PubMed

    Lentine, Brandon; Antonucci, Lisa; Hunce, Ray; Edwards, Justina; Marallano, Valerie; Krucher, Nancy A

    2012-09-01

    The Retinoblastoma protein (Rb) is important in the control of cell proliferation and apoptosis. Its activity is controlled by reversible phosphorylation on several serine and threonine residues. When Rb is hypophosphorylated, it inhibits proliferation by preventing passage through the G 1- S phase transition. Hyperphosphorylated Rb promotes cell cycle progression. The role of Rb phosphorylation in the control of apoptosis is largely unknown, although several apoptotic stimuli result in dephosphorylation of Rb. It may be that dephosphorylation of specific amino acids signals apoptosis vs. cell cycle arrest. Using glutamic acid mutagenesis, we have generated 15 single phosphorylation site mutants of Rb to alter serine/threonine to glutamic acid to mimic the phosphorylated state. By calcium phosphate transfection, mutant plasmids were introduced into C33A Rb-null cells, and apoptosis was induced using UV. Apoptosis was measured by ELISA detection of degraded DNA and by immunoblotting to assess proteolytic cleavage of PARP. Our results show that only mutation of threonine-821 to glutamic acid (T821E) blocked apoptosis by 50%, whereas other sites tested had little effect. In Rb-null Saos-2 and SKUT-1 cells, the T821E mutation also blocked apoptosis induced by the cdk inhibitor, Roscovitine, by 50%. In addition, we show that endogenous Rb is dephosphorylated on threonine-821 when cells are undergoing apoptosis. Thus, our data indicates that dephosphorylation of threonine-821 of Rb is required for cells to undergo apoptosis.

  4. Retracted: Knockdown of tumor protein D52-like 2 induces cell growth inhibition and apoptosis in oral squamous cell carcinoma.

    PubMed

    2016-03-01

    The above article, published online on 13 October 2014 in Wiley Online Library (http://onlinelibrary.wiley.com/doi/10.1002/cbin.10388/abstract), has been retracted by agreement between the authors, the journal Editor, Sergio Schenkman, and John Wiley & Sons Ltd. The retraction has been agreed because the authors discovered after publication that one of the cell lines described in the article had been unintentionally misidentified. The experiments described in the article as being conducted on Human Oral Squamous Cell Carcinoma cell line KB were in fact conducted on a Human Oral Epidermal-like Cancer cell line. The authors and publisher apologise for any inconvenience. References He Y, Chen F, Cai Y and Chen S (2015) Knockdown of tumor protein D52-like 2 induces cell growth inhibition and apoptosis in oral squamous cell carcinoma. Cell Biology International 39: 264-271. doi: 10.1002/cbin.10388.

  5. Glutamate-induced apoptosis in neuronal cells is mediated via caspase-dependent and independent mechanisms involving calpain and caspase-3 proteases as well as apoptosis inducing factor (AIF) and this process is inhibited by equine estrogens

    PubMed Central

    Zhang, YueMei; Bhavnani, Bhagu R

    2006-01-01

    Background Glutamate, a major excitatory amino acid neurotransmitter, causes apoptotic neuronal cell death at high concentrations. Our previous studies have shown that depending on the neuronal cell type, glutamate-induced apoptotic cell death was associated with regulation of genes such as Bcl-2, Bax, and/or caspase-3 and mitochondrial cytochrome c. To further delineate the intracellular mechanisms, we have investigated the role of calpain, an important calcium-dependent protease thought to be involved in apoptosis along with mitochondrial apoptosis inducing factor (AIF) and caspase-3 in primary cortical cells and a mouse hippocampal cell line HT22. Results Glutamate-induced apoptotic cell death in neuronal cells was associated with characteristic DNA fragmentation, morphological changes, activation of calpain and caspase-3 as well as the upregulation and/or translocation of AIF from mitochondria into cytosol and nuclei. Our results reveal that primary cortical cells and HT22 cells display different patterns of regulation of these genes/proteins. In primary cortical cells, glutamate induces activation of calpain, caspase-3 and translocation of AIF from mitochondria to cytosol and nuclei. In contrast, in HT22 cells, only the activation of calpain and upregulation and translocation of AIF occurred. In both cell types, these processes were inhibited/reversed by 17β-estradiol and Δ8,17β-estradiol with the latter being more potent. Conclusion Depending upon the neuronal cell type, at least two mechanisms are involved in glutamate-induced apoptosis: a caspase-3-dependent pathway and a caspase-independent pathway involving calpain and AIF. Since HT22 cells lack caspase-3, glutamate-induced apoptosis is mediated via the caspase-independent pathway in this cell line. Kinetics of this apoptotic pathway further indicate that calpain rather than caspase-3, plays a critical role in the glutamate-induced apoptosis. Our studies further indicate that glutamate- induced changes

  6. Wedelolactone, a medicinal plant-derived coumestan, induces caspase-dependent apoptosis in prostate cancer cells via downregulation of PKCε without inhibiting Akt

    PubMed Central

    SARVESWARAN, SIVALOKANATHAN; GAUTAM, SUBHASH C.; GHOSH, JAGADANANDA

    2012-01-01

    Emerging studies indicate that metabolism of arachidonic acid through the 5-lipoxygenase (5-Lox) pathway plays a critical role in the survival of prostate cancer cells raising the possibility that 5-Lox can be targeted for an effective therapy of prostate cancer. Wedelolactone (WDL), a medicinal plant-derived natural compound, is known to inhibit 5-Lox activity in neutrophils. However, its effect on apoptosis in prostate cancer cells has not been addressed. Thus, we tested the effects of WDL on human prostate cancer cells in vitro. We observed that WDL kills both androgen-sensitive as well as androgen-independent prostate cancer cells in a dose-dependent manner by dramatically inducing apoptosis. We also found that WDL-induced apoptosis in prostate cancer cells is dependent on c-Jun N-terminal Kinase (c-JNK) and caspase-3. Interestingly, WDL triggers apoptosis in prostate cancer cells via downregulation of protein kinase Cε (PKCε), but without inhibition of Akt. WDL does not affect the viability of normal prostate epithelial cells (PrEC) at doses that kill prostate cancer cells, and WDL-induced apoptosis is effectively prevented by 5-oxoETE, a metabolite of 5-Lox (but not by 15-oxoETE, a metabolite of 15-Lox), suggesting that the apoptosis-inducing effect of WDL in prostate cancer cells is mediated via inhibition of 5-Lox activity. These findings indicate that WDL selectivity induces caspase-dependent apoptosis in prostate cancer cells via a novel mechanism involving inhibition of PKCε without affecting Akt and suggest that WDL may emerge as a novel therapeutic agent against clinical prostate cancer in human. PMID:23076676

  7. A Novel Natural Product, KL-21, Inhibits Proliferation and Induces Apoptosis in Chronic Lymphocytic Leukemia Cells

    PubMed Central

    Adan Gökbulut, Aysun; Yaşar, Mustafa; Baran, Yusuf

    2015-01-01

    Objective: The aims of this study were to examine the cytotoxic and apoptotic effects of KL-21, a novel plant product (produced by Naturin Natural Products, İzmir, Turkey), on 232B4 chronic lymphocytic leukemia (CLL) cells and to determine the cytotoxic effects on healthy BEAS-2B human bronchial epithelial cells. Materials and Methods: The cytotoxic effect of KL-21 was determined by MTT cell proliferation assay. Changes in caspase-3 enzyme activity were measured using the caspase-3 colorimetric assay. Changes in mitochondrial membrane potential were determined using the JC-1 dye-based method. Annexin V-FITC/PI double staining was performed to measure the apoptotic cell population. Effects of KL-21 on cell cycle profiles of CLL cells were investigated by flow cytometry. Results: We detected time- and concentration-dependent increases in the cytotoxic effect of KL-21 on 232B4 CLL cells. However, we also showed that, especially at higher concentrations, KL-21 was less cytotoxic towards BEAS-2B healthy cells than towards CLL cells. Annexin-V/PI double staining results showed that the apoptotic cell population increased in 232B4 cells. Increasing concentrations of KL-21 increased caspase-3 enzyme activity and induced loss of mitochondrial membrane potential. KL-21 administration resulted in small increases in the percentage of the cells in the G0/G1 phase while it decreased the S phase cell population up to 1 mg/mL. At the highest concentration, most of the cells accumulated in the G0/G1 phase. Conclusion: KL-21 has a growth-inhibitory effect on 232B4 CLL cells. KL-21 causes apoptosis and cell cycle arrest at G0/G1. PMID:26316479

  8. Romidepsin reduces histone deacetylase activity, induces acetylation of histones, inhibits proliferation, and activates apoptosis in immortalized epithelial endometriotic cells.

    PubMed

    Imesch, Patrick; Fink, Daniel; Fedier, André

    2010-12-01

    Romidepsin inhibited HDAC activity, produced acetylation of the histone proteins, up-regulated p21, and down-regulated cyclins B1 and D1, resulting in proliferation inhibition and apoptosis activation in 11z immortalized epithelial endometriotic cells. Our findings provide evidence that endometriotic cells are sensitive to the epigenetic effects of romidepsin and suggest that endometriosis may be therapeutically targeted by romidepsin.

  9. Salinomycin inhibits Wnt signaling and selectively induces apoptosis in chronic lymphocytic leukemia cells.

    PubMed

    Lu, Desheng; Choi, Michael Y; Yu, Jian; Castro, Januario E; Kipps, Thomas J; Carson, Dennis A

    2011-08-09

    Salinomycin, an antibiotic potassium ionophore, has been reported recently to act as a selective breast cancer stem cell inhibitor, but the biochemical basis for its anticancer effects is not clear. The Wnt/β-catenin signal transduction pathway plays a central role in stem cell development, and its aberrant activation can cause cancer. In this study, we identified salinomycin as a potent inhibitor of the Wnt signaling cascade. In Wnt-transfected HEK293 cells, salinomycin blocked the phosphorylation of the Wnt coreceptor lipoprotein receptor related protein 6 (LRP6) and induced its degradation. Nigericin, another potassium ionophore with activity against cancer stem cells, exerted similar effects. In otherwise unmanipulated chronic lymphocytic leukemia cells with constitutive Wnt activation nanomolar concentrations of salinomycin down-regulated the expression of Wnt target genes such as LEF1, cyclin D1, and fibronectin, depressed LRP6 levels, and limited cell survival. Normal human peripheral blood lymphocytes resisted salinomycin toxicity. These results indicate that ionic changes induced by salinomycin and related drugs inhibit proximal Wnt signaling by interfering with LPR6 phosphorylation, and thus impair the survival of cells that depend on Wnt signaling at the plasma membrane.

  10. Growth inhibition and apoptosis in cancer cells induced by polyphenolic compounds of Acacia hydaspica: Involvement of multiple signal transduction pathways.

    PubMed

    Afsar, Tayyaba; Trembley, Janeen H; Salomon, Christine E; Razak, Suhail; Khan, Muhammad Rashid; Ahmed, Khalil

    2016-03-15

    Acacia hydaspica R. Parker is known for its medicinal uses in multiple ailments. In this study, we performed bioassay-guided fractionation of cytotoxic compounds from A. hydaspica and investigated their effects on growth and signaling activity in prostate and breast cancer cell lines. Four active polyphenolic compounds were identified as 7-O-galloyl catechin (GC), catechin (C), methyl gallate (MG), and catechin-3-O-gallate (CG). The four compounds inhibited prostate cancer PC-3 cell growth in a dose-dependent manner, whereas CG and MG inhibited breast cancer MDA-MB-231 cell growth. All tested compounds inhibited cell survival and colony growth in both cell lines, and there was evidence of chromatin condensation, cell shrinkage and apoptotic bodies. Further, acridine orange, ethidium bromide, propidium iodide and DAPI staining demonstrated that cell death occurred partly via apoptosis in both PC-3 and MDA-MB-231 cells. In PC-3 cells treatment repressed the expression of anti-apoptotic molecules Bcl-2, Bcl-xL and survivin, coupled with down-regulation of signaling pathways AKT, NFκB, ERK1/2 and JAK/STAT. In MDA-MB-231 cells, treatment induced reduction of CK2α, Bcl-xL, survivin and xIAP protein expression along with suppression of NFκB, JAK/STAT and PI3K pathways. Our findings suggest that certain polyphenolic compounds derived from A. hydaspica may be promising chemopreventive/therapeutic candidates against cancer.

  11. Growth inhibition and apoptosis in cancer cells induced by polyphenolic compounds of Acacia hydaspica: Involvement of multiple signal transduction pathways

    PubMed Central

    Afsar, Tayyaba; Trembley, Janeen H.; Salomon, Christine E.; Razak, Suhail; Khan, Muhammad Rashid; Ahmed, Khalil

    2016-01-01

    Acacia hydaspica R. Parker is known for its medicinal uses in multiple ailments. In this study, we performed bioassay-guided fractionation of cytotoxic compounds from A. hydaspica and investigated their effects on growth and signaling activity in prostate and breast cancer cell lines. Four active polyphenolic compounds were identified as 7-O-galloyl catechin (GC), catechin (C), methyl gallate (MG), and catechin-3-O-gallate (CG). The four compounds inhibited prostate cancer PC-3 cell growth in a dose-dependent manner, whereas CG and MG inhibited breast cancer MDA-MB-231 cell growth. All tested compounds inhibited cell survival and colony growth in both cell lines, and there was evidence of chromatin condensation, cell shrinkage and apoptotic bodies. Further, acridine orange, ethidium bromide, propidium iodide and DAPI staining demonstrated that cell death occurred partly via apoptosis in both PC-3 and MDA-MB-231 cells. In PC-3 cells treatment repressed the expression of anti-apoptotic molecules Bcl-2, Bcl-xL and survivin, coupled with down-regulation of signaling pathways AKT, NFκB, ERK1/2 and JAK/STAT. In MDA-MB-231 cells, treatment induced reduction of CK2α, Bcl-xL, survivin and xIAP protein expression along with suppression of NFκB, JAK/STAT and PI3K pathways. Our findings suggest that certain polyphenolic compounds derived from A. hydaspica may be promising chemopreventive/therapeutic candidates against cancer. PMID:26975752

  12. Ligustrazine-Oleanolic Acid Glycine Derivative, G-TOA, Selectively Inhibited the Proliferation and Induced Apoptosis of Activated HSC-T6 Cells.

    PubMed

    Bi, Siling; Chu, Fuhao; Wang, Mina; Li, Bi; Mao, Pei; Zhang, Huazheng; Wang, Penglong; Guo, Wenbo; Xu, Liang; Ren, Liwei; Lei, Haimin; Zhang, Yuzhong

    2016-11-23

    Hepatic fibrosis is a naturally occurring wound-healing reaction, with an imbalance of extracellular matrix (ECM) during tissue repair response, which can further deteriorate to hepatocellular carcinoma without timely treatment. Inhibiting activated hepatic stellate cell (HSC) proliferation and inducing apoptosis are the main methods for the treatment of liver fibrosis. In our previous study, we found that the TOA-glycine derivative (G-TOA) had exhibited more significant inhibitory activity against HepG2 cells and better hydrophilicity than TOA, ligustrazine (TMP), and oleanolic acid (OA). However, inhibiting activated HSC proliferation and inducing apoptosis by G-TOA had not been reported. In this paper, the selective cytotoxicity of G-TOA was evaluated on HSC-T6 cells and L02 cells, and apoptosis mechanisms were explored. It was found that G-TOA could selectively inhibit the proliferation of activated HSC-T6 cells, induce morphological changes, early apoptosis, and mitochondrial membrane potential depolarization, increase intracellular free calcium levels, downregulate the expression of NF-κB/p65 and COX-2 protein, and decrease the ratio of Bcl-2/Bax, thereby inducing HSC-T6 cell apoptosis. Thence, G-TOA might be a potential antifibrosis agent for the therapy of hepatic fibrosis, provided that it exerts anti-fibrosis effects on activated HSC-T6 cells.

  13. Overexpression of miR-34c inhibits high glucose-induced apoptosis in podocytes by targeting Notch signaling pathways.

    PubMed

    Liu, Xiang-Dong; Zhang, Lian-Yun; Zhu, Tie-Chui; Zhang, Rui-Fang; Wang, Shu-Long; Bao, Yan

    2015-01-01

    Recent findings have shown that microRNAs play critical roles in the pathogenesis of diabetic nephropathy. miR-34c has been found to inhibit fibrosis and the epithelial-mesenchymal transition of kidney cells. However, the role of miR-34c in diabetic nephropathy has not been well studied. The current study was designed to investigate the role and potential underlying mechanism of miR-34c in regulating diabetic nephropathy. After treating podocytes with high glucose (HG) in vitro, we found that miR-34c was downregulated and that overexpression of miR-34c inhibited HG-induced podocyte apoptosis. The direct interaction between miR-34c and the 3'-untranslated region (UTR) of Notch1 and Jagged1 was validated by dual-luciferase reporter assay. Moreover, Notch1 and Jagged1 as putative targets of miR-34c were downregulated by miR-34c overexpression in HG-treated podocytes. Overexpression of miR-34c inhibited HG-induced Notch signaling pathway activation, as indicated by decreased expression of the Notch intracellular domain (NICD) and downstream genes including Hes1 and Hey1. Furthermore, miR-34c overexpression increased the expression of the anti-apoptotic gene Bcl-2, and decreased the expression of the pro-apoptotic protein Bax and cleaved Caspase-3. Additionally, the phosphorylation of p53 was also downregulated by miR-34c overexpression. Taken together, our findings suggest that miR-34c overexpression inhibits the Notch signaling pathway by targeting Notch1 and Jaggged1 in HG-treated podocytes, representing a novel and potential therapeutic target for the treatment of diabetic nephropathy.

  14. Resveratrol Induces Cell Cycle Arrest and Apoptosis in Malignant NK Cells via JAK2/STAT3 Pathway Inhibition

    PubMed Central

    Quoc Trung, Ly; Espinoza, J. Luis; Takami, Akiyoshi; Nakao, Shinji

    2013-01-01

    Natural killer (NK) cell malignancies, particularly aggressive NK cell leukaemias and lymphomas, have poor prognoses. Although recent regimens with L-asparaginase substantially improved outcomes, novel therapeutic approaches are still needed to enhance clinical response. Resveratrol, a naturally occurring polyphenol, has been extensively studied for its anti-inflammatory, cardioprotective and anti-cancer activities. In this study, we investigated the potential anti-tumour activities of resveratrol against the NK cell lines KHYG-1, NKL, NK-92 and NK-YS. Resveratrol induced robust G0/G1 cell cycle arrest, significantly suppressed cell proliferation and induced apoptosis in a dose- and time-dependent manner for all four cell lines. In addition, resveratrol suppressed constitutively active STAT3 in all the cell lines and inhibited JAK2 phosphorylation but had no effect on other upstream mediators of STAT3 activation, such as PTEN, TYK2, and JAK1. Resveratrol also induced downregulation of the anti-apoptotic proteins MCL1 and survivin, two downstream effectors of the STAT3 pathway. Finally, resveratrol induced synergistic effect on the apoptotic and antiproliferative activities of L-asparaginase against KHYG-1, NKL and NK-92 cells. These results suggest that resveratrol may have therapeutic potential against NK cell malignancies. Furthermore, our finding that resveratrol is a bonafide JAK2 inhibitor extends its potential benefits to other diseases with dysregulated JAK2 signaling. PMID:23372833

  15. Propofol inhibits lung cancer cell viability and induces cell apoptosis by upregulating microRNA-486 expression

    PubMed Central

    Yang, N.; Liang, Y.; Yang, P.; Yang, T.; Jiang, L.

    2017-01-01

    Propofol is a frequently used intravenous anesthetic agent. Recent studies show that propofol exerts a number of non-anesthetic effects. The present study aimed to investigate the effects of propofol on lung cancer cell lines H1299 and H1792 and functional role of microRNA (miR)-486 in these effects. H1299 and/or H1792 cells were treated with or without propofol and transfected or not with miR-486 inhibitor, and then cell viability and apoptosis were analyzed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and flow cytometry. The expression of miR-486 was determined by quantitative real-time polymerase chain reaction (qRT-PCR) with or without propofol treatment. Western blot was performed to analyze the protein expression of Forkhead box, class O (FOXO) 1 and 3, Bcl-2 interacting mediator of cell death (Bim), and pro- and activated caspases-3. Results showed that propofol significantly increased the miR-486 levels in both H1299 and H1792 cells compared to untreated cells in a dose-dependent manner (P<0.05 or P<0.01). Propofol statistically decreased cell viability but increased the percentages of apoptotic cells and protein expressions of FOXO1, FOXO3, Bim, and pro- and activated caspases-3; however, miR-486 inhibitor reversed the effects of propofol on cell viability, apoptosis, and protein expression (P<0.05 or P<0.01). In conclusion, propofol might be an ideal anesthetic for lung cancer surgery by effectively inhibiting lung cancer cell viability and inducing cell apoptosis. Modulation of miR-486 might contribute to the anti-tumor activity of propofol. PMID:28076456

  16. Salvianolic Acid B Inhibits Hydrogen Peroxide-Induced Endothelial Cell Apoptosis through Regulating PI3K/Akt Signaling

    PubMed Central

    Liu, Chen-Li; Xie, Li-Xia; Li, Min; Durairajan, Siva Sundara Kumar; Goto, Shinya; Huang, Jian-Dong

    2007-01-01

    Background Salvianolic acid B (Sal B) is one of the most bioactive components of Salvia miltiorrhiza, a traditional Chinese herbal medicine that has been commonly used for prevention and treatment of cerebrovascular disorders. However, the mechanism responsible for such protective effects remains largely unknown. It has been considered that cerebral endothelium apoptosis caused by reactive oxygen species including hydrogen peroxide (H2O2) is implicated in the pathogenesis of cerebrovascular disorders. Methodology and Principal Findings By examining the effect of Sal B on H2O2-induced apoptosis in rat cerebral microvascular endothelial cells (rCMECs), we found that Sal B pretreatment significantly attenuated H2O2-induced apoptosis in rCMECs. We next examined the signaling cascade(s) involved in Sal B-mediated anti-apoptotic effects. We showed that H2O2 induces rCMECs apoptosis mainly through the PI3K/ERK pathway, since a PI3K inhibitor (LY294002) blocked ERK activation caused by H2O2 and a specific inhibitor of MEK (U0126) protected cells from apoptosis. On the other hand, blockage of the PI3K/Akt pathway abrogated the protective effect conferred by Sal B and potentated H2O2-induced apoptosis, suggesting that Sal B prevents H2O2-induced apoptosis predominantly through the PI3K/Akt (upstream of ERK) pathway. Significance Our findings provide the first evidence that H2O2 induces rCMECs apoptosis via the PI3K/MEK/ERK pathway and that Sal B protects rCMECs against H2O2-induced apoptosis through the PI3K/Akt/Raf/MEK/ERK pathway. PMID:18091994

  17. Overexpression of Hsp20 prevents endotoxin-induced myocardial dysfunction and apoptosis via inhibition of NF-kappaB activation.

    PubMed

    Wang, Xiaohong; Zingarelli, Basilia; O'Connor, Michael; Zhang, Pengyuan; Adeyemo, Adeola; Kranias, Evangelia G; Wang, Yigang; Fan, Guo-Chang

    2009-09-01

    The occurrence of cardiovascular dysfunction in sepsis is associated with a significantly increased mortality rate of 70% to 90% compared with 20% in septic patients without cardiovascular impairment. Thus, rectification or blockade of myocardial depressant factors should partly ameliorate sepsis progression. Heat shock protein 20 (Hsp20) has been shown to enhance myocardial contractile function and protect against doxorubicin-induced cardiotoxicity. To investigate the possible role of Hsp20 in sepsis-mediated cardiac injury, we first examined the expression profiles of five major Hsps in response to lipopolysaccharide (LPS) challenge, and observed that only the expression of Hsp20 was downregulated in LPS-treated myocardium, suggesting that this decrease might be one of the mechanisms contributing to LPS-induced cardiovascular defects. Further studies using loss-of-function and gain-of-function approaches in adult rat cardiomyocytes verified that reduced Hsp20 levels were indeed correlated with the impaired contractile function. In fact, overexpression of Hsp20 significantly enhanced cardiomyocyte contractility upon LPS treatment. Moreover, after administration of LPS (25 microg/g) in vivo, Hsp20 transgenic mice (10-fold overexpression) displayed: 1) an improvement in myocardial function; 2) reduced the degree of cardiac apoptosis; and 3) decreased NF-kappaB activity, accompanied with reduced myocardial cytokines IL-1beta and TNF-alpha production, compared to the LPS-treated non-transgenic littermate controls. Thus, the increases in Hsp20 levels can protect against LPS-induced cardiac apoptosis and dysfunction, associated with inhibition of NF-kappaB activity, suggesting that Hsp20 may be a new therapeutic agent for the treatment of sepsis.

  18. Scutellaria barbata D. Don inhibits growth and induces apoptosis by suppressing IL-6-inducible STAT3 pathway activation in human colorectal cancer cells

    PubMed Central

    JIANG, QIQIN; LI, QIONGYU; CHEN, HONGWEI; SHEN, ALING; CAI, QIAOYAN; LIN, JIUMAO; PENG, JUN

    2015-01-01

    One of the most critical cellular signal transduction pathways known to malfunction in colorectal cancer is the interleukin-6/signal transducer and activator of transcription 3 (IL-6/STAT3) pathway. Scutellaria barbata D. Don (SB) is well-known traditional medicine in China that targets STAT3 signaling, and it has long been used to treat various types of cancer; however, the precise mechanism of its antitumor activity remains largely unclear. In order to further elucidate this underlying mechanism, an ethanol extract of SB (EESB) in cancer treatment. The aim of the present study was to evaluate the effects of EESB on the IL-6-inducible STAT3 pathway. We tested the dose-response association between EESB, IL-6-induced proliferaion and apoptosis using an MTT assay, colony formation and flow cytometry analysis in vitro. In addition, caspase-9 and caspase-3 activation was determined using a colorimetric assay, the activity of IL-6-induced STAT3 pathway was evaluated using western blot analysis, and the expression levels of cyclin D1, cyclin-dependent kinase 4, Bcl2 and Bcl2-associated X were determined using reverse transcription-polymerase chain reaction and western blot analysis. In the present study it was found that EESB could significantly inhibit the IL-6-mediated increase in STAT3 phosphorylation levels and transcriptional activity in HT-29 human colon carcinoma cells, resulting in the suppression of cell proliferation and the induction of apoptosis. In addition, treatment with EESB markedly inhibited the IL-6-induced upregulation of cyclin D1 and B-cell lymphoma-2, two key target genes of the STAT3 pathway. These results suggest that treatment with EESB could effectively inhibit the proliferation and promote the apoptosis of human colon carcinoma cells via modulation of the IL-6/STAT3 signaling pathway and its target genes. PMID:26622533

  19. Heat shock protein 90-mediated inactivation of nuclear factor-κB switches autophagy to apoptosis through becn1 transcriptional inhibition in selenite-induced NB4 cells.

    PubMed

    Jiang, Qian; Wang, Yuhan; Li, Tianjiao; Shi, Kejian; Li, Zhushi; Ma, Yushi; Li, Feng; Luo, Hui; Yang, Yang; Xu, Caimin

    2011-04-15

    Autophagy can protect cells while also contributing to cell damage, but the precise interplay between apoptosis and autophagy and the contribution of autophagy to cell death are still not clear. Previous studies have shown that supranutritional doses of sodium selenite promote apoptosis in human leukemia NB4 cells. Here, we report that selenite treatment triggers opposite patterns of autophagy in the NB4, HL60, and Jurkat leukemia cell lines during apoptosis and provide evidence that the suppressive effect of selenite on autophagy in NB4 cells is due to the decreased expression of the chaperone protein Hsp90 (heat shock protein 90), suggesting a novel regulatory function of Hsp90 in apoptosis and autophagy. Excessive or insufficient expression indicates that Hsp90 protects NB4 cells from selenite-induced apoptosis, and selenite-induced decreases in the expression of Hsp90, especially in NB4 cells, inhibit the activities of the IκB kinase/nuclear factor-κB (IKK/NF-κB) signaling pathway, leading to less nuclear translocation and inactivation of NF-κB and the subsequent weak binding of the becn1 promoter, which facilitates the transition from autophagy to apoptosis. Taken together, our observations provide novel insights into the mechanisms underlying the balance between apoptosis and autophagy, and we also identified Hsp90-NF-κB-Beclin1 as a potential biological pathway for signaling the switch from autophagy to apoptosis in selenite-treated NB4 cells.

  20. Alantolactone induces apoptosis of human cervical cancer cells via reactive oxygen species generation, glutathione depletion and inhibition of the Bcl-2/Bax signaling pathway

    PubMed Central

    JIANG, YAN; XU, HANJIE; WANG, JIAFEI

    2016-01-01

    Alantolactone is the active ingredient in frankincense, and is extracted from the dry root of elecampane. It has a wide variety of uses, including as an insect repellent, antibacterial, antidiuretic, analgesic and anticancer agent. In addition, alantolactone induces apoptosis of human cervical cancer cells, however, its mechanism of action remains to be elucidated. Therefore, the present study investigated whether alantolactone was able to induce apoptosis of human cervical cancer cells, and its potential mechanisms of action were analyzed. Treatment of HeLa cells with alantolactone (0, 10, 20, 30, 40, 50 and 60 µM) for 12 h significantly inhibited growth in a dose-dependent manner. Cells treated with 30 µM of alantolactone for 0, 3, 6 and 12 h demonstrated marked induction of apoptosis in a time-dependent manner. Treatment of HeLa cells with 30 µM of alantolactone for 0, 3, 6 and 12 h significantly induced the generation of reactive oxygen species (ROS) and inhibited glutathione (GSH) production in HeLa cells in a dose-dependent manner. Alantolactone additionally markedly inhibited the Bcl-2/Bax signaling pathway in HeLa cells. Therefore, administration of alantolactone induced apoptosis of human cervical cancer cells via ROS generation, GSH depletion and inhibition of the Bcl-2/Bax signaling pathway. PMID:27313767

  1. A novel member of the SAF (scaffold attachment factor)-box protein family inhibits gene expression and induces apoptosis

    PubMed Central

    Chan, Ching Wan; Lee, Youn-Bok; Uney, James; Flynn, Andrea; Tobias, Jonathan H.; Norman, Michael

    2007-01-01

    The SLTM [SAF (scaffold attachment factor)-like transcription modulator] protein contains a SAF-box DNA-binding motif and an RNA-binding domain, and shares an overall identity of 34% with SAFB1 {scaffold attachment factor-B1; also known as SAF-B (scaffold attachment factor B), HET [heat-shock protein 27 ERE (oestrogen response element) and TATA-box-binding protein] or HAP (heterogeneous nuclear ribonucleoprotein A1-interacting protein)}. Here, we show that SLTM is localized to the cell nucleus, but excluded from nucleoli, and to a large extent it co-localizes with SAFB1. In the nucleus, SLTM has a punctate distribution and it does not co-localize with SR (serine/arginine) proteins. Overexpression of SAFB1 has been shown to exert a number of inhibitory effects, including suppression of oestrogen signalling. Although SLTM also suppressed the ability of oestrogen to activate a reporter gene in MCF-7 breast-cancer cells, inhibition of a constitutively active β-galactosidase gene suggested that this was primarily the consequence of a generalized inhibitory effect on transcription. Measurement of RNA synthesis, which showed a particularly marked inhibition of [3H]uridine incorporation into mRNA, supported this conclusion. In addition, analysis of cell-cycle parameters, chromatin condensation and cytochrome c release showed that SLTM induced apoptosis in a range of cultured cell lines. Thus the inhibitory effects of SLTM on gene expression appear to result from generalized down-regulation of mRNA synthesis and initiation of apoptosis consequent upon overexpressing the protein. While indicating a crucial role for SLTM in cellular function, these results also emphasize the need for caution when interpreting phenotypic changes associated with manipulation of protein expression levels. PMID:17630952

  2. Isoliquiritigenin induces growth inhibition and apoptosis through downregulating arachidonic acid metabolic network and the deactivation of PI3K/Akt in human breast cancer

    SciTech Connect

    Li, Ying; Zhao, Haixia; Wang, Yuzhong; Zheng, Hao; Yu, Wei; Chai, Hongyan; Zhang, Jing; Falck, John R.; Guo, Austin M.; Yue, Jiang; Peng, Renxiu; Yang, Jing

    2013-10-01

    Arachidonic acid (AA)-derived eicosanoids and its downstream pathways have been demonstrated to play crucial roles in growth control of breast cancer. Here, we demonstrate that isoliquiritigenin, a flavonoid phytoestrogen from licorice, induces growth inhibition and apoptosis through downregulating multiple key enzymes in AA metabolic network and the deactivation of PI3K/Akt in human breast cancer. Isoliquiritigenin diminished cell viability, 5-bromo-2′-deoxyuridine (BrdU) incorporation, and clonogenic ability in both MCF-7 and MDA-MB-231cells, and induced apoptosis as evidenced by an analysis of cytoplasmic histone-associated DNA fragmentation, flow cytometry and hoechst staining. Furthermore, isoliquiritigenin inhibited mRNA expression of multiple forms of AA-metabolizing enzymes, including phospholipase A2 (PLA2), cyclooxygenases (COX)-2 and cytochrome P450 (CYP) 4A, and decreased secretion of their products, including prostaglandin E{sub 2} (PGE{sub 2}) and 20-hydroxyeicosatetraenoic acid (20-HETE), without affecting COX-1, 5-lipoxygenase (5-LOX), 5-lipoxygenase activating protein (FLAP), and leukotriene B{sub 4} (LTB{sub 4}). In addition, it downregulated the levels of phospho-PI3K, phospho-PDK (Ser{sup 241}), phospho-Akt (Thr{sup 308}), phospho-Bad (Ser{sup 136}), and Bcl-x{sub L} expression, thereby activating caspase cascades and eventually cleaving poly(ADP-ribose) polymerase (PARP). Conversely, the addition of exogenous eicosanoids, including PGE{sub 2}, LTB{sub 4} and a 20-HETE analog (WIT003), and caspase inhibitors, or overexpression of constitutively active Akt reversed isoliquiritigenin-induced apoptosis. Notably, isoliquiritigenin induced growth inhibition and apoptosis of MDA-MB-231 human breast cancer xenografts in nude mice, together with decreased intratumoral levels of eicosanoids and phospho-Akt (Thr{sup 308}). Collectively, these data suggest that isoliquiritigenin induces growth inhibition and apoptosis through downregulating AA metabolic

  3. Ilex latifolia Prevents Amyloid β Protein (25-35)-Induced Memory Impairment by Inhibiting Apoptosis and Tau Phosphorylation in Mice.

    PubMed

    Kim, Joo Youn; Lee, Hong Kyu; Jang, Ji Yeon; Yoo, Jae Kuk; Seong, Yeon Hee

    2015-12-01

    Ilex latifolia Thunb. (Aquifoliaceae), a Chinese bitter tea called "kudingcha," has been widely consumed as a health beverage and found to possess antioxidant, antidiabetic, antihypertensive, anti-inflammatory, and anti-ischemic activities. The aim of the present study was to investigate the neuroprotective effects of an ethanol extract of I. latifolia against amyloid β protein (Aβ)-induced memory impairment in mice and neurotoxicity in cultured rat cortical neurons. Memory impairment in mice was induced by intracerebroventricular injection of 15 nmol Aβ (25-35) and measured by the passive avoidance test and Morris water maze test. Chronic administration of I. latifolia (25-100 mg/kg, p.o.) significantly prevented Aβ (25-35)-induced memory loss. I. latifolia also prevented the decrease of glutathione concentrations, increased lipid peroxidation, expression of phosphorylated tau (p-tau), and changes in apoptosis-associated proteins in the memory-impaired mouse brain. Exposure of cultured cortical neurons to 10 μM Aβ (25-35) for 36 h induced neuronal apoptotic death. The neuronal cell death, elevation of intracellular Ca(2+) concentration, generation of reactive oxygen species, and expression of proapoptotic proteins caused by Aβ (25-35) in the cultured neurons were inhibited by treatment with I. latifolia (1-50 μg/mL). These results suggest that I. latifolia may have a possible therapeutic role in managing cognitive impairment associated with Alzheimer's disease. The underlying mechanism might involve the antiapoptotic effects mediated by antioxidant activity and inhibition of p-tau formation.

  4. Radioprotective effect of geraniin via the inhibition of apoptosis triggered by γ-radiation-induced oxidative stress.

    PubMed

    Kang, Kyoung Ah; Lee, In Kyung; Zhang, Rui; Piao, Mei Jing; Kim, Ki Cheon; Kim, Sang Young; Shin, Taekyun; Kim, Bum Joon; Lee, Nam Ho; Hyun, Jin Won

    2011-04-01

    The radioprotective effect of geraniin, a tannin compound isolated from Nymphaea tetragona Georgi var. (Nymphaeaceae), against γ-radiation-induced damage was investigated in Chinese hamster lung fibroblast (V79-4) cells. Geraniin recovered cell viability detected by MTT test and colony formation assay, which was compromised by γ-radiation, and reduced the γ-radiation-induced apoptosis by the inhibition of loss of the mitochondrial membrane potential. Geraniin protected cellular components (lipid membrane, cellular protein, and DNA) damaged by γ-radiation, which was detected by lipid peroxidation, protein carbonyl formation, and comet assay. Geraniin significantly reduced the level of intracellular reactive oxygen species generated by γ-radiation, which was detected using spectrofluorometer, flow cytometer, and confocal microscope after 2',7'-dichlorodihydrofluorescein diacetate staining. Geraniin normalized the superoxide dismutase and catalase activities, which were decreased by γ-radiation. These results suggest that geraniin protects cells against radiation-induced oxidative stress via enhancing of antioxidant enzyme activities and attenuating of cellular damage.

  5. Dicentrine Analogue-Induced G2/M Arrest and Apoptosis through Inhibition of Topoisomerase II Activity in Human Cancer Cells.

    PubMed

    Lin, Huei-Fang; Huang, Huey-Lan; Liao, Jyh-Fei; Shen, Chien-Chang; Huang, Ray-Ling

    2015-07-01

    Lindera megaphylla has been traditionally used as an antineoplastic and wound healing remedy. We previously demonstrated the antitumor effects of D-dicentrine, a natural aporphine alkaloid from the root of L. megaphylla. To generate analogues, series of phenanthrene alkaloids from D-dicentrine were synthesized by degradation with ethyl chloroformate in pyridine, base hydrolysis, and N-alkylation. In this study, we demonstrated that one of the synthesized D-dicentrine analogues (here after designated as analogue 1) exhibited more potent cytotoxic effects than D-dicentrine in colon adenocarcinoma, hepatoma, leukemia, and epidermoid carcinoma cells. We performed cell cycle and apoptotic analysis by flow cytometry, an apoptotic DNA detection ELISA assay, and topoisomerase II activity by the kinetoplast DNA concatenation assay for studying their cytotoxic mechanisms. We found that both D-dicentrine and analogue 1 induced apoptosis and G2/M arrest in HL-60 leukemia cells. The percentage of apoptotic cells induced by analogue 1 was 4.5-fold higher than that induced by D-dicentrine as evident from measuring the amount of histone-bound DNA fragments. Moreover, we found that analogue 1 was 28-fold more potent than D-dicentrine for inhibition of topoisomerase II activity by the kinetoplast DNA concatenation assay. Our findings indicate that D-dicentrine analogue 1 is very promising as a potential antitumor agent for future study.

  6. Epoxyeicosatrienoic acids induce growth inhibition and calpain/caspase-12 dependent apoptosis in PDGF cultured 3T6 fibroblast.

    PubMed

    Nieves, Diana; Moreno, Juan J

    2007-11-01

    Previous studies have demonstrated that arachidonic acid (AA) metabolites released by the cyclooxygenase pathway is involved in serum-induced 3T6 fibroblast cycle progression and proliferation. However, these results also suggest that other AA cascade pathways might be involved. Recently, we also described the role of hydroxyeicosatetraenoic acids, which are produced by cytochrome P450 monooxygenases (CYP), in 3T6 fibroblast growth. AA can be also metabolized by the epoxygenase activity of CYP-producing epoxyeicosatrienoic acids (EETs). Finally, the cytosolic epoxide hydrolases catalyze the hydration of the EETs, transforming them into dihydroxyeicosatetraenoic acids (DHETEs). In this work, we have studied the role of the EETs/DHETEs on 3T6 fibroblasts growth. Our results show that PDGF stimulates 3T6 fibroblast proliferation and [3H]thymidine incorporation, while the addition of 5,6-EET, 8,9-EET, 11,12-EET or 14,15-EET (0.1-1 microM) inhibit these processes. Furthermore, 5,6-DHETE and 11,12-DHETE (0.1-1 microM) also inhibit cell proliferation and DNA synthesis. Interestingly, this growth inhibition was correlated with an induction of apoptosis. Thus, we observed that in the presence of PDGF, EETs or DHETEs (0.1-1 microM) induce phosphatidylserine externalization (as measured by annexin V-binding) and DNA fragmentation (as quantified using a TUNEL assay). Our results show that calpain, as well as caspase-12 and caspase-3, are involved in these events. Therefore, EETs and DHETEs have anti-proliferative and pro-apoptotic effects on PDGF-stimulated 3T6 fibroblasts.

  7. Combined inhibition of Hsp90 and heme oxygenase-1 induces apoptosis and endoplasmic reticulum stress in melanoma.

    PubMed

    Barbagallo, Ignazio; Parenti, Rosalba; Zappalà, Agata; Vanella, Luca; Tibullo, Daniele; Pepe, Francesco; Onni, Toniangelo; Li Volti, Giovanni

    2015-10-01

    Heat shock proteins are ubiquitous molecular chaperones involved in post-translational folding, stability, activation and maturation of many proteins that are essential mediators of signal transduction and cell cycle progression. Heat shock protein 90 (Hsp90) has recently emerged as an attractive therapeutic target in cancer treatment since it may act as a key regulator of various oncogene products and cell-signaling molecules. Heme oxygenase-1 (HO-1; also known as Hsp32) is an inducible enzyme participating in heme degradation and involved in oxidative stress resistance. Recent studies indicate that HO-1 activation may play a role in tumor development and progression. In the present study we investigated the chemotherapic effects of combining an Hsp90 inhibitor (NMS E973) and an HO-1 inhibitor (SnMP) on A375 melanoma cells. NMS E973 treatment was able to reduce cell viability and induce endoplasmic reticulum (ER) stress (i.e. Ire1α, ERO1, PDI, BIP and CHOP). Interestingly, no significant effect was observed in reactive oxygen species (ROS) formation. Finally, NMS E973 treatment resulted in a significant HO-1 overexpression, which in turn serves as a possible chemoresistance molecular mechanism. Interestingly, the combination of NMS E973 and SnMP produced an increase of ROS and reduced cell viability compared to NMS E973 treatment alone. The inhibitors combination exhibited higher ER stress, apoptosis as evidenced by bifunctional apoptosis regulator (BFAR) mRNA expression and lower phosphorylation of Akt when compared to NMS E973 alone. In conclusion, these data suggest that HO-1 inhibition potentiates NMS E973 toxicity and may be exploited as a strategy for melanoma treatment.

  8. Aloe-emodin modulates PKC isozymes, inhibits proliferation, and induces apoptosis in U-373MG glioma cells.

    PubMed

    Acevedo-Duncan, Mildred; Russell, Christopher; Patel, Sapna; Patel, Rekha

    2004-12-20

    Aloe-emodin (1,8-dihydroy-3-[hydroxymethyl]-anthraquione) purified from Aloe vera leaves has been reported to have antitumor activity. The objectives of our research were to determine how aloe-emodin regulates the cell cycle, cell proliferation and protein kinase C (PKC) during glioma growth and development. To establish the cell cycle effects of aloe-emodin on brain cells [transformed glia cell line (SVG) and human glioma U-373MG cell line (U-373MG)], cells were treated with either dimethylsulfoxide (DMSO; control) or aloe-emodin (40 microM). Results from flow cytometry demonstrated that aloe-emodin delayed the number of cells entering and exiting DNA synthesis (S) phase in both SVG and U-373MG cells indicating that aloe-emodin may inhibit S phase progression. Assessment of cell viability demonstrated that SVG and U-373MG glioma cell were highly sensitive to aloe-emodin. The aloe-emodin-induced decreased proliferation was sustained at 48-96 h. A PKC activity assay was quantified to establish the role of PKC in aloe-emodin's mode of action. Exposure of SVG and U-373MG glioma cells to aloe-emodin suppressed PKC activity and reduced the protein content of most of the PKC isozymes. We determined that cancer growth inhibition by aloe-emodin was due to apoptosis (i.e., programmed cell death). Taken together, these results support the hypothesis that aloe-emodin represents a novel antitumor chemotherapeutic drug.

  9. Curcumin Inhibits Gastric Carcinoma Cell Growth and Induces Apoptosis by Suppressing the Wnt/β-Catenin Signaling Pathway

    PubMed Central

    Zheng, Ruzhen; Deng, Qinghua; Liu, Yuehua; Zhao, Pengjun

    2017-01-01

    Background Curcumin has well-known, explicit biological anti-tumor properties. The Wnt/β-catenin signaling pathway plays a central role in tumor cell proliferation and curcumin can regulate the Wnt/β-catenin signaling pathway of several carcinomas. The aim of this study was to investigate the impact of curcumin on the Wnt/β-catenin signaling pathway in human gastric cancer cells. Material/Methods We used 3 gastric cancer cell lines: SNU-1, SNU-5, and AGS. Research methods used were MTT assay, flow cytometry, clonogenic assay, annexin V/PI method, Western blotting analysis, tumor formation assay, and in vivo in the TUNEL assay. Results Curcumin markedly impaired tumor cell viability and induced apoptosis in vitro. Curcumin significantly suppressed the levels of Wnt3a, LRP6, phospho-LRP6, β-catenin, phospho-β-catenin, C-myc, and survivin. Xenograft growth in vivo was inhibited and the target genes of Wnt/β-catenin signaling were also reduced by curcumin treatment. Conclusions Curcumin exerts anti-proliferative and pro-apoptotic effect in gastric cancer cells and in a xenograft model. Inhibition of the Wnt/β-catenin signaling pathway and the subsequently reduced expression of Wnt target genes show potential as a newly-identified molecular mechanism of curcumin treatment. PMID:28077837

  10. Compound 13, an α1-selective small molecule activator of AMPK, inhibits Helicobacter pylori-induced oxidative stresses and gastric epithelial cell apoptosis

    SciTech Connect

    Zhao, Hangyong; Zhu, Huanghuang; Lin, Zhou; Lin, Gang; Lv, Guoqiang

    2015-08-07

    Half of the world's population experiences Helicobacter pylori (H. pylori) infection, which is a main cause of gastritis, duodenal and gastric ulcer, and gastric cancers. In the current study, we investigated the potential role of compound 13 (C13), a novel α1-selective small molecule activator of AMP-activated protein kinase (AMPK), against H. pylori-induced cytotoxicity in cultured gastric epithelial cells (GECs). We found that C13 induced significant AMPK activation, evidenced by phosphorylation of AMPKα1 and ACC (acetyl-CoA carboxylase), in both primary and transformed GECs. Treatment of C13 inhibited H. pylori-induced GEC apoptosis. AMPK activation was required for C13-mediated GEC protection. Inhibition of AMPK kinase activity by the AMPK inhibitor Compound C, or silencing AMPKα1 expression by targeted-shRNAs, alleviated C13-induced GEC protective activities against H. pylori. Significantly, C13 inhibited H. pylori-induced reactive oxygen species (ROS) production in GECs. C13 induced AMPK-dependent expression of anti-oxidant gene heme oxygenase (HO-1) in GECs. Zinc protoporphyrin (ZnPP) and tin protoporphyrin (SnPP), two HO-1 inhibitors, not only suppressed C13-mediated ROS scavenging activity, but also alleviated its activity in GECs against H. pylori. Together, these results indicate that C13 inhibits H. pylori-induced ROS production and GEC apoptosis through activating AMPK–HO–1 signaling. - Highlights: • We synthesized compound 13 (C13), a α1-selective small molecule AMPK activator. • C13-induced AMPK activation requires α1 subunit in gastric epithelial cells (GECs). • C13 enhances Helicobacter pylori-induced pro-survival AMPK activation to inhibit GEC apoptosis. • C13 inhibits H. pylori-induced reactive oxygen species (ROS) production in GECs. • AMPK-heme oxygenase (HO-1) activation is required for C13-mediated anti-oxidant activity.

  11. Beta1 integrin inhibits apoptosis induced by cyclic stretch in annulus fibrosus cells via ERK1/2 MAPK pathway.

    PubMed

    Zhang, Kai; Ding, Wei; Sun, Wei; Sun, Xiao-jiang; Xie, You-zhuan; Zhao, Chang-qing; Zhao, Jie

    2016-01-01

    Low back pain is associated with intervertebral disc degeneration (IVDD) due to cellular loss through apoptosis. Mechanical factors play an important role in maintaining the survival of the annulus fibrosus (AF) cells and the deposition of extracellular matrix. However, the mechanisms that excessive mechanical forces lead to AF cell apoptosis are not clear. The present study was to look for how AF cells sense mechanical changes. In vivo experiments, the involvement of mechanoreceptors in apoptosis was examined by RT-PCR and/or immunoblotting in the lumbar spine of rats subjected to unbalanced dynamic and static forces. In vitro experiments, we investigated apoptotic signaling pathways in untransfected and transfected AF cells with the lentivirus vector for rat β1 integrin overexpression after cyclic stretch. Apoptosis in AF cells was assessed using flow cytometry, Hoechst 33258 nuclear staining. Western blotting was used to analyze expression of β1 integrin and caspase-3 and ERK1/2 MAPK signaling molecules. In the rat IVDD model, unbalanced dynamic and static forces induced apoptosis of disc cells, which corresponded to decreased expression of β1 integrin. Cyclic stretch-induced apoptosis in rat AF cells correlated with the activation of caspase-3 and with decreased levels of β1 integrin and the phosphorylation levels of ERK1/2 activation level. However, the overexpression of β1 integrin in AF cells ameliorated cyclic stretch-induced apoptosis and decreased caspase-3 activation. Furthermore, ERK1/2-specific inhibitor promotes apoptosis in vector β1-infected AF cells. These results suggest that the disruption of β1 integrin signaling may underlie disc cell apoptosis induced by mechanical stress. Further work is necessary to fully elucidate the pathophysiological mechanisms that underlie IVDD caused by unbalanced dynamic and static forces.

  12. Genistein Induces Apoptosis and Inhibits Proliferation of HT29 Colon Cancer Cells

    PubMed Central

    Shafiee, Gholamreza; Saidijam, Massoud; Tavilani, Heidar; Ghasemkhani, Neda; Khodadadi, Iraj

    2016-01-01

    Soybean isoflavone genistein has multiple anticancer properties and its pro-apoptotic and anti-proliferative effects have been studied in different cancer cells. However, the mechanisms of action of genistein and its molecular targets on human colon cells have not been fully elucidated. Therefore, caspase-3 and p38 mitogen-activated protein kinase (p38 MAPK) as the main therapeutic targets were investigated in this study at both gene expression and protein levels in HT29 colon cancer cells. The caspase-3 and p38 MAPK gene expression levels were examined by real time PCR whereas flow cytometry technique was performed to determine their intracellular protein levels. The caspase-3 enzyme activity was obtained by colorimetric method while the gelatinase activity of matrix metalloproteinase-2 (MMP2) was determined by zymography. In addition, MTT test, wound healing assay and clonogenic assay were carried out to determine the effect of genistein on HT29 cell viability, migration, and proliferation, respectively. Genistein induced apoptotic death in HT29 cells through activation of caspase-3 pathway at the transcriptional, protein, and enzymatic levels. Moreover, genistein inhibited the proliferation of HT29 cells by reducing of both p38 MAPK gene expression and its active phosphorylated protein level. Also, we showed that genistein strongly suppressed the metastatic potency of HT29 colon cancer cells via the reduction of MMP2 activity. Based on the results of this study, we conclude that genistein may exhibit its anticancer properties on HT29 colon cancer cells by modulating caspase-3 and p38 MAPK pathway at different transcriptional and protein levels. PMID:27942504

  13. Ethacrynic acid butyl-ester induces apoptosis in leukemia cells through a hydrogen peroxide mediated pathway independent of glutathione S-transferase P1-1 inhibition.

    PubMed

    Wang, Rui; Li, Chunmin; Song, Dandan; Zhao, Guisen; Zhao, Linxiang; Jing, Yongkui

    2007-08-15

    Ethacrynic acid (EA), a glutathione S-transferase inhibitor and diuretic agent, inhibits cell growth and induces apoptosis in cancer cells. To improve the activities, the structure of EA has been modified, and it has been shown that EA esters had an increased cell growth inhibitory ability compared with nonesterified analogue. EA butyl-ester (EABE) was synthesized, and its apoptosis induction ability was studied. The efficacy of EABE was compared with that of EA, and the mechanisms of action were studied in HL-60 leukemia cells. EABE exhibited greater cell growth inhibitory and apoptosis induction abilities than did EA. EABE-induced apoptosis in HL-60 cells correlated with increased levels of reactive oxygen species, the death receptor 5 (DR5), and caspase activation and decreased levels of the mitochondrial membrane potential. Pretreatment with antioxidants, either N-acetylcysteine or catalase, completely blocked EABE-induced apoptosis, H2O2 accumulation, and up-regulation of DR5 levels. RG19, a subclone of Raji cells stably transfected with a GSTpi expression vector, and K562 cells with high endogenous GSTP1-1 activity were less sensitive to EABE-induced apoptosis. EABE was more rapidly taken up than EA by HL-60 cells as determined by high-performance liquid chromatography (HPLC) measurements of intracellular concentrations. These results suggest that (a) H2O2 production is a mediator of EABE and EA-induced apoptosis; (b) GSTP1-1 plays a negative role in EABE and EA-induced apoptosis; and (c) the activity of EABE is greater than EA due to its more rapid entry into cells.

  14. SIRT1 inhibits TNF-α-induced apoptosis of vascular adventitial fibroblasts partly through the deacetylation of FoxO1.

    PubMed

    Wang, Weirong; Yan, Chunfang; Zhang, Jiye; Lin, Rong; Lin, Qinqin; Yang, Lina; Ren, Feng; Zhang, Jianfeng; Ji, Meixi; Li, Yanxiang

    2013-06-01

    Sirtuin 1 (SIRT1), a NAD(+)-dependent class III histone deacetylase, participates in regulating cellular apoptosis, senescence and metabolism by deacetylating histones and multiple transcription factors. In this study, we aimed to determine the effect of SIRT1 on the apoptosis of vascular adventitial fibroblasts (VAFs) and related signaling pathways. SIRT1 was found in the nucleus of VAFs and translocated into the cytoplasm in response to tumor necrosis factor-α (TNF-α). Moreover, SIRT1 protein expression was reduced in VAFs stimulated with TNF-α. In addition, TNF-α increased the apoptosis of VAFs. Activation of SIRT1 by resveratrol (RSV) or overexpression of SIRT1 attenuated TNF-α-induced VAF apoptosis by decreasing the percentage of apoptotic cells and cleaved caspase-3 protein expression and increasing the Bcl-2/Bax ratio. In contrast, inhibition of SIRT1 by sirtinol/nicotinamide or knockdown of SIRT1 enhanced apoptosis of VAFs. On the other hand, knockdown of FoxO1 reduced TNF-α-induced VAF apoptosis. SIRT1 interacted with FoxO1 in VAFs by the co-immunoprecipitation assay. Further study showed that RSV or SIRT1 overexpression decreased acetylated-FoxO1 (Ac-FoxO1) protein expression in VAFs stimulated with TNF-α. Knockdown of SIRT1 resulted in an increase in Ac-FoxO1 protein expression. Taken together, these findings indicate that SIRT1 inhibits the apoptosis of VAFs, whereas FoxO1 promotes VAF apoptosis. Furthermore, the inhibitory effect of SIRT1 on VAF apoptosis is partly mediated by the deacetylation of FoxO1.

  15. Small compound inhibitors of basal glucose transport inhibit cell proliferation and induce apoptosis in cancer cells via glucose-deprivation-like mechanisms.

    PubMed

    Liu, Yi; Zhang, Weihe; Cao, Yanyan; Liu, Yan; Bergmeier, Stephen; Chen, Xiaozhuo

    2010-12-08

    Cancer cells depend heavily on glucose as both energy and biosynthesis sources and are found to upregulate glucose transport and switch their main energy supply pathway from oxidative phosphorylation to glycolysis. These molecular and metabolic changes also provide targets for cancer treatment. Here we report that novel small molecules inhibited basal glucose transport and cell proliferation, and induced apoptosis in lung and breast cancer cells without affecting much their normal cell counterparts. Cancer cells survived the compound treatment lost their capability to proliferate. Mechanistic study indicates that the cancer cell inhibition by the test compounds has a component of apoptosis and the induced apoptosis was p53-independent and caspase 3-dependent, similar to those resulted from glucose deprivation. Compound treatment also led to cell cycle arrest in G1/S phase. The inhibition of cancer cell growth was partially relieved when additional glucose was supplied to cells, suggesting that the inhibition was due to, at least in part, the inhibition of basal glucose transport. When used in combination, the test compounds demonstrated synergistic effects with anticancer drugs cisplatin or paclitaxel in inhibition of cancer cell growth. All these results suggest that these glucose transport inhibitors mimic glucose deprivation and work through inhibiting basal glucose transport. These inhibitors have the potential to complement and replace traditional glucose deprivation, which cannot be used in animals, as new tools to study the effects of glucose transport and metabolism on cancer and normal cells.

  16. Semisynthetic homoharringtonine induces apoptosis via inhibition of protein synthesis and triggers rapid myeloid cell leukemia-1 down-regulation in myeloid leukemia cells.

    PubMed

    Tang, Ruoping; Faussat, Anne-Marie; Majdak, Patricia; Marzac, Christophe; Dubrulle, Sabine; Marjanovic, Zora; Legrand, Ollivier; Marie, Jean-Pierre

    2006-03-01

    Semisynthetic homoharringtonine (ssHHT) is now being evaluated in phase II clinical trials for the treatment of chronic myelogenous leukemia and acute myelogenous leukemia patients. Here, we examined the mechanism of the apoptosis induced by ssHHT in myeloid leukemia cells. First, we have shown that ssHHT induces apoptosis in HL60 and HL60/MRP cell lines in a time- and dose-dependent manner, and independently of the expression of Bax. The decrease of mitochondrial membrane potential and the release of cytochrome c were observed in the apoptotic cells induced by ssHHT. To unveil the relationship between ssHHT and the mitochondrial disruption, we have shown that ssHHT decreased myeloid cell leukemia-1 (Mcl-1) expression and induced Bcl-2 cleavage in HL60 and HL60/MRP cell lines. The Bcl-2 cleavage could be inhibited by the Z-VAD.fmk caspase inhibitor. However, Mcl-1 turnover was very rapid and occurred before caspase activation. The Mcl-1 turnover was only induced by ssHHT and cycloheximide, but not by daunorubicin and cytosine arabinoside, and could be restored by proteasome inhibitors. Second, we confirmed that ssHHT rapidly induced massive apoptosis in acute myelogenous leukemia patient cells. We have also confirmed the release of cytochrome c and a rapid turnover of Mcl-1 in these patient cells, taking place only in apoptotic cells induced by ssHHT but not in cells undergoing spontaneous apoptosis. Finally, we have shown that ssHHT inhibits protein synthesis in both cell line and patient cells. We suggest that the inhibition of protein synthesis and resulting Mcl-1 turnover play a key role in the apoptosis induced by ssHHT. Our results encourage further clinical trials for the use of ssHHT in acute myelogenous leukemia.

  17. A20 inhibits tumor necrosis factor (TNF) alpha-induced apoptosis by disrupting recruitment of TRADD and RIP to the TNF receptor 1 complex in Jurkat T cells.

    PubMed

    He, Kai-Li; Ting, Adrian T

    2002-09-01

    Tumor necrosis factor receptor 1 (TNFR1) can trigger distinct signaling pathways leading to either the activation of NF-kappaB transcription factors or apoptosis. NF-kappaB activation results in the expression of antiapoptotic genes that inhibit the apoptosis pathway that is activated in parallel. However, the molecular mechanism of this inhibition remains poorly characterized. We have isolated a Jurkat T-cell mutant that exhibits enhanced sensitivity to TNF-induced apoptosis as a result of a deficiency in I-kappaB kinase gamma (IKKgamma)/NEMO, an essential component of the IKK complex and NF-kappaB pathway. We show here that the zinc finger protein A20 is an NF-kappaB-inducible gene that can protect the IKKgamma-deficient cells from TNF-induced apoptosis by disrupting the recruitment of the death domain signaling molecules TRADD and RIP to the receptor signaling complex. Our study, together with reports on the role of other antiapoptotic proteins such as c-FLIP and c-IAP, suggests that, in order to ensure an effective shutdown of the apoptotic pathway, TNF induces multiple NF-kappaB-dependent genes that inhibit successive steps in the TNFR1 death signaling pathway.

  18. Puerarin inhibits proliferation and induces apoptosis in human glioblastoma cell lines

    PubMed Central

    Yang, Ji-An; Li, Ji-Qiang; Shao, Ling-Min; Yang, Qian; Liu, Bao-Hui; Wu, Ting-Feng; Wu, Peng; Yi, Wei; Chen, Qian-Xue

    2015-01-01

    Puerarin has been widely used in clinical treatment and experiment research and is considered to exert an anticancer effect recently. The present study investigated the anticancer activity of puerarin in U251 and U87 human glioblastoma cells. The cells were treated with puerarin at various concentrations for different times. Cell viability and cell proliferation were detected by cell counting kit-8 (CCK-8) assay and 5-ethynyl-2’-deoxyuridine (EdU) staining respectively. Cell cycle and apoptosis were measured separately with PI staining and Annexin V-FITC/PI double staining method by flow cytometry. DNA damage of glioblastoma cells caused by puerarin exposure was evaluated by γ-H2AX foci detection, and the expressions of p-AKT, caspase-3 and apoptosis-related proteins were detected by Western blotting after puerarin treatment. Cell viability and proliferation of glioblastoma cells treated with puerarin were significantly lower than that of the control group; the apoptosis rate increased obviously compared to the control group. Puerarin significantly decreased the proportion at G1 phase of cell cycling accompanied by increased populations at the S and G2/M phases in both cell lines. At the same time, DNA damage level of puerarin treated cells was significantly higher than that in the control cells. Moreover, puerarin treatment suppressed the expression of p-Akt and Bcl-2 and promoted the expression of Bax and cleaved caspase-3 in U251 cells. These findings indicate that puerarin exerts antitumor effects both in U251 and U87 cells. PMID:26309712

  19. Inhibition of PDE5 by sulindac sulfide selectively induces apoptosis and attenuates oncogenic Wnt/β-catenin mediated transcription in human breast tumor cells

    PubMed Central

    Tinsley, Heather N.; Gary, Bernard D.; Keeton, Adam B.; Lu, Wenyan; Li, Yonghe; Piazza, Gary A.

    2011-01-01

    Nonsteroidal anti-inflammatory drugs (NSAIDs) such as sulindac sulfide (SS) display promising antineoplastic properties, but toxicities resulting from cyclooxygenase (COX) inhibition limit their clinical use. While COX inhibition is responsible for the anti-inflammatory activity of SS, recent studies suggest that phosphodiesterase (PDE) 5 inhibition and activation of cGMP signaling are closely associated with its ability to induce apoptosis of tumor cells. However, the underlying mechanisms responsible for apoptosis induction, factors that influence sensitivity of tumor cells to SS, and the importance of PDE5 for breast tumor cell growth have not been established. Here we show that SS can induce apoptosis of breast tumor cells, which predominantly rely on PDE5 for cGMP hydrolysis, but not normal mammary epithelial cells, which rely on PDE isozymes other than PDE5 for cGMP hydrolysis. Inhibition of PDE5 and activation of PKG by SS was associated with increased β-catenin phosphorylation, decreased β-catenin mRNA and protein levels, reduced β-catenin nuclear localization, decreased Tcf/Lef promoter activity, and decreased expression of Wnt/β-catenin regulated proteins. Suppression of PDE5 with siRNA or known PDE5 inhibitors was sufficient to selectively induce apoptosis and attenuate β-catenin mediated transcription in breast tumor cells with minimal effects on normal mammary epithelial cells. These findings provide evidence that SS induces apoptosis of breast tumor cells through a mechanism involving inhibition of PDE5 and attenuation of oncogenic Wnt/β-catenin mediated transcription. We conclude that PDE5 represents a novel molecular target for the discovery of safer and more efficacious drugs for breast cancer chemoprevention. PMID:21505183

  20. Inhibition of PDE5 by sulindac sulfide selectively induces apoptosis and attenuates oncogenic Wnt/β-catenin-mediated transcription in human breast tumor cells.

    PubMed

    Tinsley, Heather N; Gary, Bernard D; Keeton, Adam B; Lu, Wenyan; Li, Yonghe; Piazza, Gary A

    2011-08-01

    Nonsteroidal anti-inflammatory drugs (NSAID) such as sulindac sulfide (SS) display promising antineoplastic properties, but toxicities resulting from COX inhibition limit their clinical use. Although COX inhibition is responsible for the anti-inflammatory activity of SS, recent studies suggest that phosphodiesterase (PDE) 5 inhibition and activation of cyclic guanosine monophosphate (cGMP) signaling are closely associated with its ability to induce apoptosis of tumor cells. However, the underlying mechanisms responsible for apoptosis induction, factors that influence sensitivity of tumor cells to SS, and the importance of PDE5 for breast tumor cell growth have not been established. Here we show that SS can induce apoptosis of breast tumor cells, which predominantly rely on PDE5 for cGMP hydrolysis but not normal mammary epithelial cells, which rely on PDE isozymes other than PDE5 for cGMP hydrolysis. Inhibition of PDE5 and activation of protein kinase G (PKG) by SS was associated with increased β-catenin phosphorylation, decreased β-catenin mRNA and protein levels, reduced β-catenin nuclear localization, decreased T-cell factor/lymphoid enhancer factor (Tcf/Lef) promoter activity, and decreased expression of Wnt/β-catenin-regulated proteins. Suppression of PDE5 with siRNA or known PDE5 inhibitors was sufficient to selectively induce apoptosis and attenuate β-catenin-mediated transcription in breast tumor cells with minimal effects on normal mammary epithelial cells. These findings provide evidence that SS induces apoptosis of breast tumor cells through a mechanism involving inhibition of PDE5 and attenuation of oncogenic Wnt/β-catenin-mediated transcription. We conclude that PDE5 represents a novel molecular target for the discovery of safer and more efficacious drugs for breast cancer chemoprevention.

  1. Thymoquinone Inhibits the CXCL12-Induced Chemotaxis of Multiple Myeloma Cells and Increases Their Susceptibility to Fas-Mediated Apoptosis

    PubMed Central

    Badr, Gamal; Lefevre, Eric A.; Mohany, Mohamed

    2011-01-01

    In multiple myeloma (MM), malignant plasma cells reside in the bone marrow, where they accumulate in close contact with stromal cells. The mechanisms responsible for the chemotaxis of malignant plasma cells are still poorly understood. Thus, we investigated the mechanisms involved in the chemotaxis of MDN and XG2 MM cell lines. Both cell lines strongly expressed CCR9, CXCR3 and CXCR4 chemokine receptors but only migrated toward CXCL12. Activation of CXCR4 by CXCL12 resulted in the association of CXCR4 with CD45 and activation of PLCβ3, AKT, RhoA, IκBα and ERK1/2. Using siRNA-silencing techniques, we showed CD45/CXCR4 association is essential for CXCL12-induced migration of MM cells. Thymoquinone (TQ), the major active component of the medicinal herb Nigella sativa Linn, has been described as a chemopreventive and chemotherapeutic compound. TQ treatment strongly inhibited CXCL12-mediated chemotaxis in MM cell lines as well as primary cells isolated from MM patients, but not normal PBMCs. Moreover, TQ significantly down-regulated CXCR4 expression and CXCL12-mediated CXCR4/CD45 association in MM cells. Finally, TQ also induced the relocalization of cytoplasmic Fas/CD95 to the membrane of MM cells and increased CD95-mediated apoptosis by 80%. In conclusion, we demonstrate the potent anti-myeloma activity of TQ, providing a rationale for further clinical evaluation. PMID:21912642

  2. Inhibition of gap junction intercellular communication is involved in silica nanoparticles-induced H9c2 cardiomyocytes apoptosis via the mitochondrial pathway

    PubMed Central

    Du, Zhong-jun; Cui, Guan-qun; Zhang, Juan; Liu, Xiao-mei; Zhang, Zhi-hu; Jia, Qiang; Ng, Jack C; Peng, Cheng; Bo, Cun-xiang; Shao, Hua

    2017-01-01

    Gap junction intercellular communication (GJIC) between cardiomyocytes is essential for synchronous heart contraction and relies on connexin-containing channels. Connexin 43 (Cx43) is a major component involved in GJIC in heart tissue, and its abnormal expression is closely associated with various cardiac diseases. Silica nanoparticles (SNPs) are known to induce cardiovascular toxicity. However, the mechanisms through which GJIC plays a role in cardiomyocytes apoptosis induced by SNPs remain unknown. The aim of the present study is to determine whether SNPs-decreased GJIC promotes apoptosis in rat cardiomyocytes cell line (H9c2 cells) via the mitochondrial pathway using CCK-8 Kit, scrape-loading dye transfer technique, Annexin V/PI double-staining assays, and Western blot analysis. The results showed that SNPs elicited cytotoxicity in H9c2 cells in a time- and concentration-dependent manner. SNPs also reduced GJIC in H9c2 cells in a concentration-dependent manner through downregulation of Cx43 and upregulation of P-Cx43. Inhibition of gap junctions by gap junction blocker carbenoxolone disodium resulted in decreased survival and increased apoptosis, whereas enhancement of the gap junctions by retinoic acid led to enhanced survival but decreased apoptosis. Furthermore, SNPs-induced apoptosis through the disrupted functional gap junction was correlated with abnormal expressions of the proteins involved in the mitochondrial pathway-related apoptosis such as Bcl-2/Bax, cytochrome C, Caspase-9, and Caspase-3. Taken together, our results provide the first evidence that SNPs-decreased GJIC promotes apoptosis in cardiomyocytes via the mitochondrial pathway. In addition, downregulation of GJIC by SNPs in cardiomyocytes is mediated through downregulation of Cx43 and upregulation of P-Cx43. These results suggest that in rat cardiomyocytes cell line, GJIC plays a protective role in SNPs-induced apoptosis and that GJIC may be one of the targets for SNPs-induced biological

  3. The flavonoid quercetin induces apoptosis and inhibits JNK activation in intimal vascular smooth muscle cells

    SciTech Connect

    Perez-Vizcaino, Francisco . E-mail: fperez@med.ucm.es; Bishop-Bailley, David; Lodi, Federica; Duarte, Juan; Cogolludo, Angel; Moreno, Laura; Bosca, Lisardo; Mitchell, Jane A.; Warner, Timothy D.

    2006-08-04

    Quercetin, the most abundant dietary flavonol, exerts vasodilator, anti-hypertensive, and anti-atherogenic effects and reduces the vascular remodelling associated with elevated blood pressure. Here, we have compared the effects of quercetin in intimal- and medial-type rat vascular smooth muscle cells (VSMC) in culture. After 48 h, quercetin reduced the viability of a polyclonal intimal-type cell line derived from neonatal aorta but not of a medial-type cell line derived from adult aorta. These differential effects were similar in both proliferating and quiescent VSMC. Quercetin also preferentially reduced the viability of intimal-type over medial-type VSMC in primary cultures derived from balloon-injured carotid arteries. The effects of quercetin on cell viability were mainly dependent upon induction of apoptosis, as demonstrated by nuclear condensation and fragmentation, and were unrelated to PPAR{gamma}, pro-oxidant effects or nitric oxide. The expression of MAPKs (ERK, p38, and JNK) and ERK phosphorylation were not different between intimal- and medial-type VSMC. p38 phosphorylation was negligible in both cell types. Medial-type showed a weak JNK phosphorylation while this was markedly increased in intimal-type cells. Quercetin reduced JNK phosphorylation but had no consistent effect on ERK phosphorylation. In conclusion, quercetin preferentially produced apoptosis in intimal-type compared to medial-type VSMC. This might play a role in the anti-atherogenic and anti-hypertensive effects of quercetin.

  4. Ursodeoxycholic acid (UDCA) can inhibit deoxycholic acid (DCA)-induced apoptosis via modulation of EGFR/Raf-1/ERK signaling in human colon cancer cells.

    PubMed

    Im, Eunok; Martinez, Jesse D

    2004-02-01

    Ursodeoxycholic acid (UDCA), a hydrophilic bile acid, is known as a cytoprotective agent. UDCA prevents apoptosis induced by a variety of stress stimuli including cytotoxic bile acids such as deoxycholic acid (DCA). Here we examined the molecular mechanism by which UDCA can antagonize DCA-induced apoptosis in human colon cancer cells. UDCA pretreatment decreases the number of apoptotic cells caused by exposure to DCA and UDCA. Further studies of the signaling pathway showed that UDCA pretreatment suppressed DNA binding activity of activator protein-1 and this was accompanied by downregulation of both extracellular signal-regulated kinase (ERK) and Raf-1 kinase activities stimulated by exposure to DCA. DCA was also found to activate epidermal growth factor receptor (EGFR) activity and UDCA inhibited this. Collectively, these findings suggest that the inhibitory effect of UDCA in DCA-induced apoptosis is partly mediated by modulation of EGFR/Raf-1/ERK signaling.

  5. Triptolide inhibits cell growth and GRP78 protein expression but induces cell apoptosis in original and radioresistant NPC cells

    PubMed Central

    Lv, Wuwu; Lai, Chen; Chen, Zhikang; Wang, Ran; Long, Xueying; Feng, Xueping

    2016-01-01

    The radioresistance is the key factor to hamper curative effect and survival of nasopharyngeal carcinoma (NPC) patients. Nature triptolide (TPL) has been found to circumvent drug-resistant effect of cancer, but its effect on NPC radioresistance has been rarely studied. In the present study, the 10 Gy-resistant CNE2 subclones (CNE2-SR) were used as a NPC radioresistant model. The IC50 of TPL in CNE2 and CNE2-SR cells was measured by MTT assay, cell cycle was analyzed by flow cytometry, and protein expression was examined by western blot. Our data showed that TPL treatment decreased the percentage of viable cells, and IC50 value in CNE2 and CNE2-SR cells was 23.6 ± 1.41 nmol/L and 31.2 ± 1.16 nmol/L, respectively. Six Gy was a moderate dosage of X-ray for CNE2, and 25 nM TPL was close to IC50 value of CNE2 and CNE2-SR. Six Gy X-ray and/or 25 nM TPL significantly inhibited tumor growth in nude mice. Furthermore, 6 Gy X-ray and/or 25 nM TPL significantly inhibited cell growth and induced cell apoptosis and M/G2 phase arrest in CNE2 and CNE2-SR cells. Moreover, TPL treatment significantly inhibited the expression of GRP78 protein in CNE2 and CNE2-SR cells. These results suggest that TPL may serve as a potential radiosensitizer agent for NPC treatment. PMID:27391061

  6. Decreased TRPM7 inhibits activities and induces apoptosis of bladder cancer cells via ERK1/2 pathway

    PubMed Central

    Liu, Tongzu; Wang, Gang; Qian, Guofeng; Cao, Tingting; Guan, Xinyuan; Dan, Hancai; Xiao, Yu; Wang, Xinghuan

    2016-01-01

    Transient receptor potential melastatin 7 (TRPM7) functions as a Mg2+/Ca2+-permeable channel fused with a kinase domain and regulates various physical processes and diseases. However, its effects on pathogenesis of human bladder cancer (BCa) has not been clarified yet. Our microarray analysis has suggested that calcium signaling pathway is connected with bladder cancer via MAPK pathway. Therefore, we aim to investigate the mechanism of TRPM7 in BCa tumorigenesis by using BCa tissues compared with normal bladder epithelium tissues, as well as using distinct BCa cell lines (EJ, 5637 and T24). We observed increased TRPM7 expression and dysregulation of proteins involved in Epithelial-Mesenchymal Transition (EMT) in BCa tissues. Moreover, knockdown of TRPM7 in BCa cells reversed the EMT status, accompanied by increase of reactive oxygen species (ROS). Furthermore, TRPM7 deficiency could inhibit BCa cell proliferation, migration and invasion, as well as induce p-ERK1/2 and suppress PI3K/AKT at the protein level. Downregulation of TRPM7 promoted cell cycle arrest at G0/G1 phase and apoptosis in vitro, which could be recovered by pre-treatment with U0126 to deactivate ERK1/2, suggesting a close correlation between TRPM7 and the MAPK signaling pathway. Furthermore, a NOD/SCID mouse model transplanted using the BCa cells was established, revealing delayed tumor growth by reduced protein activity and mRNA transcription of TRPM7 in vivo. Our results suggested TRPM7 might be essential for BCa tumorigenesis by interfering BCa cell proliferation, motility and apoptosis. PMID:27662662

  7. Decreased TRPM7 inhibits activities and induces apoptosis of bladder cancer cells via ERK1/2 pathway.

    PubMed

    Cao, Rui; Meng, Zhe; Liu, Tongzu; Wang, Gang; Qian, Guofeng; Cao, Tingting; Guan, Xinyuan; Dan, Hancai; Xiao, Yu; Wang, Xinghuan

    2016-11-08

    Transient receptor potential melastatin 7 (TRPM7) functions as a Mg2+/Ca2+-permeable channel fused with a kinase domain and regulates various physical processes and diseases. However, its effects on pathogenesis of human bladder cancer (BCa) has not been clarified yet. Our microarray analysis has suggested that calcium signaling pathway is connected with bladder cancer via MAPK pathway. Therefore, we aim to investigate the mechanism of TRPM7 in BCa tumorigenesis by using BCa tissues compared with normal bladder epithelium tissues, as well as using distinct BCa cell lines (EJ, 5637 and T24). We observed increased TRPM7 expression and dysregulation of proteins involved in Epithelial-Mesenchymal Transition (EMT) in BCa tissues. Moreover, knockdown of TRPM7 in BCa cells reversed the EMT status, accompanied by increase of reactive oxygen species (ROS). Furthermore, TRPM7 deficiency could inhibit BCa cell proliferation, migration and invasion, as well as induce p-ERK1/2 and suppress PI3K/AKT at the protein level. Downregulation of TRPM7 promoted cell cycle arrest at G0/G1 phase and apoptosis in vitro, which could be recovered by pre-treatment with U0126 to deactivate ERK1/2, suggesting a close correlation between TRPM7 and the MAPK signaling pathway. Furthermore, a NOD/SCID mouse model transplanted using the BCa cells was established, revealing delayed tumor growth by reduced protein activity and mRNA transcription of TRPM7 in vivo. Our results suggested TRPM7 might be essential for BCa tumorigenesis by interfering BCa cell proliferation, motility and apoptosis.

  8. A Novel Tetraenoic Fatty Acid Isolated from Amaranthus spinosus Inhibits Proliferation and Induces Apoptosis of Human Liver Cancer Cells

    PubMed Central

    Mondal, Arijit; Guria, Tanmoy; Maity, Tapan Kumar; Bishayee, Anupam

    2016-01-01

    Amaranthus spinosus Linn. (Family: Amaranthaceae) has been shown to be useful in preventing and mitigating adverse pathophysiological conditions and complex diseases. However, only limited information is available on the anticancer potential of this plant. In this study, we examined the antiproliferative and pro-apoptotic effects of a novel fatty acid isolated from A. spinosus—(14E,18E,22E,26E)-methyl nonacosa-14,18,22,26 tetraenoate—against HepG2 human liver cancer cells. We used 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay to determine cell viability, flow cytometry assay for cell cycle analysis, and Western blot analysis to measure protein expression of Cdc2), cyclin B1, Bcl-2-associated X protein (Bax), and B-cell lymphoma 2 (Bcl-2). The MTT assay showed that the fatty acid markedly inhibited the proliferation of HepG2 cells in a dosage-dependent fashion, with a half maximal inhibitory concentration (IC50) value of 25.52 µmol/L. This antiproliferative result was superior to that of another known fatty acid, linoleic acid (IC50 38.65 µmol/L), but comparable to that of standard anticancer drug doxorubicin (IC50 24.68 µmol/L). The novel fatty acid also induced apoptosis mediated by downregulation of cyclin B1, upregulation of Bax, and downregulation of Bcl-2, resulting in the G2/M transition arrest. Our results provide the first experimental evidence that a novel fatty acid isolated from A. spinosus exhibits significant antiproliferative activity mediated through the induction of apoptosis in HepG2 cells. These encouraging results may facilitate the development of A. spinosus fatty acid for the prevention and intervention of hepatocellular carcinoma. PMID:27669220

  9. Schisandrin B inhibits cell growth and induces cellular apoptosis and autophagy in mouse hepatocytes and macrophages: implications for its hepatotoxicity

    PubMed Central

    Zhang, Yi; Zhou, Zhi-Wei; Jin, Hua; Hu, Chengbin; He, Zhi-Xu; Yu, Zhi-Ling; Ko, Kam-Ming; Yang, Tianxin; Zhang, Xueji; Pan, Si-Yuan; Zhou, Shu-Feng

    2015-01-01

    A number of drugs and herbal compounds have been documented to cause hepatoxicity. Schisandrin B (Sch B) is an active dibenzocyclooctadiene isolated from Schisandrae fructus, with a wide array of pharmacological activities. However, the potential hepatotoxicity of Sch B is a major safety concern, and the underlying mechanism for Sch B-induced liver toxic effects is not fully elucidated. In the present study, we aimed to investigate the liver toxic effects and the molecular mechanisms of Sch B in mouse liver and macrophage cells. The results have shown that Sch B exhibits potent grow inhibitory, proapoptotic, and proautophagic effects in AML-12 and RAW 264.7 cells. Sch B markedly arrested cells in G1 phase in both cell lines, accompanied by the down-regulation of cyclin dependent kinase 2 (CDK2) and cyclin D1 and up-regulation of p27 Kip1 and checkpoint kinase 1. Furthermore, Sch B markedly increased the apoptosis of AML-12 and RAW 264.7 cells with a decrease in the expression of B-cell lymphoma-extra-large and (Bcl-xl) B-cell lymphoma 2 (Bcl-2), but an increase in the expression of B-cell lymphoma 2-associated X protein (Bax). Sch B promoted the cleavage of caspase 3 and poly-adenosine diphosphate-ribose polymerase (PARP) in both cell lines. Additionally, Sch B significantly induced autophagy of AML-12 and RAW 264.7 cells. Sch B inhibited the activation of phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) signaling pathway, as indicated by their altered phosphorylation, contributing to the proautophagic effect of Sch B. Taken together, our findings show that the inducing effects of Sch B on cell cycle arrest, apoptosis, and autophagy may contribute to its liver toxic effects, which might provide a clue for the investigation of the molecular toxic targets and underlying mechanisms for Sch B-induced hepatotoxicity in herbal consumers. More studies are warranted to fully delineate the underlying mechanisms, efficacy, and

  10. Inhibition of retinal detachment-induced apoptosis in photoreceptors by a small peptide inhibitor of the fas receptor.

    PubMed

    Besirli, Cagri G; Chinskey, Nicholas D; Zheng, Qiong-Duan; Zacks, David N

    2010-04-01

    Purpose. To test the effect of a small peptide inhibitor (Met12) of the Fas receptor on the activation of extrinsic and intrinsic apoptosis pathways after retinal detachment. Methods. Retinal-RPE separation was created in Brown Norway rats by subretinal injection of 1% hyaluronic acid. Met12, derived from the Fas-binding extracellular domain of the oncoprotein Met, was injected into the subretinal space at the time of separation. A mutant peptide and vehicle administered in a similar fashion acted as inactive controls. The extrinsic apoptotic pathway was induced in 661W cells using a Fas-activating antibody in the presence or absence of Met12. Caspase 3, caspase 8, and caspase 9 activities were measured with calorimetric and luminescent assays in retinal extracts and cell lysates. Terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) was performed in retinal sections 3 days after separation. Histology was performed in retinal sections 2 months after retinal detachment. Results. Met12 inhibited Fas-induced caspase 8 activation in 661W cells. Similarly, administration of Met12 into the subretinal space inhibited the activation of caspase 3, caspase 8, and caspase 9 after retinal detachment. This corresponded to a decreased level of TUNEL-positive staining of photoreceptors after retinal-RPE separation in animals that received Met12, but not inactive mutant, peptide treatment. After 2 months, the outer nuclear layer was significantly thicker, and the photoreceptor count was higher in animals treated with subretinal Met12. Conclusions. The small peptide Met12 may serve as a photoreceptor-protective agent in the setting of retinal-RPE separation.

  11. PEDF attenuates hypoxia-induced apoptosis and necrosis in H9c2 cells by inhibiting p53 mitochondrial translocation via PEDF-R.

    PubMed

    Wang, Xiaoyu; Zhang, Yiqian; Lu, Peng; Zhang, Hao; Li, Yufeng; Dong, Hongyan; Zhang, Zhongming

    2015-09-25

    Pigment epithelial-derived factor (PEDF) is a multifunctional secreted glycoprotein, which could protect against hypoxia-induced cell death related to its anti-oxidative effect in cultured cardiomyocytes. However, the pathway mediating this cytoprotective process has not been fully established. Here we confirmed that PEDF bound to pigment epithelial-derived factor receptor (PEDF-R) expressed on the membrane of H9c2 cells. Under hypoxic condition, PEDF increased the ratio of MDM2:p53, so as to inhibited p53 mitochondrial translocation via PEDF-R. As a result, mitochondrial outer membrane permeabilization (MOMP) and mitochondrial permeability transition pore (MPTP) opening were inhibited, meanwhile cleaved caspase-3, PARP and the release of HMGB1 were reduced. Accordingly, apoptosis and necrosis were attenuated simultaneously. We conclude that PEDF-R mediates PEDF attenuates hypoxia-induced apoptosis and necrosis in H9c2 cells by inhibiting p53 mitochondrial translocation.

  12. Allicin inhibits oxidative stress-induced mitochondrial dysfunction and apoptosis by promoting PI3K/AKT and CREB/ERK signaling in osteoblast cells

    PubMed Central

    DING, GUOLIANG; ZHAO, JIANQUAN; JIANG, DIANMING

    2016-01-01

    Osteoporosis is a disease of the skeleton that is characterized by the loss of bone mass and degeneration of bone microstructure, resulting in an increased risk of fracture. Oxidative stress, which is known to promote oxidative damage to mitochondrial function and also cell apoptosis, has been recently indicated to be implicated in osteoporosis. However, there are few agents that counteract oxidative stress in osteoporosis. In the present study, the protective effects of allicin against the oxidative stress-induced mitochondrial dysfunction and apoptosis were investigated in murine osteoblast-like MC3T3-E1 cells. The results demonstrated that allicin counteracted the reduction of cell viability and induction of apoptosis caused by hydrogen peroxide (H2O2) exposure. The inhibition of apoptosis by allicin was confirmed by the inhibition of H2O2-induced cytochrome c release and caspase-3 activation. Moreover, the inhibition of apoptosis by allicin was identified to be associated with the counteraction of H2O2-induced mitochondrial dysfunction. In addition, allicin was demonstrated to be able to significantly ameliorate the repressed phosphoinositide 3-kinase (PI3K)/AKT and cyclic adenosine monophosphate response element-binding protein (CREB)/extracellular-signal-regulated kinase (ERK) signaling pathways by H2O2, which may also be associated with the anti-oxidative stress effects of allicin. In conclusion, allicin protects osteoblasts from H2O2-induced oxidative stress and apoptosis in MC3T3-E1 cells by improving mitochondrial function and the activation of PI3K/AKT and CREB/ERK signaling. The present study implies a promising role of allicin in oxidative stress-associated osteoporosis. PMID:27284348

  13. 3-Bromopyruvate and sodium citrate target glycolysis, suppress survivin, and induce mitochondrial-mediated apoptosis in gastric cancer cells and inhibit gastric orthotopic transplantation tumor growth

    PubMed Central

    WANG, TING-AN; ZHANG, XIAO-DONG; GUO, XING-YU; XIAN, SHU-LIN; LU, YUN-FEI

    2016-01-01

    Glycolysis is the primary method utilized by cancer cells to produce the energy (adenosine triphosphate, ATP) required for cell proliferation. Therefore, inhibition of glycolysis may inhibit tumor growth. We previously found that both 3-bromopyruvate (3-BrPA) and sodium citrate (SCT) can inhibit glycolysis in vitro; however, the underlying inhibitory mechanisms remain unclear. In the present study, we used a human gastric cancer cell line (SGC-7901) and an orthotopic transplantation tumor model in nude mice to explore the specific mechanisms of 3-BrPA and SCT. We found that both 3-BrPA and SCT effectively suppressed cancer cell proliferation, arrested the cell cycle, induced apoptosis, and decreased the production of lactate and ATP. 3-BrPA significantly reduced the glycolytic enzyme hexokinase activity, while SCT selectively inhibited phosphofructokinase-1 activity. Furthermore, 3-BrPA and SCT upregulated the expression of pro-apoptotic proteins (Bax, cytochrome c, and cleaved caspase-3) and downregulated the expression of anti-apoptotic proteins (Bcl-2 and survivin). Finally, our animal model of gastric cancer indicated that intraperitoneal injection of 3-BrPA and SCT suppressed orthotopic transplantation tumor growth and induced tumor apoptosis. Taken together, these results suggest that 3-BrPA and SCT selectively suppress glycolytic enzymes, decrease ATP production, induce mitochondrial-mediated apoptosis, downregulate survivin, and inhibit tumor growth. Moreover, an intraperitoneal injection is an effective form of administration of 3-BrPA and SCT. PMID:26708213

  14. 3-bromopyruvate and sodium citrate target glycolysis, suppress survivin, and induce mitochondrial-mediated apoptosis in gastric cancer cells and inhibit gastric orthotopic transplantation tumor growth.

    PubMed

    Wang, Ting-An; Zhang, Xiao-Dong; Guo, Xing-Yu; Xian, Shu-Lin; Lu, Yun-Fei

    2016-03-01

    Glycolysis is the primary method utilized by cancer cells to produce the energy (adenosine triphosphate, ATP) required for cell proliferation. Therefore, inhibition of glycolysis may inhibit tumor growth. We previously found that both 3-bromopyruvate (3-BrPA) and sodium citrate (SCT) can inhibit glycolysis in vitro; however, the underlying inhibitory mechanisms remain unclear. In the present study, we used a human gastric cancer cell line (SGC-7901) and an orthotopic transplantation tumor model in nude mice to explore the specific mechanisms of 3-BrPA and SCT. We found that both 3-BrPA and SCT effectively suppressed cancer cell proliferation, arrested the cell cycle, induced apoptosis, and decreased the production of lactate and ATP. 3-BrPA significantly reduced the glycolytic enzyme hexokinase activity, while SCT selectively inhibited phosphofructokinase-1 activity. Furthermore, 3-BrPA and SCT upregulated the expression of pro-apoptotic proteins (Bax, cytochrome c, and cleaved caspase-3) and downregulated the expression of anti-apoptotic proteins (Bcl-2 and survivin). Finally, our animal model of gastric cancer indicated that intraperitoneal injection of 3-BrPA and SCT suppressed orthotopic transplantation tumor growth and induced tumor apoptosis. Taken together, these results suggest that 3-BrPA and SCT selectively suppress glycolytic enzymes, decrease ATP production, induce mitochondrial-mediated apoptosis, downregulate survivin, and inhibit tumor growth. Moreover, an intraperitoneal injection is an effective form of administration of 3-BrPA and SCT.

  15. Inhibition of c-kit tyrosine kinase by imatinib mesylate induces apoptosis in mast cells in rheumatoid synovia: a potential approach to the treatment of arthritis

    PubMed Central

    Juurikivi, A; Sandler, C; Lindstedt, K; Kovanen, P; Juutilainen, T; Leskinen, M; Maki, T; Eklund, K

    2005-01-01

    Background: Mast cells have been implicated in the pathogenesis of arthritis, but elucidation of their precise role has been hampered by a lack of efficient and selective inhibitors of their function. Objective: To elucidate the role of mast cells in the pathogenesis of rheumatoid arthritis (RA) and to assess whether apoptosis of cultured and synovial tissue mast cells can be induced by inhibiting mast cell growth factor receptor, c-kit tyrosine kinase. Methods and results: Double staining with tumour necrosis factor (TNF) α and tryptase antibodies showed the presence of TNFα positive mast cells in human rheumatoid synovial tissue. Selective activation of mast cells by anti-IgE resulted in production of TNFα in synovial tissue cultures. Inhibition of the c-kit tyrosine kinase with imatinib mesylate (1.0–10 µmol/l) induced profound apoptosis in cultured mast cells as judged by typical apoptotic morphology, increased number of apoptotic nucleosomes, and activation of caspases 8 and 9. Importantly, imatinib also induced apoptosis of mast cells in explant cultures of synovial tissue obtained from patients with RA as judged by a TUNEL assay. Inhibition of c-kit tyrosine kinase was accompanied by significant reduction of TNFα production in synovial tissue cultures. Conclusion: Mast cells may have a role in the pathogenesis of RA, and inhibition of c-kit may be a new means of inhibiting mast cell activity and of abrogating the contribution of mast cells to synovial inflammation in RA. PMID:16014680

  16. Andrographolide Analogue Induces Apoptosis and Autophagy Mediated Cell Death in U937 Cells by Inhibition of PI3K/Akt/mTOR Pathway

    PubMed Central

    Kumar, Deepak; Das, Bimolendu; Sen, Rupashree; Kundu, Priyanka; Manna, Alak; Sarkar, Avijit; Chowdhury, Chinmay; Chatterjee, Mitali; Das, Padma

    2015-01-01

    Background Current chemotherapeutic agents based on apoptosis induction are lacking in desired efficacy. Therefore, there is continuous effort to bring about new dimension in control and gradual eradication of cancer by means of ever evolving therapeutic strategies. Various forms of PCD are being increasingly implicated in anti-cancer therapy and the complex interplay among them is vital for the ultimate fate of proliferating cells. We elaborated and illustrated the underlying mechanism of the most potent Andrographolide analogue (AG–4) mediated action that involved the induction of dual modes of cell death—apoptosis and autophagy in human leukemic U937 cells. Principal Findings AG–4 induced cytotoxicity was associated with redox imbalance and apoptosis which involved mitochondrial depolarisation, altered apoptotic protein expressions, activation of the caspase cascade leading to cell cycle arrest. Incubation with caspase inhibitor Z-VAD-fmk or Bax siRNA decreased cytotoxic efficacy of AG–4 emphasising critical roles of caspase and Bax. In addition, AG–4 induced autophagy as evident from LC3-II accumulation, increased Atg protein expressions and autophagosome formation. Pre-treatment with 3-MA or Atg 5 siRNA suppressed the cytotoxic effect of AG–4 implying the pro-death role of autophagy. Furthermore, incubation with Z-VAD-fmk or Bax siRNA subdued AG–4 induced autophagy and pre-treatment with 3-MA or Atg 5 siRNA curbed AG–4 induced apoptosis—implying that apoptosis and autophagy acted as partners in the context of AG–4 mediated action. AG–4 also inhibited PI3K/Akt/mTOR pathway. Inhibition of mTOR or Akt augmented AG–4 induced apoptosis and autophagy signifying its crucial role in its mechanism of action. Conclusions Thus, these findings prove the dual ability of AG–4 to induce apoptosis and autophagy which provide a new perspective to it as a potential molecule targeting PCD for future cancer therapeutics. PMID:26436418

  17. NG as a novel nitric oxide donor induces apoptosis by increasing reactive oxygen species and inhibiting mitochondrial function in MGC803 cells.

    PubMed

    Liu, Ling; Li, Tingting; Tan, Jiani; Fu, Junjie; Guo, Qianqian; Ji, Hui; Zhang, Yihua

    2014-11-01

    NG, O(2)-(2,4-dinitro-5-{[2-(12-en-28-β-D-galactopyranosyl-oleanolate-3-yl)-oxy-2-oxoethyl] amino} phenyl) 1-(N-hydroxyethylmethylamino) diazen-1-ium-1,2-diolate, was identified in our laboratory as a novel nitric oxide-releasing prodrug with antitumor effects. A previous study showed that NG inhibited cell growth, and induced apoptosis in HepG2 cells. In this study, the inhibitory effects of NG on the viability of MGC803 cells were examined using methylthiazolyl tetrazolium biomide (MTT) assay, neutral red assay and trypan blue exclusion test. The results showed that NG had strong cytotoxicity to induce apoptosis, which was characterized by a significant externalization of phosphatidylserine, nuclear morphological changes and enhanced Bax-to-Bcl-2 ratio. Moreover, the release of cytochrome c (Cyt c) from mitochondria and the activation of caspase-9/3 were also detected, indicating that NG may induce apoptosis through a mitochondrial-mediated pathway. NG induced mitochondrial dysfunction in MGC803 cells by altering membrane potential (△Ψm), the inhibition of complexes I, II and IV consequently decreasing ATP level. Furthermore, the treatment of MGC803 cells with NG caused a marked rise in oxidative stress as characterized by accumulation of reactive oxygen species (ROS), excessive malondialdehyde (MDA) production and a reduction in glutathione hormone (GSH) level and superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activity. In addition, pretreatment with N-acetylcysteine (NAC), a GSH synthesis precursor, was partially protective against the NG-induced ROS generation and cell apoptosis. In contrast, pretreatment of MGC803 cells with L-buthionine-S, R-sulfoximine (BSO), a GSH synthesis inhibitor, increased the ROS levels, and aggravated cell apoptosis by NG. These results suggest that NG-induced apoptosis in MGC803 cells is mediated, at least in part, by the increase in ROS production, oxidative stress and mitochondrial dysfunction.

  18. Local anesthetics induce human renal cell apoptosis.

    PubMed

    Lee, H Thomas; Xu, Hua; Siegel, Cory D; Krichevsky, Igor E

    2003-01-01

    Renal cell apoptosis contributes significantly to the pathogenesis of acute renal failure. Local anesthetics induce apoptosis in neuronal and lymphocytic cell lines. We examined the effects of chronic (48 h) local anesthetic treatment (lidocaine, bupivacaine and tetracaine) on human proximal tubular (HK-2) cells. Apoptosis induction was assessed by detecting poly(ADP)-ribose polymerase fragmentation, caspase activation, terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling (TUNEL) staining, DNA laddering and by cellular morphology. Cell death was quantified by measuring neutral red dye uptake and lactate dehydrogenase released into the cell culture medium. All 3 local anesthetics caused concentration-dependent cell death, induced HK-2 cell apoptosis and potentiated TNF-alpha induced apoptosis. Local anesthetics induced HK-2 cell apoptosis by activation of caspases 3, 6, 7, 8 and 9. ZVAD-fmk, a pan-caspase inhibitor, blocked the local anesthetic induced HK-2 cell apoptosis. Local anesthetics also inhibited the activities of anti-apoptotic kinases protein kinase B (Akt) and extracellular signal regulated mitrogen-activated protein kinase. Local anesthetic's pro-apoptotic effects are independent of sodium channel inhibition as tetrodotoxin, a selective voltage-gated sodium channel blocker, failed to mimic local anesthetic-mediated induction or potentiation of HK-2 cell apoptosis. We conclude that local anesthetics induce human renal cell apoptotic signaling by caspase activation and via inhibition of pro-survival signaling pathways.

  19. Cyanidin suppresses amyloid beta-induced neurotoxicity by inhibiting reactive oxygen species-mediated DNA damage and apoptosis in PC12 cells

    PubMed Central

    Wang, Yi; Fu, Xiao-ting; Li, Da-wei; Wang, Kun; Wang, Xin-zhi; Li, Yuan; Sun, Bao-liang; Yang, Xiao-yi; Zheng, Zun-cheng; Cho, Nam Chun

    2016-01-01

    Amyloid beta (Aβ)-induced oxidative stress is a major pathologic hallmark of Alzheimer's disease. Cyanidin, a natural flavonoid compound, is neuroprotective against oxidative damage-mediated degeneration. However, its molecular mechanism remains unclear. Here, we investigated the effects of cyanidin pretreatment against Aβ-induced neurotoxicity in PC12 cells, and explored the underlying mechanisms. Cyanidin pretreatment significantly attenuated Aβ-induced cell mortality and morphological changes in PC12 cells. Mechanistically, cyanidin effectively blocked apoptosis induced by Aβ, by restoring the mitochondrial membrane potential via upregulation of Bcl-2 protein expression. Moreover, cyanidin markedly protected PC12 cells from Aβ-induced DNA damage by blocking reactive oxide species and superoxide accumulation. These results provide evidence that cyanidin suppresses Aβ-induced cytotoxicity, by preventing oxidative damage mediated by reactive oxide species, which in turn inhibits mitochondrial apoptosis. Our study demonstrates the therapeutic potential of cyanidin in the prevention of oxidative stress-mediated Aβ neurotoxicity. PMID:27335564

  20. Recombinant Lipoprotein Rv1016c Derived from Mycobacterium tuberculosis Is a TLR-2 Ligand that Induces Macrophages Apoptosis and Inhibits MHC II Antigen Processing

    PubMed Central

    Su, Haibo; Zhu, Shenglin; Zhu, Lin; Huang, Wei; Wang, Honghai; Zhang, Zhi; Xu, Ying

    2016-01-01

    TLR2-dependent cellular signaling in Mycobacterium tuberculosis-infected macrophages causes apoptosis and inhibits class II major histocompatibility complex (MHC-II) molecules antigen processing, leading to evasion of surveillance. Mycobacterium tuberculosis (MTB) lipoproteins are an important class of Toll-like receptor (TLR) ligand, and identified as specific components that mediate these effects. In this study, we identified and characterized MTB lipoprotein Rv1016c (lpqT) as a cell wall associated-protein that was exposed on the cell surface and enhanced the survival of recombinants M. smegmatis_Rv1016c under stress conditions. We found that Rv1016c lipoprotein was a novel TLR2 ligand and able to induce macrophage apoptosis in a both dose- and time-dependent manner. Additionally, apoptosis induced by Rv1016c was reserved in THP-1 cells blocked with anti-TLR-2 Abs or in TLR2−/− mouse macrophages, indicating that Rv1016c-induced apoptosis is dependent on TLR2. Moreover, we demonstrated that Rv1016c lipoprotein inhibited IFN-γ-induced MHC-II expression and processing of soluble antigens in a TLR2 dependent manner. Class II transactivator (CIITA) regulates MHC II expression. In this context, Rv1016c lipoprotein diminished IFN-γ-induced expression of CIITA IV through TLR2 and MAPK Signaling. TLR2-dependent apoptosis and inhibition of MHC-II Ag processing induced by Rv1016c during mycobacteria infection may promote the release of residual bacilli from apoptotic cells and decrease recognition by CD4+ T cells. These mechanisms may allow intracellular MTB to evade immune surveillance and maintain chronic infection. PMID:27917375

  1. DIETARY ISOTHIOCYANATE IBERIN INHIBITS GROWTH AND INDUCES APOPTOSIS IN HUMAN GLIOBLASTOMA CELLS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this study, we evaluated the antiproliferative and proapoptotic effects of the isothiocyanate iberin, a bioactive agent in Brassicaceae species, in human glioblastoma cells. The human glioblastoma cell cultures were treated with different concentrations of iberin and tested for growth inhibition...

  2. beta-Catenin/TCF pathway plays a vital role in selenium induced-growth inhibition and apoptosis in esophageal squamous cell carcinoma (ESCC) cells.

    PubMed

    Zhang, Wei; Yan, Shuang; Liu, Mei; Zhang, Guo; Yang, Shangbin; He, Shun; Bai, Jinfeng; Quan, Lanping; Zhu, Hongxia; Dong, Yan; Xu, Ningzhi

    2010-10-01

    Epidemiological and experimental studies have indicated selenium could reduce the risk of some cancers. In our present study, growth inhibition and apoptosis were detected upon methylseleninic acid (MSA) treatment in human esophageal squamous cell carcinoma cell lines EC9706 and KYSE150. MSA reduced beta-catenin protein levels, while there was no significant change observed on transcriptional levels. Moreover, we found MSA accelerated the degradation of beta-catenin and activated glycogen synthase kinase 3beta (GSK-3beta). Some targets of beta-catenin/TCF pathway and apoptosis-related genes altered after MSA treatment. Notably, utilizing the inducible 293-TR/beta-catenin cell line, we found the apoptotic phenotypes induced by MSA were partially reversed by the overexpression of beta-catenin. Overall, our data indicate the effects induced by MSA in ESCC cells may act on the inhibition of beta-catenin/TCF pathway.

  3. Dl-3-n-butylphthalide improves functional recovery in rats with spinal cord injury by inhibiting endoplasmic reticulum stress-induced apoptosis

    PubMed Central

    He, Zili; Zhou, Yulong; Huang, Yan; Wang, Qingqing; Zheng, Binbin; Zhang, Hongyu; Li, Jiawei; Liu, Yanlong; Wu, Fenzan; Zhang, Xie; Tong, Songlin; Wang, Maofeng; Wang, Zhouguang; He, Huacheng; Xu, Huazi; Xiao, Jian

    2017-01-01

    Endoplasmic reticulum (ER) stress-induced apoptosis occurs in the spinal cord following traumatic spinal cord injury (SCI). Dl-3-n-butylphthalide (NBP) exerts an neuroprotective effects against both ischemic brain injury and neurodegenerative diseases; however, the relationship between ER stress-induced apoptosis and the therapeutic effect of NBP in SCI remains unclear. In this study, moderate spinal cord injuries were induced in Sprague-Dawley (SD) rats with a vascular clip. NBP was administered by oral (80 mg/kg/d) gavage 2 h before injury and then once daily for 28 d thereafter. Neurological recovery was assessed using the Basso, Beattie, and Bresnahan (BBB) locomotion rating scale, the inclined plane test, and the footprint analysis. Neuronal cell death was examined by TUNEL staining at 7 days post-injury. ER stress and apoptosis-related proteins were quantified by immunofluorescence staining and western blotting both in vivo and in vitro. Our results showed that NBP significantly decreased spinal cord lesion cavity area and improved locomotor recovery in SD rats after SCI. NBP also decreased neuronal apoptosis and inhibited activation of the caspase 3 cascade. Upregulation of ER stress-related proteins, such as GRP78, ATF-6, ATF-4, PDI, XBP-1, and CHOP, was reversed by NBP treatment in SD rats with SCI. Similarly, NBP effectively ameliorated ER stress and apoptosis-related protein expression induced by incubation with thapsigargin (TG) in PC12 cells. Our findings demonstrate that NBP treatment alleviates secondary SCI by inhibiting ER stress-induced apoptosis, thereby promoting neurological and locomoter functional recovery. PMID:28386335

  4. Silencing of AP-4 inhibits proliferation, induces cell cycle arrest and promotes apoptosis in human lung cancer cells.

    PubMed

    Hu, Xuanyu; Guo, Wei; Chen, Shanshan; Xu, Yizhuo; Li, Ping; Wang, Huaqi; Chu, Heying; Li, Juan; DU, Yuwen; Chen, Xiaonan; Zhang, Guojun; Zhao, Guoqiang

    2016-06-01

    Activating enhancer-binding protein (AP)-4 is a member of the basic helix-loop-helix transcription factors, and is involved in tumor biology. However, the role of AP-4 in human lung cancer remains to be fully elucidated. In the present study, the expression of AP-4 in human lung cancer tissues and cells was investigated by reverse transcription-quantitative polymerase chain reaction, and it was observed that the level of AP-4 was increased in tumor tissues and cells compared with their normal counterparts. AP-4 expression was knocked down by transfection with a specific small interfering RNA (siRNA) in lung cancer cells, and this indicated that siRNA-mediated silencing of AP-4 inhibited cell proliferation, arrested the cell cycle at the G0/G1 phase and induced apoptosis by modulating the expression of p21 and cyclin D1. The results of the present study suggest that AP-4 may be an oncoprotein that has a significant role in lung cancer, and that siRNA-mediated silencing of AP-4 may have therapeutic potential as a strategy for the treatment of lung cancer.

  5. Mechanism of Taiwan Mingjian Oolong Tea to Inhibit Isoproterenol-Induced Hypertrophy and Apoptosis in Cardiomyoblasts.

    PubMed

    Yeh, Yu-Lan; Tsai, Hsiang-I; Cheng, Shiu-Min; Pai, Peiying; Ho, Tsung-Jung; Chen, Ray-Jade; Lai, Chao-Hung; Huang, Pei-Jane; Padma, V Vijaya; Huang, Chih-Yang

    2016-01-01

    This study investigates the cardio-protective effect of Nos. 1 and 5 extracts from Taiwan Mingjian Oolong Tea on H9c2 cardiomyoblast cells treated with isoproterenol (ISO). Treatment with Nos. 1 and 5 extracts increased cell viability and blocked apoptosis in ISO exposed H9c2 cells. Moreover, Nos. 1 and 5 extracts blocked hypertrophy markers like G[Formula: see text]s, calcineurin, NFATc3, and BNP, thereby increasing cell proliferation markers -PI3K and AKT in a dose dependent manner. In contrast, apoptotic proteins, such as caspase-3 and cytochrome c were decreased in H9c2 cells treated with Nos. 1 and 5 extracts. We confirmed that the protective effect of No. 1 extract was partially mediated through the expression of ERK and p38, however, the No. 5 extract showed a protective effect via the ERK, JNK, and p38 pathways. This evidence provides new insights into the pharmacological role and therapeutic mechanism of Taiwan Mingjian Oolong Tea in heart diseases.

  6. Reactive oxygen species-dependent HSP90 protein cleavage participates in arsenical As(+3)- and MMA(+3)-induced apoptosis through inhibition of telomerase activity via JNK activation.

    PubMed

    Shen, Shing-Chuan; Yang, Liang-Yo; Lin, Hui-Yi; Wu, Chin-Yen; Su, Tsung-Hsien; Chen, Yen-Chou

    2008-06-01

    The effects of six arsenic compounds including As(+3), MMA(+3), DMA(+3), As(+5), MMA(+5), and DMA(+5) on the viability of NIH3T3 cells were examined. As(+3) and MMA(+3), but not the others, exhibited significant cytotoxic effects in NIH3T3 cells through apoptosis induction. The apoptotic events such as DNA fragmentation and chromosome condensation induced by As(+3) and MMA(+3) were prevented by the addition of NAC and CAT, and induction of HO-1 gene expression in accordance with cleavage of the HSP90 protein, and suppression of telomerase activity were observed in NIH3T3 cells under As(+3) and MMA(+3) treatments. An increase in the intracellular peroxide level was examined in As(+3)- and MMA(+3)-treated NIH3T3 cells, and As(+3)- and MMA(+3)-induced apoptotic events were blocked by NAC, CAT, and DPI addition. HSP90 inhibitors, GA and RD, significantly attenuated the telomerase activity in NIH3T3 cells with an enhancement of As(+3)- and MMA(+3)-induced cytotoxicity. Suppression of JNKs significantly inhibited As(+3)- and MMA(+3)-induced apoptosis by blocking HSP90 protein cleavage and telomerase reduction in NIH3T3 cells. Furthermore, Hb, SnPP, and dexferosamine showed no effect against As(+3)- and MMA(+3)-induced apoptosis, and overexpression of HO-1 protein or inhibition of HO-1 protein expression did not affect the apoptosis induced by As(+3) or MMA(+3). These data provide the first evidence to indicate that apoptosis induced by As(+3) and MMA(+3) is mediated by an ROS-dependent degradation of HSP90 protein and reduction of telomerase via JNK activation, and HO-1 induction might not be involved.

  7. Inhibition of VDAC1 prevents Ca²⁺-mediated oxidative stress and apoptosis induced by 5-aminolevulinic acid mediated sonodynamic therapy in THP-1 macrophages.

    PubMed

    Chen, Haibo; Gao, Weiwei; Yang, Yang; Guo, Shuyuan; Wang, Huan; Wang, Wei; Zhang, Shuisheng; Zhou, Qi; Xu, Haobo; Yao, Jianting; Tian, Zhen; Li, Bicheng; Cao, Wenwu; Zhang, Zhiguo; Tian, Ye

    2014-12-01

    Ultrasound combined with endogenous protoporphyrin IX derived from 5-aminolevulinic acid (ALA-SDT) is known to induce apoptosis in multiple cancer cells and macrophages. Persistent retention of macrophages in the plaque has been implicated in the pathophysiology and progression of atherosclerosis. Here we investigated the effects of inhibition of voltage-dependent anion channel 1 (VDAC1) on ALA-SDT-induced THP-1 macrophages apoptosis. Cells were pre-treated with VDAC1 inhibitor 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS) disodium salt for 1 h or downregulated VDAC1 expression by small interfering RNA and exposed to ultrasound. Cell viability was assessed by MTT assay, and cell apoptosis along with necrosis was evaluated by Hoechst 33342/propidium iodide staining and flow cytometry. Levels of cytochrome c release was assessed by confocal microscope and Western blot. The levels of full length caspases, caspase activation, and VDAC isoforms were analyzed by Western blot. Intracellular reactive oxygen species generation, mitochondrial membrane permeability, and intracellular Ca(2+) [Ca(2+)]i levels were measured with fluorescent probes. We confirmed that the pharmacological inhibition of VDAC1 by DIDS notably prevented ALA-SDT-induced cell apoptosis in THP-1 macrophages. Additionally, DIDS significantly inhibited intracellular ROS generation and apoptotic biochemical changes such as inner mitochondrial membrane permeabilization, loss of mitochondrial membrane potential, cytochrome c release and activation of caspase-3 and caspase-9. Moreover, ALA-SDT elevated the [Ca(2+)]i levels and it was also notably reduced by DIDS. Furthermore, both of intracellular ROS generation and cell apoptosis were predominately inhibited by Ca(2+) chelating reagent BAPTA-AM. Intriguingly, ALA-treatment markedly augmented VDAC1 protein levels exclusively, and the downregulation of VDAC1 expression by specific siRNA also significantly abolished cell apoptosis. Altogether, these

  8. The metabolites of glutamine prevent hydroxyl radical-induced apoptosis through inhibiting mitochondria and calcium ion involved pathways in fish erythrocytes.

    PubMed

    Li, Huatao; Jiang, Weidan; Liu, Yang; Jiang, Jun; Zhang, Yongan; Wu, Pei; Zhao, Juan; Duan, Xudong; Zhou, Xiaoqiu; Feng, Lin

    2016-03-01

    The present study explored the apoptosis pathways in hydroxyl radicals ((∙)OH)-induced carp erythrocytes. Carp erythrocytes were treated with the caspase inhibitors in physiological carp saline (PCS) or Ca(2+)-free PCS in the presence of 40μM FeSO4/20μM H2O2. The results showed that the generation of reactive oxygen species (ROS), the release of cytochrome c and DNA fragmentation were caspase-dependent, and Ca(2+) was involved in calpain activation and phosphatidylserine (PS) exposure in (∙)OH-induced carp erythrocytes. Moreover, the results suggested that caspases were involved in PS exposure, and Ca(2+) was involved in DNA fragmentation in (∙)OH-induced fish erythrocytes. These results demonstrated that there might be two apoptosis pathways in fish erythrocytes, one is the caspase and cytochrome c-dependent apoptosis that is similar to that in mammal nucleated cells, the other is the Ca(2+)-involved apoptosis that was similar to that in mammal non-nucleated erythrocytes. So, fish erythrocytes may be used as a model for studying oxidative stress and apoptosis in mammal cells. Furthermore, the present study investigated the effects of glutamine (Gln)'s metabolites [alanine (Ala), citrulline (Cit), proline (Pro) and their combination (Ala10Pro4Cit1)] on the pathways of apoptosis in fish erythrocytes. The results displayed that Ala, Cit, Pro and Ala10Pro4Cit1 effectively suppressed ROS generation, cytochrome c release, activation of caspase-3, caspase-8 and caspase-9 at the physiological concentrations, prevented Ca(2+) influx, calpain activation, PS exposure, DNA fragmentation and the degradation of the cytoskeleton and oxidation of membrane and hemoglobin (Hb) and increased activity of anti-hydroxyl radical (AHR) in (∙)OH-induced carp erythrocytes. Ala10Pro4Cit1 produced a synergistic effect of inhibited oxidative stress and apoptosis in fish erythrocytes. These results demonstrated that Ala, Cit, Pro and their combination can protect mammal erythrocytes

  9. Competitive inhibition of survivin using a cell-permeable recombinant protein induces cancer-specific apoptosis in colon cancer model.

    PubMed

    Roy, Kislay; Kanwar, Rupinder K; Krishnakumar, Subramanian; Cheung, Chun Hei Antonio; Kanwar, Jagat R

    2015-01-01

    Endogenous survivin expression has been related with cancer survival, drug resistance, and metastasis. Therapies targeting survivin have been shown to significantly inhibit tumor growth and recurrence. We found out that a cell-permeable dominant negative survivin (SurR9-C84A, referred to as SR9) competitively inhibited endogenous survivin and blocked the cell cycle at the G1/S phase. Nanoencapsulation in mucoadhesive chitosan nanoparticles (CHNP) substantially increased the bioavailability and serum stability of SR9. The mechanism of nanoparticle uptake was studied extensively in vitro and in ex vivo models. Our results confirmed that CHNP-SR9 protected primary cells from autophagy and successfully induced tumor-specific apoptosis via both extrinsic and intrinsic apoptotic pathways. CHNP-SR9 significantly reduced the tumor spheroid size (three-dimensional model) by nearly 7-fold. Effects of SR9 and CHNP-SR9 were studied on 35 key molecules involved in the apoptotic pathway. Highly significant (4.26-fold, P≤0.005) reduction in tumor volume was observed using an in vivo mouse xenograft colon cancer model. It was also observed that net apoptotic (6.25-fold, P≤0.005) and necrotic indexes (3.5-fold, P≤0.05) were comparatively higher in CHNP-SR9 when compared to void CHNP and CHNP-SR9 internalized more in cancer stem cells (4.5-fold, P≤0.005). We concluded that nanoformulation of SR9 did not reduce its therapeutic potential; however, nanoformulation provided SR9 with enhanced stability and better bioavailability. Our study presents a highly tumor-specific protein-based cancer therapy that has several advantages over the normally used chemotherapeutics.

  10. Competitive inhibition of survivin using a cell-permeable recombinant protein induces cancer-specific apoptosis in colon cancer model

    PubMed Central

    Roy, Kislay; Kanwar, Rupinder K; Krishnakumar, Subramanian; Cheung, Chun Hei Antonio; Kanwar, Jagat R

    2015-01-01

    Endogenous survivin expression has been related with cancer survival, drug resistance, and metastasis. Therapies targeting survivin have been shown to significantly inhibit tumor growth and recurrence. We found out that a cell-permeable dominant negative survivin (SurR9-C84A, referred to as SR9) competitively inhibited endogenous survivin and blocked the cell cycle at the G1/S phase. Nanoencapsulation in mucoadhesive chitosan nanoparticles (CHNP) substantially increased the bioavailability and serum stability of SR9. The mechanism of nanoparticle uptake was studied extensively in vitro and in ex vivo models. Our results confirmed that CHNP–SR9 protected primary cells from autophagy and successfully induced tumor-specific apoptosis via both extrinsic and intrinsic apoptotic pathways. CHNP–SR9 significantly reduced the tumor spheroid size (three-dimensional model) by nearly 7-fold. Effects of SR9 and CHNP–SR9 were studied on 35 key molecules involved in the apoptotic pathway. Highly significant (4.26-fold, P≤0.005) reduction in tumor volume was observed using an in vivo mouse xenograft colon cancer model. It was also observed that net apoptotic (6.25-fold, P≤0.005) and necrotic indexes (3.5-fold, P≤0.05) were comparatively higher in CHNP–SR9 when compared to void CHNP and CHNP–SR9 internalized more in cancer stem cells (4.5-fold, P≤0.005). We concluded that nanoformulation of SR9 did not reduce its therapeutic potential; however, nanoformulation provided SR9 with enhanced stability and better bioavailability. Our study presents a highly tumor-specific protein-based cancer therapy that has several advantages over the normally used chemotherapeutics. PMID:25678789

  11. Crude Garlic Extract Inhibits Cell Proliferation and Induces Cell Cycle Arrest and Apoptosis of Cancer Cells In Vitro.

    PubMed

    Bagul, Mukta; Kakumanu, Srikanth; Wilson, Thomas A

    2015-07-01

    Garlic and its lipid-based extracts have played an important medicinal role in humans for centuries that includes antimicrobial, hypoglycemic, and lipid-lowering properties. The present study was to investigate the effects of crude garlic extract (CGE) on the proliferation of human breast, prostate, hepatic, and colon cancer cell lines and mouse macrophageal cells, not previously studied. The human cancer cell lines, such as hepatic (Hep-G2), colon (Caco-2), prostate (PC-3), and breast (MCF-7), were propagated at 37°C; air/CO2 (95:5 v/v) using the ATCC-formulated RPMI-1640 Medium and 10% fetal bovine serum (FBS), while the mouse macrophage cell line (TIB-71) was propagated at 37°C; air/CO2 (95:5 v/v) using the ATCC-formulated DMEM and 10% FBS. All cells were plated at a density of ∼5000 cells/well. After overnight incubation, the cells were treated with 0.125, 0.25, 0.5, or 1 μg/mL of CGE an additional 72 h. Inhibition of cell proliferation of 80-90% was observed for Hep-G2, MCF-7, TIB-71, and PC-3 cells, but only 40-55% for the Caco-2 cells when treated with 0.25, 0.5, or 1 μg/mL. In a coculture study of Caco-2 and TIB-71 cells, inhibition of cell proliferation of 90% was observed for Caco-2 cells compared to the 40-55% when cultured separately. CGE also induced cell cycle arrest and had a fourfold increase in caspase activity (apoptosis) in PC-3 cells when treated at a dose of 0.5 or 1 μg/mL. This investigation of CGE clearly highlights the fact that the lipid bioactive compounds in CGE have the potential as promising anticancer agents.

  12. Compound K, a metabolite of ginseng saponin, inhibits colorectal cancer cell growth and induces apoptosis through inhibition of histone deacetylase activity.

    PubMed

    Kang, Kyoung Ah; Piao, Mei Jing; Kim, Ki Cheon; Zheng, Jian; Yao, Cheng Wen; Cha, Ji Won; Kim, Hye Sun; Kim, Dong Hyun; Bae, Suk Chul; Hyun, Jin Won

    2013-12-01

    In this study, we investigated the molecular mechanisms underlying the anti-proliferative effects of Compound K, with specific reference to histone modification. Exposure of HT-29 human colon cancer cells to Compound K resulted in time-dependent inhibition of histone deacetylase (HDAC) activity, mRNA and protein expression. Compound K treatment induced unmethylation of the RUNX3 promoter region such as TSA treatment and an accumulation of acetylated histones H3 and H4 within the total cellular chromatin, resulting in an enhanced ability of these histones to bind to the promoter sequences of the tumor suppressor gene Runt-related transcription factor 3 (RUNX3). Treatment of cells with Compound K increased the mRNA and protein expression of RUNX3, as well as p21, a downstream target of RUNX3. These alterations were consistent with cell cycle arrest at the G0/G1 phases and induction of apoptosis. Our results provide new insights into the mechanisms of Compound K action in human colorectal cancer cells and suggest that HDAC inhibition presents a novel approach to prevent or treat colorectal cancer.

  13. Inhibition of phospholipaseD2 increases hypoxia-induced human colon cancer cell apoptosis through inactivating of the PI3K/AKT signaling pathway.

    PubMed

    Liu, Maoxi; Fu, Zhongxue; Wu, Xingye; Du, Kunli; Zhang, Shouru; Zeng, Li

    2016-05-01

    Hypoxia is a common feature of solid tumor, and is a direct stress that triggers apoptosis in many human cell types. As one of solid cancer, hypoxia exists in the whole course of colon cancer occurrence and progression. Our previous studies shown that hypoxia induce high expression of phospholipase D2 (PLD2) and survivin in colon cancer cells. However, the correlation between PLD2 and survivin in hypoxic colon cancer cells remains unknown. In this study, we observed significantly elevated PLD2 and survivin expression levels in colon cancer tissues and cells. This is a positive correlation between of them, and co-expression of PLD2 and survivin has a positive correlation with the clinicpatholic features including tumor size, TNM stage, and lymph node metastasis. We also found that hypoxia induced the activity of PLD increased significant mainly caused by PLD2 in colon cancer cells. However, inhibition the activity of PLD2 induced by hypoxia promotes the apoptosis of human colon cancer cells, as well as decreased the expression of apoptosis markers including survivin and bcl2. Moreover, the pharmacological inhibition of PI3K/AKT supported the hypothesis that promotes the apoptosis of hypoxic colon cancer cells by PLD2 activity inhibition may through inactivation of the PI3K/AKT signaling pathway. Furthermore, interference the PLD2 gene expression leaded to the apoptosis of hypoxic colon cancer cells increased and also decreased the expression level of survivin and bcl2 may through inactivation of PI3K/AKT signaling pathway. These results indicated that PLD2 play antiapoptotic role in colon cancer under hypoxic conditions, inhibition of the activity, or interference of PLD2 gene expression will benefit for the treatment of colon cancer patients.

  14. Myofibrillogenesis regulator-1 attenuated hypoxia/reoxygenation-induced apoptosis by inhibiting the PERK/Nrf2 pathway in neonatal rat cardiomyocytes.

    PubMed

    Tao, Tian-Qi; Wang, Xiao-Reng; Liu, Mi; Xu, Fei-Fei; Liu, Xiu-Hua

    2015-03-01

    The purpose of this study was to investigate the role of myofibrillogenesis regulator-1 (MR-1) in cardiomyocyte apoptosis induced by hypoxia/reoxygenation (H/R), through protein kinase R-like ER kinase (PERK)/nuclear factor erythroid 2-related factor 2 (Nrf2) pathway. To address this aim, an H/R model of neonatal rat cardiomyocytes was used. MR-1 was overexpressed using an adenoviral vector system and knocked down using MR-1 specific siRNA. Apoptosis was assessed by using Annexin V/PI double staining, terminal deoxynucleotidyl transferase mediated dUTP-biotin nick end labeling assay, and the Bcl-2/Bax ratio. Western blotting was used to detect the protein levels of MR-1, glucose-regulated protein 78 (GRP78), total and phosphorylated PERK, Nrf2, activating transcription factor 4 (ATF4), C/EBP homologous protein (CHOP), Bcl-2 and Bax. Immunofluorescence staining was used to assess the subcellular location of Nrf2. We found that H/R induced significant apoptosis in neonatal rat cardiomyocytes. MR-1 overexpression attenuated H/R-induced apoptosis, decreased GRP78 (P < 0.01) and CHOP expression (P < 0.05), and increased the Bcl-2/Bax ratio (P < 0.01). MR-1 overexpression suppressed H/R-induced PERK phosphorylation, Nrf2 nuclear translocation, and ATF4 expression (P < 0.01). While MR-1 knockdown aggravated H/R-induced apoptosis, increased expression of GRP78 and CHOP (P < 0.05), and decreased the Bcl-2/Bax ratio (P < 0.01). MR-1 knockdown significantly increased H/R-induced PERK phosphorylation (P < 0.05), Nrf2 nuclear translocation, and ATF4 expression (P < 0.01). These findings suggest that MR-1 alleviates H/R-induced cardiomyocyte apoptosis through inhibition of the PERK/Nrf2 pathway.

  15. NaHS Protects Cochlear Hair Cells from Gentamicin-Induced Ototoxicity by Inhibiting the Mitochondrial Apoptosis Pathway

    PubMed Central

    Dong, Yaodong; Liu, Dongliang; Hu, Yue; Ma, Xiulan

    2015-01-01

    Aminoglycoside antibiotics such as gentamicin could cause ototoxicity in mammalians, by inducing oxidative stress and apoptosis in sensory hair cells of the cochlea. Sodium hydrosulfide (NaHS) is reported to alleviate oxidative stress and apoptosis, but its role in protecting aminoglycoside-induced hearing loss is unclear. In this study, we investigated the anti-oxidant and anti-apoptosis effect of NaHS in in vitro cultured House Ear Institute-Organ of Corti 1 (HEI-OC1) cells and isolated mouse cochlea. Results from cultured HEI-OC1 cells and cochlea consistently indicated that NaHS exhibited protective effects from gentamicin-induced ototoxicity, evident by maintained cell viability, hair cell number and cochlear morphology, reduced reactive oxygen species production and mitochondrial depolarization, as well as apoptosis activation of the intrinsic pathway. Moreover, in the isolated cochlear culture, NaHS was also demonstrated to protect the explant from gentamicin-induced mechanotransduction loss. Our study using multiple in vitro models revealed for the first time, the potential of NaHS as a therapeutic agent in protecting against aminoglycoside-induced hearing loss. PMID:26295804

  16. Alpha-chaconine, a potato glycoalkaloid, induces apoptosis of HT-29 human colon cancer cells through caspase-3 activation and inhibition of ERK 1/2 phosphorylation.

    PubMed

    Yang, Seun-Ah; Paek, Seung-Hwan; Kozukue, Nobuyuki; Lee, Kap-Rang; Kim, Jung-Ae

    2006-06-01

    Although alpha-chaconine, one of the two major potato trisaccharide glycoalkaloids, have shown cytotoxic effects on human cancer cells, the exact mechanism of this action of alpha-chaconine is not completely understood. In this study, we found that alpha-chaconine induced apoptosis of HT-29 cells in a time- and concentration-dependent manner by using flow cytometric analysis. We also found that caspase-3 activity and the active form of caspase-3 were increased 12 h after alpha-chaconine treatment. Caspase inhibitors, N-Ac-DEVD-CHO and Z-VAD-fmk, prevented alpha-chaconine-induced apoptosis, whereas alpha-chaconine-induced apoptosis was potentiated by PD98059, an extracellular signal-regulated kinase (ERK) inhibitor. However, pretreatment of the cells with LY294002 and SB203580, inhibitors of PI3K and p38, respectively, BAPTA-AM, an intracellular Ca(2+) chelator, and antioxidants such as N-acetylcysteine (NAC) and Trolox had no effect on the alpha-chaconine-induced cell death. In addition, phosphorylation of ERK was reduced by the treatment with alpha-chaconine. Moreover, alpha-chaconine-induced caspase-3 activity was further increased by the pretreatment with PD98059. Thus, the results indicate that alpha-chaconine induces apoptosis of HT-29 cells through inhibition of ERK and, in turn, activation of caspase-3.

  17. Unfolded Protein Response Promotes Doxorubicin-Induced Nonsmall Cell Lung Cancer Cells Apoptosis via the mTOR Pathway Inhibition.

    PubMed

    Zhao, Xiaofang; Yang, Yan; Yao, Fuli; Xiao, Bin; Cheng, Ying; Feng, Chunhong; Duan, Chunyan; Zhang, Chunyan; Liu, Youping; Li, Hong; Xiao, Bo; Dai, Rongyang

    2016-12-01

    Drug resistance is extremely common in nonsmall cell lung cancer (NSCLC) and is one of the major problems in NSCLC chemotherapy. However, the detailed mechanisms remain largely unknown. Unfolded protein response (UPR) is involved in the tumorigenesis of NSCLC. Here, the authors demonstrated that the UPR promotes poly (ADP-ribose) polymerase activation (PARP) cleavage in NSCLC cells on doxorubicin treatment, which is a hallmark of apoptosis and caspase activation. In NSCLC cells, doxorubicin treatment triggers the UPR activation, which subsequently promotes doxorubicin-mediated apoptosis. Importantly, mild endoplasmic reticulum stress precondition enhances the sensitivity of NSCLC cells to doxorubicin-initiated apoptosis. Furthermore, the eukaryotic translation initiation factor 2α (eIF2α) branch of the UPR is involved in the synergistic role of the UPR in NSCLC cell apoptosis on doxorubicin treatment. They also demonstrated that the mTOR pathway plays an essential role in synergistic induction of apoptosis by the UPR and doxorubicin in NSCLC cells. Taken together, these results provide a potential mechanism that the UPR promotes doxorubicin-induced apoptosis in NSCLC cells, at least in part, by eIF2α-mediated mTOR signal inactivation.

  18. Sorafenib inhibits endogenous and IL-6/S1P induced JAK2-STAT3 signaling in human neuroblastoma, associated with growth suppression and apoptosis.

    PubMed

    Yang, Fan; Jove, Veronica; Buettner, Ralf; Xin, Hong; Wu, Jun; Wang, Yan; Nam, Sangkil; Xu, Yibing; Ara, Tasnim; DeClerck, Yves A; Seeger, Robert; Yu, Hua; Jove, Richard

    2012-05-01

    Neuroblastoma is the most common extracranial solid tumor in the pediatric population. Sorafenib (Nexavar), a multikinase inhibitor, blocks cell proliferation and induces apoptosis in certain types of cancers. Here, we tested antitumor effects of sorafenib (≤ 10 µM) on four human neuroblastoma cell lines, CHLA255, CHLA171, CHLA90 and SK-N-AS. Sorafenib inhibited cell proliferation and induced apoptosis of neuroblastoma tumor cells in a dose-dependent manner. Sorafenib inhibited phosphorylation of Signal Transducer and Activator of Transcription 3 (STAT3) proteins at Tyr705 in these cells, associated with inhibition of phosphorylated JAK2, an upstream kinase that mediates STAT3 phosphorylation. Expression of a constitutively-activated STAT3 mutant (pSTAT3-C) partially blocked the antitumor effects of sorafenib on neuroblastoma cells. Sorafenib also inhibited the phosphorylation of STAT3 induced by IL-6 and sphingosine-1-phosphate (S1P), a recently identified regulator for STAT3, in these tumor cells. Moreover, sorafenib downregulated phosphorylation of MAPK (p44/42) in neuroblastoma cells, consistent with inhibition of their upstream regulators MEK1/2. Sorafenib inhibited expression of cyclin E, cyclin D1/D2/D3, key regulators for cell cycle, and the antiapoptotic proteins Mcl-1 and survivin. Finally, sorafenib suppressed the growth of human neuroblastoma cells in a mouse xenograft model. Taken together, these findings suggest the potential use of sorafenib for the treatment of pediatric neuroblastomas.

  19. Amorfrutin C Induces Apoptosis and Inhibits Proliferation in Colon Cancer Cells through Targeting Mitochondria.

    PubMed

    Weidner, Christopher; Rousseau, Morten; Micikas, Robert J; Fischer, Cornelius; Plauth, Annabell; Wowro, Sylvia J; Siems, Karsten; Hetterling, Gregor; Kliem, Magdalena; Schroeder, Frank C; Sauer, Sascha

    2016-01-22

    A known (1) and a structurally related new natural product (2), both belonging to the amorfrutin benzoic acid class, were isolated from the roots of Glycyrrhiza foetida. Compound 1 (amorfrutin B) is an efficient agonist of the nuclear peroxisome proliferator activated receptor (PPAR) gamma and of other PPAR subtypes. Compound 2 (amorfrutin C) showed comparably lower PPAR activation potential. Amorfrutin C exhibited striking antiproliferative effects for human colorectal cancer cells (HT-29 and T84), prostate cancer (PC-3), and breast cancer (MCF7) cells (IC50 values ranging from 8 to 16 μM in these cancer cell lines). Notably, amorfrutin C (2) showed less potent antiproliferative effects in primary colon cells. For HT-29 cells, compound 2 induced G0/G1 cell cycle arrest and modulated protein expression of key cell cycle modulators. Amorfrutin C further induced apoptotic events in HT-29 cells, including caspase activation, DNA fragmentation, PARP cleavage, phosphatidylserine externalization, and formation of reactive oxygen species. Mechanistic studies revealed that 2 disrupts the mitochondrial integrity by depolarization of the mitochondrial membrane (IC50 0.6 μM) and permanent opening of the mitochondrial permeability transition pore, leading to increased mitochondrial oxygen consumption and extracellular acidification. Structure-activity-relationship experiments revealed the carboxylic acid and the hydroxy group residues of 2 as fundamental structural requirements for inducing these apoptotic effects. Synergy analyses demonstrated stimulation of the death receptor signaling pathway. Taken together, amorfrutin C (2) represents a promising lead for the development of anticancer drugs.

  20. Infection of epithelial cells with Chlamydia trachomatis inhibits TNF-induced apoptosis at the level of receptor internalization while leaving non-apoptotic TNF-signalling intact.

    PubMed

    Waguia Kontchou, Collins; Tzivelekidis, Tina; Gentle, Ian E; Häcker, Georg

    2016-11-01

    Chlamydia trachomatis is an obligate intracellular bacterial pathogen of medical importance. C. trachomatis develops inside a membranous vacuole in the cytosol of epithelial cells but manipulates the host cell in numerous ways. One prominent effect of chlamydial infection is the inhibition of apoptosis in the host cell, but molecular aspects of this inhibition are unclear. Tumour necrosis factor (TNF) is a cytokine with important roles in immunity, which is produced by immune cells in chlamydial infection and which can have pro-apoptotic and non-apoptotic signalling activity. We here analysed the signalling through TNF in cells infected with C. trachomatis. The pro-apoptotic signal of TNF involves the activation of caspase-8 and is controlled by inhibitor of apoptosis proteins. We found that in C. trachomatis-infected cells, TNF-induced apoptosis was blocked upstream of caspase-8 activation even when inhibitor of apoptosis proteins were inhibited or the inhibitor of caspase-8 activation, cFLIP, was targeted by RNAi. However, when caspase-8 was directly activated by experimental over-expression of its upstream adapter Fas-associated protein with death domain, C. trachomatis was unable to inhibit apoptosis. Non-apoptotic TNF-signalling, particularly the activation of NF-κB, initiates at the plasma membrane, while the activation of caspase-8 and pro-apoptotic signalling occur subsequently to internalization of TNF receptor and the formation of a cytosolic signalling complex. In C. trachomatis-infected cells, NF-κB activation through TNF was unaffected, while the internalization of the TNF-TNF-receptor complex was blocked, explaining the lack of caspase-8 activation. These results identify a dichotomy of TNF signalling in C. trachomatis-infected cells: Apoptosis is blocked at the internalization of the TNF receptor, but non-apoptotic signalling through this receptor remains intact, permitting a response to this cytokine at sites of infection.

  1. Inhibition of protein kinase B activity induces cell cycle arrest and apoptosis during early G₁ phase in CHO cells.

    PubMed

    van Opstal, Angélique; Bijvelt, José; van Donselaar, Elly; Humbel, Bruno M; Boonstra, Johannes

    2012-04-01

    Inhibition of PKB (protein kinase B) activity using a highly selective PKB inhibitor resulted in inhibition of cell cycle progression only if cells were in early G1 phase at the time of addition of the inhibitor, as demonstrated by time-lapse cinematography. Addition of the inhibitor during mitosis up to 2 h after mitosis resulted in arrest of the cells in early G1 phase, as deduced from the expression of cyclins D and A and incorporation of thymidine. After 24 h of cell cycle arrest, cells expressed the cleaved caspase-3, a central mediator of apoptosis. These results demonstrate that PKB activity in early G1 phase is required to prevent the induction of apoptosis. Using antibodies, it was demonstrated that active PKB translocates to the nucleus during early G1 phase, while an even distribution of PKB was observed through cytoplasm and nucleus during the end of G1 phase.

  2. Water-Soluble Coenzyme Q10 Inhibits Nuclear Translocation of Apoptosis Inducing Factor and Cell Death Caused by Mitochondrial Complex I Inhibition

    PubMed Central

    Li, Haining; Chen, Guisheng; Ma, Wanrui; Li, Ping-An Andy

    2014-01-01

    The objectives of the study were to explore the mechanism of rotenone-induced cell damage and to examine the protective effects of water-soluble Coenzyme Q10 (CoQ10) on the toxic effects of rotenone. Murine hippocampal HT22 cells were cultured with mitochondrial complex I inhibitor rotenone. Water-soluble CoQ10 was added to the culture media 3 h prior to the rotenone incubation. Cell viability was determined by alamar blue, reactive oxygen species (ROS) production by dihydroethidine (DHE) and mitochondrial membrane potential by tetramethyl rhodamine methyl ester (TMRM). Cytochrome c, caspase-9 and apoptosis-inducing factor (AIF) were measured using Western blotting after 24 h rotenone incubation. Rotenone caused more than 50% of cell death, increased ROS production, AIF nuclear translocation and reduction in mitochondrial membrane potential, but failed to cause mitochondrial cytochrome c release and caspase-9 activation. Pretreatment with water-soluble CoQ10 enhanced cell viability, decreased ROS production, maintained mitochondrial membrane potential and prevented AIF nuclear translocation. The results suggest that rotenone activates a mitochondria-initiated, caspase-independent cell death pathway. Water-soluble CoQ10 reduces ROS accumulation, prevents the fall of mitochondrial membrane potential, and inhibits AIF translocation and subsequent cell death. PMID:25089873

  3. Pretreatment with Fucoidan from Fucus vesiculosus Protected against ConA-Induced Acute Liver Injury by Inhibiting Both Intrinsic and Extrinsic Apoptosis.

    PubMed

    Li, Jingjing; Chen, Kan; Li, Sainan; Liu, Tong; Wang, Fan; Xia, Yujing; Lu, Jie; Zhou, Yingqun; Guo, Chuanyong

    2016-01-01

    This study aimed to explore the effects of fucoidan from Fucus vesiculosus on concanavalin A (ConA)-induced acute liver injury in mice. Pretreatment with fucoidan protected liver function indicated by ALT, AST and histopathological changes by suppressing inflammatory cytokines, such as tumor necrosis factor alpha (TNF-α) and interferon gamma (IFN-γ). In addition, intrinsic and extrinsic apoptosis mediated by Bax, Bid, Bcl-2, Bcl-xL and Caspase 3, 8, and 9 were inhibited by fucoidan and the action was associated with the TRADD/TRAF2 and JAK2/STAT1 signal pathways. Our results demonstrated that fucoidan from Fucus vesiculosus alleviated ConA-induced acute liver injury via the inhibition of intrinsic and extrinsic apoptosis mediated by the TRADD/TRAF2 and JAK2/STAT1 pathways which were activated by TNF-α and IFN-γ. These findings could provide a potential powerful therapy for T cell-related hepatitis.

  4. Wogonin induces apoptosis and endoplasmic reticulum stress in HL-60 leukemia cells through inhibition of the PI3K-AKT signaling pathway.

    PubMed

    Hu, Chengjun; Xu, Maozhong; Qin, Rujuan; Chen, Weifeng; Xu, Xin

    2015-06-01

    Wogonin is a flavonoid isolated from Scutellaria baicalensis root and has multiple pharmacological effects, including anticancer effects. Recent studies have shown that wogonin induces cell cycle arrest and reverses multi-drug resistance in the human K562 leukemia cell line. However, its pharmacological function in the apoptosis of leukemia cells remains unknown. Therefore, we hypothesized that wogonin can induce apoptosis in the HL-60 leukemia cell line. In the present study, the HL-60 cells were treated with different doses of wogonin (0-150 µM). Wogonin inhibited the viability of HL-60 cells in a dose-dependent and time-dependent manner. Flow cytometry and analyses of caspase and PARP-1 activation and the Bax/Bcl-2 ratio, demonstrated that the cytotoxic effect of wogonin on HL-60 cells was mediated by caspase-dependent and mitochondrial-dependent apoptosis. Wogonin also induced the expression of certain members of the endoplasmic reticulum (ER) stress pathway (CHOP, GRP94 and GRP78) and the activation of multiple branches of ER stress transducers (IRE1α, PERK-eIF2α and ATF6) in the HL-60 cells. In addition, wogonin reduced the phosphorylation of PI3K and AKT in the HL-60 cells. Furthermore, constitutive activation of AKT induced by adenoviral vectors inhibited the pro-apoptotic effects and ER stress induced by wogonin in the HL-60 cells. In summary, our results indicated that wogonin induced apoptosis and ER stress in HL-60 cells, which was mediated by the inhibition of the PI3K-AKT signaling pathway.

  5. L-Ascorbate Protects Against Methamphetamine-Induced Neurotoxicity of Cortical Cells via Inhibiting Oxidative Stress, Autophagy, and Apoptosis.

    PubMed

    Huang, Ya-Ni; Yang, Ling-Yu; Wang, Jing-Ya; Lai, Chien-Cheng; Chiu, Chien-Tsai; Wang, Jia-Yi

    2017-01-01

    Methamphetamine (METH)-induced cell death contributes to the pathogenesis of neurotoxicity; however, the relative roles of oxidative stress, apoptosis, and autophagy remain unclear. L-Ascorbate, also called vitamin (Vit.) C, confers partial protection against METH neurotoxicity via induction of heme oxygenase-1. We further investigated the role of Vit. C in METH-induced oxidative stress, apoptosis, and autophagy in cortical cells. Exposure to lower concentrations (0.1, 0.5, 1 mM) of METH had insignificant effects on ROS production, whereas cells exposed to 5 mM METH exhibited ROS production in a time-dependent manner. We confirmed METH-induced apoptosis (by nuclear morphology revealed by Hoechst 33258 staining and Western blot showing the protein levels of pro-caspase 3 and cleaved caspase 3) and autophagy (by Western blot showing the protein levels of Belin-1 and conversion of microtubule-associated light chain (LC)3-I to LC3-II and autophagosome staining by monodansylcadaverine). The apoptosis as revealed by cleaved caspase-3 expression marked an increase at 18 h after METH exposure while both autophagic markers, Beclin 1 and LC3-II, marked an increase in cells exposed to METH for 6 and 24 h, respectively. Treating cells with Vit. C 30 min before METH exposure time-dependently attenuated the production of ROS. Vitamin C also attenuated METH-induced Beclin 1 and LC3-II expression and METH toxicity. Treatment of cells with Vit. C before METH exposure attenuated the expression of cleaved caspase-3 and reduced the number of METH-induced apoptotic cells. We suggest that the protective effect of Vit. C against METH toxicity might be through attenuation of ROS production, autophagy, and apoptosis.

  6. PEDF and 34-mer inhibit angiogenesis in the heart by inducing tip cells apoptosis via up-regulating PPAR-γ to increase surface FasL.

    PubMed

    Zhang, Hao; Wei, Tengteng; Jiang, Xia; Li, Zhimin; Cui, Huazhu; Pan, Jiajun; Zhuang, Wei; Sun, Teng; Liu, Zhiwei; Zhang, Zhongming; Dong, Hongyan

    2016-01-01

    Pigment epithelial-derived factor (PEDF) is a potent anti-angiogenic factor whose effects are partially mediated through the induction of endothelial cell apoptosis. However, the underlying mechanism for PEDF and the functional PEDF peptides 34-mer and 44-mer to inhibit angiogenesis in the heart has not been fully established. In the present study, by constructing adult Sprague-Dawley rat models of acute myocardial infarction (AMI) and in vitro myocardial angiogenesis, we showed that PEDF and 34-mer markedly inhibits angiogenesis by selectively inducing tip cells apoptosis rather than quiescent cells. Peptide 44-mer on the other hand exhibits no such effects. Next, we identified Fas death pathway as essential downstream regulators of PEDF and 34-mer activities in inhibiting angiogenesis. By using peroxisome proliferator-activated receptor γ (PPAR-γ) siRNA and PPAR-γ inhibitor, GW9662, we found the effects of PEDF and 34-mer were extensively blocked. These data suggest that PEDF and 34-mer inhibit angiogenesis via inducing tip cells apoptosis at least by means of up-regulating PPAR-γ to increase surface FasL in the ischemic heart, which might be a novel mechanism to understanding cardiac angiogenesis after AMI.

  7. Isoorientin induces apoptosis through mitochondrial dysfunction and inhibition of PI3K/Akt signaling pathway in HepG2 cancer cells

    SciTech Connect

    Yuan, Li; Wang, Jing; Xiao, Haifang; Xiao, Chunxia; Wang, Yutang; Liu, Xuebo

    2012-11-15

    Isoorientin (ISO) is a flavonoid compound that can be extracted from several plant species, such as Phyllostachys pubescens, Patrinia, and Drosophyllum lusitanicum; however, its biological activity remains poorly understood. The present study investigated the effects and putative mechanism of apoptosis induced by ISO in human hepatoblastoma cancer (HepG2) cells. The results showed that ISO induced cell death in a dose-dependent manner in HepG2 cells, but no toxicity in human liver cells (HL-7702) and buffalo rat liver cells (BRL-3A) treated with ISO at the indicated concentrations. ISO-induced cell death included apoptosis which characterized by the appearance of nuclear shrinkage, the cleavage of poly (ADP-ribose) polymerase (PARP) and DNA fragmentation. ISO significantly (p < 0.01) increased the Bax/Bcl-2 ratio, disrupted the mitochondrial membrane potential (MMP), increased the release of cytochrome c, activated caspase-3, and enhanced intracellular levels of reactive oxygen species (ROS) and nitric oxide (NO). In addition, ISO effectively inhibited the phosphorylation of Akt and increased FoxO4 expression. The PI3K/Akt inhibitor LY294002 enhanced the apoptosis-inducing effect of ISO. However, LY294002 markedly quenched ROS and NO generation and diminished the protein expression of heme peroxidase enzyme (HO-1) and inducible nitric oxide synthase (iNOS). Furthermore, the addition of a ROS inhibitor (N-acetyl cysteine, NAC) or iNOS inhibitor (N-[3-(aminomethyl) benzyl] acetamidine, dihydrochloride, 1400W) significantly diminished the apoptosis induced by ISO and also blocked the phosphorylation of Akt. These results demonstrated for the first time that ISO induces apoptosis in HepG2 cells and indicate that this apoptosis might be mediated through mitochondrial dysfunction and PI3K/Akt signaling pathway, and has no toxicity in normal liver cells, suggesting that ISO may have good potential as a therapeutic and chemopreventive agent for liver cancer. Highlights:

  8. Inhibition of NF-κB activation sensitizes U937 cells to 3′-azido-3′-deoxythymidine induced apoptosis

    PubMed Central

    Matteucci, C; Minutolo, A; Balestrieri, E; Marino-Merlo, F; Bramanti, P; Garaci, E; Macchi, B; Mastino, A

    2010-01-01

    In this study, we investigated molecular mechanisms underlying low susceptibility to apoptosis induced by the nucleoside analog azidothymidine (AZT) and the role of nuclear factor-κB (NF-κB) activation in these phenomena. A preliminary screening in different cell lines indicated U937 monocytic cell line as suitable to this purpose. Treatment of U937 cells even with suprapharmacological concentrations of AZT induced only moderate levels of apoptosis. Surprisingly, SuperArray analysis showed that AZT induced the transcriptional activity of both pro- and anti-apoptotic genes. Interestingly, moreover, several genes upregulated by AZT were NF-κB related. In fact, AZT, after an initial inhibition of NF-κB activation with respect to control, induced a transient, but consistent, increase in NF-κB-binding activity. Inhibition of NF-κB activation in U937 cells, stably transfected with a dominant-negative IκBα or by pharmacological treatment, sensitized them to apoptosis induced by AZT and impaired the upregulation of anti-apoptotic genes in response to AZT treatment, with respect to control cells. These results indicate that NF-κB activation by AZT has a role in protecting target cells from apoptotic cell death, improving our understanding of the toxicology and the therapeutic usage of this drug. PMID:21368854

  9. CaMKII inhibition in type II pneumocytes protects from bleomycin-induced pulmonary fibrosis by preventing Ca2+-dependent apoptosis.

    PubMed

    Winters, Christopher J; Koval, Olha; Murthy, Shubha; Allamargot, Chantal; Sebag, Sara C; Paschke, John D; Jaffer, Omar A; Carter, A Brent; Grumbach, Isabella M

    2016-01-01

    The calcium and calmodulin-dependent kinase II (CaMKII) translates increases in intracellular Ca(2+) into downstream signaling events. Its function in pulmonary pathologies remains largely unknown. CaMKII is a well-known mediator of apoptosis and regulator of endoplasmic reticulum (ER) Ca(2+). ER stress and apoptosis of type II pneumocytes lead to aberrant tissue repair and progressive collagen deposition in pulmonary fibrosis. Thus we hypothesized that CaMKII inhibition alleviates fibrosis in response to bleomycin by attenuating apoptosis and ER stress of type II pneumocytes. We first established that CaMKII was strongly expressed in the distal respiratory epithelium, in particular in surfactant protein-C-positive type II pneumocytes, and activated after bleomycin instillation. We generated a novel transgenic model of inducible expression of the CaMKII inhibitor peptide AC3-I limited to type II pneumocytes (Tg SPC-AC3-I). Tg SPC-AC3-I mice were protected from development of pulmonary fibrosis after bleomycin exposure compared with wild-type mice. CaMKII inhibition also provided protection from apoptosis in type II pneumocytes in vitro and in vivo. Moreover, intracellular Ca(2+) levels and ER stress were increased by bleomycin and significantly blunted with CaMKII inhibition in vitro. These data demonstrate that CaMKII inhibition prevents type II pneumocyte apoptosis and development of pulmonary fibrosis in response to bleomycin. CaMKII inhibition may therefore be a promising approach to prevent or ameliorate the progression of pulmonary fibrosis.

  10. The cannabinoid delta(9)-tetrahydrocannabinol inhibits RAS-MAPK and PI3K-AKT survival signalling and induces BAD-mediated apoptosis in colorectal cancer cells.

    PubMed

    Greenhough, Alexander; Patsos, Helena A; Williams, Ann C; Paraskeva, Christos

    2007-11-15

    Deregulation of cell survival pathways and resistance to apoptosis are widely accepted to be fundamental aspects of tumorigenesis. As in many tumours, the aberrant growth and survival of colorectal tumour cells is dependent upon a small number of highly activated signalling pathways, the inhibition of which elicits potent growth inhibitory or apoptotic responses in tumour cells. Accordingly, there is considerable interest in therapeutics that can modulate survival signalling pathways and target cancer cells for death. There is emerging evidence that cannabinoids, especially Delta(9)-tetrahydrocannabinol (THC), may represent novel anticancer agents, due to their ability to regulate signalling pathways critical for cell growth and survival. Here, we report that CB1 and CB2 cannabinoid receptors are expressed in human colorectal adenoma and carcinoma cells, and show for the first time that THC induces apoptosis in colorectal cancer cells. THC-induced apoptosis was rescued by pharmacological blockade of the CB1, but not CB2, cannabinoid receptor. Importantly, THC treatment resulted in CB1-mediated inhibition of both RAS-MAPK/ERK and PI3K-AKT survival signalling cascades; two key cell survival pathways frequently deregulated in colorectal tumours. The inhibition of ERK and AKT activity by THC was accompanied by activation of the proapoptotic BCL-2 family member BAD. Reduction of BAD protein expression by RNA interference rescued colorectal cancer cells from THC-induced apoptosis. These data suggest an important role for CB1 receptors and BAD in the regulation of apoptosis in colorectal cancer cells. The use of THC, or selective targeting of the CB1 receptor, may represent a novel strategy for colorectal cancer therapy.

  11. Inhibition of autophagy with chloroquine potentiates carfilzomib-induced apoptosis in myeloma cells in vitro and in vivo.

    PubMed

    Jarauta, Vidal; Jaime, Paula; Gonzalo, Oscar; de Miguel, Diego; Ramírez-Labrada, Ariel; Martínez-Lostao, Luis; Anel, Alberto; Pardo, Julián; Marzo, Isabel; Naval, Javier

    2016-11-01

    The proteasome inhibitor bortezomib is now the cornerstone of combination therapy of multiple myeloma (MM). Carfilzomib, a second-generation inhibitor, has shown a substantial benefit vs bortezomib in combination regimes. Here we have analyzed in detail the mechanism of cell death induced by carfilzomib and its crosstalk with autophagy and applied the results to the in vivo treatment of MM in a mouse model. Carfilzomib induced apoptosis essentially by the intrinsic pathway, through the up-regulation of Puma and Noxa proteins followed by the interaction of Puma, Noxa and Bim with Bax and of Noxa with Bak. Carfilzomib also produces an increase in the formation of autophagosomes but, as apoptosis progresses, autophagy is disrupted, probably owing to Beclin 1 and p62 inactivation. Cotreatment with chloroquine, which blocks autophagy, strongly potentiated apoptosis in vitro and in vivo. Accordingly, combination therapy with carfilzomib plus chloroquine was highly effective in the treatment of MM in a mouse xenograft model. Chloroquine also enhanced carfilzomib-induced calreticulin exposure in MM cells undergoing apoptosis, increasing the immunogenic ability of carfilzomib. These results support design of trials combining carfilzomib with chloroquine to improve MM therapy.

  12. Curcumol Inhibits Growth and Induces Apoptosis of Colorectal Cancer LoVo Cell Line via IGF-1R and p38 MAPK Pathway

    PubMed Central

    Wang, Juan; Huang, Fengxiang; Bai, Zhun; Chi, Bixia; Wu, Jiacai; Chen, Xu

    2015-01-01

    Curcumol, isolated from the traditional medical plant Rhizoma Curcumae, is the bioactive component of Zedoary oil, whose potential anti-tumor effect has attracted considerable attention in recent years. Though many researchers have reported curcumol and its bioactivity, the potential molecular mechanism for its anti-cancer effect in colorectal cancer LoVo cells still remains unclear. In the present study, we found that curcumol showed growth inhibition and induced apoptosis of LoVo cells in a dose- and time-dependent manner. The occurrence of its proliferation inhibition and apoptosis came with suppression of IGF-1R expression, and then increased the phosphorylation of p38 mitogen activated protein kinase (MAPK), which might result in a cascade response by inhibiting the CREB survival pathway and finally triggered Bax/Bcl-2 and poly(ADP-ribose) polymerase 1 (PARP-1) apoptosis signals. Moreover, curcumol inhibited colorectal cancer in xenograft models of nude mice. Immunohistochemical and Western blot analysis revealed that curcumol could decrease the expression of ki-67, Bcl-2 as well as CREB1, and increase the expression of Bax and the phosphorylation of p38, which were consistent with our in vitro study. Overall, our in vitro and in vivo data confirmed the anti-cancer activity of curcumol, which was related to a significant inhibition of IGF-1R and activation of p38 MAPKs, indicating that curcumol may be a potential anti-tumor agent for colorectal carcinoma therapy. PMID:26307972

  13. Curcumol Inhibits Growth and Induces Apoptosis of Colorectal Cancer LoVo Cell Line via IGF-1R and p38 MAPK Pathway.

    PubMed

    Wang, Juan; Huang, Fengxiang; Bai, Zhun; Chi, Bixia; Wu, Jiacai; Chen, Xu

    2015-08-20

    Curcumol, isolated from the traditional medical plant Rhizoma Curcumae, is the bioactive component of Zedoary oil, whose potential anti-tumor effect has attracted considerable attention in recent years. Though many researchers have reported curcumol and its bioactivity, the potential molecular mechanism for its anti-cancer effect in colorectal cancer LoVo cells still remains unclear. In the present study, we found that curcumol showed growth inhibition and induced apoptosis of LoVo cells in a dose- and time-dependent manner. The occurrence of its proliferation inhibition and apoptosis came with suppression of IGF-1R expression, and then increased the phosphorylation of p38 mitogen activated protein kinase (MAPK), which might result in a cascade response by inhibiting the CREB survival pathway and finally triggered Bax/Bcl-2 and poly(ADP-ribose) polymerase 1 (PARP-1) apoptosis signals. Moreover, curcumol inhibited colorectal cancer in xenograft models of nude mice. Immunohistochemical and Western blot analysis revealed that curcumol could decrease the expression of ki-67, Bcl-2 as well as CREB1, and increase the expression of Bax and the phosphorylation of p38, which were consistent with our in vitro study. Overall, our in vitro and in vivo data confirmed the anti-cancer activity of curcumol, which was related to a significant inhibition of IGF-1R and activation of p38 MAPKs, indicating that curcumol may be a potential anti-tumor agent for colorectal carcinoma therapy.

  14. Curcumin inhibits cell growth and induces cell apoptosis through upregulation of miR-33b in gastric cancer.

    PubMed

    Sun, Qianqian; Zhang, Wenjing; Guo, Yanjie; Li, Zhuyao; Chen, Xiaonan; Wang, Yuanyuan; Du, Yuwen; Zang, Wenqiao; Zhao, Guoqiang

    2016-10-01

    In this work, the in vitro experiments about biological mechanisms of curcumin were conducted using the gastric cancer cell lines SGC-7901 and BGC-823. After 24-h exposure to curcumin at the concentrations of 5, 10, 15, 20, and 40 μmol/L, two cells showed the decreased proliferation and increased apoptosis abilities. Real-time PCR, Cell Counting Kit-8 (CCK-8) assay, western blotting, and cell apoptosis assay were used to further study the underlying mechanisms of curcumin. The first stage of our studies showed that curcumin affected the expression of miR-33b, which, in turn, affected the expression of the X-linked inhibitor of apoptosis protein (XIAP) messenger RNA (mRNA). Next, curcumin was also identified to regulate the proliferation and apoptosis of SGC-7901 and BGC-823 cells. Further bioinformatics analysis and luciferase reporter assays proved that XIAP was one of the target genes of miR-33b. In the next stage, SGC-7901 and BGC-823 cells were treated with 20 μL curcumin, miR-33b mimics, and small interfering RNA (siRNA) of XIAP, respectively. The results showed that curcumin had similar effects on cell growth and apoptosis as the upregulation of miR-33b and the upregulation of the siRNA of XIAP. The results that followed from the restore experiments showed that curcumin affected cell growth and apoptosis presumably by upregulating the XIAP targeting in gastric cancer. Collectively, our results indicate that curcumin-miR-33b-XIAP coupling might be an important mechanism by which curcumin induces the apoptosis of SGC-7901 and BGC-823 cells.

  15. The novel tetramethylpyrazine bis-nitrone (TN-2) protects against MPTP/MPP+-induced neurotoxicity via inhibition of mitochondrial-dependent apoptosis.

    PubMed

    Xu, Daping; Duan, Hongwei; Zhang, Zaijun; Cui, Wei; Wang, Liang; Sun, Yewei; Lang, Ming; Hoi, Pui Man; Han, Yifan; Wang, Yuqiang; Lee, Simon MingYuen

    2014-03-01

    Mitochondrial-dependent apoptosis plays an important role in the degeneration of dopaminergic neurons in Parkinson's disease (PD). Methyl-4-phenyl-1,2,3,6-tetra- hydropyridine (MPTP), the most widely used neurotoxin to simulate PD, is converted to 1-methyl-4-phenylpyridinium (MPP(+)) in vivo. MPP(+) induces excessive intracellular reactive oxygen species (ROS), leading to mitochondrial-dependent apoptosis via sequentially opening mitochondria permeability transition pore (mPTP) to release cytochrome c from mitochondria into cytoplasm and activate pro-apoptotic caspase proteins. We have previously synthesized 2,5-[[(1,1-dimethylethyl)oxidoimino]methyl]-3,6-trimethylpyrazine (TN-2), a novel derivative of the Chinese herb medicine tetramethylpyrazine (TMP). TN-2 is armed with two powerful free radical-scavenging nitrone moieties. TN-2 significantly reversed the loss of dopaminergic neurons in the substantia nigra and the decrease in dopamine level in the striatum induced by MPTP in mice. TN-2 ameliorated the MPTP-induced decrease of brain superoxide dismutase activity and glutathione concentration and increase of brain malondialdehyde. In addition, TN-2 inhibited MPP(+)-induced neuronal damage/apoptosis in primary cerebellum granular neurons (CGNs) and SH-SY5Y cells. TN-2 decreased excessive intracellular ROS, prevented the loss of mitochondrial membrane potential, blocked the release of mitochondrial cytochrome c and inhibited the activation of caspase-3 and caspase-9. Moreover, TN-2 treatment increased the mRNA expression of mitochondrial biogenesis factors peroxisome proliferator-activated receptor (PPAR)-γ coactivator-1 (PGC- 1α and β) and mitochondrial transcription factor A (Tfam) in SH-SY5Y cells and CGNs. These results suggest that TN-2 protects dopaminergic neurons against MPTP/MPP(+)-induced neurotoxicity via the inhibition of mitochondrial-dependent apoptosis and possibly via the activation of mitochondrial biogenesis, indicating that TN-2 is a potential

  16. [6]-Gingerol induces caspase-dependent apoptosis and prevents PMA-induced proliferation in colon cancer cells by inhibiting MAPK/AP-1 signaling.

    PubMed

    Radhakrishnan, E K; Bava, Smitha V; Narayanan, Sai Shyam; Nath, Lekshmi R; Thulasidasan, Arun Kumar T; Soniya, Eppurathu Vasudevan; Anto, Ruby John

    2014-01-01

    We report mechanism-based evidence for the anticancer and chemopreventive efficacy of [6]-gingerol, the major active principle of the medicinal plant, Ginger (Zingiber officinale), in colon cancer cells. The compound was evaluated in two human colon cancer cell lines for its cytotoxic effect and the most sensitive cell line, SW-480, was selected for the mechanistic evaluation of its anticancer and chemopreventive efficacy. The non-toxic nature of [6]-gingerol was confirmed by viability assays on rapidly dividing normal mouse colon cells. [6]-gingerol inhibited cell proliferation and induced apoptosis as evidenced by externalization of phosphatidyl serine in SW-480, while the normal colon cells were unaffected. Sensitivity to [6]-gingerol in SW-480 cells was associated with activation of caspases 8, 9, 3 &7 and cleavage of PARP, which attests induction of apoptotic cell death. Mechanistically, [6]-gingerol down-regulated Phorbol Myristate Acetate (PMA) induced phosphorylation of ERK1/2 and JNK MAP kinases and activation of AP-1 transcription factor, but had only little effects on phosphorylation of p38 MAP kinase and activation of NF-kappa B. Additionally, it complemented the inhibitors of either ERK1/2 or JNK MAP kinase in bringing down the PMA-induced cell proliferation in SW-480 cells. We report the inhibition of ERK1/2/JNK/AP-1 pathway as a possible mechanism behind the anticancer as well as chemopreventive efficacy of [6]-gingerol against colon cancer.

  17. ERK inhibition sensitizes cancer cells to oleanolic acid-induced apoptosis through ERK/Nrf2/ROS pathway.

    PubMed

    Liu, Jia; Ma, Leina; Chen, Xiao; Wang, Jianxun; Yu, Tao; Gong, Ying; Ma, Aiguo; Zheng, Lanhong; Liang, Hui

    2016-06-01

    Oleanolic acid (OA) is a natural triterpenoid that is widely distributed in edible and medicinal plants. OA exerts anti-tumor activity on a wide range of cancer cells primarily through inducing apoptosis. Dysregulated ERK signaling is closely complicated in the biology of cancer, such as metastasis, proliferation, and survival, and it can be activated by various stimuli. In this study, we found that OA induced the activation of ERK in cancer cells. ERK activation compromised the apoptosis induced by OA. Blocking ERK activation by U0126 or siRNAs was able to potentiate the pro-apoptotic activity of OA on cancer cells. OA was shown to promote ERK-dependent Nrf2 expression in cancer cells, and in turn, Nrf2 expression was able to suppress OA-induced ROS generation. Blockade of Nrf2 expression was able to increase ROS levels and apoptotic death in cancer cells. In conclusion, we provided evidences that ERK activation is a mechanism underlying the resistance of cancer cells to OA-induced apoptosis and targeting ERK is a promising strategy to enhance the anti-tumor efficacy of OA.

  18. Edaravone protects against oxygen-glucose-serum deprivation/restoration-induced apoptosis in spinal cord astrocytes by inhibiting integrated stress response

    PubMed Central

    Dai, Bin; Yan, Ting; Shen, Yi-xing; Xu, You-jia; Shen, Hai-bin; Chen, Dong; Wang, Jin-rong; He, Shuang-hua; Dong, Qi-rong; Zhang, Ai-liang

    2017-01-01

    We previously found that oxygen-glucose-serum deprivation/restoration (OGSD/R) induces apoptosis of spinal cord astrocytes, possibly via caspase-12 and the integrated stress response, which involves protein kinase R-like endoplasmic reticulum kinase (PERK), eukaryotic initiation factor 2-alpha (eIF2α) and activating transcription factor 4 (ATF4). We hypothesized that edaravone, a low molecular weight, lipophilic free radical scavenger, would reduce OGSD/R-induced apoptosis of spinal cord astrocytes. To test this, we established primary cultures of rat astrocytes, and exposed them to 8 hours/6 hours of OGSD/R with or without edaravone (0.1, 1, 10, 100 μM) treatment. We found that 100 μM of edaravone significantly suppressed astrocyte apoptosis and inhibited the release of reactive oxygen species. It also inhibited the activation of caspase-12 and caspase-3, and reduced the expression of homologous CCAAT/enhancer binding protein, phosphorylated (p)-PERK, p-eIF2α, and ATF4. These results point to a new use of an established drug in the prevention of OGSD/R-mediated spinal cord astrocyte apoptosis via the integrated stress response.

  19. Physapubescin selectively induces apoptosis in VHL-null renal cell carcinoma cells through down-regulation of HIF-2α and inhibits tumor growth.

    PubMed

    Chen, Lixia; Xia, Guiyang; Qiu, Feng; Wu, Chunli; Denmon, Andria P; Zi, Xiaolin

    2016-09-01

    We have purified physapubescin, a predominant steroidal lactone, from medicinal plant Physalis pubescens L., commonly named as "hairy groundcherry" in English and "Deng-Long-Cao" in Chinese. Von Hippel-Lindau (VHL)-null 786-O, RCC4 and A498 Renal Cell Carcinoma (RCC) cell lines expressing high levels of Hypoxia Inducible Factor (HIF)-2α are more sensitive to physapubescin-mediated apoptosis and growth inhibitory effect than VHL wild-type Caki-2 and ACHN RCC cell lines. Restoration of VHL in RCC4 cells attenuated the growth inhibitory effect of physapubescin. Physapubescin decreases the expression of HIF-2α and increases the expression of CCAAT/enhancer-binding protein homologus protein (CHOP), which leads to up-regulation of death receptor 5 (DR5), activation of caspase-8 and -3, cleavage of poly (ADP-Ribose) polymerase (PARP) and apoptosis. Under hypoxia conditions, the apoptotic and growth inhibitory effects of physapubescin are further enhanced. Additionally, physapubescin synergizes with TNF-related apoptosis-inducing ligand (TRAIL) for markedly enhanced induction of apoptosis in VHL-null 786-O cells but not in VHL wild-type Caki-2 cells. Physapubescin significantly inhibited in vivo angiogenesis in the 786-O xenograft. Physapubescin as a novel agent for elimination of VHL-null RCC cells via apoptosis is warranted for further investigation.

  20. Physapubescin selectively induces apoptosis in VHL-null renal cell carcinoma cells through down-regulation of HIF-2α and inhibits tumor growth

    PubMed Central

    Chen, Lixia; Xia, Guiyang; Qiu, Feng; Wu, Chunli; Denmon, Andria P.; Zi, Xiaolin

    2016-01-01

    We have purified physapubescin, a predominant steroidal lactone, from medicinal plant Physalis pubescens L., commonly named as “hairy groundcherry” in English and “Deng-Long-Cao” in Chinese. Von Hippel-Lindau (VHL)-null 786-O, RCC4 and A498 Renal Cell Carcinoma (RCC) cell lines expressing high levels of Hypoxia Inducible Factor (HIF)-2α are more sensitive to physapubescin-mediated apoptosis and growth inhibitory effect than VHL wild-type Caki-2 and ACHN RCC cell lines. Restoration of VHL in RCC4 cells attenuated the growth inhibitory effect of physapubescin. Physapubescin decreases the expression of HIF-2α and increases the expression of CCAAT/enhancer-binding protein homologus protein (CHOP), which leads to up-regulation of death receptor 5 (DR5), activation of caspase-8 and -3, cleavage of poly (ADP-Ribose) polymerase (PARP) and apoptosis. Under hypoxia conditions, the apoptotic and growth inhibitory effects of physapubescin are further enhanced. Additionally, physapubescin synergizes with TNF-related apoptosis-inducing ligand (TRAIL) for markedly enhanced induction of apoptosis in VHL-null 786-O cells but not in VHL wild-type Caki-2 cells. Physapubescin significantly inhibited in vivo angiogenesis in the 786-O xenograft. Physapubescin as a novel agent for elimination of VHL-null RCC cells via apoptosis is warranted for further investigation. PMID:27581364

  1. Fermented wheat germ extract inhibits glycolysis/pentose cycle enzymes and induces apoptosis through poly(ADP-ribose) polymerase activation in Jurkat T-cell leukemia tumor cells.

    PubMed

    Comin-Anduix, Begona; Boros, Laszlo G; Marin, Silvia; Boren, Joan; Callol-Massot, Carles; Centelles, Josep J; Torres, Josep L; Agell, Neus; Bassilian, Sara; Cascante, Marta

    2002-11-29

    The fermented extract of wheat germ, trade name Avemar, is a complex mixture of biologically active molecules with potent anti-metastatic activities in various human malignancies. Here we report the effect of Avemar on Jurkat leukemia cell viability, proliferation, cell cycle distribution, apoptosis, and the activity of key glycolytic/pentose cycle enzymes that control carbon flow for nucleic acid synthesis. The cytotoxic IC(50) concentration of Avemar for Jurkat tumor cells is 0.2 mg/ml, and increasing doses of the crude powder inhibit Jurkat cell proliferation in a dose-dependent fashion. At concentrations higher than 0.2 mg/ml, Avemar inhibits cell growth by more than 50% (72 h of incubation), which is preceded by the appearance of a sub-G(1) peak on flow histograms at 48 h. Laser scanning cytometry of propidium iodide- and annexin V-stained cells indicated that the growth-inhibiting effect of Avemar was consistent with a strong induction of apoptosis. Inhibition by benzyloxycarbonyl-Val-Ala-Asp fluoromethyl ketone of apoptosis but increased proteolysis of poly(ADP-ribose) indicate caspases mediate the cellular effects of Avemar. Activities of glucose-6-phosphate dehydrogenase and transketolase were inhibited in a dose-dependent fashion, which correlated with decreased (13)C incorporation and pentose cycle substrate flow into RNA ribose. This decrease in pentose cycle enzyme activities and carbon flow toward nucleic acid precursor synthesis provide the mechanistic understanding of the cell growth-controlling and apoptosis-inducing effects of fermented wheat germ. Avemar exhibits about a 50-fold higher IC(50) (10.02 mg/ml) for peripheral blood lymphocytes to induce a biological response, which provides the broad therapeutic window for this supplemental cancer treatment modality with no toxic effects.

  2. A novel curcumin derivative which inhibits P-glycoprotein, arrests cell cycle and induces apoptosis in multidrug resistance cells.

    PubMed

    Lopes-Rodrigues, Vanessa; Oliveira, Ana; Correia-da-Silva, Marta; Pinto, Madalena; Lima, Raquel T; Sousa, Emília; Vasconcelos, M Helena

    2017-01-15

    Cancer multidrug resistance (MDR) is a major limitation to the success of cancer treatment and is highly associated with the overexpression of drug efflux pumps such as P-glycoprotein (P-gp). In order to achieve more effective chemotherapeutic treatments, it is important to develop P-gp inhibitors to block/decrease its activity. Curcumin (1) is a secondary metabolite isolated from the turmeric of Curcuma longa L.. Diverse biological activities have been identified for this compound, particularly, MDR modulation in various cancer cell models. However, curcumin (1) has low chemical stability, which severely limits its application. In order to improve stability and P-gp inhibitory effect, two potential more stable curcumin derivatives were synthesized as building blocks, followed by several curcumin derivatives. These compounds were then analyzed in terms of antitumor and anti-P-gp activity, in two MDR and sensitive tumor lines (from chronic myeloid leukemia and non-small cell lung cancer). We identified from a series of curcumin derivatives a novel curcumin derivative (1,7-bis(3-methoxy-4-(prop-2-yn-1-yloxy)phenyl)hepta-1,6-diene-3,5-dione, 10) with more potent antitumor and anti-P-gp activity than curcumin (1). This compound (10) was shown to promote cell cycle arrest (at the G2/M phase) and induce apoptosis in the MDR chronic myeloid leukemia cell line. Therefore it is a really interesting P-gp inhibitor due to its ability to inhibit both P-gp function and expression.

  3. Overexpression of cellular repressor of E1A-stimulated genes inhibits TNF-{alpha}-induced apoptosis via NF-{kappa}B in mesenchymal stem cells

    SciTech Connect

    Peng, Cheng-Fei; Han, Ya-Ling; Jie-Deng,; Yan, Cheng-Hui; Jian-Kang,; Bo-Luan,; Jie-Li

    2011-03-25

    Research highlights: {yields} CREG protected MSCs from tumor necrosis factor-{alpha} (TNF-{alpha}) induced apoptosis. {yields} CREG inhibits the phosphorylation of I{kappa}B{alpha} and prevents the activation of NF-{kappa}B. {yields} CREG inhibits NF-{kappa}B nuclear translocation and pro-apoptosis protein transcription. {yields} CREG anti-apoptotic effect involves inhibition of the death receptor pathway. {yields} p53 is downregulated by CREG via NF-{kappa}B pathway under TNF-{alpha} stimulation. -- Abstract: Bone marrow-derived mesenchymal stem cells (MSCs) show great potential for therapeutic repair after myocardial infarction. However, poor viability of transplanted MSCs in the ischemic heart has limited their use. Cellular repressor of E1A-stimulated genes (CREG) has been identified as a potent inhibitor of apoptosis. This study therefore aimed to determine if rat bone marrow MSCs transfected with CREG-were able to effectively resist apoptosis