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Sample records for synergistically induces apoptosis

  1. Synergistic apoptosis-inducing effect of aspirin and isosorbide mononitrate on human colon cancer cells.

    PubMed

    Wang, Xiaodong; Diao, Yuwen; Liu, Yu; Gao, Ningning; Gao, Dong; Wan, Yanyan; Zhong, Jingjing; Jin, Guangyi

    2015-09-01

    Aspirin and isosorbide mononitrate (ISMN) are two commonly used drugs, which are clinically applied for the treatment of inflammatory and cardiovascular diseases, respectively. Recently, aspirin has attracted interest due to its potential application for the treatment of cancer, particularly colon cancer. NO-aspirin, an aspirin derivative containing a covalently bound NO-donating moiety, has been proven to be an effective anti‑tumor agent with apoptosis-inducing ability. In the present study, ISMN was used as an NO donor and its synergic effect with aspirin was assessed in human colon cancer cells. In vitro, an MTT assay demonstrated that ISMN had a synergistic effect on the growth inhibitory effects of aspirin on HCT116 and SW620 colon cancer cells, while the growth of EA.hy926 normal endothelial cells was unaffected. This synergistic anti‑tumor effect was further validated in vivo using nude mouse HCT116 cell xenograft model. Observation of nuclear morphology, Annexin V-fluorescein isothiocyanate/propidium iodide double staining and a caspase-3 activity assay suggested that the combination of the two drugs induced apoptosis in HCT116 cells. Furthermore, the molecular mechanisms of the apoptotic effect of the drugs was assessed using an NO release assay, reverse transcription quantitative polymerase chain reaction analysis, western blot analysis and a luciferase reporter assay. It was certified that the increase in the amount of NO release, the decrease in the luciferase promoter activity and the expression of cyclin D1 and c-myc in HCT116 cells were affected by aspirin and ISMN in a synergistic manner. In conclusion, the present study was the first, to the best of our knowledge, to report on the synergistic apoptosis-inducing effects of aspirin and ISMN in human colon cancer cells, which were mediated via Wnt and NO signaling pathways. The results of the present study will facilitate the development of future therapeutic strategies. PMID:26094902

  2. Combining BET and HDAC inhibitors synergistically induces apoptosis of melanoma and suppresses AKT and YAP signaling

    PubMed Central

    Heinemann, Anja; Cullinane, Carleen; De Paoli-Iseppi, Ricardo; Wilmott, James S.; Gunatilake, Dilini; Madore, Jason; Strbenac, Dario; Yang, Jean Y.; Gowrishankar, Kavitha; Tiffen, Jessamy C.; Prinjha, Rab K.; Smithers, Nicholas; McArthur, Grant A.; Hersey, Peter; Gallagher, Stuart J.

    2015-01-01

    Histone acetylation marks have an important role in controlling gene expression and are removed by histone deacetylases (HDACs). These marks are read by bromodomain and extra-terminal (BET) proteins and novel inhibitiors of these proteins are currently in clinical development. Inhibitors of HDAC and BET proteins have individually been shown to cause apoptosis and reduce growth of melanoma cells. Here we show that combining the HDAC inhibitor LBH589 and BET inhibitor I-BET151 synergistically induce apoptosis of melanoma cells but not of melanocytes. Induction of apoptosis proceeded through the mitochondrial pathway, was caspase dependent and involved upregulation of the BH3 pro-apoptotic protein BIM. Analysis of signal pathways in melanoma cell lines resistant to BRAF inhibitors revealed that treatment with the combination strongly downregulated anti-apoptotic proteins and proteins in the AKT and Hippo/YAP signaling pathways. Xenograft studies showed that the combination of inhibitors was more effective than single drug treatment and confirmed upregulation of BIM and downregulation of XIAP as seen in vitro. These results support the combination of these two classes of epigenetic regulators in treatment of melanoma including those resistant to BRAF inhibitors. PMID:26087189

  3. Combination of ascorbate/epigallocatechin-3-gallate/gemcitabine synergistically induces cell cycle deregulation and apoptosis in mesothelioma cells

    SciTech Connect

    Martinotti, Simona; Ranzato, Elia; Parodi, Monica; Vitale, Massimo; Burlando, Bruno

    2014-01-01

    Malignant mesothelioma (MMe) is a poor-prognosis tumor in need of innovative therapies. In a previous in vivo study, we showed synergistic anti-MMe properties of the ascorbate/epigallocatechin-3-gallate/gemcitabine combination. We have now focused on the mechanism of action, showing the induction of apoptosis and cell cycle arrest through measurements of caspase 3, intracellular Ca{sup 2+}, annexin V, and DNA content. StellArray™ PCR technology and Western immunoblotting revealed DAPK2-dependent apoptosis, upregulation of cell cycle promoters, downregulation of cell cycle checkpoints and repression of NFκB expression. The complex of data indicates that the mixture is synergistic in inducing cell cycle deregulation and non-inflammatory apoptosis, suggesting its possible use in MMe treatment. - Highlights: • Ascorbate/epigallocathechin-gallate/gemcitabine has been tested on mesothelioma cells • A synergistic mechanism has been shown for cell cycle arrest and apoptosis • PCR-array analysis has revealed the de-regulation of apoptosis and cell cycle genes • Maximum upregulation has been found for the Death-Associated Protein Kinase-2 gene • Data suggest that the mixture could be used as a clinical treatment.

  4. [Honokiol combined with Gemcitabine synergistically inhibits the proliferation of human Burkitt lymphoma cells and induces their apoptosis].

    PubMed

    Zhang, Ming-Wan; Xu, Xiao-Jun; Fan, Jia-Xin; Hung, Yu-Xian; Ye, Yong-Bin; Wang, Jing; Guo, Kun-Yuan

    2014-02-01

    This study was aimed to investigate the effect of Honokiol (HNK) combined with Gemcitabine (GEM) on the proliferation and apoptosis of human Burkitt lymphoma Raji cells. Cell proliferation was detected by CCK-8 method to study the role of Honokiol and Gemcitabine in Raji cells. The cell apoptosis and cell cycle status were analyzed by flow cytometry. The level of apoptosis-related protein BCL-2 was measured with Western blot. The results showed that compared with cells treated with mentioned above drugs alone, the proliferative potential of cells in combination group was significantly inhibited (P < 0.01) and the inhibition rate was related to the concentration and action time of HNK; and apoptosis rate markedly increased (P < 0.01), while most Raji cells were arrested at G0/G1 phase and decreased in S phase after treatment with combination of two drugs; the expression of BCL-2 protein decreased (P < 0.01). It is concluded that Honokiol combined Gemcitabine can synergistically inhibit the proliferation, induce cell apoptosis, and down-regulate the expression of BCL-2 in Raji cells. The possible mechanism of synergistic effect may be related with arrest of cell cycle at G0/G1 phase and downregulation of the expression of BCL-2. PMID:24598658

  5. Synergistic Apoptosis-Inducing Effects on A375 Human Melanoma Cells of Natural Borneol and Curcumin

    PubMed Central

    Chen, Jianping; Li, Lin; Su, Jianyu; Li, Bing; Chen, Tianfeng; Wong, Yum-Shing

    2014-01-01

    This study was to investigate the synergistic effect of NB/Cur on growth and apoptosis in A375 human melanoma cell line by MTT assay, flow cytometry and Western blotting. Our results demonstrated that NB effectively synergized with Cur to enhance its antiproliferative activity on A375 human melanoma cells by induction of apoptosis, as evidenced by an increase in sub-G1 cell population, DNA fragmentation, PARP cleavage and caspase activation. Further mechanistic studies by Western blotting showed that after treatment of the cells with NB/Cur, up-regulation of the expression level of phosphorylated JNK and down-regulation of the expression level of phosphorylated ERK and Akt contributed to A375 cells apoptosis. Moreover, NB also potentiated Cur to trigger intracellular ROS overproduction and the DNA damage with up-regulation of the expression level of phosphorylated ATM, phosphorylated Brca1 and phosphorylated p53. The results indicate the combinational application potential of NB and Cur in treatments of cancers. PMID:24971451

  6. Benzo(a)pyrene Induced p53 Mediated Male Germ Cell Apoptosis: Synergistic Protective Effects of Curcumin and Resveratrol

    PubMed Central

    Banerjee, Bhaswati; Chakraborty, Supriya; Ghosh, Debidas; Raha, Sanghamitra; Sen, Parimal C.; Jana, Kuladip

    2016-01-01

    Benzo(a)pyrene (B(a)P) is an environmental toxicant that induces male germ cell apoptosis. Curcumin and resveratrol are phytochemicals with cytoprotective and anti-oxidative properties. At the same time resveratrol is also a natural Aryl hydrocarbon Receptor (AhR) antagonist. Our present study in isolated testicular germ cell population from adult male Wistar rats, highlighted the synergistic protective effect of curcumin and resveratrol against B(a)P induced p53 mediated germ cell apoptosis. Curcumin-resveratrol significantly prevented B(a)P induced decrease in sperm cell count and motility, as well as increased serum testosterone level. Curcumin-resveratrol co-treatment actively protected B(a)P induced testicular germ cell apoptosis. Curcumin-resveratrol co-treatment decreased the expression of pro-apoptotic proteins like cleaved caspase 3, 8 and 9, cleaved PARP, Apaf1, FasL, tBid. Curcumin-resveratrol co-treatment decreased Bax/Bcl2 ratio, mitochondria to cytosolic translocation of cytochrome c and activated the survival protein Akt. Curcumin-resveratrol decreased the expression of p53 dependent apoptotic genes like Fas, FasL, Bax, Bcl2, and Apaf1. B(a)P induced testicular reactive oxygen species (ROS) generation and oxidative stress were significantly ameliorated with curcumin and resveratrol. Curcumin-resveratrol co-treatment prevented B(a)P induced nuclear translocation of AhR and CYP1A1 (Cytochrome P4501A1) expression. The combinatorial treatment significantly inhibited B(a)P induced ERK 1/2, p38 MAPK and JNK 1/2 activation. B(a)P treatment increased the expression of p53 and its phosphorylation (p53 ser 15). Curcumin-resveratrol co-treatment significantly decreased p53 level and its phosphorylation (p53 ser 15). The study concludes that curcumin-resveratrol synergistically modulated MAPKs and p53, prevented oxidative stress, regulated the expression of pro and anti-apoptotic proteins as well as the proteins involved in B(a)P metabolism thus protected germ

  7. Benzo(a)pyrene Induced p53 Mediated Male Germ Cell Apoptosis: Synergistic Protective Effects of Curcumin and Resveratrol.

    PubMed

    Banerjee, Bhaswati; Chakraborty, Supriya; Ghosh, Debidas; Raha, Sanghamitra; Sen, Parimal C; Jana, Kuladip

    2016-01-01

    Benzo(a)pyrene (B(a)P) is an environmental toxicant that induces male germ cell apoptosis. Curcumin and resveratrol are phytochemicals with cytoprotective and anti-oxidative properties. At the same time resveratrol is also a natural Aryl hydrocarbon Receptor (AhR) antagonist. Our present study in isolated testicular germ cell population from adult male Wistar rats, highlighted the synergistic protective effect of curcumin and resveratrol against B(a)P induced p53 mediated germ cell apoptosis. Curcumin-resveratrol significantly prevented B(a)P induced decrease in sperm cell count and motility, as well as increased serum testosterone level. Curcumin-resveratrol co-treatment actively protected B(a)P induced testicular germ cell apoptosis. Curcumin-resveratrol co-treatment decreased the expression of pro-apoptotic proteins like cleaved caspase 3, 8 and 9, cleaved PARP, Apaf1, FasL, tBid. Curcumin-resveratrol co-treatment decreased Bax/Bcl2 ratio, mitochondria to cytosolic translocation of cytochrome c and activated the survival protein Akt. Curcumin-resveratrol decreased the expression of p53 dependent apoptotic genes like Fas, FasL, Bax, Bcl2, and Apaf1. B(a)P induced testicular reactive oxygen species (ROS) generation and oxidative stress were significantly ameliorated with curcumin and resveratrol. Curcumin-resveratrol co-treatment prevented B(a)P induced nuclear translocation of AhR and CYP1A1 (Cytochrome P4501A1) expression. The combinatorial treatment significantly inhibited B(a)P induced ERK 1/2, p38 MAPK and JNK 1/2 activation. B(a)P treatment increased the expression of p53 and its phosphorylation (p53 ser 15). Curcumin-resveratrol co-treatment significantly decreased p53 level and its phosphorylation (p53 ser 15). The study concludes that curcumin-resveratrol synergistically modulated MAPKs and p53, prevented oxidative stress, regulated the expression of pro and anti-apoptotic proteins as well as the proteins involved in B(a)P metabolism thus protected germ

  8. Synergistic effect of ERK inhibition on tetrandrine-induced apoptosis in A549 human lung carcinoma cells.

    PubMed

    Cho, Hyun Sun; Chang, Seung Hee; Chung, Youn Sun; Shin, Ji Young; Park, Sung Jin; Lee, Eun Sun; Hwang, Soon Kyung; Kwon, Jung Taek; Tehrani, Arash Minai; Woo, Minah; Noh, Mi Sook; Hanifah, Huda; Jin, Hua; Xu, Cheng Xiong; Cho, Myung Haing

    2009-03-01

    Tetrandrine (TET), a bis-benzylisoquinoline alkaloid from the root of Stephania tetrandra, is known to have anti-tumor activity in various malignant neoplasms. However, the precise mechanism by which TET inhibits tumor cell growth remains to be elucidated. The present studies were performed to characterize the potential effects of TET on phosphoinositide 3-kinase/Akt and extracellular signal-regulated kinase (ERK) pathways since these signaling pathways are known to be responsible for cell growth and survival. TET suppressed cell proliferation and induced apoptosis in A549 human lung carcinoma cells. TET treatment resulted in a down-regulation of Akt and ERK phosphorylation in both time-/concentration-dependent manners. The inhibition of ERK using PD98059 synergistically enhanced the TET-induced apoptosis of A549 cells whereas the inhibition of Akt using LY294002 had a less significant effect. Taken together, our results suggest that TET: i) selectively inhibits the proliferation of lung cancer cells by blocking Akt activation and ii) increases apoptosis by inhibiting ERK. The treatment of lung cancers with TET may enhance the efficacy of chemotherapy and radiotherapy and increase the apoptotic potential of lung cancer cells. PMID:19255520

  9. Magnetic nanoparticle of Fe3O4 and 5-bromotetrandrin interact synergistically to induce apoptosis by daunorubicin in leukemia cells

    PubMed Central

    Chen, Baoan; Cheng, Jian; Shen, Mingfang; Gao, Feng; Xu, Wenlin; Shen, Huilin; Ding, Jiahua; Gao, Chong; Sun, Qian; Sun, Xinchen; Cheng, Hongyan; Li, Guohong; Chen, Wenji; Chen, Ningna; Liu, Lijie; Li, Xiaomao; Wang, Xuemei

    2009-01-01

    Apoptosis is a common pathway that finally mediated the killing functions of anticancer drugs, which is an important cause of multidrug resistance (MDR). The aim of this study was to investigate the potential benefit of combination therapy with magnetic nanoparticle of Fe3O4 (MNP(Fe3O4)) and 5-bromotetrandrin (BrTet). Analysis of the apoptosis percentage showed that combination of daunorubicin (DNR) with either MNP(Fe3O4) or BrTet exerted a potent cytotoxic effect on K562/A02 cells, while MNP(Fe3O4) and BrTet cotreatment can synergistically enhance DNR-induced apoptosis. Importantly, we confirmed that the distinct synergism effect of that composite on reverse multidrug resistance may owe to the regulation of various proliferative and antiapoptotic gene products, including P53 and caspase-3. Thus our in vitro data strongly suggests a potential clinical application of MNP(Fe3O4) and BrTet combination on CML. PMID:19421371

  10. Synthetic retinoid CD437 induces apoptosis and acts synergistically with TRAIL receptor-2 agonist in malignant melanoma.

    PubMed

    Magnussen, Gry Irene; Ree Rosnes, Anne Katrine; Shahzidi, Susan; Dong, Hiep Phuc; Emilsen, Elisabeth; Engesæter, Birgit; Flørenes, Vivi Ann

    2012-04-13

    The novel synthetic retinoid, CD437, shows potent anti-tumor activity in a range of different cancer cell lines and now serves as a prototype for development of new retinoid related molecules (RRMs). The purpose of this study was to examine the effect and cellular targets of CD437 in the human metastatic melanoma cell lines FEMX-1 and WM239. We showed that treatment with CD437 led to cell cycle arrest and induced apoptosis through both the extrinsic- and intrinsic pathways (caspase 8, -9 and PARP cleavage) in both cell lines. Interestingly, apoptosis was induced independently of DNA-fragmentation in FEMX-1 cells, and appeared partially caspase-independent in the WM239 cells. Additionally, up-regulation of CHOP mRNA and cathepsin D protein expression, following retinoid treatment, suggests involvement of the endoplasmatic reticulum (ER) and lysosomes, respectively. Combination of suboptimal concentrations of CD437 and lexatumumab, a TRAIL death receptor-2 agonist, resulted in synergistic reduction of viable cells, along with increased PARP cleavage. These results indicate that CD437 has a strong anti-neoplastic effect alone and in combination with lexatumumab in melanoma cell lines. PMID:22446330

  11. Calcitriol and 20(S)-protopanaxadiol synergistically inhibit growth and induce apoptosis in human prostate cancer cells.

    PubMed

    Ben-Eltriki, Mohamed; Deb, Subrata; Adomat, Hans; Tomlinson Guns, Emma S

    2016-04-01

    The potential cancer preventive roles of calcitriol, the dihydroxylated metabolite of Vitamin D3, as well as 20(S)-protopanaxadiol (aPPD), the aglycone of the protopanaxadiol family of ginsenosides, have gained much attention in recent years for the prevention/treatment of prostate cancer (PCa). In the present study, we evaluated the anticancer and chemosensitization effects of calcitriol at clinically relevant concentrations and aPPD, either alone or in combination, in two well-characterized human PCa cell lines: androgen-sensitive non-metastatic LNCaP cells and androgen-independent metastatic C4-2 cells. The effects of the treatments on PCa cell viability and proliferation rates were evaluated by MTS and Brdu assays, respectively. Combination Indices (CI) and Dose Reduction Indices (DRI) were estimated to assess synergistic anticancer activity using Calcusyn software (Biosoft, Cambridge, UK). Then, we determined the potential Pharmacodynamic interaction mechanisms as follows: The protein expression levels of the genes those are known to control cell cycle (cyclin D1 and cdk2); apoptosis (Bcl-2, Bax, and Capspases 3), androgen receptor and Vitamin D receptors were examined upon combinational treatment. The cell viability assay data show that addition of 10nM calcitriol to aPPD significantly lowered its IC50 values from the range of 41-53μM to 13-23μM, in LNCaP and C4-2 prostate cancer cells. The cell proliferation rate was significantly lower for combination treatments compared to the cells treated with aPPD alone. Similarly, Western blot results indicate that aPPD significantly upregulated Vitamin D receptor (VDR) expression, while calcitriol further enhanced the ability of aPPD to induce pro-apoptotic BAX, increased cleaved caspase-3 and downregulate cdk2 protein levels. Thus, the pharmacodynamic interaction between aPPD and calcitriol in impacting growth inhibition and apoptosis appears to be synergistic in nature. In conclusion, calcitriol sensitizes PCa

  12. Synergistic Effect of the Flavonoid Catechin, Quercetin, or Epigallocatechin Gallate with Fluconazole Induces Apoptosis in Candida tropicalis Resistant to Fluconazole

    PubMed Central

    da Silva, Cecília Rocha; de Andrade Neto, João Batista; de Sousa Campos, Rosana; Figueiredo, Narjara Silvestre; Sampaio, Letícia Serpa; Magalhães, Hemerson Iury Ferreira; Cavalcanti, Bruno Coêlho; Gaspar, Danielle Macêdo; de Andrade, Geanne Matos; Lima, Iri Sandro Pampolha; de Barros Viana, Glauce Socorro; de Moraes, Manoel Odorico; Lobo, Marina Duarte Pinto; Grangeiro, Thalles Barbosa

    2014-01-01

    Flavonoids are a class of phenolic compounds commonly found in fruits, vegetables, grains, flowers, tea, and wine. They differ in their chemical structures and characteristics. Such compounds show various biological functions and have antioxidant, antimicrobial, anti-inflammatory, and antiapoptotic properties. The aim of this study was to evaluate the in vitro interactions of flavonoids with fluconazole against Candida tropicalis strains resistant to fluconazole, investigating the mechanism of synergism. Three combinations formed by the flavonoids (+)-catechin hydrated, hydrated quercetin, and (−)-epigallocatechin gallate at a fixed concentration with fluconazole were tested. Flavonoids alone had no antifungal activity within the concentration range tested, but when they were used as a cotreatment with fluconazole, there was significant synergistic activity. From this result, we set out to evaluate the possible mechanisms of cell death involved in this synergism. Isolated flavonoids did not induce morphological changes or changes in membrane integrity in the strains tested, but when they were used as a cotreatment with fluconazole, these changes were quite significant. When evaluating mitochondrial damage and the production of reactive oxygen species (ROS) only in the cotreatment, changes were observed. Flavonoids combined with fluconazole were shown to cause a significant increase in the rate of damage and the frequency of DNA damage in the tested strains. The cotreatment also induced an increase in the externalization of phosphatidylserine, an important marker of early apoptosis. It is concluded that flavonoids, when combined with fluconazole, show activity against strains of C. tropicalis resistant to fluconazole, promoting apoptosis by exposure of phosphatidylserine in the plasma membrane and morphological changes, mitochondrial depolarization, intracellular accumulation of ROS, condensation, and DNA fragmentation. PMID:24366745

  13. Magnetic Fe₃O₄ nanoparticles and chemotherapy agents interact synergistically to induce apoptosis in lymphoma cells.

    PubMed

    Jing, Hongmei; Wang, Jing; Yang, Ping; Ke, Xiaoyan; Xia, Guohua; Chen, Baoan

    2010-01-01

    The purpose of this study was to investigate the potential effects of combination therapy using magnetic nanoparticles of Fe₃O₄ (MNP-Fe₃O₄) and chemotherapeutic drugs on lymphoma cells. Proliferation, inhibition, and viability of Raji cells were detected by MTT and trypan blue exclusion. The percentage of cells undergoing apoptosis was detected by flow cytometry using fluorescein isothiocyanate-annexin V and propidium iodide staining. p53 and nuclear factor-κB (NF-κB) protein levels were measured by Western blot. The results showed that proliferation of Raji cells was inhibited by adriamycin or daunorubicin in a dose-and time-dependent manner. Cell sensitivity was improved and the 50% inhibitory concentrations of adriamycin and daunorubicin decreased when combined with a MNP-Fe₃O₄ carrier. Interestingly, increased apoptosis in Raji lymphoma cells was accompanied by upregulation of p53 protein and downregulation of NF-κB protein. Furthermore, the combination of MNP-Fe₃O₄ with adriamycin or daunorubicin increased p53 protein levels and decreased NF-κB protein levels more than adriamycin or daunorubicin alone, indicating that MNP-Fe₃O₄ could enhance the effect of chemotherapeutic drugs on p53 and NF-κB. Similar results for cell apoptosis and protein expression were not observed for the groups treated with dexamethasone ± MNP-Fe₃O₄ (P > 0.05). These findings suggest a potential clinical application for MNP-Fe₃O₄ in combination with daunorubicin or adriamycin in the treatment of lymphoma. PMID:21187919

  14. Novel histone deacetylase inhibitor MPT0G009 induces cell apoptosis and synergistic anticancer activity with tumor necrosis factor-related apoptosis-inducing ligand against human hepatocellular carcinoma

    PubMed Central

    Lai, Chin-Yu; Lin, Yi-Jyun; Liou, Jing-Ping; Lai, Mei-Jung; Li, Yu-Hsuan; Teng, Che-Ming; Yang, Chia-Ron

    2016-01-01

    Hepatocellular carcinoma (HCC) is a frequent cause of cancer-related death; therefore, more effective anticancer therapies for the treatment of HCC are needed. Histone deacetylase (HDAC) inhibitors serve as promising anticancer drugs because they can induce cell growth arrest and apoptosis. We previously reported that 3-[1-(4-methoxybenzenesulfonyl)-2,3-dihydro-1H-indol-5-yl]-N-hydroxyacrylamide (MPT0G009)—a novel 1-arylsulfonyl-5-(N-hydroxyacrylamide)indolines compound—demonstrated potent pan-HDAC inhibition and anti-inflammatory effects. In this study, we evaluated the anti-HCC activity of MPT0G009 in vitro and in vivo. Growth inhibition, apoptosis, and inhibited HDAC activity induced by MPT0G009 were more potent than a marketed HDAC inhibitor SAHA (Vorinostat). Furthermore, MPT0G009-induced apoptosis of Hep3B cells was characterized by an increase in apoptotic (sub-G1) population, loss of mitochondrial membrane potential, activation of caspase cascade, increased levels of pro-apoptotic protein (Bim), and decreased levels of anti-apoptotic proteins (Bcl-2, Bcl-xL, and FLICE-inhibitory protein); the downregulation FLIP by MPT0G009 is mediated through proteasome-mediated degradation and transcriptional suppression. In addition, combinations of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) with lower concentrations (0.1 μM) of MPT0G009 were synergistic in cell growth inhibition and apoptosis in HCC cells. In the in vivo model, MPT0G009 markedly reduced Hep3B xenograft tumor volume, inhibited HDAC activities, and induced apoptosis in the Hep3B xenografts. Our results demonstrate that MPT0G009 is a potential new candidate drug for HCC therapy. PMID:26587975

  15. Novel histone deacetylase inhibitor MPT0G009 induces cell apoptosis and synergistic anticancer activity with tumor necrosis factor-related apoptosis-inducing ligand against human hepatocellular carcinoma.

    PubMed

    Chen, Mei-Chuan; Huang, Hui-Hsuan; Lai, Chin-Yu; Lin, Yi-Jyun; Liou, Jing-Ping; Lai, Mei-Jung; Li, Yu-Hsuan; Teng, Che-Ming; Yang, Chia-Ron

    2016-01-01

    Hepatocellular carcinoma (HCC) is a frequent cause of cancer-related death; therefore, more effective anticancer therapies for the treatment of HCC are needed. Histone deacetylase (HDAC) inhibitors serve as promising anticancer drugs because they can induce cell growth arrest and apoptosis. We previously reported that 3-[1-(4-methoxybenzenesulfonyl)-2,3-dihydro-1H-indol-5-yl]-N-hydroxyacrylamide (MPT0G009)-a novel 1-arylsulfonyl-5-(N-hydroxyacrylamide)indolines compound-demonstrated potent pan-HDAC inhibition and anti-inflammatory effects. In this study, we evaluated the anti-HCC activity of MPT0G009 in vitro and in vivo. Growth inhibition, apoptosis, and inhibited HDAC activity induced by MPT0G009 were more potent than a marketed HDAC inhibitor SAHA (Vorinostat). Furthermore, MPT0G009-induced apoptosis of Hep3B cells was characterized by an increase in apoptotic (sub-G1) population, loss of mitochondrial membrane potential, activation of caspase cascade, increased levels of pro-apoptotic protein (Bim), and decreased levels of anti-apoptotic proteins (Bcl-2, Bcl-xL, and FLICE-inhibitory protein); the downregulation FLIP by MPT0G009 is mediated through proteasome-mediated degradation and transcriptional suppression. In addition, combinations of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) with lower concentrations (0.1 μM) of MPT0G009 were synergistic in cell growth inhibition and apoptosis in HCC cells. In the in vivo model, MPT0G009 markedly reduced Hep3B xenograft tumor volume, inhibited HDAC activities, and induced apoptosis in the Hep3B xenografts. Our results demonstrate that MPT0G009 is a potential new candidate drug for HCC therapy. PMID:26587975

  16. PCI-24781 (abexinostat), a novel histone deacetylase inhibitor, induces reactive oxygen species-dependent apoptosis and is synergistic with bortezomib in neuroblastoma

    PubMed Central

    Sholler, Giselle Saulnier; Currier, Erika A.; Dutta, Akshita; Slavik, Marni A.; Illenye, Sharon A.; Mendonca, Maria Cecilia F.; Dragon, Julie; Roberts, Stephen S.; Bond, Jeffrey P.

    2014-01-01

    In this study, we investigated the cytotoxic effects of a broad-spectrum histone deacetylase (HDAC) inhibitor, PCI-24781, alone and in combination with the proteasome inhibitor bortezomib in neuroblastoma cell lines. The combination was shown to induce synergistic cytotoxity involving the formation of reactive oxygen species. The cleavage of caspase-3 and PARP, as determined by western blotting, indicated that cell death was primarily due to apoptosis. Xenograft mouse models indicated increased survival among animals treated with this combination. The Notch signaling pathway and MYCN gene expression were quantified by reverse transcription-polymerase chain reaction (PCR) in cells treated with PCI-24781 and bortezomib, alone and in combination. Notch pathway expression increased in response to an HDAC inhibitor. NFKB1 and MYCN were both significantly down regulated. Our results suggest that PCI-24781 and bortezomib are synergistic in neuroblastoma cell lines and may be a new therapeutic strategy for this disease. PMID:25520806

  17. Bortezomib and SAHA synergistically induce ROS-driven caspase-dependent apoptosis of nasopharyngeal carcinoma and block replication of Epstein-Barr virus.

    PubMed

    Hui, Kwai Fung; Lam, Benjamin H W; Ho, Dona N; Tsao, Sai Wah; Chiang, Alan K S

    2013-05-01

    A novel drug combination of a proteasome inhibitor, bortezomib, and a histone deacetylase inhibitor, suberoylanilide hydroxamic acid (SAHA), was tested in nasopharyngeal carcinoma (NPC), both in vitro and in vivo. Dose-response of different concentrations of bortezomib and SAHA on inhibition of cell proliferation of NPC was determined. Mechanisms of apoptosis and effects on lytic cycle activation of Epstein-Barr virus (EBV) were investigated. Combination of bortezomib and SAHA (bortezomib/SAHA) synergistically induced killing of a panel of NPC cell lines. Pronounced increase in sub-G1, Annexin V-positive, and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL)-positive cell populations were detected after treatment with bortezomib/SAHA when compared with either drug alone. Concomitantly, markedly augmented proteolytic cleavage of PARP, caspase-3, -7, -8, and -9, reactive oxygen species (ROS) generation, and caspase-8-dependent histone acetylation were observed. ROS scavenger, N-acetyl cysteine, diminished the apoptotic effects of bortezomib/SAHA, whereas caspase inhibitor Z-VAD-FMK significantly suppressed the apoptosis without decreasing the generation of ROS. Bortezomib inhibited SAHA's induction of EBV replication and abrogated production of infectious viral particles in NPC cells. Furthermore, bortezomib/SAHA potently induced apoptosis and suppressed the growth of NPC xenografts in nude mice. In conclusion, the novel drug combination of bortezomib and SAHA is highly synergistic in the killing of NPC cells in vitro and in vivo. The major mechanism of cell death is ROS-driven caspase-dependent apoptosis. Bortezomib antagonizes SAHA's activation of EBV lytic cycle in NPC cells. This study provides a strong basis for clinical testing of the combination drug regimen in patients with NPC. PMID:23475956

  18. Gambogic acid synergistically potentiates cisplatin-induced apoptosis in non-small-cell lung cancer through suppressing NF-κB and MAPK/HO-1 signalling

    PubMed Central

    Wang, L-H; Li, Y; Yang, S-N; Wang, F-Y; Hou, Y; Cui, W; Chen, K; Cao, Q; Wang, S; Zhang, T-Y; Wang, Z-Z; Xiao, W; Yang, J-Y; Wu, C-F

    2014-01-01

    Background: Gambogic acid (GA) has been reported to have potent anticancer activity and is authorised to be tested in phase II clinical trials for treatment of non-small-cell lung cancer (NSCLC). The present study aims to investigate whether GA would be synergistic with cisplatin (CDDP) against the NSCLC. Methods: 1-(4,5-Dimethylthiazol-2-yl)-3,5-diphenylformazan (MTT), combination index (CI) isobologram, western blot, quantitative PCR, flow cytometry, electrophoretic mobility shift assay, xenograft tumour models and terminal deoxynucleotide transferase-mediated dUTP nick-end labelling analysis were used in this study. Results: The cell viability results showed that sequential CDDP-GA treatment resulted in a strong synergistic action in A549, NCI-H460, and NCI-H1299 cell lines, whereas the reverse sequence and simultaneous treatments led to a slight synergistic or additive action. Increased sub-G1 phase cells and enhanced PARP cleavage demonstrated that the sequence of CDDP-GA treatment markedly increased apoptosis in comparison with other treatments. Furthermore, the sequential combination could enhance the activation of caspase-3, -8, and 9, increase the expression of Fas and Bax, and decrease the expression of Bcl-2, survivin and X-inhibitor of apoptosis protein (X-IAP) in A549 and NCI-H460 cell lines. In addition, increased apoptosis was correlated with enhanced reactive oxygen species generation. Importantly, it was found that, followed by CDDP treatment, GA could inhibit NF-κB and mitogen-activated protein kinase (MAPK)/heme oxygenase-1 (HO-1) signalling pathways, which have been validated to reduce ROS release and confer CDDP resistance. The roles of NF-κB and MAPK pathways were further confirmed by using specific inhibitors, which significantly increased ROS release and apoptosis induced by the sequential combination of CDDP and GA. Moreover, our results indicated that the combination of CDDP and GA exerted increased antitumour effects on A549 xenograft

  19. Nitidine chloride inhibits proliferation, induces apoptosis via the Akt pathway and exhibits a synergistic effect with doxorubicin in ovarian cancer cells.

    PubMed

    Ding, Feng; Liu, Tianfeng; Yu, Nina; Li, Shihong; Zhang, Xiaofei; Zheng, Guanghong; Lv, Chunming; Mou, Kai; Xu, Jia; Li, Bo; Wang, Surong; Song, Haibo

    2016-09-01

    Nitidine chloride (NC) exhibits anti-tumor properties in various types of tumor. However, to the best of our knowledge there is no previous evidence of NC involvement in the apoptosis or proliferation of ovarian cancer cells and the underlying molecular mechanisms. The present study aimed to investigate the influence of NC on the viability and apoptosis of ovarian cancer cells and the synergistic effect NC and doxorubicin (DOX) may have on ovarian cancer cells. The viability and proliferation of ovarian cancer cells were examined using a methyl thiazolyl tetrazolium assay and 3H-thymidine incorporation assay. The apoptotic rate of ovarian cancer cells was detected by flow cytometry. The expression of apoptosis‑associated proteins and Akt serine/threonine kinase 1 (Akt) were determined by western blot analysis following NC treatment. The inhibitory effect of NC on the proliferation of ovarian cancer cells was demonstrated in a time and dose‑dependent manner. The pro-apoptotic effect of NC on ovarian cancer cells was also observed. It was determined that NC significantly downregulated the protein expression levels of B‑cell CLL/lymphoma 2 (Bcl-2) and upregulated the expression of Bcl‑2‑associated X protein, p53, caspase‑3 and ‑9. NC suppressed Akt phosphorylation. Additionally, the present study demonstrated that the effect of NC on the proliferation and apoptosis of ovarian cancer cells was Akt‑dependent by using the phosphatidylinositol-4,5-bisphosphate 3-kinase/Akt signaling pathway inhibitor, LY294002. NC exhibited a synergistic inhibitory effect on the viability of ovarian cancer cells when combined with DOX. The current study demonstrated that NC inhibited the proliferation and induced the apoptosis of ovarian cancer cells via the Akt signaling pathway and highlighted its potential clinical application for the treatment of ovarian cancer. PMID:27485415

  20. Synergistic Induction of Apoptosis in Primary B-CLL Cells after Treatment with Recombinant Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand and Histone Deacetylase Inhibitors

    PubMed Central

    Norian, Lyse A.; Kucaba, Tamara A.; Earel, James K.; Knutson, Tina; vanOosten, Rebecca L.; Griffith, Thomas S.

    2009-01-01

    Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is currently being investigated as a therapeutic agent for a variety of malignancies, as it triggers apoptosis specifically in transformed cells. However, TRAIL use as a stand alone therapeutic is hampered by the fact that many primary tumor cells are resistant to TRAIL-mediated apoptosis. Here, we investigated the extent to which pretreatment of TRAIL-resistant primary B-cell chronic lymphocytic leukemia (B-CLL) cells with histone deacetylase inhibitors (HDACis) could render them susceptible to killing by TRAIL. We found that HDAC inhibition in B-CLL cells led to increased TRAIL receptor expression, increased caspase activation, decreased expression of antiapoptotic regulators such as Bcl-2, and ultimately, enhanced TRAIL-induced apoptosis. Importantly, untransformed peripheral blood mononuclear cells remained largely resistant to TRAIL, even in the presence of HDACis. These results suggest that combination therapies using HDAC inhibition and TRAIL could prove beneficial for the treatment of B-CLL. PMID:19547714

  1. Paclitaxel and beta-lapachone synergistically induce apoptosis in human retinoblastoma Y79 cells by downregulating the levels of phospho-Akt.

    PubMed

    D'Anneo, Antonella; Augello, Giuseppa; Santulli, Andrea; Giuliano, Michela; di Fiore, Riccardo; Messina, Concetta; Tesoriere, Giovanni; Vento, Renza

    2010-02-01

    Paclitaxel (PTX) and beta-lapachone (LPC) are naturally occurring compounds that have shown a large spectrum of anticancer activity. In this article we show for the first time that PTX/LPC combination induces potent synergistic apoptotic effects in human retinoblastoma Y79 cells. Combination of suboptimal doses of PTX (0.3 nM) and LPC (1.5 microM) caused biochemical and morphological signs of apoptosis at 48 h of treatment. These effects were accompanied by potent lowering in inhibitor of apoptosis proteins and by activation of Bid and caspases 3 and 6 with lamin B and PARP breakdown. PTX/LPC combination acted by favoring p53 stabilization through a lowering in p-Akt levels and in ps166-MDM2, the phosphorylated-MDM2 form that enters the nucleus and induces p53 export and degradation. Treatment with wortmannin or transfection with a dominant negative form of Akt anticipated at 24 h the effects induced by PTX/LPC, suggesting a protective role against apoptosis played by Akt in Y79 cells. In line with these results, we demonstrated that Y79 cells contain constitutively active Akt, which forms a cytosolic complex with p53 and MDM2 driving p53 degradation. PTX/LPC treatment induced a weakness of Akt-MDM2-p53 complex and increased nuclear p53 levels. Our results suggest that phospho-Akt lowering is at the root of the apoptotic action exerted by PTX/LPC combination and provide strong validation for a treatment approach that targets survival signals represented by phospho-Akt and inhibitor of apoptosis proteins. PMID:19918798

  2. Histone deacetylase inhibitor trichostatin A and proteasome inhibitor PS-341 synergistically induce apoptosis in pancreatic cancer cells

    SciTech Connect

    Bai Jirong . E-mail: jbai@bidmc.harvard.edu; Demirjian, Aram; Sui Jianhua; Marasco, Wayne; Callery, Mark P. . E-mail: mcallery@bidmc.harvard.ede

    2006-10-06

    Pancreatic cancer is a common and lethal malignancy. Pancreatic cancer cells overexpress multiple anti-apoptotic factors and death receptor decoys, and are strongly resistant to radiation and to 5-fluorouracil (5-FU)- or gemcitabine (Gem)-based chemotherapy regimens. We have found that low-dose proteasome inhibitor PS-341 and histone deacetylase inhibitor trichostatin A (TSA) synergistically induce cytotoxicity in a panel of eight diverse pancreatic cancer cell lines. Combining TSA with PS-341 effectively inactivated NF{kappa}B signaling, downregulated the predominant endogenous anti-apoptotic factor Bcl-XL overexpression, and disrupted MAP kinase pathway. The combined drug regimen effectively inflicted an average of 71.5% apoptotic cell death (55.2-80%) in diverse pancreatic cancer cell lines by activating the intrinsic apoptotic pathway. Conclusion: the TSA/PS-341 regimen may represent a potential novel therapeutic strategy for pancreatic cancer.

  3. Novel nitric oxide-releasing spirolactone-type diterpenoid derivatives with in vitro synergistic anticancer activity as apoptosis inducer.

    PubMed

    Li, Dahong; Han, Tong; Tian, Kangtao; Tang, Shuang; Xu, Shengtao; Hu, Xu; Wang, Lei; Li, Zhanlin; Hua, Huiming; Xu, Jinyi

    2016-09-01

    Herein, we reported the cytotoxicity, NO-releasing property, and apoptosis induced ability of two series of novel nitric oxide-releasing spirolactone-type diterpenoid derivatives (10a-f and 15a-f). All the title compounds were more potent than oridonin (7) and parent compound (9 or 14) against human tumor Bel-7402, K562, MGC-803 and CaEs-17 cells. SARs were concluded based on above data. Compound 15d exhibited the strongest antiproliferative activity with the IC50 of 0.86, 1.74, 1.16 and 3.75μM, respectively, and could produce high level (above 25μM) of NO at the time point of 60min. Further mechanism evaluation showed that 15d could induce S phase cell cycle arrest and apoptosis at low micromolar concentrations in Bel-7402 cells via mitochondria-related pathways. It was expected that the remarkable biological profile of the synthetic NO-releasing spirolactone-type diterpenoid analogs make them possible as promising candidates for the development of anticancer agents. PMID:27491707

  4. EGFR-Targeted Hybrid Plasmonic Magnetic Nanoparticles Synergistically Induce Autophagy and Apoptosis in Non-Small Cell Lung Cancer Cells

    PubMed Central

    Kuroda, Shinji; Scott, Ailing W.; Aaron, Jesse; Larson, Tim; Shanker, Manish; Correa, Arlene M.; Kondo, Seiji; Roth, Jack A.; Sokolov, Konstantin; Ramesh, Rajagopal

    2011-01-01

    Background The epidermal growth factor receptor (EGFR) is overexpressed in 80% of non-small cell lung cancer (NSCLC) and is associated with poor survival. In recent years, EGFR-targeted inhibitors have been tested in the clinic for NSCLC. Despite the emergence of novel therapeutics and their application in cancer therapy, the overall survival rate of lung cancer patients remains 15%. To develop more effective therapies for lung cancer we have combined the anti-EGFR antibody (Clone 225) as a molecular therapeutic with hybrid plasmonic magnetic nanoparticles (NP) and tested on non-small cell lung cancer (NSCLC) cells. Methodology/Principal Findings Cell viability was determined by trypan-blue assay. Cellular protein expression was determined by Western blotting. C225-NPs were detected by electron microscopy and confocal microscopy, and EGFR expression using immunocytochemistry. C225-NP exhibited a strong and selective antitumor effect on EGFR-expressing NSCLC cells by inhibiting EGFR-mediated signal transduction and induced autophagy and apoptosis in tumor cells. Optical images showed specificity of interactions between C225-NP and EGFR-expressing NSCLC cells. No binding of C225-NP was observed for EGFR-null NSCLC cells. C225-NP exhibited higher efficiency in induction of cell killing in comparison with the same amount of free C225 antibody in tumor cells with different levels of EGFR expression. Furthermore, in contrast to C225-NP, free C225 antibody did not induce autophagy in cells. However, the therapeutic efficacy of C225-NP gradually approached the level of free antibodies as the amount of C225 antibody conjugated per nanoparticle was decreased. Finally, attaching C225 to NP was important for producing the enhanced tumor cell killing as addition of mixture of free C225 and NP did not demonstrate the same degree of cell killing activity. Conclusions/Significance We demonstrated for the first time the molecular mechanism of C225-NP induced cytotoxic effects in

  5. Bortezomib and fenretinide induce synergistic cytotoxicity in mantle cell lymphoma through apoptosis, cell-cycle dysregulation, and IκBα kinase downregulation.

    PubMed

    Cowan, Andrew J; Frayo, Shani L; Press, Oliver W; Palanca-Wessels, Maria C; Pagel, John M; Green, Damian J; Gopal, Ajay K

    2015-10-01

    Mantle cell lymphoma (MCL) remains incurable for most patients, and proteasome inhibitors like bortezomib induce responses in a minority of patients with relapsed disease. Fenretinide is a retinoid that has shown preclinical activity in B-cell lymphomas. We hypothesized that these agents could yield augmented antitumor activity. MCL lines (Granta-519, Jeko-1, and Rec-1) were treated with escalating concentrations of bortezomib and fenretinide singly and in combination. Cytotoxicity was assessed using the MTT assay. Flow cytometric methods were used to assess apoptosis and necrosis, with annexin V-FITC/propidium iodide staining, and G1 and G2 cell-cycle changes were assessed by DAPI staining. Changes in cyclin D1, cyclin B, IκBα, and IKKα expressions were quantified by western blotting. Cytotoxicity was mediated through apoptosis; both agents showed observed versus expected cytotoxicities of 92.2 versus 55.1% in Granta-519, of 87.6 versus 36.3% in Jeko-1, and of 63.2 versus 29.8% in Rec-1. Isobolographic analysis confirmed synergy in Jeko-1 and Rec-1 cell lines. Bortezomib induced G2-phase arrest, with a 1.7-fold increase compared with control, and fenretinide resulted in G1-phase arrest, with an increase of 1.3-fold compared with control. In the combination, G2-phase arrest predominated, with a 1.4-fold increase compared with control, and there was reduced expression of cyclin D1 to 24%, cyclin B to 52 and 64%, cyclin D3 to 25 and 43%, IκBα to 23 and 46%, and IκBα kinase to 34 and 44%. Bortezomib and fenretinide exhibit synergistic cytotoxicity against MCL cell lines. This activity is mediated by IκBα kinase modulation, decreased cyclin expression, cell cycle dysregulation, and apoptotic cell death. PMID:26237500

  6. Chrysin, Abundant in Morinda citrifolia Fruit Water-EtOAc Extracts, Combined with Apigenin Synergistically Induced Apoptosis and Inhibited Migration in Human Breast and Liver Cancer Cells.

    PubMed

    Huang, Cheng; Wei, Yu-Xuan; Shen, Ma-Ching; Tu, Yu-Hsuan; Wang, Chia-Chi; Huang, Hsiu-Chen

    2016-06-01

    The composition of Morinda citrifolia (M. citrifolia) was determined using high-performance liquid chromatography (HPLC), and the anticancer effects of M. citrifolia extract evaluated in HepG2, Huh7, and MDA-MB-231 cancer cells. M. citrifolia fruit extracts were obtained by using five different organic solvents, including hexane (Hex), methanol (MeOH), ethyl acetate (EtOAc), chloroform (CHCl3), and ethanol (EtOH). The water-EtOAc extracts from M. citrifolia fruits was found to have the highest anticancer activity. HPLC data revealed the predominance of chrysin in water-EtOAc extracts of M. citrifolia fruit. Furthermore, the combined effects of cotreatment with apigenin and chrysin on liver and breast cancer were investigated. Treatment with apigenin plus chrysin for 72-96 h reduced HepG2 and MDA-MB-231 cell viability and induced apoptosis through down-regulation of S-phase kinase-associated protein-2 (Skp2) and low-density lipoprotein receptor-related protein 6 (LRP6) expression. However, the combination treatment for 36 h synergistically decreased MDA-MB-231 cell motility but not cell viability through down-regulation of MMP2, MMP9, fibronectin, and snail in MDA-MB-231 cells. Additionally, chrysin combined with apigenin also suppressed tumor growth in human MDA-MB-231 breast cancer cells xenograft through down-regulation of ki-67 and Skp2 protein. The experimental results showed that chrysin combined with apigenin can reduce HepG2 and MDA-MB-231 proliferation and cell motility and induce apoptosis. It also offers opportunities for exploring new drug targets, and further investigations are underway in this regard. PMID:27137679

  7. Auranofin induces apoptosis by ROS-mediated ER stress and mitochondrial dysfunction and displayed synergistic lethality with piperlongumine in gastric cancer

    PubMed Central

    Zou, Peng; Chen, Minxiao; Ji, Jiansong; Chen, Weiqian; Chen, Xi; Ying, Shilong; Zhang, Junru; Zhang, Ziheng; Liu, Zhiguo; Yang, Shulin; Liang, Guang

    2015-01-01

    Gastric cancer (GC) is one of the leading causes of cancer mortality in the world. In addressing the need of treatments for relapsed disease, we report the identification of an existing U.S. Food and Drug Administration-approved small-molecule drug to repurpose for GC treatment. Auranofin (AF), clinically used to treat rheumatic arthritis, but it exhibited preclinical efficacy in GC cells. By increasing intracellular reactive oxygen species (ROS) levels, AF induces a lethal endoplasmic reticulum stress response and mitochondrial dysfunction in cultured GC cells. Blockage of ROS production reversed AF-induced ER stress and mitochondrial pathways activation as well as apoptosis. In addition, AF displays synergistic lethality with an ROS-generating agent piperlongumine, which is a natural product isolated from the long pepper Piper longum L. Taken together, this work provides a novel anticancer candidate for the treatment of gastric cancer. More importantly, it reveals that increased ROS generation might be an effective strategy in treating human gastric cancer. PMID:26431378

  8. Auranofin induces apoptosis by ROS-mediated ER stress and mitochondrial dysfunction and displayed synergistic lethality with piperlongumine in gastric cancer.

    PubMed

    Zou, Peng; Chen, Minxiao; Ji, Jiansong; Chen, Weiqian; Chen, Xi; Ying, Shilong; Zhang, Junru; Zhang, Ziheng; Liu, Zhiguo; Yang, Shulin; Liang, Guang

    2015-11-01

    Gastric cancer (GC) is one of the leading causes of cancer mortality in the world. In addressing the need of treatments for relapsed disease, we report the identification of an existing U.S. Food and Drug Administration-approved small-molecule drug to repurpose for GC treatment. Auranofin (AF), clinically used to treat rheumatic arthritis, but it exhibited preclinical efficacy in GC cells. By increasing intracellular reactive oxygen species (ROS) levels, AF induces a lethal endoplasmic reticulum stress response and mitochondrial dysfunction in cultured GC cells. Blockage of ROS production reversed AF-induced ER stress and mitochondrial pathways activation as well as apoptosis. In addition, AF displays synergistic lethality with an ROS-generating agent piperlongumine, which is a natural product isolated from the long pepper Piper longum L. Taken together, this work provides a novel anticancer candidate for the treatment of gastric cancer. More importantly, it reveals that increased ROS generation might be an effective strategy in treating human gastric cancer. PMID:26431378

  9. Novel synergistic mechanism for sst2 somatostatin and TNFalpha receptors to induce apoptosis: crosstalk between NF-kappaB and JNK pathways.

    PubMed

    Guillermet-Guibert, J; Saint-Laurent, N; Davenne, L; Rochaix, P; Cuvillier, O; Culler, M D; Pradayrol, L; Buscail, L; Susini, C; Bousquet, C

    2007-02-01

    Somatostatin is a multifunctional hormone that modulates cell proliferation, differentiation and apoptosis. Mechanisms for somatostatin-induced apoptosis are at present mostly unsolved. Therefore, we investigated whether somatostatin receptor subtype 2 (sst2) induces apoptosis in the nontransformed murine fibroblastic NIH3T3 cells. Somatostatin receptor subtype 2 expression induced an executioner caspase-mediated apoptosis through a tyrosine phosphatase SHP-1 (Src homology domain phosphatase-1)-dependent stimulation of nuclear factor kappa B (NF-kappaB) activity and subsequent inhibition of the mitogen-activated protein kinase JNK. Tumor necrosis factor alpha (TNFalpha) stimulated both NF-kappaB and c-Jun NH2-terminal kinase (JNK) activities, which had opposite action on cell survival. Importantly, sst2 sensitized NIH3T3 cells to TNFalpha-induced apoptosis by (1) upregulating TNFalpha receptor protein expression, and sensitizing to TNFalpha-induced caspase-8 activation; (2) enhancing TNFalpha-mediated activation of NF-kappaB, resulting in JNK inhibition and subsequent executioner caspase activation and cell death. We have here unraveled a novel signaling mechanism for a G protein-coupled receptor, which directly triggers apoptosis and crosstalks with a death receptor to enhance death ligand-induced apoptosis. PMID:16645635

  10. Resveratrol and curcumin synergistically induces apoptosis in cigarette smoke condensate transformed breast epithelial cells through a p21(Waf1/Cip1) mediated inhibition of Hh-Gli signaling.

    PubMed

    Mohapatra, Purusottam; Satapathy, Shakti Ranjan; Siddharth, Sumit; Das, Dipon; Nayak, Anmada; Kundu, Chanakya Nath

    2015-09-01

    Combination therapy using two or more small molecule inhibitors of aberrant signaling cascade in aggressive breast cancers is a promising therapeutic strategy over traditional monotherapeutic approaches. Here, we have studied the synergistic mechanism of resveratrol and curcumin induced apoptosis using in vitro (cigarette smoke condensate mediated transformed breast epithelial cell, MCF-10A-Tr) and in vivo (tumor xenograft mice) model system. Resveratrol exposure increased the intracellular uptake of curcumin in a dose dependent manner and caused apoptosis in MCF-10A-Tr cells. Approximately, ten fold lower IC50 value was noted in cells treated with the combination of resveratrol (3μM) and curcumin (3μM) in comparison to 30μM of resveratrol or curcumin alone. Resveratrol+curcumin combination caused apoptosis by increasing Bax/Bcl-xL ratio, Cytochrome C release, cleaved product of PARP and caspase 3 in cells. Interestingly, this combination unaltered the protein expressions of WNT-TCF and Notch signaling components, β-catenin and cleaved notch-1 val1744, respectively. Furthermore, the combination also significantly decreased the intermediates of Hedgehog-Gli cascade including SMO, SHH, Gli-1, c-MYC, Cyclin-D1, etc. and increased the level of p21(Waf/Cip1) in vitro and in vivo. A significant reduction of Gli- promoter activity was noted in combinational drug treated cells in comparison to individual drug treatment. Un-alteration of the expressions of the above proteins and Gli1 promoter activity in p21(Waf/Cip1) knockout cells suggests this combination caused apoptosis through p21(Waf/Cip1). Thus, our findings revealed resveratrol and curcumin synergistically caused apoptosis in cigarette smoke induced breast cancer cells through p2(Waf/Cip1) mediated inhibition of Hedgehog-Gli cascade. PMID:26212257

  11. Cisplatin-induced apoptosis in non-small-cell lung cancer cells is dependent on Bax- and Bak-induction pathway and synergistically activated by BH3-mimetic ABT-263 in p53 wild-type and mutant cells.

    PubMed

    Matsumoto, Masaru; Nakajima, Wataru; Seike, Masahiro; Gemma, Akihiko; Tanaka, Nobuyuki

    2016-04-29

    Cisplatin is a highly effective anticancer drug for treatment of various tumors including non-small-cell lung cancer (NSCLC), and is especially useful in cases nonresponsive to molecular-targeted drugs. Accumulating evidence has shown that cisplatin activates the p53-dependent apoptotic pathway, but it also induces apoptosis in p53-mutated cancer cells. Here we demonstrated that DNA-damage inducible proapoptotic BH3 (Bcl-2 homology region 3)-only Bcl-2 family members, Noxa, Puma, Bim and Bid, are not involved in cisplatin-induced apoptosis in human NSCLC cell lines. In contrast, the expression of proapoptotic multidomain Bcl-2-family members, Bak and Bax, was induced by cisplatin in p53-dependent and -independent manners, respectively. Moreover, in wild-type p53-expressing cells, cisplatin mainly used the Bak-dependent apoptotic pathway, but this apoptotic pathway shifted to the Bax-dependent pathway by loss-of-function of p53. Furthermore, both Bak- and Bax-induced apoptosis was enhanced by the antiapoptotic Bcl-2 family member, Bcl-XL knockdown, but not by Mcl-1 knockdown. From this result, we tested the effect of ABT-263 (Navitoclax), the specific inhibitor of Bcl-2 and Bcl-XL, but not Mcl-1, and found that ABT-263 synergistically enhanced cisplatin-induced apoptosis in NSCLC cells in the presence or absence of p53. These results indicate a novel regulatory system in cisplatin-induced NSCLC cell apoptosis, and a candidate efficient combination chemotherapy method against lung cancers. PMID:26996126

  12. Rapamycin interacts synergistically with idarubicin to induce T-leukemia cell apoptosis in vitro and in a mesenchymal stem cell simulated drug-resistant microenvironment via Akt/mammalian target of rapamycin and extracellular signal-related kinase signaling pathways.

    PubMed

    Wu, Kang-Ni; Zhao, Yan-Min; He, Ying; Wang, Bin-Sheng; Du, Kai-Li; Fu, Shan; Hu, Kai-Min; Zhang, Li-Fei; Liu, Li-Zhen; Hu, Yong-Xian; Wang, Ying-Jia; Huang, He

    2014-03-01

    T-cell acute lymphoblastic leukemias (T-ALLs) are clonal lymphoid malignancies with a poor prognosis, and still a lack of effective treatment. Here we examined the interactions between the mammalian target of rapamycin (mTOR) inhibitor rapamycin and idarubicin (IDA) in a series of human T-ALL cell lines Molt-4, Jurkat, CCRF-CEM and CEM/C1. Co-exposure of cells to rapamycin and IDA synergistically induced T-ALL cell growth inhibition and apoptosis mediated by caspase activation via the intrinsic mitochondrial pathway and extrinsic pathway. Combined treatment with rapamycin and IDA down-regulated Bcl-2 and Mcl-1, and inhibited the activation of phosphoinositide 3-kinase (PI3K)/mTOR and extracellular signal-related kinase (ERK). They also played synergistic pro-apoptotic roles in the drug-resistant microenvironment simulated by mesenchymal stem cells (MSCs) as a feeder layer. In addition, MSCs protected T-ALL cells from IDA cytotoxicity by up-regulating ERK phosphorylation, while rapamycin efficiently reversed this protective effect. Taken together, we confirm the synergistic antitumor effects of rapamycin and IDA, and provide an insight into the potential future clinical applications of combined rapamycin-IDA regimens for treating T-cell malignancies. PMID:23741975

  13. Combination of 5-fluorouracil and genistein induces apoptosis synergistically in chemo-resistant cancer cells through the modulation of AMPK and COX-2 signaling pathways

    SciTech Connect

    Hwang, Jin-Taek; Ha, Joohun; Park, Ock Jin . E-mail: ojpark@hannam.ac.kr

    2005-07-01

    5-Fluorouracil (5-FU) is one of the widely used chemotherapeutic drugs targeting various cancers, but its chemo-resistance remains as a major obstacle in clinical settings. In the present study, HT-29 colon cancer cells were markedly sensitized to apoptosis by both 5-FU and genistein compared to the 5-FU treatment alone. There is an emerging evidence that genistein, soy-derived phytoestrogen, may have potential as a chemotherapeutic agent capable of inducing apoptosis or suppressing tumor promoting proteins such as cyclooxygenase-2 (COX-2). However, the precise mechanism of cellular cytotoxicity of genistein is not known. The present study focused on the correlation of AMPK and COX-2 in combined cytotoxicity of 5-FU and genistein, since AMPK is known as a primary cellular homeostasis regulator and a possible target molecule of cancer treatment, and COX-2 as cell proliferation and anti-apoptotic molecule. Our results demonstrated that the combination of 5-FU and genistein abolished the up-regulated state of COX-2 and prostaglandin secretion caused by 5-FU treatment in HT-29 colon cancer cells. These appear to be followed by the specific activation of AMPK and the up-regulation of p53, p21, and Bax by genistein. Under same conditions, the induction of Glut-1 by 5-FU was diminished by the combination treatment with 5-FU and genistein. Furthermore, the reactive oxygen species (ROS) was found as an upstream signal for AMPK activation by genistein. These results suggested that the combination of 5-FU and genistein exert a novel chemotherapeutic effect in colon cancers, and AMPK may be a novel regulatory molecule of COX-2 expression, further implying its involvement in cytotoxicity caused by genistein.

  14. Inhibition of hedgehog signaling by GANT58 induces apoptosis and shows synergistic antitumor activity with AKT inhibitor in acute T cell leukemia cells.

    PubMed

    Hou, Xiaoming; Chen, Xing; Zhang, Ping; Fan, Youfei; Ma, Aihua; Pang, Tingting; Song, Zhao; Jin, Youpeng; Hao, Wei; Liu, Fengqin; Wang, Wei; Wang, Yulin

    2014-06-01

    The hedgehog (Hh) signaling pathways have a crucial role in cell proliferation and survival, and the de-regulation of these pathways can lead to tumorigenesis. Here we investigated the expression and function of these pathways in acute T lymphocytic leukemia cells (T-ALL). Profiling of Hh pathway members revealed common expression of key Hh signaling effectors in all T-ALL cells. We found that T-ALL cells were insensitive to specific Smoothened (SMO) inhibition following the use of low concentrations of the SMO antagonist cyclopamine. In contrast, treatment with the novel GLI antagonist GANT58 reduced expression of the target gene Patched 1 as well as GLI family zinc finger 1 (GLI1) and preferentially decreased the viability of T-ALL cells. We also found perifosine, a novel AKT inhibitor, down-regulated GLI1 protein by dephosphorylation of AKT and GSK3β dose-dependently and that pre-treatment with PD98059, a MEK/ERK pathway inhibitor, enhanced this down-regulation by 20%-30%. Then we questioned whether use of both GANT58 and AKT inhibitor together could confer a synergistic effect to decrease T-ALL cell viability. By applying the Chou-Talalay method, low concentration of GANT58 induced T-ALL cell death in a synergism fashion with perifosine or GSK690693 when used simultaneously. These findings indicate that the combined use of GANT58 and AKT inhibitor could help treat a broad range of malignant tumors in conjunction with existing cancer treatments. PMID:24394624

  15. Concurrent targeting of EP1/EP4 receptors and COX-2 induces synergistic apoptosis in KSHV and EBV associated non-Hodgkin lymphoma cell lines

    PubMed Central

    Paul, Arun George; Chandran, Bala; Sharma-Walia, Neelam

    2014-01-01

    The effective anti-tumorigenic potential of non-steroidal anti-inflammatory drugs (NSAIDs) and eicosonoid (EP; EP1–4) receptor antagonists prompted us to test their efficacy in Kaposi's sarcoma-associated herpesvirus (KSHV) and Epstein-Barr virus (EBV) related lymphomas. Our study demonstrated that (1) EP1–4 receptor protein levels vary among the various non-Hodgkin’s lymphoma (NHL) cell lines tested (BCBL-1:KSHV+/EBV−;BC-3: KSHV+/EBV−; Akata/EBV+: KSHV−/EBV+; and JSC-1 cells: KSHV+/EBV+ cells); (2) 5.0 µM of EP1 antagonist (SC-51322) had a significant anti-proliferative effect on BCBL-1, BC-3, Akata/EBV+, and JSC-1 cells; (3) 50.0 µM of EP2 antagonist (AH6809) was required to induce a significant anti-proliferative effect on BCBL-1, Akata/EBV+, and JSC-1 cells; (4) 5.0 µM of EP4 antagonist (GW 627368X) had a significant anti-proliferative effect on BC-3, Akata/EBV+, and JSC-1 cells; (5) COX-2 selective inhibitor celecoxib (5.0µM) had significant anti-proliferative effects on BCBL-1, BC-3, Akata/EBV+, and JSC-1 cells; and (6) a combination of 1.0µM each of celecoxib, SC-51322 and GW 627368X could potentiate the pro-apoptotic properties of celecoxib or vice-versa. Overall, our studies identified the synergistic anti-proliferative effect of NSAIDs and EP receptor blockers on KSHV and EBV related B cell malignancies. PMID:23523954

  16. Synergistically combined gene delivery for enhanced VEGF secretion and anti-apoptosis

    PubMed Central

    Won, Young-Wook; Lee, Minhyung; Kim, Hyun Ah; Nam, Kihoon; Bull, David A.; Kim, Sung Wan

    2013-01-01

    With current pharmacological treatments, preventing the remodeling of the left ventricle and the progression to heart failure is a difficult task. Gene therapy is considered to provide a direct treatment to the long-term complications of ischemic heart diseases. Although current gene therapies that use single molecular targets seem potentially possible, they have not achieved a success in the treatment of ischemic diseases. With an efficient polymeric gene carrier, PAM-ABP, we designed a synergistically combined gene delivery strategy to enhance vascular endothelial growth factor (VEGF) secretion and prolong anti-apoptotic effects. A hypoxia-inducible plasmid expressing both hypoxia-inducible heme oxygenase-1 (HO-1) and the Src homology domain-2 containing tyrosine phosphatase-1 microRNA (miSHP 1) and a hypoxia-responsive VEGF plasmid were combined in this study. The positive feedback circuit between HO-1 and VEGF, and the negative regulatory role of SHP-1 in angiogenesis enhance VEGF secretion synergistically. The synergy in VEGF secretion as a consequence of the gene combination and the prolonged HO-1 activity was confirmed in hypoxic cardiomyocytes and cardiomyocyte apoptosis under hypoxia, and was decreased synergistically. These results suggest that the synergistic combination of VEGF, HO-1, and miSHP-1 may be promising for the clinical treatment of ischemic diseases. PMID:24007285

  17. Dual inhibition of MEK1/2 and EGFR synergistically induces caspase-3-dependent apoptosis in EGFR inhibitor-resistant lung cancer cells via BIM upregulation.

    PubMed

    Song, Ji-Young; Kim, Choung-Soo; Lee, Je-Hwan; Jang, Se Jin; Lee, Sang-wook; Hwang, Jung Jin; Lim, Chulsoo; Lee, Gilnam; Seo, Jeongbeob; Cho, Suk Young; Choi, Jene

    2013-12-01

    Epidermal growth factor receptor (EGFR) gene mutations activate the KRAS-RAF-MEK-ERK pathway in lung cancer cells. EGFR tyrosine kinase inhibitors (TKIs) such as gefitinib induce apoptosis of cancer cells, but prolonged treatment is often associated with acquired resistance. Here, we identified a novel MEK1/2 inhibitor, CZ0775, and compared its cytotoxic effects to those of AZD6244 (selumetinib) in non-small cell lung cancer (NSCLC) cell lines harboring EGFR mutations. The lapatinib-sensitive HCC827 and PC9 and lapatinib-resistant H1650 and H1975 cell lines showed poor responses to CZ0775 and AZD6244 monotherapy with an IC50 > 10 μM. By contrast, combination treatment with lapatinib and CZ0775 inhibited cell proliferation and produced a 2-fold higher number of annexin V-labeled cells than lapatinib alone in H1975 cells. Furthermore, combination treatment decreased phosphorylated extracellular signal related kinase (p-ERK) and survivin levels and upregulated the expression of the pro-apoptotic protein BIM. siRNA-mediated BIM depletion reduced caspase-3 activity (~40%) in lapatinib and CZ0775 treated H1975 cells. An in vitro ERK activity assay showed that p-ERK levels were approximately a 3-fold lower in H1975 cells treated with CZ0775 and lapatinib combination than in cells treated with lapatinib alone. CZ0775 was more cytotoxic than AZD6244 when used in combination with lapatinib. Our results suggest that combination treatment with CZ0774 and EGFR inhibitors is a promising therapeutic approach for the treatment of EGFR-TKI-resistant lung cancers and its effect is mediated by the inhibition of ERK and the induction of BIM. PMID:24068620

  18. Synergistic Effects Induced by a Low Dose of Diesel Particulate Extract and Ultraviolet-A in Caenorhabditis elegans: DNA Damage-Triggered Germ Cell Apoptosis

    PubMed Central

    2015-01-01

    Diesel exhaust has been classified as a potential carcinogen and is associated with various health effects. A previous study showed that the doses for manifesting the mutagenetic effects of diesel exhaust could be reduced when coexposed with ultraviolet-A (UVA) in a cellular system. However, the mechanisms underlying synergistic effects remain to be clarified, especially in an in vivo system. In the present study, using Caenorhabditis elegans (C. elegans) as an in vivo system we studied the synergistic effects of diesel particulate extract (DPE) plus UVA, and the underlying mechanisms were dissected genetically using related mutants. Our results demonstrated that though coexposure of wild type worms at young adult stage to low doses of DPE (20 μg/mL) plus UVA (0.2, 0.5, and 1.0 J/cm2) did not affect worm development (mitotic germ cells and brood size), it resulted in a significant induction of germ cell death. Using the strain of hus-1::gfp, distinct foci of HUS-1::GFP was observed in proliferating germ cells, indicating the DNA damage after worms were treated with DPE plus UVA. Moreover, the induction of germ cell death by DPE plus UVA was alleviated in single-gene loss-of-function mutations of core apoptotic, checkpoint HUS-1, CEP-1/p53, and MAPK dependent signaling pathways. Using a reactive oxygen species (ROS) probe, it was found that the production of ROS in worms coexposed to DPE plus UVA increased in a time-dependent manner. In addition, employing a singlet oxygen (1O2) trapping probe, 2,2,6,6-tetramethyl-4-piperidone, coupled with electron spin resonance analysis, we demonstrated the increased 1O2 production in worms coexposed to DPE plus UVA. These results indicated that UVA could enhance the apoptotic induction of DPE at low doses through a DNA damage-triggered pathway and that the production of ROS, especially 1O2, played a pivotal role in initiating the synergistic process. PMID:24841043

  19. Combined treatment with vitamin C and sulindac synergistically induces p53- and ROS-dependent apoptosis in human colon cancer cells.

    PubMed

    Gong, Eun-Yeung; Shin, Yu Jin; Hwang, Ih-Yeon; Kim, Jeong Hee; Kim, Seung-Mi; Moon, Jai-Hee; Shin, Jae-Sik; Lee, Dae-Hee; Hur, Dae Young; Jin, Dong-Hoon; Hong, Seung-Woo; Lee, Won Keun; Lee, Wang-Jae

    2016-09-01

    Sulindac has anti-neoplastic properties against colorectal cancers; however, its use as a chemopreventive agent has been limited due to toxicity and efficacy concerns. Combinatorial treatment of colorectal cancers has been attempted to maximize anti-cancer efficacy with minimal side effects by administrating NSAIDs in combination with other inhibitory compounds or drugs such as l-ascorbic acid (vitamin C), which is known to exhibit cytotoxicity towards various cancer cells at high concentrations. In this study, we evaluated a combinatorial strategy utilizing sulindac and vitamin C. The death of HCT116 cells upon combination therapy occurred via a p53-mediated mechanism. The combination therapeutic resistance developed in isogenic p53 null HCT116 cells and siRNA-mediated p53 knockdown HCT116 cells, but the exogenous expression of p53 in p53 null isogenic cells resulted in the induction of cell death. In addition, we investigated an increased level of intracellular ROS (reactive oxygen species), which was preceded by p53 activation. The expression level of PUMA (p53-upregulated modulator of apoptosis), but not Bim, was significantly increased in HCT116 cells in response to the combination treatment. Taken together, our results demonstrate that combination therapy with sulindac and vitamin C could be a novel anti-cancer therapeutic strategy for p53 wild type colon cancers. PMID:27339904

  20. Synergistic property of cordycepin in cultivated Cordyceps militaris-mediated apoptosis in human leukemia cells.

    PubMed

    Chou, Shang-Min; Lai, Wan-Jung; Hong, Tzu-Wen; Lai, Jui-Ya; Tsai, Sheng-Hong; Chen, Yen-Hsun; Yu, Sz-Hsien; Kao, Cheng-Hsiang; Chu, Richard; Ding, Shih-Torng; Li, Tsai-Kun; Shen, Tang-Long

    2014-10-15

    Cordyceps militaris is a well-known Chinese traditional medicinal mushroom frequently used for tonics and recently of a potential interest for cancer intervention. Here, we explored the cancer cell killing activity of the hot water extracts of C. militaris cultured mycelia (CM(MY)) and cultivated fruiting bodies (CM(FB)). We found that CM(FB) exhibited a greater cytotoxic effect against various cancer cells over CM(MY). Apoptotic phenotypes including apoptotic body formation, DNA laddering, caspase 3 activation and cleavage of PARP proteins were induced by CM(FB) treatment but only slightly induced by same concentration of CM(MY) treatment in human HL-60 leukemia cells. Cordycepin in CM(FB) (10.47 mg/g) is significantly higher (∼ 15.2 times) than that of CM(MY) (0.69 mg/g). Using isobolographic analysis, the synergy of cytotoxicity was observed across different combined concentrations of CM(MY) and cordycepin. By complementing cordycepin into CM(MY) to the level comparable with CM(FB), we observed that CM(MY) (500 μg/ml) with cordycepin (4.8 μg/ml) induced apoptosis to a level similar to that induced by CM(FB) (500 μg/ml). Together, our results suggest that cordycepin possesses a synergistic cytotoxic effect with Cordyceps militaris-mediated apoptosis in human leukemia cells and therefore explaining a better anti-proliferating activity of CM(FB) over CM(MY). PMID:25442260

  1. Synergistic anticancer effect of the extracts from Polyalthia evecta caused apoptosis in human hepatoma (HepG2) cells

    PubMed Central

    Machana, Sasipawan; Weerapreeyakul, Natthida; Barusrux, Sahapat; Thumanu, Kanjana; Tanthanuch, Waraporn

    2012-01-01

    Objective To evaluate the anticancer activity of the extract fraction of Polyalthia evecta (P. evecta) (Pierre) Finet & Gagnep and the synergistic anticancer effect of the extracts from P. evecta by using the ATR/FT-IR spectroscopy. Methods The 50% ethanol-water crude leaf extract of P. evecta (EW-L) was prepared and was further fractionated to isolate various fractions. The anticancer activity was investigated from cytotoxicity against HepG2 using a neutral red assay and apoptosis induction by evaluation of nuclei morphological changes after DAPI staining. Synergistic anticancer effects of the extracts from P. evecta were performed using the ATR/FT-IR spectroscopy. Results The result showed that the EW-L showed higher cytotoxicity and apoptosis induction in HepG2 cells than its fractionated extracts. The hexane extract exhibited higher cytotoxicity and apoptosis induction than the water extracts, but less than the EW-L. The combined water and hexane extracts apparently increased cytotoxicity and apoptosis induction. The %apoptotic cells induced by the extract mixture were increased about 2-fold compared to the single hexane extract. Conclusions The polar extract fraction is necessary for the anticancer activity of the non-polar extract fraction. The ATR/FT-IR spectra illustrates the physical interaction among the constituents in the extract mixture and reveals the presence of polyphenolic constituents in the EW-L, which might play a role for the synergistic anticancer effect. PMID:23569977

  2. Curcumin and Ellagic acid synergistically induce ROS generation, DNA damage, p53 accumulation and apoptosis in HeLa cervical carcinoma cells.

    PubMed

    Kumar, Devbrat; Basu, Soumya; Parija, Lucy; Rout, Deeptimayee; Manna, Sanjeet; Dandapat, Jagneshwar; Debata, Priya Ranjan

    2016-07-01

    Cervical cancer and precancerous lesions of the cervix continue to be a global health issue, and the medication for the treatment for chronic HPV infection so far has not been effective. Potential anticancer and anti HPV activities of two known phytochemicals, Curcumin and Ellagic acid were evaluated in HeLa cervical cancer cells. Curcumin is a natural compound found in the root of Curcuma longa plant and Ellagic acid a polyphenol found in fruits of strawberries, raspberries and walnuts. The combination of Curcumin and Ellagic acid at various concentrations showed better anticancer properties than either of the drug when used alone as evidenced by MTT assay. Besides this, Curcumin and Ellagic acid also restore p53, induce ROS formation and DNA damage. Mechanistic study further indicated that Curcumin and Ellagic acid show anti-HPV activity as evidenced by decrease in the HPV E6 oncoprotein on HeLa cells. PMID:27261574

  3. Multiple Active Compounds from Viscum album L. Synergistically Converge to Promote Apoptosis in Ewing Sarcoma.

    PubMed

    Twardziok, Monika; Kleinsimon, Susann; Rolff, Jana; Jäger, Sebastian; Eggert, Angelika; Seifert, Georg; Delebinski, Catharina I

    2016-01-01

    Ewing sarcoma is the second most common bone cancer in children and adolescents, with poor prognosis and outcome in ~70% of initial diagnoses and 10-15% of relapses. Hydrophobic triterpene acids and hydrophilic lectins and viscotoxins from European mistletoe (Viscum album L.) demonstrate anticancer properties, but have not yet been investigated for Ewing sarcoma. Commercial Viscum album L. extracts are aqueous, excluding the insoluble triterpenes. We recreated a total mistletoe effect by combining an aqueous extract (viscum) and a triterpene extract (TT) solubilized with cyclodextrins. Ewing sarcoma cells were treated with viscum, TT and viscumTT in vitro, ex vivo and in vivo. In vitro and ex vivo treatment of Ewing sarcoma cells with viscum inhibited proliferation and induced apoptosis in a dose-dependent fashion, while viscumTT combination treatment generated a synergistic effect. Apoptosis occurred via intrinsic and extrinsic apoptotic pathways, evidenced by activation of both CASP8 and CASP9. We show that viscumTT treatment shifts the balance of apoptotic regulatory proteins towards apoptosis, mainly via CLSPN, MCL1, BIRC5 and XIAP downregulation. ViscumTT also demonstrated strong antitumor activity in a cell line- and patient-derived mouse model, and may be considered an adjuvant therapy option for pediatric patients with Ewing sarcoma. PMID:27589063

  4. Phellinus linteus sensitises apoptosis induced by doxorubicin in prostate cancer

    PubMed Central

    Collins, L; Zhu, T; Guo, J; Xiao, Z J; Chen, C-Y

    2006-01-01

    It has been demonstrated that the Phellinus linteus (PL) mushroom, which mainly consists of polysaccharides, possesses antitumour activity. The mechanisms of PL against malignant growth remain unknown. The anticancer drug doxorubicin (Dox) has been shown to induce apoptosis via initiating a caspase cascade. In this investigation, we tested the effect of PL on Dox-induced apoptosis in prostate cancer LNCaP cells. We showed that PL or Dox, at relatively low doses, does not induce apoptosis in the cells. However, combination treatment with low doses of PL and Dox results in a synergistic effect on the induction of apoptosis. In this apoptotic process, caspases 8, 3 and BID are cleaved, and the addition of caspase inhibitor z-VADfmk completely blocks apoptosis. In addition, JNK is activated in response to PL or the combination treatment in LNCaP cells. The suppression of JNK partially inhibits the induction of apoptosis elicited by the co-treatment. These findings indicate that PL has a synergistic effect with Dox to activate caspases in prostate cancer LNCaP cells. Our study also suggests that PL has therapeutic potential to augment the magnitude of apoptosis induced by antiprostate cancer drugs. PMID:16868541

  5. Synergistic effects between catalase inhibitors and modulators of nitric oxide metabolism on tumor cell apoptosis.

    PubMed

    Scheit, Katrin; Bauer, Georg

    2014-10-01

    Inhibitors of catalase (such as ascorbate, methyldopa, salicylic acid and neutralizing antibodies) synergize with modulators of nitric oxide (NO) metabolism (such as arginine, arginase inhibitor, NO synthase-inducing interferons and NO dioxygenase inhibitors) in the singlet oxygen-mediated inactivation of tumor cell protective catalase. This is followed by reactive oxygen species (ROS)-dependent apoptosis induction. TGF-beta, NADPH oxidase-1, NO synthase, dual oxidase-1 and caspase-9 are characterized as essential catalysts in this process. The FAS receptor and caspase-8 are required for amplification of ROS signaling triggered by individual compounds, but are dispensable when the synergistic effect is established. Our findings explain the antitumor effects of catalase inhibitors and of compounds that target NO metabolism, as well as their synergy. These data may have an impact on epidemiological studies related to secondary plant compounds and open new perspectives for the establishment of novel antitumor drugs and for the improvement of established chemotherapeutics. PMID:25275027

  6. Timing determines dexamethasone and rituximab induced synergistic cell death.

    PubMed

    Adem, Jemal; Eray, Mine; Eeva, Jonna; Nuutinen, Ulla; Pelkonen, Jukka

    2016-07-01

    Dysregulation of cell death signaling pathways in many cell types such as B lymphocytes (B-cells) can lead to cancer, for example to B-cell lymphomas. Rituximab (RTX) and glucocorticoids such as dexamethasone (Dex) are widely used to treat hematological malignancies including B-cell lymphomas. Although the combination of Dex and RTX improves the treatment outcome of lymphoma patients, most lymphomas remain incurable diseases. Therefore, a detailed investigation of Dex- and RTX-induced signaling might provide new insights into the therapeutic benefits of these drugs. In this paper, we describe Dex- and RTX-induced signaling pathways and their downstream target proteins/cells. In addition, we also overview how the signaling initiated by Dex and RTX modulate the outcome of Dex- and RTX-mediated cell death in lymphoma cells. The combination of Dex and RTX results in massive cell death in lymphoma cells. However, pretreatment of lymphoma cells or mononuclear cytotoxic cells with Dex followed by RTX leads to a decrease in apoptosis or it impairs antibody-dependent cellular cytotoxicity (ADCC). RTX-mediated ADCC is impaired by Dex-induced depletion of cytotoxic cells, whereas RTX-mediated short-term ERK1/2 activation decreases Dex-induced apoptosis. Therefore, the timing of the combination of Dex and RTX is a determining factor for the synergistic effect of these cell death inducing agents. PMID:27290654

  7. The synergistic effect of resveratrol in combination with cisplatin on apoptosis via modulating autophagy in A549 cells.

    PubMed

    Hu, Song; Li, Xiaolin; Xu, Rongrong; Ye, Lingyun; Kong, Hui; Zeng, Xiaoning; Wang, Hong; Xie, Weiping

    2016-06-01

    Several studies have shown that combination treatment with natural products and chemotherapy agents can improve the sensitivity and cytotoxicity of chemotherapy agents. Resveratrol, a natural product, has many biological effects including antitumor and antiviral activities, as well as vascular protective effect. The aim of this study is to investigate the synergistic anticancer effect of resveratrol in combination with cisplatin and the potential anticancer mechanisms involved in A549 cells. The results obtained from Cell Counting Kit-8 and isobolographic analysis demonstrated that combination of resveratrol and cisplatin resulted in synergistic cytotoxic effects in A549 cells. Results from Hoechst staining, flow cytometry and western blot analysis suggested that resveratrol enhanced cisplatin-mediated apoptosis. Meanwhile, the changes of LC3-II and P62 levels and formation of autophagosome suggested that resveratrol in combination with cisplatin triggered autophagy. More importantly, inhibiting autophagy by 3-methyladenine markedly attenuated the apoptosis caused by combination of resveratrol and cisplatin in A549 cells. Taken together, our study provides the first evidence that resveratrol combined with cisplatin synergistically induce apoptosis via modulating autophagic cell death in A549 cells. These findings also help us to understand the role of natural products in combination with chemotherapy agents in lung cancer. PMID:27084520

  8. Calmodulin antagonists induce platelet apoptosis.

    PubMed

    Wang, Zhicheng; Li, Suping; Shi, Quanwei; Yan, Rong; Liu, Guanglei; Dai, Kesheng

    2010-04-01

    Calmodulin (CaM) antagonists induce apoptosis in various tumor models and inhibit tumor cell invasion and metastasis, thus some of which have been extensively used as anti-cancer agents. In platelets, CaM has been found to bind directly to the cytoplasmic domains of several platelet receptors. Incubation of platelets with CaM antagonists impairs the receptors-related platelet functions. However, it is still unknown whether CaM antagonists induce platelet apoptosis. Here we show that CaM antagonists N-(6-aminohexyl)-5-chloro-1-naphthalene sulfonamide (W7), tamoxifen (TMX), and trifluoperazine (TFP) induce apoptotic events in human platelets, including depolarization of mitochondrial inner transmembrane potential, caspase-3 activation, and phosphatidylserine exposure. CaM antagonists did not incur platelet activation as detected by P-selectin surface expression and PAC-1 binding. However, ADP-, botrocetin-, and alpha-thrombin-induced platelet aggregation, platelet adhesion and spreading on von Willebrand factor surface were significantly reduced in platelets pre-treated with CaM antagonists. Furthermore, cytosolic Ca(2+) levels were obviously elevated by both W7 and TMX, and membrane-permeable Ca(2+) chelator BAPTA-AM significantly reduced apoptotic events in platelets induced by W7. Therefore, these findings indicate that CaM antagonists induce platelet apoptosis. The elevation of the cytosolic Ca(2+) levels may be involved in the regulation of CaM antagonists-induced platelet apoptosis. PMID:20172594

  9. Synergistic interaction between enalapril, L-arginine and tetrahydrobiopterin in smooth muscle cell apoptosis and aortic remodeling induction in SHR

    PubMed Central

    Sarkissian, Shant Der; Marchand, Eve-Lyne; Duguay, David; deBlois, Denis

    2004-01-01

    Smooth muscle cell (SMC) apoptosis occurs at the onset of enalapril-induced regression of aortic hypertrophy in SHR. A potential mechanism is the correction of endothelial dysfunction (ED) leading to reduced production of reactive oxygen species and enhanced bioavailability of nitric oxide (NO), a potent apoptosis inducer. Stimulants of NO include the precursor L-arginine and the NO synthase cofactor tetrahydrobiopterin (BH4), which correct ED in several models. The objective was to examine the relationships between ED and the cell growth/death balance during vascular remodeling induced by enalapril in SHR. SHR, 10-week-old, received enalapril (ENA: 30 mg.kg−1.day−1 p.o.) for 1 or 2 weeks, or a co-treatment of L-arginine (2.0 g.kg−1.day−1 p.o.) and BH4 (5.4 mg.kg−1.day−1 i.p. twice daily) administered alone (group: LB) or in combination with enalapril (ENA+LB) for 1 week. Controls received vehicle. After 1 week, ED was completely corrected with LB but not affected significantly by ENA, whereas both treatments failed to induce SMC apoptosis or aortic remodeling. The correction of ED and the induction of SMC apoptosis (3.3-fold increase in TUNEL labeling) required 2 weeks of ENA treatment. The combination of LB with ENA for 1 week, however, was additive for the reduction of SMC proliferation, and synergistic for the induction of apoptosis and regression of vascular hypertrophy. These interactions were independent of blood pressure regulation. Our results suggest that the correction of ED is not sufficient to induce SMC apoptosis and vascular remodeling, although it facilitates these responses during enalapril treatment. PMID:15197102

  10. Meloxicam combined with sorafenib synergistically inhibits tumor growth of human hepatocellular carcinoma cells via ER stress-related apoptosis.

    PubMed

    Zhong, Jingtao; Xiu, Peng; Dong, Xiaofeng; Wang, Fuhai; Wei, Honglong; Wang, Xin; Xu, Zongzhen; Liu, Feng; Li, Tao; Wang, Yong; Li, Jie

    2015-10-01

    Sorafenib (SOR) is a promising treatment for advanced hepatocellular carcinoma (HCC). However, the precise mechanisms of toxicity and drug resistance have not been fully explored and new strategies are urgently needed for HCC therapy. Meloxicam (MEL) is a selective cyclooxygenase-2 (COX-2) inhibitor which elicits antitumor effects in human HCC cells. In the present study, we investigated the interaction between MEL and SOR in human SMMC‑7721 cells and the role endoplasmic reticulum (ER) stress exerts in the combination of SOR with MEL treatment-induced cytotoxicity. Our results revealed that the combination treatment synergistically inhibited cell proliferation and enhanced apoptosis. Furthermore, the combination treatment enhanced ER stress-related molecules which involved in SMMC-7721 cell apoptosis. GRP78 knockdown by siRNA or co-treatment with MG132 significantly increased this combination treatment-induced apoptosis. In addition, we found that the combination treatment suppressed tumor growth by way of activation of ER stress in in vivo models. We concluded that the combination of SOR with MEL treatment-induced ER stress, and eventually apoptosis in human SMMC-7721 cells. Knockdown of GRP78 using siRNA or proteosome inhibitor enhanced the cytotoxicity of the combination of SOR with MEL-treatment in SMMC-7721 cells. These findings provided a new potential treatment strategy against HCC. PMID:26252057

  11. Synergistic chemopreventive effects of curcumin and berberine on human breast cancer cells through induction of apoptosis and autophagic cell death.

    PubMed

    Wang, Kai; Zhang, Chao; Bao, Jiaolin; Jia, Xuejing; Liang, Yeer; Wang, Xiaotong; Chen, Meiwan; Su, Huanxing; Li, Peng; Wan, Jian-Bo; He, Chengwei

    2016-01-01

    Curcumin (CUR) and berberine (BBR) are renowned natural compounds that exhibit potent anticancer activities through distinct molecular mechanisms. However, the anticancer capacity of either CUR or BBR is limited. This prompted us to investigate the chemopreventive potential of co-treatment of CUR and BBR against breast cancers. The results showed that CUR and BBR in combination synergistically inhibited the growth of both MCF-7 and MDA-MB-231 breast cancer cells than the compounds used alone. Further study confirmed that synergistic anti-breast cancer activities of co-treatment of these two compounds was through inducing more apoptosis and autophagic cell death (ACD). The co-treatment-induced apoptosis was caspase-dependent and through activating ERK pathways. Our data also demonstrated that co-treatment of CUR and BBR strongly up-regulated phosphorylation of JNK and Beclin1, and decreased phosphorylated Bcl-2. Inhibition of JNK by SP600125 markedly decreased LC3-II and Beclin1, restored phosphorylated Bcl-2, and reduced the cytotoxicity induced by the two compounds in combination. These results strongly suggested that JNK/Bcl-2/Beclin1 pathway played a key role in the induction of ACD in breast cancer cells by co-treatment of CUR and BBR. This study provides an insight into the potential application of curcumin and berberine in combination for the chemoprevention and treatment of breast cancers. PMID:27263652

  12. Synergistic chemopreventive effects of curcumin and berberine on human breast cancer cells through induction of apoptosis and autophagic cell death

    PubMed Central

    Wang, Kai; Zhang, Chao; Bao, Jiaolin; Jia, Xuejing; Liang, Yeer; Wang, Xiaotong; Chen, Meiwan; Su, Huanxing; Li, Peng; Wan, Jian-Bo; He, Chengwei

    2016-01-01

    Curcumin (CUR) and berberine (BBR) are renowned natural compounds that exhibit potent anticancer activities through distinct molecular mechanisms. However, the anticancer capacity of either CUR or BBR is limited. This prompted us to investigate the chemopreventive potential of co-treatment of CUR and BBR against breast cancers. The results showed that CUR and BBR in combination synergistically inhibited the growth of both MCF-7 and MDA-MB-231 breast cancer cells than the compounds used alone. Further study confirmed that synergistic anti-breast cancer activities of co-treatment of these two compounds was through inducing more apoptosis and autophagic cell death (ACD). The co-treatment-induced apoptosis was caspase-dependent and through activating ERK pathways. Our data also demonstrated that co-treatment of CUR and BBR strongly up-regulated phosphorylation of JNK and Beclin1, and decreased phosphorylated Bcl-2. Inhibition of JNK by SP600125 markedly decreased LC3-II and Beclin1, restored phosphorylated Bcl-2, and reduced the cytotoxicity induced by the two compounds in combination. These results strongly suggested that JNK/Bcl-2/Beclin1 pathway played a key role in the induction of ACD in breast cancer cells by co-treatment of CUR and BBR. This study provides an insight into the potential application of curcumin and berberine in combination for the chemoprevention and treatment of breast cancers. PMID:27263652

  13. Molecular mechanisms of nutlin-induced apoptosis in multiple myeloma

    PubMed Central

    Saha, Manujendra N; Jiang, Hua

    2010-01-01

    Multiple myeloma (MM) is an incurable plasma cell malignancy in which p53 is rarely mutated. Thus, activation of the p53 pathway by a small molecule inhibitor of the p53-MDM2 interaction, nutlin, in MM cells retaining wild type p53 is an attractive therapeutic strategy. Recently we reported that nutlin plus velcade (a proteasome inhibitor) displayed a synergistic response in MM. However, the mechanism of the p53-mediated apoptosis in MM has not been fully understood. Our data show that nutlin-induced apoptosis correlated with reduction in cell viability, upregulation of p53, p21 and MDM2 protein levels with a simultaneous increase in pro-apoptotic targets PUMA, Bax and Bak and downregulation of anti-apoptotic targets Bcl2 and survivin and activation of caspase in MM cells harboring wild type p53. Nutlin-induced apoptosis was inhibited when activation of caspase was blocked by the caspase inhibitor. Nutlin caused mitochondrial translocation of p53 where it binds with Bcl2, leading to cytochrome C release. Moreover, blocking the transcriptional arm of p53 by the p53-specific transcriptional inhibitor, pifithrin-α, not only inhibited nutlin-induced upregulation of p53-transcriptional targets but also augmented apoptosis in MM cells, suggesting an association of transcription-independent pathway of apoptosis. However, inhibitor of mitochondrial translocation of p53, PFT-µ, did not prevent nutlin-induced apoptosis, suggesting that the p53 transcription-dependent pathway was also operational in nutlin-induced apoptosis in MM. Our study provides the evidence that nutlin-induced apoptosis in MM cells is mediated by transcription-dependent and -independent pathways and supports further clinical evaluation of nutlin as a novel therapeutic agent in MM. PMID:20595817

  14. Synergistic inhibition of angiogenesis and glioma cell-induced angiogenesis by the combination of temozolomide and enediyne antibiotic lidamycin

    PubMed Central

    Li, Xing-qi; Ouyang, Zhi-gang; Zhang, Sheng-hua; Liu, Hong; Shang, Yue; Li, Yi; Zhen, Yong-su

    2014-01-01

    Present work mainly evaluated the inhibitory effects of lidamycin (LDM), an enediyne antibiotic, on angiogenesis or glioma-induced angiogenesis in vitro and in vivo, especially its synergistic anti-angiogenesis with temozolomide (TMZ). LDM alone efficiently inhibited proliferations and induced apoptosis of rat brain microvessel endothelial cells (rBMEC). LDM also interrupted the tube formation of rat brain microvessel endothelial cells (rBMEC) and rat aortic ring spreading. The blockade of rBMEC invasion and C6 cell-induced rBMEC migration by LDM was associated with decrease of VEGF secretion in a co-culture system. TMZ dramatically potentiated the effects of LDM on anti-proliferation, apoptosis induction, and synergistically inhibited angiogenesis events. As determined by western blot and ELISA, the interaction of tumor cells and the rBMEC was markedly interrupted by LDM plus TMZ with synergistic regulations of VEGF induced angiogenesis signal pathway, tumor cell invasion/migration, and apoptosis signal pathway. Immunofluorohistochemistry of CD31 and VEGF showed that LDM plus TMZ resulted in synergistic decrease of microvessel density (MVD) and VEGF expression in human glioma U87 cell subcutaneous xenograft. This study indicates that the high efficacy of LDM and the synergistic effects of LDM plus TMZ against glioma are mediated, at least in part, by the potentiated anti-angiogenesis. PMID:24424202

  15. Synergistic inhibition of angiogenesis and glioma cell-induced angiogenesis by the combination of temozolomide and enediyne antibiotic lidamycin.

    PubMed

    Li, Xing-Qi; Ouyang, Zhi-Gang; Zhang, Sheng-Hua; Liu, Hong; Shang, Yue; Li, Yi; Zhen, Yong-Su

    2014-04-01

    Present work mainly evaluated the inhibitory effects of lidamycin (LDM), an enediyne antibiotic, on angiogenesis or glioma-induced angiogenesis in vitro and in vivo, especially its synergistic anti-angiogenesis with temozolomide (TMZ). LDM alone efficiently inhibited proliferations and induced apoptosis of rat brain microvessel endothelial cells (rBMEC). LDM also interrupted the tube formation of rat brain microvessel endothelial cells (rBMEC) and rat aortic ring spreading. The blockade of rBMEC invasion and C6 cell-induced rBMEC migration by LDM was associated with decrease of VEGF secretion in a co-culture system. TMZ dramatically potentiated the effects of LDM on anti-proliferation, apoptosis induction, and synergistically inhibited angiogenesis events. As determined by western blot and ELISA, the interaction of tumor cells and the rBMEC was markedly interrupted by LDM plus TMZ with synergistic regulations of VEGF induced angiogenesis signal pathway, tumor cell invasion/migration, and apoptosis signal pathway. Immunofluorohistochemistry of CD31 and VEGF showed that LDM plus TMZ resulted in synergistic decrease of microvessel density (MVD) and VEGF expression in human glioma U87 cell subcutaneous xenograft. This study indicates that the high efficacy of LDM and the synergistic effects of LDM plus TMZ against glioma are mediated, at least in part, by the potentiated anti-angiogenesis. PMID:24424202

  16. Interleukin-6 (IL-6) and IL-17 Synergistically Promote Viral Persistence by Inhibiting Cellular Apoptosis and Cytotoxic T Cell Function

    PubMed Central

    Hou, Wanqiu; Jin, Young-Hee; Kang, Hyun Seok

    2014-01-01

    ABSTRACT Interleukin-6 (IL-6) plays an important role in the development and progression of inflammatory responses, autoimmune diseases, and cancers. Many viral infections, including Theiler's murine encephalomyelitis virus (TMEV), result in the vigorous production of IL-6. However, the role of IL-6 in the development of virus-induced inflammatory responses is unclear. The infection of susceptible mice with TMEV induces the development of chronic demyelinating disease, which is considered a relevant infectious model for multiple sclerosis. In this study, we demonstrate that resistant C57BL/6 mice carrying an IL-6 transgene (IL-6 Tg) develop a TMEV-induced demyelinating disease accompanied by an increase in viral persistence and an elevated Th17 cell response in the central nervous system. Either IL-6 or IL-17 induced the expression of Bcl-2 and Bcl-xL at a high concentration. The upregulated expression of prosurvival molecules in turn inhibited target cell destruction by virus-specific CD8+ T cells. More interestingly, IL-6 and IL-17 synergistically promoted the expression of these prosurvival molecules, preventing cellular apoptosis at a much lower (<5-fold) concentration. The signals involved in the synergy appear to include the activation of both STAT3 and NF-κB via distinct cytokine-dependent pathways. Thus, the excessive IL-6 promotes the generation of Th17 cells, and the resulting IL-6 and IL-17 synergistically promote viral persistence by protecting virus-infected cells from apoptosis and CD8+ T cell-mediated target destruction. These results suggest that blocking both IL-6 and IL-17 functions are important considerations for therapies of chronic viral diseases, autoimmune diseases, and cancers. IMPORTANCE This study indicates that an excessive level of IL-6 cytokine produced following viral infection promotes the development of IL-17-producing pathogenic helper T cells. We demonstrate here for the first time that IL-6 together with IL-17 synergistically

  17. Concurrent targeting of eicosanoid receptor 1/eicosanoid receptor 4 receptors and COX-2 induces synergistic apoptosis in Kaposi's sarcoma-associated herpesvirus and Epstein-Barr virus associated non-Hodgkin lymphoma cell lines.

    PubMed

    Paul, Arun George; Chandran, Bala; Sharma-Walia, Neelam

    2013-06-01

    The effective antitumorigenic potential of nonsteroidal anti-inflammatory drugs (NSAIDs) and eicosonoid (EP; EP1-4) receptor antagonists prompted us to test their efficacy in Kaposi's sarcoma-associated herpesvirus (KSHV) and Epstein-Barr virus (EBV) related lymphomas. Our study demonstrated that (1) EP1-4 receptor protein levels vary among the various non-Hodgkin's lymphoma (NHL) cell lines tested (BCBL-1:KSHV+/EBV-;BC-3: KSHV+/EBV-; Akata/EBV+: KSHV-/EBV+; and JSC-1 cells: KSHV+/EBV + cells); (2) 5.0 μM of EP1 antagonist (SC-51322) had a significant antiproliferative effect on BCBL-1, BC-3, Akata/EBV+, and JSC-1 cells; (3) 50.0 μM of EP2 antagonist (AH6809) was required to induce a significant antiproliferative effect on BCBL-1, Akata/EBV+, and JSC-1 cells; (4) 5.0 μM of EP4 antagonist (GW 627368X) had a significant antiproliferative effect on BC-3, Akata/EBV+, and JSC-1 cells; (5) COX-2 selective inhibitor celecoxib (5.0 μM) had significant antiproliferative effects on BCBL-1, BC-3, Akata/EBV+, and JSC-1 cells; and (6) a combination of 1.0 μM each of celecoxib, SC-51322 and GW 627368X could potentiate the proapoptotic properties of celecoxib or vice-versa. Overall, our studies identified the synergistic antiproliferative effect of NSAIDs and EP receptor blockers on KSHV and EBV related B cell malignancies. PMID:23523954

  18. Dacarbazine and the Agonistic TRAIL Receptor-2 Antibody Lexatumumab Induce Synergistic Anticancer Effects in Melanoma

    PubMed Central

    Engesæter, Birgit; Engebraaten, Olav; Flørenes, Vivi Ann; Mælandsmo, Gunhild Mari

    2012-01-01

    Mapatumumab and lexatumumab (targeting death receptor 4 (DR4) and 5 (DR5), respectively) are agonistic TRAIL receptor antibodies that induce apoptosis in a wide range of cancer cells. The potency of mapatumumab and lexatumumab was assessed in mono therapy protocols, and the ability to sensitize for dacarbazine (DTIC) treatment was explored in ten different melanoma cell lines. Our data indicated that melanoma cell lines tend to be resistant to mapatumumab, most likely due to low expression of DR4, while a dose dependent response to lexatumumab was observed. Combining DTIC and lexatumumab induced an additive or synergistic effect on cell death in the various melanoma cell lines. The synergistic effect observed in the FEMX-1 cell line was related to enhanced cleavage of Bid in parallel with elevated expression of the pro-apoptotic proteins Bim, Bax and Bak. Furthermore, the anti-apoptotic proteins Bcl-XL, cIAP-1, XIAP and livin were down regulated. Cleavage of Bid and down regulation of cIAP-2 and livin were observed in vivo. Altogether, these data suggest a change in the balance between pro- and anti-apoptotic proteins favoring induction of apoptosis. In the more therapy resistant cell line, HHMS, no changes in the pro- and anti-apoptotic proteins were observed. FEMX-1 xenografts treated with DTIC and lexatumumab showed reduced growth and increased level of apoptosis compared to the control groups, providing arguments for further evaluation of this combination in melanoma patients. PMID:23029050

  19. Apoptosis inducers in chronic lymphocytic leukemia

    PubMed Central

    Billard, Christian

    2014-01-01

    Chronic lymphocytic leukemia (CLL) is characterized by a typical defect in apoptosis and is still an incurable disease. Numerous apoptosis inducers have been described. These synthetic compounds and natural products (mainly derived from plants) display antileukemic properties in vitro and in vivo and some have even been tested in the clinic in CLL. They act through several different mechanisms. Most of them involve proteins of the Bcl-2 family, which are the key regulators in triggering the mitochondrial pathway of caspase-dependent apoptosis. Thus, the Mcl-1/Noxa axis appeared as a target. Here I overview natural and synthetic apoptosis inducers and their mechanisms of action in CLL cells. Opportunities for developing novel, apoptosis-based therapeutics are presented. PMID:24525395

  20. Synergistic Myeloma Cell Death via Novel Intracellular Activation of Caspase-10-Dependent Apoptosis by Carfilzomib and Selinexor.

    PubMed

    Rosebeck, Shaun; Alonge, Mattina M; Kandarpa, Malathi; Mayampurath, Anoop; Volchenboum, Samuel L; Jasielec, Jagoda; Dytfeld, Dominik; Maxwell, Sean P; Kraftson, Stephanie J; McCauley, Dilara; Shacham, Sharon; Kauffman, Michael; Jakubowiak, Andrzej J

    2016-01-01

    Exportin1 (XPO1; also known as chromosome maintenance region 1, or CRM1) controls nucleo-cytoplasmic transport of most tumor suppressors and is overexpressed in many cancers, including multiple myeloma, functionally impairing tumor suppressive function via target mislocalization. Selective inhibitor of nuclear export (SINE) compounds block XPO1-mediated nuclear escape by disrupting cargo protein binding, leading to retention of tumor suppressors, induction of cancer cell death, and sensitization to other drugs. Combined treatment with the clinical stage SINE compound selinexor and the irreversible proteasome inhibitor (PI) carfilzomib induced synergistic cell death of myeloma cell lines and primary plasma cells derived from relapsing/refractory myeloma patients and completely impaired the growth of myeloma cell line-derived tumors in mice. Investigating the details of SINE/PI-induced cell death revealed (i) reduced Bcl-2 expression and cleavage and inactivation of Akt, two prosurvival regulators of apoptosis and autophagy; (ii) intracellular membrane-associated aggregation of active caspases, which depended on caspase-10 protease activity; and (iii) novel association of caspase-10 and autophagy-associated proteins p62 and LC3 II, which may prime activation of the caspase cascade. Overall, our findings provide novel mechanistic rationale behind the potent cell death induced by combining selinexor with carfilzomib and support their use in the treatment of relapsed/refractory myeloma and potentially other cancers. PMID:26637366

  1. Lysosomal destabilization in p53-induced apoptosis

    PubMed Central

    Yuan, Xi-Ming; Li, Wei; Dalen, Helge; Lotem, Joseph; Kama, Rachel; Sachs, Leo; Brunk, Ulf T.

    2002-01-01

    The tumor suppressor wild-type p53 can induce apoptosis. M1-t-p53 myeloid leukemic cells have a temperature-sensitive p53 protein that changes its conformation to wild-type p53 after transfer from 37°C to 32°C. We have now found that these cells showed an early lysosomal rupture after transfer to 32°C. Mitochondrial damage, including decreased membrane potential and release of cytochrome c, and the appearance of apoptotic cells occurred later. Lysosomal rupture, mitochondrial damage, and apoptosis were all inhibited by the cytokine IL-6. Some other compounds can also inhibit apoptosis induced by p53. The protease inhibitor N-tosyl-l-phenylalanine chloromethyl ketone inhibited the decrease in mitochondrial membrane potential and cytochrome c release, the Ca2+-ATPase inhibitor thapsigargin inhibited only cytochrome c release, and the antioxidant butylated hydroxyanisole inhibited only the decrease in mitochondrial membrane potential. In contrast to IL-6, these other compounds that inhibited some of the later occurring mitochondrial damage did not inhibit the earlier p53-induced lysosomal damage. The results indicate that apoptosis is induced by p53 through a lysosomal-mitochondrial pathway that is initiated by lysosomal destabilization, and that this pathway can be dissected by using different apoptosis inhibitors. These findings on the induction of p53-induced lysosomal destabilization can also help to formulate new therapies for diseases with apoptotic disorders. PMID:11959917

  2. Synergistic anticancer effect of cisplatin and Chal-24 combination through IAP and c-FLIPL degradation, Ripoptosome formation and autophagy-mediated apoptosis

    PubMed Central

    Shi, Shaoqing; Wang, Qiong; Xu, Jennings; Jang, Jun-Ho; Padilla, Mabel T.; Nyunoya, Toru; Xing, Chengguo; Zhang, Lin; Lin, Yong

    2015-01-01

    Drug resistance is a major hurdle in anticancer chemotherapy. Combined therapy using drugs with distinct mechanisms of function may increase anticancer efficacy. We have recently identified the novel chalcone derivative, chalcone-24 (Chal-24), as a potential therapeutic that kills cancer cells through activation of an autophagy-mediated necroptosis pathway. In this report, we investigated if Chal-24 can be combined with the frontline genotoxic anticancer drug, cisplatin for cancer therapy. The combination of Chal-24 and cisplatin synergistically induced apoptotic cytotoxicity in lung cancer cell lines, which was dependent on Chal-24-induced autophagy. While cisplatin slightly potentiated the JNK/Bcl2/Beclin1 pathway for autophagy activation, its combination with Chal-24 strongly triggered proteasomal degradation of the cellular inhibitor of apoptosis proteins (c-IAPs) and formation of the Ripoptosome complex that contains RIP1, FADD and caspase 8. Furthermore, the cisplatin and Chal-24 combination induced dramatic degradation of cellular FLICE (FADD-like IL-1β-converting enzyme)-inhibitory protein large (cFLIPL) which suppresses Ripoptosome-mediated apoptosis activation. These results establish a novel mechanism for potentiation of anticancer activity with the combination of Chal-24 and cisplatin: to enhance apoptosis signaling through Ripoptosome formation and to release the apoptosis brake through c-FLIPL degradation. Altogether, our work suggests that the combination of Chal-24 and cisplatin could be employed to improve chemotherapy efficacy. PMID:25682199

  3. Training-induced apoptosis in skeletal muscle.

    PubMed

    Boffi, F M; Cittar, J; Balskus, G; Muriel, M; Desmaras, E

    2002-09-01

    Apoptosis or programmed cell death is a genetically controlled response of cells to commit suicide and is associated with DNA fragmentation or laddering. The common inducers of apoptosis include Ca2+i and oxygen free radicals/oxidative stress, which are also implicated in the pathogenesis of exercise-induced myopathies. To examine training-induced apoptosis, Thoroughbred horses were subjected to 3 months training programme on a treadmill. At the end of the training programme venous blood samples were taken for a creatine kinase (CK) assay. In addition, muscle biopsy samples were obtained for a membrane lipid peroxidation measurement by malondialdehyde (MDA) assay and for apoptosis detection. Apoptosis was studied by visualising the apoptotic myocytes on the paraffin sections by the modified TUNEL method. DNA laddering was evaluated by subjecting the DNA obtained from the biopsies to 1.5% agarose gel electrophoresis. There was a significant increase (P<0.05) of protein-bound MDA, and a nonsignificant trend (P = 0.14) for the control group to have higher levels of CK compared to the trained group. Under light microscopy, percentage of the TUNEL positive cells was higher (P<0.001) in the training group. This result was corroborated with the findings of DNA fragmentation by gel electrophoresis, which showed higher ladders of DNA band at the same group. In conclusion, these results clearly demonstrate that there is training-induced apoptosis in skeletal muscle. It is probable that apoptosis allows the work/recovery/rebound/supercompensation cycle, when unaccustomed muscle cells activate programmed cell death and are replaced by new and stronger cells, which is the mechanism for training-induced increases in fitness. PMID:12405700

  4. Sodium nitroprusside induces apoptosis of rabbit chondrocytes

    NASA Astrophysics Data System (ADS)

    Liang, Qian; Wang, Xiao-Ping; Chen, Tong-Sheng

    2013-02-01

    Osteoarthritis (OA) is characterized by a slowly progressing degradation of the matrix and destruction of articular cartilage. Apoptosis of chondrocyte is accounted for the mechanism of OA. Nitric oxide (NO), as a stimulus, has been shown to induce chondrocyte apoptosis by activating the matrix metalloproteinases (MMPs), increasing the expression of cyclooxygenase 2 (COX-2) and the level of prostaglandin E2 (PGE2), inhibiting the proteoglycan synthesis and type II collagen expression. In this study, sodium nitroprusside (SNP) was administered to be the NO donor to explore the mechanism of NO-induced apoptosis of rabbit chondrocytes obtained from six weeks old New Zealand rabbits. CCK-8 assay revealed the inhibitory effect of SNP on cell viability. We used flow cytometry (FCM) to assess the form of cell death by Annexin-V/propidium iodide (PI) double staining, and evaluate the change of mitochondrial membrane potential (ΔΨm). We found that the SNP induced chondrocyte apoptosis in a dose- and time-dependent manner and an observable reduction of ΔΨm. In conclusion, our findings indicate that SNP induces apoptosis of rabbit chondrocytes via a mitochondria-mediated pathway.

  5. Umbelliprenin Induces Apoptosis in CLL Cell Lines

    PubMed Central

    Ziai, Seyed Ali; Gholami, Omid; Iranshahi, Mehrdad; Zamani, Amir Hassan; Jeddi-Tehrani, Mahmood

    2012-01-01

    Chronic lymphocytic leukemia (CLL) remains an incurable disease that requires innovative new approaches to improve therapeutic outcome. Many Ferula species, including F. asa-foetida, synthesize terpenyloxy coumarins. One of these coumarins is umbelliprenin, which has been implicated with induction of apoptosis in some cancer cell lines. In this study induction of apoptosis by umbelliprenin on Jurkat T-CLL and Raji B-CLL cell lines was studied. In this regard, cells were incubated with various concentrations of umbelliprenin in-vitro for different times and assayed for apoptosis with annexin V–FITC/PI double staining flowcytometry method. Results showed that umbelliprenin induced apoptosis in leukemic cells in a dose- and time-dependent manner and that CLL cells were more susceptible to umbelliprenin induced cell death than normal peripheral blood mononuclear cell (PBMCs). Moreover, we study the induction of apoptosis in Jurkat cells by umbelliprenin in the presence of interleukin 4 (IL-4) as an agent that causes resistance to apoptosis in CLL cells, was also student. We showed that IL-4 can not reduce apoptotic effect of umbelliprenin. The preferential toxicity of umbelliprenin for CLL cells, supports the hypothesis that oral administration of umbelliprenin in the form of foods or folk medicines containing this coumarin, might enhance protection against the development of CLL in man with little side effects. In conclusion, umbelliprenin may be an effective therapeutic agent in the treatment of CLL, and thus clinical studies with umbelliprenin may be appropriate. PMID:24250490

  6. The synergistic effect of ethanol and shock insults on Caco-2 cytokine production and apoptosis.

    PubMed

    Amin, Parth B; Diebel, Lawrence N; Liberati, David M

    2008-05-01

    Gut epithelial cells are important in orchestrating immunoinflammatory responses in the gut and may impact systemic immunocompetent cells after shock and trauma. Ethanol (EtOH) intoxication is an important etiological factor in trauma and may increase the likelihood of posttraumatic septic complications. Both EtOH and gut I/R impair intestinal barrier function. However, their combined effects on intestinal epithelial cell function and barrier integrity are unknown. Confluent CaCO2 cell monolayers were grown in a two-chamber culture system and exposed to 0.1% EtOH and/or Escherichia coli C-25 under normoxic (21% O2) or hypoxia (5% O2) followed by reoxygenation (H/R). Apical and basal compartment supernatants were collected, and TNF and IL-6 were quantitated by enzyme-linked immunosorbent assay (picograms per milliliter). CaCO2 cell integrity was indexed by apoptosis and monolayer permeability. TNF-alpha production by CaCO2 cells are greatest when incubated with EtOH and then exposed to H/R group. The apical levels of TNF production are consistently higher than basal levels, although the trend toward increased cytokine production is similar in both compartments. IL-6 production by the CaCO2 cell is also greatest when CaCO2 cells incubated with EtOH undergoes H/R. Lastly, the findings in apoptosis mirror the data of the TNF production in the apical compartment. Ethanol and H/R have a synergistic effect on cytokine production and barrier dysfunction in this model. They may also contribute to increased infectious complications and posttraumatic organ failure. PMID:18414237

  7. Nuphar lutea thioalkaloids inhibit the nuclear factor kappaB pathway, potentiate apoptosis and are synergistic with cisplatin and etoposide.

    PubMed

    Ozer, Janet; Eisner, Nadav; Ostrozhenkova, Elena; Bacher, Adelbert; Eisenreich, Wolfgang; Benharroch, Daniel; Golan-Goldhirsh, Avi; Gopas, Jacob

    2009-10-01

    We screened thirty-four methanolic plant extracts for inhibition of the constitutive nuclear factor kappaB (NFkappaB) activity by a NFkappaB-luciferase reporter gene assay. Strong inhibition of NFkappaB activity was found in extracts of leaf and rhizome from Nuphar lutea L. SM. (Nuphar). The inhibitory action was narrowed down to a mixture of thionupharidines and/or thionuphlutidines that were identified in chromatography fractions by one- and two-dimensional NMR analysis. Dimeric sesquiterpene thioalkaloids were identified as the major components of the mixture. The Nuphar alkaloids mixture (NUP) showed a dose dependent inhibition of NFkappaB activity in a luciferase reporter gene assay as well as reduction of nuclear NFkappaB subunits expression as tested by western blots and immunohistochemistry. Decreased DNA binding was demonstrated in electro mobility shift assays. NUP inhibited both inducible and constitutive NFkappaB activation and affected the canonical and alternative pathways. Suppression of NFkappaB was not cell type specific. Induction of apoptosis by the alkaloid mixture was demonstrated by time-dependent and dose-dependent cleavage of procaspase-9 and PARP. Synergistic cytotoxicity of the active mixture with cisplatin and etoposide was demonstrated. Overall, our results show that NUP inhibits the NFkappaB pathway and acts as a sensitizer to conventional chemotherapy, enabling the search for its specific target and application against cancer and inflammation. PMID:19713755

  8. Co-targeting of Bcl-2 and mTOR pathway triggers synergistic apoptosis in BH3 mimetics resistant acute lymphoblastic leukemia

    PubMed Central

    Allegretti, Matteo; Mirabilii, Simone; Licchetta, Roberto; Bergamo, Paola; Rinaldo, Cinzia; Zeuner, Ann; Foà, Robin; Milella, Michele; McCubrey, James A.; Martelli, Alberto M.; Tafuri, Agostino

    2015-01-01

    Several chemo-resistance mechanisms including the Bcl-2 protein family overexpression and constitutive activation of the PI3K/Akt/mTOR signaling have been documented in acute lymphoblastic leukemia (ALL), encouraging targeted approaches to circumvent this clinical problem. Here we analyzed the activity of the BH3 mimetic ABT-737 in ALL, exploring the synergistic effects with the mTOR inhibitor CCI-779 on ABT-737 resistant cells. We showed that a low Mcl-1/Bcl-2 plus Bcl-xL protein ratio determined ABT-737 responsiveness. ABT-737 exposure further decreased Mcl-1, inducing apoptosis on sensitive models and primary samples, while not affecting resistant cells. Co-inhibition of Bcl-2 and the mTOR pathway resulted cytotoxic on ABT-737 resistant models, by downregulating mTORC1 activity and Mcl-1 in a proteasome-independent manner. Although Mcl-1 seemed to be critical, ectopic modulation did not correlate with apoptosis changes. Importantly, dual targeting proved effective on ABT-737 resistant samples, showing additive/synergistic effects. Together, our results show the efficacy of BH3 mimetics as single agent in the majority of the ALL samples and demonstrate that resistance to ABT-737 mostly correlated with Mcl-1 overexpression. Co-targeting of the Bcl-2 protein family and mTOR pathway enhanced drug-induced cytotoxicity by suppressing Mcl-1, providing a novel therapeutic approach to overcome BH3 mimetics resistance in ALL. PMID:26392332

  9. Synergistic killing of lung cancer cells by cisplatin and radiation via autophagy and apoptosis.

    PubMed

    Liu, Min; Ma, Shumei; Liu, Mingbo; Hou, Yufei; Liang, Bing; Su, Xu; Liu, Xiaodong

    2014-06-01

    Cisplatin is a commonly used drug for chemotherapy, however, whether it may be used synergistically with radiotherapy remains unclear. The present study investigated the underlying mechanisms of synergistic killing by radiosensitization and cisplatin, with a focus on the growth inhibition, apoptosis and autophagy of non-small cell human lung cancer cells in vitro and in a tumor xenograft in vivo. A549 cells were used for the in vitro experiments and divided into the following four treatment groups: Sham-irradiated; conventional radiotherapy (CRT) of five doses of 2 Gy every day; hyperfractionated radiotherapy of five doses of 2 Gy (1 Gy twice a day at 4 h intervals) every day; and CRT plus cisplatin. A xenograft tumor-bearing C57BL/6 model was established for the in vivo experiments and the above-mentioned treatments were administered. MTT and colony formation assays were used to detect cell viability and western blotting was performed to detect the levels of protein expression. Monodansylcadaverine staining and the immunofluorescence technique were used to analyze the autophagy rate, while flow cytometry and immunohistochemistry were performed to detect the expression levels of the genes associated with apoptosis and autophagy, including microtubule-associated protein 1 light chain 3 (MAPLC3)-II, phosphoinositide 3-kinase (PI3K) III, Beclin1, phosphorylated protein kinase B (p-AKT), damage-regulated autophagy modulator (DRAM), B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein, caspase-3 and p21. The MTT assay demonstrated that cisplatin exhibits a dose-dependent cytotoxicity in A549 cells and synergizes with radiation to promote the cell-killing effect of radiation. In the xenograft mouse model of Lewis cells, cisplatin plus ionizing radiation (IR) (five doses of 2 Gy) yielded the most significant tumor suppression. The autophagic vacuoles, the ratio of MAPLC3-II to MAPLC3-I (LC3-II/LC3-I) and the levels of Beclin1 were found to increase in all treatment

  10. Targeting MUC1-C is synergistic with bortezomib in downregulating TIGAR and inducing ROS-mediated myeloma cell death

    PubMed Central

    Yin, Li; Kufe, Turner; Avigan, David

    2014-01-01

    The proteosome inhibitor bortezomib (BTZ) induces endoplasmic reticulum and oxidative stress in multiple myeloma (MM) cells. The mucin 1 C-terminal subunit (MUC1-C) oncoprotein is aberrantly expressed in most MM cells, and targeting MUC1-C with GO-203, a cell-penetrating peptide inhibitor of MUC1-C homodimerization, is effective in inducing reactive oxygen species (ROS)-mediated MM cell death. The present results demonstrate that GO-203 and BTZ synergistically downregulate expression of the p53-inducible regulator of glycolysis and apoptosis (TIGAR), which promotes shunting of glucose-6-phosphate into the pentose phosphate pathway to generate reduced glutathione (GSH). In turn, GO-203 blocks BTZ-induced increases in GSH and results in synergistic increases in ROS and MM cell death. The results also demonstrate that GO-203 is effective against BTZ-resistant MM cells. We show that BTZ resistance is associated with BTZ-induced increases in TIGAR and GSH levels, and that GO-203 resensitizes BTZ-resistant cells to BTZ treatment by synergistically downregulating TIGAR and GSH. The GO-203/BTZ combination is thus highly effective in killing BTZ-resistant MM cells. These findings support a model in which targeting MUC1-C is synergistic with BTZ in suppressing TIGAR-mediated regulation of ROS levels and provide an experimental rationale for combining GO-203 with BTZ in certain settings of BTZ resistance. PMID:24632713

  11. Synergistic roles of p53 and HIF1α in human renal cell carcinoma-cell apoptosis responding to the inhibition of mTOR and MDM2 signaling pathways

    PubMed Central

    Liu, Qing-jun; Shen, Hong-liang; Lin, Jun; Xu, Xiu-hong; Ji, Zheng-guo; Han, Xiao; Shang, Dong-hao; Yang, Pei-qian

    2016-01-01

    Introduction mTOR and MDM2 signaling pathways are frequently deregulated in cancer development, and inhibition of mTOR or MDM2 independently enhances carcinoma-cell apoptosis. However, responses to mTOR and MDM2 antagonists in renal cell carcinoma (RCC) remain unknown. Materials and methods A498 cells treated with MDM2 antagonist MI-319 and/or mTOR inhibitor rapamycin were employed in the present study. Cell apoptosis and Western blot analysis were performed. Results and conclusion We found that the MDM2 inhibitor MI-319 induced RCC cell apoptosis mainly dependent on p53 overexpression, while the mTOR antagonist rapamycin promoted RCC cell apoptosis primarily through upregulation of HIF1α expression. Importantly, strong synergistic effects of MI-319 and rapamycin combinations at relatively low concentrations on RCC cell apoptosis were observed. Depletion of p53 or HIF1α impaired both antagonist-elicited apoptoses to differential extents, corresponding to their expression changes responding to chemical treatments, and double knockdown of p53 and HIF1α remarkably hindered MI-319- or rapamycin-induced apoptosis, suggesting that both p53 and HIF1α are involved in MDM2 or mTOR antagonist-induced apoptosis. Collectively, we propose that concurrent activation of p53 and HIF1α may effectively result in cancer-cell apoptosis, and that combined MDM2 antagonists and mTOR inhibitors may be useful in RCC therapy. PMID:26937175

  12. Lithium protects ethanol-induced neuronal apoptosis

    SciTech Connect

    Zhong Jin . E-mail: jizhong@iupui.edu; Yang Xianlin; Yao Weiguo; Lee Weihua

    2006-12-01

    Lithium is widely used for the treatment of bipolar disorder. Recent studies have demonstrated its neuroprotective effect. Ethanol is a potent neurotoxin that is particularly harmful to the developing nervous system. In this study, we evaluated lithium's neuroprotection against ethanol-induced apoptosis. Transient exposure of infant mice to ethanol caused apoptotic cell death in brain, which was prevented significantly by administering a low dose of lithium 15 min later. In cultured cerebellar granule neurons, ethanol-induced apoptosis and activation of caspase-3/9, both of which were prevented by lithium. However, lithium's protection is not mediated by its commonly known inhibition of glycogen synthase3{beta}, because neither ethanol nor lithium has significant effects on the phosphorylation of Akt (ser473) or GSK3{beta} (ser9). In addition, the selective GSK-3{beta} inhibitor SB-415286 was unable to prevent ethanol-induced apoptosis. These data suggest lithium may be used as a potential preventive measure for ethanol-induced neurological deficits.

  13. Farnesol-induced apoptosis in Candida albicans.

    PubMed

    Shirtliff, Mark E; Krom, Bastiaan P; Meijering, Roelien A M; Peters, Brian M; Zhu, Jingsong; Scheper, Mark A; Harris, Megan L; Jabra-Rizk, Mary Ann

    2009-06-01

    Farnesol, a precursor in the isoprenoid/sterol pathway, was recently identified as a quorum-sensing molecule produced by the fungal pathogen Candida albicans. Farnesol is involved in the inhibition of germination and biofilm formation by C. albicans and can be cytotoxic at certain concentrations. In addition, we have shown that farnesol can trigger apoptosis in mammalian cells via the classical apoptotic pathways. In order to elucidate the mechanism behind farnesol cytotoxicity in C. albicans, the response to farnesol was investigated, using proteomic analysis. Global protein expression profiles demonstrated significant changes in protein expression resulting from farnesol exposure. Among the downregulated proteins were those involved in metabolism, glycolysis, protein synthesis, and mitochondrial electron transport and the respiratory chain, whereas proteins involved in folding, protection against environmental and oxidative stress, actin cytoskeleton reorganization, and apoptosis were upregulated. Cellular changes that accompany apoptosis (regulated cell death) were further analyzed using fluorescent microscopy and gene expression analysis. The results indicated reactive oxygen species accumulation, mitochondrial degradation, and positive terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling (TUNEL) in the farnesol-exposed cells concurrent with increased expression of antioxidant-encoding and drug response genes. More importantly, the results demonstrated farnesol-induced upregulation of the caspase gene MCA1 and the intracellular presence of activated caspases. In conclusion, this study demonstrated that farnesol promotes apoptosis in C. albicans through caspase activation, implying an important physiological role for farnesol in the fungal cell life cycle with important implications for adaptation and survival. PMID:19364863

  14. ROS-dependent phosphorylation of Bax by wortmannin sensitizes melanoma cells for TRAIL-induced apoptosis

    PubMed Central

    Quast, S-A; Berger, A; Eberle, J

    2013-01-01

    The pathways of reactive oxygen species (ROS)-mediated apoptosis induction, of Bax activation and the sensitization of tumor cells for TRAIL (TNF-related apoptosis-inducing ligand)-induced apoptosis are still largely elusive. Here, sensitization of melanoma cells for TRAIL by the PI3-kinase inhibitor wortmannin correlated to the activation of mitochondrial apoptosis pathways. Apoptosis was dependent on Bax and abrogated by Bcl-2 overexpression. The synergistic enhancement was explained by Bax activation through wortmannin, which tightly correlated to the characteristic Bax phosphorylation patterns. Thus, wortmannin resulted in early reduction of the Bax-inactivating phosphorylation at serine-184, whereas the Bax-activating phosphorylation at threonine-167 was enhanced. Proving the responsibility of the pathway, comparable effects were obtained with an Akt inhibitor (MK-2206); while suppressed phosphorylation of serine-184 may be attributed to reduced Akt activity itself, the causes of enhanced threonine-167 phosphorylation were addressed here. Characteristically, production of ROS was seen early in response to wortmannin and MK-2206. Providing the link between ROS and Bax, we show that abrogated ROS production by α-tocopherol or by NADPH oxidase 4 (NOX4) siRNA suppressed apoptosis and Bax activation. This correlated with reduced Bax phosphorylation at threonine-167. The data unraveled a mechanism by which NOX4-dependent ROS production controls apoptosis via Bax phosphorylation. The pathway may be considered for proapoptotic, anticancer strategies. PMID:24113173

  15. 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.

  16. Artesunate induces AIF-dependent apoptosis in A549 cells

    NASA Astrophysics Data System (ADS)

    Zhou, Chen-juan; Chen, Tong-Sheng

    2012-03-01

    Artesunate (ART), a semi-synthetic derivative of the sesquiterpene artemisinin extracted from the Chinese herb Artemisia annua, exerts a broad spectrum of clinical activity against human cancers. It has been shown that ART induces cancer cells death through apoptosis pathway. This study investigated whether ART treatment induced reactive oxygen species (ROS)-dependent cell death in the apoptosis fashion in human lung adenocarconoma A549 cell line and the proapoptotic protein apoptosis inducing factor (AIF) is involved in ART-induced apoptosis. Cells treated with ART exhibited typical apoptotic morphology as chromatin condensation, margination and shrunken nucleus. ART treatment also induced a loss of mitochondrial membrane potential and AIF release from mitochondria. Silencing AIF can remarkable attenuated ART-induced apoptosis. Collectively, ART induces apoptosis by caspase-independent intrinsic pathway in A549 cells.

  17. HIV-1 protease-induced apoptosis

    PubMed Central

    2014-01-01

    Background Apoptosis is one of the presumptive causes of CD4+ T cell depletion during HIV infection and progression to AIDS. However, the precise role of HIV-1 in this process remains unexplained. HIV-1 protease (PR) has been suggested as a possible factor, but a direct link between HIV-1 PR enzymatic activity and apoptosis has not been established. Results Here, we show that expression of active HIV-1 PR induces death in HeLa and HEK-293 cells via the mitochondrial apoptotic pathway. This conclusion is based on in vivo observations of the direct localization of HIV-1 PR in mitochondria, a key player in triggering apoptosis. Moreover, we observed an HIV-1 PR concentration-dependent decrease in mitochondrial membrane potential and the role of HIV-1 PR in activation of caspase 9, PARP cleavage and DNA fragmentation. In addition, in vitro data demonstrated that HIV-1 PR mediates cleavage of mitochondrial proteins Tom22, VDAC and ANT, leading to release of AIF and Hsp60 proteins. By using yeast two-hybrid screening, we also identified a new HIV-1 PR interaction partner, breast carcinoma-associated protein 3 (BCA3). We found that BCA3 accelerates p53 transcriptional activity on the bax promoter, thus elevating the cellular level of pro-apoptotic Bax protein. Conclusion In summary, our results describe the involvement of HIV-1 PR in apoptosis, which is caused either by a direct effect of HIV-1 PR on mitochondrial membrane integrity or by its interaction with cellular protein BCA3. PMID:24886575

  18. Sonodynamic therapy induces apoptosis of human leukemia HL-60 cells in the presence of protoporphyrin IX.

    PubMed

    Su, Xiaomin; Wang, Xiaobing; Zhang, Kun; Yang, Shuang; Liu, Quanhong; Leung, Albert W; Xu, Chuanshan; Wang, Pan

    2016-04-01

    Sonodynamic therapy (SDT) is expected to be a novel therapeutic strategy for tumor. The protoporphyrin IX disodium salt (PpIX), a photosensitizer, can be activated by ultrasound. The present study aims to investigate apoptosis of HL-60 cells induced by PpIX-mediated SDT. 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay was adopted to examine cell toxicity. Apoptosis was detected using Annexin V-PE/7-amino-actinomycin D (7-AAD) double staining. Detection of apoptotic bodies was examined by Hoechst33342 (HO) staining. Western blotting was used to analyze the protein of caspase-3 and poly ADP-ribose polymerase (PARP). Intracellular reactive oxygen species (ROS) was detected by a flow cytometer after exposures. Compared with PpIX alone and ultrasound alone groups, the synergistic cytotoxicity of PpIX plus ultrasound were significantly boosted. In addition, as determined by Annexin V-PE/7-AAD staining, SDT significantly induced HL-60 cell apoptosis, the obvious nuclear condensation was also found with HO staining at 4 hours post-SDT treatment. Furthermore, Western blotting showed visible enhancement of caspase-3 and PARP cleavage in this process. Besides, intracellular ROS production was significantly enhanced after SDT. Our findings demonstrate that PpIX-mediated SDT could induce apoptosis on HL-60 cells, suggesting that apoptosis is an important mechanism of cell death induced by PpIX-mediated SDT. PMID:26891272

  19. Measurement of caspase-2 activation during different anti-tumor drugs induced apoptosis by FRET technique

    NASA Astrophysics Data System (ADS)

    Lin, Juqiang; Zeng, Shaoqun; Luo, Qingming; Rong, Chen; Zhang, Zhihong

    2007-11-01

    Caspase-2 is important for the engagement of the mitochondrial apoptotic pathway, in the presence of DNA-damaging agents, such as cisplatin; however, the mechanism by which caspase-2 executes apoptosis remains obscure. In this study, we carried out the measurements of the dynamics of caspase-2 activation in a single living cell by a FRET (fluorescence resonance energy transfer) probe. A FRET probe was constructed that encoded a CRS (caspase-2 recognition site) fused with a cyan fluorescent protein (CFP) and a red fluorescent protein (DsRed) (CFP-CRS-DsRed). Using this probe, we found that during TRAIL-induced apoptosis, caspase-2 was not activated, and caspase-2 activation occurred in etoposide and cisplatin treated cells. However, during cisplatin-induced apoptosis caspase-2 activation was initiated much earlier than that of etoposide. Cisplatin and etoposide is one of the most broadly used drugs in the Clinical applications of cancer chemotherapy, and TRAIL, which belongs to the TNF family proteins, can selectively induce apoptosis in many transformed cells but not in normal cells. Most of anticancer drugs can induce apoptosis mediated by the activation of caspase pathway. Thus, the perfect synergistic effect group of multi-drug can be selected by using our FRET probe.

  20. The Synergistic Effect of Everolimus and Chloroquine on Endothelial Cell Number Reduction Is Paralleled by Increased Apoptosis and Reduced Autophagy Occurrence

    PubMed Central

    Grimaldi, Anna; Balestrieri, Maria Luisa; D'Onofrio, Nunzia; Di Domenico, Gilda; Nocera, Cosimo; Lamberti, Monica; Tonini, Giuseppe; Zoccoli, Alice; Santini, Daniele; Caraglia, Michele; Pantano, Francesco

    2013-01-01

    Endothelial Progenitor Cells (EPCs), a minor subpopulation of the mononuclear cell fraction in peripheral blood, play a critical role in cancer development as they contribute to angiogenesis-mediated pathological neovascularization. In response to tumor cytokines, including VEGF, EPCs mobilize from the bone marrow into the peripheral circulation and move to the tumor bed where they incorporate into sprouting neovessels. In the present study, we evaluated the effects of everolimus (Afinitor, Novartis), a rapamycin analogue, alone or in combination with chloroquine, a 4-alkylamino substituted quinoline family member, one of the autophagy inhibitors, on EPCs biological functions. We found that either everolimus or chloroquine induce growth inhibition on EPCs in a dose-dependent manner after 72 h from the beginning of incubation. The combined administration of the two drugs to EPC was synergistic in inducing growth inhibition; in details, the maximal pharmacological synergism between everolimus and chloroquine in inducing growth inhibition on EPCs cells was recorded when chloroquine was administered 24 h before everolimus. Moreover, we have studied the mechanisms of cell death induced by the two agents alone or in combination on EPCs and we have found that the synergistic effect of combination on EPC growth inhibition was paralleled by increased apoptosis induction and reduced autophagy. These effects occurred together with biochemical features that are typical of reduced autophagic death such as increased co-immunoprecipitation between Beclin 1 and Bcl-2. Chloroquine antagonized the inhibition of the activity of Akt→4EBP1 axis mediated by everolimus and at the same time it blocked the feed-back activation of Erk-1/2 induced by RAD in EPCs. These data suggest a new strategy in order to block angiogenesis in tumours in which this process plays a key role in both the sustainment and spreading of cancer cells. PMID:24244540

  1. Blockade of Inhibitors of Apoptosis Proteins in Combination with Conventional Chemotherapy Leads to Synergistic Antitumor Activity in Medulloblastoma and Cancer Stem-Like Cells

    PubMed Central

    Chen, Shu-Mei; Li, Ying-Ying; Tu, Chiao-Hui; Salazar, Nicole; Tseng, Yuan-Yun; Huang, Shiang-Fu

    2016-01-01

    Background Medulloblastoma (MB) is the most common pediatric primary malignant brain tumor. Approximately one-third of MB patients succumb to treatment failure and some survivors suffer detrimental side effects. Hence, the purpose of this study is to explore new therapeutic regimens to overcome chemotherapeutic agent resistance or reduce chemotherapy-induced toxicity. Methods We detected the expression of inhibitors of apoptosis proteins (IAPs) in MB and CD133+ MB cell lines and MB tissues using immunoblotting and immunohistochemical staining. The antitumor effects of inhibitors against IAPs on MB or CD133+ MB cells were evaluated by MTT assay, Annexin V/PI analysis, and caspase-3/7 activity. Autophagy was assessed by the conversion of light chain (LC) 3-I to LC3-II and Cyto-ID autophagy detection kit. Results MB cells showed higher expression of IAPs compared to normal astrocytes and normal brain tissues. Conventional chemotherapeutic agents combined with small-molecule IAP inhibitors (LCL161 or LBW242) showed a synergistic effect in MB cells. Combined treatments triggered apoptosis in MB cells through activation of caspase-3/7 and autophagic flux simultaneously. In addition, we found that CD133+ MB cells with features of cancer stem cells displayed higher levels of X-linked inhibitor of apoptosis (XIAP) and cellular inhibitor of apoptosis 1/2 (cIAP1/2), and were hypersensitive to treatment with IAP inhibitors. Conclusions These results shed light on the biological effects of combination therapy on MB cells and illustrate that IAP inhibitors are more effective for CD133+ stem-like MB cells. PMID:27537345

  2. Rabies virus matrix protein induces apoptosis by targeting mitochondria.

    PubMed

    Zan, Jie; Liu, Juan; Zhou, Jian-Wei; Wang, Hai-Long; Mo, Kai-Kun; Yan, Yan; Xu, Yun-Bin; Liao, Min; Su, Shuo; Hu, Rong-Liang; Zhou, Ji-Yong

    2016-09-10

    Apoptosis, as an innate antiviral defense, not only functions to limit viral replication by eliminating infected cells, but also contribute to viral dissemination, particularly at the late stages of infection. A highly neurotropic CVS strain of rabies virus induces apoptosis both in vitro and in vivo. However, the detailed mechanism of CVS-mediated neuronal apoptosis is not entirely clear. Here, we show that CVS induces apoptosis through mitochondrial pathway by dissipating mitochondrial membrane potential, release of cytochrome c and AIF. CVS blocks Bax activation at the early stages of infection; while M protein partially targets mitochondria and induces mitochondrial apoptosis at the late stages of infection. The α-helix structure spanning 67-79 amino acids of M protein is essential for mitochondrial targeting and induction of apoptosis. These results suggest that CVS functions on mitochondria to regulate apoptosis at different stages of infection, so as to for viral replication and dissemination. PMID:27426727

  3. Metformin synergistically sensitizes FLT3-ITD-positive acute myeloid leukemia to sorafenib by promoting mTOR-mediated apoptosis and autophagy.

    PubMed

    Wang, Fangfang; Liu, Zuofeng; Zeng, Jisha; Zhu, Hongyan; Li, Jingjing; Cheng, Xiaomin; Jiang, Tao; Zhang, Li; Zhang, Chuanfen; Chen, Tie; Liu, Ting; Jia, Yongqian

    2015-12-01

    Mutations of Fms-like tyrosine kinase 3-internal tandem duplication (FLT3-ITD), accounting for approximately 30% of patients with acute myeloid leukemia (AML), results in poor therapeutic efficacy and short survival. Sorafenib, an oral multikinase inhibitor, can inhibit FLT3 and improve clinical outcome of FLT3 mutated leukemia. Our current studies have shown that, the antidiabetic drug metformin also exerts anti-leukemic effect by activating p-AMPK and synergistically sensitizes FLT3 mutated AML to sorafenib. Both agents suppress cell proliferation in a dose-dependent manner and induce apoptosis via cell cycle arrest, but does not obviously modulate autophagy marker, light chain 3 (LC3). Mechanistically, in the presence of metformin, the anticancer potential of sorafenib, accompanying with increased LC3 levels, is found to be synergistically enhanced with the remarkably reduced protein expression of the mTOR/p70S6K/4EBP1 pathway, while not appreciably altering cell cycle. Overall, these results show metformin in aid of sorafenib may represent a promising and attractive strategy for the treatment of FLT3-ITD mutated AML. PMID:26505133

  4. Oncolytic reovirus preferentially induces apoptosis in KRAS mutant colorectal cancer cells, and synergizes with irinotecan

    PubMed Central

    Maitra, Radhashree; Seetharam, Raviraja; Tesfa, Lydia; Augustine, Titto A.; Klampfer, Lidija; Coffey, Matthew C.; Mariadason, John M.; Goel, Sanjay

    2014-01-01

    Reovirus is a double stranded RNA virus, with an intrinsic preference for replication in KRAS mutant cells. As 45% of human colorectal cancers (CRC) harbor KRAS mutations, we sought to investigate its efficacy in KRAS mutant CRC cells, and examine its impact in combination with the topoisimerase-1 inhibitor, irinotecan. Reovirus efficacy was examined in the KRAS mutant HCT116, and the isogenic KRAS WT Hke3 cell line, and in the non-malignant rat intestinal epithelial cell line. Apoptosis was determined by flow cytometry and TUNEL staining. Combination treatment with reovirus and irintoecan was investigated in 15 CRC cell lines, including the HCT116 p21 isogenic cell lines. Reovirus preferentially induced apoptosis in KRAS mutant HCT116 cells compared to its isogenic KRAS WT derivative, and in KRAS mutant IEC cells. Reovirus showed a greater degree of caspase 3 activation with PARP 1 cleavage, and preferential inhibition of p21 protein expression in KRAS mutant cells. Reovirus synergistically induced growth inhibition when combined with irinotecan. This synergy was lost upon p21 gene knock out. Reovirus preferentially induces apoptosis in KRAS mutant colon cancer cells. Reovirus and irinotecan combination therapy is synergistic, p21 mediated, and represents a novel potential treatment for patients with CRC. PMID:24798549

  5. Oncolytic reovirus preferentially induces apoptosis in KRAS mutant colorectal cancer cells, and synergizes with irinotecan.

    PubMed

    Maitra, Radhashree; Seetharam, Raviraja; Tesfa, Lydia; Augustine, Titto A; Klampfer, Lidija; Coffey, Matthew C; Mariadason, John M; Goel, Sanjay

    2014-05-15

    Reovirus is a double stranded RNA virus, with an intrinsic preference for replication in KRAS mutant cells. As 45% of human colorectal cancers (CRC) harbor KRAS mutations, we sought to investigate its efficacy in KRAS mutant CRC cells, and examine its impact in combination with the topoisimerase-1 inhibitor, irinotecan. Reovirus efficacy was examined in the KRAS mutant HCT116, and the isogenic KRAS WT Hke3 cell line, and in the non-malignant rat intestinal epithelial cell line. Apoptosis was determined by flow cytometry and TUNEL staining. Combination treatment with reovirus and irintoecan was investigated in 15 CRC cell lines, including the HCT116 p21 isogenic cell lines. Reovirus preferentially induced apoptosis in KRAS mutant HCT116 cells compared to its isogenic KRAS WT derivative, and in KRAS mutant IEC cells. Reovirus showed a greater degree of caspase 3 activation with PARP 1 cleavage, and preferential inhibition of p21 protein expression in KRAS mutant cells. Reovirus synergistically induced growth inhibition when combined with irinotecan. This synergy was lost upon p21 gene knock out. Reovirus preferentially induces apoptosis in KRAS mutant colon cancer cells. Reovirus and irinotecan combination therapy is synergistic, p21 mediated, and represents a novel potential treatment for patients with CRC. PMID:24798549

  6. Axl Inhibition Primes Chronic Lymphocytic Leukemia B-Cells to Apoptosis and Show Synergistic/Additive Effects in Combination with BTK inhibitors

    PubMed Central

    Sinha, Sutapa; Boysen, Justin; Nelson, Michael; Secreto, Charla; Warner, Steven L.; Bearss, David J.; Lesnick, Connie; Shanafelt, Tait D.; Kay, Neil E.; Ghosh, Asish K.

    2015-01-01

    Purpose B-cell chronic lymphocytic leukemia (CLL) is an incurable disease despite aggressive therapeutic approaches. We previously found that Axl receptor tyrosine kinase (RTK) plays a critical role in CLL B-cell survival. Here, we explored the possibility of using a high-affinity Axl inhibitor as a single agent or in combination with Bruton’s tyrosine kinase (BTK) inhibitors for future clinical trial to treat CLL patients. Experimental Design Expression/activation status of other members of the TAM (Tyro3, Axl, MER) family of RTKs in CLL B-cells was evaluated. Cells were treated with a high-affinity orally bioavailable Axl inhibitor TP-0903 with or without presence of CLL bone marrow stromal cells (BMSCs). Inhibitory effects of TP-0903 on Axl signaling pathway was also evaluated in CLL B-cells. Finally, cells were exposed to TP-0903 in combination with BTK inhibitors to determine any synergistic/additive effects of the combination. Results CLL B-cells overexpress Tyro3, but not MER. Of interest, Tyro3 remains as constitutively phosphorylated and form a complex with Axl in CLL B-cells. TP-0903 induces massive apoptosis in CLL B-cells with LD50 values of nanomolar ranges. Importantly, CLL BMSCs could not protect the leukemic B-cells from TP-0903 induced apoptosis. A marked reduction of the anti-apoptotic proteins Mcl-1, Bcl-2, XIAP and upregulation of the pro-apoptotic protein BIM in CLL B-cells were detected as a result of Axl inhibition. Finally, combination of TP-0903 with BTK inhibitors augments CLL B-cell apoptosis. Conclusion Administration of TP-0903 either as a single agent or in combination with BTK inhibitors may be effective in treating CLL patients. PMID:25673699

  7. Research Advances on Pathways of Nickel-Induced Apoptosis

    PubMed Central

    Guo, Hongrui; Chen, Lian; Cui, Hengmin; Peng, Xi; Fang, Jing; Zuo, Zhicai; Deng, Junliang; Wang, Xun; Wu, Bangyuan

    2015-01-01

    High concentrations of nickel (Ni) are harmful to humans and animals. Ni targets a number of organs and produces multiple toxic effects. Apoptosis is important in Ni-induced toxicity of the kidneys, liver, nerves, and immune system. Apoptotic pathways mediated by reactive oxygen species (ROS), mitochondria, endoplasmic reticulum (ER), Fas, and c-Myc participate in Ni-induced cell apoptosis. However, the exact mechanism of apoptosis caused by Ni is still unclear. Understanding the mechanism of Ni-induced apoptosis may help in designing measures to prevent Ni toxicity. PMID:26703593

  8. Quercetin-induced apoptosis prevents EBV infection

    PubMed Central

    Lee, Minjung; Son, Myoungki; Ryu, Eunhyun; Shin, Yu Su; Kim, Jong Gwang; Kang, Byung Woog; Sung, Gi-Ho; Cho, Hyosun; Kang, Hyojeung

    2015-01-01

    Epstein-Barr virus (EBV) is a human gamma-1 herpesvirus that establishes a lifelong latency in over 90% of the world's population. During latency, virus exists predominantly as a chromatin-associated, multicopy episome in the nuclei of a variety of tumor cells derived from B cells, T cells, natural killer (NK) cells, and epithelial cells. Licorice is the root of Glycyrrhiza uralensis or G. glabra that has traditionally cultivated in eastern part of Asia. Licorice was reported to have anti-viral, anti-inflammatory, anti-atopic, hepatoprotective, anti-neurodegenerative, anti-tumor, anti-diabetic effects and so forth. Quercetin and isoliquiritigenin are produced from licorice and highly similar in molecular structure. They have diverse bioactive effects such as antiviral activity, anti-asthmatic activity, anti-cancer activity, anti-inflammation activity, monoamine-oxidase inhibitor, and etc. To determine anti-EBV and anti-EBVaGC (Epstein-Barr virus associated gastric carcinoma) effects of licorice, we investigated antitumor and antiviral effects of quercetin and isoliquiritigenin against EBVaGC. Although both quercetin and isoliquiritigenin are cytotoxic to SNU719 cells, quercetin induced more apoptosis in SNU719 cells than isoliquiritigenin, more completely eliminated DNMT1 and DNMT3A expressions than isoliquiritigenin, and more strongly affects the cell cycle progression of SNU719 than isoliquiritigenin. Both quercetin and isoliquiritigenin induce signal transductions to stimulate apoptosis, and induce EBV gene transcription. Quercetin enhances frequency of F promoter use, whereas isoliquiritigenin enhances frequency of Q promoter use. Quercetin reduces EBV latency, whereas isoliquiritigenin increases the latency. Quercetin increases more the EBV progeny production, and inhibits more EBV infection than isoliquiritigenin. These results indicate that quercetin could be a promising candidate for antiviral and antitumor agents against EBV and human gastric carcinoma

  9. Participation of cyclin A in Myc-induced apoptosis.

    PubMed Central

    Hoang, A T; Cohen, K J; Barrett, J F; Bergstrom, D A; Dang, C V

    1994-01-01

    The involvement of c-Myc in cellular proliferation or apoptosis has been linked to differential cyclin gene expression. We observed that in both proliferating cells and cells undergoing apoptosis, cyclin A (but not B, C, D1, and E) mRNA level was elevated in unsynchronized Myc-overexpressing cells when compared with parental Rat1a fibroblasts. We further demonstrated that Zn(2+)-inducible cyclin A expression was sufficient to cause apoptosis. When Myc-induced apoptosis was blocked by coexpression of Bcl-2, the levels of cyclin C, D1, and E mRNAs were also elevated. Thus, while apoptosis induced by c-Myc is associated with an elevated cyclin A mRNA level, protection from apoptosis by coexpressed Bcl-2 is associated with a complementary increase in cyclin C, D1, and E mRNAs. Images PMID:8041712

  10. Granzyme K synergistically potentiates LPS-induced cytokine responses in human monocytes.

    PubMed

    Wensink, Annette C; Kemp, Vera; Fermie, Job; García Laorden, M Isabel; van der Poll, Tom; Hack, C Erik; Bovenschen, Niels

    2014-04-22

    Granzymes are serine proteases released by cytotoxic lymphocytes to induce apoptosis in virus-infected cells and tumor cells. Evidence is emerging that granzymes also play a role in controlling inflammation. Granzyme serum levels are elevated in patients with autoimmune diseases and infections, including sepsis. However, the function of extracellular granzymes in inflammation largely remains unknown. Here, we show that granzyme K (GrK) binds to Gram-negative bacteria and their cell-wall component lipopolysaccharide (LPS). GrK synergistically enhances LPS-induced cytokine release in vitro from primary human monocytes and in vivo in a mouse model of LPS challenge. Intriguingly, these extracellular effects are independent of GrK catalytic activity. GrK disaggregates LPS from micelles and augments LPS-CD14 complex formation, thereby likely boosting monocyte activation by LPS. We conclude that extracellular GrK is an unexpected direct modulator of LPS-TLR4 signaling during the antimicrobial innate immune response. PMID:24711407

  11. Chronic heat-shock treatment driven differentiation induces apoptosis in Leishmania donovani.

    PubMed

    Raina, Puneet; Kaur, Sukhbir

    2006-09-01

    The present study investigates the role of apoptosis in the regulation of cell numbers of Leishmania donovani during the in vitro differentiation of promastigote stage to amastigote stage in axenic conditions. We report that apoptosis is induced in Leishmania donovani due to chronic heat-shock treatment of 37 ( degrees )C that also mediates the differentiation of promastigotes to amastigotes. This is characterized by the fragmentation of DNA, blebbing in the parasite cell membrane, nuclear condensation, formation of preapoptotic bodies and involvement of Ca(++) in the apoptotic process. The flowcytometric analysis shows an early and steep rise in percentage apoptotic nuclei till 48-hour stage of differentiation and then a gradual decline, suggesting synergistic action of Ca(++) ATPase and probably Hsp70. Hsp70 might be rescuing cells from apoptosis in the death signaling pathway. Incubation of the culture with Ca(++) chelator EGTA (1 mM) brings down the percentage of apoptotic nuclei considerably showing thereby that calcium is needed for the process of cell death here that occurs by apoptosis. The survival of the infective individuals appears to be decided by the parasite in the early stages of its differentiation. Our studies show the potential of the physiological temperature of 37 ( degrees )C in inducing apoptosis in Leishmania donovani and the therapeutic use it can be put to. PMID:16718376

  12. Artesunate overcomes drug resistance in multiple myeloma by inducing mitochondrial stress and non-caspase apoptosis

    PubMed Central

    Papanikolaou, Xenofon; Johnson, Sarah; Garg, Tarun; Tian, Erming; Tytarenko, Ruslana; Zhang, Qing; Stein, Caleb; Barlogie, Bart; Epstein, Joshua; Heuck, Christoph

    2014-01-01

    Although novel drugs have contributed immensely to improving outcomes of patients with multiple myeloma (MM), many patients develop drug resistance and ultimately succumb to MM. Here, we show that artesunate, an anti-malarial drug, reliably induces cell death in vitro in naïve as well as drug-resistant MM cells at concentrations shown to be safe in humans. Artesunate induced apoptosis predominantly through the non-caspase mediated pathway by primarily targeting mitochondria and causing outer mitochondrial membrane permeabilization that led to cytosolic and subsequent nuclear translocation of mitochondrial proteins apoptosis inducing factor (AIF) and endonuclease G (EndoG). Nuclear translocation of AIF and EndoG was accompanied by low levels of reactive oxygen species (ROS) and increased mitochondrial production of superoxide. These effects were present before apoptosis was evident and were related to intracellular levels of bivalent iron (Fe+2). Artesunate's unique mechanism probably was at least partially responsible for, its ability to act synergistically with multiple anti-myeloma agents. Our findings suggest that artesunate acts through iron to affect the mitochondria and induce low ROS and non-caspase–mediated apoptosis. Its potency, toxicity profile, and synergism with other drugs make it an intriguing new candidate for MM treatment. PMID:24948357

  13. Platelets induce apoptosis via membrane-bound FasL

    PubMed Central

    Schleicher, Rebecca I.; Reichenbach, Frank; Kraft, Peter; Kumar, Anil; Lescan, Mario; Todt, Franziska; Göbel, Kerstin; Hilgendorf, Ingo; Geisler, Tobias; Bauer, Axel; Olbrich, Marcus; Schaller, Martin; Wesselborg, Sebastian; O’Reilly, Lorraine; Meuth, Sven G.; Schulze-Osthoff, Klaus; Gawaz, Meinrad; Li, Xuri; Kleinschnitz, Christoph; Edlich, Frank

    2015-01-01

    After tissue injury, both wound sealing and apoptosis contribute to restoration of tissue integrity and functionality. Although the role of platelets (PLTs) for wound closure and induction of regenerative processes is well established, the knowledge about their contribution to apoptosis is incomplete. Here, we show that PLTs present the death receptor Fas ligand (FasL) on their surface after activation. Activated PLTs as well as the isolated membrane fraction of activated PLTs but not of resting PLTs induced apoptosis in a dose-dependent manner in primary murine neuronal cells, human neuroblastoma cells, and mouse embryonic fibroblasts. Membrane protein from PLTs lacking membrane-bound FasL (FasL△m/△m) failed to induce apoptosis. Bax/Bak-mediated mitochondrial apoptosis signaling in target cells was not required for PLT-induced cell death, but increased the apoptotic response to PLT-induced Fas signaling. In vivo, PLT depletion significantly reduced apoptosis in a stroke model and an inflammation-independent model of N-methyl-d-aspartic acid-induced retinal apoptosis. Furthermore, experiments using PLT-specific PF4Cre+ FasLfl/fl mice demonstrated a role of PLT-derived FasL for tissue apoptosis. Because apoptosis secondary to injury prevents inflammation, our findings describe a novel mechanism on how PLTs contribute to tissue homeostasis. PMID:26232171

  14. Polo-like kinase 1 inhibition sensitizes neuroblastoma cells for vinca alkaloid-induced apoptosis

    PubMed Central

    Czaplinski, Sebastian; Hugle, Manuela; Stiehl, Valerie; Fulda, Simone

    2016-01-01

    High polo-like kinase 1 (PLK1) expression has been linked to poor outcome in neuroblastoma (NB), indicating that it represents a relevant therapeutic target in this malignancy. Here, we identify a synergistic induction of apoptosis by the PLK1 inhibitor BI 2536 and vinca alkaloids in NB cells. Synergistic drug interaction of BI 2536 together with vincristine (VCR), vinblastine (VBL) or vinorelbine (VNR) is confirmed by calculation of combination index (CI). Also, BI 2536 and VCR act in concert to reduce long-term clonogenic survival. Importantly, BI 2536 significantly enhances the antitumor activity of VCR in an in vivo model of NB. Mechanistically, BI 2536/VCR co-treatment triggers prolonged mitotic arrest, which is necessary for BI 2536/VCR-mediated apoptosis, since pharmacological inhibition of mitotic arrest by the CDK1 inhibitor RO-3306 significantly reduces cell death. Prolonged mitotic arrest leads to phosphorylation-mediated inactivation of BCL-2 and BCL-XL as well as downregulation of MCL-1, since inhibition of mitotic arrest by RO-3306 also prevents phosphorylation of BCL-2 and BCL-XL and MCL-1 downregulation. This inactivation of antiapoptotic BCL-2 proteins promotes activation of BAX and BAK, cleavage of caspase-9 and -3 and caspase-dependent apoptosis. Engagement of the mitochondrial pathway of apoptosis is critically required for BI 2536/VCR-induced apoptosis, since ectopic expression of a non-degradable MCL-1 phospho-mutant, BCL-2 overexpression or BAK knockdown significantly reduce BI 2536/VCR-mediated apoptosis. Thus, PLK1 inhibitors may open new perspectives for chemosensitization of NB. PMID:26046302

  15. Polo-like kinase 1 inhibition sensitizes neuroblastoma cells for vinca alkaloid-induced apoptosis.

    PubMed

    Czaplinski, Sebastian; Hugle, Manuela; Stiehl, Valerie; Fulda, Simone

    2016-02-23

    High polo-like kinase 1 (PLK1) expression has been linked to poor outcome in neuroblastoma (NB), indicating that it represents a relevant therapeutic target in this malignancy. Here, we identify a synergistic induction of apoptosis by the PLK1 inhibitor BI 2536 and vinca alkaloids in NB cells. Synergistic drug interaction of BI 2536 together with vincristine (VCR), vinblastine (VBL) or vinorelbine (VNR) is confirmed by calculation of combination index (CI). Also, BI 2536 and VCR act in concert to reduce long-term clonogenic survival. Importantly, BI 2536 significantly enhances the antitumor activity of VCR in an in vivo model of NB. Mechanistically, BI 2536/VCR co-treatment triggers prolonged mitotic arrest, which is necessary for BI 2536/VCR-mediated apoptosis, since pharmacological inhibition of mitotic arrest by the CDK1 inhibitor RO-3306 significantly reduces cell death. Prolonged mitotic arrest leads to phosphorylation-mediated inactivation of BCL-2 and BCL-XL as well as downregulation of MCL-1, since inhibition of mitotic arrest by RO-3306 also prevents phosphorylation of BCL-2 and BCL-XL and MCL-1 downregulation. This inactivation of antiapoptotic BCL-2 proteins promotes activation of BAX and BAK, cleavage of caspase-9 and -3 and caspase-dependent apoptosis. Engagement of the mitochondrial pathway of apoptosis is critically required for BI 2536/VCR-induced apoptosis, since ectopic expression of a non-degradable MCL-1 phospho-mutant, BCL-2 overexpression or BAK knockdown significantly reduce BI 2536/VCR-mediated apoptosis. Thus, PLK1 inhibitors may open new perspectives for chemosensitization of NB. PMID:26046302

  16. Piperlongumine Induces Apoptosis and Synergizes with Cisplatin or Paclitaxel in Human Ovarian Cancer Cells

    PubMed Central

    Chen, Xiu-Xiu; Wang, Huan; Jiang, Qi-Wei; Pan, Shi-Shi; Qiu, Jian-Ge; Mei, Xiao-Long; Xue, You-Qiu; Qin, Wu-Ming; Zheng, Fei-Yun; Yan, Xiao-Jian

    2014-01-01

    Piperlongumine (PL), a natural alkaloid from Piper longum L., possesses the highly selective and effective anticancer property. However, the effect of PL on ovarian cancer cells is still unknown. In this study, we firstly demonstrate that PL selectively inhibited cell growth of human ovarian cancer cells. Furthermore, PL notably induced cell apoptosis, G2/M phase arrest, and accumulation of the intracellular reactive oxidative species (ROS) in a dose- and time-dependent manner. Pretreatment with antioxidant N-acety-L-cysteine could totally reverse the PL-induced ROS accumulation and cell apoptosis. In addition, low dose of PL/cisplatin or paclitaxel combination therapies had a synergistic antigrowth effect on human ovarian cancer cells. Collectively, our study provides new therapeutic potential of PL on human ovarian cancer. PMID:24895529

  17. Piperlongumine induces apoptosis and synergizes with cisplatin or paclitaxel in human ovarian cancer cells.

    PubMed

    Gong, Li-Hua; Chen, Xiu-Xiu; Wang, Huan; Jiang, Qi-Wei; Pan, Shi-Shi; Qiu, Jian-Ge; Mei, Xiao-Long; Xue, You-Qiu; Qin, Wu-Ming; Zheng, Fei-Yun; Shi, Zhi; Yan, Xiao-Jian

    2014-01-01

    Piperlongumine (PL), a natural alkaloid from Piper longum L., possesses the highly selective and effective anticancer property. However, the effect of PL on ovarian cancer cells is still unknown. In this study, we firstly demonstrate that PL selectively inhibited cell growth of human ovarian cancer cells. Furthermore, PL notably induced cell apoptosis, G2/M phase arrest, and accumulation of the intracellular reactive oxidative species (ROS) in a dose- and time-dependent manner. Pretreatment with antioxidant N-acety-L-cysteine could totally reverse the PL-induced ROS accumulation and cell apoptosis. In addition, low dose of PL/cisplatin or paclitaxel combination therapies had a synergistic antigrowth effect on human ovarian cancer cells. Collectively, our study provides new therapeutic potential of PL on human ovarian cancer. PMID:24895529

  18. Chemosensitizing effect of podophyllotoxin acetate on topoisomerase inhibitors leads to synergistic enhancement of lung cancer cell apoptosis.

    PubMed

    Hong, Wan Gi; Cho, Jeong Hyun; Hwang, Sang-Gu; Lee, Eunah; Lee, Jaeseok; Kim, Jong-Il; Um, Hong-Duck; Park, Jong Kuk

    2016-06-01

    Podophyllotoxin acetate (PA) acts as a radiosensitizer against non-small cell lung cancer (NSCLC) in vitro and in vivo. In this study, we examined its potential role as a chemosensitizer in conjunction with the topoisomerase inhibitors etoposide (Eto) and camptothecin (Cpt). The effects of combinations of PA and Eto/Cpt were examined with CompuSyn software in two NSCLC cell lines, A549 and NCI-H1299. Combination index (CI) values indicated synergistic effects of PA and the topoisomerase inhibitors. The intracellular mechanism underlying synergism was further determined using propidium iodide uptake, immunoblotting and electrophoretic mobility shift assay (EMSA). Combination of PA with Eto/Cpt promoted disruption of the dynamics of actin filaments, leading to subsequent enhancement of apoptotic cell death via induction of caspase-3, -8, and -9, accompanied by increased phosphorylation of p38. Conversely, suppression of p38 phosphorylation blocked the apoptotic effect of the drug combinations. Notably, CREB-1, a transcription factor, was constitutively activated in both cell types, and synergistically inhibited upon combination treatment. Our results collectively indicate that PA functions as a chemosensitizer by enhancing apoptosis through activation of the p38/caspase axis and suppression of CREB-1. PMID:27035096

  19. Chemosensitizing effect of podophyllotoxin acetate on topoisomerase inhibitors leads to synergistic enhancement of lung cancer cell apoptosis

    PubMed Central

    HONG, WAN GI; CHO, JEONG HYUN; HWANG, SANG-GU; LEE, EUNAH; LEE, JAESEOK; KIM, JONG-IL; UM, HONG-DUCK; PARK, JONG KUK

    2016-01-01

    Podophyllotoxin acetate (PA) acts as a radiosensitizer against non-small cell lung cancer (NSCLC) in vitro and in vivo. In this study, we examined its potential role as a chemosensitizer in conjunction with the topoisomerase inhibitors etoposide (Eto) and camptothecin (Cpt). The effects of combinations of PA and Eto/Cpt were examined with CompuSyn software in two NSCLC cell lines, A549 and NCI-H1299. Combination index (CI) values indicated synergistic effects of PA and the topoisomerase inhibitors. The intracellular mechanism underlying synergism was further determined using propidium iodide uptake, immunoblotting and electrophoretic mobility shift assay (EMSA). Combination of PA with Eto/Cpt promoted disruption of the dynamics of actin filaments, leading to subsequent enhancement of apoptotic cell death via induction of caspase-3, -8, and -9, accompanied by increased phosphorylation of p38. Conversely, suppression of p38 phosphorylation blocked the apoptotic effect of the drug combinations. Notably, CREB-1, a transcription factor, was constitutively activated in both cell types, and synergistically inhibited upon combination treatment. Our results collectively indicate that PA functions as a chemosensitizer by enhancing apoptosis through activation of the p38/caspase axis and suppression of CREB-1. PMID:27035096

  20. Interferon-α and cyclooxygenase-2 inhibitor cooperatively mediates TRAIL-induced apoptosis in hepatocellular carcinoma

    SciTech Connect

    Zuo, Chaohui; Qiu, Xiaoxin; Liu, Nianli; Yang, Darong; Xia, Man; Liu, Jingshi; Wang, Xiaohong; and others

    2015-05-01

    Hepatocellular carcinoma (HCC) is a leading cause of cancer-related mortality worldwide. Interferon-alpha (IFN-α) has recently been recognized to harbor therapeutic potential in the prevention and treatment of HCC, but it remains controversial as to whether IFN-α exerts direct cytotoxicity against HCC. Cyclooxygenase-2 (COX-2) is overexpressed in HCC and is considered to play a role in hepatocarcinogenesis. Therefore, we aimed to elucidate the combined effect of a COX-2 inhibitor, celecoxib, and IFN-α on in vitro growth suppression of HCC using the hepatoma cell line HLCZ01 and the in vivo nude mouse xenotransplantation model using HLCZ01 cells. Treatment with celecoxib and IFN-α synergistically inhibited cell proliferation in a dose- and time-dependent manner. Apoptosis was identified by 4',6-diamidino-2-phenylindole dihydrochloride and fluorescent staining. IFN-α upregulated the expression of TRAIL, while celecoxib increased the expression of TRAIL receptors. The combined regimen with celecoxib and IFN-α reduced the growth of xenotransplanted HCCs in nude mice. The regulation of IFN-α- and COX-2 inhibitor-induced cell death is impaired in a subset of TRAIL-resistant cells. The molecular mechanisms of HCC cells resistant to TRAIL-induced apoptosis were explored using molecular biological and immunological methods. Interferon-α and the COX-2 inhibitor celecoxib synergistically increased TRAIL-induced apoptosis in hepatocellular carcinoma. These data suggest that IFN-α and celecoxib may offer a novel role with important implications in designing new therapeutics for TRAIL-resistant tumors. - Highlights: ●The cytotoxic effect of TRAIL on a developed HCC HLCZ01 cells infected with HBV. ●IFN-α and celecoxib induced apoptosis in HLCZ01 cells infected with HBV. ●The combined regime reduced the growth of xenotransplanted HCCs in nude mice model.

  1. PRMT6 mediates CSE induced inflammation and apoptosis.

    PubMed

    Kang, Naixing; Chen, Ping; Chen, Yan; Zeng, Huihui; He, Xue; Zhu, Yingqun

    2015-01-01

    Cigarette smoke extract (CSE) induces apoptosis and inflammation, but the mechanism is unknown. Arginine methyltransferase (PRMT6) catalyzes the asymmetric di-methylation of histone H3 arginine 2 (H3R2me2a) to control global level transcription. We hypothesized that PRMT6 mediates CSE induced apoptosis and inflammation through H3R2me2a. The apoptosis after CSE treatment in human umbilical vein endothelial cells (HUVECs) was fully measured with real-time reverse transcription PCR, western blotting and Annexin-V staining. Meanwhile, the inflammation in HUVECs after CSE exposure was detected with real-time reverse transcription PCR, western blotting and ELISA. CSE treatment promoted apoptosis and inflammation in HUVECs, coinciding with the decreased protein abundance of PRMT6. Meanwhile, HUVECs transfected with PRMT6 expressing plasmid inhibited the CSE-induced apoptosis and inflammation. Also, the inhibition of PRMT6 promoted the apoptosis and inflammation in HUVECs induced by CSE. Notably, H3R2me2a was associated with the modulation of PRMT6 in CSE induced apoptosis and inflammation in HUVECs. In conclusion, PRMT6 mediates CSE induced apoptosis and inflammation through H3R2me2a in HUVECs. PMID:25481537

  2. Role of PUMA in methamphetamine-induced neuronal apoptosis.

    PubMed

    Chen, Chuanxiang; Qincao, Litao; Xu, Jingtao; Du, Sihao; Huang, Enping; Liu, Chao; Lin, Zhoumeng; Xie, Wei-Bing; Wang, Huijun

    2016-01-01

    Exposure to methamphetamine (METH), a widely used illicit drug, has been shown to cause neuron apoptosis. p53 upregulated modulator of apoptosis (PUMA) is a key mediator in neuronal apoptosis. This study aimed to examine the effects of PUMA in METH-induced neuronal apoptosis. We determined PUMA protein expression in PC12 cells and SH-SY5Y cells after METH exposure using western blot. We also observed the effect of METH on neuronal apoptosis after silencing PUMA expression with siRNA using TUNEL staining and flow cytometry. Additionally, to investigate possible mechanisms of METH-induced PUMA-mediated neuronal apoptosis, we measured the protein expression of apoptotic markers, including cleaved caspase-3, cleaved PARP, Bax, B-cell leukemia/lymphoma-2 (Bcl-2) and cytochrome c (cyto c), after METH treatment with or without PUMA knockdown. Results showed that METH exposure induced cell apoptosis, increased PUMA protein levels, activated caspase-3 and PARP, elevated Bax and reduced Bcl-2 expression, as well as increased the release of cyto c from mitochondria to the cytoplasm in both PC12 and SH-SY5Y cells. All these effects were attenuated or reversed after silencing PUMA. A schematic depicting the role of PUMA in METH-induced mitochondrial apoptotic pathway was proposed. Our results suggest that PUMA plays an important role in METH-triggered apoptosis and it may be a potential target for ameliorating neuronal injury and apoptosis caused by METH. PMID:26524635

  3. Synergistic anti-oral cancer effects of UVC and methanolic extracts of Cryptocarya concinna roots via apoptosis, oxidative stress and DNA damage.

    PubMed

    Chang, Hsueh-Wei; Tang, Jen-Yang; Yen, Ching-Yu; Chang, Hsun-Shuo; Huang, Hurng-Wern; Chung, Yi-An; Chen, Ih-Sheng; Huang, Ming-Yii

    2016-05-01

    Purpose Radiation combined with natural products may improve the radiosensitivity of cancer cells. This study investigated the potential of a combined modality treatment with Ultraviolet C (UVC; wavelength range 200-280 nm) and our previously identified anti-oral cancer agent (methanolic extracts of Cryptocarya concinna roots; MECCrt) in oral cancer cells. Materials and methods The mechanism of the possible synergy of UVC and MECCrt was explored in terms of cell viability, cell cycle, apoptosis, reactive oxygen species (ROS), mitochondrial membrane potential (MitoMP), and DNA damage analyses. Results In cell viability (%) at 24 h treatment, the low doses of UVC (14 J/m(2)) and MECCrt (10 μg/ml) resulted in slight damage to human oral cancer Ca9-22 cells (83.2 and 80.4) but was less harmful to human oral normal HGF-1 cells (93.4 and 91.8, respectively). The combined treatment of UVC and MECCrt (UVC/MECCrt) had a lower viability (54.5%) than UVC or MECCrt alone in Ca9-22 cells but no showed significant change in HGF-1 cells. In Ca9-22 cells, the expression of flow cytometry-based apoptosis (sub-G1 phase, annexin V, and pancaspase assays) was significantly higher in UVC/MECCrt than in UVC or MECCrt alone (p < 0.0001). Using flow cytometry, intracellular ROS levels of UVC/MECCrt and MECCrt alone were higher than for UVC alone. MitoMP change and H2A histone family member X (γH2AX; H2AFX)-based DNA damage were synergistically inhibited and induced by MECCrt/UVC compared to its single treatment in Ca9-22 cells, respectively. Conclusion UVC plus MECCrt treatment had selective killing and synergistic anti-proliferative effects against oral cancer cells involving apoptosis, oxidative stress, and DNA damage. This combination therapy appears to have a great clinical potential against oral cancer cells. PMID:26887975

  4. Marine Drugs Regulating Apoptosis Induced by Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand (TRAIL)

    PubMed Central

    Elmallah, Mohammed I. Y.; Micheau, Olivier

    2015-01-01

    Marine biomass diversity is a tremendous source of potential anticancer compounds. Several natural marine products have been described to restore tumor cell sensitivity to TNF-related apoptosis inducing ligand (TRAIL)-induced cell death. TRAIL is involved during tumor immune surveillance. Its selectivity for cancer cells has attracted much attention in oncology. This review aims at discussing the main mechanisms by which TRAIL signaling is regulated and presenting how marine bioactive compounds have been found, so far, to overcome TRAIL resistance in tumor cells. PMID:26580630

  5. Retinoids induce Nur77-dependent apoptosis in mouse thymocytes.

    PubMed

    Kiss, Beáta; Tóth, Katalin; Sarang, Zsolt; Garabuczi, Éva; Szondy, Zsuzsa

    2015-03-01

    Nur77 is a transcription factor, which plays a determinant role in mediating T cell receptor-induced cell death of thymocytes. In addition to regulation of transcription, Nur77 contributes to apoptosis induction by targeting mitochondria, where it can convert Bcl-2, an anti-apoptotic protein into a proapoptotic molecule. Previous studies have demonstrated that retinoids are actively produced in the mouse thymus and can induce a transcription-dependent apoptosis in mouse thymocytes. Here we show that retinoic acids induce the expression of Nur77, and retinoid-induced apoptosis is completely dependent on Nur77, as retinoids were unable to induce apoptosis in Nur77 null thymocytes. In wild-type thymocytes retinoids induced enhanced expression of the apoptosis-related genes FasL, TRAIL, NDG-1, Gpr65 and Bid, all of them in a Nur77-dependent manner. The combined action of these proteins led to Caspase 8-dependent Bid cleavage in the mitochondria. In addition, we could demonstrate the Nur77-dependent induction of STAT1 leading to enhanced Bim expression, and the mitochondrial translocation of Nur77 leading to the exposure of the Bcl-2/BH3 domain. The retinoid-induced apoptosis was dependent on both Caspase 8 and STAT1. Our data together indicate that retinoids induce a Nur77-dependent cell death program in thymocytes activating the mitochondrial pathway of apoptosis. PMID:25576519

  6. Zinc has ambiguous effects on chromium (VI)-induced oxidative stress and apoptosis.

    PubMed

    Rudolf, Emil; Cervinka, Miroslav; Cerman, Jaroslav

    2005-01-01

    Zinc is an important cellular antioxidant. We investigated its role in chromium-induced oxidative stress and apoptosis in human tumor cell line Hep-2. The measured parameters included intracellular labile zinc content (Zinquin-E fluorescence), cell viability (WST-1 assay), oxidative stress (spectrophotometry), mitochondrial potential (flow cytometry), caspase-3 activity, and PARP cleavage (immunofluorescence). We found that Hep-2 cells contain abundant labile zinc stores that may be depleted by the ionophore TPEN or increased by external zinc supplementation. Chromium (VI)-induced cytotoxicity and apoptosis were enhanced in zinc-depleted cells after 24 h, in particular at chromium (VI) concentrations of 50 and 150 micromol/l. On the other hand, elevated levels of labile zinc were able to protect against apoptosis induced by 10 micromol/l chromium (VI) but at higher chromium (VI) concentrations (50 and 150 micromol/l) acted synergistically, significantly enhancing oxidative stress and the course of apoptosis, possibly through oxidative stress and mitochondrial damage. PMID:15966574

  7. Upregulation of PTEN involved in scorpion venom-induced apoptosis in a lymphoma cell line.

    PubMed

    Gao, Fang; Li, Hao; Chen, Ya-Dong; Yu, Xiao-Ning; Wang, Ran; Chen, Xue-Liang

    2009-04-01

    We investigated whether the venom of the scorpion Buthus martensii Karsch (BmK) inhibited growth of human lymphoma cells by inducing apoptosis, and studied possible signal pathways involved in this cell death. BmK venom selectively reduced the viability of Raji and Jurkat cells, and had low toxicity to human peripheral blood lymphocytes. Flow cytometry showed that BmK venom-induced apoptosis and G(0)/G(1) cell cycle arrest in Raji and Jurkat cells. In Raji cells, BmK venom upregulated the expression of PTEN accompanied by decreased levels of Akt and Bad phosphorylation. Treatment with BmK venom and LY294002 (an inhibitor of Akt) synergistically enhanced apoptosis. The expression of p27 was increased in both PTEN-positive Raji and PTEN-negative Jurkat cells exposed to BmK venom. The results indicate that key regulators in BmK venom-induced apoptosis are PTEN, acting through downregulation of the PI3K/Akt signal pathway, in Raji cells and p27 in Jurkat cells. PMID:19373662

  8. Mitochondrion-mediated apoptosis induced by photofrin-PDT

    NASA Astrophysics Data System (ADS)

    Wu, Yunxia; Xing, Da

    2007-05-01

    Apoptosis is an important cellular event that plays a key role in pathogeny and therapy of many diseases. The mechanisms of the initiation and regulation of PDT-induced apoptosis are complex. Some PDT-associated apoptosis pathways involved plasma membrane death receptors, mitochondria, lysosomes and endoplasmic reticulum (ER). In order to determine the apoptosis pathway induced by Photofrin-PDT, we used fluorescence resonance energy transfer (FRET) technique and probe SCAT3 to monitor the dynamics of caspase-3 activation after PDT treatment and also measured caspase-8 activity. With laser scanning confocal microscopy, we found that Photofrin were localized primarily in mitochondria, the primary targets of Photofrin-PDT. Formation of mitochondrial reactive oxygen species (ROS) was detected within minutes after PDT treatment. This was followed by mitochondrial membrane potential (ΔΨm), cytochrome c release, caspase-9 activity, caspase-3 activity and apoptosis. After PDT treatment, caspase-3 was activated rapidly while caspase-8 remained inactivated. Our results indicated that PDT-induced apoptosis was initiated from mitochondria pathway and independent of caspase-8 activation. The activation of caspase-3 by PDT started 20 minutes after treatment and completed in about 15 minutes. PDT-induced apoptosis is directly initiated from mitochondria pathway and not involved in the death receptors-dependent pathway. Our results demonstrated that FRET could be an effective tool to determine PDT-induced apoptosis and other cell death mechanism.

  9. Cyclosporine A and palmitic acid treatment synergistically induce cytotoxicity in HepG2 cells

    SciTech Connect

    Luo, Yi Rana, Payal; Will, Yvonne

    2012-06-01

    Immunosuppressant cyclosporine A (CsA) treatment can cause severe side effects. Patients taking immunosuppressant after organ transplantation often display hyperlipidemia and obesity. Elevated levels of free fatty acids have been linked to the etiology of metabolic syndromes, nonalcoholic fatty liver and steatohepatitis. The contribution of free fatty acids to CsA-induced toxicity is not known. In this study we explored the effect of palmitic acid on CsA-induced toxicity in HepG2 cells. CsA by itself at therapeutic exposure levels did not induce detectible cytotoxicity in HepG2 cells. Co-treatment of palmitic acid and CsA resulted in a dose dependent increase in cytotoxicity, suggesting that fatty acid could sensitize cells to CsA-induced cytotoxicity at the therapeutic doses of CsA. A synergized induction of caspase-3/7 activity was also observed, indicating that apoptosis may contribute to the cytotoxicity. We demonstrated that CsA reduced cellular oxygen consumption which was further exacerbated by palmitic acid, implicating that impaired mitochondrial respiration might be an underlying mechanism for the enhanced toxicity. Inhibition of c-Jun N-terminal kinase (JNK) attenuated palmitic acid and CsA induced toxicity, suggesting that JNK activation plays an important role in mediating the enhanced palmitic acid/CsA-induced toxicity. Our data suggest that elevated FFA levels, especially saturated FFA such as palmitic acid, may be predisposing factors for CsA toxicity, and patients with underlying diseases that would elevate free fatty acids may be susceptible to CsA-induced toxicity. Furthermore, hyperlipidemia/obesity resulting from immunosuppressive therapy may aggravate CsA-induced toxicity and worsen the outcome in transplant patients. -- Highlights: ► Palmitic acid and cyclosporine (CsA) synergistically increased cytotoxicity. ► The impairment of mitochondrial functions may contribute to the enhanced toxicity. ► Inhibition of JNK activity attenuated

  10. Trauma patients’ elevated Tumor Necrosis Related Apoptosis Inducing Ligand (TRAIL) contributes to increased T cell apoptosis

    PubMed Central

    Bandyopadhyay, Gautam; Bankey, Paul E.; Miller-Graziano, Carol L.

    2012-01-01

    Immunosuppression resulting from excessive post-trauma apoptosis of hyperactivated Tcells is controversial. TRAIL mediated Tcell apoptosis decreases highly activated Tcells’ responses. Caspase-10, a particular TRAIL target, was increased in trauma patients’ Tcells with concomitantly elevated plasma TRAIL levels. These patients’ Tcells developed anergy, implicating increased TRAIL-mediated Tcell apoptosis in post-trauma Tcell anergy. Control Tcells cultured with patients’ sera containing high TRAIL levels increased their Caspase-10 activity and apoptosis. Stimulated primary Tcells are TRAIL apoptosis resistant. Increased plasma Thrombospondin-1 and Tcell expression of CD47, a Thrombospondin-1 receptor, preceded patients’ Tcell anergy. CD47 triggering of Tcells increased their sensitivity to TRAIL-induced apoptosis. Augmentation of Tcell TRAIL-induced apoptosis was secondary to CD47 triggered activation of the Src homology-containing phosphatase-1(SHP-1) and was partially blocked by a SHP-1 inhibitor. We suggest that combined post-trauma CD47 triggering, SHP-1 mediated NFκB suppression, and elevated TRAIL levels increase patients’ CD47 expressing Tcell apoptosis, thus contributing to subsequent Tcell anergy. PMID:22926077

  11. UXT plays dual opposing roles on SARM-induced apoptosis.

    PubMed

    Sethurathinam, Shalini; Singh, Laishram Pradeepkumar; Panneerselvam, Porkodi; Byrne, Bernadette; Ding, Jeak Ling

    2013-10-11

    Apoptosis is a vital defense mechanism for the clearance of infected cells. Ubiquitously expressed transcript (UXT), which exists in two isoforms (V1 and V2), interact with both apoptotic and cellular proteins. By yeast two-hybrid analysis, we found that UXT interacts with SARM (sterile α and HEAT armadillo motif-containing protein). Since SARM is a TLR adaptor which induces intrinsic apoptosis following immune activation, we were prompted to query whether UXT and SARM might co-regulate apoptosis. We found that the UXT isoforms elicit dual opposing regulatory effects on SARM-induced apoptosis; while UXT V1, co-expressed with SARM, caused a reduction in caspase 8 activity, UXT V2 strongly increased caspase 8 activity and enhanced SARM-induced apoptosis by activating the extrinsic pathway and depolarizing the mitochondria. PMID:24021647

  12. The ER stress inducer DMC enhances TRAIL-induced apoptosis in glioblastoma.

    PubMed

    van Roosmalen, Ingrid A M; Reis, Carlos R; Setroikromo, Rita; Yuvaraj, Saravanan; Joseph, Justin V; Tepper, Pieter G; Kruyt, Frank A E; Quax, Wim J

    2014-01-01

    cells. In A172 cells, sub-toxic concentrations of DMC greatly potentiated TRAIL-induced apoptosis. Furthermore, DMC strongly reduced survivin expression in A172 and U87 cells and silencing of this anti-apoptotic protein partially sensitized cells to TRAIL-induced apoptosis. Our findings corroborate that DMC is a promising agent against GBM, and uncovers a potential synergistic cooperation with TRAIL in this highly malignant cancer. PMID:26331107

  13. TRPV1 receptors mediate particulate matter-induced apoptosis.

    PubMed

    Agopyan, N; Head, J; Yu, S; Simon, S A

    2004-03-01

    Exposure to airborne particulate matter (PM) is a world-wide health problem mainly because it produces adverse cardiovascular and respiratory effects that frequently result in morbidity. Despite many years of epidemiological and basic research, the mechanisms underlying PM toxicity remain largely unknown. To understand some of these mechanisms, we measured PM-induced apoptosis and necrosis in normal human airway epithelial cells and sensory neurons from both wild-type mice and mice lacking TRPV1 receptors using Alexa Fluor 488-conjugated annexin V and propidium iodide labeling, respectively. Exposure of environmental PMs containing residual oil fly ash and ash from Mount St. Helens was found to induce apoptosis, but not necrosis, as a consequence of sustained calcium influx through TRPV1 receptors. Apoptosis was completely prevented by inhibiting TRPV1 receptors with capsazepine or by removing extracellular calcium or in sensory neurons from TRPV1(-/-) mice. Binding of either one of the PMs to the cell membrane induced a capsazepine-sensitive increase in cAMP. PM-induced apoptosis was augmented upon the inhibition of PKA. PKA inhibition on its own also induced apoptosis, thereby suggesting that this pathway may be endogenously protective against apoptosis. In summary, it was found that inhibiting TRPV1 receptors prevents PM-induced apoptosis, thereby providing a potential mechanism to reduce their toxicity. PMID:14633515

  14. Synergistic protection of N-acetylcysteine and ascorbic acid 2-phosphate on human mesenchymal stem cells against mitoptosis, necroptosis and apoptosis.

    PubMed

    Li, Chia-Jung; Sun, Li-Yi; Pang, Cheng-Yoong

    2015-01-01

    Human mesenchymal stem cells (hMSCs) contribute to ischemic tissue repair, regeneration, and possess ability to self-renew. However, poor viability of transplanted hMSCs within ischemic tissues has limited its therapeutic efficiency. Therefore, it is urgent to explore new method to improve the viability of the grafted cells. By using a systematic analysis, we reveal the mechanism of synergistic protection of N-acetylcysteine (NAC) and ascorbic acid 2-phosphate (AAP) on hMSCs that were under H2O2-induced oxidative stress. The combined treatment of NAC and AAP (NAC/AAP) reduces reactive oxygen species (ROS) generation, stabilizes mitochondrial membrane potential and decreases mitochondrial fission/fragmentation due to oxidative stress. Mitochondrial fission/fragmentation is a major prologue of mitoptosis. NAC/AAP prevents apoptotic cell death via decreasing the activation of BAX, increasing the expression of BCL2, and reducing cytochrome c release from mitochondria that might lead to the activation of caspase cascade. Stabilization of mitochondria also prevents the release of AIF, and its nuclear translocation which may activate necroptosis via H2AX pathway. The decreasing of mitoptosis is further studied by MicroP image analysis, and is associated with decreased activation of Drp1. In conclusion, NAC/AAP protects mitochondria from H2O2-induced oxidative stress and rescues hMSCs from mitoptosis, necroptosis and apoptosis. PMID:25909282

  15. Characterization of radiation-induced Apoptosis in rodent cell lines

    SciTech Connect

    Guo, Min; Chen, Changhu; Ling, C.C.

    1997-03-01

    For REC:myc(ch1), Rat1 and Rat1:myc{sub b} cells, we determined the events in the development of radiation-induced apoptosis to be in the following order: cell division followed by chromatin condensation, membrane blebbing, loss of adhesion and the uptake of vital dye. Experimental data which were obtained using {sup 4}He ions of well defined energies and which compared the dependence of apoptosis and clonogenic survival on {sup 4}He range strongly suggested that in our cells both apoptosis and loss of clonogenic survival resulted from radiation damage to the cell nucleus. Corroboratory evidence was that BrdU incorporation sensitized these cells to radiation-induced apoptosis. Comparing the dose response for apoptosis and the clonogenic survival curves for Rat1 and Rat1:myc{sub b} cells, we concluded that radiation-induced cell inactivation as assayed by clonogenic survival, and that a modified linear-quadratic model, proposed previously, modeled such a contribution effectively. In the same context, the selective increase in radiation-induced apoptosis. Comparing the dose response for apoptosis and the clonogenic survival curves for Rat1 and Rat1:myc{sub b} cells, we concluded that radiation-induced apoptosis contributed to the overall radiation-induced cell inactivation as assayed by clonogenic survival, and that a modified linear-quadratic model, proposed previously, modeled such a contribution effectively. In the same context, the selective increase in radiation-induced apoptosis during late S and G{sub 2} phases reduced the relative radioresistance observed for clonogenic survival during late S and G{sub 2} phases. 30 refs., 8 figs.

  16. Modulation of Radiation-Induced Apoptosis by Thiolamines

    NASA Technical Reports Server (NTRS)

    Warters, R. L.; Roberts, J. C.; Wilmore, B. H.; Kelley, L. L.

    1997-01-01

    Exposure to the thiolamine radioprotector N-(2-mercaptoethyl)-1,3-propanediamine (WR-1065) induced apoptosis in the mouse TB8-3 hybridoma after 60-minute (LD(sub50) = 4.5mM) or during a 20-hour (LD(sub50) = 0.15 mM) exposure. In contrast, a 20-hour exposure to 17 mM L-cysteine or 10 mM cysteamine was required to induce 50 percent apoptosis within 20 hours. Apoptosis was not induced by either a 60-minute or 20-hour exposure to 10 mM of the thiazolidime prodrugs ribose-cysteine (RibCys) or ribose-cysteamine (RibCyst). Thiolamine-induced apoptosis appeared to be a p53-independent process since it was induced by WR-1065 exposure in human HL60 cells. Exposure to WR-1065 (4mM for 15 minutes) or cysteine (10mM for 60 minutes) before and during irradiation protected cells against the induction of both DNA double-strand breaks and apoptosis, while exposure to RibCys (10 mM for 3 hours) did not. Treatment with either WR-1065, cysteine, RibCys or RibCyst for 60 minutes beginning 60 minutes after irradiation did not affect the level of radiation-induced apoptosis. In contrast, treatment with either cysteine, cysteamine or RibCys for 20 hours beginning 60 minutes after irradiation enhanced radiation-induced apoptosis. Similar experiments could not be conducted with WR-1065 because of its extreme toxicity. Our results indicate that thiolamine enhancement of radiation-induced apoptosis is not involved in their previously reported capacity to reduce radiation-induced mutations.

  17. Actinobacillus actinomycetemcomitans induces apoptosis in human monocytic THP-1 cells.

    PubMed

    Kato, Satsuki; Sugimura, Norihiko; Nakashima, Keisuke; Nishihara, Tatsuji; Kowashi, Yusuke

    2005-03-01

    It has previously been reported that the murine macrophage cell line J774.1 and the human oral epithelial cell line KB undergo apoptosis as a result of Actinobacillus actinomycetemcomitans infection. Recent studies have demonstrated that apoptosis regulation is modulated by multiple phosphorylation of several different protein kinases, including the major subtypes of the mitogen-activated protein kinase (MAPK) family. The MAPK family promotes cell survival and/or proliferation in response to growth factor stimulation, or apoptosis in response to various stress stimuli. The primary objective of the present investigation was to clarify whether human immune cells undergo apoptosis following A. actinomycetemcomitans infection and, if so, to establish the involvement of the MAPK family. Human monocytic THP-1 cells were infected with A. actinomycetemcomitans in microtubes. Lactate dehydrogenase release into the culture supernatant and DNA fragmentation in the cells were monitored. DNA fragmentation was also identified by agarose gel electrophoresis. Cell death following A. actinomycetemcomitans infection occurred by apoptosis, shown by an increase in the proportion of fragmented DNA and the typical ladder pattern of DNA fragmentation indicative of apoptosis. Furthermore, p38 MAPK activity and tumour necrosis factor alpha (TNF-alpha) levels increased following A. actinomycetemcomitans infection. In contrast, cell death and TNF-alpha levels in infected cells decreased upon addition of a p38 inhibitor or an anti-TNF-alpha antibody. However, exogenous TNF-alpha could not induce apoptosis in uninfected THP-1 cells. Interestingly, p38 MAPK activity diminished in the presence of anti-TNF-alpha antibody. These findings indicated that A. actinomycetemcomitans infection induces apoptosis in THP-1 cells and that p38 MAPK activity is directly involved in apoptosis. TNF-alpha may play an indirect role in apoptosis via enhanced p38 MAPK activity. A. actinomycetemcomitans-induced

  18. Preventive effects of bicarbonate on cerivastatin-induced apoptosis.

    PubMed

    Kobayashi, Masaki; Kaido, Fumie; Kagawa, Toshiki; Itagaki, Shirou; Hirano, Takeshi; Iseki, Ken

    2007-08-16

    Although HMG-CoA reductase inhibitors such as statins are the most widely used cholesterol-lowering agents, there is a risk of myopathy or rhabdmyolysis occurring in patients taking these drugs. It has been reported that a number of lipophilic statins cause apoptosis in various cells, but it is still not clear whether intracellular acidification is involved in statin-induced apoptosis. There have been few studies aimed at identifying compounds that suppress statin-induced myotoxicity. In the present study, we examined the relationship between cerivastatin-induced apoptosis and intracellular acidification and the effect of bicarbonate on cerivastatin-induced apoptosis using an RD cell line as a model of in vitro skeletal muscle. Cerivastatin reduced the number of viable cells and caused dramatic morphological changes and DNA fragmentation in a concentration-dependent manner. Moreover, cerivastatin-induced apoptosis was associated with intracellular acidification and caspase-9 and -3/7 activation. On the other hand, bicarbonate suppressed cerivastatin-induced pH alteration, caspase activation, morphological change and reduction of cell viability. Accordingly, bicarbonate suppressed statin-induced apoptosis. The strategy to combine statins with bicarbonate can lead to reduction in the chance of the severe adverse events including myopathy or rhabdmyolysis. PMID:17553641

  19. The Interplays between Autophagy and Apoptosis Induced by Enterovirus 71

    PubMed Central

    Wang, Bei; Wang, Tao; Wang, Ji; Huang, He; Wang, Jianwei; Jin, Qi; Zhao, Zhendong

    2013-01-01

    Background Enterovirus 71 (EV71) is the causative agent of human diseases with distinct severity, from mild hand, foot and mouth disease to severe neurological syndromes, such as encephalitis and meningitis. The lack of understanding of viral pathogenesis as well as lack of efficient vaccine and drugs against this virus impedes the control of EV71 infection. EV71 virus induces autophagy and apoptosis; however, the relationship between EV71-induced autophagy and apoptosis as well as the influence of autophagy and apoptosis on virus virulence remains unclear. Methodology/Principal Findings In this study, it was observed that the Anhui strain of EV71 induced autophagy and apoptosis in human rhabdomyosarcoma (RD-A) cells. Additionally, by either applying chemical inhibitors or knocking down single essential autophagic or apoptotic genes, inhibition of EV71 induced autophagy inhibited the apoptosis both at the autophagosome formation stage and autophagy execution stage. However, inhibition of autophagy at the stage of autophagosome and lysosome fusion promoted apoptosis. In reverse, the inhibition of EV71-induced apoptosis contributed to the conversion of microtubule-associated protein 1 light chain 3-I (LC3-I) to LC3-II and degradation of sequestosome 1 (SQSTM1/P62). Furthermore, the inhibition of autophagy in the autophagsome formation stage or apoptosis decreased the release of EV71 viral particles. Conclusions/Significance In conclusion, the results of this study not only revealed novel aspect of the interplay between autophagy and apoptosis in EV71 infection, but also provided a new insight to control EV71 infection. PMID:23437282

  20. ATP depletion inhibits glucocorticoid-induced thymocyte apoptosis.

    PubMed Central

    Stefanelli, C; Bonavita, F; Stanic', I; Farruggia, G; Falcieri, E; Robuffo, I; Pignatti, C; Muscari, C; Rossoni, C; Guarnieri, C; Caldarera, C M

    1997-01-01

    In quiescent thymocytes, mitochondrial de-energization was not correlated to apoptotic death. In fact, thymocytes treated with oligomycin, a highly specific inhibitor of ATP synthase, alone or with atractyloside to block ATP translocation from the cytoplasm, were alive, even if their mitochondria were depolarized, as revealed by flow cytometry after Rhodamine 123 staining. Furthermore, oligomycin was a powerful inhibitor of apoptosis induced in rat thymocytes by dexamethasone and, to a lesser extent, by the calcium ionophore A23187 and etoposide, but was without effect when apoptosis was induced by staurosporine, and increased cell death in mitogen-treated thymocytes. The inhibition of apoptosis was confirmed by morphological criteria, inhibition of inter-nucleosomal DNA fragmentation and inhibition of the loss of membrane integrity. The anti-apoptotic effect of oligomycin in cells treated with A23187 or etoposide was correlated to the inhibition of protein synthesis, while inhibition of apoptosis induced by dexamethasone, already evident at an oligomycin concentration of 10 ng/ml, was instead strictly correlated to the effect exerted on the cellular ATP level. Thymocyte apoptosis triggered by dexamethasone was blocked or delayed by inhibitors of respiratory-chain uncouplers, inhibitors of ATP synthase and antioxidants: a lasting protection from dexamethasone-induced apoptosis was always correlated to a drastic and rapid reduction in ATP level (31-35% of control), while a delay in the death process was characterized by a moderate decrease in ATP (73-82% of control). Oligomycin inhibited the specific binding of radioactive corticosteroid to thymocyte nuclei, confirming the inhibitory effect of ATP depletion on glucocorticoid binding and suggesting that ATP depletion is a common mediator of the anti-apoptotic action of different effectors in glucocorticoid-induced apoptosis. In conclusion, the reported data indicate that ATP may act as a cellular modulator of some

  1. ATP depletion inhibits glucocorticoid-induced thymocyte apoptosis.

    PubMed

    Stefanelli, C; Bonavita, F; Stanic', I; Farruggia, G; Falcieri, E; Robuffo, I; Pignatti, C; Muscari, C; Rossoni, C; Guarnieri, C; Caldarera, C M

    1997-03-15

    In quiescent thymocytes, mitochondrial de-energization was not correlated to apoptotic death. In fact, thymocytes treated with oligomycin, a highly specific inhibitor of ATP synthase, alone or with atractyloside to block ATP translocation from the cytoplasm, were alive, even if their mitochondria were depolarized, as revealed by flow cytometry after Rhodamine 123 staining. Furthermore, oligomycin was a powerful inhibitor of apoptosis induced in rat thymocytes by dexamethasone and, to a lesser extent, by the calcium ionophore A23187 and etoposide, but was without effect when apoptosis was induced by staurosporine, and increased cell death in mitogen-treated thymocytes. The inhibition of apoptosis was confirmed by morphological criteria, inhibition of inter-nucleosomal DNA fragmentation and inhibition of the loss of membrane integrity. The anti-apoptotic effect of oligomycin in cells treated with A23187 or etoposide was correlated to the inhibition of protein synthesis, while inhibition of apoptosis induced by dexamethasone, already evident at an oligomycin concentration of 10 ng/ml, was instead strictly correlated to the effect exerted on the cellular ATP level. Thymocyte apoptosis triggered by dexamethasone was blocked or delayed by inhibitors of respiratory-chain uncouplers, inhibitors of ATP synthase and antioxidants: a lasting protection from dexamethasone-induced apoptosis was always correlated to a drastic and rapid reduction in ATP level (31-35% of control), while a delay in the death process was characterized by a moderate decrease in ATP (73-82% of control). Oligomycin inhibited the specific binding of radioactive corticosteroid to thymocyte nuclei, confirming the inhibitory effect of ATP depletion on glucocorticoid binding and suggesting that ATP depletion is a common mediator of the anti-apoptotic action of different effectors in glucocorticoid-induced apoptosis. In conclusion, the reported data indicate that ATP may act as a cellular modulator of some

  2. Apoptosis in vascular cells induced by cold atmospheric plasma treatment

    NASA Astrophysics Data System (ADS)

    Sladek, Raymond; Stoffels, Eva

    2006-10-01

    Apoptosis is a natural mechanism of cellular self-destruction. It can be triggered by moderate, yet irreversible damage. Apoptosis plays a major role in tissue renewal. Artificial apoptosis induction will become a novel therapy that meets all requirements for tissue-saving surgery. Diseased tissues can disappear without inflammation and scarring. This is particularly important in treatment of blockages in body tracts (e.g. cardiovascular diseases). Artificial induction of apoptosis can be achieved by means of cold plasma treatment. In this work an atmospheric micro-plasma operated in helium/air has been used to induce apoptosis in vascular cells. Parametric studies of apoptosis induction have been conducted; the efficiency is almost 100%. The apoptotic factors are ROS/RNS (reactive oxygen and nitrogen species). Their densities in the plasma have been measured by mass spectrometry. For apoptosis induction, RNS seem to be more important than ROS, because of their relative abundance. Moreover, addition of a ROS scavenger (ascorbic acid) to the cell culture medium does not reduce the occurrence of apoptosis. Cold plasma is a very efficient tool for fundamental studies of apoptosis, and later, for controlled tissue removal in vivo.

  3. Apoptosis signal-regulating kinase 1 mediates denbinobin-induced apoptosis in human lung adenocarcinoma cells

    PubMed Central

    Kuo, Chen-Tzu; Chen, Bing-Chang; Yu, Chung-Chi; Weng, Chih-Ming; Hsu, Ming-Jen; Chen, Chien-Chih; Chen, Mei-Chieh; Teng, Che-Ming; Pan, Shiow-Lin; Bien, Mauo-Ying; Shih, Chung-Hung; Lin, Chien-Huang

    2009-01-01

    In the present study, we explore the role of apoptosis signal-regulating kinase 1 (ASK1) in denbinobin-induced apoptosis in human lung adenocarcinoma (A549) cells. Denbinobin-induced cell apoptosis was attenuated by an ASK1 dominant-negative mutant (ASK1DN), two antioxidants (N-acetyl-L-cysteine (NAC) and glutathione (GSH)), a c-Jun N-terminal kinase (JNK) inhibitor (SP600125), and an activator protein-1 (AP-1) inhibitor (curcumin). Treatment of A549 cells with denbinobin caused increases in ASK1 activity and reactive oxygen species (ROS) production, and these effects were inhibited by NAC and GSH. Stimulation of A549 cells with denbinobin caused JNK activation; this effect was markedly inhibited by NAC, GSH, and ASK1DN. Denbinobin induced c-Jun phosphorylation, the formation of an AP-1-specific DNA-protein complex, and Bim expression. Bim knockdown using a bim short interfering RNA strategy also reduced denbinobin-induced A549 cell apoptosis. The denbinobin-mediated increases in c-Jun phosphorylation and Bim expression were inhibited by NAC, GSH, SP600125, ASK1DN, JNK1DN, and JNK2DN. These results suggest that denbinobin might activate ASK1 through ROS production to cause JNK/AP-1 activation, which in turn induces Bim expression, and ultimately results in A549 cell apoptosis. PMID:19405983

  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. Molecular mechanisms of nutlin-induced apoptosis in multiple myeloma: evidence for p53-transcription-dependent and -independent pathways.

    PubMed

    Saha, Manujendra N; Jiang, Hua; Chang, Hong

    2010-09-15

    Multiple myeloma (MM) is an incurable plasma cell malignancy in which p53 is rarely mutated. Thus, activation of the p53 pathway by a small molecule inhibitor of the p53-MDM2 interaction, nutlin, in MM cells retaining wild type p53 is an attractive therapeutic strategy. Recently we reported that nutlin plus velcade (a proteasome inhibitor) displayed a synergistic response in MM. However, the mechanism of the p53-mediated apoptosis in MM has not been fully understood. Our data show that nutlin-induced apoptosis correlated with reduction in cell viability, upregulation of p53, p21 and MDM2 protein levels with a simultaneous increase in pro-apoptotic targets PUMA, Bax and Bak and downregulation of anti-apoptotic targets Bcl2 and survivin and activation of caspase in MM cells harboring wild type p53. Nutlin-induced apoptosis was inhibited when activation of caspase was blocked by the caspase inhibitor. Nutlin caused mitochondrial translocation of p53 where it binds with Bcl2, leading to cytochrome C release. Moreover, blocking the transcriptional arm of p53 by the p53-specific transcriptional inhibitor, pifithrin-α, not only inhibited nutlin-induced upregulation of p53-transcriptional targets but also augmented apoptosis in MM cells, suggesting an association of transcription-independent pathway of apoptosis. However, inhibitor of mitochondrial translocation of p53, PFT-μ, did not prevent nutlin-induced apoptosis, suggesting that the p53 transcription-dependent pathway was also operational in nutlin-induced apoptosis in MM. Our study provides the evidence that nutlin-induced apoptosis in MM cells is mediated by transcription-dependent and -independent pathways and supports further clinical evaluation of nutlin as a novel therapeutic agent in MM. PMID:20595817

  6. Synergistic Induction of Apoptosis in Brain Cancer Cells by Targeted Co delivery of siRNA and Anti-cancer drugs

    PubMed Central

    Kim, Cheoljin; Shah, Birju P.; Subramaniam, Prasad; Lee, Ki-Bum

    2011-01-01

    Multiple dysregulated pathways in tumors necessitate targeting multiple oncogenic elements by combining orthogonal therapeutic moieties like short-interfering RNAs (siRNA) and drug molecules in order to achieve a synergistic therapeutic effect. In this manuscript, we describe the synthesis of cyclodextrin-modified dendritic polyamines (DexAMs) and their application as a multicomponent delivery vehicle for translocating siRNA and anticancer drugs. The presence of β-cyclodextrins in our DexAMs facilitated complexation and intracellular uptake of hydrophobic anticancer drugs-Suberoylanilide hydroxamic acid (SAHA) and Erlotinib, whereas the cationic polyamine backbone allowed for electrostatic interaction with the negatively charged siRNA. The DexAMs complexes were found to have minimal cytotoxicity over a wide range of concentrations and were found to efficiently deliver siRNA, thereby silencing the expression of targeted genes. As a proof-of concept, we demonstrated that upon appropriate modification with targeting ligands, we were able to simultaneously deliver multiple payloads -siRNA against oncogenic receptor, EGFRvIII and anti-cancer drugs (SAHA or erlotinib) efficiently and selectively to glioblastoma cells. Co-delivery of siRNA-EGFRvIII and SAHA/Erlotinib in glioblastoma cells was found to significantly inhibit cell proliferation and induce apoptosis, as compared to the individual treatments. PMID:21793576

  7. Recovering drug-induced apoptosis subnetwork from Connectivity Map data.

    PubMed

    Yu, Jiyang; Putcha, Preeti; Silva, Jose M

    2015-01-01

    The Connectivity Map (CMAP) project profiled human cancer cell lines exposed to a library of anticancer compounds with the goal of connecting cancer with underlying genes and potential treatments. Since the therapeutic goal of most anticancer drugs is to induce tumor-selective apoptosis, it is critical to understand the specific cell death pathways triggered by drugs. This can help to better understand the mechanism of how cancer cells respond to chemical stimulations and improve the treatment of human tumors. In this study, using CMAP microarray data from breast cancer cell line MCF7, we applied a Gaussian Bayesian network modeling approach and identified apoptosis as a major drug-induced cellular-pathway. We then focused on 13 apoptotic genes that showed significant differential expression across all drug-perturbed samples to reconstruct the apoptosis network. In our predicted subnetwork, 9 out of 15 high-confidence interactions were validated in the literature, and our inferred network captured two major cell death pathways by identifying BCL2L11 and PMAIP1 as key interacting players for the intrinsic apoptosis pathway and TAXBP1 and TNFAIP3 for the extrinsic apoptosis pathway. Our inferred apoptosis network also suggested the role of BCL2L11 and TNFAIP3 as "gateway" genes in the drug-induced intrinsic and extrinsic apoptosis pathways. PMID:25883971

  8. Alpha fetoprotein antagonizes apoptosis induced by paclitaxel in hepatoma cells in vitro.

    PubMed

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

    2016-01-01

    Hepatocellular carcinoma (HCC) cell resistance to the effects of paclitaxel has not been adequately addressed. In this study, we found that paclitaxel significantly inhibited the viability of HLE, Bel 7402 and L-02 cells in a dose- and time-dependent manner. HLE cells and L-02 cells resisted the cytotoxicity of paclitaxel when transfected with pcDNA3.1-afp vectors. However, Bel 7402 cell sensitivity to paclitaxel was increased when transfected with alpha fetoprotein (AFP)-siRNA. Bel 7402 cell resistance to paclitaxel was associated with the expression of the "stemness" markers CD44 and CD133. Paclitaxel significantly inhibited growth and promoted apoptosis in HLE cells and L-02 cells by inducing fragmentation of caspase-3 and inhibiting the expression of Ras and Survivin, but pcDNA3.1-afp vectors prevented these effects. However, paclitaxel could not significantly promote the cleavage of caspase-3 or suppress the expression of Ras and Survivin in Bel 7402 cells. Silenced expression of AFP may be synergistic with paclitaxel to restrain proliferation and induce apoptosis, enhance cleavage of caspase-3, and suppress the expression of Ras and Survivin. Taken together, AFP may be an important molecule acting against paclitaxel-inhibited proliferation and induced apoptosis in HCC cells via repressing the activity of caspase-3 and stimulating the expression of Ras and Survivin. Targeted inhibition of AFP expression after treatment with paclitaxel is an available strategy for the therapy of patients with HCC. PMID:27255186

  9. Alpha fetoprotein antagonizes apoptosis induced by paclitaxel in hepatoma cells in vitro

    PubMed Central

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

    2016-01-01

    Hepatocellular carcinoma (HCC) cell resistance to the effects of paclitaxel has not been adequately addressed. In this study, we found that paclitaxel significantly inhibited the viability of HLE, Bel 7402 and L-02 cells in a dose- and time-dependent manner. HLE cells and L-02 cells resisted the cytotoxicity of paclitaxel when transfected with pcDNA3.1-afp vectors. However, Bel 7402 cell sensitivity to paclitaxel was increased when transfected with alpha fetoprotein (AFP)-siRNA. Bel 7402 cell resistance to paclitaxel was associated with the expression of the “stemness” markers CD44 and CD133. Paclitaxel significantly inhibited growth and promoted apoptosis in HLE cells and L-02 cells by inducing fragmentation of caspase-3 and inhibiting the expression of Ras and Survivin, but pcDNA3.1-afp vectors prevented these effects. However, paclitaxel could not significantly promote the cleavage of caspase-3 or suppress the expression of Ras and Survivin in Bel 7402 cells. Silenced expression of AFP may be synergistic with paclitaxel to restrain proliferation and induce apoptosis, enhance cleavage of caspase-3, and suppress the expression of Ras and Survivin. Taken together, AFP may be an important molecule acting against paclitaxel-inhibited proliferation and induced apoptosis in HCC cells via repressing the activity of caspase-3 and stimulating the expression of Ras and Survivin. Targeted inhibition of AFP expression after treatment with paclitaxel is an available strategy for the therapy of patients with HCC. PMID:27255186

  10. Ketamine-induced apoptosis in cultured rat cortical neurons

    SciTech Connect

    Takadera, Tsuneo . E-mail: t-takadera@hokuriku-u.ac.jp; Ishida, Akira; Ohyashiki, Takao

    2006-01-15

    Recent data suggest that anesthetic drugs cause neurodegeneration during development. Ketamine is frequently used in infants and toddlers for elective surgeries. The purpose of this study is to determine whether glycogen synthase kinase-3 (GSK-3) is involved in ketamine-induced apoptosis. Ketamine increased apoptotic cell death with morphological changes which were characterized by cell shrinkage, nuclear condensation or fragmentation. In addition, insulin growth factor-1 completely blocked the ketamine-induced apoptotic cell death. Ketamine decreased Akt phosphorylation. GSK-3 is known as a downstream target of Akt. The selective inhibitors of GSK-3 prevented the ketamine-induced apoptosis. Moreover, caspase-3 activation was accompanied by the ketamine-induced cell death and inhibited by the GSK-3 inhibitors. These results suggest that activation of GSK-3 is involved in ketamine-induced apoptosis in rat cortical neurons.

  11. Reduction of apoptosis by proanthocyanidin-induced autophagy in the human gastric cancer cell line MGC-803

    PubMed Central

    NIE, CHAO; ZHOU, JIE; QIN, XIAOKANG; SHI, XIANMING; ZENG, QINGQI; LIU, JIA; YAN, SHIHAI; ZHANG, LEI

    2016-01-01

    Proanthocyanidins are flavonoids that are widely present in the skin and seeds of various plants, with the highest content in grape seeds. Many experiments have shown that proanthocyanidins have antitumor activity both in vivo and in vitro. Autophagy and apoptosis of tumor cells induced by drugs are two of the major causes of tumor cell death. However, reports on the effect of autophagy induced by drugs in tumor cells are not consistent and suggest that autophagy can have synergistic or antagonistic effects with apoptosis. This research was aimed at investigating whether proanthocyanidins induced autophagy and apoptosis in human gastric cancer cell line MGC-803 cells and to identify the mechanism of proanthocyanidins action to further determine the effect of proanthocyanidins-induced autophagy on apoptosis. MTT assay was used to examine the proanthocyanidin cytotoxicity against human gastric cancer cell line MGC-803. Transmission electron microscopy and monodansylcadaverine (MDC) staining were used to detect autophagy. Annexin V APC/7-AAD double staining and Hoechst 33342/propidium iodide (PI) double staining were used to explore apoptosis. Western blotting was used to determine expression of proteins related to autophagy and apoptosis. Real-time quantitative PCR technology was used to determine the mRNA level of Beclin1 and BCL-2. The results showed that proanthocyanidins exhibit a significant inhibitory effect on the human gastric cancer cell line MGC-803 proliferation in vitro and simultaneously activate autophagy and apoptosis to promote cell death. Furthermore, when proanthocyanidin-induced autophagy is inhibited, apoptosis increases significantly, proanthocyanidins can be used together with autophagy inhibitors to enhance cytotoxicity. PMID:26572257

  12. Apoptosis induced by dioscin in Hela cells.

    PubMed

    Cai, Jing; Liu, Mingjie; Wang, Zhao; Ju, Yong

    2002-02-01

    Dioscin, a saponin extracted from the root of Polygonatum Zanlanscianense Pamp, markedly inhibited proliferation of Hela cells. The results indicated that Hela cells underwent apoptosis in dose- and time-dependent manners when treated with Dioscin. Caspase-3, -8 and -9 activities were also detected. The low enzymatic activity of caspase-8 and high activity of caspase-9 showed that the mitochondrial pathway was activated in apoptosis. The reduced expression of the survival protein Bcl-2 also confirmed this result. These studies may be significant in finding a new drug to treat human cervical cancer. PMID:11853164

  13. Mountain grown ginseng induces apoptosis in HL-60 cells and its mechanism have little relation with TNF-alpha production.

    PubMed

    Koo, Hyun-Na; Jeong, Hyun-Ja; Choi, In-Young; An, Hyo-Jin; Moon, Phil-Dong; Kim, Seong-Jin; Jee, Seon-Young; Um, Jae-Young; Hong, Seung-Heon; Shin, Soon-Shik; Yang, Deok-Chun; Seo, Yong-Suk; Kim, Hyung-Min

    2007-01-01

    The root of ginseng is one of the most popular natural tonics in Oriental countries. Ginseng grown in the wild, deep in the mountains, is known as Sansam (mountain grown ginseng, MGG). MGG belongs to Araliaceae and Panax. In this study, we investigated the effects of MGG on the cytotoxicity, induction of apoptosis and the putative pathways of its actions in human promyelocytic leukemia cells, HL-60. Using apoptosis analysis, we found that MGG is a potent inducer of apoptosis, but it has less effect on human peripheral blood mononuclear cells. Caspase-3 activation and subsequent apoptotic cell death in MGG-treated cells were partially blocked by the caspase-3 inhibitor, Z-DEVD-FMK. MGG also inhibited the caspase-8 activity. To determine whether MGG-induced apoptosis is involved in tumor necrosis factor-alpha (TNF-alpha) secretion, TNF-alpha secretion was quantified by enzyme-linked immunosorbent assay (ELISA) method. Unexpectedly, MGG significantly decreased the TNF-alpha secretion compared to the control. These results suggest that MGG-induced cytotoxicity have little relation with the secretion of TNF-alpha in HL-60 cells. Furthermore, MGG with rIFN-gamma synergistically increased nitric oxide (NO) production in mouse peritoneal macrophages. Taken together, our data indicate that MGG is a potent inducer of apoptosis on HL-60 cells and these abilities could be used clinically for the treatment of cancer. PMID:17265560

  14. miR-30e Blocks Autophagy and Acts Synergistically with Proanthocyanidin for Inhibition of AVEN and BIRC6 to Increase Apoptosis in Glioblastoma Stem Cells and Glioblastoma SNB19 Cells

    PubMed Central

    Chakrabarti, Mrinmay; Klionsky, Daniel J.; Ray, Swapan K.

    2016-01-01

    Glioblastoma is the most common and malignant brain tumor in humans. It is a heterogeneous tumor harboring glioblastoma stem cells (GSC) and other glioblastoma cells that survive and sustain tumor growth in a hypoxic environment via induction of autophagy and resistance to apoptosis. So, a therapeutic strategy to inhibit autophagy and promote apoptosis could greatly help control growth of glioblastoma. We created hypoxia using sodium sulfite (SS) for induction of substantiated autophagy in human GSC and glioblastoma SNB19 cells. Induction of autophagy was confirmed by acridine orange (AO) staining and significant increase in Beclin-1 in autophagic cells. microRNA database (miRDB) search suggested that miR-30e could suppress the autophagy marker Beclin-1 and also inhibit the caspase activation inhibitors (AVEN and BIRC6). Pro-apoptotic effect of proanthocyanidin (PAC) has not yet been explored in glioblastoma cells. Combination of 50 nM miR-30e and 150 μM PAC acted synergistically for inhibition of viability in both cells. This combination therapy most effectively altered expression of molecules for inhibition of autophagy and induced extrinsic and intrinsic pathways of apoptosis through suppression of AVEN and BIRC6. Collectively, combination of miR-30e and PAC is a promising therapeutic strategy to inhibit autophagy and increase apoptosis in GSC and SNB19 cells. PMID:27388765

  15. Role of Sialidase in Mycoplasma alligatoris-induced Pulmonary Fibroblast Apoptosis

    PubMed Central

    Hunt, Marguerite E.; Brown, Daniel R.

    2007-01-01

    Mycoplasma alligatoris causes acute lethal cardiopulmonary disease of susceptible hosts. A survey of its genome implicated sialidase and hyaluronidase, synergistic regulators of hyaluronan receptor CD44-mediated signal transduction leading to apoptotic cell death, as virulence factors of M. alligatoris. In this study, after the existence of a CD44 homolog in alligators was established by immunolabeling primary pulmonary fibroblasts with monoclonal antibody IM7 against murine CD44, the sialidase inhibitor 2,3-didehydro-2-deoxy-N-acetylneuraminic acid (DANA) was used to examine the effects of sialidase on fibroblast apoptosis following in vitro infection with M. alligatoris. While their CD44 expression remained constant, infected cells exhibited morphologic changes characteristic of apoptosis including decreased size, rounding, disordered a-tubulin, and nuclear disintegration compared to untreated controls. DANA was a potent, non-toxic inhibitor of the sialidase activity, equivalent to about 1 mU of Clostridium perfringens Type VI sialidase, expressed by M. alligatoris in the inoculum. Although DANA did not measurably reduce the proportion of infected fibroblasts labeled by a specific ligand of activated caspases, co-incubation with DANA protected (P < 0.01) fibroblasts in a concentration-dependent fashion from the M. alligatoris-induced trends toward increased apoptosis receptor CD95 expression, and increased 5-bromo-2′-deoxyuridine incorporation measured in a terminal dUTP nick end-labeling apoptosis assay. In contrast, incubation with 200-fold excess purified C. perfringens sialidase alone did not affect CD95 expression or chromatin integrity, or induce fibroblast apoptosis. From those observations we conclude that interaction of its sialidase with hyaluronidase or another virulence factor(s) is necessary to elicit the pro-apoptotic effects of M. alligatoris infection. PMID:17276629

  16. Antioxidants induce apoptosis of rat ovarian theca-interstitial cells.

    PubMed

    Rzepczynska, Izabela J; Foyouzi, Nastaran; Piotrowski, Piotr C; Celik-Ozenci, Ciler; Cress, Amanda; Duleba, Antoni J

    2011-01-01

    Regulation of growth of ovarian theca-interstitial tissues is essential for normal ovarian development and function. Reactive oxygen species are involved in modulation of signal transduction pathways, including regulation of tissue growth and apoptosis. Previously, we have demonstrated that antioxidants inhibit proliferation of theca-interstitial cells. This report evaluates the effects of antioxidants on apoptosis of rat theca-interstitial cells. The cells were cultured in chemically defined media without or with vitamin E succinate and ebselen. Apoptosis was evaluated by cytochemical assessment of nuclear morphology, activity of executioner caspases 3 and 7, and determination of staining with annexin V in combination with propidium iodide. Both tested antioxidants induced significant morphological changes consistent with apoptosis, including chromatin condensation, nuclear shrinkage, and pyknosis. Antioxidants also induced other hallmarks of apoptosis including increased activity of caspases 3/7 as well as increased staining with annexin V. The present findings demonstrate that antioxidants with distinctly different mechanisms of action induce a series of events consistent with the process of apoptosis in ovarian mesenchyme. These observations may be of translational-clinical relevance, providing mechanistic support for the use of antioxidants in the treatment of PCOS, a condition associated with excessive growth and activity of theca-interstitial cells. PMID:20844276

  17. X-ray-induced cell death: Apoptosis and necrosis

    SciTech Connect

    Nakano, Hisako; Shinohara, Kunio

    1994-10-01

    X-ray-induced cell death in MOLT-4N1, a subclone of MOLT-4 cells, and M10 cells was studied with respect to their modes of cell death, apoptosis and necrosis. MOLT-4N1 cells showed radiosensitivity similar to that of M10 cells, a radiosensitive mutant of L5178Y, as determined by the colony formation assay. Analysis of cell size demonstrated that MOLT-4N1 cells increased in size at an early stage after irradiation and then decreased to a size smaller than that of control cells, whereas the size of irradiated M10 cells increased continuously. Apoptosis detected by morphological changes and DNA ladder formation (the cleavage of DNA into oligonucleosomal fragments) occurred in X-irradiated MOLT-4N1 cells but not in M10 cells. Pulsed-field gel electrophoresis showed that the ladder formation involved an intermediate-sized DNA (about 20 kbp). Most of the DNA was detected at the origin in both methods of electrophoresis in the case of M10 cells, though a trace amount of ladder formation was observed. Heat treatment of M10 cells induced apoptosis within 30 min after treatment, in contrast to MOLT-4N1 cells. The results suggest that apoptosis and necrosis are induced by X rays in a manner which is dependent on the cell line irrespective of the capability of the cells to develop apoptosis. DNA fragmentation was the earliest change observed in the development of apoptosis. 27 refs., 8 figs., 1 tab.

  18. Pomegranate extract induces apoptosis in human prostate cancer cells by modulation of the IGF-IGFBP axis

    PubMed Central

    Koyama, Satomi; Cobb, Laura J; Mehta, Hemal H; Seeram, Navindra P.; Heber, David; Pantuck, Allan J.; Cohen, Pinchas

    2009-01-01

    The IGF axis is critical for the regulation of apoptosis in many human cancer cell lines. Recently, potent anti-tumorigenic effects of pomegranate juice and extracts have been reported. Consequently, pomegranate has potential not only as a treatment but also as a preventative measure against certain types of cancer, including prostate. In this study, we investigated the relationship between pomegranate-induced apoptosis in human prostate cancer cells and the IGF/IGFBP system. Treatment of LAPC4 prostate cancer cells with 10 μg/ml POMx, a highly potent pomegranate extract prepared from skin and arils minus seeds and standardized to ellagitannin content (37% punicalagins by HPLC), resulted in inhibition of cell proliferation and induction of apoptosis. Interestingly, co-treatment with POMx and IGFBP-3 revealed synergistic stimulation of apoptosis and additive inhibition of cell growth. Western blot analysis revealed that treatment with POMx or POMx/IGFBP-3 combination resulted in increased JNK phosphorylation, and decreased Akt and mTOR activation, consistent with a growth inhibitory, pro-apoptotic function. We also investigated the relationship between IGF-1 and pomegranate-induced apoptosis in 22RV1 prostate cancer cells. Co-treatment with 100 ng/ml IGF-1 completely blocked apoptosis induction by POMx. In contrast, IGF-I failed to inhibit POMx-induced apoptosis in R- cells, suggesting the importance of IGF-IR. POMx-treatment decreased Igf1 mRNA expression in a dose-dependent manner indicating that its actions also involve tumor-specific suppression of IGF-1. These studies revealed novel interactions between the IGF system and pomegranate-induced apoptosis. PMID:19853487

  19. miR-30c and miR-181a synergistically modulate p53-p21 pathway in diabetes induced cardiac hypertrophy.

    PubMed

    Raut, Satish K; Singh, Gurinder B; Rastogi, Bhawna; Saikia, Uma Nahar; Mittal, Anupam; Dogra, Nilambra; Singh, Sandeep; Prasad, Rishikesh; Khullar, Madhu

    2016-06-01

    p53-p21 pathway mediates cardiomyocyte hypertrophy and apoptosis and is upregulated in diabetic cardiomyopathy (DbCM). We investigated role of microRNAs in regulating p53-p21 pathway in high glucose (HG)-induced cardiomyocyte hypertrophy and apoptosis. miR-30c and miR-181a were identified to target p53. Cardiac expression of microRNAs was measured in diabetic patients, diabetic rats, and in HG-treated cardiomyocytes. Effect of microRNAs over-expression and inhibition on HG-induced cardiomyocyte hypertrophy and apoptosis was examined. Myocardial expression of p53 and p21 genes was increased and expression of miR-30c and miR-181a was significantly decreased in diabetic patients, DbCM rats, and in HG-treated cardiomyocytes. Luciferase assay confirmed p53 as target of miR-30c and miR-181a. Over-expression of miR-30c or miR-181a decreased expression of p53, p21, ANP, cardiomyocyte cell size, and apoptosis in HG-treated cardiomyocytes. Concurrent over-expression of these microRNAs resulted in greater decrease in cardiomyocyte hypertrophy and apoptosis, suggesting a synergistic effect of these microRNAs. Our results suggest that dysregulation of miR-30c and miR-181a may be involved in upregulation of p53-p21 pathway in DbCM. PMID:27221738

  20. Cilostazol suppresses angiotensin II-induced apoptosis in endothelial cells

    PubMed Central

    SHI, MIAO-QIAN; SU, FEI-FEI; XU, XUAN; LIU, XIONG-TAO; WANG, HONG-TAO; ZHANG, WEI; LI, XUE; LIAN, CHENG; ZHENG, QIANG-SUN; FENG, ZHI-CHUN

    2016-01-01

    Patients with essential hypertension undergo endothelial dysfunction, particularly in the conduit arteries. Cilostazol, a type III phosphodiesterase inhibitor, serves a role in the inhibition of platelet aggregation and it is widely used in the treatment of peripheral vascular diseases. Previous studies have suggested that cilostazol suppresses endothelial dysfunction; however, it remains unknown whether cilostazol protects the endothelial function in essential hypertension. The aim of the present study was to investigate whether, and how, cilostazol suppresses angiotensin II (angII)-induced endothelial dysfunction. Human umbilical vein endothelial cells (HUVECs) and Sprague Dawley rats were exposed to angII and treated with cilostazol. Endothelial cell apoptosis and function, nitric oxide and superoxide production, phosphorylation (p) of Akt, and caspase-3 protein expression levels were investigated. AngII exposure resulted in the apoptosis of endothelial cells in vitro and in vivo. In vitro, cilostazol significantly suppressed the angII-induced apoptosis of HUVECs; however, this effect was reduced in the presence of LY294002, a phosphoinositide 3 kinase (PI3K) inhibitor. Furthermore, cilostazol suppressed the angII-induced p-Akt downregulation and cleaved caspase-3 upregulation. These effects were also alleviated by LY294002. In vivo, cilostazol suppressed the angII-induced endothelial cell apoptosis and dysfunction. Cilostazol was also demonstrated to partially reduced the angII-induced increase in superoxide production. The results of the present study suggested that cilostazol suppresses endothelial apoptosis and dysfunction by modulating the PI3K/Akt pathway. PMID:26862035

  1. Csk regulates angiotensin II-induced podocyte apoptosis.

    PubMed

    Zhang, Lu; Ren, Zhilong; Yang, Qian; Ding, Guohua

    2016-07-01

    Increasing data have shown that angiotensin II (Ang II) perpetuates podocyte injury and promotes progression to end-stage kidney disease. The mechanism underlying Ang II-induced podocyte apoptosis has not been established. C-terminal Src kinase (Csk) is a cytoplasmic kinase that interacts with scaffolding proteins involved in cell growth, adhesion, and polarization, and the role of Csk in regulating cellular apoptosis has gradually attracted attention. This study evaluates the role of Csk in Ang II-induced podocyte apoptosis. In vivo, Wistar rats were randomly subjected to a normal saline or Ang II infusion. In vitro, we exposed differentiated mouse podocytes to Ang II. Ang II increased Csk expression and induced podocyte apoptosis, stimulated Csk translocation and binding to Caveolin-1, and stimulated decreased Fyn pY416, increased Fyn pY529, and nephrin dephosphorylation. Csk knockdown prevented Ang II-induced podocyte apoptosis, reduced Fyn kinase inactivation, and increased the interaction between nephrin and the activated form of Fyn, accompanied by a reduced interaction between Csk and Caveolin-1. These findings indicate that Ang II induces podocyte injury via a Csk-dependent pathway. PMID:27225249

  2. Neem oil limonoids induces p53-independent apoptosis and autophagy.

    PubMed

    Srivastava, Pragya; Yadav, Neelu; Lella, Ravi; Schneider, Andrea; Jones, Anthony; Marlowe, Timothy; Lovett, Gabrielle; O'Loughlin, Kieran; Minderman, Hans; Gogada, Raghu; Chandra, Dhyan

    2012-11-01

    Azadirachta indica, commonly known as neem, has a wide range of medicinal properties. Neem extracts and its purified products have been examined for induction of apoptosis in multiple cancer cell types; however, its underlying mechanisms remain undefined. We show that neem oil (i.e., neem), which contains majority of neem limonoids including azadirachtin, induced apoptotic and autophagic cell death. Gene silencing demonstrated that caspase cascade was initiated by the activation of caspase-9, whereas caspase-8 was also activated late during neem-induced apoptosis. Pretreatment of cancer cells with pan caspase inhibitor, z-VAD inhibited activities of both initiator caspases (e.g., caspase-8 and -9) and executioner caspase-3. Neem induced the release of cytochrome c and apoptosis-inducing factor (AIF) from mitochondria, suggesting the involvement of both caspase-dependent and AIF-mediated apoptosis. p21 deficiency caused an increase in caspase activities at lower doses of neem, whereas p53 deficiency did not modulate neem-induced caspase activation. Additionally, neem treatment resulted in the accumulation of LC3-II in cancer cells, suggesting the involvement of autophagy in neem-induced cancer cell death. Low doses of autophagy inhibitors (i.e., 3-methyladenine and LY294002) did not prevent accumulation of neem-induced LC3-II in cancer cells. Silencing of ATG5 or Beclin-1 further enhanced neem-induced cell death. Phosphoinositide 3-kinase (PI3K) or autophagy inhibitors increased neem-induced caspase-3 activation and inhibition of caspases enhanced neem-induced autophagy. Together, for the first time, we demonstrate that neem induces caspase-dependent and AIF-mediated apoptosis, and autophagy in cancer cells. PMID:22915764

  3. Denbinobin induces apoptosis by apoptosis-inducing factor releasing and DNA damage in human colorectal cancer HCT-116 cells.

    PubMed

    Chen, Tzu-Hsuan; Pan, Shiow-Lin; Guh, Jih-Hwa; Chen, Chien-Chih; Huang, Yao-Ting; Pai, Hui-Chen; Teng, Che-Ming

    2008-11-01

    Denbinobin is a phenanthraquinone derivative present in the stems of Ephemerantha lonchophylla. We showed that denbinobin induces apoptosis in human colorectal cancer cells (HCT-116) in a concentration-dependent manner. The addition of a pan-caspase inhibitor (zVAD-fmk) did not suppress the denbinobin-induced apoptotic effect, and denbinobin-induced apoptosis was not accompanied by processing of procaspase-3, -6, -7, -9, and -8. However, denbinobin triggered the translocation of the apoptosis-inducing factor (AIF) from the mitochondria into the nucleus. Small interfering RNA targeting of AIF effectively protected HCT-116 cells against denbinobin-induced apoptosis. Denbinobin treatment also caused DNA damage, activation of the p53 tumor suppressor gene, and upregulation of numerous downstream effectors (p21WAF1/CIP1, Bax, PUMA, and NOXA). A HCT-116 xenograft model demonstrated the in vivo efficacy and low toxicity of denbinobin. Taken together, our findings suggest that denbinobin induces apoptosis of human colorectal cancer HCT-116 cells via DNA damage and an AIF-mediated pathway. These results indicate that denbinobin has potential as a novel anticancer agent. PMID:18607570

  4. Resveratrol synergistically augments anti-tumor effect of 5-FU in vitro and in vivo by increasing S-phase arrest and tumor apoptosis.

    PubMed

    Dun, Jiening; Chen, Xueyan; Gao, Haixia; Zhang, Yan; Zhang, Huajun; Zhang, Yongjian

    2015-12-01

    Many studies have shown that natural dietary agents, in combination with chemical agents, can improve the therapeutic response of cancers to chemotherapy and reduce the associated side-effects. In the present study, we investigated the therapeutic potential and mechanisms of anticancer effects for the combination of 5-fluorouracil (5-FU) and resveratrol (Res). In these studies, we employed the cancer cell lines TE-1 and A431 and an animal model of skin cancer. The presented results provide the first evidence that Res can enhance the anti-tumor potency of 5-FU by inducing S-phase arrest. The combination of Res and 5-FU demonstrates synergistic efficacy, causing tumor regression in a two-stage model of mouse skin carcinogenesis induced by DMBA and TPA. There was clear evidence of Res augmenting the growth inhibitory effect of 5-FU on the TE-1 and A431 cancer cells in vitro. In the in vivo studies, the tumor regression rate in the combination group increased significantly after four weeks of treatment (P < 0.01). The combination of 5-FU and Res significantly increased the percentage of apoptotic cells and the level of activated caspase-3, cleaved PARP and p53 proteins as well as increased the Bax/Bcl-2 ratio. In conclusion, the 5-FU/Res combination enabled a more effective inhibition of cell growth and the induction of apoptosis in cancer cells than 5-FU alone. The results of this study suggest that chemotherapy using natural dietary agents with chemical agents represents a superior cancer treatment option. PMID:25736303

  5. Calpain Inhibitor PD150606 Attenuates Glutamate Induced Spiral Ganglion Neuron Apoptosis through Apoptosis Inducing Factor Pathway In Vitro

    PubMed Central

    Song, Yong-Li; Chen, Xiao-Dong; Mi, Wen-Juan; Wang, Jian; Lin, Ying; Chen, Fu-Quan; Qiu, Jian-Hua

    2015-01-01

    Objective This research aimed to investigate whether glutamate induced spiral ganglion neurons (SGNs) apoptosis through apoptosis inducing factor (AIF) pathway. And verify whether PD150606, a calpain inhibitor could prevent apoptosis by inhibiting cleaving and releasing AIF in mitochondrion. Methods SGNs of postnatal days 0-3 were harvested and cultured in dishes. 20 mM Glu, the caspase inhibitor Z-VAD-FMK and calpain inhibitor PD150606 were added into cultured dishes separately. We used optical microscope and immunofluoresence staining to observe cell morphology and AIF distribution, RT-PCR and Westernblot to analyse AIF and calpain expression in SGNs. TUNEL assay was used to test cell apoptosis. Results Cell morphology and nuclear translocation of AIF were altered in SGNs by 20 mM Glu treated in vitro. The axon of SGN shortened, more apoptosis SGN were observed and the expression of AIF and calpain were up-regulated in Glu-treated group than the normal one (P<0.05). The same experiments were conducted in 20 mM+PD150606 treated group and 20 mM+Z-VAD-FMK group. Obviously AIF were located from cytoplasm to the nuclear and the expressions of AIF and calpain were down-regulated by PD150606 (P<0.05). Positive cells in TUNEL staining decreased after PD150606 treating. However, Z-VAD-FMK had no influence on AIF, calpain expression or cell apoptosis. Conclusion The AIF-related apoptosis pathway is involved in the process of Glu-induced SGN injury. Furthermore, the inhibition of calpain can prevent AIF from releasing the nuclear or inducing SGN apoptosis. PMID:25874633

  6. Hydroxycamptothecin induces apoptosis and inhibits tumor growth in colon cancer by the downregulation of survivin and XIAP expression

    PubMed Central

    2013-01-01

    Background 10-Hydroxycamptothecin (10-HCPT), isolated from a Chinese tree Camptotheca acuminate, inhibits the activity of topoisomerase I and has a broad spectrum of anticancer activity in vitro and in vivo. It has been shown that HCPT is more active and less toxic than conventional camptothecins and can induce cancer cell apoptosis. However, the mechanisms of HCPT-induced apoptosis in colon cancer cells remain unclear. In this study, we investigated the effects of HCPT on apoptosis of colon cancer and underlying mechanism. Methods Cell proliferation was measured by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide) assay, and apoptosis was measured using terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) assay. Expression of genes was detected using real-time reverse transcription-polymerase chain reaction (real time-PCR) and Western blot. Tumor growth in vivo was evaluated using a nude mouse xenograft model. Results HCPT could significantly inhibit cell proliferation and induce apoptosis in colon cancer SW1116 and Colo 205 cells in dose- and time-dependent manners. HCPT treatment activated the activities of caspase 3, 7, 8 and 9, downregulated the expression of survivin, survivinΔEx3, survivin-3B and XIAP, and upregulated expression of surviving 2B. Moreover, the combination of HCPT and 5-fluorouracial (5-FU) synergistically induced apoptosis and downregulated the expression of survivin and XIAP. Knockdown of survivin and XIAP by siRNA sensitized colon cancer to HCTP-induced apoptosis. Furthermore, HCPT treatment significantly inhibited SW1116 xenograft tumor growth. Conclusions Our results elucidate new mechanisms of HCPT antitumor by the downregulation of survivin and XIAP expression. The combination of HCPT with 5-FU or IAP inhibitors may be a potential strategy for colon cancer treatment. PMID:23721525

  7. Rabies virus infects mouse and human lymphocytes and induces apoptosis.

    PubMed Central

    Thoulouze, M I; Lafage, M; Montano-Hirose, J A; Lafon, M

    1997-01-01

    Attenuated and highly neurovirulent rabies virus strains have distinct cellular tropisms. Highly neurovirulent strains such as the challenge virus standard (CVS) are highly neurotropic, whereas the attenuated strain ERA also infects nonneuronal cells. We report that both rabies virus strains infect activated murine lymphocytes and the human lymphoblastoid Jurkat T-cell line in vitro. The lymphocytes are more permissive to the attenuated ERA rabies virus strain than to the CVS strain in both cases. We also report that in contrast to that of the CVS strain, ERA viral replication induces apoptosis of infected Jurkat T cells, and cell death is concomitant with viral glycoprotein expression, suggesting that this protein has a role in the induction of apoptosis. Our data indicate that (i) rabies virus infects lymphocytes, (ii) lymphocyte infection with the attenuated rabies virus strain causes apoptosis, and (iii) apoptosis does not hinder rabies virus production. In contrast to CVS, ERA rabies virus and other attenuated rabies virus vaccines stimulate a strong immune response and are efficient live vaccines. The paradoxical finding that a rabies virus triggers a strong immune response despite the fact that it infects lymphocytes and induces apoptosis is discussed in terms of the function of apoptosis in the immune response. PMID:9311815

  8. The retinoblastoma protein induces apoptosis directly at the mitochondria

    PubMed Central

    Hilgendorf, Keren I.; Leshchiner, Elizaveta S.; Nedelcu, Simona; Maynard, Mindy A.; Calo, Eliezer; Ianari, Alessandra; Walensky, Loren D.; Lees, Jacqueline A.

    2013-01-01

    The retinoblastoma protein gene RB-1 is mutated in one-third of human tumors. Its protein product, pRB (retinoblastoma protein), functions as a transcriptional coregulator in many fundamental cellular processes. Here, we report a nonnuclear role for pRB in apoptosis induction via pRB's direct participation in mitochondrial apoptosis. We uncovered this activity by finding that pRB potentiated TNFα-induced apoptosis even when translation was blocked. This proapoptotic function was highly BAX-dependent, suggesting a role in mitochondrial apoptosis, and accordingly, a fraction of endogenous pRB constitutively associated with mitochondria. Remarkably, we found that recombinant pRB was sufficient to trigger the BAX-dependent permeabilization of mitochondria or liposomes in vitro. Moreover, pRB interacted with BAX in vivo and could directly bind and conformationally activate BAX in vitro. Finally, by targeting pRB specifically to mitochondria, we generated a mutant that lacked pRB's classic nuclear roles. This mito-tagged pRB retained the ability to promote apoptosis in response to TNFα and also additional apoptotic stimuli. Most importantly, induced expression of mito-tagged pRB in Rb−/−;p53−/− tumors was sufficient to block further tumor development. Together, these data establish a nontranscriptional role for pRB in direct activation of BAX and mitochondrial apoptosis in response to diverse stimuli, which is profoundly tumor-suppressive. PMID:23618872

  9. 6-Gingerol induces autophagy to protect HUVECs survival from apoptosis.

    PubMed

    Wang, Shaopeng; Sun, Xiance; Jiang, Liping; Liu, Xiaofang; Chen, Min; Yao, Xiaofeng; Sun, Qinghua; Yang, Guang

    2016-08-25

    6-Gingerol, the major pharmacologically-active component of ginger, has the potential to prevent heart disease. However, the mechanisms are not well understood. In this study, the protective effect of 6-gingerol against hydrogen peroxide-induced apoptosis in human umbilical vein endothelial cells (HUVECs) was investigated. Apoptosis was detected by Hoechst 33342 and Flow cytometry analysis. To further elucidate the crosstalk between apoptosis and autophagy, we tested the expression of autophagy related proteins, LC3B, Bcl-2, Beclin1, AKT, p-AKT, mechanistic target of rapamycin (mTOR), and p-mTOR. Furthermore, mitochondrial membrane potential and the intracellular generation of reactive oxygen species (ROS) were also investigated. Our data revealed that 6-gingerol significantly reduced apoptosis by inducing autophagy. It has been demonstrated that 6-gingerol suppressed the phosphatidylinositol 3-kinase (PI3K)/AKT/mTOR signaling pathway, increased the expression of Beclin1 to promote autophagy, and increased Bcl-2 expression to inhibit apoptosis. In addition, the damage of mitochondrial was protected, and ROS level was decreased by 6-gingerol. These firmly indicate 6-gingerol has a strong protective ability against the apoptosis caused by oxidative stress in HUVECs, and the mechanism may relate to the induction of autophagy. Our data suggest 6-gingerol may be beneficial in the prevention of atherosclerosis. PMID:27451028

  10. Autophagy Regulates Colistin-Induced Apoptosis in PC-12 Cells

    PubMed Central

    Zhang, Ling; Zhao, Yonghao; Ding, Wenjian; Jiang, Guozheng; Lu, Ziyin; Li, Li; Wang, Jinli

    2015-01-01

    Colistin is a cyclic cationic polypeptide antibiotic with activity against multidrug-resistant Gram-negative bacteria. Our recent study demonstrated that colistin induces apoptosis in primary chick cortex neurons and PC-12 cells. Although apoptosis and autophagy have different impacts on cell fate, there is a complex interaction between them. Autophagy plays an important role as a homeostasis regulator by removing excessive or unnecessary proteins and damaged organelles. The aim of the present study was to investigate the modulation of autophagy and apoptosis regulation in PC-12 cells in response to colistin treatment. PC-12 cells were exposed to colistin (125 to 250 μg/ml), and autophagy was detected by visualization of monodansylcadaverine (MDC)-labeled vacuoles, LC3 (microtubule-associated protein 1 light chain 3) immunofluorescence microscopic examination, and Western blotting. Apoptosis was measured by flow cytometry, Hoechst 33258 staining, and Western blotting. Autophagosomes were observed after treatment with colistin for 12 h, and the levels of LC3-II gene expression were determined; observation and protein levels both indicated that colistin induced a high level of autophagy. Colistin treatment also led to apoptosis in PC-12 cells, and the level of caspase-3 expression increased over the 24-h period. Pretreatment of cells with 3-methyladenine (3-MA) increased colistin toxicity in PC-12 cells remarkably. However, rapamycin treatment significantly increased the expression levels of LC3-II and beclin 1 and decreased the rate of apoptosis of PC-12 cells. Our results demonstrate that colistin induced autophagy and apoptosis in PC-12 cells and that the latter was affected by the regulation of autophagy. It is very likely that autophagy plays a protective role in the reduction of colistin-induced cytotoxicity in neurons. PMID:25645826

  11. Hydrogen peroxide induces apoptosis via a mitochondrial pathway in chondrocytes

    NASA Astrophysics Data System (ADS)

    Zhuang, Cai-ping; Liang, Qian; Wang, Xiao-ping; Chen, Tong-sheng

    2012-03-01

    The degenerative joint disease such as osteoarthritis (OA) is closely associated with the death of chondrocytes in apoptosis fashion. Hydrogen peroxide (H2O2), higher expression following acute damage in OA patients, has been shown to be up-regulated during apoptosis in a bulk of experimental models. This study was aimed to explore the mechanism of H2O2-induced rabbit chondrocytes apoptosis. Articular cartilage was biopsied from the joints of 6 weeks old New Zealand rabbits. Cell Counting Kit (CCK-8) assay was used to assess the inhibitory effect of H2O2 on cell viability. H2O2 treatment induced a remarkable reduction of cell viability. We used flow cytometry to assess the form of cell death with Annexin-V/PI double staining, and found that H2O2 treatment induced apoptosis in a dose-and time-dependent manner. Exposure of chondrocytes to 1.5 mM of H2O2 for 2 h induced a burst apoptosis that can be alleviated by N-acetyl cysteine (NAC) pretreatment, an anti-oxidant amino-acid derivative. Loss of mitochondria membrane potential (▵Ψm) was evaluated using confocal microscopy imaging and flow cytometry (FCM). H2O2 treatment induced a marked reduction of ▵Ψm, and the abrupt disappearance of ▵Ψm occurred within 5 minutes. These results indicate that H2O2 induces a rapid apoptosis via a mitochondrial pathway in rabbit chondrocytes.

  12. Iron dysregulation combined with aging prevents sepsis-induced apoptosis

    PubMed Central

    Javadi, Pardis; Buchman, Timothy G.; Stromberg, Paul E.; Turnbull, Isaiah R.; Vyas, Dinesh; Hotchkiss, Richard S.; Karl, Irene E.; Coopersmith, Craig M.

    2005-01-01

    Background Sepsis, iron loading and aging cause independent increases in gut epithelial and splenic apoptosis. It is unknown how their combination will affect apoptosis and systemic cytokine levels. Methods Hfe−/− mice (a murine homolog of hemochromatosis) abnormally accumulate iron in their tissues. Aged (24–26 months) or mature (16–18 months) Hfe−/− mice and wild type (WT) littermates were subjected to cecal ligation and puncture (CLP) or sham laparotomy. Intestine, spleen, and blood were harvested 24 hours later and assessed for apoptosis and cytokine levels. Results Gut epithelial and splenic apoptosis were low in both aged septic and sham Hfe−/− mice, regardless of the amount of iron in their diet. Mature septic WT mice had increased apoptosis compared to age-matched sham WT mice. Mature septic Hfe−/− mice had similar levels of intestinal cell death to age-matched septic WT mice but higher levels of splenic apoptosis. Apoptosis was significantly lower in septic aged Hfe−/− mice than septic mature Hfe−/− animals. Interleukin-6 was elevated in septic aged Hfe−/− mice compared to sham mice. Conclusions Although sepsis, chronic iron dysregulation, and aging each increase gut and splenic apoptosis, their combination yields cell death levels similar to sham animals despite the fact that aged Hfe−/− mice are able to mount an inflammatory response following CLP and mature Hfe−/− mice have elevated sepsis-induced apoptosis. Combining sepsis with two risk factors that ordinarily increase cell death and increase mortality in CLP yields an apoptotic response that could not have been predicted based upon each element in isolation. PMID:15921699

  13. GMI, an Immunomodulatory Protein from Ganoderma microsporum, Potentiates Cisplatin-Induced Apoptosis via Autophagy in Lung Cancer Cells.

    PubMed

    Hsin, I-Lun; Ou, Chu-Chyn; Wu, Ming-Fang; Jan, Ming-Shiou; Hsiao, Yi-Min; Lin, Ching-Hsiung; Ko, Jiunn-Liang

    2015-05-01

    Cisplatin-based therapy is common in the treatment of several types of cancers, including lung cancers. In our previous study, GMI, an immunomodulatory protein cloned from Ganoderma microsporum, induced a cytotoxic effect in lung cancer cells via autophagy. The aim of this study is to examine the role of GMI in enhancing cisplatin-mediated cell death. On the basis of MTT assay and Combination Index, GMI and cisplatin cotreatment induced a synergistic cytotoxic effect. GMI and cisplatin-induced apoptosis was determined by sub-G1, nuclear condensation, and annexin-V/propidium iodide analyses. On Western blot, expressions of γH2AX and cleaved forms of PARP, caspase-3, and caspase-7 were induced by combined treatment. Akt/mTOR pathway activity, LC3-II expression, and acidic vesicular organelle development demonstrated that cisplatin does not abolish GMI-mediated autophagy. Cyto-ID Green/hoechst 33342 double staining and time-dependent experiment indicated that GMI and cisplatin-treated A549 cells simultaneously express autophagosomes and apoptotic nuclei. To elucidate the role of autophagy in inducing apoptosis by GMI and cisplatin, chemical inhibitors and LC3 shRNA were used to inhibit autophagy. The results showed that 3-methyladenine decreases, while chloroquine increases GMI and cisplatin cotreatment-induced cleavage of caspase-7 and PARP. LC3 silencing abolished activation of apoptosis in A549 cells. Caspase inhibitors and caspase-7 silencing mitigated GMI and cisplatin-elicited cell viability inhibition and apoptosis. This is the first study to reveal the novel function of GMI in potentiating cisplatin-mediated apoptosis. GMI and cisplatin induce apoptosis via autophagy/caspase-7-dependent and survivin- and ERCC1-independent pathway. GMI may be a potential cisplatin adjuvant against lung cancer. PMID:25811903

  14. USMB-induced synergistic enhancement of aminoglycoside antibiotics in biofilms.

    PubMed

    Ronan, Evan; Edjiu, Narbeh; Kroukamp, Otini; Wolfaardt, Gideon; Karshafian, Raffi

    2016-07-01

    This study evaluated the effect of combining antibiotics with ultrasound and microbubbles (USMB) toward the eradication of biofilms. Pseudomonas aeruginosa PAO1 biofilms were treated with the antibiotics gentamicin sulfate or streptomycin sulfate, or a combination of USMB with the respective antibiotics. Biofilm structure was quantified using confocal laser scanning microscopy with COMSTAT analysis, while activity was measured as whole-biofilm CO2 production in a continuous-flow biofilm model. The combined antibiotic-USMB treatment significantly impacted biofilm biomass, thickness and surface roughness compared to antibiotics alone (p<0.05). USMB exposure caused the formation of craters (5-20μm in diameter) in the biofilms, and when combined with gentamicin, activity was significantly lower, compared to gentamicin, USMB or untreated controls, respectively. Interestingly, the CO2 production rate following combined streptomycin-USMB treatment was higher than after streptomycin alone, but significantly lower than USMB alone and untreated control. These results show strong evidence of a synergistic effect between antibiotics and USMB, although the varied response to different antibiotics emphasize the need to optimize the USMB exposure conditions to maximize this synergism and ultimately transfer this technology into clinical or industrial practice. PMID:27111871

  15. An increase of granulosa cell apoptosis mediates aqueous neem (Azadirachta indica) leaf extract-induced oocyte apoptosis in rat

    PubMed Central

    Tripathi, Anima; Shrivastav, Tulsidas G; Chaube, Shail K

    2013-01-01

    Objective: Neem plant (Azadirachta indica) has been extensively used in Ayurvedic system of medicine for female fertility regulation for a long time, but its mechanism of action remains poorly understood. Hence, the present study was aimed to determine whether an increase of granulosa cell apoptosis is associated with aqueous neem leaf extract (NLE)-induced oocyte apoptosis. Materials and Methods: Sexually immature female rats of 20 days old were fed NLE (50 mg/day) for 10 days and then subjected to superovulation induction protocol. The morphological changes in cumulus oocyte complexes (COCs), rate of oocyte apoptosis, hydrogen peroxide (H2O2), total nitrite, and cytochrome c concentrations, inducible nitric oxide synthase (iNOS), cytochrome c, p53, Bcl2 and Bax expressions, deoxyribonucleic acid (DNA) fragmentation, and estradiol 17β level in granulosa cells collected from preovulatory COCs were analyzed. Results: Aqueous NLE increased H2O2 concentration and decreased catalase activity, increased iNOS expression and total nitrite concentration, increased p53, Bax, and p53 expressions but decreased Bcl2 expression, increased cytochrome c concentration and induced DNA fragmentation in granulosa cells. An increased granulosa cell apoptosis resulted in reduced estradiol 17β concentration and induced apoptosis in ovulated oocytes. Conclusion: We conclude that aqueous NLE-induced granulosa cell apoptosis through the mitochondria-mediated pathway, reduced estradiol 17β concentration and induced apoptosis in ovulated oocytes. Thus, granulosa cell apoptosis mediates NLE-induced oocyte apoptosis during female fertility regulation in rat. PMID:23776837

  16. Combination treatment with triptolide and hydroxycamptothecin synergistically enhances apoptosis in A549 lung adenocarcinoma cells through PP2A-regulated ERK, p38 MAPKs and Akt signaling pathways.

    PubMed

    Meng, Guanmin; Wang, Wei; Chai, Kequn; Yang, Suwen; Li, Fangqiong; Jiang, Kai

    2015-03-01

    Lung cancer is the leading cause of cancer death worldwide. Recently, two plant-derived drugs triptolide (TP) and hydroxycamptothecin (HCPT) both have shown broad-spectrum anticancer activities. Our previous study documented that combination treatment with these two drugs acted more effectively than mono-therapy, however, the molecular basis underlying the synergistic cytotoxicity remains poorly understood. In this study, we aimed to clarify the molecular mechanism of TP/HCPT anticancer effect in A549 lung adenocarcinoma cells, by investigating the involvement of phosphatase 2A (PP2A) and PP2A-regulated mitogen-activated protein kinases (MAPKs) and Akt signaling pathways. The results showed that TP and HCPT synergistically exerted cytotoxicity in the growth of A549 cells. Combinatorial TP/HCPT treatment significantly enhanced the activation of caspase-3 and -9, Bax/Bcl-2 ratio, release of cytochrome c from mitochondrial and subsequent apoptosis. While the Akt survival pathway was inhibited, ERK and p38 MAPKs were dramatically activated. Furthermore, the activity of PP2A was significantly augmented. Regulation of p38, ERK and Akt by PP2A was demonstrated, by using a specific PP2A inhibitor okadaic acid (OA). Finally, pharmacological inhibitors OA, SB203580, SP600125 and PD98059 confirm the role of PP2A and its substrates ERK, p38 MAPK and Akt in mediating TP/HCPT-induced apoptosis. Taken together, this study provides the first evidence for a synergistic TP/HCPT anticancer activity in A549 cells and also supports a critical role of PP2A and PP2A-regulated signaling pathways, providing new insight into the mode of action of TP/HCPT in cancer therapy. PMID:25573072

  17. Combination treatment with triptolide and hydroxycamptothecin synergistically enhances apoptosis in A549 lung adenocarcinoma cells through PP2A-regulated ERK, p38 MAPKs and Akt signaling pathways

    PubMed Central

    MENG, GUANMIN; WANG, WEI; CHAI, KEQUN; YANG, SUWEN; LI, FANGQIONG; JIANG, KAI

    2015-01-01

    Lung cancer is the leading cause of cancer death worldwide. Recently, two plant-derived drugs triptolide (TP) and hydroxycamptothecin (HCPT) both have shown broad-spectrum anticancer activities. Our previous study documented that combination treatment with these two drugs acted more effectively than mono-therapy, however, the molecular basis underlying the synergistic cytotoxicity remains poorly understood. In this study, we aimed to clarify the molecular mechanism of TP/HCPT anticancer effect in A549 lung adenocarcinoma cells, by investigating the involvement of phosphatase 2A (PP2A) and PP2A-regulated mitogen-activated protein kinases (MAPKs) and Akt signaling pathways. The results showed that TP and HCPT synergistically exerted cytotoxicity in the growth of A549 cells. Combinatorial TP/HCPT treatment significantly enhanced the activation of caspase-3 and -9, Bax/Bcl-2 ratio, release of cytochrome c from mitochondrial and subsequent apoptosis. While the Akt survival pathway was inhibited, ERK and p38 MAPKs were dramatically activated. Furthermore, the activity of PP2A was significantly augmented. Regulation of p38, ERK and Akt by PP2A was demonstrated, by using a specific PP2A inhibitor okadaic acid (OA). Finally, pharmacological inhibitors OA, SB203580, SP600125 and PD98059 confirm the role of PP2A and its substrates ERK, p38 MAPK and Akt in mediating TP/HCPT-induced apoptosis. Taken together, this study provides the first evidence for a synergistic TP/HCPT anti-cancer activity in A549 cells and also supports a critical role of PP2A and PP2A-regulated signaling pathways, providing new insight into the mode of action of TP/HCPT in cancer therapy. PMID:25573072

  18. Simulation of synergistic effects on lateral PNP bipolar transistors induced by neutron and gamma irradiation

    NASA Astrophysics Data System (ADS)

    Wang, Chenhui; Bai, Xiaoyan; Chen, Wei; Yang, Shanchao; Liu, Yan; Jin, Xiaoming; Ding, Lili

    2015-10-01

    With semiconductor device simulation software TCAD, numerical simulations of ionizing/displacement synergistic effects on 6 kinds of lateral PNP bipolar transistors induced by the mixed irradiation of neutron and gamma are carried out by means of changing the minority carrier lifetimes, adding charged traps to the oxide layer and increasing the surface recombination velocity in Si/SiO2 interface. The results indicate that ionizing/displacement synergistic effects on the lateral PNP bipolar transistors are not a simple sum of total ionizing dose effects and displacement effects, and total ionizing dose effects can enhance neutron displacement damages, leading to greater gain degradation. The physical mechanisms of ionizing/displacement synergistic effects are analyzed based on the results. The positive charge in the oxide layer and Si/SiO2 interface traps induced by gamma irradiation can enhance the recombination processes of carriers in the bulk defects induced by neutron irradiation, and this is the main cause of ionizing/displacement synergistic effects on the lateral PNP bipolar transistors.

  19. Cystamine induces AIF-mediated apoptosis through glutathione depletion.

    PubMed

    Cho, Sung-Yup; Lee, Jin-Haeng; Ju, Mi-kyeong; Jeong, Eui Man; Kim, Hyo-Jun; Lim, Jisun; Lee, Seungun; Cho, Nam-Hyuk; Park, Hyun Ho; Choi, Kihang; Jeon, Ju-Hong; Kim, In-Gyu

    2015-03-01

    Cystamine and its reduced form cysteamine showed protective effects in various models of neurodegenerative disease, including Huntington's disease and Parkinson's disease. Other lines of evidence demonstrated the cytotoxic effect of cysteamine on duodenal mucosa leading to ulcer development. However, the mechanism for cystamine cytotoxicity remains poorly understood. Here, we report a new pathway in which cystamine induces apoptosis by targeting apoptosis-inducing factor (AIF). By screening of various cell lines, we observed that cystamine and cysteamine induce cell death in a cell type-specific manner. Comparison between cystamine-sensitive and cystamine-resistant cell lines revealed that cystamine cytotoxicity is not associated with unfolded protein response, reactive oxygen species generation and transglutaminase or caspase activity; rather, it is associated with the ability of cystamine to trigger AIF nuclear translocation. In cystamine-sensitive cells, cystamine suppresses the levels of intracellular glutathione by inhibiting γ-glutamylcysteine synthetase expression that triggers AIF translocation. Conversely, glutathione supplementation completely prevents cystamine-induced AIF translocation and apoptosis. In rats, cysteamine administration induces glutathione depletion and AIF translocation leading to apoptosis of duodenal epithelium. These results indicate that AIF translocation through glutathione depletion is the molecular mechanism of cystamine toxicity, and provide important implications for cystamine in the neurodegenerative disease therapeutics as well as in the regulation of AIF-mediated cell death. PMID:25549939

  20. (+)-Catechin protects dermal fibroblasts against oxidative stress-induced apoptosis

    PubMed Central

    2014-01-01

    Background Oxidative stress has been suggested as a mechanism underlying skin aging, as it triggers apoptosis in various cell types, including fibroblasts, which play important roles in the preservation of healthy, youthful skin. Catechins, which are antioxidants contained in green tea, exert various actions such as anti-inflammatory, anti-bacterial, and anti-cancer actions. In this study, we investigated the effect of (+)-catechin on apoptosis induced by oxidative stress in fibroblasts. Methods Fibroblasts (NIH3T3) under oxidative stress induced by hydrogen peroxide (0.1 mM) were treated with either vehicle or (+)-catechin (0–100 μM). The effect of (+)-catechin on cell viability, apoptosis, phosphorylation of c-Jun terminal kinases (JNK) and p38, and activation of caspase-3 in fibroblasts under oxidative stress were evaluated. Results Hydrogen peroxide induced apoptotic cell death in fibroblasts, accompanied by induction of phosphorylation of JNK and p38 and activation of caspase-3. Pretreatment of the fibroblasts with (+)-catechin inhibited hydrogen peroxide-induced apoptosis and reduced phosphorylation of JNK and p38 and activation of caspase-3. Conclusion (+)-Catechin protects against oxidative stress-induced cell death in fibroblasts, possibly by inhibiting phosphorylation of p38 and JNK. These results suggest that (+)-catechin has potential as a therapeutic agent for the prevention of skin aging. PMID:24712558

  1. Lysophosphatidic acid induces necrosis and apoptosis in hippocampal neurons.

    PubMed

    Holtsberg, F W; Steiner, M R; Keller, J N; Mark, R J; Mattson, M P; Steiner, S M

    1998-01-01

    A diverse body of evidence indicates a role for the lipid biomediator lysophosphatidic acid (LPA) in the CNS. This study identifies and characterizes the induction of neuronal death by LPA. Treatment of cultured hippocampal neurons from embryonic rat brains with 50 microM LPA resulted in neuronal necrosis, as determined morphologically and by the release of lactate dehydrogenase. A concentration of LPA as low as 10 microM led to the release of lactate dehydrogenase. In contrast, treatment of neurons with 0.1 or 1.0 microM LPA resulted in apoptosis, as determined by chromatin condensation. In addition, neuronal death induced by 1 microM LPA was characterized as apoptotic on the basis of terminal dUTP nick end-labeling (TUNEL) staining, externalization of phosphatidylserine, and protection against chromatin condensation, TUNEL staining, and phosphatidylserine externalization by treatment with N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethyl ketone, a broad-spectrum inhibitor of caspases, i.e., members of the interleukin-1beta converting enzyme family. Studies with antagonists of ionotropic glutamate receptors did not indicate a significant role for these receptors in apoptosis induced by 1 microM LPA. LPA (1 microM) also induced a decrease in mitochondrial membrane potential. Moreover, pretreatment of neurons with cyclosporin A protected against the LPA-induced decrease in mitochondrial membrane potential and neuronal apoptosis. Thus, LPA, at pathophysiological levels, can induce neuronal apoptosis and could thereby participate in neurodegenerative disorders. PMID:9422348

  2. Hydrogen peroxide-induced apoptosis in human gingival fibroblasts.

    PubMed

    Gutiérrez-Venegas, Gloria; Guadarrama-Solís, Adriana; Muñoz-Seca, Carmen; Arreguín-Cano, Juan Antonio

    2015-01-01

    In the process of bleaching vital, discolored teeth, low concentrations of hydrogen peroxide (H2O2) are effective alternatives to heat-activated 30% H2O2. However, interest has been expressed in the assessment of pathological effects of long-term exposure to bleaching agents such as irritation and ulceration of the gingival or other soft tissues. The aim of the present study was to determine the effect of hydrogen peroxide on apoptosis in human gingival fibroblasts (HGF). Cytochrome c, Bcl-2, Bax, Bid and caspase-3 protein expression were detected by Western blotting. HGF cell apoptosis induced by H2O2 was both dose and time dependent. The addition of H2O2 resulted in the release of cytochrome c to the cytosol, and an increase of Caspase-3 cleavage. Data suggest that oxidative stress-induced apoptosis in HGF is intrinsic pathway involved the release of apoptotic signal from mitochondria. PMID:26884825

  3. Hydrogen peroxide-induced apoptosis in human gingival fibroblasts

    PubMed Central

    Gutiérrez-Venegas, Gloria; Guadarrama-Solís, Adriana; Muñoz-Seca, Carmen; Arreguín-Cano, Juan Antonio

    2015-01-01

    In the process of bleaching vital, discolored teeth, low concentrations of hydrogen peroxide (H2O2) are effective alternatives to heat-activated 30% H2O2. However, interest has been expressed in the assessment of pathological effects of long-term exposure to bleaching agents such as irritation and ulceration of the gingival or other soft tissues. The aim of the present study was to determine the effect of hydrogen peroxide on apoptosis in human gingival fibroblasts (HGF). Cytochrome c, Bcl-2, Bax, Bid and caspase-3 protein expression were detected by Western blotting. HGF cell apoptosis induced by H2O2 was both dose and time dependent. The addition of H2O2 resulted in the release of cytochrome c to the cytosol, and an increase of Caspase-3 cleavage. Data suggest that oxidative stress-induced apoptosis in HGF is intrinsic pathway involved the release of apoptotic signal from mitochondria. PMID:26884825

  4. EF24 induces ROS-mediated apoptosis via targeting thioredoxin reductase 1 in gastric cancer cells

    PubMed Central

    Chen, Weiqian; Chen, Xi; Ying, Shilong; Feng, Zhiguo; Chen, Tongke; Ye, Qingqing; Wang, Zhe; Qiu, Chenyu; Yang, Shulin; Liang, Guang

    2016-01-01

    Gastric cancer (GC) is one of the leading causes of cancer mortality in the world, and finding novel agents for the treatment of advanced gastric cancer is of urgent need. Diphenyl difluoroketone (EF24), a molecule having structural similarity to curcumin, exhibits potent anti-tumor activities by arresting cell cycle and inducing apoptosis. Although EF24 demonstrates potent anticancer efficacy in numerous types of human cancer cells, the cellular targets of EF24 have not been fully defined. We report here that EF24 may interact with the thioredoxin reductase 1 (TrxR1), an important selenocysteine (Sec)-containing antioxidant enzyme, to induce reactive oxygen species (ROS)-mediated apoptosis in human gastric cancer cells. By inhibiting TrxR1 activity and increasing intracellular ROS levels, EF24 induces a lethal endoplasmic reticulum stress in human gastric cancer cells. Importantly, knockdown of TrxR1 sensitizes cells to EF24 treatment. In vivo, EF24 treatment markedly reduces the TrxR1 activity and tumor cell burden, and displays synergistic lethality with 5-FU against gastric cancer cells. Targeting TrxR1 with EF24 thus discloses a previously unrecognized mechanism underlying the biological activity of EF24, and reveals that TrxR1 is a good target for gastric cancer therapy. PMID:26919110

  5. EF24 induces ROS-mediated apoptosis via targeting thioredoxin reductase 1 in gastric cancer cells.

    PubMed

    Zou, Peng; Xia, Yiqun; Chen, Weiqian; Chen, Xi; Ying, Shilong; Feng, Zhiguo; Chen, Tongke; Ye, Qingqing; Wang, Zhe; Qiu, Chenyu; Yang, Shulin; Liang, Guang

    2016-04-01

    Gastric cancer (GC) is one of the leading causes of cancer mortality in the world, and finding novel agents for the treatment of advanced gastric cancer is of urgent need. Diphenyl difluoroketone (EF24), a molecule having structural similarity to curcumin, exhibits potent anti-tumor activities by arresting cell cycle and inducing apoptosis. Although EF24 demonstrates potent anticancer effïcacy in numerous types of human cancer cells, the cellular targets of EF24 have not been fully defined. We report here that EF24 may interact with the thioredoxin reductase 1 (TrxR1), an important selenocysteine (Sec)-containing antioxidant enzyme, to induce reactive oxygen species (ROS)-mediated apoptosis in human gastric cancer cells. By inhibiting TrxR1 activity and increasing intracellular ROS levels, EF24 induces a lethal endoplasmic reticulum stress in human gastric cancer cells. Importantly, knockdown of TrxR1 sensitizes cells to EF24 treatment. In vivo, EF24 treatment markedly reduces the TrxR1 activity and tumor cell burden, and displays synergistic lethality with 5-FU against gastric cancer cells. Targeting TrxR1 with EF24 thus discloses a previously unrecognized mechanism underlying the biological activity of EF24, and reveals that TrxR1 is a good target for gastric cancer therapy. PMID:26919110

  6. Eribulin synergizes with Polo-like kinase 1 inhibitors to induce apoptosis in rhabdomyosarcoma.

    PubMed

    Stehle, Angelika; Hugle, Manuela; Fulda, Simone

    2015-08-28

    Eribulin, a novel microtubule-interfering drug, was recently shown to exhibit high antitumor activity in vivo against various pediatric cancers. Here, we identify a novel synthetic lethal interaction of Eribulin together with Polo-like kinase 1 (PLK1) inhibitors against rhabdomyosarcoma (RMS) in vitro and in vivo. Eribulin and the PLK1 inhibitor BI 2536 at subtoxic concentrations synergize to induce apoptosis in RMS cells as confirmed by calculation of combination index (CI). Also, Eribulin/BI 2536 co-treatment is significantly more effective than monotherapy to reduce cell viability and inhibit colony formation of RMS cells. Similarly, Eribulin and BI 2536 act in concert to trigger apoptosis in a primary, patient-derived ARMS culture, underscoring the clinical relevance of this combination. Importantly, Eribulin and BI 2536 cooperate to suppress tumor growth in an in vivo model of RMS. On molecular grounds, Eribulin/BI 2536 co-treatment causes profound mitotic arrest, which is critically required for synergism, since inhibition of mitotic arrest by CDK1 inhibitor RO-3306 abolishes Eribulin/BI 2536-mediated apoptosis. Eribulin and BI 2536 cooperate to activate caspase-9, -3 and -8, which is necessary for apoptosis induction, since the broad-range caspase inhibitor N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (zVAD.fmk) reduces Eribulin/BI 2536-induced apoptosis significantly, yet partially. Intriguingly, knockdown of endonuclease G (ENDOG) also significantly inhibits Eribulin/BI 2536-triggered apoptosis, demonstrating the involvement of both caspase-dependent and -independent effector pathways. Synergistic induction of apoptosis is similarly found for Eribulin/BI 2536 co-treatment in neuroblastoma cells and for the combination of vincristine (another antimicrotubule chemotherapeutic) with Poloxin (another PLK1 inhibitor), thus pointing to a broader significance of this concomitant microtubule- and PLK1-targeting strategy for pediatric oncology. In

  7. Glutathione peroxidase-1 protects from CD95-induced apoptosis.

    PubMed

    Gouaze, Valerie; Andrieu-Abadie, Nathalie; Cuvillier, Olivier; Malagarie-Cazenave, Sophie; Frisach, Marie-Francoise; Mirault, Marc-Edouard; Levade, Thierry

    2002-11-01

    Through the induction of apoptosis, CD95 plays a crucial role in the immune response and the elimination of cancer cells. Ligation of CD95 receptor activates a complex signaling network that appears to implicate the generation of reactive oxygen species (ROS). This study investigated the place of ROS production in CD95-mediated apoptosis and the role of the antioxidant enzyme glutathione peroxidase-1 (GPx1). Anti-CD95 antibodies triggered an early generation of ROS in human breast cancer T47D cells that was blocked by overexpression of GPx1 and inhibition of initiator caspase activation. Enforced expression of GPx1 also resulted in inhibition of CD95-induced effector caspase activation, DNA fragmentation, and apoptotic cell death. Resistance to CD95-mediated apoptosis was not due to an increased expression of anti-apoptotic molecules and could be reversed by glutathione-depleting agents. In addition, whereas the anti-apoptotic protein Bcl-xL prevented CD95-induced apoptosis in MCF-7 cells, it did not inhibit the early ROS production. Moreover, Bcl-xL but not GPx1 overexpression could suppress the staurosporine-induced late generation of ROS and subsequent cell death. Altogether, these findings suggest that GPx1 functions upstream of the mitochondrial events to inhibit the early ROS production and apoptosis induced by CD95 ligation. Finally, transgenic mice overexpressing GPx1 were partially protected from the lethal effect of anti-CD95, underlying the importance of peroxide formation (and GPx1) in CD95-triggered apoptosis. PMID:12221075

  8. Taurine induces the apoptosis of breast cancer cells by regulating apoptosis-related proteins of mitochondria.

    PubMed

    Zhang, Xiali; Lu, Hongfei; Wang, Yibing; Liu, Chunju; Zhu, Weifeng; Zheng, Shuangyan; Wan, Fusheng

    2015-01-01

    Taurine (Tau), the most abundant free amino acid in humans has numerous potential health benefits through its antioxidant and anti-inflammatory properties. However, limited studies have assessed its effect on tumors and the antitumor mechanism remains unknown. The present study investigated the cellular and molecular changes induced by Tau, leading to the induction of apoptosis in human breast cancer cell lines MCF-7 and MDA-MB-231. MCF-7 is p53 proficient (p53+/+) and MDA-MB-231 is a p53 null mutant (p53-/-). Cell proliferation and viability were assessed by MTT. Flow cytometry and hoechst33342 fluorescent staining were employed to detect apoptosis. Spectrophotometry was used to detect caspase-3 activity. Reverse transcription-polymerase chain reaction and western blot analysis were used to detect the levels of mRNA and proteins of p53-upregulated modulator of apoptosis (PUMA), Bax and Bcl-2. Finally, the affect of Tau on the growth of MDA-MB-231-cell-nude mice xenografts was examined. In the study, Tau inhibited growth and induced apoptosis of the two cell lines in a concentration- and time-dependent manner. Notably, the inhibitory effect of Tau on p53-/- cancer cells was clearly significant compared to the p53+/+ cancer cells. Further studies showed that Tau promoted apoptosis in human breast cancer cells and inhibited the growth of tumor in nude mice by inducing the expression of PUMA, which further up- and downregulated the expression of Bax and Bcl-2 protein, giving rise to increased activation of caspase-3. Collectively, these results indicate that Tau is a potent candidate for the chemotherapy of breast cancer through increasing the PUMA expression independent of p53 status. PMID:25395275

  9. The human immunodeficiency virus type 1 tat protein enhances Cryptosporidium parvum-induced apoptosis in cholangiocytes via a Fas ligand-dependent mechanism.

    PubMed

    O'Hara, Steven P; Small, Aaron J; Nelson, Jeremy B; Badley, Andrew D; Chen, Xian-Ming; Gores, Gregory J; Larusso, Nicholas F

    2007-02-01

    While Cryptosporidium parvum infection of the intestine has been reported in both immunocompetent and immunocompromised individuals, biliary infection is seen primarily in adult AIDS patients and is associated with development of AIDS cholangiopathy. However, the mechanisms of pathogen-induced AIDS cholangiopathy remain unclear. Since we previously demonstrated that the Fas/Fas ligand (FasL) system is involved in paracrine-mediated C. parvum cytopathicity in cholangiocytes, we also tested the potential synergistic effects of human immunodeficiency virus type 1 (HIV-1) transactivator of transcription (Tat)-mediated FasL regulation on C. parvum-induced apoptosis in cholangiocytes by semiquantitative reverse transcription-PCR, immunoblotting, immunofluorescence analysis, and immunogold electron microscopy. H69 cells do not express CXCR4 and CCR5, which are receptors required for direct HIV-1 viral infection. However, recombinant biologically active HIV-1-associated Tat protein increased FasL expression in the cytoplasm of cholangiocytes without a significant increase in apoptosis. We found that C. parvum-induced apoptosis was associated with translocation of intracellular FasL to the cell membrane surface and release of full-length FasL from infected H69 cells. Tat significantly (P < 0.05) increased C. parvum-induced apoptosis in bystander cells in a dose-dependent manner. Moreover, Tat enhanced both C. parvum-induced FasL membrane translocation and release of full-length FasL. In addition, the FasL neutralizing antibody NOK-1 and the caspase-8 inhibitor Z-IETD-fmk both blocked C. parvum-induced apoptosis in cholangiocytes. The data demonstrated that HIV-1 Tat enhances C. parvum-induced cholangiocyte apoptosis via a paracrine-mediated, FasL-dependent mechanism. Our results suggest that concurrent active HIV replication, with associated production of Tat protein, and C. parvum infection synergistically increase cholangiocyte apoptosis and thus jointly contribute to

  10. MG132, a proteasome inhibitor, induces apoptosis in tumor cells.

    PubMed

    Guo, Na; Peng, Zhilan

    2013-03-01

    The balance between cell proliferation and apoptosis is critical for normal development and for the maintenance of homeostasis in adult organisms. Disruption of this balance has been implicated in a large number of disease processes, ranging from autoimmunity and neurodegenerative disorders to cancer. The ubiquitin-proteasome pathway, responsible for mediating the majority of intracellular proteolysis, plays a crucial role in the regulation of many normal cellular processes, including the cell cycle, differentiation and apoptosis. Apoptosis in cancer cells is closely connected with the activity of ubiquitin-proteasome pathway. The peptide-aldehyde proteasome inhibitor MG132 (carbobenzoxyl-L-leucyl-L-leucyl-L-leucine) induces the apoptosis of cells by a different intermediary pathway. Although the pathway of induction of apoptosis is different, it plays a crucial role in anti-tumor treatment. There are many cancer-related molecules in which the protein levels present in cells are regulated by a proteasomal pathway; for example, tumor inhibitors (P53, E2A, c-Myc, c-Jun, c-Fos), transcription factors (transcription factor nuclear factor-kappa B, IκBα, HIFI, YYI, ICER), cell cycle proteins (cyclin A and B, P27, P21, IAP1/3), MG132 induces cell apoptosis through formation of reactive oxygen species or the upregulation and downregulation of these factors, which is ultimately dependent upon the activation of the caspase family of cysteine proteases. In this article we review the mechanism of the induction of apoptosis in order to provide information required for research. PMID:22897979

  11. Salmonella typhimurium Invasion Induces Apoptosis in Infected Macrophages

    NASA Astrophysics Data System (ADS)

    Monack, Denise M.; Raupach, Barbel; Hromockyj, Alexander E.; Falkow, Stanley

    1996-09-01

    Invasive Salmonella typhimurium induces dramatic cytoskeletal changes on the membrane surface of mammalian epithelial cells and RAW264.7 macrophages as part of its entry mechanism. Noninvasive S. typhimurium strains are unable to induce this membrane ruffling. Invasive S. typhimurium strains invade RAW264.7 macrophages in 2 h with 7- to 10-fold higher levels than noninvasive strains. Invasive S. typhimurium and Salmonella typhi, independent of their ability to replicate intracellularly, are cytotoxic to RAW264.7 macrophages and, to a greater degree, to murine bone marrow-derived macrophages. Here, we show that the macrophage cytotoxicity mediated by invasive Salmonella is apoptosis, as shown by nuclear morphology, cytoplasmic vacuolization, and host cell DNA fragmentation. S. typhimurium that enter cells causing ruffles but are mutant for subsequent intracellular replication also initiate host cell apoptosis. Mutant S. typhimurium that are incapable of inducing host cell membrane ruffling fail to induce apoptosis. The activation state of the macrophage plays a significant role in the response of macrophages to Salmonella invasion, perhaps indicating that the signal or receptor for initiating programmed cell death is upregulated in activated macrophages. The ability of Salmonella to promote apoptosis may be important for the initiation of infection, bacterial survival, and escape of the host immune response.

  12. Sustained adenosine exposure causes lung endothelial apoptosis: a possible contributor to cigarette smoke-induced endothelial apoptosis and lung injury

    PubMed Central

    Sakhatskyy, Pavlo; Newton, Julie; Shamirian, Paul; Hsiao, Vivian; Curren, Sean; Gabino Miranda, Gustavo Andres; Pedroza, Mesias; Blackburn, Michael R.; Rounds, Sharon

    2013-01-01

    Pulmonary endothelial cell (EC) apoptosis has been implicated in the pathogenesis of emphysema. Cigarette smoke (CS) causes lung EC apoptosis and emphysema. In this study, we show that CS exposure increased lung tissue adenosine levels in mice, an effect associated with increased lung EC apoptosis and the development of emphysema. Adenosine has a protective effect against apoptosis via adenosine receptor-mediated signaling. However, sustained elevated adenosine increases alveolar cell apoptosis in adenosine deaminase-deficient mice. We established an in vitro model of sustained adenosine exposure by incubating lung EC with adenosine in the presence of an adenosine deaminase inhibitor, deoxycoformicin. We demonstrated that sustained adenosine exposure caused lung EC apoptosis via nucleoside transporter-facilitated intracellular adenosine uptake, subsequent activation of p38 and JNK in mitochondria, and ultimately mitochondrial defects and activation of the mitochondria-mediated intrinsic pathway of apoptosis. Our results suggest that sustained elevated adenosine may contribute to CS-induced lung EC apoptosis and emphysema. Our data also reconcile the paradoxical effects of adenosine on apoptosis, demonstrating that prolonged exposure causes apoptosis via nucleoside transporter-mediated intracellular adenosine signaling, whereas acute exposure protects against apoptosis via activation of adenosine receptors. Inhibition of adenosine uptake may become a new therapeutic target in treatment of CS-induced lung diseases. PMID:23316066

  13. Chemotherapeutic-Induced Apoptosis – A Phenotype for Pharmacogenomics Studies

    PubMed Central

    Wen, Yujia; Gorsic, Lidija K.; Wheeler, Heather E.; Ziliak, Dana M.; Huang, R. Stephanie; Dolan, M. Eileen

    2011-01-01

    Lymphoblastoid cell lines have been used as a model system to identify genetic determinants of chemotherapeutic-induced cytotoxicity, a phenotype thought to represent cellular sensitivity to drug. However, cytotoxicity is a broad measurement encompassing cell cycle inhibition as well as cell death (apoptotic and non-apoptotic). We evaluated caspase 3/7 mediated cellular apoptosis with six chemotherapeutic agents: 5′-deoxy-fluorouridine, pemetrexed, cytarabine, paclitaxel, carboplatin and cisplatin. Using monozygotic twin pair and sibling pair lymphoblastoid cell lines, we identified conditions for measurement of caspase activity. Although treatment with 5′-deoxy-fluorouridine and pemetrexed for up to 24 h did not result in significant apoptosis or inter-individual variation in caspase dependent cell death; paclitaxel, cisplatin, carboplain and cytarabine treatment for 24 h resulted in 9.4, 9.1, 7.0 and 6.0 fold increases in apoptosis relative to control, respectively. There was a weak correlation between caspase activity and cytotoxicity (r2=0.03 to 0.29) demonstrating that cytotoxicity and apoptosis are two distinct phenotypes that may produce independent genetic associations. Estimated heritability (h2) for apoptosis was 0.57 and 0.29 for cytarabine (5 μM and 40 μM respectively), 0.22 for paclitaxel (12.5 nM), and 0.34 for cisplatin (5 μM). The HapMap CEU panel of lymphoblastoid cell lines (n = 77) were evaluated for sensitivity to cisplatin followed by genome wide association studies with over 2 million SNPs at p < 0.001. We identified a significant enrichment of cisplatin-induced apoptosis SNPs within the significant cisplatin induced cytotoxicity SNPs and an enrichment of expression quantitative trait loci. PMID:21642893

  14. Ambrisentan and tadalafil synergistically relax endothelin-induced contraction of rat pulmonary arteries.

    PubMed

    Liang, Faquan; Yang, Suya; Yao, Lina; Belardinelli, Luiz; Shryock, John

    2012-03-01

    Endothelin receptor antagonists and phosphodiesterase type 5 inhibitors are used to treat pulmonary arterial hypertension. We tested the hypothesis that a selective endothelin type A receptor antagonist (ambrisentan) and a phosphodiesterase type 5 inhibitor (tadalafil) may act synergistically to relax endothelin-constricted pulmonary arteries. Rat isolated intrapulmonary arterial rings contracted with 8 nmol/L endothelin-1 were relaxed by 10 nmol/L ambrisentan and 30 nmol/L tadalafil alone by 26±3% and 21±1%, respectively, whereas both drugs in combination acted synergistically to relax arterial rings by 83±6%. The nonselective endothelin type A and B receptor antagonists bosentan (100 nmol/L) and macitentan (30 nmol/L) alone relaxed endothelin-contracted rings by 30±5% and 24±3%, respectively. Combinations of 30 nmol/L tadalafil with 100 nmol/L bosentan or 30 nmol/L macitentan relaxed endothelin-contracted rings by 53±5% or 46±7%, respectively; these values are similar to the calculated sums of the individual effects of these compounds. Denudation of endothelium from pulmonary arterial rings abolished the vasodilator response to 30 nmol/L tadalafil and the synergistic vasorelaxant effect of tadalafil with ambrisentan. In the presence of 1 μmol/L BQ-788, a selective endothelin type B receptor antagonist, the vasorelaxant effects of 10 nmol/L ambrisentan and 30 nmol/L tadalafil were additive but not synergistic. These data can be interpreted to suggest that ambrisentan and tadalafil synergistically inhibit endothelin-1-induced constriction of rat intrapulmonary arteries and that endothelin type B receptors in endothelium are necessary to enable a synergistic vasorelaxant effect of the drug combination. PMID:22311911

  15. Capsaicin induces apoptosis in PC12 cells through ER stress.

    PubMed

    Krizanova, Olga; Steliarova, Iveta; Csaderova, Lucia; Pastorek, Michal; Hudecova, Sona

    2014-02-01

    Capsaicin, the pungent agent in chili peppers, has been shown to act as a tumor-suppressor in cancer. In our previous study, capsaicin was shown to induce apoptosis in the rat pheochromocytoma cell line (PC12 cells). Thus, the aim of the present study was to determine the potential mechanism by which capsaicin induces apoptosis. We treated PC12 cells with 50, 100 and 500 µM capsaicin and measured the reticular calcium content and expression of the reticular calcium transport systems. These results were correlated with endoplasmic reticulum (ER) stress markers CHOP, ATF4 and X-box binding protein 1 (XBP1), as well as with apoptosis induction. We observed that capsaicin decreased reticular calcium in a concentration-dependent manner. Simultaneously, expression levels of the sarco/endoplasmic reticulum pump and ryanodin receptor of type 2 were modified. These changes were accompanied by increased ER stress, as documented by increased stress markers. Thus, from these results we propose that in PC12 cells capsaicin induces apoptosis through increased ER stress. PMID:24337105

  16. Lipopolysaccharide-Induced Apoptosis of Astrocytes: Therapeutic Intervention by Minocycline.

    PubMed

    Sharma, Arpita; Patro, Nisha; Patro, Ishan K

    2016-05-01

    Astrocytes are most abundant glial cell type in the brain and play a main defensive role in central nervous system against glutamate-induced toxicity by virtue of numerous transporters residing in their membranes and an astrocyte-specific enzyme glutamine synthetase (GS). In view of that, a dysregulation in the astrocytic activity following an insult may result in glutamate-mediated toxicity accompanied with astrocyte and microglial activation. The present study suggests that the lipopolysaccharide (LPS)-induced inflammation results in significant astrocytic apoptosis compared to other cell types in hippocampus and minocycline could not efficiently restrict the glutamate-mediated toxicity and apoptosis of astrocytes. Upon LPS exposure 76 % astrocytes undergo degeneration followed by 44 % oligodendrocytes, 26 % neurons and 10 % microglia. The pronounced astrocytic apoptosis resulted from the LPS-induced glutamate excitotoxicity leading to their hyperactivation as evident from their hypertrophied morphology, glutamate transporter 1 upregulation and downregulation of GS. Therapeutic minocycline treatment to LPS-infused rats efficiently restricted the inflammatory response and degeneration of other cell types but could not significantly combat with the apoptosis of astrocytes. Our study demonstrates a novel finding on cellular degeneration in the hippocampus revealing more of astrocytic death and suggests a more careful consideration on the protective efficacy of minocycline. PMID:26188416

  17. Phytoconstituents as apoptosis inducing agents: strategy to combat cancer.

    PubMed

    Kumar, Manish; Kaur, Varinder; Kumar, Subodh; Kaur, Satwinderjeet

    2016-08-01

    Advancement in the field of cancer molecular biology has aided researchers to develop various new chemopreventive agents which can target cancer cells exclusively. Cancer chemopreventive agents have proficiency to inhibit, reverse and delay process of carcinogenesis during its early and later course. Chemopreventive agents can act as antioxidative, antimutagenic/antigenotoxic, anti-inflammatory agents or via aiming various molecular targets in a cell to induce cell death. Apoptosis is a kind of cell death which shows various cellular morphological alterations such as cell shrinkage, blebbing of membrane, chromatin condensation, DNA fragmentation, formation of apoptotic bodies etc. Nowadays, apoptosis is being one of the new approaches for the identification and development of novel anticancer therapies. For centuries, plants are known to play part in daily routine from providing food to management of human health. In the last two decades, diverse phytochemicals and various botanical formulations have been characterized as agents that possess potential to execute cancer cells via inducing apoptosis. Data obtained from the research carried out globally pointed out that natural products are the potential candidates which have capability to combat cancer. In the present review, we surveyed literature on natural products which throws light on the mechanism through which these phytochemicals induce apoptosis in cancer cells. PMID:26239338

  18. Synergistic neurotoxicity induced by methylmercury and quercetin in mice

    PubMed Central

    Martins, Roberta de P.; Braga, Hugo de C.; da Silva, Aline P.; Dalmarco, Juliana B.; de Bem, Andreza F.; dos Santos, Adair Roberto S.; Dafre, Alcir L.; Pizzolatti, Moacir G.; Latini, Alexandra; Aschner, Michael; Farina, Marcelo

    2010-01-01

    Methylmercury (MeHg) is a highly neurotoxic pollutant, whose mechanisms of toxicity are related to its pro-oxidative properties. A previous report showed under in vivo conditions the neuroprotective effects of plants of the genus Polygala against MeHg-induced neurotoxicity. Moreover, the flavonoid quercetin, isolated from Polygala sabulosa, displayed beneficial effects against MeHg-induced oxidative damage under in vitro conditions. In this study, we sought for potential beneficial effects of quercetin against the neurotoxicity induced by MeHg in Swiss female mice. Animals were divided into six experimental groups: control, quercetin low dose (5 mg/Kg), quercetin high dose (50 mg/Kg), MeHg (40 mg/L, in tap water), MeHg + quercetin low dose, and MeHg + quercetin high dose. After the treatment (21 days), a significant motor deficit was observed in MeHg + quercetin groups. Biochemical parameters related to oxidative stress showed that the simultaneous treatment with quercetin and MeHg caused a higher cerebellar oxidative damage when compared to the individual exposures. MeHg plus quercetin elicited a higher cerebellar lipid peroxidation than MeHg or quercetin alone. The present results indicate that under in vivo conditions quercetin and MeHg cause additive pro-oxidative effects toward the mice cerebellum and that such phenomenon is associated with the observed motor deficit. PMID:19141311

  19. Determinants of PDT-induced apoptosis

    NASA Astrophysics Data System (ADS)

    Kessel, David; Luo, Yu; Kim, Hyeong-Reh C.

    2000-03-01

    Photodynamic therapy can initiate cell death by apoptosis or necrosis. Using agents with known patterns of sub-cellular localization, we examined the correlation between sites of photodamage and the mode of cell death, using murine leukemia cells in vitro. Mitochondrial or mitochondrial/lysosomal photodamage caused the rapid release of cytochrome c. This effect was not temperature sensitive, and could be demonstrated immediately after irradiation of photosensitized cells at 10 degrees C. Subsequent warming to 37 degrees C led to a rapid apoptotic response, consistent with the known ability of cytochrome c to trigger the activation of caspase-3. In contrast, lysosomal or lysosomal/membrane photodamage resulted in the release of cathepsins and other proteolytic enzymes. A subsequent incubation at 37 degrees C resulted in mitochondrial degradation, leading to loss of cytochrome c within 30 min. The apoptotic response was both delayed and incomplete, with many dead cells not exhibiting an apoptotic morphology. The latter outcome was traced to photodamage to procaspase-3, an effect not observed with sensitizers that caused mainly mitochondrial photodamage. Studies in a cell-free system demonstrated that agents with lysosomal and/or membrane targets could bring about photoinactivation of caspase-3. These result are consistent with the proposal that photodynamic therapy can both activate and inactivate components of the apoptotic process.

  20. Interleukin-7 and Toll-Like Receptor 7 Induce Synergistic B Cell and T Cell Activation

    PubMed Central

    Bikker, Angela; Kruize, Aike A.; van der Wurff-Jacobs, Kim M. G.; Peters, Rogier P.; Kleinjan, Marije; Redegeld, Frank; de Jager, Wilco; Lafeber, Floris P. J. G.; van Roon, Joël A. G.

    2014-01-01

    Objectives To investigate the potential synergy of IL-7-driven T cell-dependent and TLR7-mediated B cell activation and to assess the additive effects of monocyte/macrophages in this respect. Methods Isolated CD19 B cells and CD4 T cells from healthy donors were co-cultured with TLR7 agonist (TLR7A, Gardiquimod), IL-7, or their combination with or without CD14 monocytes/macrophages (T/B/mono; 1 : 1 : 0,1). Proliferation was measured using 3H-thymidine incorporation and Ki67 expression. Activation marker (CD19, HLA-DR, CD25) expression was measured by FACS analysis. Immunoglobulins were measured by ELISA and release of cytokines was measured by Luminex assay. Results TLR7-induced B cell activation was not associated with T cell activation. IL-7-induced T cell activation alone and together with TLR7A synergistically increased numbers of both proliferating (Ki67+) B cells and T cells, which was further increased in the presence of monocytes/macrophages. This was associated by up regulation of activation markers on B cells and T cells. Additive or synergistic induction of production of immunoglobulins by TLR7 and IL-7 was associated by synergistic induction of T cell cytokines (IFNγ, IL-17A, IL-22), which was only evident in the presence of monocytes/macrophages. Conclusions IL-7-induced CD4 T cell activation and TLR7-induced B cell activation synergistically induce T helper cell cytokine and B cell immunoglobulin production, which is critically dependent on monocytes/macrophages. Our results indicate that previously described increased expression of IL-7 and TLR7 together with increased numbers of macrophages at sites of inflammation in autoimmune diseases like RA and pSS significantly contributes to enhanced lymphocyte activation. PMID:24740301

  1. Plasma-activated medium induced apoptosis on tumor cells

    NASA Astrophysics Data System (ADS)

    Hori, Masaru; Tanaka, Hiromasa; Mizuno, Masaaki; Nakamura, Kae; Kajiyama, Hiroaki; Takeda, Keigo; Ishikawa, Kenji; Kano, Hiroyuki; Kikkawa, Fumitaka

    2013-09-01

    The non-equilibrium atmospheric pressure plasma (NEAPP) has attracted attention in cancer therapy. In this study, the fresh medium was treated with our developed NEAPP, ultra-high electron density (approximately 2 × 1016 cm-3). The medium called the plasma-activated medium (PAM) killed not normal cells but tumor cells through induction of apoptosis. Cell proliferation assays showed that the tumor cells were selectively killed by the PAM. Those cells induced apoptosis using an apoptotic molecular marker, cleaved Caspase3/7. The molecular mechanisms of PAM-mediated apoptosis in the tumor cells were also found that the PAM downregulated the expression of AKT kinase, a marker molecule in a survival signal transduction pathway. These results suggest that PAM may be a promising tool for tumor therapy by downregulating the survival signals in cancers.

  2. Eosinophil resistance to glucocorticoid-induced apoptosis is mediated by the transcription factor NFIL3.

    PubMed

    Pazdrak, Konrad; Moon, Young; Straub, Christof; Stafford, Susan; Kurosky, Alexander

    2016-04-01

    The mainstay of asthma therapy, glucocorticoids (GCs) exert their therapeutic effects through the inhibition of inflammatory signaling and induction of eosinophil apoptosis. However, laboratory and clinical observations of GC-resistant asthma suggest that GCs' effects on eosinophil viability may depend on the state of eosinophil activation. In the present study we demonstrate that eosinophils stimulated with IL-5 show impaired pro-apoptotic response to GCs. We sought to determine the contribution of GC-mediated transactivating (TA) and transrepressing (TR) pathways in modulation of activated eosinophils' response to GC by comparing their response to the selective GC receptor (GR) agonist Compound A (CpdA) devoid of TA activity to that upon treatment with Dexamethasone (Dex). IL-5-activated eosinophils showed contrasting responses to CpdA and Dex, as IL-5-treated eosinophils showed no increase in apoptosis compared to cells treated with Dex alone, while CpdA elicited an apoptotic response regardless of IL-5 stimulation. Proteomic analysis revealed that both Nuclear Factor IL-3 (NFIL3) and Map Kinase Phosphatase 1 (MKP1) were inducible by IL-5 and enhanced by Dex; however, CpdA had no effect on NFIL3 and MKP1 expression. We found that inhibiting NFIL3 with specific siRNA or by blocking the IL-5-inducible Pim-1 kinase abrogated the protective effect of IL-5 on Dex-induced apoptosis, indicating crosstalk between IL-5 anti-apoptotic pathways and GR-mediated TA signaling occurring via the NFIL3 molecule. Collectively, these results indicate that (1) GCs' TA pathway may support eosinophil viability in IL-5-stimulated cells through synergistic upregulation of NFIL3; and (2) functional inhibition of IL-5 signaling (anti-Pim1) or the use of selective GR agonists that don't upregulate NFIL3 may be effective strategies for the restoring pro-apoptotic effect of GCs on IL-5-activated eosinophils. PMID:26880402

  3. A novel mechanism of dasatinib-induced apoptosis in chronic myeloid leukemia; ceramide synthase and ceramide clearance genes.

    PubMed

    Gencer, Emel B; Ural, Ali U; Avcu, Ferit; Baran, Yusuf

    2011-11-01

    Sphingolipids are bioeffector molecules that control various aspects of cell growth, proliferation, apoptosis, and drug resistance. Ceramides, the central molecule of sphingolipid metabolism, are inducer of apoptosis and inhibitors of proliferation. Sphingosine-1-phosphate (S1P) and glucosyleceramide, converted from ceramides by sphingosine kinase-1 (SK-1) and glucosyleceramide synthase (GCS) enzymes, respectively, inhibit apoptosis and develop resistance to chemotherapeutic drugs. In this study, we examined the therapeutic potentials of bioactive sphingolipids in chronic myeloid leukemia (CML) alone and in combination with dasatinib in addition to investigate the roles of ceramide-metabolizing genes in dasatinib-induced apoptosis. Cytotoxic effects of dasatinib, C8:ceramide, PDMP, and SK-1 inhibitor were determined by XTT cell proliferation assay. Changes in caspase-3 enzyme activity and mitochondrial membrane potential (MMP) were measured using caspase-3 colorimetric assay and JC-1 MMP detection kit. Expression levels of ceramide-metabolizing genes were examined by qRT-PCR. Application of ceramide analogs and inhibitors of ceramide clearance genes decreased cell proliferation and induced apoptosis. Targeting bioactive sphingolipids towards generation/accumulation of ceramides increased apoptotic effects of dasatinib, synergistically. It was shown for the first time that dasatinib induces apoptosis through downregulating expression levels of antiapoptotic SK-1 but not GCS, and upregulating expression levels of ceramide synthase (CerS) genes, especially CerS1, in K562 cells. On the other hand, dasatinib downregulates expression levels of both GCS and SK-1 and upregulate apoptotic CerS2, -5 and -6 genes in Meg-01 cells. Increasing endogenous ceramide levels and decreasing prosurvival lipids, S1P, and GC, can open the way of more effective treatment of CML. PMID:21455605

  4. p73-induced apoptosis: A question of compartments and cooperation

    SciTech Connect

    Dobbelstein, Matthias; Strano, Sabrina; Roth, Judith; Blandino, Giovanni . E-mail: blandino@ifo.it

    2005-06-10

    The transcriptionally active forms of p73 are capable of inducing apoptosis, and the isoforms termed TAp73 are important players when E2F and its oncogenic activators induce programmed cell death. However, the conditions under that TAp73 can kill a cell remain to be clarified. Recently, it has been found that p73 proteins are not merely floating in the nucleoplasm but rather can associate with specific compartments in the cell. Examples of intranuclear compartments associated with p73 proteins include the PML oncogenic domains and the nuclear matrix. In addition, p73 is found in the cytoplasm. It remains to be seen whether p73 might also associate with mitochondria, in analogy with p53. The relocalization of p73 is expected to be mediated by specific binding partners, mostly other proteins. Here, we discuss the possibility that the compartmentalization of p73, and the cooperation with the corresponding binding partners, might decide about its apoptosis-inducing activity.

  5. Molecular Mechanisms of Particle Ration Induced Apoptosis in Lymphocyte

    NASA Astrophysics Data System (ADS)

    Shi, Yufang

    Space radiation, composed of high-energy charged nuclei (HZE particles) and protons, has been previously shown to severely impact immune homeostasis in mice. To determine the molecular mechanisms that mediate acute lymphocyte depletion following exposure to HZE particle radiation mice were exposed to particle radiation beams at Brookhaven National Laboratory. We found that mice given whole body 5 6Fe particle irradiation (1GeV /n) had dose-dependent losses in total lymphocyte numbers in the spleen and thymus (using 200, 100 and 50 cGy), with thymocytes being more sensitive than splenocytes. All phenotypic subsets were reduced in number. In general, T cells and B cells were equally sensitive, while CD8+ T cells were more senstive than CD4+ T cells. In the thymus, immature CD4+CD8+ double-positive thymocytes were exquisitely sensitive to radiation-induced losses, single-positive CD4 or CD8 cells were less sensitive, and the least mature double negative cells were resistant. Irradiation of mice deficient in genes encoding essential apoptosis-inducing proteins revealed that the mechanism of lymphocyte depletion is independent of Fas ligand and TRAIL (TNF-ralated apoptosis-inducing ligand), in contrast to γ-radiation-induced lymphocyte losses which require the Fas-FasL pathway. Using inhibitors in vitro, lymphocyte apoptosis induced by HZE particle radiation was found to be caspase dependent, and not involve nitric oxide or oxygen free radicals.

  6. Aluminum and benzo[a]pyrene co-operate to induce neuronal apoptosis in vitro.

    PubMed

    Jinzhu, Yin; Qinli, Zhang; Jin, Yang; Pan, Kang; Jianjun, Huang; Qiao, Niu

    2015-06-01

    Toxic and harmful factors co-exist in the environment; these factors often interact to induce combined toxicity, which is the main focus of toxicological research. Furthermore, a large number of studies have shown that aluminum (Al) and benzo[a]pyrene (BaP) are neurotoxic and target the central nervous system to cause neuronal apoptosis. Because we are exposed to both Al and BaP in the air, water, food, and even medicine, the combined effects of these agents in humans must be examined. The present study examines the ability of Al and BaP co-exposure to intensify neuronal apoptosis. The primary neurons of newborn rats were cultured for 5 days, and cells from the same batch that were growing well were selected and assigned to the blank control group, the solvent control group (DMSO+S9+maltol), BaP groups (10, 40 μmol/L), Al (mal)3 groups (50, 100, 400 μmol/L) and co-exposure groups with different combinations of BaP and Al (mal)3. The cell viabilities indicated that 10 μM BaP or 50 μM Al (mal)3 was mildly toxic, and we selected 10 μM BaP+50 μM Al (mal)3 for subsequent co-exposure experiments. The morphological characteristics of cell apoptosis were much more obvious in the co-exposure group than in the Al-exposed cells or the BaP-exposed cells, as observed with a transmission electron microscope and a fluorescence inverted microscope. The apoptotic rates and caspase-3 activity quantitatively significantly differed between the co-exposure and Al-exposure groups, while the BaP-exposure group did not significantly differ from the control group. These results indicate that Al and BaP co-exposure exert synergistic effects on neuronal cell apoptosis. PMID:25971159

  7. Targeted expression of BikDD combined with metronomic doxorubicin induces synergistic antitumor effect through Bax activation in hepatocellular carcinoma.

    PubMed

    Dai, Huei-Yue; Chen, Hui-Yu; Lai, Wei-Chen; Hung, Mien-Chie; Li, Long-Yuan

    2015-09-15

    Conventional chemotherapy is commonly used to treat advanced non-resectable hepatocellular carcinoma (HCC) but this treatment modality has not demonstrated convincing survival benefit in HCC patients. Our previous studies indicated that targeted expression of therapeutic BikDD driven by a liver cancer-specific α-fetoprotein promoter/enhancer (eAFP) in the VISA backbone (eAFP-VISA-BikDD) significantly and specifically kills HCC cells in multiple orthotopic animal models. To enhance its therapeutic efficacy, we combined eAFP-VISA-BikDD with chemotherapeutic agents and found that eAFP-VISA-BikDD plus doxorubicin (Dox) or 5-fluorouracil (5-FU) demonstrated synergistic cytotoxicity in HCC cells. Specifically, the combination of eAFP-VISA-BikDD plus Dox markedly induced apoptosis via increased Bax mitochondrial translocation and cytoplasmic cytochrome c release. Compared with either agent alone, a low dose of Dox combined with eAFP-VISA-BikDD induced better antitumor effect and prolonged longer survival of mice in two orthotopic liver cancer xenograft models. Our findings provide strong preclinical support for evaluating the combined therapy of eAFP-VISA-BikDD and Dox in a clinical setting as a treatment option for HCC. PMID:26247632

  8. PRIMA-1, a mutant p53 reactivator, induces apoptosis and enhances chemotherapeutic cytotoxicity in pancreatic cancer cell lines.

    PubMed

    Izetti, Patricia; Hautefeuille, Agnes; Abujamra, Ana Lucia; de Farias, Caroline Brunetto; Giacomazzi, Juliana; Alemar, Bárbara; Lenz, Guido; Roesler, Rafael; Schwartsmann, Gilberto; Osvaldt, Alessandro Bersch; Hainaut, Pierre; Ashton-Prolla, Patricia

    2014-10-01

    TP53 mutation is a common event in many cancers, including pancreatic adenocarcinoma, where it occurs in 50-70 % of cases. In an effort to reactivate mutant p53 protein, several new drugs are being developed, including PRIMA-1 and PRIMA-1(Met)/APR-246 (p53 reactivation and induction of massive apoptosis). PRIMA-1 has been shown to induce apoptosis in tumor cells by reactivating p53 mutants, but its effect in pancreatic cancer remains unclear. Here we investigated the effects of PRIMA-1 on cell viability, cell cycle and expression of p53-regulated proteins in PANC-1 and BxPC-3 (mutant TP53), and CAPAN-2 (wild-type TP53) pancreatic cell lines. Treatment with PRIMA-1 selectively induced apoptosis and cell cycle arrest in p53 mutant cells compared to CAPAN-2 cells. The growth suppressive effect of PRIMA-1 was markedly reduced in p53 mutant cell lines transfected with p53 siRNA, supporting the role of mutant p53 in PRIMA-1 induced cell death. Moreover, treatment with the thiol group donor N-acetylcysteine completely blocked PRIMA-1-induced apoptosis and reinforced the hypothesis that thiol modifications are important for PRIMA-1 biological activity. In combination treatments, PRIMA-1 enhanced the anti-tumor activity of several chemotherapic drugs against pancreatic cancer cells and also exhibited a pronounced synergistic effect in association with the Mdm2 inhibitor Nutlin-3. Taken together, our data indicate that PRIMA-1 induces apoptosis in p53 mutant pancreatic cancer cells by promoting the re-activation of p53 and inducing proapoptotic signaling pathways, providing in vitro evidence for a potential therapeutic approach in pancreatic cancer. PMID:24838627

  9. Carfilzomib potentiates CUDC-101-induced apoptosis in anaplastic thyroid cancer

    PubMed Central

    Zhang, Lisa; Boufraqech, Myriem; Lake, Ross; Kebebew, Electron

    2016-01-01

    Anaplastic thyroid cancer (ATC) is one of the most aggressive human malignancies, with no effective treatment currently available. Previously, we identified agents active against ATC cells, both in vitro and in vivo, using quantitative high-throughput screening of 3282 clinically approved drugs and small molecules. Here, we report that combining two of these active agents, carfilzomib, a second-generation proteasome inhibitor, and CUDC-101, a histone deacetylase and multi-kinase inhibitor, results in increased, synergistic activity in ATC cells. The combination of carfilzomib and CUDC-101 synergistically inhibited cellular proliferation and caused cell death in multiple ATC cell lines harboring various driver mutations observed in human ATC tumors. This increased anti-ATC effect was associated with a synergistically enhanced G2/M cell cycle arrest and increased caspase 3/7 activity induced by the drug combination. Mechanistically, treatment with carfilzomib and CUDC-101 increased p21 expression and poly (ADP-ribose) polymerase protein cleavage. Our results suggest that combining carfilzomib and CUDC-101 would offer an effective therapeutic strategy to treat ATC. PMID:26934320

  10. Carfilzomib potentiates CUDC-101-induced apoptosis in anaplastic thyroid cancer.

    PubMed

    Zhang, Lisa; Boufraqech, Myriem; Lake, Ross; Kebebew, Electron

    2016-03-29

    Anaplastic thyroid cancer (ATC) is one of the most aggressive human malignancies, with no effective treatment currently available. Previously, we identified agents active against ATC cells, both in vitro and in vivo, using quantitative high-throughput screening of 3282 clinically approved drugs and small molecules. Here, we report that combining two of these active agents, carfilzomib, a second-generation proteasome inhibitor, and CUDC-101, a histone deacetylase and multi-kinase inhibitor, results in increased, synergistic activity in ATC cells. The combination of carfilzomib and CUDC-101 synergistically inhibited cellular proliferation and caused cell death in multiple ATC cell lines harboring various driver mutations observed in human ATC tumors. This increased anti-ATC effect was associated with a synergistically enhanced G2/M cell cycle arrest and increased caspase 3/7 activity induced by the drug combination. Mechanistically, treatment with carfilzomib and CUDC-101 increased p21 expression and poly (ADP-ribose) polymerase protein cleavage. Our results suggest that combining carfilzomib and CUDC-101 would offer an effective therapeutic strategy to treat ATC. PMID:26934320

  11. Herbal Medicine as Inducers of Apoptosis in Cancer Treatment

    PubMed Central

    Safarzadeh, Elham; Sandoghchian Shotorbani, Siamak; Baradaran, Behzad

    2014-01-01

    Cancer is uncontrolled growth of abnormal cells in the body. Nowadays, cancer is considered as a human tragedy and one of the most prevalent diseases in the wide, and its mortality resulting from cancer is being increased. It seems necessary to identify new strategies to prevent and treat such a deadly disease. Control survival and death of cancerous cell are important strategies in the management and therapy of cancer. Anticancer agents should kill the cancerous cell with the minimal side effect on normal cells that is possible through the induction of apoptosis. Apoptosis is known as programmed cell death in both normal and damaged tissues. This process includes some morphologically changes in cells such as rapid condensation and budding of the cell, formation of membrane-enclosed apoptotic bodies with well-preserved organelles. Induction of apoptosis is one of the most important markers of cytotoxic antitumor agents. Some natural compounds including plants induce apoptotic pathways that are blocked in cancer cells through various mechanisms in cancer cells. Multiple surveys reported that people with cancer commonly use herbs or herbal products. Vinca Alkaloids, Texans, podo phyllotoxin, Camptothecins have been clinically used as Plant derived anticancer agents. The present review summarizes the literature published so far regarding herbal medicine used as inducers of apoptosis in cancer. PMID:25364657

  12. Herbal medicine as inducers of apoptosis in cancer treatment.

    PubMed

    Safarzadeh, Elham; Sandoghchian Shotorbani, Siamak; Baradaran, Behzad

    2014-10-01

    Cancer is uncontrolled growth of abnormal cells in the body. Nowadays, cancer is considered as a human tragedy and one of the most prevalent diseases in the wide, and its mortality resulting from cancer is being increased. It seems necessary to identify new strategies to prevent and treat such a deadly disease. Control survival and death of cancerous cell are important strategies in the management and therapy of cancer. Anticancer agents should kill the cancerous cell with the minimal side effect on normal cells that is possible through the induction of apoptosis. Apoptosis is known as programmed cell death in both normal and damaged tissues. This process includes some morphologically changes in cells such as rapid condensation and budding of the cell, formation of membrane-enclosed apoptotic bodies with well-preserved organelles. Induction of apoptosis is one of the most important markers of cytotoxic antitumor agents. Some natural compounds including plants induce apoptotic pathways that are blocked in cancer cells through various mechanisms in cancer cells. Multiple surveys reported that people with cancer commonly use herbs or herbal products. Vinca Alkaloids, Texans, podo phyllotoxin, Camptothecins have been clinically used as Plant derived anticancer agents. The present review summarizes the literature published so far regarding herbal medicine used as inducers of apoptosis in cancer. PMID:25364657

  13. Infrasound sensitizes human glioblastoma cells to cisplatin-induced apoptosis.

    PubMed

    Rachlin, Kenneth; Moore, Dan H; Yount, Garret

    2013-11-01

    The development of nontoxic agents that can selectively enhance the cytotoxicity of chemotherapy is an important aim in oncology. This study evaluates the ability of infrasound exposure to sensitize glioblastoma cells to cisplatin-induced apoptosis. The infrasound was delivered using a device designed to replicate the unique infrasound emissions measured during external Qigong treatments. Human glioblastoma cell lines harboring wild-type p53 (U87) or mutant p53 (U251, SF210, and SF188) were treated in culture with cisplatin, infrasound emissions, or the combination of the 2 agents. Induction of apoptosis was quantified after 24 hours by flow cytometry following annexin V/propidium iodide staining. Infrasound emissions alone, delivered at moderate levels (~10 mPa) with dynamic frequency content (7-13 Hz), did not induce apoptosis, yet combining infrasound with cisplatin augmented the induction of apoptosis by cisplatin in all the 4 cell lines (P < .05). Increased cellular uptake of the fluorophore calcein associated with infrasound exposure was quantified by fluorescence microscopy as well as flow cytometry, demonstrating increased cell membrane permeability. The 4 cell lines differed in the degree to which infrasound exposure increased calcein uptake, and these differences were predictive of the extent to which infrasound enhanced cisplatin-induced apoptosis. When exposed to specific frequencies, membrane permeabilization also appeared to be differentially responsive for each cell line, suggesting the potential for selective targeting of tissue types using isolated infrasonic frequencies. Additionally, the pressure amplitudes used in this study were several orders of magnitude less than those used in similar studies involving ultrasound and shock waves. The results of this study provide support for using infrasound to enhance the chemotherapeutic effects of cisplatin in a clinical setting. PMID:23165942

  14. Minerval induces apoptosis in Jurkat and other cancer cells

    PubMed Central

    Llado, Victoria; Gutierrez, Antonio; Martínez, Jordi; Casas, Jesús; Terés, Silvia; Higuera, Mónica; Galmés, Antonio; Saus, Carles; Besalduch, Joan; Busquets, Xavier; Escribá, Pablo V

    2010-01-01

    Abstract Minerval is an oleic acid synthetic analogue that impairs lung cancer (A549) cell proliferation upon modulation of the plasma membrane lipid structure and subsequent regulation of protein kinase C localization and activity. However, this mechanism does not fully explain the regression of tumours induced by this drug in animal models of cancer. Here we show that Minerval also induced apoptosis in Jurkat T-lymphoblastic leukaemia and other cancer cells. Minerval inhibited proliferation of Jurkat cells, concomitant with a decrease of cyclin D3 and cdk2 (cyclin-dependent kinase2). In addition, the changes that induced on Jurkat cell membrane organization caused clustering (capping) of the death receptor Fas (CD95), caspase-8 activation and initiation of the extrinsic apoptosis pathway, which finally resulted in programmed cell death. The present results suggest that the intrinsic pathway (associated with caspase-9 function) was activated downstream by caspase-8. In a xenograft model of human leukaemia, Minerval also inhibited tumour progression and induced tumour cell death. Studies carried out in a wide variety of cancer cell types demonstrated that apoptosis was the main molecular mechanism triggered by Minerval. This is the first report on the pro-apoptotic activity of Minerval, and in part explains the effectiveness of this non-toxic anticancer drug and its wide spectrum against different types of cancer. PMID:19413889

  15. Selenite suppression of cadmium-induced testicular apoptosis.

    PubMed

    Jones, M M; Xu, C; Ladd, P A

    1997-01-15

    The characteristic apoptotic ladder-like patterns of rat testicular DNA on agarose gel electrophoresis which results from treatment with CdCl2 are suppressed by the administration of Na2SeO3. The examination of testicular tissue using an ELISA programmed cell death detection procedure confirmed this selenite suppression of cadmium-induced apoptosis. The administration of the Na2SeO3 at either 0.5, 1, 2 h prior to or 0.5, 1, 2 h after the administration of the CdCl2 appear to be almost equally effective at suppressing the apoptotic response. These results are in accord with previous studies on the Na2SeO3 suppression of cadmium induced necrotic changes in tissues and suggest that Na2SeO3 interferes with both necrosis and apoptosis. PMID:9020518

  16. Pulse mode of laser photodynamic treatment induced cell apoptosis.

    PubMed

    Klimenko, Vladimir V; Knyazev, Nickolay A; Moiseenko, Fedor V; Rusanov, Anatoliy A; Bogdanov, Alexey A; Dubina, Michael V

    2016-03-01

    One of the factors limiting photodynamic therapy (PDT) is hypoxia in tumor cells during photodynamic action. PDT with pulse mode irradiation and appropriate irradiation parameters could be more effective in the singlet oxygen generation and tissue re-oxygenation than continuous wave (CW) mode. We theoretically demonstrate differences between the cumulative singlet oxygen concentration in PDT using pulse mode and CW mode of laser irradiation. In vitro experimental results show that photodynamic treatment with pulse mode irradiation has similar cytotoxicity to CW mode and induces mainly cell apoptosis, whereas CW mode induces necrotic cell death. We assume that the cumulative singlet oxygen concentration and the temporal distribution of singlet oxygen are important in photodynamic cytotoxicity and apoptosis initiation. We expect our research may improve irradiation protocols and photodynamic therapy efficiency. PMID:26790610

  17. PX-12 inhibits the growth of hepatocelluar carcinoma by inducing S-phase arrest, ROS-dependent apoptosis and enhances 5-FU cytotoxicity

    PubMed Central

    Li, Guang-Zhen; Liang, Hui-Fang; Liao, Bo; Zhang, Lei; Ni, Ya-An; Zhou, Hong-Hao; Zhang, Er-Lei; Zhang, Bi-Xiang; Chen, Xiao-Ping

    2015-01-01

    Background: 1-methylpropyl 2-imidazolyl disulfide (PX-12), a thioredoxin 1 (Trx1) inhibitor, has been investigated in a number of ancers, but its effectiveness in the treatment of hepatocellular carcinoma (HCC) has not been reported. PX-12 has generated considerable interest in its use in a variety of solid tumors, yet most studies have confined their interests to using PX-12 as a single agent. The aim of this study is to investigate whether PX-12 inhibits cell growth and has a synergistic anti-tumor effect in combination with 5-fluorouracil (5-FU) in HCC. Methods: Cells were treated with different concentrations of PX-12 and 5-FU. Cell viability assays, colony formation assay, cell cycle assay, reactive oxygen species (ROS) assay, apoptosis analysis, western blot assay, immunohistochemistry and xenograft tumorigenicity assay were performed. Results: Treatment with PX-12 inhibited cell growth, induced S-phase arrest, and increased ROS levels. PX-12-induced apoptosis and inhibition of colony formation were associated with the generation of ROS, and inhibition of ROS attenuated PX-12-induced apoptosis and inhibition of colony formation. Treatment with PX-12 increased the expression of bax and reduced the expression of bcl-2, indicating that PX-12-mediated apoptosis is mitochondria-dependent. PX-12 also exerted a synergistic effect with 5-FU tosignificantly suppress tumorigenicity both in vitro and in vivo. Inhibition of ROS accumulation reduced the synergistic effect of PX-12 and 5-FU. Conclusions: PX-12 has anti-tumor activity and a synergistic effect in combination with 5-FU in HCC. Treatment with PX-12 alone or in combination with 5-FU may have clinical use in the treatment of HCC and other cancers. PMID:26550453

  18. [Apoptosis-inducing effect of valproic acid combined with arsenic trioxide on RPMI 8226 cells and its mechanism].

    PubMed

    Wang, Xiao-Ning; Zhang, Mei

    2014-08-01

    This study was aimed to investigate the apoptosis-inducing effect of valproic acid (VPA) combined with arsenic trioxide (ATO) on human multiple myeloma RPMI 8226 cells and its mechanism. The cell proliferation of RPMI 8226 cells was assayed by CCK-8 method. The cell apoptosis were detected by flow cytometry. Semiquantitative RT-PCR and Western blot were applied respectively to detect the mRNA and protein expression level of BCL-2, BAX, caspase-8 and caspase-9 gene. The results showed that both the VPA and ATO inhibited RPMI 8226 cell proliferation. The combination of ATO and VPA has synergistic effect (Q values greater than 1.15). The RPMI 8226 cell apoptosis rate in combined drug group was significantly higher than that in single drug group (P < 0.05). The mRNA and protein expressions of BCL-2 gene in combined drug group decreased, while the mRNA and protein expressions of BAX, caspase-8 and caspase-9 significantly increased, compared with single drug group (P < 0.05) . It is concluded that VPA can enhance the sensitivity of RPMI 8226 cells to ATO-induced apoptosis, which may be associated with decreasing the BCL-2 expression and increasing the BAX, caspase-8 and caspase-9 gene expression. PMID:25130820

  19. Alpha particles induce apoptosis through the sphingomyelin pathway.

    PubMed

    Seideman, Jonathan H; Stancevic, Branka; Rotolo, Jimmy A; McDevitt, Michael R; Howell, Roger W; Kolesnick, Richard N; Scheinberg, David A

    2011-10-01

    The sphingomyelin pathway involves the enzymatic cleavage of sphingomyelin to produce ceramide, a second messenger that serves as a key mediator in the rapid apoptotic response to various cell stressors. Low-linear energy transfer (LET) γ radiation can initiate this pathway, independent of DNA damage, via the cell membrane. Whether short-ranged, high-LET α particles, which are of interest as potent environmental carcinogens, radiotherapies and potential components of dirty bombs, can act through this mechanism to signal apoptosis is unknown. Here we show that irradiation of Jurkat cells with α particles emitted by the ²²⁵Ac-DOTA-anti-CD3 IgG antibody construct results in dose-dependent apoptosis. This apoptosis was significantly reduced by pretreating cells with cholesterol-depleting nystatin, a reagent known to inhibit ceramide signaling by interfering with membrane raft coalescence and ceramide-rich platform generation. The effects of nystatin on α-particle-induced apoptosis were related to disruption of the ceramide pathway and not to microdosimetry alterations, because similar results were obtained after external irradiation of the cells with a broad beam of collimated α particles using a planar ²⁴¹Am source. External irradiation allowed for more precise control of the dosimetry and geometry of the irradiation, independent of antibody binding or cell internalization kinetics. Mechanistically consistent with these findings, Jurkat cells rapidly increased membrane concentrations of ceramide after external irradiation with an average of five α-particle traversals per cell. These data indicate that α particles can activate the sphingomyelin pathway to induce apoptosis. PMID:21631289

  20. Alpha Particles Induce Apoptosis through the Sphingomyelin Pathway

    PubMed Central

    Seideman, Jonathan H.; Stancevic, Branka; Rotolo, Jimmy A.; McDevitt, Michael R.; Howell, Roger W.; Kolesnick, Richard N.; Scheinberg, David A.

    2011-01-01

    The sphingomyelin pathway involves the enzymatic cleavage of sphingomyelin to produce ceramide, a second messenger that serves as a key mediator in the rapid apoptotic response to various cell stressors. Low-linear energy transfer (LET) γ radiation can initiate this pathway, independent of DNA damage, via the cell membrane. Whether short-ranged, high-LET a particles, which are of interest as potent environmental carcinogens, radiotherapies and potential components of dirty bombs, can act through this mechanism to signal apoptosis is unknown. Here we show that irradiation of Jurkat cells with a particles emitted by the 225Ac-DOTA-anti-CD3 IgG antibody construct results in dose-dependent apoptosis. This apoptosis was significantly reduced by pretreating cells with cholesterol-depleting nystatin, a reagent known to inhibit ceramide signaling by interfering with membrane raft coalescence and ceramide-rich platform generation. The effects of nystatin on α-particle-induced apoptosis were related to disruption of the ceramide pathway and not to microdosimetry alterations, because similar results were obtained after external irradiation of the cells with a broad beam of collimated a particles using a planar 241Am source. External irradiation allowed for more precise control of the dosimetry and geometry of the irradiation, independent of antibody binding or cell internalization kinetics. Mechanistically consistent with these findings, Jurkat cells rapidly increased membrane concentrations of ceramide after external irradiation with an average of five α-particle traversals per cell. These data indicate that a particles can activate the sphingomyelin pathway to induce apoptosis. PMID:21631289

  1. ABT-263 induces apoptosis and synergizes with chemotherapy by targeting stemness pathways in esophageal cancer.

    PubMed

    Chen, Qiongrong; Song, Shumei; Wei, Shaozhong; Liu, Bin; Honjo, Soichiro; Scott, Ailing; Jin, Jiankang; Ma, Lang; Zhu, Haitao; Skinner, Heath D; Johnson, Randy L; Ajani, Jaffer A

    2015-09-22

    Activation of cancer stem cell signaling is central to acquired resistance to therapy in esophageal cancer (EC). ABT-263, a potent Bcl-2 family inhibitor, is active against many tumor types. However, effect of ABT-263 on EC cells and their resistant counterparts are unknown. Here we report that ABT-263 inhibited cell proliferation and induced apoptosis in human EC cells and their chemo-resistant counterparts. The combination of ABT-263 with 5-FU had synergistic lethal effects and amplified apoptosis that does not depend fully on its inhibition of BCL-2 family proteins in EC cells. To further explore the novel mechanisms of ABT-263, proteomic array (RPPAs) were performed and gene set enriched analysis demonstrated that ABT-263 suppresses the expression of many oncogenes including genes that govern stemness pathways. Immunoblotting and immunofluorescence further confirmed reduction in protein expression and transcription in Wnt/β-catenin and YAP/SOX9 axes. Furthermore, ABT263 strongly suppresses cancer stem cell properties in EC cells and the combination of ABT-263 and 5-FU significantly reduced tumor growth in vivo and suppresses the expression of stemness genes. Thus, our findings demonstrated a novel mechanism of ABT-263 antitumor effect in EC and indicating that combination of ABT-263 with cytotoxic drugs is worthy of pursuit in patients with EC. PMID:26317542

  2. Pyoluteorin derivatives induce Mcl-1 degradation and apoptosis in hematological cancer cells

    PubMed Central

    Doi, Kenichiro; Gowda, Krishne; Liu, Qiang; Lin, Jyh-Ming; Sung, Shen-Shu; Dower, Christopher; Claxton, David; Loughran, Thomas P; Amin, Shantu; Wang, Hong-Gang

    2014-01-01

    Mcl-1, a pro-survival member of the Bcl-2 protein family, is an attractive target for cancer therapy. We have recently identified the natural product marinopyrrole A (maritoclax) as a novel small molecule Mcl-1 inhibitor. Here, we describe the structure-activity relationship study of pyoluteorin derivatives based on maritoclax. To date, we synthesized over 30 derivatives of maritoclax and evaluated their inhibitory actions and cytotoxicity toward Mcl-1-dependent cell lines. As a result, several functional groups were identified in the pyoluteorin motif that significantly potentiate biological activity. A number of such derivatives, KS04 and KS18, interacted with Mcl-1 in a conserved fashion according to NMR spectroscopy and molecular modeling. KS04 and KS18 induced apoptosis selectively in Mcl-1-dependent but not Bcl-2-dependent K562 cells through selective Mcl-1 down-regulation, and synergistically enhanced apoptosis in combination with ABT-737. Moreover, the intraperitoneal administration of KS18 (10 mg/kg/d) and ABT-737 (20 mg/kg/d) significantly suppressed the growth of ABT-737-resistant HL-60 xenografts in nude mice without apparent toxicity. Overall, we identified the pharmacophore of pyoluteorin derivatives that act as potent and promising Mcl-1 antagonists against Mcl-1-dependent hematological cancers. PMID:25535900

  3. CHEMOSENSITIZATION BY A NON-APOPTOGENIC HEAT SHOCK PROTEIN 70-BINDING APOPTOSIS INDUCING FACTOR MUTANT

    EPA Science Inventory

    Chemosensitization by a non-apoptogenic heat shock protein 70-binding apoptosis inducing factor mutant

    Abstract
    HSP70 inhibits apoptosis by neutralizing the caspase activator Apaf-1 and by interacting with apoptosis inducing factor (AIF), a mitochondrial flavoprotein wh...

  4. Smac mimetic primes apoptosis-resistant acute myeloid leukaemia cells for cytarabine-induced cell death by triggering necroptosis.

    PubMed

    Chromik, Joerg; Safferthal, Charlotta; Serve, Hubert; Fulda, Simone

    2014-03-01

    The prognosis for patients with acute myeloid leukaemia (AML) is still poor, thus calling for novel treatment strategies. Here, we report that the small-molecule Smac mimetic BV6, which antagonizes Inhibitor of Apoptosis (IAP) proteins, acts in concert with cytarabine (AraC) to trigger cell death in AML cells in a highly synergistic manner (combination index 0.02-0.27). Similarly, BV6 cooperates with AraC to trigger cell death in primary AML samples, underscoring the clinical relevance of our findings. Molecular studies reveal that the TNFα-blocking antibody Enbrel significantly reduces BV6/AraC-induced cell death, demonstrating that an autocrine/paracrine TNFα loop mediates cell death. Furthermore, BV6 and AraC synergize to induce loss of mitochondrial membrane potential, caspase activation and DNA fragmentation, consistent with apoptotic cell death. Nevertheless, the caspase inhibitor zVAD.fmk fails to protect against BV6/AraC-induced cell death. Intriguingly, this cell death upon caspase inhibition is significantly reduced by pharmacological inhibition of two key components of necroptosis signaling, i.e. by RIP1 kinase inhibitor Necrostatin-1 or MLKL inhibitor NSA. Thus, BV6 sensitizes AML cells to AraC-induced cell death and overcomes apoptosis resistance by triggering necroptosis as alternative form of cell death. These findings have important implications for Smac mimetic-based strategies to bypass apoptosis resistance of AML. PMID:24184825

  5. Oxidative Stress Mediates Radiation Lung Injury by Inducing Apoptosis

    SciTech Connect

    Zhang Yu; Zhang Xiuwu; Rabbani, Zahid N.; Jackson, Isabel L.; Vujaskovic, Zeljko

    2012-06-01

    Purpose: Apoptosis in irradiated normal lung tissue has been observed several weeks after radiation. However, the signaling pathway propagating cell death after radiation remains unknown. Methods and Materials: C57BL/6J mice were irradiated with 15 Gy to the whole thorax. Pro-apoptotic signaling was evaluated 6 weeks after radiation with or without administration of AEOL10150, a potent catalytic scavenger of reactive oxygen and nitrogen species. Results: Apoptosis was observed primarily in type I and type II pneumocytes and endothelium. Apoptosis correlated with increased PTEN expression, inhibition of downstream PI3K/AKT signaling, and increased p53 and Bax protein levels. Transforming growth factor-{beta}1, Nox4, and oxidative stress were also increased 6 weeks after radiation. Therapeutic administration of AEOL10150 suppressed pro-apoptotic signaling and dramatically reduced the number of apoptotic cells. Conclusion: Increased PTEN signaling after radiation results in apoptosis of lung parenchymal cells. We hypothesize that upregulation of PTEN is influenced by Nox4-derived oxidative stress. To our knowledge, this is the first study to highlight the role of PTEN in radiation-induced pulmonary toxicity.

  6. Synergistic Effects Induced by Combined Treatments of Aqueous Extract of Propolis and Venom

    PubMed Central

    DRIGLA, FLAVIU; BALACESCU, OVIDIU; VISAN, SIMONA; BISBOACA, SIMONA ELENA; BERINDAN-NEAGOE, IOANA; MARGHITAS, LIVIU ALEXANDRU

    2016-01-01

    Background and aims Breast cancer is a heterogeneous disease and the leading cause of cancer mortality worldwide. Triple negative breast cancer (TNBC) is considered to be one of the most aggressive breast neoplasia due to failure of chemotherapy response. Thus, there is an urgent need of finding alternative therapies for TNBC. This study was designed to evaluate the synergistic effect induced by propolis and bee venom on luminal (MCF-7) and TNBC (Hs578T) cell lines. Methods In order to evaluate the synergistic effect of aqueous extract of propolis and bee venom, we treated in combination two breast cancer cell lines: MCF-7(luminal subtype) and Hs578T (TNBC subtype). Results Our results indicate that both cell lines exhibited similar sensitivity to the aqueous extract of propolis at a dilution of 0.072–0.09 mg/ml. The results concerning IC50 for bee venom on MCF-7 cells was 1 mg/ml, 20 times higher than 0.05 mg/ml in Hs578T cells. By combining the aqueous extract of propolis with bee venom, we obtained synergistic effects at a higher concentration, which was 5 and 2 times stronger than the two treatments alone. Conclusion Overall, the results from our study indicated that the combination of aqueous extract of propolis and bee venom treatments induced synergistic antiproliferative effects in a concentration-dependent manner in breast cancer cells. Thus we can hypothesize that the combination of honeybee propolis and venom might be involved in signaling pathways that could overcome cells resistance to therapy. PMID:27004032

  7. Dracorhodin perchlorate induces the apoptosis of glioma cells.

    PubMed

    Chen, Xin; Luo, Junjie; Meng, Linghu; Pan, Taifeng; Zhao, Binjie; Tang, Zhen-Gang; Dai, Yongjian

    2016-04-01

    Dracorhodin perchlorate (Dp), a synthetic analogue of the antimicrobial anthocyanin red pigment, has recently been shown to induce apoptotic cell death in various types of cancer cells. Yet, the inhibitory effect of Dp on human glioma cells remains uninvestigated. Therefore, in the present study, 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay and flow cytometry were used to detect cell viability and cell cycle progression in glioma U87MG and T98G cells, respectively. Annexin V-FITC/propidium iodide double staining and JC-1 staining were separately applied to determine cellular apoptosis and mitochondrial membrane potential damage in the cells. The expression levels of associated proteins involved in cell cycle progression and apoptosis were measured by western blotting. The activities of caspase‑9/-3 were determined by Caspase-Glo-9/3 assay. The results indicated that Dp treatment significantly inhibited cell proliferation in a dose- and time-dependent manner, and blocked cell cycle progression at the G1/S phase in the U87MG and T98G cells via the upregulation of p53 and p21 protein expression, and simultaneous downregulation of Cdc25A, Cdc2 and P-Cdc2 protein expression. Additionally, Dp treatment led to the loss of cellular mitochondrial membrane potential, and the release of cytochrome c, and strongly induced the occurence of apoptosis. Increased expression levels of Bim and Bax protein and the downregulated expression of Bcl-2 protein were observed. Caspase-9/-3 were activated and their activities were elevated after Dp treatment. These findings indicate that Dp inhibits cell proliferation, induces cell cycle arrest and apoptosis in glioma cells, and is a possible candidate for glioma treatment. PMID:26846469

  8. Inhibitor of Apoptosis Proteins Physically Interact with and Block Apoptosis Induced by Drosophila Proteins HID and GRIM

    PubMed Central

    Vucic, Domagoj; Kaiser, William J.; Miller, Lois K.

    1998-01-01

    Reaper (RPR), HID, and GRIM activate apoptosis in cells programmed to die during Drosophila development. We have previously shown that transient overexpression of RPR in the lepidopteran SF-21 cell line induces apoptosis and that members of the inhibitor of apoptosis (IAP) family of antiapoptotic proteins can inhibit RPR-induced apoptosis and physically interact with RPR through their BIR motifs (D. Vucic, W. J. Kaiser, A. J. Harvey, and L. K. Miller, Proc. Natl. Acad. Sci. USA 94:10183–10188, 1997). In this study, we found that transient overexpression of HID and GRIM also induced apoptosis in the SF-21 cell line. Baculovirus and Drosophila IAPs blocked HID- and GRIM-induced apoptosis and also physically interacted with them through the BIR motifs of the IAPs. The region of sequence similarity shared by RPR, HID, and GRIM, the N-terminal 14 amino acids of each protein, was required for the induction of apoptosis by HID and its binding to IAPs. When stably overexpressed by fusion to an unrelated, nonapoptotic polypeptide, the N-terminal 37 amino acids of HID and GRIM were sufficient to induce apoptosis and confer IAP binding activity. However, GRIM was more complex than HID since the C-terminal 124 amino acids of GRIM retained apoptosis-inducing and IAP binding activity, suggesting the presence of two independent apoptotic motifs within GRIM. Coexpression of IAPs with HID stabilized HID levels and resulted in the accumulation of HID in punctate perinuclear locations which coincided with IAP localization. The physical interaction of IAPs with RPR, HID, and GRIM provides a common molecular mechanism for IAP inhibition of these Drosophila proapoptotic proteins. PMID:9584170

  9. A smart, phase transitional and injectable DOX/PLGA-Fe implant for magnetic-hyperthermia-induced synergistic tumor eradication.

    PubMed

    Gao, Wei; Zheng, Yuanyi; Wang, Ronghui; Chen, Hangrong; Cai, Xiaojun; Lu, Guangming; Chu, Lei; Xu, Chunyan; Zhang, Nan; Wang, Zhigang; Ran, Haitao; Li, Pan; Yang, Chunjiang; Mei, Zhechuan; Song, Jinlin

    2016-01-01

    Magnetic hyperthermia ablation is a new and minimally invasive modality for localized tumor removal. However, an inadequate ablation dosage can leave a residual tumor or cause a variety of complications. In addition, commonly used magnetic nanoparticles can easily escape from the tumor tissue, which present potential safety problems. In this study, a smart phase transitional and injectable implant based on biocompatible poly lactic-co-glycolic acid (PLGA) implant incorporating magnetic material (Fe powder) and anti-cancer drug (doxorubicin (DOX)) was developed. The magnetic-induced hyperthermia and release efficiency of DOX were evaluated in vitro. Drug release can be controlled under external alternating current magnetic field (AMF). The results of the in vivo tumor therapeutic efficacy showed that when exposed to external AMF, this smart injectable DOX/PLGA-Fe implant could converse magnetic energy into heat and accelerate the release of DOX, which leads to increasing the temperature to achieve tumor coagulative necrosis and accelerating the release of DOX to enhance residual tumor apoptosis. Furthermore, there was no leakage of magnetic material, as demonstrated using real-time ultrasound (US) and computerized tomography (CT) imaging, realizing the guidance and monitoring of tumor therapy. In conclusion, this smart phase transitional and injectable implant DOX/PLGA-Fe has the ability to improve the efficiency of this newly developed minimally invasive magnetic ablation of tumor treatment technique, and will provide a new avenue of developing minimally invasive synergistic tumor therapy. PMID:26432438

  10. Select forms of tumor cell apoptosis induce dendritic cell maturation.

    PubMed

    Demaria, Sandra; Santori, Fabio R; Ng, Bruce; Liebes, Leonard; Formenti, Silvia C; Vukmanovic, Stanislav

    2005-03-01

    Dendritic cells (DC) play a crucial role in initiating immune responses to tumors. DC can efficiently present antigens from apoptotic tumor cells, but apoptotic cells are thought to lack the inflammatory signals required to induce DC maturation. Here, we show that apoptosis of 67NR mouse carcinoma cells via the Fas (CD95) pathway or induced by the anticancer drug bortezomib (PS-341) but not by ultraviolet irradiation is associated with the production of maturation signals for DC. These data have important implications for the effects of chemotherapy on antitumor immunity in solid and hematologic malignancies. PMID:15569694

  11. Inhibition of TLR8 mediated signaling promotes BCG induced apoptosis in THP-1 cells.

    PubMed

    Tang, Jun; Zhan, Lingjun; Qin, Chuan

    2016-04-01

    Apoptosis was considered as one of the important host defense mechanisms against mycobacteria infection. In macrophage, the main target cell of Mycobacterium tuberculosis, apoptosis after infection could help kill the bacillus inside and process the antigens for further presentation and proper immune response. Here, we identified a role of TLR8 during the apoptosis induced by Bacillus Calmette Guérin (BCG) infection in THP-1 cells. Knockdown TLR8 further increased the apoptosis induced by BCG infection, and this enhanced apoptosis was caspase-dependent. During this process, Erk1/2, JNK and NFκB pathways were negatively affected and contributed to the enhanced apoptosis. PMID:26657720

  12. Hypoxia-induced resistance to cisplatin-mediated apoptosis in osteosarcoma cells is reversed by gambogic acid independently of HIF-1α.

    PubMed

    Zhao, Wei; Xia, Shi-Qi; Zhuang, Jin-Peng; Zhang, Zhi-Peng; You, Chang-Cheng; Yan, Jing-Long; Xu, Gong-Ping

    2016-09-01

    In vitro evidence of hypoxia-induced resistance to cisplatin (CDDP)-mediated apoptosis exists in human osteosarcoma (OS). Gambogic acid (GA) is a promising chemotherapeutic compound that could increase the chemotherapeutic effectiveness of CDDP in human OS cells by inducing cell cycle arrest and promoting apoptosis. This study examined whether GA could overcome OS cell resistance to CDDP. Hypoxia significantly reduced levels of CDDP-induced apoptosis in the OS cell lines MG63 and HOS. However, combined treatment with GA and CDDP revealed a strong synergistic action between these drugs, and higher protein levels of the apoptosis-related factor Fas, cleaved caspase-8 and cleaved caspase-3 and lower expression of hypoxia-inducible factor (HIF)-1α are detected in both cell lines. Meanwhile, drug resistance was not reversed by exposure to the HIF-1α inhibitor 2-methoxyestradiol. These findings strongly suggest that hypoxia-induced resistance to CDDP is reversed by GA in OS cells independently of HIF-1α. Furthermore, in vivo studies using xenograft mouse models revealed that combination therapy with CDDP and GA exerted increased antitumor effects by inducing apoptosis. Taken together, our results demonstrate that GA may be a new potent therapeutic agent useful for targeting human OS cells. PMID:27473145

  13. Raman spectrum reveals the cell cycle arrest of Triptolide-induced leukemic T-lymphocytes apoptosis

    NASA Astrophysics Data System (ADS)

    Zhang, Daosen; Feng, Yanyan; Zhang, Qinnan; Su, Xin; Lu, Xiaoxu; Liu, Shengde; Zhong, Liyun

    2015-04-01

    Triptolide (TPL), a traditional Chinese medicine extract, possesses anti-inflammatory and anti-tumor properties. Though some research results have implicated that Triptolide (TPL) can be utilized in the treatment of leukemia, it remains controversial about the mechanism of TPL-induced leukemic T-lymphocytes apoptosis. In this study, combining Raman spectroscopic data, principal component analysis (PCA) and atomic force microscopy (AFM) imaging, both the biochemical changes and morphological changes during TPL-induced cell apoptosis were presented. In contrast, the corresponding data during Daunorubicin (DNR)-induced cell apoptosis was also exhibited. The obtained results showed that Raman spectral changes during TPL-induced cell apoptosis were greatly different from DNR-induced cell apoptosis in the early stage of apoptosis but revealed the high similarity in the late stage of apoptosis. Moreover, above Raman spectral changes were respectively consistent with the morphological changes of different stages during TPL-induced apoptosis or DNR-induced apoptosis, including membrane shrinkage and blebbing, chromatin condensation and the formation of apoptotic bodies. Importantly, it was found that Raman spectral changes with TPL-induced apoptosis or DNR-induced apoptosis were respectively related with the cell cycle G1 phase arrest or G1 and S phase arrest.

  14. Erythropoietin protects cardiac myocytes against anthracycline-induced apoptosis

    SciTech Connect

    Fu Ping; Arcasoy, Murat O. . E-mail: arcas001@mc.duke.edu

    2007-03-09

    The cardiotoxic adverse effects of anthracycline antibiotics limit their therapeutic utility as essential components of chemotherapy regimens for hematologic and solid malignancies. Here we show that the hematopoietic cytokine erythropoietin attenuates doxorubicin-induced apoptosis of primary neonatal rat ventricular cardiomyocytes in a dose-dependent manner. Erythropoietin treatment induced rapid, time-dependent phosphorylation of MAP kinases (MAPK) Erk1/2 and the phosphatidylinositol 3-kinase substrate Akt. Treatment of cardiomyocytes with inhibitors of phosphatidylinositol 3-kinase (LY294002) or Akt (Akti-1/2) abolished the protective effect of erythropoietin, whereas treatment with MAPK kinase (MEK1) inhibitor U0126 did not. Erythropoietin also induced the phosphorylation of GSK-3{beta}, a downstream target of PI3K-Akt. Because phosphorylation is known to inactivate GSK-3{beta}, we investigated whether GSK-3{beta} inhibition is cardioprotective. We found that GSK-3{beta} inhibitors SB216763 or lithium chloride blocked doxorubicin-induced cardiomyocyte apoptosis in a manner similar to erythropoietin, suggesting that GSK-3{beta} inhibition is involved in erythropoietin-mediated cardioprotection. Erythropoietin may serve as a novel cardioprotective agent against anthracycline-induced cardiotoxicity.

  15. Tamoxifen Induces Apoptosis of Leishmania major Promastigotes in Vitro

    PubMed Central

    Doroodgar, Masoud; Delavari, Mahdi; Doroodgar, Moein; Abbasi, Ali; Taherian, Ali Akbar; Doroodgar, Abbas

    2016-01-01

    Tamoxifen is an antagonist of the estrogen receptor and currently used for the treatment of breast cancer. The current treatment of cutaneous leishmaniasis with pentavalent antimony compounds is not satisfactory. Therefore, in this study, due to its antileishmanial activity, effects of tamoxifen on the growth of promastigotes and amastigotes of Leishmania major Iranian strain were evaluated in vitro. Promastigotes and amastigotes were treated with different concentrations (1, 5, 10, 20, and 50 μg/ml) and time periods (24, 48, and 72 hr) of tamoxifen. After tamoxifen treatment, MTT assay (3-[4,5-dimethylthiazol-2-yl]-2,5 biphenyl tetrazolium bromide assay) was used to determine the percentage of live parasites and Graph Pad Prism software to calculate IC50. Flow cytometry was applied to investigate the induction of tamoxifen-induced apoptosis in promastigotes. The half maximal inhibitory concentration (IC50) of tamoxifen on promastigotes was 2.6 μg/ml after 24 hr treatment. Flow cytometry analysis showed that tamoxifen induced early and late apoptosis in Leishmania promastigotes. While after 48 hr in control group the apoptosis was 2.0%, the 50 µg/L concentration of tamoxifen increased it to 59.7%. Based on the in vitro antileishmanial effect, tamoxifen might be used for leishmaniasis treatment; however, further researches on in vivo effects of tamoxifen in animal models are needed. PMID:26951973

  16. Histone deacetylase inhibitors and aspirin interact synergistically to induce cell death in ovarian cancer cells.

    PubMed

    Sonnemann, Jürgen; Hüls, Isabel; Sigler, Michael; Palani, Chithra D; Hong, Le Thi Thu; Völker, Uwe; Kroemer, Heyo K; Beck, James F

    2008-07-01

    Histone deacetylase inhibitors (HDIs) as well as non-steroidal anti-inflammatory drugs including aspirin show promise as antineoplastic agents. The treatment with both HDIs and aspirin can result in hyperacetylation of proteins. In this study, we investigated whether HDIs and aspirin interacted in inducing anticancer activity and histone acetylation. We found that the HDIs, suberoylanilide hydroxamic acid and sodium butyrate, and aspirin cooperated to induce cell death in the ovarian cancer cell line, A2780. The effect was synergistic, as evidenced by CI-isobologram analysis. However, aspirin had no effect on histone acetylation, neither in the absence nor presence of HDIs. To gain insight into the mechanism underlying the synergistic action of HDIs and aspirin, we employed the deacetylated metabolite of aspirin, salicylic acid, and the cyclooxygenase-1- and -2-selective inhibitors, SC-560 and NS-398, respectively. We found that HDIs and salicylic acid interacted synergistically, albeit less efficiently than HDIs and aspirin, to induce cancer cell death, suggesting that the acetyl and the salicyl moiety contributed to the cooperative interaction of aspirin with HDIs. SC-560 and NS-398 had little effect both when applied alone or in conjunction with HDIs, indicating that the combinatorial effect of HDIs and aspirin was not the result of cyclo-oxygenase inhibition. In conclusion, our study demonstrates that HDIs and aspirin synergize to induce cancer cell death and, thus, provides a rationale for a more in-depth exploration into the potential of combining HDIs and aspirin as a strategy for anticancer therapy. PMID:18575740

  17. Apigenin enhances the cytotoxic effects of tumor necrosis factor-related apoptosis-inducing ligand in human rheumatoid arthritis fibroblast-like synoviocytes.

    PubMed

    Sun, Qing-Wen; Jiang, Song-Min; Yang, Ke; Zheng, Jian-Ming; Zhang, Li; Xu, Wei-Dong

    2012-05-01

    Activated rheumatoid arthritis (RA) fibroblast-like synoviocytes (RAFLSs) play a central role in both initiating and driving RA. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has been documented to induce apoptosis only in a small proportion of RAFLSs, which is followed by an induction of proliferation in surviving cells. Apigenin, a chemopreventive bioflavonoid, exhibits proapoptotic activity in many types of cells. In the present study, we sought to determine whether apigenin could enhance the cytotoxic effect of TRAIL on activated RAFLSs. Human RAFLSs isolated from patients with RA were treated with TRAIL (1 nM), apigenin (20 μM), or their combination, and subjected to apoptosis analysis after a 24-h incubation and proliferation analysis after a 72-h incubation. Apoptosis assay revealed that TRAIL or apigenin alone induced a marked apoptosis in RAFLS and their combination yielded a synergistic increase in RAFLS apoptosis. Immunoblotting analysis of apoptosis regulators demonstrated that combined treatment with apigenin increased caspase-3 expression and activity and decreased the Bcl-2/Bax ratio relative to treatment with TRAIL alone. The presence of apigenin significantly restrained TRAIL-induced RAFLS proliferation, coupled with restoration of the expression of two cell-cycle inhibitors p21 and p27. Moreover, the combination with apigenin blunted TRAIL-induced activation of the phosphatidylinositol 3-kinase (PI3-K)/Akt pathway. Our data collectively demonstrate that apigenin sensitizes RAFLS to TRAIL-induced apoptosis and counteracts TRAIL-dependent RAFLS proliferation, which is likely mediated through inactivation of PI3-K/Akt signaling pathway. PMID:22189539

  18. Apoptosis induced by granzyme B-glycosaminoglycan complexes: implications for granule-mediated apoptosis in vivo.

    PubMed

    Galvin, J P; Spaeny-Dekking, L H; Wang, B; Seth, P; Hack, C E; Froelich, C J

    1999-05-01

    Lymphocyte granule-mediated apoptosis occurs by perforin-mediated intracellular delivery of granule-associated serine proteases (granzymes). A granule-associated proteoglycan, namely serglycin, that contains chondroitin 4-sulfate (CS) glycosaminoglycans is present in the granules of cytotoxic cells. Serglycin acts as scaffold for packaging the positively charged granzymes and probably chaperones the proteases secreted extracellularly. To learn how the interaction of granzyme B (GrB) with serglycin might influence the apoptotic potential of this proteases, we have evaluated a model system where desalted CS is combined with isolated human granzyme. CS-GrB complexes were very stable, remaining undissociated in salt concentrations upwards to 500 mM (pH 7.4). On the basis of a capture enzyme immunoassay that accurately detects GrB, equivalent amounts of active free and CS-GrB, delivered by perforin or adenovirus, efficiently induced apoptosis in Jurkat cells and produced a similar time-dependent increase in caspase-3-like activity. CS-GrB processed isolated caspases-3 and -7 less efficiently than free granzyme. However, when added to cytosolic extracts, rates of processing were nearly equivalent for the two forms, suggesting cationic GrB may nonspecifically bind cytosolic proteins, leading to reduce proteolytic activity. Finally, GrB was found to be exocytosed from lymphocyte-activated killer cells as a neutral, high macromolecular weight complex, which possessed apoptotic activity. Collectively, the results indicate that neutral, high m.w. GrB has the capacity to induce cell death and will be useful to study the mechanism of cytotoxic cell-mediated apoptosis in vitro. PMID:10228010

  19. Roscovitine ameliorates endotoxin-induced uveitis through neutrophil apoptosis.

    PubMed

    Jiang, Zhao-Xin; Qiu, Suo; Lou, Bing-Sheng; Yang, Yao; Wang, Wen-Cong; Lin, Xiao-Feng

    2016-08-01

    Neutrophils have been recognized as critical response cells during the pathogenesis of endotoxin‑induced uveitis (EIU). Apoptosis of neutrophils induced by roscovitine has previously been demonstrated to ameliorate inflammation in several in vivo models. The present study aimed to assess whether roscovitine ameliorates EIU. EIU was induced in female C57BL/6 mice by a single intravitreal injection of lipopolysaccharide (LPS; 250 ng). The mice were divided into three groups as follows: LPS alone, LPS plus vehicle, LPS plus roscovitine (50 mg/kg). The mice were euthanized 12, 24, 48 and 72 h after LPS‑induced uveitis. Accumulation of inflammatory cells in the vitreous body was confirmed by immunohistochemistry, and quantified following hematoxylin and eosin staining. Terminal deoxynucleotidyl transferase dUTP nick‑end labeling was performed to detect of apoptotic cells. The mRNA levels of inflammatory cytokines were analyzed by reverse transcription‑quantitative polymerase chain reaction and the changes in protein levels were analyzed by western blotting. Inflammatory cells accumulated in the vitreous near the optic nerve head and the quantity peaked at 24 h after LPS injection. Immunohistochemistry revealed that the majority of the inflammatory cells were neutrophils. The number of infiltrating cells was similar in the LPS and LPS plus vehicle groups, while there were significantly less in the roscovitine group at 24 h. Apoptosis of neutrophils was observed between 12 and 48 h after roscovitine injection, while no apoptosis was observed in the other groups. The mRNA expression levels of GMCSF, CINC‑1 and ICAM‑1 peaked at 12 h after LPS injection, and decreased to normal levels at 72 h. This trend in mRNA expression was similar in the LPS and LPS plus vehicle groups; however, the expression levels decreased more quickly in the roscovitine group at 24 and 48 h. Following roscovitine administration, upregulated cleaved caspase 3 expression levels

  20. Roscovitine ameliorates endotoxin-induced uveitis through neutrophil apoptosis

    PubMed Central

    Jiang, Zhao-Xin; Qiu, Suo; Lou, Bing-Sheng; Yang, Yao; Wang, Wen-Cong; Lin, Xiao-Feng

    2016-01-01

    Neutrophils have been recognized as critical response cells during the pathogenesis of endotoxin-induced uveitis (EIU). Apoptosis of neutrophils induced by roscovitine has previously been demonstrated to ameliorate inflammation in several in vivo models. The present study aimed to assess whether roscovitine ameliorates EIU. EIU was induced in female C57BL/6 mice by a single intravitreal injection of lipopolysaccharide (LPS; 250 ng). The mice were divided into three groups as follows: LPS alone, LPS plus vehicle, LPS plus roscovitine (50 mg/kg). The mice were euthanized 12, 24, 48 and 72 h after LPS-induced uveitis. Accumulation of inflammatory cells in the vitreous body was confirmed by immunohistochemistry, and quantified following hematoxylin and eosin staining. Terminal deoxynucleotidyl transferase dUTP nick-end labeling was performed to detect of apoptotic cells. The mRNA levels of inflammatory cytokines were analyzed by reverse transcription-quantitative polymerase chain reaction and the changes in protein levels were analyzed by western blotting. Inflammatory cells accumulated in the vitreous near the optic nerve head and the quantity peaked at 24 h after LPS injection. Immunohistochemistry revealed that the majority of the inflammatory cells were neutrophils. The number of infiltrating cells was similar in the LPS and LPS plus vehicle groups, while there were significantly less in the roscovitine group at 24 h. Apoptosis of neutrophils was observed between 12 and 48 h after roscovitine injection, while no apoptosis was observed in the other groups. The mRNA expression levels of GMCSF, CINC-1 and ICAM-1 peaked at 12 h after LPS injection, and decreased to normal levels at 72 h. This trend in mRNA expression was similar in the LPS and LPS plus vehicle groups; however, the expression levels decreased more quickly in the roscovitine group at 24 and 48 h. Following roscovitine administration, upregulated cleaved caspase 3 expression levels and downregulated Mcl-1

  1. Apoptosis-induced mitochondrial dysfunction causes cytoplasmic lipid droplet formation.

    PubMed

    Boren, J; Brindle, K M

    2012-09-01

    A characteristic of apoptosis is the rapid accumulation of cytoplasmic lipid droplets, which are composed largely of neutral lipids. The proton signals from these lipids have been used for the non-invasive detection of cell death using magnetic resonance spectroscopy. We show here that despite an apoptosis-induced decrease in the levels and activities of enzymes involved in lipogenesis, which occurs downstream of p53 activation and inhibition of the mTOR signaling pathway, the increase in lipid accumulation is due to increased de novo lipid synthesis. This results from inhibition of mitochondrial fatty acid β-oxidation, which coupled with an increase in acyl-CoA synthetase activity, diverts fatty acids away from oxidation and into lipid synthesis. The inhibition of fatty acid oxidation can be explained by a rapid rise in mitochondrial membrane potential and an attendant increase in the levels of reactive oxygen species. PMID:22460322

  2. Ceramide-Induced Apoptosis in Renal Tubular Cells: A Role of Mitochondria and Sphingosine-1-Phoshate

    PubMed Central

    Ueda, Norishi

    2015-01-01

    Ceramide is synthesized upon stimuli, and induces apoptosis in renal tubular cells (RTCs). Sphingosine-1 phosphate (S1P) functions as a survival factor. Thus, the balance of ceramide/S1P determines ceramide-induced apoptosis. Mitochondria play a key role for ceramide-induced apoptosis by altered mitochondrial outer membrane permeability (MOMP). Ceramide enhances oligomerization of pro-apoptotic Bcl-2 family proteins, ceramide channel, and reduces anti-apoptotic Bcl-2 proteins in the MOM. This process alters MOMP, resulting in generation of reactive oxygen species (ROS), cytochrome C release into the cytosol, caspase activation, and apoptosis. Ceramide regulates apoptosis through mitogen-activated protein kinases (MAPKs)-dependent and -independent pathways. Conversely, MAPKs alter ceramide generation by regulating the enzymes involving ceramide metabolism, affecting ceramide-induced apoptosis. Crosstalk between Bcl-2 family proteins, ROS, and many signaling pathways regulates ceramide-induced apoptosis. Growth factors rescue ceramide-induced apoptosis by regulating the enzymes involving ceramide metabolism, S1P, and signaling pathways including MAPKs. This article reviews evidence supporting a role of ceramide for apoptosis and discusses a role of mitochondria, including MOMP, Bcl-2 family proteins, ROS, and signaling pathways, and crosstalk between these factors in the regulation of ceramide-induced apoptosis of RTCs. A balancing role between ceramide and S1P and the strategy for preventing ceramide-induced apoptosis by growth factors are also discussed. PMID:25751724

  3. Enhancement of Cytotoxicity of Three Apoptosis-inducing Agents Against Human Oral Squamous Cell Carcinoma Cell Line by Benzoxazinotropone.

    PubMed

    Tomikoshi, Yukiko; Nomura, Maki; Okudaira, Noriyuki; Sakagami, Hiroshi; Wakabayashi, Hidetsugu

    Tumor-specificity (TS) and anti-inflammatory activity of benzo[b]cyclohept[e][1,4]oxazin-6(11H)-one, generally known as benzoxazinotropone (BOT), have been reported. In order to find a new biological activity, the combination effect of BOT and three apoptosis-inducing agents was investigated. Cytotoxicity against four human oral squamous cell carcinoma (OSCC) cell lines and five human oral normal cells (gingival fibroblasts, periodontal ligament fibroblasts, pulp cells, oral keratinocytes and primary gingival epithelial cells) was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. TS was evaluated by the ratio of the mean 50% cytotoxic concentration (CC50) against normal oral cells to the one against OSCC cell lines. Synergy was evaluated by CompuSyn software program. Expression of cleaved forms of poly ADP-ribose polymerase and caspsase-3 was evaluated by western blot analysis. BOT induced activation of caspase 3, suggesting the apoptosis induction in HSC-2 OSCC cells. BOT enhanced the cytotoxicity of doxorubicin (DXR) additively and that of curcumin and resveratrol synergistically. On the other hand, BOT did not enhance, but rather inhibit the cytotoxicity of DXR against normal keratinocytes. The present study suggests that BOT may enhance the anti-tumor activity of apoptosis-inducing agents, while reducing its cytotoxicity against normal cells. PMID:27566085

  4. Cimetidine induces apoptosis of human salivary gland tumor cells.

    PubMed

    Fukuda, Masakatsu; Tanaka, Shin; Suzuki, Seiji; Kusama, Kaoru; Kaneko, Tadayoshi; Sakashita, Hideaki

    2007-03-01

    It has been reported that cimetidine, a histamine type-2 receptor (H2R) antagonist, inhibits the growth of glandular tumors such as colorectal cancer. However, its effects against salivary gland tumors are still unknown. We demonstrated previously that human salivary gland tumor (HSG) cells spontaneously express the neural cell adhesion molecule (NCAM) and also that HSG cell proliferation could be controlled via a homophilic (NCAM-NCAM) binding mechanism and that NCAM may be associated with perineural invasion by malignant salivary gland tumors. In the present study, we investigated the effects of cimetidine via the expression of NCAM on tumor growth and perineural/neural invasion in salivary gland tumor cells. Expression of both NCAM mRNA and protein was found to decrease in a dose-dependent manner upon treatment with cimetidine for 24 h. The MTT assay and confocal laser microscopy clearly showed that HSG cells underwent apoptosis after treatment with cimetidine. Activation of caspases 3, 7, 8 and 9 was observed in HSG cells after cimetidine treatment, thus confirming that the apoptosis was induced by the activated caspases. Apaf-1 activity was also detected in HSG cells in a dose-dependent manner after treatment with cimetidine. We also found that the cimetidine-mediated down-regulation of NCAM expression in HSG cells did not occur via blocking of the histamine receptor, even though H2R expression was observed on HSG cells, as two other H2R antagonists, famotidine and ranitidine, did not show similar effects. We demonstrated for the first time that cimetidine can induce significant apoptosis of salivary gland tumor cells, which express NCAM, at least in part by down-regulation of NCAM expression on the cells. These findings suggest that the growth, development and perineural/neural invasion of salivary gland tumor cells can be blocked by cimetidine administration through down-regulation of NCAM expression, as well as induction of apoptosis. PMID:17273750

  5. AIRE-induced apoptosis is associated with nuclear translocation of stress sensor protein GAPDH

    SciTech Connect

    Liiv, Ingrid; Haljasorg, Uku; Kisand, Kai; Maslovskaja, Julia; Laan, Martti; Peterson, Paert

    2012-06-22

    Highlights: Black-Right-Pointing-Pointer AIRE induces apoptosis in epithelial cells. Black-Right-Pointing-Pointer CARD domain of AIRE is sufficient for apoptosis induction. Black-Right-Pointing-Pointer AIRE induced apoptosis involves GAPDH translocation to the nuclei. Black-Right-Pointing-Pointer Deprenyl inhibits AIRE induced apoptosis. -- Abstract: AIRE (Autoimmune Regulator) has a central role in the transcriptional regulation of self-antigens in medullary thymic epithelial cells, which is necessary for negative selection of autoreactive T cells. Recent data have shown that AIRE can also induce apoptosis, which may be linked to cross-presentation of these self-antigens. Here we studied AIRE-induced apoptosis using AIRE over-expression in a thymic epithelial cell line as well as doxycycline-inducible HEK293 cells. We show that the HSR/CARD domain in AIRE together with a nuclear localization signal is sufficient to induce apoptosis. In the nuclei of AIRE-positive cells, we also found an increased accumulation of a glycolytic enzyme, glyceraldehyde-3-phosphate (GAPDH) reflecting cellular stress and apoptosis. Additionally, AIRE-induced apoptosis was inhibited with an anti-apoptotic agent deprenyl that blocks GAPDH nitrosylation and nuclear translocation. We propose that the AIRE-induced apoptosis pathway is associated with GAPDH nuclear translocation and induction of NO-induced cellular stress in AIRE-expressing cells.

  6. GSI promotes vincristine-induced apoptosis by enhancing multi-polar spindle formation.

    PubMed

    Singh, Akannsha; Zapata, Mariana C; Choi, Yong Sung; Yoon, Sun-Ok

    2014-01-01

    Gamma secretase inhibitors (GSI), cell-permeable small-molecule inhibitors of gamma secretase activity, had been originally developed for the treatment of Alzheimer disease. In recent years, it has been exploited in cancer research to inhibit Notch signaling that is aberrantly activated in various cancers. We previously found that GSI could synergize with anti-microtubule agent, vincristine (VCR) in a Notch-independent manner. Here, we delineate the underlying cell cycle-related mechanism using HeLa cells, which have strong mitotic checkpoints. GSI enhanced VCR-induced cell death, although GSI alone did not affect cell viability at all. GSI augmented VCR-induced mitotic arrest in a dose-dependent manner, which was preceded by apoptotic cell death, as shown by an increase in Annexin V-positive and caspase-positive cell population. Furthermore, GSI amplified multi-polar spindle formation triggered by VCR. Altogether, we show the evidence that GSI enhances VCR-induced apoptosis in HeLa cells via multi-polar mitotic spindle formation, independent of Notch signaling. These data suggest that one or more GS substrates, yet to be identified, in a post-GS processed form, may play a role in maintaining functional centrosomes/mitotic spindles. More significantly, the synergistic effect of GSI in combination with VCR could be exploited in clinical setting to improve the efficacy of VCR. PMID:24200971

  7. Gefitinib induces lung cancer cell autophagy and apoptosis via blockade of the PI3K/AKT/mTOR pathway

    PubMed Central

    ZHAO, ZHONG-QUAN; YU, ZHONG-YANG; LI, JIE; OUYANG, XUE-NONG

    2016-01-01

    Gefitinib is a selective inhibitor of the tyrosine kinase epidermal growth factor receptor, which inhibits tumor pathogenesis, metastasis and angiogenesis, as well as promoting apoptosis. Therefore, gefitinib presents an effective drug for the targeted therapy of lung cancer. However, the underlying mechanisms by which gefitinib induces lung cancer cell death remain unclear. To investigate the effects of gefitinib on lung cancer cells and the mechanism of such, the present study analyzed the effect of gefitinib on the autophagy, apoptosis and proliferation of the A549 and A549-gefitinib-resistant (GR) cell lines GR. The regulation of the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/ mammalian target of rapamycin (mTOR) pathway was also investigated. Acridine orange staining revealed that gefitinib induced autophagy of A549 cells but not A549-GR cells. In addition, gefitinib promoted apoptosis and inhibited proliferation of A549 cells but not A549-GR cells. Furthermore, western blot analysis demonstrated that gefitinib treatment led to the downregulation of PI3K, AKT, pAKT, mTOR and phosphorylated-mTOR protein expression in A549 cells but not A549-GR cells. LY294002 blocked the PI3K/AKT/mTOR pathway and induced autophagy and apoptosis of A549 cells, however, no synergistic effect was observed following combined treatment with gefitinib and LY294002. In conclusion, the results of the present study indicate that gefitinib promotes autophagy and apoptosis of lung cancer cells via blockade of the PI3K/AKT/mTOR pathway, which leads to lung cancer cell death. PMID:27347100

  8. Cyclin-dependent kinase inhibitors sensitize tumor cells to nutlin-induced apoptosis: a potent drug combination.

    PubMed

    Cheok, Chit Fang; Dey, Anwesha; Lane, David P

    2007-11-01

    Current chemotherapy focuses on the use of genotoxic drugs that may induce general DNA damage in cancer cells but also high levels of toxicity in normal tissues. Nongenotoxic activation of p53 by targeting specific molecular pathways therefore provides an attractive therapeutic strategy in cancers with wild-type p53. Here, we explored the antitumor potential of cyclin-dependent kinase (CDK) inhibitors in combination with a small molecule inhibitor of p53-murine double minute 2 (MDM2) interaction. We show that low doses of CDK inhibitors roscovitine and DRB synergize with the MDM2 antagonist nutlin-3a in the induction of p53 activity and promote p53-dependent apoptosis in a dose- and time-dependent manner. Statistical measurement of the combination effects shows that the drug combination is additive on the reduction of cell viability and synergistic on inducing apoptosis, a critical end point of cytotoxic drugs. The degree of apoptosis observed 24 to 48 h after drug treatment correlated with the accumulation of p53 protein and concomitant induction of proapoptotic proteins Puma and PIG3. The antiproliferative and cytotoxic effects of this drug combination are validated in a range of tumor-derived cells including melanoma, colon carcinoma, breast adenocarcinoma, and hepatocarcinoma cells. Furthermore, this drug combination does not induce phosphorylation of Ser(15) on p53 and does not induce genotoxic stress in the cell. Given that many cytotoxic drugs rely on their ability to induce apoptosis via DNA damage-mediated activation of p53, the data presented here may provide a new therapeutic approach for the use of CDK inhibitors and MDM2 antagonists in combinatorial drug therapy. PMID:18025259

  9. Tetranectin gene deletion induces Parkinson's disease by enhancing neuronal apoptosis.

    PubMed

    Chen, Zhifeng; Wang, Ersong; Hu, Rong; Sun, Yu; Zhang, Lei; Jiang, Jue; Zhang, Ying; Jiang, Hong

    Parkinson's disease (PD) is a chronic neurodegenerative disorder characterized by the progressive degeneration of dopaminergic neurons in the substantia nigra pars compacta (SNpc). We previously identified tetranectin (TET) as a potential biomarker for PD whose expression is downregulated in the cerebrospinal fluid of PD patients. In the present study, we investigate the role of TET in neurodegeneration in vitro and in vivo. Our results showed that siRNA knockdown of TET decreased cell viability and the number of tyrosine hydroxylase (TH) positive cells, whereas it increased caspase-3 activity and the Bax/Bcl-2 ratio in cultured primary dopaminergic neurons. Overexpression of TET protected dopaminergic neurons against neuronal apoptosis in 1-methyl-4-phenylpyridinium cell culture model in vitro. In TET knockdown mouse model of PD, TET gene deletion decreased the number of TH positive cells in the SNpc, induced apoptosis via the p53/Bax pathway, and significantly impaired the motor behavior of transgenic mice. The findings suggest that TET plays a neuroprotective role via reducing neuron apoptosis and could be a valuable biomarker or potential therapeutic target for the treatment of patients with PD. PMID:26597345

  10. Diethanolamine alters neurogenesis and induces apoptosis in fetal mouse hippocampus

    PubMed Central

    Craciunescu, Corneliu N.; Wu, Renan; Zeisel, Steven H.

    2006-01-01

    Diethanolamine (DEA) is present in many consumer products such as shampoo. Dermal administration of DEA diminishes hepatic stores of the essential nutrient choline, and we previously reported that dietary choline deficiency during pregnancy reduces neurogenesis and increases apoptosis in the hippocampus of fetal rats and mice. Therefore, DEA could also alter brain development. Timed-pregnant C57BL/6 mice were dosed dermally from gestation day 7 through 17 with DEA at 0, 20, 80, 160, 320, and 640 mg/kg body/day. At doses of DEA > 80 mg/kg body/day, we observed decreased litter size. In fetuses (embryonic day 17) collected from dams treated dermally with 80 mg/kg body/day DEA, we observed decreased neural progenitor cell mitosis at the ventricular surface of the ventricular zone of the hippocampus [to 56±14% (SE) histone 3 (H3) phosphorylation as compared to controls; P < 0.01]. We also observed increased apoptosis in fetal hippocampus (to 170±10% of control measured using TUNEL and to 178±7% of control measured using activated caspase 3; P < 0.01). Thus, maternal exposure to DEA reduces the number of neural progenitor cells in hippocampus by two mechanisms, and this could permanently alter memory function in offspring of mothers exposed to this common ingredient of shampoos and soaps.—Craciunescu, C. N., Wu, R., Zeisel, S. H. Diethanolamine alters neurogenesis and induces apoptosis in fetal mouse hippocampus. PMID:16873886

  11. Dihydrolipoic acid induces cytotoxicity in mouse blastocysts through apoptosis processes.

    PubMed

    Houng, Wei-Li; Lin, Cheng-An J; Shen, Ji-Lin; Yeh, Hung-I; Wang, Hsueh-Hsiao; Chang, Walter H; Chan, Wen-Hsiung

    2012-01-01

    α-Lipoic acid (LA) is a thiol with antioxidant properties that protects against oxidative stress-induced apoptosis. LA is absorbed from the diet, taken up by cells and tissues, and subsequently reduced to dihydrolipoic acid (DHLA). In view of the recent application of DHLA as a hydrophilic nanomaterial preparation, determination of its biosafety profile is essential. In the current study, we examined the cytotoxic effects of DHLA on mouse embryos at the blastocyst stage, subsequent embryonic attachment and outgrowth in vitro, in vivo implantation by embryo transfer, and early embryonic development in an animal model. Blastocysts treated with 50 μM DHLA exhibited significantly increased apoptosis and a corresponding decrease in total cell number. Notably, the implantation success rates of blastocysts pretreated with DHLA were lower than that of their control counterparts. Moreover, in vitro treatment with 50 μM DHLA was associated with increased resorption of post-implantation embryos and decreased fetal weight. Data obtained using an in vivo mouse model further disclosed that consumption of drinking water containing 100 μM DHLA led to decreased early embryo development, specifically, inhibition of development to the blastocyst stage. However, it appears that concentrations of DHLA lower than 50 μM do not exert a hazardous effect on embryonic development. Our results collectively indicate that in vitro and in vivo exposure to concentrations of DHLA higher than 50 μM DHLA induces apoptosis and retards early pre- and post-implantation development, and support the potential of DHLA to induce embryonic cytotoxicity. PMID:22489194

  12. Fluoxetine synergizes with temozolomide to induce the CHOP-dependent endoplasmic reticulum stress-related apoptosis pathway in glioma cells

    PubMed Central

    Ma, Jian; Yang, Yan-Ru; Chen, Wei; Chen, Mei-Hua; Wang, Hao; Wang, Xiao-Dan; Sun, Li-Li; Wang, Feng-Ze; Wang, De-Cai

    2016-01-01

    Although temozolomide (TMZ) is the most effective chemotherapy agent for glioma, chemotherapy resistance has limited its clinical use. Fluoxetine (FLT), which is widely used in cancer-related depression, has exhibited potent anticancer properties in different cancer cell types. The aim of this study was i) to evaluate the antitumor mechanism of FLT, and ii) to further evaluate the effects of a combination of FLT and TMZ on glioma cells. Glioma cell lines were exposed to FLT and/or TMZ. Cell viability and apoptosis were examined by CCK-8 assay, flow cytometry and caspase-3 activity assay, respectively. The expression of endoplasmic reticulum-stress (ERS) apoptosis-related proteins was measured using real-time PCR and western blotting. Synergism between the two drugs was evaluated by the combination index (CI) through CompuSyn software. FLT significantly and dose-dependently inhibited the proliferation of various glioma cell lines, and rat glioma C6 cells had a highly sensitive response to the addition of FLT. FLT treatment increased the early apoptosis rate, induced typical apoptotic morphology in the C6 cells and activated caspase-3 with no change in the mitochondrial membrane potential. Further study showed that FLT activated the ERS marker, CHOP. This induction was associated with activation of the PERK-eIF2α-ATF4 and ATF6 cascade. Concomitantly, GADD34, a downstream molecule of CHOP, was also increased. Combined FLT and TMZ treatment showed a synergistic cytotoxic effect in the C6 glioma cells. Knockdown of CHOP expression abolished the synergistic effect of FLT and TMZ in the C6 cells, which suggests that FLT may sensitize glioma cells to TMZ through activation of the CHOP-dependent apoptosis pathway. These results revealed that FLT induced glioma cell apoptosis and sensitized glioma cells to TMZ through activation of the CHOP-dependent apoptosis pathway. The present study provides a primary basis for using the combination of these drugs in patients with

  13. Fluoxetine synergizes with temozolomide to induce the CHOP-dependent endoplasmic reticulum stress-related apoptosis pathway in glioma cells.

    PubMed

    Ma, Jian; Yang, Yan-Ru; Chen, Wei; Chen, Mei-Hua; Wang, Hao; Wang, Xiao-Dan; Sun, Li-Li; Wang, Feng-Ze; Wang, De-Cai

    2016-08-01

    Although temozolomide (TMZ) is the most effective chemotherapy agent for glioma, chemotherapy resistance has limited its clinical use. Fluoxetine (FLT), which is widely used in cancer-related depression, has exhibited potent anticancer properties in different cancer cell types. The aim of this study was i) to evaluate the antitumor mechanism of FLT, and ii) to further evaluate the effects of a combination of FLT and TMZ on glioma cells. Glioma cell lines were exposed to FLT and/or TMZ. Cell viability and apoptosis were examined by CCK-8 assay, flow cytometry and caspase-3 activity assay, respectively. The expression of endoplasmic reticulum-stress (ERS) apoptosis-related proteins was measured using real-time PCR and western blotting. Synergism between the two drugs was evaluated by the combination index (CI) through CompuSyn software. FLT significantly and dose-dependently inhibited the proliferation of various glioma cell lines, and rat glioma C6 cells had a highly sensitive response to the addition of FLT. FLT treatment increased the early apoptosis rate, induced typical apoptotic morphology in the C6 cells and activated caspase-3 with no change in the mitochondrial membrane potential. Further study showed that FLT activated the ERS marker, CHOP. This induction was associated with activation of the PERK-eIF2α-ATF4 and ATF6 cascade. Concomitantly, GADD34, a downstream molecule of CHOP, was also increased. Combined FLT and TMZ treatment showed a synergistic cytotoxic effect in the C6 glioma cells. Knockdown of CHOP expression abolished the synergistic effect of FLT and TMZ in the C6 cells, which suggests that FLT may sensitize glioma cells to TMZ through activation of the CHOP-dependent apoptosis pathway. These results revealed that FLT induced glioma cell apoptosis and sensitized glioma cells to TMZ through activation of the CHOP‑dependent apoptosis pathway. The present study provides a primary basis for using the combination of these drugs in patients with

  14. 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

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

    PubMed

    Huang, Huarong; Chen, Xuan; 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

  16. Vanadate induces apoptosis in epidermal JB6 P+ cells via hydrogen peroxide-mediated reactions.

    PubMed

    Ye, J; Ding, M; Leonard, S S; Robinson, V A; Millecchia, L; Zhang, X; Castranova, V; Vallyathan, V; Shi, X

    1999-12-01

    Apoptosis is a physiological mechanism for the control of DNA integrity in mammalian cells. Vanadium induces both DNA damage and apoptosis. It is suggested that vanadium-induced apoptosis serves to eliminate DNA-damaged cells. This study is designed to clarify a role of reactive oxygen species in the mechanism of apoptosis induced by vanadium. We established apoptosis model with murine epidermal JB6 P+ cells in the response to vanadium stimulation. Apoptosis was detected by a cell death ELISA assay and morphological analysis. The result shows that apoptosis induced by vanadate is dose-dependent, reaching its saturation level at a concentration of 100 microM vanadate. Vanadyl (IV) can also induce apoptosis albeit with lesser potency. A role of reactive oxygen species was analyzed by multiple reagents including specific scavengers of different reactive oxygen species. The result shows that vanadate-induced apoptosis is enhanced by NADPH, superoxide dismutase and sodium formate, but was inhibited by catalase and deferoxamine. Cells exposed to vanadium consume more molecular oxygen and at the same time, produce more H2O2 as measured by the change in fluorescence of scopoletin in the presence of horseradish peroxidase. This change in oxygen consumption and H2O2 production is enhanced by NADPH. Taken together, these results show that vanadate induces apoptosis in epidermal cells and H2O2 induced by vanadate plays a major role in this process. PMID:10705990

  17. Fangchinoline inhibits breast adenocarcinoma proliferation by inducing apoptosis.

    PubMed

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

    2011-01-01

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

  18. Cupressus lusitanica (Cupressaceae) leaf extract induces apoptosis in cancer cells.

    PubMed

    Lopéz, L; Villavicencio, M A; Albores, A; Martínez, M; de la Garza, J; Meléndez-Zajgla, J; Maldonado, V

    2002-05-01

    A crude ethanolic extract of Cupressus lusitanica Mill. leaves demonstrate cytotoxicity in a panel of cancer cell lines. Cell death was due to apoptosis, as assessed by morphologic features (chromatin condensation and apoptotic bodies formation) and specific DNA fragmentation detected by in situ end-labeling of DNA breaks (TUNEL). The apoptotic cell death was induced timely in a dose-dependent manner. Despite the absence of changes in the expression levels of antiapoptotic protein Bcl-2, proapoptotic Bax protein variants omega and delta were increased. These results warrant further research of possible antitumor compounds in this plant. PMID:12007700

  19. Ginsenoside compound K sensitizes human colon cancer cells to TRAIL-induced apoptosis via autophagy-dependent and -independent DR5 upregulation.

    PubMed

    Chen, Lei; Meng, Yue; Sun, Qi; Zhang, Zhongyu; Guo, Xiaoqing; Sheng, Xiaotong; Tai, Guihua; Cheng, Hairong; Zhou, Yifa

    2016-01-01

    Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is a potent cancer cell-specific apoptosis-inducing cytokine with little toxicity to most normal cells. However, acquired resistance of cancer cells to TRAIL is a roadblock. Agents that can either potentiate the effect of TRAIL or overcome resistance to TRAIL are urgently needed. This article reports that ginsenoside compound K (CK) potentiates TRAIL-induced apoptosis in HCT116 colon cancer cells and sensitizes TRAIL-resistant colon cancer HT-29 cells to TRAIL. On a cellular mechanistic level, CK downregulated cell survival proteins including Mcl-1, Bcl-2, surviving, X-linked inhibitor of apoptosis protein and Fas-associated death domain-like IL-1-converting enzyme-inhibitory protein, upregulated cell pro-apoptotic proteins including Bax, tBid and cytochrome c, and induced the cell surface expression of TRAIL death receptor DR5. Reduction of DR5 levels by siRNAs significantly decreases CK- and TRAIL-mediated apoptosis. Importantly, our results indicate, for the first time, that DR5 upregulation is mediated by autophagy, as blockade of CK-induced autophagy by 3-MA, LY294002 or Atg7 siRNAs substantially decreases DR5 upregulation and reduces the synergistic effect. Furthermore, CK-stimulated autophagy is mediated by the reactive oxygen species-c-Jun NH2-terminal kinase pathway. Moreover, we found that p53 and the C/EBP homologous (CHOP) protein is also required for DR5 upregulation but not related with autophagy. Our findings contribute significantly to the understanding of the mechanism accounted for the synergistic anticancer activity of CK and TRAIL, and showed a novel mechanism related with DR5 upregulation. PMID:27512955

  20. Combination of S-allylcysteine and lycopene induces apoptosis by modulating Bcl-2, Bax, Bim and caspases during experimental gastric carcinogenesis.

    PubMed

    Velmurugan, B; Mani, A; Nagini, S

    2005-08-01

    Combination chemoprevention by diet-derived agents that induce apoptosis is a promising strategy to control gastric cancer, the second most common malignancy worldwide. The present study was undertaken to investigate the apoptosis-inducing potential of a combination of S-allylcysteine (SAC), an organosulphur constituent of garlic and lycopene, a tomato carotenoid during N-methyl-N'-nitro-N-nitroso-guanidine (MNNG) and saturated sodium chloride (S-NaCl)-induced gastric carcinogenesis in Wistar rats using the apoptosis-associated proteins Bcl-2, Bax, Bim, caspase 8 and caspase 3 as markers. Animals administered MNNG followed by S-NaCl developed squamous cell carcinomas of the stomach associated with increased Bcl-2 expression and decreased expression of Bax, Bim, caspase 8 and caspase 3. Although SAC and lycopene alone significantly suppressed the development of gastric cancer, administration of SAC and lycopene in combination was more effective in inhibiting MNNG-induced stomach tumours and modulating the expression of apoptosis-associated proteins. Our results suggest that induction of apoptosis by SAC and lycopene combination represents one of the possible mechanisms that could account for their synergistic chemopreventive activity against gastric cancer. PMID:16030430

  1. Tris (dibenzylideneacetone) dipalladium: a small-molecule palladium complex is effective in inducing apoptosis in chronic lymphocytic leukemia B-cells.

    PubMed

    Kay, Neil E; Sassoon, Traci; Secreto, Charla; Sinha, Sutapa; Shanafelt, Tait D; Ghosh, Asish K; Arbiser, Jack L

    2016-10-01

    Here we tested impact of Tris (dibenzylideneacetone) dipalladium (Tris-DBA) on chronic lymphocytic leukemia (CLL) B-cell survival. Indeed, treatment of CLL B-cells with Tris-DBA induced apoptosis in a dose-dependent manner irrespective of IgVH mutational status. Further analyses suggest that Tris-DBA-induced apoptosis involves reduced expression of the anti-apoptotic proteins Bcl-xL, and XIAP with an upregulation of the pro-apoptotic protein BIM in CLL B-cells. Our findings also indicate that Tris-DBA targets the ribosomal protein (rp)-S6, an essential component of the Akt/mTOR signaling axis in CLL B-cells. Of interest, CLL bone marrow stromal cells were unable to protect the leukemic B cells from Tris-DBA-induced apoptosis in an in vitro co-culture system. Finally, co-administration of Tris-DBA and the purine nucleoside analog fludarabine (F-ara-A) augmented CLL B-cell apoptosis levels in vitro showing synergistic effects. In total, Tris-DBA is effective at inducing apoptosis in CLL B-cells even in the presence of stromal cells likely by targeting directly the signal mediator, rpS6. PMID:27189785

  2. Garcinia dulcis Fruit Extract Induced Cytotoxicity and Apoptosis in HepG2 Liver Cancer Cell Line.

    PubMed

    Abu Bakar, Mohd Fadzelly; Ahmad, Nor Ezani; Suleiman, Monica; Rahmat, Asmah; Isha, Azizul

    2015-01-01

    Garcinia dulcis or locally known in Malaysia as "mundu" belongs to the family of Clusiaceae. The study was conducted to investigate the anticancer potential of different parts of G. dulcis fruit extracts and their possible mechanism of action in HepG2 liver cancer cell line. MTT assay showed that the peel, flesh, and seed extracts of G. dulcis induced cytotoxicity in HepG2 cell line with IC50 values of 46.33 ± 4.51, 38.33 ± 3.51, and 7.5 ± 2.52 µg/mL, respectively. The flesh extract of G. dulcis induced cell cycle arrest at sub-G1 (apoptosis) phase in a time-dependent manner. Staining with Annexin V-FITC and propidium iodide showed that 41.2% of the cell population underwent apoptosis after 72 hours of exposure of the HepG2 cell line to G. dulcis flesh extract. Caspase-3 has been shown to be activated which finally leads to the death of HepG2 cell (apoptosis). GC-MS analysis showed that the highest percentage of compound identified in the extract of G. dulcis flesh was hydroxymethylfurfural and 3-methyl-2,5-furandione, together with xanthones and flavonoids (based on literature), could synergistically contribute to the observed effects. This finding suggested that the flesh extract of G. dulcis has its own potential as cancer chemotherapeutic agent against liver cancer cell. PMID:26557713

  3. Garcinia dulcis Fruit Extract Induced Cytotoxicity and Apoptosis in HepG2 Liver Cancer Cell Line

    PubMed Central

    Abu Bakar, Mohd Fadzelly; Ahmad, Nor Ezani; Suleiman, Monica; Rahmat, Asmah; Isha, Azizul

    2015-01-01

    Garcinia dulcis or locally known in Malaysia as “mundu” belongs to the family of Clusiaceae. The study was conducted to investigate the anticancer potential of different parts of G. dulcis fruit extracts and their possible mechanism of action in HepG2 liver cancer cell line. MTT assay showed that the peel, flesh, and seed extracts of G. dulcis induced cytotoxicity in HepG2 cell line with IC50 values of 46.33 ± 4.51, 38.33 ± 3.51, and 7.5 ± 2.52 µg/mL, respectively. The flesh extract of G. dulcis induced cell cycle arrest at sub-G1 (apoptosis) phase in a time-dependent manner. Staining with Annexin V-FITC and propidium iodide showed that 41.2% of the cell population underwent apoptosis after 72 hours of exposure of the HepG2 cell line to G. dulcis flesh extract. Caspase-3 has been shown to be activated which finally leads to the death of HepG2 cell (apoptosis). GC-MS analysis showed that the highest percentage of compound identified in the extract of G. dulcis flesh was hydroxymethylfurfural and 3-methyl-2,5-furandione, together with xanthones and flavonoids (based on literature), could synergistically contribute to the observed effects. This finding suggested that the flesh extract of G. dulcis has its own potential as cancer chemotherapeutic agent against liver cancer cell. PMID:26557713

  4. Synergistic cooperation between ABT-263 and MEK1/2 inhibitor: effect on apoptosis and proliferation of acute myeloid leukemia cells

    PubMed Central

    Airiau, Kelly; Prouzet-Mauléon, Valérie; Rousseau, Benoit; Pigneux, Arnaud; Jeanneteau, Marie; Giraudon, Manon; Allou, Kaoutar; Dubus, Pierre

    2016-01-01

    In spite of intensive research to improve treatment of acute myeloid leukemia (AML) more than half of all patients continue to develop a refractory disease. Therefore there is need to improve AML treatment. The overexpression of the BCL-2 family anti-apoptotic members, like BCL-2 or BCL-xL has been largely reported in lymphoid tumors but also in AML and other tumors. To counteract the anti-apoptotic effect of BCL-2, BH3 mimetics have been developed to target cancer cells. An increase in activity of ERK1/2 mitogen activated protein (MAP) kinase has also been reported in AML and might be targeted by MEK1/2 inhibitors. Hence, in the current work, we investigated whether the association of a BH3 mimetic such ABT-263 and the MEK1/2 inhibitor pimasertib (MEKI), was efficient to target AML cells. A synergistic increasing of apoptosis was observed in AML cell lines and in primary cells without affecting normal bone marrow cells. Such cooperation was confirmed on tumor growth in a mouse xenograft model of AML. In addition we demonstrated that MEKI sensitized the cells to apoptosis through its ability to promote a G1 cell cycle arrest. So, this combination of a MAP Kinase pathway inhibitor and a BH3 mimetic could be a promising strategy to improve the treatment of AML. PMID:26625317

  5. Non-thermal plasma with 2-deoxy-D-glucose synergistically induces cell death by targeting glycolysis in blood cancer cells

    NASA Astrophysics Data System (ADS)

    Kaushik, Neha; Lee, Su Jae; Choi, Tae Gyu; Baik, Ku Youn; Uhm, Han Sup; Kim, Chung Hyeok; Kaushik, Nagendra Kumar; Choi, Eun Ha

    2015-03-01

    In this study, we show the selective and efficient anti-cancer effects of plasma (at a low dose) when cell metabolic modifiers are also included. 2-deoxy-D-glucose (2-DG), a glycolytic inhibitor, was used with effective doses of non-thermal plasma, synergistically attenuating cell metabolic viability and inducing caspase-dependent and independent cell death. The combination treatment decreased the intracellular ATP and lactate production in various types of blood cancer cells in vitro. Taken together, our findings suggest that 2-DG enhances the efficacy and selectivity of plasma and induces the synergistic inhibition of cancer cell growth by targeting glycolysis and apoptosis. Specifically, this treatment strategy demonstrated an enhanced growth inhibitory effect of plasma in the presence of a metabolic modifier that was selective against cancer cells, not non-malignant cells. This is the first study to report the advantage of combining plasma with 2-DG to eradicate blood cancer cells. Finally, we conclude that 2-DG with non-thermal plasma may be used as a combination treatment against blood cancer cells.

  6. Study of apoptosis induced by cytostatics and vegetal extracts on human endothelial cell line.

    PubMed

    Bârzu, Simona Natalia; Bădulescu, Maria Mihaela; Lupu, Andreea Roxana; Cremer, Lidia; Szegli, G; Kerek, F; Călugăru, Ana

    2008-01-01

    Angiogenesis, the biological process by which new capillaries are formed from pre-existing vessels, is a tightly controlled and complex process involving several factors with both stimulating and inhibiting steps. In solid tumor growth, a specific clinical turning point is the transition to the vascular phase. Once it develops an intrinsic vascular network, a tumor grows indefinitely. Tumor angiogenesis depends mainly on the release by neoplasic cells of growth factors specific for endothelial cells (ECs), able to stimulate growth of the host blood vessels. The aim of this study was to analyze the apoptotic effect of some cytostatics, Vinblastine, Rapamycin and Doxorubicin, and vegetal extracts (called VOB) isolated and purified from Vitis sp., on human EA.hy926 endothelial cell line. In a proliferation assay using Crystal Violet, we demonstrated that Vinblastine and Rapamycin cytostatics have synergistic effect on endothelial cell line EA.hy926 growth inhibition. The inhibitory effects of Vinblastine and Doxorubicin were enhanced by VOB vegetal extracts. A combined treatment of cytostatics and VOB vegetal extracts resulted in a stronger antiproliferative effect of EA.hy926 endothelial cells. Results obtained regarding the apoptosis induced on EA.hy926 endothelial cells showed that each compound alone was able to induce a significant percent of apoptotic cells in a dose-dependent manner. PMID:19284159

  7. Tissue Tolerable Plasma (TTP) induces apoptosis in pancreatic cancer cells in vitro and in vivo

    PubMed Central

    2012-01-01

    Background The rate of microscopic incomplete resections of gastrointestinal cancers including pancreatic cancer has not changed considerably over the past years. Future intra-operative applications of tissue tolerable plasmas (TTP) could help to address this problem. Plasma is generated by feeding energy, like electrical discharges, to gases. The development of non-thermal atmospheric plasmas displaying spectra of temperature within or just above physiological ranges allows biological or medical applications of plasmas. Methods We have investigated the effects of tissue tolerable plasmas (TTP) on the human pancreatic cancer cell line Colo-357 and PaTu8988T and the murine cell line 6606PDA in vitro (Annexin-V-FITC/DAPI-Assay and propidium iodide DNA staining assay) as well as in the in vivo tumour chorio-allantoic membrane (TUM-CAM) assay using Colo-357. Results TTP of 20 seconds (s) induced a mild elevation of an experimental surface temperature of 23.7 degree Celsius up to 26.63+/−0.40 degree Celsius. In vitro TTP significantly (p=0.0003) decreased cell viability showing the strongest effects after 20s TTP. Also, TTP effects increased over time levelling off after 72 hours (30.1+/−4.4% of dead cells (untreated control) versus 78.0+/−9.6% (20s TTP)). However, analyzing these cells for apoptosis 10s TTP revealed the largest proportion of apoptotic cells (34.8+/−7.2%, p=0.0009 versus 12.3+/−6.6%, 20s TTP) suggesting non-apoptotic cell death in the majority of cells after 20s TTP. Using solid Colo-357 tumours in the TUM-CAM model TUNEL-staining showed TTP-induced apoptosis up to a depth of tissue penetration (DETiP) of 48.8+/−12.3μm (20s TTP, p<0.0001). This was mirrored by a significant (p<0.0001) reduction of Ki-67+ proliferating cells (80.9+/−13.2% versus 37.7+/−14.6%, p<0.0001) in the top cell layers as well as typical changes on HE specimens. The bottom cell layers were not affected by TTP. Conclusions Our data suggest possible future intra

  8. Gefitinib upregulates death receptor 5 expression to mediate rmhTRAIL-induced apoptosis in Gefitinib-sensitive NSCLC cell line

    PubMed Central

    Yan, Dong; Ge, Yang; Deng, Haiteng; Chen, Wenming; An, Guangyu

    2015-01-01

    Background Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) triggers apoptosis in tumor cells, but when used alone, it is not effective in the treatment of TRAIL-resistant tumors. Some studies have shown that gefitinib interacts with recombinant mutant human TRAIL (rmhTRAIL) to induce high levels of apoptosis in gefitinib-responsive bladder cancer cell lines; however, the molecular mechanisms underlying the anticancer effects are not fully understood. Several reports have shown that the death receptor 5 (DR5) plays an important role in sensitizing cancer cells to apoptosis induced by TRAIL. Therefore, we investigated the effects of the combination of drugs and the expression of the DR5 to analyze the growth of a gefitinib-responsive non-small cell lung cancer cell line PC9, which was treated with rmhTRAIL and gefitinib individually or in combination. Methods Human PC9 non-small cell lung cancer cells harboring an epidermal growth factor receptor mutation were used as a model for the identification of the therapeutic effects of gefitinib alone or in combination with rmhTRAIL, and cytotoxicity was assessed by MTT assays. Cell cycle and apoptosis were investigated using flow cytometry. Moreover, the effects of drugs on DR5, BAX, FLIP, and cleaved-caspase3 proteins expressions were analyzed using Western blot analyses. Finally, quantitative polymerase chain reaction analysis was carried out to assess whether rmhTRAIL and gefitinib modulate the expression of genes related to drug activity. Results Gefitinib and rmhTRAIL synergistically interact to inhibit cell proliferation, and apoptosis assessment demonstrated that associations of drug increased the apoptotic index. rmhTRAIL when used alone downregulated DR5 and upregulated BAX, FLIP, and cleaved-caspase3 proteins expressions. However, results obtained in Western blot analyses demonstrated that the combined treatment-induced cell apoptosis was achieved involving upregulated DR5, cleaved-caspase3, and

  9. A small molecule inhibitor of ubiquitin-specific protease-7 induces apoptosis in multiple myeloma cells and overcomes bortezomib resistance.

    PubMed

    Chauhan, Dharminder; Tian, Ze; Nicholson, Benjamin; Kumar, K G Suresh; Zhou, Bin; Carrasco, Ruben; McDermott, Jeffrey L; Leach, Craig A; Fulcinniti, Mariaterresa; Kodrasov, Matthew P; Weinstock, Joseph; Kingsbury, William D; Hideshima, Teru; Shah, Parantu K; Minvielle, Stephane; Altun, Mikael; Kessler, Benedikt M; Orlowski, Robert; Richardson, Paul; Munshi, Nikhil; Anderson, Kenneth C

    2012-09-11

    Bortezomib therapy has proven successful for the treatment of relapsed/refractory, relapsed, and newly diagnosed multiple myeloma (MM); however, dose-limiting toxicities and the development of resistance limit its long-term utility. Here, we show that P5091 is an inhibitor of deubiquitylating enzyme USP7, which induces apoptosis in MM cells resistant to conventional and bortezomib therapies. Biochemical and genetic studies show that blockade of HDM2 and p21 abrogates P5091-induced cytotoxicity. In animal tumor model studies, P5091 is well tolerated, inhibits tumor growth, and prolongs survival. Combining P5091 with lenalidomide, HDAC inhibitor SAHA, or dexamethasone triggers synergistic anti-MM activity. Our preclinical study therefore supports clinical evaluation of USP7 inhibitor, alone or in combination, as a potential MM therapy. PMID:22975377

  10. Nitroxoline induces apoptosis and slows glioma growth in vivo

    PubMed Central

    Lazovic, Jelena; Guo, Lea; Nakashima, Jonathan; Mirsadraei, Leili; Yong, William; Kim, Hyun J.; Ellingson, Benjamin; Wu, Hong; Pope, Whitney B.

    2015-01-01

    Background Nitroxoline is an FDA-approved antibiotic with potential antitumor activity. Here we evaluated whether nitroxoline has antiproliferative properties on glioma cell growth in vitro and in vivo using glioma cell lines and a genetically engineered PTEN/KRAS mouse glioma model. Methods The effect of nitroxoline treatment on U87 and/or U251 glioma cell proliferation, cell-cycle arrest, invasion, and ability to induce an apoptotic cascade was determined in vitro. Magnetic resonance imaging was used to measure glioma volumes in genetically engineered PTEN/KRAS mice prior to and after nitroxoline therapy. Induction of apoptosis by nitroxoline was evaluated at the end of treatment using terminal deoxyribonucleotidyl transferase (TDT)-mediated dUTP-digoxigenin nick end labeling (TUNEL). Results Nitroxoline inhibited the proliferation and invasion of glioblastoma cells in a time- and dose-dependent manner in vitro. Growth inhibition was associated with cell-cycle arrest in G1/G0 phase and induction of apoptosis via caspase 3 and cleaved poly(ADP-ribose) polymerase. In vivo, nitroxoline-treated mice had no increase in tumor volume after 14 days of treatment, whereas tumor volumes doubled in control mice. Histological examination revealed 15%–20% TUNEL-positive cells in nitroxoline-treated mice, compared with ∼5% in the control group. Conclusion Nitroxoline induces apoptosis and inhibits glioma growth in vivo and in vitro. As an already FDA-approved treatment for urinary tract infections with a known safety profile, nitroxoline could move quickly into clinical trials pending confirmatory studies. PMID:25074541