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Sample records for a2 mediated tumor

  1. Liposomes containing alkylated methotrexate analogues for phospholipase A(2) mediated tumor targeted drug delivery

    DEFF Research Database (Denmark)

    Kaasgaard, Thomas; Andresen, Thomas Lars; Jensen, Simon Skøde

    2009-01-01

    cytotoxicity was incorporated into liposomes that were designed to be particularly Susceptible to a liposome degrading enzyme, secretory phospholipase A(2) (sPLA(2)), which is found in high concentrations in tumors of several different cancer types. Liposome incorporation was investigated by differential...... scanning calorimetry (DSC), and sPLA(2) hydrolysis was examined by fluorescence spectroscopy and high performance liquid chromatography (HPLC). The results showed that the methotrexate (MTX)-analogue could be incorporated into liposomes that were degradable by sPLA(2). However, the in vitro cytotoxicity...... of the MTX-liposomes against KATO III and HT-29 cancer cells was found to be independent of sPLA(2) hydrolysis, indicating that the alkylated MTX-analogue was available for cancer cell uptake even in the absence of liposome hydrolysis. Using a DSC based method for assessing the anchoring stability...

  2. Antibody-Dependent Cell-Mediated Cytotoxicity Effector-Enhanced EphA2 Agonist Monoclonal Antibody Demonstrates Potent Activity against Human Tumors

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    Elizabeth M. Bruckheimer

    2009-06-01

    Full Text Available EphA2 is a receptor tyrosine kinase that has been shown to be overexpressed in a variety of human tumor types. Previous studies demonstrated that agonist monoclonal antibodies targeting EphA2 induced the internalization and degradation of the receptor, thereby abolishing its oncogenic effects. In this study, the in vitro and in vivo antibody-dependent cell-mediated cytotoxicity (ADCC activity of EphA2 effector-enhanced agonist monoclonal antibodies was evaluated. With tumor cell lines and healthy human peripheral blood monocytes, the EphA2 antibodies demonstrated ∼80% tumor cell killing. In a dose-dependent manner, natural killer (NK cells were required for the in vitro ADCC activity and became activated as demonstrated by the induction of cell surface expression of CD107a. To assess the role of NK cells on antitumor efficacy in vivo, the EphA2 antibodies were evaluated in xenograft models in severe compromised immunodeficient (SCID mice (which have functional NK cells and monocytes and SCID nonobese diabetic (NOD mice (which largely lack functional NK cells and monocytes. Dosing of EphA2 antibody in the SCID murine tumor model resulted in a 6.2-fold reduction in tumor volume, whereas the SCID/nonobese diabetic model showed a 1.6-fold reduction over the isotype controls. Together, these results demonstrate that the anti-EphA2 monoclonal antibodies may function through at least two mechanisms of action: EphA2 receptor activation and ADCC-mediated activity. These novel EphA2 monoclonal antibodies provide additional means by which host effector mechanisms can be activated for selective destruction of EphA2-expressing tumor cells.

  3. Cathepsins mediate tumor metastasis

    Institute of Scientific and Technical Information of China (English)

    Gong-Jun; Tan; Zheng-Ke; Peng; Jin-Ping; Lu; Fa-Qing; Tang

    2013-01-01

    Cathepsins are highly expressed in various human cancers, associated with tumor metastasis. It is superfamily, concluding A, B, C, D, E, F, G, H, L, K, O, S, V, and W family members. As a group of lysosomal proteinases or endopeptidases, each member has a different function, playing different roles in distinct tumorigenic processes such as proliferation, angiogenesis, metastasis, and invasion. Cathepsins belong to a diverse number of enzyme subtypes, including cysteine proteases, serine proteases and aspartic proteases. The contribution of cathepsins to invasion in human cancers is well documented, although the precise mechanisms by which cathepsins exert their effects are still not clear. In the present review, the role of cathepsin family members in cancer is discussed.

  4. HER-2/neu mediated down-regulation of MHC class I antigen processing prevents CTL-mediated tumor recognition upon DNA vaccination in HLA-A2 transgenic mice.

    Science.gov (United States)

    Vertuani, Simona; Triulzi, Chiara; Roos, Anna Karin; Charo, Jehad; Norell, Håkan; Lemonnier, François; Pisa, Pavel; Seliger, Barbara; Kiessling, Rolf

    2009-05-01

    To study DNA vaccination directed against human HER-2 in the HHD mouse Tg strain, we created a novel HER-2-expressing syngeneic tumor transplantation model. We found that a DNA vaccine encoding the full length HER-2 DNA protected HHD mice from HER-2(+) tumor challenge by a CTL independent mechanism. A more efficient approach to induce HLA-A2 restricted CTLs, through immunization with a multi-epitope DNA vaccine expressing the HLA-A2 restricted HER-2 369-377, 435-443 and 689-697 epitopes, resulted in high numbers of peptide specific T cells but failed to induce tumor protection. Subsequently we discovered that HER-2 transfected tumor cells down-regulated MHC class I antigen expression and exhibited a series of defects in the antigen processing pathway which impaired the capacity to produce and display MHC class I peptide-ligands to specific CTLs. Our data demonstrate that HER-2 transfection is associated with defects in the MHC class I presentation pathway, which may be the underlying mechanism behind the inability of CTLs to recognize tumors in this HLA-A2 transgenic model. As defective MHC class I presentation may be a common characteristic of HER-2 expressing tumors, vaccines targeting HER-2 should aim at inducing an integrated immune response where also CD4(+) T cells and antibodies are important components.

  5. Photodynamic therapy of a 2-methoxyestradiol tumor-targeting drug delivery system mediated by Asn-Gly-Arg in breast cancer

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    Shi J

    2013-04-01

    Full Text Available Jinjin Shi, Zhenzhen Wang, Lei Wang, Honghong Wang, Lulu Li, Xiaoyuan Yu, Jing Zhang, Rou Ma, Zhenzhong ZhangSchool of Pharmaceutical Sciences, Zhengzhou University, Zhengzhou, People's Republic of ChinaAbstract: Fullerene (C60 has shown great potential in drug delivery. In this study we exploited modified fullerene (diadduct malonic acid-fullerene-Asn-Gly-Arg peptide [DMA-C60-NGR] as an antitumor drug carrier in order to build a new tumor-targeting drug delivery system. We also investigated the synergistic enhancement of cancer therapy using photodynamic therapy (PDT induced by DMA-C60-NGR and 2-methoxyestradiol (2ME. Cytotoxicity tests indicated that DMA-C60-NGR had no obvious toxicity, while our drug delivery system (DMA-C60-2ME-NGR had a high inhibition effect on MCF-7 cells compared to free 2ME. The tumor-targeting drug delivery system could efficiently cross cell membranes, and illumination induced the generation of intracellular reactive oxygen species and DNA damage. Furthermore, DMA-C60-2ME-NGR with irradiation had the highest inhibition effect on MCF-7 cells compared to the other groups. DMA-C60-NGR combined with 2ME showed a good synergistic photosensitization effect for inhibiting the growth of MCF-7 cells, demonstrating that DMA-C60-2ME-NGR may be promising for high treatment efficacy with minimal side effects in future therapy.Keywords: fullerene, drug delivery system, photodynamic therapy, tumor targeting

  6. Autocrine IL-6 mediates pituitary tumor senescence

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

    2017-01-01

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

  7. Caffeine promotes anti-tumor immune response during tumor initiation: Involvement of the adenosine A2A receptor.

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    Eini, Hadar; Frishman, Valeria; Yulzari, Robert; Kachko, Leonid; Lewis, Eli C; Chaimovitz, Cidio; Douvdevani, Amos

    2015-11-01

    Epidemiologic studies depict a negative correlation between caffeine consumption and incidence of tumors in humans. The main pharmacological effects of caffeine are mediated by antagonism of the adenosine receptor, A2AR. Here, we examine whether the targeting of A2AR by caffeine plays a role in anti-tumor immunity. In particular, the effects of caffeine are studied in wild-type and A2AR knockout (A2AR(-/-)) mice. Tumor induction was achieved using the carcinogen 3-methylcholanthrene (3-MCA). Alternatively, tumor cells, comprised of 3-MCA-induced transformed cells or B16 melanoma cells, were inoculated into animal footpads. Cytokine release was determined in a mixed lymphocyte tumor reaction (MLTR). According to our findings, caffeine-consuming mice (0.1% in water) developed tumors at a lower rate compared to water-consuming mice (14% vs. 53%, respectively, p=0.0286, n=15/group). Within the caffeine-consuming mice, tumor-free mice displayed signs of autoimmune alopecia and pronounced leukocyte recruitment intocarcinogen injection sites. Similarly, A2AR(-/-) mice exhibited reduced rates of 3-MCA-induced tumors. In tumor inoculation studies, caffeine treatment resulted in inhibition of tumor growth and elevation in proinflammatory cytokine release over water-consuming mice, as depicted by MLTR. Addition of the adenosine receptor agonist, NECA, to MLTR resulted in a sharp decrease in IFNγ levels; this was reversed by the highly selective A2AR antagonist, ZM241385. Thus, immune response modulation through either caffeine or genetic deletion of A2AR leads to a Th1 immune profile and suppression of carcinogen-induced tumorigenesis. Taken together, our data suggest that the use of pharmacologic A2AR antagonists may hold therapeutic potential in diminishing the rate of cancer development.

  8. KSHV-Mediated Angiogenesis in Tumor Progression

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    Pravinkumar Purushothaman

    2016-07-01

    Full Text Available Human herpesvirus 8 (HHV-8, also known as Kaposi’s sarcoma-associated herpesvirus (KSHV, is a malignant human oncovirus belonging to the gamma herpesvirus family. HHV-8 is closely linked to the pathogenesis of Kaposi’s sarcoma (KS and two other B-cell lymphoproliferative diseases: primary effusion lymphoma (PEL and a plasmablastic variant of multicentric Castleman’s disease (MCD. KS is an invasive tumor of endothelial cells most commonly found in untreated HIV-AIDS or immuno-compromised individuals. KS tumors are highly vascularized and have abnormal, excessive neo-angiogenesis, inflammation, and proliferation of infected endothelial cells. KSHV directly induces angiogenesis in an autocrine and paracrine fashion through a complex interplay of various viral and cellular pro-angiogenic and inflammatory factors. KS is believed to originate due to a combination of KSHV’s efficient strategies for evading host immune systems and several pro-angiogenic and pro-inflammatory stimuli. In addition, KSHV infection of endothelial cells produces a wide array of viral oncoproteins with transforming capabilities that regulate multiple host-signaling pathways involved in the activation of angiogenesis. It is likely that the cellular-signaling pathways of angiogenesis and lymph-angiogenesis modulate the rate of tumorigenesis induction by KSHV. This review summarizes the current knowledge on regulating KSHV-mediated angiogenesis by integrating the findings reported thus far on the roles of host and viral genes in oncogenesis, recent developments in cell-culture/animal-model systems, and various anti-angiogenic therapies for treating KSHV-related lymphoproliferative disorders.

  9. KSHV-Mediated Angiogenesis in Tumor Progression

    Science.gov (United States)

    Purushothaman, Pravinkumar; Uppal, Timsy; Sarkar, Roni; Verma, Subhash C.

    2016-01-01

    Human herpesvirus 8 (HHV-8), also known as Kaposi’s sarcoma-associated herpesvirus (KSHV), is a malignant human oncovirus belonging to the gamma herpesvirus family. HHV-8 is closely linked to the pathogenesis of Kaposi’s sarcoma (KS) and two other B-cell lymphoproliferative diseases: primary effusion lymphoma (PEL) and a plasmablastic variant of multicentric Castleman’s disease (MCD). KS is an invasive tumor of endothelial cells most commonly found in untreated HIV-AIDS or immuno-compromised individuals. KS tumors are highly vascularized and have abnormal, excessive neo-angiogenesis, inflammation, and proliferation of infected endothelial cells. KSHV directly induces angiogenesis in an autocrine and paracrine fashion through a complex interplay of various viral and cellular pro-angiogenic and inflammatory factors. KS is believed to originate due to a combination of KSHV’s efficient strategies for evading host immune systems and several pro-angiogenic and pro-inflammatory stimuli. In addition, KSHV infection of endothelial cells produces a wide array of viral oncoproteins with transforming capabilities that regulate multiple host-signaling pathways involved in the activation of angiogenesis. It is likely that the cellular-signaling pathways of angiogenesis and lymph-angiogenesis modulate the rate of tumorigenesis induction by KSHV. This review summarizes the current knowledge on regulating KSHV-mediated angiogenesis by integrating the findings reported thus far on the roles of host and viral genes in oncogenesis, recent developments in cell-culture/animal-model systems, and various anti-angiogenic therapies for treating KSHV-related lymphoproliferative disorders. PMID:27447661

  10. Cell Mediated Photothermal Therapy of Brain Tumors.

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    Hirschberg, Henry; Madsen, Steen J

    2017-03-01

    Gold based nanoparticles with strong near infra-red (NIR) absorption are ideally suited for photothermal therapy (PTT) of brain tumors. The goal of PTT is to induce rapid heating in tumor tissues while minimizing thermal diffusion to normal brain. PTT efficacy is sensitively dependent on both nanoparticle concentration and distribution in tumor tissues. Nanoparticle delivery via passive approaches such as the enhanced permeability and retention (EPR) effect is unlikely to achieve sufficient nanoparticle concentrations throughout tumor volumes required for effective PTT. A simple approach for improving tumor biodsitribution of nanoparticles is the use of cellular delivery vehicles. Specifically, this review focuses on the use of monocytes/macrophages (Mo/Ma) as gold nanoparticle delivery vectors for PTT of brain tumors. Although the efficacy of this delivery approach has been demonstrated in both in vitro and animal PTT studies, its clinical potential for the treatment of brain tumors remains uncertain.

  11. Breast cancer associated a2 isoform vacuolar ATPase immunomodulates neutrophils: potential role in tumor progression.

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    Ibrahim, Safaa A; Katara, Gajendra K; Kulshrestha, Arpita; Jaiswal, Mukesh K; Amin, Magdy A; Beaman, Kenneth D

    2015-10-20

    In invasive breast cancer, tumor associated neutrophils (TAN) represent a significant portion of the tumor mass and are associated with increased angiogenesis and metastasis. Identifying the regulatory factors that control TAN behavior will help in developing ideal immunotherapies. Vacuolar ATPases (V-ATPases), multi-subunit proton pumps, are highly expressed in metastatic breast cancer cells. A cleaved peptide from a2 isoform V-ATPase (a2NTD) has immunomodulatory role in tumor microenvironment. Here, we report for the first time the role of V-ATPase in neutrophils modulation. In invasive breast cancer cells, a2NTD was detected and a2V was highly expressed on the surface. Immunohistochemical analysis of invasive breast cancer tissues revealed that increased neutrophil recruitment and blood vessel density correlated with increased a2NTD levels. In order to determine the direct regulatory role of a2NTD on neutrophils, recombinant a2NTD was used for the treatment of neutrophils isolated from the peripheral blood of healthy volunteers. Neutrophils treated with a2NTD (a2Neuɸ) showed increased secretion of IL-1RA, IL-10, CCL-2 and IL-6 that are important mediators in cancer related inflammation. Moreover, a2Neuɸ exhibited an increased production of protumorigenic factors including IL-8, matrix metaloprotinase-9 and vascular endothelial growth factor. Further, functional characterization of a2Neuɸ revealed that a2Neuɸ derived products induce in vitro angiogenesis as well as increase the invasiveness of breast cancer cells. This study establishes the modulatory effect of breast cancer associated a2V on neutrophils, by the action of a2NTD, which has a positive impact on tumor progression, supporting that a2V can be a potential selective target for breast cancer therapy.

  12. Angiocrine factors modulate tumor proliferation and motility through EphA2 repression of Slit2 tumor suppressor function in endothelium.

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    Brantley-Sieders, Dana M; Dunaway, Charlene M; Rao, Meghana; Short, Sarah; Hwang, Yoonha; Gao, Yandong; Li, Deyu; Jiang, Aixiang; Shyr, Yu; Wu, Jane Y; Chen, Jin

    2011-02-01

    It is well known that tumor-derived proangiogenic factors induce neovascularization to facilitate tumor growth and malignant progression. However, the concept of "angiocrine" signaling, in which signals produced by endothelial cells elicit tumor cell responses distinct from vessel function, has been proposed, yet remains underinvestigated. Here, we report that angiocrine factors secreted from endothelium regulate tumor growth and motility. We found that Slit2, which is negatively regulated by endothelial EphA2 receptor, is one such tumor suppressive angiocrine factor. Slit2 activity is elevated in EphA2-deficient endothelium. Blocking Slit activity restored angiocrine-induced tumor growth/motility, whereas elevated Slit2 impaired growth/motility. To translate our findings to human cancer, we analyzed EphA2 and Slit2 expression in human cancer. EphA2 expression inversely correlated with Slit2 in the vasculature of invasive human ductal carcinoma samples. Moreover, analysis of large breast tumor data sets revealed that Slit2 correlated positively with overall and recurrence-free survival, providing clinical validation for the tumor suppressor function for Slit2 in human breast cancer. Together, these data support a novel, clinically relevant mechanism through which EphA2 represses Slit2 expression in endothelium to facilitate angiocrine-mediated tumor growth and motility by blocking a tumor suppressive signal.

  13. Adenovirus-mediated gene transfer to tumor cells.

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    Cascalló, Manel; Alemany, Ramon

    2004-01-01

    Cell transduction in vitro is only the first step toward proving that a genetherapy vector can be useful to treat tumors. However, tumor targeting in vivo is now the milestone for gene therapy to succeed against disseminated cancer. Therefore, most valuable information is obtained from studies of vector biodistribution. Owing to the hepatotropism of adenoviral vectors, a particularly important parameter is the tumor/liver ratio. This ratio can be given at the level of gene expression if the amount of transgene expression is measured. To optimize the targeting, however, the levels of viral particles that reach the tumor compared to other organs must be studied. Most of this chapter deals with methods to quantify the virus fate in tumor-bearing animals. We present a radioactive labeling method that can be used to study biodistribution. After a small section dealing with tumor models, we describe methods to quantify different parameters related to adenovirus-mediated tumor targeting.

  14. Exosome mediated communication within the tumor microenvironment.

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    Milane, Lara; Singh, Amit; Mattheolabakis, George; Suresh, Megha; Amiji, Mansoor M

    2015-12-10

    It is clear that exosomes (endosome derived vesicles) serve important roles in cellular communication both locally and distally and that the exosomal process is abnormal in cancer. Cancer cells are not malicious cells; they are cells that represent 'survival of the fittest' at its finest. All of the mutations, abnormalities, and phenomenal adaptations to a hostile microenvironment, such as hypoxia and nutrient depletion, represent the astute ability of cancer cells to adapt to their environment and to intracellular changes to achieve a single goal - survival. The aberrant exosomal process in cancer represents yet another adaptation that promotes survival of cancer. Cancer cells can secrete more exosomes than healthy cells, but more importantly, the content of cancer cells is distinct. An illustrative distinction is that exosomes derived from cancer cells contain more microRNA than healthy cells and unlike exosomes released from healthy cells, this microRNA can be associated with the RNA-induced silencing complex (RISC) which is required for processing mature and biologically active microRNA. Cancer derived exosomes have the ability to transfer metastatic potential to a recipient cell and cancer exosomes function in the physical process of invasion. In this review we conceptualize the aberrant exosomal process (formation, content selection, loading, trafficking, and release) in cancer as being partially attributed to cancer specific differences in the endocytotic process of receptor recycling/degradation and plasma membrane remodeling and the function of the endosome as a signaling entity. We discuss this concept and, to advance comprehension of exosomal function in cancer as mediators of communication, we detail and discuss exosome biology, formation, and communication in health and cancer; exosomal content in cancer; exosomal biomarkers in cancer; exosome mediated communication in cancer metastasis, drug resistance, and interfacing with the immune system; and

  15. The impact of stress on tumor growth: peripheral CRF mediates tumor-promoting effects of stress

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    Stathopoulos Efstathios N

    2010-09-01

    Full Text Available Abstract Introduction Stress has been shown to be a tumor promoting factor. Both clinical and laboratory studies have shown that chronic stress is associated with tumor growth in several types of cancer. Corticotropin Releasing Factor (CRF is the major hypothalamic mediator of stress, but is also expressed in peripheral tissues. Earlier studies have shown that peripheral CRF affects breast cancer cell proliferation and motility. The aim of the present study was to assess the significance of peripheral CRF on tumor growth as a mediator of the response to stress in vivo. Methods For this purpose we used the 4T1 breast cancer cell line in cell culture and in vivo. Cells were treated with CRF in culture and gene specific arrays were performed to identify genes directly affected by CRF and involved in breast cancer cell growth. To assess the impact of peripheral CRF as a stress mediator in tumor growth, Balb/c mice were orthotopically injected with 4T1 cells in the mammary fat pad to induce breast tumors. Mice were subjected to repetitive immobilization stress as a model of chronic stress. To inhibit the action of CRF, the CRF antagonist antalarmin was injected intraperitoneally. Breast tissue samples were histologically analyzed and assessed for neoangiogenesis. Results Array analysis revealed among other genes that CRF induced the expression of SMAD2 and β-catenin, genes involved in breast cancer cell proliferation and cytoskeletal changes associated with metastasis. Cell transfection and luciferase assays confirmed the role of CRF in WNT- β-catenin signaling. CRF induced 4T1 cell proliferation and augmented the TGF-β action on proliferation confirming its impact on TGFβ/SMAD2 signaling. In addition, CRF promoted actin reorganization and cell migration, suggesting a direct tumor-promoting action. Chronic stress augmented tumor growth in 4T1 breast tumor bearing mice and peripheral administration of the CRF antagonist antalarmin suppressed this

  16. Role of adenosine A2b receptor overexpression in tumor progression.

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    Sepúlveda, Cesar; Palomo, Iván; Fuentes, Eduardo

    2016-12-01

    The adenosine A2b receptor is a G-protein coupled receptor. Its activation occurs with high extracellular adenosine concentration, for example in inflammation or hypoxia. These conditions are generated in the tumor environment. Studies show that A2b receptor is overexpressed in various tumor lines and biopsies from patients with different cancers. This suggests that A2b receptor can be used by tumor cells to promote progression. Thus A2b participates in different events, such as angiogenesis and metastasis, besides exerting immunomodulatory effects that protect tumor cells. Therefore, adenosine A2b receptor appears as an interesting therapeutic target for cancer treatment.

  17. Autoradiographic and histopathological studies of boric acid-mediated BNCT in hepatic VX2 tumor-bearing rabbits: Specific boron retention and damage in tumor and tumor vessels.

    Science.gov (United States)

    Yang, C H; Lin, Y T; Hung, Y H; Liao, J W; Peir, J J; Liu, H M; Lin, Y L; Liu, Y M; Chen, Y W; Chuang, K S; Chou, F I

    2015-12-01

    Hepatoma is a malignant tumor that responds poorly to conventional therapies. Boron neutron capture therapy (BNCT) may provide a better way for hepatoma therapy. In this research, (10)B-enriched boric acid (BA, 99% (10)B) was used as the boron drug. A multifocal hepatic VX2 tumor-bearing rabbit model was used to study the mechanisms of BA-mediated BNCT. Autoradiography demonstrated that BA was selectively targeted to tumors and tumor vessels. Histopathological examination revealed the radiation damage to tumor-bearing liver was concentrated in the tumor regions during BNCT treatment. The selective killing of tumor cells and the destruction of the blood vessels in tumor masses may be responsible for the success of BA-mediated BNCT for liver tumors. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Vaccination with EphA2-derived T cell-epitopes promotes immunity against both EphA2-expressing and EphA2-negative tumors

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    Hatano Manabu

    2004-11-01

    Full Text Available Abstract Background A novel tyrosine kinase receptor EphA2 is expressed at high levels in advanced and metastatic cancers. We examined whether vaccinations with synthetic mouse EphA2 (mEphA2-derived peptides that serve as T cell epitopes could induce protective and therapeutic anti-tumor immunity. Methods C57BL/6 mice received subcutaneous (s.c. vaccinations with bone marrow-derived dendritic cells (DCs pulsed with synthetic peptides recognized by CD8+ (mEphA2671–679, mEphA2682–689 and CD4+ (mEphA230–44 T cells. Splenocytes (SPCs were harvested from primed mice to assess the induction of cytotoxic T lymphocyte (CTL responses against syngeneic glioma, sarcoma and melanoma cell lines. The ability of these vaccines to prevent or treat tumor (s.c. injected MCA205 sarcoma or B16 melanoma; i.v. injected B16-BL6 establishment/progression was then assessed. Results Immunization of C57BL/6 mice with mEphA2-derived peptides induced specific CTL responses in SPCs. Vaccination with mEPhA2 peptides, but not control ovalbumin (OVA peptides, prevented the establishment or prevented the growth of EphA2+ or EphA2-negative syngeneic tumors in both s.c. and lung metastasis models. Conclusions These data indicate that mEphA2 can serve as an attractive target against which to direct anti-tumor immunity. The ability of mEphA2 vaccines to impact EphA2-negative tumors such as the B16 melanoma may suggest that such beneficial immunity may be directed against alternative EphA2+ target cells, such as the tumor-associated vascular endothelial cells.

  19. Vaccinia virus-mediated intra-tumoral expression of matrix metalloproteinase 9 enhances oncolysis of PC-3 xenograft tumors

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    Schäfer Simon

    2012-08-01

    Full Text Available Abstract Background Oncolytic viruses, including vaccinia virus (VACV, are a promising alternative to classical mono-cancer treatment methods such as surgery, chemo- or radiotherapy. However, combined therapeutic modalities may be more effective than mono-therapies. In this study, we enhanced the effectiveness of oncolytic virotherapy by matrix metalloproteinase (MMP-9-mediated degradation of proteins of the tumoral extracellular matrix (ECM, leading to increased viral distribution within the tumors. Methods For this study, the oncolytic vaccinia virus GLV-1h255, containing the mmp-9 gene, was constructed and used to treat PC-3 tumor-bearing mice, achieving an intra-tumoral over-expression of MMP-9. The intra-tumoral MMP-9 content was quantified by immunohistochemistry in tumor sections. Therapeutic efficacy of GLV-1h255 was evaluated by monitoring tumor growth kinetics and intra-tumoral virus titers. Microenvironmental changes mediated by the intra-tumoral MMP-9 over-expression were investigated by microscopic quantification of the collagen IV content, the blood vessel density (BVD and the analysis of lymph node metastasis formation. Results GLV-1h255-treatment of PC-3 tumors led to a significant over-expression of intra-tumoral MMP-9, accompanied by a marked decrease in collagen IV content in infected tumor areas, when compared to GLV-1h68-infected tumor areas. This led to considerably elevated virus titers in GLV-1h255 infected tumors, and to enhanced tumor regression. The analysis of the BVD, as well as the lumbar and renal lymph node volumes, revealed lower BVD and significantly smaller lymph nodes in both GLV-1h68- and GLV-1h255- injected mice compared to those injected with PBS, indicating that MMP-9 over-expression does not alter the metastasis-reducing effect of oncolytic VACV. Conclusions Taken together, these results indicate that a GLV-1h255-mediated intra-tumoral over-expression of MMP-9 leads to a degradation of collagen IV

  20. Silencing Receptor EphA2 Enhanced Sensitivity to Lipoplatin™ in Lung Tumor and MPM Cells.

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    Lee, Hung-Yen; Mohammed, Kamal A; Goldberg, Eugene P; Kaye, Frederic; Najmunnisa, Nasreen

    2016-08-08

    Receptor EphA2 is overexpressed in lung cancer and malignant pleural mesothelioma (MPM) which promote tumorogenesis. Lipoplatin™, a new liposomal cisplatin formulation, is used against resistant tumors. Use of cisplatin-based drugs leads to unacceptable toxicities. To improve the effectiveness of Lipoplatin, enhancing the cellular sensitivity of lung tumor and MPM cells is critical. Therefore, we targeted receptor EphA2 by silencing interference RNA (siRNA) and treated tumor cells with Lipoplatin. The combined effects of siRNA-EphA2 and Lipoplatin were determined. We report that silencing EphA2 significantly enhanced the cellular sensitivity of lung tumor and MPM cells to Lipoplatin and maybe a potential therapy for lung cancer.

  1. The tumor microenvironment: An irreplaceable element of tumor budding and epithelial-mesenchymal transition-mediated cancer metastasis.

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    Li, Hui; Xu, Fangying; Li, Si; Zhong, Anjing; Meng, Xianwen; Lai, Maode

    2016-07-03

    Tumor budding occurs at the invasive front of cancer; the tumor cells involved have metastatic and stemness features, indicating a poor prognosis. Tumor budding is partly responsible for cancer metastasis, and its initiation is based on the epithelial-mesenchymal transition (EMT) process. The EMT process involves the conversion of epithelial cells into migratory and invasive cells, and is a profound event in tumorigenesis. The EMT, associated with the formation of cancer stem cells (CSCs) and resistance to therapy, results from a combination of gene mutation, epigenetic regulation, and microenvironmental control. Tumor budding can be taken to represent the EMT in vivo. The EMT process is under the influence of the tumor microenvironment as well as tumor cells themselves. Here, we demonstrate that the tumor microenvironment dominates EMT development and impacts cancer metastasis, as well as promotes CSC formation and mediates drug resistance. In this review, we mainly discuss components of the microenvironment, such as the extracellular matrix (ECM), inflammatory cytokines, metabolic products, and hypoxia, that are involved in and impact on the acquisition of tumor-cell motility and dissemination, the EMT, metastatic tumor-cell formation, tumor budding and CSCs, and cancer metastasis, including subsequent chemo-resistance. From our point of view, the tumor microenvironment now constitutes a promising target for cancer therapy.

  2. Development of drug loaded nanoparticles for tumor targeting. Part 2: Enhancement of tumor penetration through receptor mediated transcytosis in 3D tumor models

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    El-Dakdouki, Mohammad H.; Puré, Ellen; Huang, Xuefei

    2013-04-01

    We report that receptor mediated transcytosis can be utilized to facilitate tumor penetration by drug loaded nanoparticles (NPs). We synthesized hyaluronan (HA) coated silica nanoparticles (SNPs) containing a highly fluorescent core to target CD44 expressed on the cancer cell surface. Although prior studies have primarily focused on CD44 mediated endocytosis to facilitate cellular uptake of HA-NPs by cancer cells, we discovered that, once internalized, the HA-SNPs could be transported out of the cells with their cargo. The exported NPs could be taken up by neighboring cells. This enabled the HA-SNPs to penetrate deeper inside tumors and reach a much greater number of tumor cells in 3D tumor models, presumably through tandem cycles of CD44 mediated endocytosis and exocytosis. When doxorubicin (DOX) was loaded onto the NPs, better penetration of multilayered tumor cells was observed with much improved cytotoxicities against both drug sensitive and drug resistant cancer spheroids compared to the free drug. Thus, targeting receptors such as CD44 that can readily undergo recycling between the cell surface and interior of the cells can become a useful strategy to enhance the tumor penetration potential of NPs and the efficiency of drug delivery through receptor mediated transcytosis.We report that receptor mediated transcytosis can be utilized to facilitate tumor penetration by drug loaded nanoparticles (NPs). We synthesized hyaluronan (HA) coated silica nanoparticles (SNPs) containing a highly fluorescent core to target CD44 expressed on the cancer cell surface. Although prior studies have primarily focused on CD44 mediated endocytosis to facilitate cellular uptake of HA-NPs by cancer cells, we discovered that, once internalized, the HA-SNPs could be transported out of the cells with their cargo. The exported NPs could be taken up by neighboring cells. This enabled the HA-SNPs to penetrate deeper inside tumors and reach a much greater number of tumor cells in 3D tumor

  3. P-selectin-mediated platelet adhesion promotes tumor growth.

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    Qi, Cuiling; Wei, Bo; Zhou, Weijie; Yang, Yang; Li, Bin; Guo, Simei; Li, Jialin; Ye, Jie; Li, Jiangchao; Zhang, Qianqian; Lan, Tian; He, Xiaodong; Cao, Liu; Zhou, Jia; Geng, Jianguo; Wang, Lijing

    2015-03-30

    Blood platelets foster carcinogenesis. We found that platelets are accumulated in human tumors. P-selectin deficiency and soluble P-selectin abolish platelet deposition within tumors, decreasing secretion of vascular endothelial growth factor and angiogenesis, thereby suppressing tumor growth. Binding of the P-selectin cytoplasmic tail to talin1 triggers the talin1 N-terminal head to interact with the β3 cytoplasmic tail. This activates αIIbβ3 and recruits platelets into tumors. Platelet infiltration into solid tumors occurs through a P-selectin-dependent mechanism.

  4. Phagocytes mediate targeting of iron oxide nanoparticles to tumors for cancer therapy.

    Science.gov (United States)

    Toraya-Brown, Seiko; Sheen, Mee Rie; Baird, Jason R; Barry, Stephen; Demidenko, Eugene; Turk, Mary Jo; Hoopes, P Jack; Conejo-Garcia, Jose R; Fiering, Steven

    2013-01-01

    Nanotechnology has great potential to produce novel therapeutic strategies that target malignant cells through the ability of nanoparticles to get access to and be ingested by living cells. However its specificity for accumulation in tumors, which is the key factor that determines its efficacy, has always been a challenge. Here we tested a novel strategy to target and treat ovarian cancer, a representative peritoneal cancer, using iron oxide nanoparticles (IONPs) and an alternating magnetic field (AMF). Peritoneal tumors in general are directly accessible to nanoparticles administered intraperitoneally (IP), as opposed to the more commonly attempted intravenous (IV) administration. In addition, tumor-associated immunosuppressive phagocytes, a predominant cell population in the tumor microenvironment of almost all solid tumors, and cells that are critical for tumor progression, are constantly recruited to the tumor, and therefore could possibly function to bring nanoparticles to tumors. Here we demonstrate that tumor-associated peritoneal phagocytes ingest and carry IONPs specifically to tumors and that these specifically delivered nanoparticles can damage tumor cells after IONP-mediated hyperthermia generated by AMF. This illustrates therapeutic possibilities of intraperitoneal (IP) injection of nanoparticles and subsequent ingestion by tumor-associated phagocytes, to directly impact tumors or stimulate antitumor immune responses. This approach could use IONPs combined with AMF as done here, or other nanoparticles with cytotoxic potential. Overall, the data presented here support IP injection of nanoparticles to utilize peritoneal phagocytes as a delivery vehicle in association with IONP-mediated hyperthermia as therapeutic strategies for ovarian and other peritoneal cancers.

  5. microRNA-mediated regulation of the tumor microenvironment

    Science.gov (United States)

    Chou, Jonathan; Shahi, Payam; Werb, Zena

    2013-01-01

    The tumor microenvironment includes cells such as fibroblasts, immune cells, endothelial cells, as well as extracellular matrix (ECM), proteases, and cytokines. Together, these components participate in a complex crosstalk with neoplastic tumor cells that affects growth, angiogenesis, and metastasis. MicroRNAs (miRNAs) are small, non-coding RNAs involved in post-transcriptional regulation of gene expression and have recently emerged as important players involved in regulating multiple aspects of cancer biology and the tumor microenvironment. Differential miRNA expression in both the epithelial and stromal compartments of tumors compared with normal tissue suggests that miRNAs are important drivers of tumorigenesis and metastasis. This review article summarizes our current understanding of the diverse roles of miRNAs involved in tumor microenvironment regulation and underscores the importance of miRNAs within multiple cell types that contribute to the hallmarks of cancer. PMID:24036551

  6. Cytosolic phospholipaseA2 inhibition with PLA-695 radiosensitizes tumors in lung cancer animal models.

    Science.gov (United States)

    Thotala, Dinesh; Craft, Jeffrey M; Ferraro, Daniel J; Kotipatruni, Rama P; Bhave, Sandeep R; Jaboin, Jerry J; Hallahan, Dennis E

    2013-01-01

    Lung cancer remains the leading cause of cancer deaths in the United States and the rest of the world. The advent of molecularly directed therapies holds promise for improvement in therapeutic efficacy. Cytosolic phospholipase A2 (cPLA2) is associated with tumor progression and radioresistance in mouse tumor models. Utilizing the cPLA2 specific inhibitor PLA-695, we determined if cPLA2 inhibition radiosensitizes non small cell lung cancer (NSCLC) cells and tumors. Treatment with PLA-695 attenuated radiation induced increases of phospho-ERK and phospho-Akt in endothelial cells. NSCLC cells (LLC and A549) co-cultured with endothelial cells (bEND3 and HUVEC) and pre-treated with PLA-695 showed radiosensitization. PLA-695 in combination with irradiation (IR) significantly reduced migration and proliferation in endothelial cells (HUVEC & bEND3) and induced cell death and attenuated invasion by tumor cells (LLC &A549). In a heterotopic tumor model, the combination of PLA-695 and radiation delayed growth in both LLC and A549 tumors. LLC and A549 tumors treated with a combination of PLA-695 and radiation displayed reduced tumor vasculature. In a dorsal skin fold model of LLC tumors, inhibition of cPLA2 in combination with radiation led to enhanced destruction of tumor blood vessels. The anti-angiogenic effects of PLA-695 and its enhancement of the efficacy of radiotherapy in mouse models of NSCLC suggest that clinical trials for its capacity to improve radiotherapy outcomes are warranted.

  7. ONCOLYTIC VIRUS-MEDIATED REVERSAL OF IMPAIRED TUMOR ANTIGEN PRESENTATION

    Directory of Open Access Journals (Sweden)

    Shashi Ashok Gujar

    2014-04-01

    Full Text Available Anti-tumor immunity can eliminate existing cancer cells and also maintain a constant surveillance against possible relapse. Such an antigen-specific adaptive response begins when tumor-specific T cells become activated. T cell activation requires two signals on antigen presenting cells (APCs: antigen presentation through MHC molecules and co-stimulation. In the absence of one or both of these signals, T cells remain inactivated or can even become tolerized. Cancer cells and their associated microenvironment strategically hinder the processing and presentation of tumor antigens and consequently prevent the development of anti-tumor immunity. Many studies, however, demonstrate that interventions that overturn tumor-associated immune evasion mechanisms can establish anti-tumor immune responses of therapeutic potential. One such intervention is oncolytic virus (OV-based anti-cancer therapy. Here we discuss how OV-induced immunological events override tumor-associated antigen presentation impairment and promote appropriate T cell:APC interaction. Detailed understanding of this phenomenon is pivotal for devising the strategies that will enhance the efficacy of OV-based anti-cancer therapy by complementing its inherent oncolytic

  8. Tumor-Mediated Suppression of Dendritic Cell Vaccines

    Science.gov (United States)

    2005-03-01

    migration to DLNs. A B A 1.2- : .0 4000 rmDC 0., 3000 mDC+TGF-p S. . 0.- 2000 S 0.4m S0.2 Hi n 10000 0.0 CCR1 CCR4 CCR5 CCR6 CCR7 SLC MIP-3p Figure 4...containing tumor microenvironment. Mice bearing established mock transfected (4T1-N) or anti-sense TGF-p-expressing (4T1-asT) tumors received i.t...day Figure 9. Treatment of established 4T1 tumors with Smad7-overexpressing DC. Mice bearing established 4T1-N or 4T1-asT primary tumors received

  9. The critical role of the tumor microenvironment in shaping natural killer cell-mediated anti-tumor immunity

    Directory of Open Access Journals (Sweden)

    Joanna eBaginska

    2013-12-01

    Full Text Available Considerable evidence has been gathered over the last 10 years showing that the tumor microenvironment (TME is not simply a passive recipient of immune cells, but an active participant in the establishment of immunosuppressive conditions. It is now well documented that hypoxia, within the TME, affects the functions of immune effectors including natural killer (NK cells by multiple overlapping mechanisms. Indeed, each cell in the TME, irrespective of its transformation status, has the capacity to adapt to the hostile TME and produce immune modulatory signals or mediators affecting the function of immune cells either directly or through the stimulation of other cells present in the tumor site. This observation has led to intense research efforts focused mainly on tumor-derived factors. Notably, it has become increasingly clear that tumor cells secrete a number of environmental factors such as cytokines, growth factors, exosomes, and microRNAs impacting the immune cell response. Moreover, tumor cells in hostile microenvironments may activate their own intrinsic resistance mechanisms, such as autophagy, to escape the effective immune response. Such adaptive mechanisms may also include the ability of tumor cells to modify their metabolism and release several metabolites to impair the function of immune cells. In this review, we summarize the different mechanisms involved in the TME that affect the anti-tumor immune function of NK cells.

  10. Tumor microenvironment-mediated chemoresistance in breast cancer.

    Science.gov (United States)

    Velaei, Kobra; Samadi, Nasser; Barazvan, Balal; Soleimani Rad, Jafar

    2016-12-01

    Therapy resistance or tumor relapse in cancer is common. Tumors develop resistance to chemotherapeutic through a variety of mechanisms, with tumor microenvironment (TM) serving pivotal roles. Using breast cancer as a paradigm, we propose that responses of cancer cells to drugs are not exclusively determined by their intrinsic characteristics but are also controlled by deriving signals from TM. Affected microenvironment by chemotherapy is an avenue to promote phenotype which tends to resist on to be ruined. Therefore, exclusively targeting cancer cells does not demolish tumor recurrence after chemotherapy. Regardless of tumor-microenvironment pathways and their profound influence on the responsiveness of treatment, diversity of molecular properties of breast cancer also behave differently in terms of response to chemotherapy. And also it is assumed that there is cross-talk between phenotypic diversity and TM. Collectively, raising complex signal from TM in chemotherapy condition often encourages cancer cells are not killed but strengthen. Here, we summarized how TM modifies responses to chemotherapy in breast cancer. We also discussed successful treatment strategies have been considered TM in breast cancer treatment. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Mitochondria mediate tumor necrosis factor-alpha/NF-kappaB signaling in skeletal muscle myotubes

    Science.gov (United States)

    Li, Y. P.; Atkins, C. M.; Sweatt, J. D.; Reid, M. B.; Hamilton, S. L. (Principal Investigator)

    1999-01-01

    Tumor necrosis factor-alpha (TNF-alpha) is implicated in muscle atrophy and weakness associated with a variety of chronic diseases. Recently, we reported that TNF-alpha directly induces muscle protein degradation in differentiated skeletal muscle myotubes, where it rapidly activates nuclear factor kappaB (NF-kappaB). We also have found that protein loss induced by TNF-alpha is NF-kappaB dependent. In the present study, we analyzed the signaling pathway by which TNF-alpha activates NF-kappaB in myotubes differentiated from C2C12 and rat primary myoblasts. We found that activation of NF-kappaB by TNF-alpha was blocked by rotenone or amytal, inhibitors of complex I of the mitochondrial respiratory chain. On the other hand, antimycin A, an inhibitor of complex III, enhanced TNF-alpha activation of NK-kappaB. These results suggest a key role of mitochondria-derived reactive oxygen species (ROS) in mediating NF-kappaB activation in muscle. In addition, we found that TNF-alpha stimulated protein kinase C (PKC) activity. However, other signal transduction mediators including ceramide, Ca2+, phospholipase A2 (PLA2), and nitric oxide (NO) do not appear to be involved in the activation of NF-kappaB.

  12. In vivo tumor cell adhesion in the pulmonary microvasculature is exclusively mediated by tumor cell - endothelial cell interaction

    Directory of Open Access Journals (Sweden)

    Mees Soeren T

    2010-04-01

    Full Text Available Abstract Background Metastasis formation is the leading cause of death among colon cancer patients. We established a new in-situ model of in vivo microscopy of the lung to analyse initiating events of metastatic tumor cell adhesion within this typical metastatic target of colon cancer. Methods Anaesthetized CD rats were mechanically ventilated and 106 human HT-29LMM and T84 colon cancer cells were injected intracardially as single cell suspensions. Quantitative in vivo microscopy of the lung was performed in 10 minute intervals for a total of 40 minutes beginning with the time of injection. Results After vehicle treatment of HT-29LMM controls 15.2 ± 5.3; 14.2 ± 7.5; 11.4 ± 5.5; and 15.4 ± 6.5 cells/20 microscopic fields were found adherent within the pulmonary microvasculature in each 10 minute interval. Similar numbers were found after injection of the lung metastasis derived T84 cell line and after treatment of HT-29LMM with unspecific mouse control-IgG. Subsequently, HT-29LMM cells were treated with function blocking antibodies against β1-, β4-, and αv-integrins wich also did not impair tumor cell adhesion in the lung. In contrast, after hydrolization of sialylated glycoproteins on the cells' surface by neuraminidase, we observed impairment of tumor cell adhesion by more than 50% (p Conclusions These results demonstrate that the initial colon cancer cell adhesion in the capillaries of the lung is predominantly mediated by tumor cell - endothelial cell interactions, possibly supported by platelets. In contrast to reports of earlier studies that metastatic tumor cell adhesion occurs through integrin mediated binding of extracellular matrix proteins in liver, in the lung, the continuously lined endothelium appears to be specifically targeted by circulating tumor cells.

  13. Nanoparticle-mediated p53 gene therapy for tumor inhibition

    OpenAIRE

    Sharma, Blanka; Ma, Wenxue; Adjei, Isaac Morris; Panyam, Jayanth; Dimitrijevic, Sanja; Labhasetwar, Vinod

    2011-01-01

    The p53 tumor suppressor gene is mutated in 50% of human cancers, resulting in more aggressive disease with greater resistance to chemotherapy and radiation therapy. Advances in gene therapy technologies offer a promising approach to restoring p53 function. We have developed polymeric nanoparticles (NPs), based on poly (lactic-co-glycolic acid), that provide sustained intracellular delivery of plasmid DNA, resulting in sustained gene expression without vector-associated toxicity. Our previous...

  14. Slit-Robo signaling mediates lymphangiogenesis and promotes tumor lymphatic metastasis.

    Science.gov (United States)

    Yang, Xiao-Mei; Han, Hai-Xiong; Sui, Fei; Dai, Yu-Min; Chen, Ming; Geng, Jian-Guo

    2010-05-28

    The Slit family of guidance cues binds to Roundabout (Robo) receptors to modulate neuronal, leukocytic, and endothelial migration. Slit-Robo signaling had been reported to function as chemoattractive signal for vascular endothelial cells during angiogenesis. In this study, we found that Robo1 was expressed in lymphatic endothelial cells to mediate the migration and tube formation of these cells upon Slit2 stimulation, which were specifically inhibited by the function-blocking antibody R5 to Slit2/Robo1 interaction. To further explore the lymphangiogenic effect and significance mediated by Slit-Robo signaling, we intercrossed Slit2 transgenic mice with a non-metastatic RIP1-Tag2 mouse tumor model, and found that transgenic overexpression of Slit2 significantly enhanced tumor lymphangiogenesis and subsequently promoted mesenteric lymph node metastasis of pancreatic islet tumors. Taken together, our findings reveal that through interacting with Robo1, Slit2 is a novel and potent lymphangiogenic factor and contributes to tumor lymphatic metastasis.

  15. CDK8-Mediated STAT1-S727 Phosphorylation Restrains NK Cell Cytotoxicity and Tumor Surveillance

    Directory of Open Access Journals (Sweden)

    Eva Maria Putz

    2013-08-01

    Full Text Available The transcription factor STAT1 is important in natural killer (NK cells, which provide immediate defense against tumor and virally infected cells. We show that mutation of a single phosphorylation site (Stat1-S727A enhances NK cell cytotoxicity against a range of tumor cells, accompanied by increased expression of perforin and granzyme B. Stat1-S727A mice display significantly delayed disease onset in NK cell-surveilled tumor models including melanoma, leukemia, and metastasizing breast cancer. Constitutive phosphorylation of S727 depends on cyclin-dependent kinase 8 (CDK8. Inhibition of CDK8-mediated STAT1-S727 phosphorylation may thus represent a therapeutic strategy for stimulating NK cell-mediated tumor surveillance.

  16. Integrin-mediated active tumor targeting and tumor microenvironment response dendrimer-gelatin nanoparticles for drug delivery and tumor treatment.

    Science.gov (United States)

    Hu, Guanlian; Zhang, Huiqing; Zhang, Li; Ruan, Shaobo; He, Qin; Gao, Huile

    2015-12-30

    Due to the high morbidity and mortality of cancer, it has become an urgent matter to develop an effective and a safe treatment strategy. Nanoparticles (NP) based drug delivery systems have gained much attention nowadays but they faced a paradoxical issue in delivering drugs into tumors: NP with large size were characterized with weak tumor penetration, meanwhile NP with small size resulted in poor tumor retention. To solve this problem, we proposed a multistage drug delivery system which could intelligently shrink its size from large size to small size in the presence of matrix metalloproteinase-2 (MMP-2) which were highly expressed in tumor tissues, therefore the multistage system could benefit from its large size for better retention effect in tumor and then shrunk to small size to contribute to better penetration efficiency. The multistage drug delivery system, RGD-DOX-DGL-GNP, was constructed by 155.4nm gelatin NP core (the substrate of MMP-2) and surface decorated with doxorubicin (DOX) and RGD peptide conjugated dendritic poly-l-lysine (DGL, 34.3nm in diameter). In vitro, the size of multistage NP could effectively shrink in the presence of MMP-2. Thus, the RGD-DOX-DGL-GNP could penetrate deep into tumor spheroids. In vivo, this multistage drug delivery system showed higher tumor retention and deeper penetration than both DOX-DGL and DOX-GNP. Consequently, RGD-DOX-DGL-GNP successfully combined the advantages of dendrimers and GNP in vivo, resulting in an outstanding anti-tumor effect. In conclusion, the multistage drug delivery system could intelligently shrink from large size to small size in the tumor microenvironment and displayed better retention and penetration efficiency, making it an impressing system for cancer treatment.

  17. A novel, potent, and specific ephrinA1-based cytotoxin against EphA2 receptor expressing tumor cells.

    Science.gov (United States)

    Wykosky, Jill; Gibo, Denise M; Debinski, Waldemar

    2007-12-01

    We have previously shown that the EphA2 receptor tyrosine kinase is overexpressed in glioblastoma multiforme (GBM) and represents a novel, attractive therapeutic target for the treatment of brain tumors. Here, we have developed an EphA2-targeted agent, ephrinA1-PE38QQR, a novel cytotoxin composed of ephrinA1, a ligand for EphA2, and PE38QQR, a mutated form of Pseudomonas aeruginosa exotoxin A. EphrinA1-PE38QQR showed potent and dose-dependent killing of GBM cells overexpressing the EphA2 receptor in cell viability and clonogenic survival assays, with an average IC(50) of approximately 10(-11) mol/L. The conjugate was also highly effective in killing breast and prostate cancer cells overexpressing EphA2. The cytotoxic effect of ephrinA1-PE38QQR was specific, as it was neutralized by an excess of EphA2 ligands. Moreover, normal human endothelial cells and breast cancer cells that do not overexpress EphA2, as well as GBM cells that have down-regulated EphA2, were not susceptible to the cytotoxin. EphrinA1-PE38QQR-mediated cytotoxicity induced caspase-dependent apoptosis, which was, however, not responsible for cell death in response to the conjugate. In addition, the conjugate elicited no changes in the activity of survival pathways such as phosphoinositide 3-kinase, measured by AKT phosphorylation. This is the first attempt to create a cytotoxic therapy using any of the ephrin ligands of either class (A or B) conjugated to a bacterial toxin. EphrinA1-PE38QQR is very potent and specific, produces cell death that is caspase independent, and forms the basis for the further development of clinically applicable EphA2-targeted cytotoxins.

  18. Function of Helper T Cells in the Memory CTL-mediated Anti-tumor Immunity

    Institute of Scientific and Technical Information of China (English)

    高丰光; GermainJ.P.Fernendo; 刘文军

    2004-01-01

    Abstract To investigate the role of CD4+ helper T (Th) cells in the memory CTL-mediated anti-tumor immunity, the RAG-1 gene knock out mice were adoptively transferred with OT-1 cells to generate the memory CTL, the C57B1/6 mice immunized with the epitope peptide of OVA specific Th cells and with different adjuvants were adopfively transferred with these memory-CTLs, and then the animals were challenged with tumor cells EGT. It was found that although the simple immunization of mice with the epitope peptide of the OVA specific Th cells could generate more effect CTL, but this effect was not so strong enough to resist completely the challenges with tumor cells. Nevertheless, the memory CTL-mediated anti-tumor immune effect required the helps of Th1 and Th2 cells. The cross-regulation between Thl and Th2 cells seemed to be beneficial for the host to generate more effector CTL for mounting an efficient anti-tumor response. It concluded that the interaction between Thl and Th2 cells might be more important than the single subset of Th cells in the memory CTL-mediated anti-tumor immune response. More attention should be paid in this regard for the future studies.

  19. Optimizing Salmonella enterica serovar Typhimurium for bacteria-mediated tumor therapy.

    Science.gov (United States)

    Felgner, Sebastian; Kocijancic, Dino; Frahm, Michael; Curtiss, Roy; Erhardt, Marc; Weiss, Siegfried

    2016-01-01

    Bacteria-mediated tumor therapy using Salmonella enterica serovar Typhimurium is a therapeutic option with great potential. Numerous studies explored the potential of Salmonella Typhimurium for therapeutic applications, however reconciling safety with vectorial efficacy remains a major issue. Recently we have described a conditionally attenuated Salmonella vector that is based on genetic lipopolysaccharide modification. This vector combines strong attenuation with appropriate anti-tumor properties by targeting various cancerous tissues in vivo. Therefore, it was promoted as an anti-tumor agent. In this addendum, we summarize these findings and demonstrate additional optimization steps that may further improve the therapeutic efficacy of our vector strain.

  20. Tumor-derived endothelial cells exhibit aberrant Rho-mediated mechanosensing and abnormal angiogenesis in vitro.

    Science.gov (United States)

    Ghosh, Kaustabh; Thodeti, Charles K; Dudley, Andrew C; Mammoto, Akiko; Klagsbrun, Michael; Ingber, Donald E

    2008-08-12

    Tumor blood vessels exhibit abnormal structure and function that cause disturbed blood flow and high interstitial pressure, which impair delivery of anti-cancer agents. Past efforts to normalize the tumor vasculature have focused on inhibition of soluble angiogenic factors, such as VEGF; however, capillary endothelial (CE) cell growth and differentiation during angiogenesis are also influenced by mechanical forces conveyed by the extracellular matrix (ECM). Here, we explored the possibility that tumor CE cells form abnormal vessels because they lose their ability to sense and respond to these physical cues. These studies reveal that, in contrast to normal CE cells, tumor-derived CE cells fail to reorient their actin cytoskeleton when exposed to uniaxial cyclic strain, exhibit distinct shape sensitivity to variations in ECM elasticity, exert greater traction force, and display an enhanced ability to retract flexible ECM substrates and reorganize into tubular networks in vitro. These behaviors correlate with a constitutively high level of baseline activity of the small GTPase Rho and its downstream effector, Rho-associated kinase (ROCK). Moreover, decreasing Rho-mediated tension by using the ROCK inhibitor, Y27632, can reprogram the tumor CE cells so that they normalize their reorientation response to uniaxial cyclic strain and their ability to form tubular networks on ECM gels. Abnormal Rho-mediated sensing of mechanical cues in the tumor microenvironment may therefore contribute to the aberrant behaviors of tumor CE cells that result in the development of structural abnormalities in the cancer microvasculature.

  1. Loss of STAT3 in Lymphoma Relaxes NK Cell-Mediated Tumor Surveillance

    Energy Technology Data Exchange (ETDEWEB)

    Putz, Eva Maria [Institute of Pharmacology and Toxicology, University of Veterinary Medicine, Veterinaerplatz 1, Vienna 1210 (Austria); Hoelzl, Maria Agnes [Institute of Pharmacology, Center for Physiology and Pharmacology, Medical University of Vienna (MUV), Waehringer Strasse 13A, Vienna 1090 (Austria); Baeck, Julia [Institute of Pharmacology and Toxicology, University of Veterinary Medicine, Veterinaerplatz 1, Vienna 1210 (Austria); Bago-Horvath, Zsuzsanna [Institute of Pharmacology and Toxicology, University of Veterinary Medicine, Veterinaerplatz 1, Vienna 1210 (Austria); Clinical Institute of Pathology, Medical University of Vienna (MUV), Waehringer Gürtel 18-20, Vienna 1090 (Austria); Schuster, Christian [Institute of Pharmacology, Center for Physiology and Pharmacology, Medical University of Vienna (MUV), Waehringer Strasse 13A, Vienna 1090 (Austria); Reichholf, Brian [Institute of Pharmacology and Toxicology, University of Veterinary Medicine, Veterinaerplatz 1, Vienna 1210 (Austria); Kern, Daniela; Aberger, Fritz [Department of Molecular Biology, University of Salzburg, Hellbrunnerstrasse 34, Salzburg 5020 (Austria); Sexl, Veronika; Hoelbl-Kovacic, Andrea, E-mail: andrea.hoelbl@vetmeduni.ac.at [Institute of Pharmacology and Toxicology, University of Veterinary Medicine, Veterinaerplatz 1, Vienna 1210 (Austria)

    2014-01-27

    The transcription factors and proto-oncogenes STAT3 and STAT5 are highly activated in hematological malignancies and represent promising therapeutic targets. Whereas the importance of STAT5 as tumor promoter is beyond doubt, the role of STAT3 in hematological cancers is less well understood. Both, enforced as well as attenuated expression of STAT3 were reported in hematopoietic malignancies. Recent evidence implicates STAT3 as key player for tumor immune surveillance as it both mediates the production of and response to inflammatory cytokines. Here we investigated the effects of STAT3 deletion in a BCR/ABL-induced lymphoma model, which is tightly controlled by natural killer (NK) cells in vivo. Upon STAT3 deletion tumor growth is significantly enhanced when compared to STAT3-expressing controls. The increased tumor size upon loss of STAT3 was accompanied by reduced NK cell infiltration and decreased levels of the cytokine IFN-γ and the chemokine RANTES. Upon transplantation into NK cell-deficient mice differences in lymphoma size were abolished indicating that STAT3 expression in the tumor cells controls NK cell-dependent tumor surveillance. Our findings indicate that STAT3 inhibition in lymphoma patients will impair NK cell-mediated tumor surveillance, which needs to be taken into account when testing STAT3 inhibitors in preclinical or clinical trials.

  2. Loss of STAT3 in Lymphoma Relaxes NK Cell-Mediated Tumor Surveillance

    Directory of Open Access Journals (Sweden)

    Eva Maria Putz

    2014-01-01

    Full Text Available The transcription factors and proto-oncogenes STAT3 and STAT5 are highly activated in hematological malignancies and represent promising therapeutic targets. Whereas the importance of STAT5 as tumor promoter is beyond doubt, the role of STAT3 in hematological cancers is less well understood. Both, enforced as well as attenuated expression of STAT3 were reported in hematopoietic malignancies. Recent evidence implicates STAT3 as key player for tumor immune surveillance as it both mediates the production of and response to inflammatory cytokines. Here we investigated the effects of STAT3 deletion in a BCR/ABL-induced lymphoma model, which is tightly controlled by natural killer (NK cells in vivo. Upon STAT3 deletion tumor growth is significantly enhanced when compared to STAT3-expressing controls. The increased tumor size upon loss of STAT3 was accompanied by reduced NK cell infiltration and decreased levels of the cytokine IFN-γ and the chemokine RANTES. Upon transplantation into NK cell-deficient mice differences in lymphoma size were abolished indicating that STAT3 expression in the tumor cells controls NK cell-dependent tumor surveillance. Our findings indicate that STAT3 inhibition in lymphoma patients will impair NK cell-mediated tumor surveillance, which needs to be taken into account when testing STAT3 inhibitors in preclinical or clinical trials.

  3. RNA nanoparticles harboring annexin A2 aptamer can target ovarian cancer for tumor-specific doxorubicin delivery.

    Science.gov (United States)

    Pi, Fengmei; Zhang, Hui; Li, Hui; Thiviyanathan, Varatharasa; Gorenstein, David G; Sood, Anil K; Guo, Peixuan

    2017-04-01

    A novel modified nucleic acid nanoparticle harboring an annexin A2 aptamer for ovarian cancer cell targeting and a GC rich sequence for doxorubicin loading is designed and constructed. The system utilizes a highly stable three-way junction (3WJ) motif from phi29 packaging RNA as a core structure. A phosphorothioate-modified DNA aptamer targeting annexin A2, Endo28, was conjugated to one arm of the 3WJ. The pRNA-3WJ motif retains correct folding of attached aptamer, keeping its functions intact. It is of significant utility for aptamer-mediated targeted delivery. The DNA/RNA hybrid nanoparticles remained intact after systemic injection in mice and strongly bound to tumors with little accumulation in healthy organs 6 h post-injection. The Endo28-3WJ-Sph1/Dox intercalates selectively enhanced toxicity to annexin A2 positive ovarian cancer cells in vitro. The constructed RNA/DNA hybrid nanoparticles can potentially enhance the therapeutic efficiency of doxorubicin at low doses for ovarian cancer treatment through annexin A2 targeted drug delivery. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Cell mediated therapeutics for cancer treatment: Tumor homing cells as therapeutic delivery vehicles

    Science.gov (United States)

    Balivada, Sivasai

    Many cell types were known to have migratory properties towards tumors and different research groups have shown reliable results regarding cells as delivery vehicles of therapeutics for targeted cancer treatment. Present report discusses proof of concept for 1. Cell mediated delivery of Magnetic nanoparticles (MNPs) and targeted Magnetic hyperthermia (MHT) as a cancer treatment by using in vivo mouse cancer models, 2. Cells surface engineering with chimeric proteins for targeted cancer treatment by using in vitro models. 1. Tumor homing cells can carry MNPs specifically to the tumor site and tumor burden will decrease after alternating magnetic field (AMF) exposure. To test this hypothesis, first we loaded Fe/Fe3O4 bi-magnetic NPs into neural progenitor cells (NPCs), which were previously shown to migrate towards melanoma tumors. We observed that NPCs loaded with MNPs travel to subcutaneous melanoma tumors. After alternating magnetic field (AMF) exposure, the targeted delivery of MNPs by the NPCs resulted in a mild decrease in tumor size (Chapter-2). Monocytes/macrophages (Mo/Ma) are known to infiltrate tumor sites, and also have phagocytic activity which can increase their uptake of MNPs. To test Mo/Ma-mediated MHT we transplanted Mo/Ma loaded with MNPs into a mouse model of pancreatic peritoneal carcinomatosis. We observed that MNP-loaded Mo/Ma infiltrated pancreatic tumors and, after AMF treatment, significantly prolonged the lives of mice bearing disseminated intraperitoneal pancreatic tumors (Chapter-3). 2. Targeted cancer treatment could be achieved by engineering tumor homing cell surfaces with tumor proteases cleavable, cancer cell specific recombinant therapeutic proteins. To test this, Urokinase and Calpain (tumor specific proteases) cleavable; prostate cancer cell (CaP) specific (CaP1 targeting peptide); apoptosis inducible (Caspase3 V266ED3)- rCasp3V266ED3 chimeric protein was designed in silico. Hypothesized membrane anchored chimeric protein (rCasp3V

  5. Macrophages Mediate a Switch between Canonical and Non-Canonical Wnt Pathways in Canine Mammary Tumors

    Science.gov (United States)

    Król, Magdalena; Mucha, Joanna; Majchrzak, Kinga; Homa, Agata; Bulkowska, Małgorzata; Majewska, Alicja; Gajewska, Małgorzata; Pietrzak, Marta; Perszko, Mikołaj; Romanowska, Karolina; Pawłowski, Karol; Manuali, Elisabetta; Hellmen, Eva; Motyl, Tomasz

    2014-01-01

    Objective According to the current hypothesis, tumor-associated macrophages (TAMs) are “corrupted” by cancer cells and subsequently facilitate, rather than inhibit, tumor metastasis. Because the molecular mechanisms of cancer cell–TAM interactions are complicated and controversial we aimed to better define this phenomenon. Methods and Results Using microRNA microarrays, Real-time qPCR and Western blot we showed that co-culture of canine mammary tumor cells with TAMs or treatment with macrophage-conditioned medium inhibited the canonical Wnt pathway and activated the non-canonical Wnt pathway in tumor cells. We also showed that co-culture of TAMs with tumor cells increased expression of canonical Wnt inhibitors in TAMs. Subsequently, we demonstrated macrophage-induced invasive growth patterns and epithelial–mesenchymal transition of tumor cells. Validation of these results in canine mammary carcinoma tissues (n = 50) and xenograft tumors indicated the activation of non-canonical and canonical Wnt pathways in metastatic tumors and non-metastatic malignancies, respectively. Activation of non-canonical Wnt pathway correlated with number of TAMs. Conclusions We demonstrated that TAMs mediate a “switch” between canonical and non-canonical Wnt signaling pathways in canine mammary tumors, leading to increased tumor invasion and metastasis. Interestingly, similar changes in neoplastic cells were observed in the presence of macrophage-conditioned medium or live macrophages. These observations indicate that rather than being “corrupted” by cancer cells, TAMs constitutively secrete canonical Wnt inhibitors that decrease tumor proliferation and development, but as a side effect, they induce the non-canonical Wnt pathway, which leads to tumor metastasis. These data challenge the conventional understanding of TAM–cancer cell interactions. PMID:24404146

  6. Targeting CD47-SIRPα interactions for potentiating therapeutic antibody-mediated tumor cell destruction by phagocytes

    NARCIS (Netherlands)

    Zhao, X.W.

    2014-01-01

    The primary aim of the studies described in this thesis was to investigate the role of CD47-SIRPα interactions in therapeutic antibody-dependent tumor cell destruction by human phagocytes and also explore the killing mechanism(s) by which human phagocytes, and in particular human neutrophils, mediat

  7. Monocyte-mediated tumoricidal activity via the tumor necrosis factor-related cytokine, TRAIL.

    Science.gov (United States)

    Griffith, T S; Wiley, S R; Kubin, M Z; Sedger, L M; Maliszewski, C R; Fanger, N A

    1999-04-19

    TRAIL (tumor necrosis factor [TNF]-related apoptosis-inducing ligand) is a molecule that displays potent antitumor activity against selected targets. The results presented here demonstrate that human monocytes rapidly express TRAIL, but not Fas ligand or TNF, after activation with interferon (IFN)-gamma or -alpha and acquire the ability to kill tumor cells. Monocyte-mediated tumor cell apoptosis was TRAIL specific, as it could be inhibited with soluble TRAIL receptor. Moreover, IFN stimulation caused a concomitant loss of TRAIL receptor 2 expression, which coincides with monocyte acquisition of resistance to TRAIL-mediated apoptosis. These results define a novel mechanism of monocyte-induced cell cytotoxicity that requires TRAIL, and suggest that TRAIL is a key effector molecule in antitumor activity in vivo.

  8. CD47-signal regulatory protein-alpha (SIRP alpha) interactions form a barrier for antibody-mediated tumor cell destruction

    NARCIS (Netherlands)

    Zhao, Xi Wen; van Beek, Ellen M.; Schornagel, Karin; Van der Maaden, Hans; Van Houdt, Michel; Otten, Marielle A.; Finetti, Pascal; Van Egmond, Marjolein; Matozaki, Takashi; Kraal, Georg; Birnbaum, Daniel; van Elsas, Andrea; Kuijpers, Taco W.; Bertucci, Francois; van den Berg, Timo K.

    2011-01-01

    Monoclonal antibodies are among the most promising therapeutic agents for treating cancer. Therapeutic cancer antibodies bind to tumor cells, turning them into targets for immune-mediated destruction. We show here that this antibody-mediated killing of tumor cells is limited by a mechanism involving

  9. Tumorer

    DEFF Research Database (Denmark)

    Prause, J.U.; Heegaard, S.

    2005-01-01

    oftalmologi, øjenlågstumorer, conjunctivale tumorer, malignt melanom, retinoblastom, orbitale tumorer......oftalmologi, øjenlågstumorer, conjunctivale tumorer, malignt melanom, retinoblastom, orbitale tumorer...

  10. Intra-arterial adenoviral mediated tumor transfection in a novel model of cancer gene therapy

    Directory of Open Access Journals (Sweden)

    Siemionow Maria

    2006-08-01

    Full Text Available Abstract Background The aim of the present study was to develop and characterize a novel in vivo cancer gene therapy model in which intra-arterial adenoviral gene delivery can be characterized. In this model, the rat cremaster muscle serves as the site for tumor growth and provides convenient and isolated access to the tumor parenchyma with discrete control of arterial and venous access for delivery of agents. Results Utilizing adenovirus encoding the green fluorescent protein we demonstrated broad tumor transfection. We also observed a dose dependant increment in luciferase activity at the tumor site using an adenovirus encoding the luciferase reporter gene. Finally, we tested the intra-arterial adenovirus dwelling time required to achieve optimal tumor transfection and observed a minimum time of 30 minutes. Conclusion We conclude that adenovirus mediated tumor transfection grown in the cremaster muscle of athymic nude rats via an intra-arterial route could be achieved. This model allows definition of the variables that affect intra-arterial tumor transfection. This particular study suggests that allowing a defined intra-tumor dwelling time by controlling the blood flow of the affected organ during vector infusion can optimize intra-arterial adenoviral delivery.

  11. Nanoparticle-Mediated Photothermal Therapy of Brain Tumors

    Science.gov (United States)

    Makkouk, Amani R.; Madsen, Steen J.

    Nanoparticles (10-1,000 nm diameter) have been investigated for use in numerous diagnostic and therapeutic applications. Gold nanoparticles are particularly appealing due to their biological inertness and the ability to conjugate a wide variety of ligands to their surface. Additionally, their optical properties can be tuned through variations of their size, shape, and composition. For example, gold-silica nanoshells, consisting of a spherical dielectric silica core (100-120 nm diameter) surrounded by a 10-20 nm gold shell, have a strong resonant absorption at approximately 800 nm where light has significant penetration in biological tissues. Following light absorption, surface electrons are photoexcited and the resultant heated electron gas is dissipated to the surrounding medium causing thermal damage. The ability of nanoparticles to convert optical energy to thermal energy makes them ideally suited for photothermal therapy (PTT). This review focuses on the utility of gold-silica nanoshells in PTT of brain tumors. PTT has proven effective in a number of in vitro and in vivo studies. Of particular clinical relevance are results demonstrating PTT efficacy in an orthotopic canine model.

  12. Strategies for improving chemotherapeutic delivery to solid tumors mediated by vascular permeability modulation

    Science.gov (United States)

    Roy Chaudhuri, Tista

    An essential mode of distribution of blood-borne chemotherapeutic agents within a solid tumor is via the micro-circulation. Poor tumor perfusion, because of a lack of functional vasculature or a lack of microvessels, as well as low tumor vascular permeability, can prevent adequate deposition of even low molecular-weight agents into the tumor. The modulation of tumor vascular function and density can provides numerous strategies for improving intratumor deposition of chemotherapeutic agents. Here we investigated strategies to improve drug delivery to two tumor types that share in common poor drug delivery, but differ in the underlying cause. First, in an angiogenesis-driven brain tumor model of Glioblastoma, the vascular permeability barrier, along with poorly-functional vasculature, hinders drug delivery. A strategy of nanoparticle-based tumor 'priming' to attack the vascular permeability barrier, employing sterically stabilized liposomal doxorubicin (SSL-DXR), was investigated. Functional and histological evaluation of tumor vasculature revealed that after an initial period of depressed vascular permeability and vascular pruning 3--4 days after SSL-DXR administration, vascular permeability and perfusion were restored and then elevated after 5--7 days. As a result of tumor priming, deposition of subsequently-administered nanoparticles was enhanced, and the efficacy of temozolomide (TMZ), if administered during the window of elevated permeability, was increased. The sequenced regimen resulted in a persistent reduction of the tumor proliferative index and a 40% suppression of tumor volume, compared to animals that received both agents simultaneously. Second, in a hypovascular, pancreatic ductal adenocarcinoma model, disruption of tumor-stromal communication via sonic hedgehog (sHH) signaling pathway inhibition mediated an indirect vascular proliferation and a more than 2-fold increase in intratumor nanoparticle deposition. Enhanced delivery of SSL-DXR in tumors pre

  13. Radio frequency-mediated local thermotherapy for destruction of pancreatic tumors using Ni-Au core-shell nanowires

    Science.gov (United States)

    Hopkins, Xiaoping; Gill, Waqas Amin; Kringel, Rosemarie; Wang, Guankui; Hass, Jamie; Acharya, Suresh; Park, Jungrae; Tak Jeon, In; An, Boo Hyun; Lee, Ji Sung; Ryu, Jong Eun; Hill, Rod; McIlroy, David; Kim, Young Keun; Choi, Daniel S.

    2017-01-01

    We present a novel method of radio frequency (RF)-mediated thermotherapy in tumors by remotely heating nickel (Ni)-gold (Au) core-shell nanowires (CSNWs). Ectopic pancreatic tumors were developed in nude mice to evaluate the thermotherapeutic effects on tumor progression. Tumor ablation was produced by RF-mediated thermotherapy via activation of the paramagnetic properties of the Ni-Au CSNWs. Histopathology demonstrated that heat generated by RF irradiation caused significant cellular death with pyknotic nuclei and nuclear fragmentation dispersed throughout the tumors. These preliminary results suggest that thermotherapy ablation induced via RF activation of nanowires provides a potential alternative therapy for cancer treatment.

  14. Fasting-Mimicking Diet Reduces HO-1 to Promote T Cell-Mediated Tumor Cytotoxicity.

    Science.gov (United States)

    Di Biase, Stefano; Lee, Changhan; Brandhorst, Sebastian; Manes, Brianna; Buono, Roberta; Cheng, Chia-Wei; Cacciottolo, Mafalda; Martin-Montalvo, Alejandro; de Cabo, Rafael; Wei, Min; Morgan, Todd E; Longo, Valter D

    2016-07-11

    Immune-based interventions are promising strategies to achieve long-term cancer-free survival. Fasting was previously shown to differentially sensitize tumors to chemotherapy while protecting normal cells, including hematopoietic stem and immune cells, from its toxic side effects. Here, we show that the combination of chemotherapy and a fasting-mimicking diet (FMD) increases the levels of bone marrow common lymphoid progenitor cells and cytotoxic CD8(+) tumor-infiltrating lymphocytes (TILs), leading to a major delay in breast cancer and melanoma progression. In breast tumors, this effect is partially mediated by the downregulation of the stress-responsive enzyme heme oxygenase-1 (HO-1). These data indicate that FMD cycles combined with chemotherapy can enhance T cell-dependent targeted killing of cancer cells both by stimulating the hematopoietic system and by enhancing CD8(+)-dependent tumor cytotoxicity.

  15. Combining cytotoxic and immune-mediated gene therapy to treat brain tumors.

    Science.gov (United States)

    Curtin, James F; King, Gwendalyn D; Candolfi, Marianela; Greeno, Remy B; Kroeger, Kurt M; Lowenstein, Pedro R; Castro, Maria G

    2005-01-01

    Glioblastoma (GBM) is a type of intracranial brain tumor, for which there is no cure. In spite of advances in surgery, chemotherapy and radiotherapy, patients die within a year of diagnosis. Therefore, there is a critical need to develop novel therapeutic approaches for this disease. Gene therapy, which is the use of genes or other nucleic acids as drugs, is a powerful new treatment strategy which can be developed to treat GBM. Several treatment modalities are amenable for gene therapy implementation, e.g. conditional cytotoxic approaches, targeted delivery of toxins into the tumor mass, immune stimulatory strategies, and these will all be the focus of this review. Both conditional cytotoxicity and targeted toxin mediated tumor death, are aimed at eliminating an established tumor mass and preventing further growth. Tumors employ several defensive strategies that suppress and inhibit anti-tumor immune responses. A better understanding of the mechanisms involved in eliciting anti-tumor immune responses has identified promising targets for immunotherapy. Immunotherapy is designed to aid the immune system to recognize and destroy tumor cells in order to eliminate the tumor burden. Also, immune-therapeutic strategies have the added advantage that an activated immune system has the capability of recognizing tumor cells at distant sites from the primary tumor, therefore targeting metastasis distant from the primary tumor locale. Pre-clinical models and clinical trials have demonstrated that in spite of their location within the central nervous system (CNS), a tissue described as 'immune privileged', brain tumors can be effectively targeted by the activated immune system following various immunotherapeutic strategies. This review will highlight recent advances in brain tumor immunotherapy, with particular emphasis on advances made using gene therapy strategies, as well as reviewing other novel therapies that can be used in combination with immunotherapy. Another important

  16. Macrophage PPARγ inhibits Gpr132 to mediate the anti-tumor effects of rosiglitazone

    Science.gov (United States)

    Cheng, Wing Yin; Huynh, HoangDinh; Chen, Peiwen; Peña-Llopis, Samuel; Wan, Yihong

    2016-01-01

    Tumor-associated macrophage (TAM) significantly contributes to cancer progression. Human cancer is enhanced by PPARγ loss-of-function mutations, but inhibited by PPARγ agonists such as TZD diabetes drugs including rosiglitazone. However, it remains enigmatic whether and how macrophage contributes to PPARγ tumor-suppressive functions. Here we report that macrophage PPARγ deletion in mice not only exacerbates mammary tumor development but also impairs the anti-tumor effects of rosiglitazone. Mechanistically, we identify Gpr132 as a novel direct PPARγ target in macrophage whose expression is enhanced by PPARγ loss but repressed by PPARγ activation. Functionally, macrophage Gpr132 is pro-inflammatory and pro-tumor. Genetic Gpr132 deletion not only retards inflammation and cancer growth but also abrogates the anti-tumor effects of PPARγ and rosiglitazone. Pharmacological Gpr132 inhibition significantly impedes mammary tumor malignancy. These findings uncover macrophage PPARγ and Gpr132 as critical TAM modulators, new cancer therapeutic targets, and essential mediators of TZD anti-cancer effects. DOI: http://dx.doi.org/10.7554/eLife.18501.001

  17. Phenobarbital-mediated tumor promotion in transgenic mice with humanized CAR and PXR.

    Science.gov (United States)

    Braeuning, Albert; Gavrilov, Alina; Brown, Susan; Wolf, C Roland; Henderson, Colin J; Schwarz, Michael

    2014-08-01

    The nuclear receptors CAR (constitutive androstane receptor) and possibly PXR (pregnane X receptor) mediate the hepatic effects of phenobarbital (PB) and similar-acting compounds. Although PB is a potent nongenotoxic tumor promoter in rodent liver, epidemiological data from epilepsy patients treated with phenobarbital do not show a specific role of PB in human liver cancer risk. That points to species differences in the susceptibility to tumor promotion by PB, which might be attributed to divergent functions of the PB receptors CAR and PXR in mice and humans. In the present study, male transgenic mice expressing human CAR and PXR were used to detect possible differences between wild-type (WT) and humanized mice in their response to CAR activation in a tumor initiation/promotion experiment with a single injection of the tumor initiator N-nitrosodiethylamine preceding chronic PB treatment for 10 months. Analysis of liver tumor burden revealed that PB strongly promoted the outgrowth of hepatocellular adenoma driven by activated β-catenin in WT mice, whereas the tumor-promoting effect of PB was much less pronounced in the humanized group. In conclusion, the present findings demonstrate that human CAR and PXR support tumor promotion by PB in mouse liver, but to a significantly lesser extent than the WT murine receptors. © The Author 2014. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  18. Dosimetry study of PHOTOFRIN-mediated photodynamic therapy in a mouse tumor model

    Science.gov (United States)

    Qiu, Haixia; Kim, Michele M.; Penjweini, Rozhin; Zhu, Timothy C.

    2016-03-01

    It is well known in photodynamic therapy (PDT) that there is a large variability between PDT light dose and therapeutic outcomes. An explicit dosimetry model using apparent reacted 1O2 concentration [1O2]rx has been developed as a PDT dosimetric quantity to improve the accuracy of the predicted ability of therapeutic efficacy. In this study, this explicit macroscopic singlet oxygen model was adopted to establish the correlation between calculated reacted [1O2]rx and the tumor growth using Photofrin-mediated PDT in a mouse tumor model. Mice with radiation-induced fibrosarcoma (RIF) tumors were injected with Photofrin at a dose of 5 mg/kg. PDT was performed 24h later with different fluence rates (50, 75 and 150 mW/cm2) and different fluences (50 and 135 J/cm2) using a collimated light applicator coupled to a 630nm laser. The tumor volume was monitored daily after PDT and correlated with the total light fluence and [1O2]rx. Photophysical parameters as well as the singlet oxygen threshold dose for this sensitizer and the RIF tumor model were determined previously. The result showed that tumor growth rate varied greatly with light fluence for different fluence rates while [1O2]rx had a good correlation with the PDT-induced tumor growth rate. This preliminary study indicated that [1O2]rx could serve as a better dosimetric predictor for predicting PDT outcome than PDT light dose.

  19. C2-streptavidin mediates the delivery of biotin-conjugated tumor suppressor protein p53 into tumor cells.

    Science.gov (United States)

    Fahrer, Jörg; Schweitzer, Brigitte; Fiedler, Katja; Langer, Torben; Gierschik, Peter; Barth, Holger

    2013-04-17

    We have previously generated a recombinant C2-streptavidin fusion protein for the delivery of biotin-labeled molecules of low molecular weight into the cytosol of mammalian cells. A nontoxic moiety of Clostridium botulinum C2 toxin mediates the cellular uptake, whereas the streptavidin unit serves as a binding platform for biotin-labeled cargo molecules. In the present study, we used the C2-streptavidin transporter to introduce biotin-conjugated p53 protein into various mammalian cell lines. The p53 tumor suppressor protein is inactivated in many human cancers by multiple mechanisms and therefore the restoration of its activity in tumor cells is of great therapeutic interest. Recombinant p53 was expressed in insect cells and biotin-labeled. Biotin-p53 retained its specific high-affinity DNA-binding as revealed by gel-shift analysis. Successful conjugation of biotin-p53 to the C2-streptavidin transporter was monitored by an overlay blot technique and confirmed by real-time surface plasmon resonance, providing a KD-value in the low nM range. C2-streptavidin significantly enhanced the uptake of biotin-p53 into African Green Monkey (Vero) epithelial cells as shown by flow cytometry. Using cell fractionation, the cytosolic translocation of biotin-p53 was detected in Vero cells as well as in HeLa cervix carcinoma cells. In line with this finding, confocal microscopy displayed cytoplasmic staining of biotin-p53 in HeLa and HL60 leukemia cells. Internalized biotin-p53 partially colocalized with early endosomes, as confirmed by confocal microscopy. In conclusion, our results demonstrate the successful conjugation of biotin-p53 to C2-streptavidin and its subsequent receptor-mediated endocytosis into different human tumor cell lines.

  20. Relaxin treatment of solid tumors: effects on electric field-mediated gene delivery.

    Science.gov (United States)

    Henshaw, Joshua; Mossop, Brian; Yuan, Fan

    2008-08-01

    Pulsed electric fields have been shown to enhance interstitial transport of plasmid DNA (pDNA) in solid tumors in vivo. However, the extent of enhancement is still limited partly due to the collagen component in extracellular matrix. To this end, effects of collagen remodeling on interstitial electrophoresis were investigated by pretreatment of tumor-bearing mice with a recombinant human relaxin (rh-Rlx). In the study, two tumor lines (4T1 and B16.F10) were examined and implanted s.c. to establish two murine models: dorsal skin-fold chamber (DSC) and hind leg. Effects of rh-Rlx on pDNA electrophoresis were measured either directly in the DSC model or indirectly in the hind leg model via reporter gene expression. It was observed that rh-Rlx treatment reduced collagen levels in the hind leg tumors but not in the DSC tumors. The observation correlated with the results from electromobility experiments, where rh-Rlx treatment enhanced transgene expression in 4T1 hind leg tumors but did not increase the electromobility of pDNA in the DSC tumors. In addition, it was observed that pDNA binding to collagen could block its diffusion in collagen gel in vitro. These observations showed that effects of rh-Rlx on the collagen content depended on microenvironment in solid tumors and that rh-Rlx treatment would enhance electric field-mediated gene delivery only if it could effectively reduce the collagen content in collagen-rich tumors.

  1. Computational modeling identifies key gene regulatory interactions underlying phenobarbital-mediated tumor promotion

    Science.gov (United States)

    Luisier, Raphaëlle; Unterberger, Elif B.; Goodman, Jay I.; Schwarz, Michael; Moggs, Jonathan; Terranova, Rémi; van Nimwegen, Erik

    2014-01-01

    Gene regulatory interactions underlying the early stages of non-genotoxic carcinogenesis are poorly understood. Here, we have identified key candidate regulators of phenobarbital (PB)-mediated mouse liver tumorigenesis, a well-characterized model of non-genotoxic carcinogenesis, by applying a new computational modeling approach to a comprehensive collection of in vivo gene expression studies. We have combined our previously developed motif activity response analysis (MARA), which models gene expression patterns in terms of computationally predicted transcription factor binding sites with singular value decomposition (SVD) of the inferred motif activities, to disentangle the roles that different transcriptional regulators play in specific biological pathways of tumor promotion. Furthermore, transgenic mouse models enabled us to identify which of these regulatory activities was downstream of constitutive androstane receptor and β-catenin signaling, both crucial components of PB-mediated liver tumorigenesis. We propose novel roles for E2F and ZFP161 in PB-mediated hepatocyte proliferation and suggest that PB-mediated suppression of ESR1 activity contributes to the development of a tumor-prone environment. Our study shows that combining MARA with SVD allows for automated identification of independent transcription regulatory programs within a complex in vivo tissue environment and provides novel mechanistic insights into PB-mediated hepatocarcinogenesis. PMID:24464994

  2. Lumican reduces tumor growth via induction of fas-mediated endothelial cell apoptosis.

    Science.gov (United States)

    Williams, Kent E; Fulford, Logan A; Albig, Allan R

    2010-11-18

    Matrikines are important components of tumor microenvironments that integrate communication between extracellular matricies and membrane-bound receptors thereby regulating cellular behaviors. One such matrikine that is differentially expressed in cancer microenvironments is the extracellular matrix protein lumican; however its precise role in cancer remains ambiguous. To study the effects of lumican on cancer cells, we created lumican-overexpressing cell lines from murine fibrosarcoma (MCA102) and pancreatic adenocarcinoma (Pan02) cells. Lumican overexpression in Pan02 cells increased invasiveness, decreased soft agar colony size, and increased proliferation. Conversely in MCA102 cells, lumican decreased invasiveness, increased soft agar colony size, but did not influence proliferation. In contrast to these pleiotropic in vitro results, lumican overexpression within the in vivo tumor microenvironment produced uniformly smaller tumors. Importantly, reduced tumor size was correlated with reduced vascular density. Consistent with lumican's proposed anti-angiogenic activity, lumican increased endothelial cell apoptosis. Importantly, lumican was previously shown to influence Fas expression and our results show that lumican enhanced Fas mediated endothelial cell apoptosis although we were unable to detect any difference in Fas or Fas ligand expression between lumican-overexpressing and control cells. Interestingly, lumican had no effect on MCA102 apoptosis, suggesting that the observed reduction in tumor size is specifically due to endothelial cell apoptosis rather than a direct effect on the cancerous cells themselves. Therefore, this study is the first to demonstrate a causal relationship between tumor reduction and lumican's effect on angiogenesis as opposed to an effect on the cancerous cells themselves.

  3. Paracrine Apoptotic Effect of p53 Mediated by Tumor Suppressor Par-4

    Directory of Open Access Journals (Sweden)

    Ravshan Burikhanov

    2014-01-01

    Full Text Available The guardian of the genome, p53, is often mutated in cancer and may contribute to therapeutic resistance. Given that p53 is intact and functional in normal tissues, we harnessed its potential to inhibit the growth of p53-deficient cancer cells. Specific activation of p53 in normal fibroblasts selectively induced apoptosis in p53-deficient cancer cells. This paracrine effect was mediated by p53-dependent secretion of the tumor suppressor Par-4. Accordingly, the activation of p53 in normal mice, but not p53−/− or Par-4−/− mice, caused systemic elevation of Par-4, which induced apoptosis of p53-deficient tumor cells. Mechanistically, p53 induced Par-4 secretion by suppressing the expression of its binding partner, UACA, which sequesters Par-4. Thus, normal cells can be empowered by p53 activation to induce Par-4 secretion for the inhibition of therapy-resistant tumors.

  4. Macrophage-mediated tumor cytotoxicity: role of macrophage surface sialic acid.

    Science.gov (United States)

    Cameron, D J

    1983-02-01

    Cell surface sialic acid levels were compared for monocytes and macrophages obtained from normal volunteers and breast cancer patients. Equal quantities of sialic acid were found on the monocytes obtained from normal volunteers and breast cancer patients. Approximately 60% more cell surface sialic acid was found on the macrophages from breast cancer patients than was found on the macrophages from normal volunteers. In order to determine whether cell surface sialic acid had any effect on macrophage-mediated cytotoxicity, macrophages were pretreated with neuraminidase (NANAse) prior to co-cultivation with tumor cells. The normal macrophages, after neuraminidase treatment, no longer retained their ability to kill tumor cells. However, when macrophages from breast cancer patients were treated with NANAse, no difference was observed in the ability of untreated and NANAse treated macrophages to kill tumor cells.

  5. Translationally Controlled Tumor Protein Stimulates Dopamine Release from PC12 Cells via Ca2+-Independent Phospholipase A2 Pathways

    Directory of Open Access Journals (Sweden)

    Jihui Seo

    2016-10-01

    Full Text Available The translationally controlled tumor protein (TCTP, initially identified as a tumor- and growth-related protein, is also known as a histamine-releasing factor (HRF. TCTP is widely distributed in the neuronal systems, but its function is largely uncharacterized. Here, we report a novel function of TCTP in the neurotransmitter release from a neurosecretory, pheochromocytoma (PC12 cells. Treatment with recombinant TCTP (rTCTP enhanced both basal and depolarization (50 mM KCl-evoked [3H]dopamine release in concentration- and time-dependent manners. Interestingly, even though rTCTP induced the increase in intracellular calcium levels ([Ca2+]i, the rTCTP-driven effect on dopamine release was mediated by a Ca2+-independent pathway, as evidenced by the fact that Ca2+-modulating agents such as Ca2+ chelators and a voltage-gated L-type Ca2+-channel blocker did not produce any changes in rTCTP-evoked dopamine release. In a study to investigate the involvement of phospholipase A2 (PLA2 in rTCTP-induced dopamine release, the inhibitor for Ca2+-independent PLA2 (iPLA2 produced a significant inhibitory effect on rTCTP-induced dopamine release, whereas this release was not significantly inhibited by Ca2+-dependent cytosolic PLA2 (cPLA2 and secretory PLA2 (sPLA2 inhibitors. We found that rTCTP-induced dopamine release from neuronal PC12 cells was modulated by a Ca2+-independent mechanism that involved PLA2 in the process, suggesting the regulatory role of TCTP in the neuronal functions.

  6. Type I Interferons Exert Anti-tumor Effect via Reversing Immunosuppression Mediated by Mesenchymal Stromal Cells

    Science.gov (United States)

    Shou, Peishun; Chen, Qing; Jiang, Jingting; Xu, Chunliang; Zhang, Jimin; Zheng, Chunxing; Jiang, Menghui; Velletri, Tania; Cao, Wei; Huang, Yin; Yang, Qian; Han, Xiaoyan; Zhang, Liying; Wei, Lixin; Rabson, Arnold B.; Chin, Y. Eugene; Wang, Ying; Shi, Yufang

    2016-01-01

    Mesenchymal stromal cells (MSCs) are strongly immunosuppressive via producing nitric oxide (NO) and known to migrate into tumor sites to promote tumor growth, but the underlying mechanisms remain largely elusive. Here, we found that IFNα-secreting MSCs showed more dramatic inhibition effect on tumor progression than that of IFNα alone. Interestingly, IFNα-primed MSCs could also effectively suppress tumor growth. Mechanistically, we demonstrated that both IFNα and IFNβ (type I IFNs) reversed the immunosuppressive effect of MSCs on splenocyte proliferation. This effect of type I IFNs was exerted through inhibiting iNOS (inducible nitric oxide synthase) expression in IFNγ and TNFα-stimulated MSCs. Notably, only NO production was inhibited by IFNα; production of other cytokines or chemokines tested was not suppressed. Furthermore, IFNα promoted the switch from Stat1 homodimers to Stat1-Stat2 heterodimers. Studies using the luciferase reporter system and chromatin immunoprecipitation assay revealed that IFNα suppressed iNOS transcription through inhibiting the binding of Stat1 to iNOS promoter. Therefore, the synergistic anti-tumor effects of type I IFNs and MSCs were achieved by inhibiting NO production. This study provides essential information for understanding the mechanisms of MSC-mediated immunosuppression and for the development of better clinical strategies using IFNs and MSCs for cancer immunotherapy. PMID:27109100

  7. CBP-mediated FOXO-1 acetylation inhibits pancreatic tumor growth by targeting SirT.

    Science.gov (United States)

    Pramanik, Kartick C; Fofaria, Neel M; Gupta, Parul; Srivastava, Sanjay K

    2014-03-01

    Here, we investigated the potential mechanism of capsaicin-mediated apoptosis in pancreatic cancer cells. Capsaicin treatment phosphorylated c-jun-NH2-kinase (JNK); forkhead box transcription factor, class O (FOXO1); and BIM in BxPC-3, AsPC-1, and L3.6PL cells. The expression of BIM increased in response to capsaicin treatment. Capsaicin treatment caused cleavage of caspase-3 and PARP, indicating apoptosis. Antioxidants tiron and PEG-catalase blocked capsaicin-mediated JNK/FOXO/BIM activation and protected the cells from apoptosis. Furthermore, capsaicin treatment caused a steady increase in the nuclear expression of FOXO-1, leading to increased DNA binding. Capsaicin-mediated expression of BIM was found to be directly dependent on the acetylation of FOXO-1. The expression of CREB-binding protein (CBP) was increased, whereas SirT-1 was reduced by capsaicin treatment. Using acetylation mimic or defective mutants, our result demonstrated that phosphorylation of FOXO-1 was mediated through acetylation by capsaicin treatment. JNK inhibitor attenuated the phosphorylation of FOXO-1, activation of BIM, and abrogated capsaicin-induced apoptosis. Moreover, silencing FOXO1 by siRNA blocked capsaicin-mediated activation of BIM and apoptosis, whereas overexpression of FOXO-1 augmented its effects. Silencing Bim drastically reduced capsaicin-mediated cleavage of caspase-3 and PARP, indicating the role of BIM in apoptosis. Oral administration of 5 mg/kg capsaicin substantially suppressed the growth of BxPC-3 tumor xenografts in athymic nude mice. Tumors from capsaicin-treated mice showed an increase in the phosphorylation of JNK, FOXO-1, BIM, and levels of CBP, cleavage of caspase-3, PARP, and decreased SirT-1 expression. Taken together, our results suggest that capsaicin activated JNK and FOXO-1, leading to the acetylation of FOXO-1 through CBP and SirT-1. Acetylated FOXO1 induced apoptosis in pancreatic cancer cells through BIM activation.

  8. GLI1 is a central mediator of EWS/FLI1 signaling in Ewing tumors.

    Directory of Open Access Journals (Sweden)

    Jay Joo

    Full Text Available The Ewing Sarcoma Family Tumors (ESFT consist of the classical pathologic entities of Ewing Sarcoma and peripheral Primitive Neuroectodermal Tumor. Occurring largely in the childhood through young adult years, these tumors have an unsurpassed propensity for metastasis and have no defined cell of origin. The biology of these aggressive malignancies centers around EWS/FLI1 and related EWS/ETS chimeric transcription factors, which are largely limited to this tumor class. Much progress has been made in the identification of a network of loci whose expression is modulated by EWS/FLI1 and its congeners. To date, little progress has been made in reconstructing the sequence of direct and indirect events that produce this network of modulated loci. The recent identification of GLI1 as an upregulated target of EWS/ETS transcription factors suggests a target which may be a more central mediator in the ESFT signaling network. In this paper, we further define the relationship of EWS/FLI1 expression and GLI1 upregulation in ESFT. This relationship is supported with data from primary tumor specimens. It is consistently observed across multiple ESFT cell lines and with multiple means of EWS/FLI1 inhibition. GLI1 inhibition affects tumor cell line phenotype whether shRNA or endogenous or pharmacologic inhibitors are employed. As is seen in model transformation systems, GLI1 upregulation by EWS/FLI1 appears to be independent of Hedgehog stimulation. Consistent with a more central role in ESFT pathogenesis, several known EWS/FLI1 targets appear to be targeted through GLI1. These findings further establish a central role for GLI1 in the pathogenesis of Ewing Tumors.

  9. HMGB1 mediates endogenous TLR2 activation and brain tumor regression.

    Directory of Open Access Journals (Sweden)

    James F Curtin

    2009-01-01

    Full Text Available BACKGROUND: Glioblastoma multiforme (GBM is the most aggressive primary brain tumor that carries a 5-y survival rate of 5%. Attempts at eliciting a clinically relevant anti-GBM immune response in brain tumor patients have met with limited success, which is due to brain immune privilege, tumor immune evasion, and a paucity of dendritic cells (DCs within the central nervous system. Herein we uncovered a novel pathway for the activation of an effective anti-GBM immune response mediated by high-mobility-group box 1 (HMGB1, an alarmin protein released from dying tumor cells, which acts as an endogenous ligand for Toll-like receptor 2 (TLR2 signaling on bone marrow-derived GBM-infiltrating DCs. METHODS AND FINDINGS: Using a combined immunotherapy/conditional cytotoxic approach that utilizes adenoviral vectors (Ad expressing Fms-like tyrosine kinase 3 ligand (Flt3L and thymidine kinase (TK delivered into the tumor mass, we demonstrated that CD4(+ and CD8(+ T cells were required for tumor regression and immunological memory. Increased numbers of bone marrow-derived, tumor-infiltrating myeloid DCs (mDCs were observed in response to the therapy. Infiltration of mDCs into the GBM, clonal expansion of antitumor T cells, and induction of an effective anti-GBM immune response were TLR2 dependent. We then proceeded to identify the endogenous ligand responsible for TLR2 signaling on tumor-infiltrating mDCs. We demonstrated that HMGB1 was released from dying tumor cells, in response to Ad-TK (+ gancyclovir [GCV] treatment. Increased levels of HMGB1 were also detected in the serum of tumor-bearing Ad-Flt3L/Ad-TK (+GCV-treated mice. Specific activation of TLR2 signaling was induced by supernatants from Ad-TK (+GCV-treated GBM cells; this activation was blocked by glycyrrhizin (a specific HMGB1 inhibitor or with antibodies to HMGB1. HMGB1 was also released from melanoma, small cell lung carcinoma, and glioma cells treated with radiation or temozolomide

  10. A Novel Antagonist of the Immune Checkpoint Protein Adenosine A2a Receptor Restores Tumor-Infiltrating Lymphocyte Activity in the Context of the Tumor Microenvironment

    Directory of Open Access Journals (Sweden)

    Melanie Mediavilla-Varela

    2017-07-01

    Full Text Available BACKGROUND: Therapeutic strategies targeting immune checkpoint proteins have led to significant responses in patients with various tumor types. The success of these studies has led to the development of various antibodies/inhibitors for the different checkpoint proteins involved in immune evasion of the tumor. Adenosine present in high concentrations in the tumor microenvironment activates the immune checkpoint adenosine A2a receptor (A2aR, leading to the suppression of antitumor responses. Inhibition of this checkpoint has the potential to enhance antitumor T-cell responsiveness. METHODS: We developed a novel A2aR antagonist (PBF-509 and tested its antitumor response in vitro, in a mouse model, and in non-small cell lung cancer patient samples. RESULTS: Our studies showed that PBF-509 is highly specific to the A2aR as well as inhibitory of A2aR function in an in vitro model. In a mouse model, we found that lung metastasis was decreased after treatment with PBF-509 compared with its control. Furthermore, freshly resected tumor-infiltrating lymphocytes from lung cancer patients showed increased A2aR expression in CD4+ cells and variable expression in CD8+ cells. Ex vivo studies showed an increased responsiveness of human tumor-infiltrating lymphocytes when PBF-509 was combined with anti-PD-1 or anti-PD-L1. CONCLUSIONS: Our studies demonstrate that inhibition of the A2aR using the novel inhibitor PBF-509 could lead to novel immunotherapeutic strategies in non-small cell lung cancer.

  11. A HLA-A2 restricted human CTL line recognizes a novel tumor cell expressed p53 epitope

    DEFF Research Database (Denmark)

    Würtzen, Peter A; Claesson, Mogens H

    2002-01-01

    line, indicating that this novel p53 peptide epitope is endogenously processed and presented by the HLA-A2 molecules of the tumor cells. In conclusion, CTL reactivity towards a wild-type p53 peptide was revealed through induction with DC pulsed with a pool of HLA-A2 binding p53 peptides. In addition...

  12. The potential role of COX-2 in cancer stem cell-mediated canine mammary tumor initiation: an immunohistochemical study

    OpenAIRE

    Huang, Jian; Zhang, Di; Xie, Fuqiang; LIN, Degui

    2015-01-01

    Increasing evidence suggests that cancer stem cells (CSCs) are responsible for tumor initiation and maintenance. Additionally, it is becoming apparent that cyclooxygenase (COX) signaling is associated with canine mammary tumor development. The goals of the present study were to investigate COX-2 expression patterns and their effect on CSC-mediated tumor initiation in primary canine mammary tissues and tumorsphere models using immunohistochemistry. Patterns of COX-2, CD44, octamer-binding tran...

  13. Acetylation Is Crucial for p53-Mediated Ferroptosis and Tumor Suppression

    Directory of Open Access Journals (Sweden)

    Shang-Jui Wang

    2016-10-01

    Full Text Available Although previous studies indicate that loss of p53-mediated cell cycle arrest, apoptosis, and senescence does not completely abrogate its tumor suppression function, it is unclear how the remaining activities of p53 are regulated. Here, we have identified an acetylation site at lysine K98 in mouse p53 (or K101 for human p53. Whereas the loss of K98 acetylation (p53K98R alone has very modest effects on p53-mediated transactivation, simultaneous mutations at all four acetylation sites (p534KR: K98R+ 3KR[K117R+K161R+K162R] completely abolish its ability to regulate metabolic targets, such as TIGAR and SLC7A11. Notably, in contrast to p533KR, p534KR is severely defective in suppressing tumor growth in mouse xenograft models. Moreover, p534KR is still capable of inducing the p53-Mdm2 feedback loop, but p53-dependent ferroptotic responses are markedly abrogated. Together, these data indicate the critical role of p53 acetylation in ferroptotic responses and its remaining tumor suppression activity.

  14. Lymphoid tissue phospholipase A2 group IID resolves contact hypersensitivity by driving antiinflammatory lipid mediators

    Science.gov (United States)

    Miki, Yoshimi; Yamamoto, Kei; Taketomi, Yoshitaka; Sato, Hiroyasu; Shimo, Kanako; Kobayashi, Tetsuyuki; Ishikawa, Yukio; Ishii, Toshiharu; Nakanishi, Hiroki; Ikeda, Kazutaka; Taguchi, Ryo; Kabashima, Kenji; Arita, Makoto; Arai, Hiroyuki; Lambeau, Gérard; Bollinger, James M.; Hara, Shuntaro; Gelb, Michael H.

    2013-01-01

    Resolution of inflammation is an active process that is mediated in part by antiinflammatory lipid mediators. Although phospholipase A2 (PLA2) enzymes have been implicated in the promotion of inflammation through mobilizing lipid mediators, the molecular entity of PLA2 subtypes acting upstream of antiinflammatory lipid mediators remains unknown. Herein, we show that secreted PLA2 group IID (PLA2G2D) is preferentially expressed in CD11c+ dendritic cells (DCs) and macrophages and displays a pro-resolving function. In hapten-induced contact dermatitis, resolution, not propagation, of inflammation was compromised in skin and LNs of PLA2G2D-deficient mice (Pla2g2d−/−), in which the immune balance was shifted toward a proinflammatory state over an antiinflammatory state. Bone marrow-derived DCs from Pla2g2d−/− mice were hyperactivated and elicited skin inflammation after intravenous transfer into mice. Lipidomics analysis revealed that PLA2G2D in the LNs contributed to mobilization of a pool of polyunsaturated fatty acids that could serve as precursors for antiinflammatory/pro-resolving lipid mediators such as resolvin D1 and 15-deoxy-Δ12,14-prostaglandin J2, which reduced Th1 cytokine production and surface MHC class II expression in LN cells or DCs. Altogether, our results highlight PLA2G2D as a “resolving sPLA2” that ameliorates inflammation through mobilizing pro-resolving lipid mediators and points to a potential use of this enzyme for treatment of inflammatory disorders. PMID:23690440

  15. Siomycin A targets brain tumor stem cells partially through a MELK-mediated pathway.

    Science.gov (United States)

    Nakano, Ichiro; Joshi, Kaushal; Visnyei, Koppany; Hu, Bin; Watanabe, Momoko; Lam, Diana; Wexler, Eric; Saigusa, Kuniyasu; Nakamura, Yuko; Laks, Dan R; Mischel, Paul S; Viapiano, Mariano; Kornblum, Harley I

    2011-06-01

    Glioblastoma multiforme (GBM) is a devastating disease, and the current therapies have only palliative effect. Evidence is mounting to indicate that brain tumor stem cells (BTSCs) are a minority of tumor cells that are responsible for cancer initiation, propagation, and maintenance. Therapies that fail to eradicate BTSCs may ultimately lead to regrowth of residual BTSCs. However, BTSCs are relatively resistant to the current treatments. Development of novel therapeutic strategies that effectively eradicate BTSC are, therefore, essential. In a previous study, we used patient-derived GBM sphere cells (stemlike GBM cells) to enrich for BTSC and identified maternal embryonic leucine-zipper kinase (MELK) as a key regulator of survival of stemlike GBM cells in vitro. Here, we demonstrate that a thiazole antibiotic, siomycin A, potently reduced MELK expression and inhibited tumor growth in vivo. Treatment of stemlike GBM cells with siomycin A resulted in arrested self-renewal, decreased invasion, and induced apoptosis but had little effect on growth of the nonstem cells of matched tumors or normal neural stem/progenitor cells. MELK overexpression partially rescued the phenotype of siomycin A-treated stemlike GBM cells. In vivo, siomycin A pretreatment abraded the sizes of stemlike GBM cell-derived tumors in immunodeficient mice. Treatment with siomycin A of mice harboring intracranial tumors significantly prolonged their survival period compared with the control mice. Together, this study may be the first model to partially target stemlike GBM cells through a MELK-mediated pathway with siomycin A to pave the way for effective treatment of GBM.

  16. A Comparison of Dose Metrics to Predict Local Tumor Control for Photofrin-mediated Photodynamic Therapy.

    Science.gov (United States)

    Qiu, Haixia; Kim, Michele M; Penjweini, Rozhin; Finlay, Jarod C; Busch, Theresa M; Wang, Tianhao; Guo, Wensheng; Cengel, Keith A; Simone, Charles B; Glatstein, Eli; Zhu, Timothy C

    2017-07-01

    This preclinical study examines light fluence, photodynamic therapy (PDT) dose and "apparent reacted singlet oxygen," [(1) O2 ]rx , to predict local control rate (LCR) for Photofrin-mediated PDT of radiation-induced fibrosarcoma (RIF) tumors. Mice bearing RIF tumors were treated with in-air fluences (50-250 J cm(-2) ) and in-air fluence rates (50-150 mW cm(-2) ) at Photofrin dosages of 5 and 15 mg kg(-1) and a drug-light interval of 24 h using a 630-nm, 1-cm-diameter collimated laser. A macroscopic model was used to calculate [(1) O2 ]rx and PDT dose based on in vivo explicit dosimetry of the drug concentration, light fluence and tissue optical properties. PDT dose and [(1) O2 ]rx were defined as a temporal integral of drug concentration and fluence rate, and singlet oxygen concentration consumed divided by the singlet oxygen lifetime, respectively. LCR was stratified for different dose metrics for 74 mice (66 + 8 control). Complete tumor control at 14 days was observed for [(1) O2 ]rx ≥ 1.1 mm or PDT dose ≥1200 μm J cm(-2) but cannot be predicted with fluence alone. LCR increases with increasing [(1) O2 ]rx and PDT dose but is not well correlated with fluence. Comparing dosimetric quantities, [(1) O2 ]rx outperformed both PDT dose and fluence in predicting tumor response and correlating with LCR. © 2017 The American Society of Photobiology.

  17. The role of miR-100-mediated Notch pathway in apoptosis of gastric tumor cells.

    Science.gov (United States)

    Yang, Geng; Gong, Yi; Wang, Qizhi; Wang, Yumeng; Zhang, Xiaobo

    2015-06-01

    MicroRNAs (miRNAs) are small non-coding regulatory molecules that influence many biological functions, including apoptosis, but their role in the regulation of apoptosis in gastric tumor cells has not been intensively investigated. Here, we showed that miR-100 was specifically upregulated in human epithelium-derived gastric cancer cells and that silencing miR-100 expression in human gastric epithelial cancer cells initiated a robust apoptotic response in vitro. Our in vivo assays indicated that the development of gastric cancer was inhibited by the miR-100 antagonism via initiating apoptosis of tumor. The results presented that antagonism of miR-100 increased the expression level of HS3ST2, the target gene of miR-100, and further resulted in the activation of the Notch-apoptosis pathway in tumor cells. The data also revealed that silencing of miR-100 expression sensitized gastric cancer cells to chemotherapy. Therefore our study presented a novel miR-100 mediated Notch pathway in apoptosis of tumor cells.

  18. Nanoparticle-mediated combination chemotherapy and photodynamic therapy overcomes tumor drug resistance in vitro.

    Science.gov (United States)

    Khdair, Ayman; Handa, Hitesh; Mao, Guangzhao; Panyam, Jayanth

    2009-02-01

    Drug resistance limits the success of many anticancer drugs. Reduced accumulation of the drug at its intracellular site of action because of overexpression of efflux transporters such as P-glycoprotein (P-gp) is a major mechanism of drug resistance. In this study, we investigated whether photodynamic therapy (PDT) using methylene blue, also a P-gp inhibitor, can be used to enhance doxorubicin-induced cytotoxicity in drug-resistant tumor cells. Aerosol OT (AOT)-alginate nanoparticles were used as a carrier for the simultaneous cellular delivery of doxorubicin and methylene blue. Methylene blue was photoactivated using light of 665 nm wavelength. Induction of apoptosis and necrosis following treatment with combination chemotherapy and PDT was investigated in drug-resistant NCI/ADR-RES cells using flow cytometry and fluorescence microscopy. Effect of encapsulation in nanoparticles on the intracellular accumulation of doxorubicin and methylene blue was investigated qualitatively using fluorescence microscopy and was quantitated using HPLC. Encapsulation in AOT-alginate nanoparticles significantly enhanced the cytotoxicity of combination therapy in resistant tumor cells. Nanoparticle-mediated combination therapy resulted in a significant induction of both apoptosis and necrosis. Improvement in cytotoxicity could be correlated with enhanced intracellular and nuclear delivery of the two drugs. Further, nanoparticle-mediated combination therapy resulted in significantly elevated reactive oxygen species (ROS) production compared to single drug treatment. In conclusion, nanoparticle-mediated combination chemotherapy and PDT using doxorubicin and methylene blue was able to overcome resistance mechanisms and resulted in improved cytotoxicity in drug-resistant tumor cells.

  19. Leptin as a mediator of tumor-stromal interactions promotes breast cancer stem cell activity.

    Science.gov (United States)

    Giordano, Cinzia; Chemi, Francesca; Panza, Salvatore; Barone, Ines; Bonofiglio, Daniela; Lanzino, Marilena; Cordella, Angela; Campana, Antonella; Hashim, Adnan; Rizza, Pietro; Leggio, Antonella; Győrffy, Balázs; Simões, Bruno M; Clarke, Robert B; Weisz, Alessandro; Catalano, Stefania; Andò, Sebastiano

    2016-01-12

    Breast cancer stem cells (BCSCs) play crucial roles in tumor initiation, metastasis and therapeutic resistance. A strict dependency between BCSCs and stromal cell components of tumor microenvironment exists. Thus, novel therapeutic strategies aimed to target the crosstalk between activated microenvironment and BCSCs have the potential to improve clinical outcome. Here, we investigated how leptin, as a mediator of tumor-stromal interactions, may affect BCSC activity using patient-derived samples (n = 16) and breast cancer cell lines, and determined the potential benefit of targeting leptin signaling in these model systems. Conditioned media (CM) from cancer-associated fibroblasts and breast adipocytes significantly increased mammosphere formation in breast cancer cells and depletion of leptin from CM completely abrogated this effect. Mammosphere cultures exhibited increased leptin receptor (OBR) expression and leptin exposure enhanced mammosphere formation. Microarray analyses revealed a similar expression profile of genes involved in stem cell biology among mammospheres treated with CM and leptin. Interestingly, leptin increased mammosphere formation in metastatic breast cancers and expression of OBR as well as HSP90, a target of leptin signaling, were directly correlated with mammosphere formation in metastatic samples (r = 0.68/p = 0.05; r = 0.71/p = 0.036, respectively). Kaplan-Meier survival curves indicated that OBR and HSP90 expression were associated with reduced overall survival in breast cancer patients (HR = 1.9/p = 0.022; HR = 2.2/p = 0.00017, respectively). Furthermore, blocking leptin signaling by using a full leptin receptor antagonist significantly reduced mammosphere formation in breast cancer cell lines and patient-derived samples. Our results suggest that leptin/leptin receptor signaling may represent a potential therapeutic target that can block the stromal-tumor interactions driving BCSC-mediated disease progression.

  20. Baculovirus vector-mediated transfer of NIS gene into colon tumor cells for radionuclide therapy

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    AIM:To investigate the feasibility of radionuclide therapy of colon tumor cells by baculovirus vector-mediated transfer of the sodium/iodide symporter(NIS) gene.METHODS:A recombinant baculovirus plasmid carrying the NIS gene was constructed,and the viruses(BacNIS) were prepared using the Bac-to-Bac system.The infection efficiency in the colon cancer cell line SW1116 of a green fluorescent protein(GFP) expressing baculovirus(Bac-GFP) at different multiplicities of infection(MOI) with various concentrations o...

  1. Discovery of Prostate Cancer Tumor Suppressors and Mediators of MDV3100 Resistance Through in Vivo RNA Interference Screen

    Science.gov (United States)

    2015-11-01

    AWARD NUMBER: W81XWH-13-1-0084 TITLE: Discovery of Prostate Cancer Tumor Suppressors and Mediators of MDV3100 Resistance through in Vivo...Suppressors and Mediators of MDV3100 Resistance through in Vivo RNA Interference Screen 5b. GRANT NUMBER W81XWH-13-1-0084 5c. PROGRAM ELEMENT NUMBER 6...Public Release; Distribution Unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT We set out to identify factors that mediate resistance to enzalutamide

  2. Cyclophosphamide chemotherapy sensitizes tumor cells to TRAIL-dependent CD8 T cell-mediated immune attack resulting in suppression of tumor growth.

    Directory of Open Access Journals (Sweden)

    Robbert G van der Most

    Full Text Available BACKGROUND: Anti-cancer chemotherapy can be simultaneously lymphodepleting and immunostimulatory. Pre-clinical models clearly demonstrate that chemotherapy can synergize with immunotherapy, raising the question how the immune system can be mobilized to generate anti-tumor immune responses in the context of chemotherapy. METHODS AND FINDINGS: We used a mouse model of malignant mesothelioma, AB1-HA, to investigate T cell-dependent tumor resolution after chemotherapy. Established AB1-HA tumors were cured by a single dose of cyclophosphamide in a CD8 T cell- and NK cell-dependent manner. This treatment was associated with an IFN-alpha/beta response and a profound negative impact on the anti-tumor and total CD8 T cell responses. Despite this negative effect, CD8 T cells were essential for curative responses. The important effector molecules used by the anti-tumor immune response included IFN-gamma and TRAIL. The importance of TRAIL was supported by experiments in nude mice where the lack of functional T cells could be compensated by agonistic anti-TRAIL-receptor (DR5 antibodies. CONCLUSION: The data support a model in which chemotherapy sensitizes tumor cells for T cell-, and possibly NK cell-, mediated apoptosis. A key role of tumor cell sensitization to immune attack is supported by the role of TRAIL in tumor resolution and explains the paradox of successful CD8 T cell-dependent anti-tumor responses in the absence of CD8 T cell expansion.

  3. Targeting hypoxia-mediated mucin 2 production as a therapeutic strategy for mucinous tumors.

    Science.gov (United States)

    Dilly, Ashok K; Lee, Yong J; Zeh, Herbert J; Guo, Zong Sheng; Bartlett, David L; Choudry, Haroon A

    2016-03-01

    Excessive accumulation of mucin 2 (MUC2; a gel-forming secreted mucin) protein in the peritoneal cavity is the major cause of morbidity and mortality in pseudomyxoma peritonei (PMP). Hypoxia (hypoxia-inducible factor-1α; HIF-1α) has been shown to regulate the expression of similar mucins (eg, MUC5AC). We hypothesized that hypoxia (HIF-1α) drives MUC2 expression in PMP and is therefore a novel target to reduce mucinous tumor growth. The regulation of MUC2 by 2% hypoxia (HIF-1α) was evaluated in MUC2-secreting LS174T cells. The effect of BAY 87-2243, an inhibitor of HIF-1α, on MUC2 expression and mucinous tumor growth was evaluated in LS174T cells, PMP explant tissue, and in a unique intraperitoneal murine xenograft model of PMP. In vitro exposure of LS174T cells to hypoxia increased MUC2 messenger RNA (mRNA) and protein expression and increased HIF-1α binding to the MUC2 promoter. Hypoxia-mediated MUC2 protein overexpression was downregulated by transfected HIF-1α small interfering RNA (siRNA) compared with scrambled siRNA in LS174T cells. BAY 87-2243 inhibited hypoxia-induced MUC2 mRNA and protein expression in LS174T cells and PMP explant tissue. In a murine xenograft model of PMP, chronic oral therapy with BAY 87-2243 inhibited mucinous tumor growth and MUC2, HIF-1α expression in the tumor tissue. Our data suggest that hypoxia (HIF-1α) induces MUC2 promoter activity to increase MUC2 expression. HIF-1α inhibition decreases MUC2 production and mucinous tumor growth, providing a preclinical rationale for the use of HIF-1α inhibitors to treat patients with PMP.

  4. Local hyperthermia treatment of tumors induces CD8+ T cell-mediated resistance against distal and secondary tumors

    Science.gov (United States)

    Zhang, Peisheng; Chen, Lei; Baird, Jason R.; Demidenko, Eugene; Turk, Mary Jo; Hoopes, P. Jack; Conejo-Garcia, Jose R.; Fiering, Steven

    2014-01-01

    Combinatorial use of iron oxide nanoparticles (IONPs) and an alternating magnetic filed (AMF) can induce local hyperthermia in tumors in a controlled and uniform manner. Heating B16 primary tumors at 43°C for 30 minutes activated dendritic cells (DCs) and subsequently CD8+ T cells in the draining lymph node (dLN) and conferred resistance against rechallenge with B16 (but not unrelated Lewis Lung carcinoma) given 7 days post hyperthermia on both the primary tumor side and the contralateral side in a CD8+ T cell-dependent manner. Mice with heated primary tumors also resisted rechallenge given 30 days post hyperthermia. Mice with larger heated primary tumors had greater resistance to secondary tumors. No rechallenge resistance occurred when tumors were heated at 45°C. Our results demonstrate the promising potential of local hyperthermia treatment applied to identified tumors in inducing anti-tumor immune responses that reduce the risk of recurrence and metastasis. PMID:24566274

  5. Attenuated Listeria monocytogenes reprograms M2-polarized tumor-associated macrophages in ovarian cancer leading to iNOS-mediated tumor cell lysis.

    Science.gov (United States)

    Lizotte, Patrick H; Baird, Jason R; Stevens, Cynthia A; Lauer, Peter; Green, William R; Brockstedt, Dirk G; Fiering, Steven N

    2014-01-01

    A principal mechanism by which tumors evade immune-mediated elimination is through immunosuppression. Previous approaches to tumor immunotherapy have focused on modifying the immunosuppressive environment with immune checkpoint inhibitors, cytokine therapy, and other modalities with the intent to generate T-cell based anti-tumor immunity. We hypothesized that transformation of the suppressive ovarian cancer microenvironment could be achieved by introduction of the attenuated ΔactA/ΔinlB strain of Listeria monocytogenes. ΔactA/ΔinlB introduced into the microenvironment of the aggressive ID8-Defb29/Vegf-A murine ovarian carcinoma is preferentially phagocytosed by tumor-associated macrophages (TAMs) and reprograms that population from one of suppression to immunostimulation. TAMs in the peritoneum upregulated their co-stimulatory molecules CD80 and CD86, increased transcription of inflammatory cytokines, and downregulated transcription of suppressive effector molecules. Surprisingly, therapeutic benefit was not mediated by T- or NK-cell activity. ΔactA/ΔinlB-induced repolarization of TAMs activated direct tumor cell lysis via Nos2 production of nitric oxide. Modulation of the immunosuppressive nature of the ID8-Defb29/Vegf-A microenvironment, specifically by reprogramming of the TAM suppressive population from M2 to M1 polarization, is critical for our observed immune-mediated survival benefit.

  6. Bacterial outer membrane vesicles suppress tumor by interferon-γ-mediated antitumor response.

    Science.gov (United States)

    Kim, Oh Youn; Park, Hyun Taek; Dinh, Nhung Thi Hong; Choi, Seng Jin; Lee, Jaewook; Kim, Ji Hyun; Lee, Seung-Woo; Gho, Yong Song

    2017-09-20

    Gram-negative bacteria actively secrete outer membrane vesicles, spherical nano-meter-sized proteolipids enriched with outer membrane proteins, to the surroundings. Outer membrane vesicles have gained wide interests as non-living complex vaccines or delivery vehicles. However, no study has used outer membrane vesicles in treating cancer thus far. Here we investigate the potential of bacterial outer membrane vesicles as therapeutic agents to treat cancer via immunotherapy. Our results show remarkable capability of bacterial outer membrane vesicles to effectively induce long-term antitumor immune responses that can fully eradicate established tumors without notable adverse effects. Moreover, systematically administered bacterial outer membrane vesicles specifically target and accumulate in the tumor tissue, and subsequently induce the production of antitumor cytokines CXCL10 and interferon-γ. This antitumor effect is interferon-γ dependent, as interferon-γ-deficient mice could not induce such outer membrane vesicle-mediated immune response. Together, our results herein demonstrate the potential of bacterial outer membrane vesicles as effective immunotherapeutic agent that can treat various cancers without apparent adverse effects.Bacterial outer membrane vesicles (OMVs) contain immunogens but no study has yet examined their potential in treating cancer. Here, the authors demonstrate that OMVs can suppress established tumours and prevent tumour metastasis by an interferon-γ mediated antitumor response.

  7. Downregulation of c-Myc is involved in TLR3-mediated tumor death of neuroblastoma xenografts.

    Science.gov (United States)

    Lin, Li-Ling; Huang, Chao-Cheng; Wu, Chia-Ling; Wu, Min-Tsui; Hsu, Wen-Ming; Chuang, Jiin-Haur

    2016-07-01

    Neuroblastoma (NB) is the deadliest pediatric solid tumor due to its pleomorphic molecular characteristics. In the innate immune system, toll-like receptor 3 (TLR3) recognizes viral double-stranded RNAs to initiate immune signaling. Positive TLR3 expression indicates a favorable prognosis in NB patients, and is associated with MYCN-non-amplified. However, TLR3-mediated innate immune responses remain elusive in NB. In this study, we attempted to dissect the molecular mechanism underlying TLR3-agonist polyinosinic-polycytidylic acid [poly(I:C)] treatment in NB in vivo. We established NB xenograft models in non-obese diabetic/severe combined immunodeficiency (NOD/SCID) mice with MYCN-amplified SK-N-DZ (DZ) cells or MYCN-non-amplified SK-N-AS (AS) cells. Poly(I:C) treatment led to significant tumor regression in AS xenografts, but not in DZ xenografts. Through immunohistochemical analysis, significant suppression of tumor proliferation, downregulation of c-Myc expression, and upregulation of TLR3 expression were found in the treatment group. Poly(I:C) inducing activation of TLR3/IRF3-mediated innate immunity associated with downregulation of c-Myc can be found in MYCN-non-amplified SK-N-AS cells, but not in MYCN-amplified BE(2)-M17 cells. Knockdown of TLR3 disturbed poly(I:C)-induced suppression of c-Myc and upregulation of p-IRF3 in AS cells. Furthermore, poly(I:C) treatment upregulated active NF-κB, mitochondrial antioxidant manganese superoxide dismutase and 8-hydroxydeoxyguanosine, which works with reactive oxygen species (ROS) generation and DNA damage. Upregulation of active caspase 3 and cleaved poly [ADP-ribose] polymerase 1 were found in poly(I:C)-treated AS xenografts, which indicates the induction of apoptosis. Thus, our results suggest that c-Myc overexpression may increase sensitivity to poly(I:C)-induced tumor growth arrest and ROS-mediated apoptosis in NB. This study demonstrates that c-Myc protein expression has an important role in TLR3-induced innate

  8. Is the anti-tumor property of Trypanosoma cruzi infection mediated by its Calreticulin?

    Directory of Open Access Journals (Sweden)

    Galia Andrea Ramírez-Toloza

    2016-07-01

    Full Text Available Eight to 10 million people in 21 endemic countries are infected with Trypanosoma cruzi. However, only 30% of those infected develop symptoms of Chagas’ disease, a chronic, neglected tropical disease worldwide. Similar to other pathogens, T. cruzi has evolved to resist the host immune response. Studies, performed 80 years ago in the Soviet Union, proposed that T. cruzi infects tumor cells with similar capacity to that displayed for target tissues such as cardiac, aortic or digestive. An antagonistic relationship between T. cruzi infection and cancer development was also proposed, but the molecular mechanisms involved have remained largely unknown. Probably, a variety of T. cruzi molecules is involved. This review focuses on how T. cruzi calreticulin (TcCRT, exteriorized from the endoplasmic reticulum, targets the first classical complement component C1 and negatively regulates the Classical Complement activation cascade, promoting parasite infectivity. We propose that this C1-dependent TcCRT-mediated virulence is critical to explain, at least an important part, of the parasite capacity to inhibit tumor development. We will discuss how TcCRT, by directly interacting with venous and arterial endothelial cells, inhibits angiogenesis and tumor growth. Thus, these TcCRT functions not only illustrate T. cruzi interactions with the host immune defensive strategies, but also illustrate a possible co-evolutionary adaptation to privilege a prolonged interaction with its host.

  9. Meganuclease-mediated virus self-cleavage facilitates tumor-specific virus replication.

    Science.gov (United States)

    Gürlevik, Engin; Schache, Peter; Goez, Anneliese; Kloos, Arnold; Woller, Norman; Armbrecht, Nina; Manns, Michael P; Kubicka, Stefan; Kühnel, Florian

    2013-09-01

    Meganucleases can specifically cleave long DNA sequence motifs, a feature that makes them an ideal tool for gene engineering in living cells. In a proof-of-concept study, we investigated the use of the meganuclease I-Sce I for targeted virus self-disruption to generate high-specific oncolytic viruses. For this purpose, we provided oncolytic adenoviruses with a molecular circuit that selectively responds to p53 activation by expression of I-Sce I subsequently leading to self-disruption of the viral DNA via heterologous I-Sce I recognition sites within the virus genome. We observed that virus replication and cell lysis was effectively impaired in p53-normal cells, but not in p53-dysfunctional tumor cells. I-Sce I activity led to effective intracellular processing of viral DNA as confirmed by detection of specific cleavage products. Virus disruption did not interfere with E1A levels indicating that reduction of functional virus genomes was the predominant cause for conditional replication. Consequently, tumor-specific replication was further enhanced when E1A expression was additionally inhibited by targeted transcriptional repression. Finally, we demonstrated p53-dependent oncolysis by I-Sce I-expressing viruses in vitro and in vivo, and demonstrated effective inhibition of tumor growth. In summary, meganuclease-mediated virus cleavage represents a promising approach to provide oncolytic viruses with attractive safety profiles.

  10. Bispecific T cell engager (BiTE®) antibody constructs can mediate bystander tumor cell killing

    Science.gov (United States)

    Ross, Sandra L.; Sherman, Marika; McElroy, Patricia L.; Lofgren, Julie A.; Moody, Gordon; Baeuerle, Patrick A.; Coxon, Angela

    2017-01-01

    For targets that are homogenously expressed, such as CD19 on cells of the B lymphocyte lineage, immunotherapies can be highly effective. Targeting CD19 with blinatumomab, a CD19/CD3 bispecific antibody construct (BiTE®), or with chimeric antigen receptor T cells (CAR-T) has shown great promise for treating certain CD19-positive hematological malignancies. In contrast, solid tumors with heterogeneous expression of the tumor-associated antigen (TAA) may present a challenge for targeted therapies. To prevent escape of TAA-negative cancer cells, immunotherapies with a local bystander effect would be beneficial. As a model to investigate BiTE®-mediated bystander killing in the solid tumor setting, we used epidermal growth factor receptor (EGFR) as a target. We measured lysis of EGFR-negative populations in vitro and in vivo when co-cultured with EGFR-positive cells, human T cells and an EGFR/CD3 BiTE® antibody construct. Bystander EGFR-negative cells were efficiently lysed by BiTE®-activated T cells only when proximal to EGFR-positive cells. Our mechanistic analysis suggests that cytokines released by BiTE®-activated T-cells induced upregulation of ICAM-1 and FAS on EGFR-negative bystander cells, contributing to T cell-induced bystander cell lysis. PMID:28837681

  11. The nonsense-mediated RNA decay pathway is disrupted in inflammatory myofibroblastic tumors.

    Science.gov (United States)

    Lu, JingWei; Plank, Terra-Dawn; Su, Fang; Shi, XiuJuan; Liu, Chen; Ji, Yuan; Li, ShuaiJun; Huynh, Andrew; Shi, Chao; Zhu, Bo; Yang, Guang; Wu, YanMing; Wilkinson, Miles F; Lu, YanJun

    2016-08-01

    Inflammatory myofibroblastic tumors (IMTs) are characterized by myofibroblast proliferation and an inflammatory cell infiltrate. Little is known about the molecular pathways that precipitate IMT formation. Here, we report the identification of somatic mutations in UPF1, a gene that encodes an essential component of the nonsense-mediated RNA decay (NMD) pathway, in 13 of 15 pulmonary IMT samples. The majority of mutations occurred in a specific region of UPF1 and triggered UPF1 alternative splicing. Several mRNA targets of the NMD pathway were upregulated in IMT samples, indicating that the UPF1 mutations led to reduced NMD magnitude. These upregulated NMD targets included NIK mRNA, which encodes a potent activator of NF-κB. In human lung cells, UPF1 depletion increased expression of chemokine-encoding genes in a NIK-dependent manner. Elevated chemokines and IgE class switching events were observed in IMT samples, consistent with NIK upregulation in these tumors. Together, these results support a model in which UPF1 mutations downregulate NMD, leading to NIK-dependent NF-κB induction, which contributes to the immune infiltration that is characteristic of IMTs. The molecular link between the NMD pathway and IMTs has implications for the diagnosis and treatment of these tumors.

  12. Sleep-mediated heart rate variability after bilateral carotid body tumor resection.

    Science.gov (United States)

    Niemeijer, Nicolasine D; Corssmit, Eleonora P M; Reijntjes, Robert H A M; Lammers, Gert Jan; van Dijk, J Gert; Thijs, Roland D

    2015-04-01

    The carotid bodies are thought to play an important role in sleep-dependent autonomic changes. Patients who underwent resection of bilateral carotid body tumors have chronically attenuated baroreflex sensitivity. These subjects provide a unique opportunity to investigate the role of the baroreflex during sleep. One-night ambulatory polysomnography (PSG) recording. Participants' homes. Nine patients with bilateral carotid body tumor resection (bCBR) (four women, mean age 50.4 ± 7.2 years) and nine controls matched for age, gender, and body mass index. N/A. Sleep parameters were obtained from PSG. Heart rate (HR) and its variability were calculated using 30-s epochs. In bCBR patients, HR was slightly but not significantly increased during wake and all sleep stages. The effect of sleep on HR was similar for patients and controls. Low frequency (LF) power of the heart rate variability spectrum was significantly lower in bCBR patients in active wakefulness, sleep stage 1 and REM sleep. No differences were found between patients and controls for high frequency (HF) power and the LF/HF ratio. Bilateral carotid body tumor resection (bCBR) is associated with decreased low frequency power during sleep, suggesting impaired baroreflex function. Despite this, sleep-related heart rate changes were similar between bCBR patients and controls. These findings suggest that the effects of sleep on heart rate are predominantly generated through central, non-baroreflex mediated pathways. © 2015 Associated Professional Sleep Societies, LLC.

  13. Hapten-Induced Contact Hypersensitivity, Autoimmune Reactions, and Tumor Regression: Plausibility of Mediating Antitumor Immunity

    Directory of Open Access Journals (Sweden)

    Dan A. Erkes

    2014-01-01

    Full Text Available Haptens are small molecule irritants that bind to proteins and elicit an immune response. Haptens have been commonly used to study allergic contact dermatitis (ACD using animal contact hypersensitivity (CHS models. However, extensive research into contact hypersensitivity has offered a confusing and intriguing mechanism of allergic reactions occurring in the skin. The abilities of haptens to induce such reactions have been frequently utilized to study the mechanisms of inflammatory bowel disease (IBD to induce autoimmune-like responses such as autoimmune hemolytic anemia and to elicit viral wart and tumor regression. Hapten-induced tumor regression has been studied since the mid-1900s and relies on four major concepts: (1 ex vivo haptenation, (2 in situ haptenation, (3 epifocal hapten application, and (4 antigen-hapten conjugate injection. Each of these approaches elicits unique responses in mice and humans. The present review attempts to provide a critical appraisal of the hapten-mediated tumor treatments and offers insights for future development of the field.

  14. IgE/FcεRI-Mediated Antigen Cross-Presentation by Dendritic Cells Enhances Anti-Tumor Immune Responses

    Directory of Open Access Journals (Sweden)

    Barbara Platzer

    2015-03-01

    Full Text Available Epidemiologic studies discovered an inverse association between immunoglobulin E (IgE-mediated allergies and cancer, implying tumor-protective properties of IgE. However, the underlying immunologic mechanisms remain poorly understood. Antigen cross-presentation by dendritic cells (DCs is of key importance for anti-tumor immunity because it induces the generation of cytotoxic CD8+ T lymphocytes (CTLs with specificity for tumor antigens. We demonstrate that DCs use IgE and FcεRI, the high-affinity IgE receptor, for cross-presentation and priming of CTLs in response to free soluble antigen at low doses. Importantly, IgE/FcεRI-mediated cross-presentation is a distinct receptor-mediated pathway because it does not require MyD88 signals or IL-12 induction in DCs. Using passive immunization with tumor antigen-specific IgE and DC-based vaccination experiments, we demonstrate that IgE-mediated cross-presentation significantly improves anti-tumor immunity and induces memory responses in vivo. Our findings suggest a cellular mechanism for the tumor-protective features of IgE and expand the known physiological functions of this immunoglobulin.

  15. Genes encoding phospholipases A2 mediate insect nodulation reactions to bacterial challenge.

    Science.gov (United States)

    Shrestha, Sony; Park, Yoonseong; Stanley, David; Kim, Yonggyun

    2010-03-01

    We propose that expression of four genes encoding secretory phospholipases A(2) (sPLA(2)) mediates insect nodulation responses to bacterial infection. Nodulation is the quantitatively predominant cellular defense reaction to bacterial infection. This reaction is mediated by eicosanoids, the biosynthesis of which depends on PLA(2)-catalyzed hydrolysis of arachidonic acid (AA) from cellular phospholipids. Injecting late instar larvae of the red flour beetle, Tribolium castaneum, with the bacterium, Escherichia coli, stimulated nodulation reactions and sPLA(2) activity in time- and dose-related manners. Nodulation was inhibited by pharmaceutical inhibitors of enzymes involved in eicosanoid biosynthesis, and the inhibition was rescued by AA. We cloned five genes encoding sPLA(2) and expressed them in E. coli cells to demonstrate these genes encode catalytically active sPLA(2)s. The recombinant sPLA(2)s were inhibited by sPLA(2) inhibitors. Injecting larvae with double-stranded RNAs specific to each of the five genes led to reduced expression of the corresponding sPLA(2) genes and to reduced nodulation reactions to bacterial infections for four of the five genes. The reduced nodulation was rescued by AA, indicating that expression of four genes encoding sPLA(2)s mediates nodulation reactions. A polyclonal antibody that reacted with all five sPLA(2)s showed the presence of the sPLA(2) enzymes in hemocytes and revealed that the enzymes were more closely associated with hemocyte plasma membranes following infection. Identifying specific sPLA(2) genes that mediate nodulation reactions strongly supports our hypothesis that sPLA(2)s are central enzymes in insect cellular immune reactions. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

  16. Androgen receptor is the key transcriptional mediator of the tumor suppressor SPOP in prostate cancer.

    Science.gov (United States)

    Geng, Chuandong; Rajapakshe, Kimal; Shah, Shrijal S; Shou, John; Eedunuri, Vijay Kumar; Foley, Christopher; Fiskus, Warren; Rajendran, Mahitha; Chew, Sue Anne; Zimmermann, Martin; Bond, Richard; He, Bin; Coarfa, Cristian; Mitsiades, Nicholas

    2014-10-01

    Somatic missense mutations in the substrate-binding pocket of the E3 ubiquitin ligase adaptor SPOP are present in up to 15% of human prostate adenocarcinomas, but are rare in other malignancies, suggesting a prostate-specific mechanism of action. SPOP promotes ubiquitination and degradation of several protein substrates, including the androgen receptor (AR) coactivator SRC-3. However, the relative contributions that SPOP substrates may make to the pathophysiology of SPOP-mutant (mt) prostate adenocarcinomas are unknown. Using an unbiased bioinformatics approach, we determined that the gene expression profile of prostate adenocarcinoma cells engineered to express mt-SPOP overlaps greatly with the gene signature of both SRC-3 and AR transcriptional output, with a stronger similarity to AR than SRC-3. This finding suggests that in addition to its SRC-3-mediated effects, SPOP also exerts SRC-3-independent effects that are AR-mediated. Indeed, we found that wild-type (wt) but not prostate adenocarcinoma-associated mutants of SPOP promoted AR ubiquitination and degradation, acting directly through a SPOP-binding motif in the hinge region of AR. In support of these results, tumor xenografts composed of prostate adenocarcinoma cells expressing mt-SPOP exhibited higher AR protein levels and grew faster than tumors composed of prostate adenocarcinoma cells expressing wt-SPOP. Furthermore, genetic ablation of SPOP was sufficient to increase AR protein levels in mouse prostate. Examination of public human prostate adenocarcinoma datasets confirmed a strong link between transcriptomic profiles of mt-SPOP and AR. Overall, our studies highlight the AR axis as the key transcriptional output of SPOP in prostate adenocarcinoma and provide an explanation for the prostate-specific tumor suppressor role of wt-SPOP.

  17. Protective role of p21(Waf1/Cip1) against prostaglandin A2-mediated apoptosis of human colorectal carcinoma cells.

    Science.gov (United States)

    Gorospe, M; Wang, X; Guyton, K Z; Holbrook, N J

    1996-01-01

    Prostaglandin A2 (PGA2) suppresses tumor growth in vivo, is potently antiproliferative in vitro, and is a model drug for the study of the mammalian stress response. Our previous studies using breast carcinoma MCF-7 cells suggested that p21(Waf1/Cip1) induction enabled cells to survive PGA2 exposure. Indeed, the marked sensitivity of human colorectal carcinoma RKO cells to the cytotoxicity of PGA2 is known to be associated with a lack of a PGA2-mediated increase in p21(Waf1/Cip1) expression, inhibition of cyclin-dependent kinase activity, and growth arrest. To determine if cell death following exposure to PGA2 could be prevented by forcing the expression of p21(Waf1/Cip1) in RKO cells, we utilized an adenoviral vector-based expression system. We demonstrate that ectopic expression of p21(Waf1/Cip1) largely rescued RKO cells from PGA2-induced apoptotic cell death, directly implicating p21(Waf1/Cip1) as a determinant of the cellular outcome (survival versus death) following exposure to PGA2. To discern whether p21(Waf1/Cip1)-mediated protection operates through the implementation of cellular growth arrest, other growth-inhibitory treatments were studied for the ability to attenuate PGA2-induced cell death. Neither serum depletion nor suramin (a growth factor receptor antagonist) protected RKO cells against PGA2 cytotoxicity, and neither induced p21(Waf1/Cip1) expression. Mimosine, however, enhanced p21(Waf1/Cip1) expression, completely inhibited RKO cell proliferation, and exerted marked protection against a subsequent PGA2 challenge. Taken together, our results directly demonstrate a protective role for p21(Waf1/Cip1) during PGA2 cellular stress and provide strong evidence that the implementation of cellular growth arrest contributes to this protective influence. PMID:8943319

  18. Effects of Panax ginseng on Tumor Necrosis Factor-α-Mediated Inflammation: A Mini-Review

    Directory of Open Access Journals (Sweden)

    Davy CW Lee

    2011-03-01

    Full Text Available Panax ginseng is one of the most commonly used Chinese medicines in China, Asia and Western countries. The beneficial effects of ginseng have been attributed to the biological activities of its constituents, the ginsenosides. In this review, we summarize recent publications on the anti-inflammatory effects of ginseng extracts and ginsenosides on cellular responses triggered by different inducers including endotoxin, tumor necrosis factor-alpha (TNF-α, interferon-gamma and other stimuli. Proinflammatory cytokines, chemokines, adhesion molecules and mediators of inflammation including inducible nitric oxide synthase, cyclooxygenase-2 and nitric oxide orchestrate the inflammatory response. Ginseng extracts and ginsenosides including Rb1, Rd, Rg1, Rg3, Rh1, Rh2, Rh3 and Rp1 have been reported to have anti-inflammatory properties in different studies related to inflammation. Ginsenosides inhibit different inducers-activated signaling protein kinases and transcription factor nuclear factor-kappaB leading to decreases in the production of cytokines and mediators of inflammation. The therapeutic potential of ginseng on TNF-α-mediated inflammatory diseases is also discussed. Taken together, this summary provides evidences for the anti-inflammatory effects of ginseng extracts and ginsenosides as well as the underlying mechanisms of their effects on inflammatory diseases.

  19. Calcium-activated potassium channels mediated blood-brain tumor barrier opening in a rat metastatic brain tumor model

    Directory of Open Access Journals (Sweden)

    Ong John M

    2007-03-01

    Full Text Available Abstract Background The blood-brain tumor barrier (BTB impedes the delivery of therapeutic agents to brain tumors. While adequate delivery of drugs occurs in systemic tumors, the BTB limits delivery of anti-tumor agents into brain metastases. Results In this study, we examined the function and regulation of calcium-activated potassium (KCa channels in a rat metastatic brain tumor model. We showed that intravenous infusion of NS1619, a KCa channel agonist, and bradykinin selectively enhanced BTB permeability in brain tumors, but not in normal brain. Iberiotoxin, a KCa channel antagonist, significantly attenuated NS1619-induced BTB permeability increase. We found KCa channels and bradykinin type 2 receptors (B2R expressed in cultured human metastatic brain tumor cells (CRL-5904, non-small cell lung cancer, metastasized to brain, human brain microvessel endothelial cells (HBMEC and human lung cancer brain metastasis tissues. Potentiometric assays demonstrated the activity of KCa channels in metastatic brain tumor cells and HBMEC. Furthermore, we detected higher expression of KCa channels in the metastatic brain tumor tissue and tumor capillary endothelia as compared to normal brain tissue. Co-culture of metastatic brain tumor cells and brain microvessel endothelial cells showed an upregulation of KCa channels, which may contribute to the overexpression of KCa channels in tumor microvessels and selectivity of BTB opening. Conclusion These findings suggest that KCa channels in metastatic brain tumors may serve as an effective target for biochemical modulation of BTB permeability to enhance selective delivery of chemotherapeutic drugs to metastatic brain tumors.

  20. Radio-photothermal therapy mediated by a single compartment nanoplatform depletes tumor initiating cells and reduces lung metastasis in the orthotopic 4T1 breast tumor model

    Science.gov (United States)

    Zhou, Min; Zhao, Jun; Tian, Mei; Song, Shaoli; Zhang, Rui; Gupta, Sanjay; Tan, Dongfeng; Shen, Haifa; Ferrari, Mauro; Li, Chun

    2015-11-01

    Tumor Initiating Cells (TICs) are resistant to radiotherapy and chemotherapy, and are believed to be responsible for tumor recurrence and metastasis. Combination therapies can overcome the limitation of conventional cancer treatments, and have demonstrated promising application in the clinic. Here, we show that dual modality radiotherapy (RT) and photothermal therapy (PTT) mediated by a single compartment nanosystem copper-64-labeled copper sulfide nanoparticles ([64Cu]CuS NPs) could suppress breast tumor metastasis through eradication of TICs. Positron electron tomography (PET) imaging and biodistribution studies showed that more than 90% of [64Cu]CuS NPs was retained in subcutaneously grown BT474 breast tumor 24 h after intratumoral (i.t.) injection, indicating the NPs are suitable for the combination therapy. Combined RT/PTT therapy resulted in significant tumor growth delay in the subcutaneous BT474 breast cancer model. Moreover, RT/PTT treatment significantly prolonged the survival of mice bearing orthotopic 4T1 breast tumors compared to no treatment, RT alone, or PTT alone. The RT/PTT combination therapy significantly reduced the number of tumor nodules in the lung and the formation of tumor mammospheres from treated 4T1 tumors. No obvious side effects of the CuS NPs were noted in the treated mice in a pilot toxicity study. Taken together, our data support the feasibility of a therapeutic approach for the suppression of tumor metastasis through localized RT/PTT therapy.Tumor Initiating Cells (TICs) are resistant to radiotherapy and chemotherapy, and are believed to be responsible for tumor recurrence and metastasis. Combination therapies can overcome the limitation of conventional cancer treatments, and have demonstrated promising application in the clinic. Here, we show that dual modality radiotherapy (RT) and photothermal therapy (PTT) mediated by a single compartment nanosystem copper-64-labeled copper sulfide nanoparticles ([64Cu]CuS NPs) could suppress

  1. Cell Swelling Activates Phospholipase A2 in Ehrlich Ascites Tumor Cells

    DEFF Research Database (Denmark)

    Thoroed, S.M.; Lauritzen, L.; Lambert, I.H.

    1997-01-01

    Ehrlich ascites tumor cells! loaded with H-labeled arachidonic acid and C-labeled stearic acid for two hours, were washed and transferred to either isotonic or hypotonic media containing BSA to scavenge the labeled fatty acids released from the cells. During the first two minutes of hypo-osmotic ......Ehrlich ascites tumor cells! loaded with H-labeled arachidonic acid and C-labeled stearic acid for two hours, were washed and transferred to either isotonic or hypotonic media containing BSA to scavenge the labeled fatty acids released from the cells. During the first two minutes of hypo...

  2. Anti-tumor immunity of BAM-SiPc-mediated vascular photodynamic therapy in a BALB/c mouse model.

    Science.gov (United States)

    Yeung, Hing-Yuen; Lo, Pui-Chi; Ng, Dennis K P; Fong, Wing-Ping

    2017-02-01

    In recent decades, accumulating evidence from both animal and clinical studies has suggested that a sufficiently activated immune system may strongly augment various types of cancer treatment, including photodynamic therapy (PDT). Through the generation of reactive oxygen species, PDT eradicates tumors by triggering localized tumor damage and inducing anti-tumor immunity. As the major component of anti-tumor immunity, the involvement of a cell-mediated immune response in PDT has been well investigated in the past decade, whereas the role of humoral immunity has remained relatively unexplored. In the present investigation, using the photosensitizer BAM-SiPc and the CT26 tumor-bearing BALB/c mouse model, it was demonstrated that both cell-mediated and humoral adaptive immune components could be involved in PDT. With a vascular PDT (VPDT) regimen, BAM-SiPc could eradicate the tumors of ∼70% of tumor-bearing mice and trigger an anti-tumor immune response that could last for more than 1 year. An elevation of Th2 cytokines was detected ex vivo after VPDT, indicating the potential involvement of a humoral response. An analysis of serum from the VPDT-cured mice also revealed elevated levels of tumor-specific antibodies. Moreover, this serum could effectively hinder tumor growth and protect the mice against further re-challenge in a T-cell-dependent manner. Taken together, these results show that the humoral components induced after BAM-SiPc-VPDT could assist the development of anti-tumor immunity.

  3. Ganglioside GM2 mediates migration of tumor cells by interacting with integrin and modulating the downstream signaling pathway.

    Science.gov (United States)

    Kundu, Manjari; Mahata, Barun; Banerjee, Avisek; Chakraborty, Sohini; Debnath, Shibjyoti; Ray, Sougata Sinha; Ghosh, Zhumur; Biswas, Kaushik

    2016-07-01

    The definitive role of ganglioside GM2 in mediating tumor-induced growth and progression is still unknown. Here we report a novel role of ganglioside GM2 in mediating tumor cell migration and uncovered its mechanism. Data shows differential expression levels of GM2-synthase as well as GM2 in different human cancer cells. siRNA mediated knockdown of GM2-synthase in CCF52, A549 and SK-RC-26B cells resulted in significant inhibition of tumor cell migration as well as invasion in vitro without affecting cellular proliferation. Over-expression of GM2-synthase in low-GM2 expressing SK-RC-45 cells resulted in a consequent increase in migration thus confirming the potential role GM2 and its downstream partners play in tumor cell migration and motility. Further, treatment of SK-RC-45 cells with exogenous GM2 resulted in a dramatic increase in migratory and invasive capacity with no change in proliferative capacity, thereby confirming the role of GM2 in tumorigenesis specifically by mediating tumor migration and invasion. Gene expression profiling of GM2-synthase silenced cells revealed altered expression of several genes involved in cell migration primarily those controlling the integrin mediated signaling. GM2-synthase knockdown resulted in decreased phosphorylation of FAK, Src as well as Erk, while over-expression and/or exogenous GM2 treatment caused increased FAK and Erk phosphorylation respectively. Again, GM2 mediated invasion and Erk phosphorylation is blocked in integrin knockdown SK-RC-45 cells, thus confirming that GM2 mediated migration and phosphorylation of Erk is integrin dependent. Finally, confocal microscopy suggested co-localization while co-immunoprecipitation and surface plasmon resonance (SPR) confirmed direct interaction of membrane bound ganglioside, GM2 with the integrin receptor.

  4. Mediator complex subunit 12 exon 2 mutation analysis in different subtypes of smooth muscle tumors confirms genetic heterogeneity.

    Science.gov (United States)

    de Graaff, Marieke A; Cleton-Jansen, Anne-Marie; Szuhai, Károly; Bovée, Judith V M G

    2013-08-01

    Recently, heterozygous mutations in exon 2 of the mediator complex subunit 12 gene have been described in 50% to 70% of uterine leiomyomas; the recurrent nature of these mutations suggests an important role in their pathogenesis. Mediator complex subunit 12 is involved in regulation of transcription and Wnt signaling. So far, little is known about the pathogenesis of the different subtypes of extrauterine leiomyomas and leiomyosarcomas. We performed mutation analysis of mediator complex subunit 12 and immunohistochemistry for β-catenin, using 69 tumors of 64 patients including 19 uterine leiomyomas, 6 abdominal leiomyomas, 9 angioleiomyomas, 5 piloleiomyomas, and 7 uterine and 23 soft tissue leiomyosarcomas. In line with previous observations, 58% of uterine leiomyomas carried a mediator complex subunit 12 mutation. However, all other extrauterine leiomyomas were negative with the exception of 1 abdominal leiomyoma with a likely primary uterine origin. Of the 30 leiomyosarcomas, only 1 uterine tumor harbored a mutation. A new observation is the identification of 3 tumors with a homozygous mutation; a monosomy X or interstitial deletion was excluded. β-Catenin immunohistochemistry showed nuclear positivity in only 55% of the mediator complex subunit 12-mutated uterine leiomyomas, suggesting the involvement of pathways other than canonical Wnt signaling in tumorigenesis. Interestingly, 80% of mediator complex subunit 12 wild-type sporadic piloleiomyomas displayed nuclear β-catenin positivity, indicating its involvement in this leiomyoma subtype. The lack of mediator complex subunit 12 mutations in extrauterine leiomyomas and leiomyosarcomas indicates that these tumors arise through a different pathway, emphasizing the genetic heterogeneity of smooth muscle tumors.

  5. Dextran-functionalized magnetic fluid mediating magnetohyperthermia for treatment of Ehrlich-solid-tumor-bearing mice: toxicological and histopathological evaluations.

    Science.gov (United States)

    Miranda-Vilela, Ana Luisa; Yamamoto, Kelly Reis; Miranda, Kely Lopes Caiado; Matos, Breno Noronha; de Almeida, Marcos Célio; Longo, João Paulo Figueiró; de Souza Filho, José; Fernandes, Juliana Menezes Soares; Sartoratto, Patrícia Pommé Confessori; Lacava, Zulmira Guerrero Marques

    2014-04-01

    Dextran-functionalized maghemite fluid (DexMF) has been tested to treat Ehrlich-solid-tumor-bearing mice, evidencing its potential use in mediating magnetohyperthermia in breast cancer treatment. However, although magnetic nanoparticles tend to accumulate in tumor tissues, part of the nanomaterial can reach the blood stream, and then the organism. The aim of this study was to investigate the acute systemic effects of the intratumoral injection of DexMF mediating magnetohyperthermia in the treatment of an advanced clinical Ehrlich-solid-tumor, assessed through histopathological analyses of liver, kidneys, heart and spleen, comet assay, micronucleus test, hemogram, and serum levels of bilirubin, aspartate aminotransferase, alanine aminotransferase, gamma glutamyl transferase, alkaline phosphatase, creatinine, and urea. The tumor's histopathology and morphometry were used to assess its aggressiveness and regression. DexMF mediating hyperthermia was effective in containing tumor aggressiveness and in inducing tumor regression, besides showing no toxic effects. Its physical characteristics also suggest that it is safe to use in other biomedical applications.

  6. BdorOBP83a-2 Mediates Responses of the Oriental Fruit Fly to Semiochemicals

    Science.gov (United States)

    Wu, Zhongzhen; Lin, Jintian; Zhang, He; Zeng, Xinnian

    2016-01-01

    The oriental fruit fly, Bactrocera dorsalis (Diptera: Tephritidae), is one of the most destructive pests throughout tropical and subtropical regions in Asia. This insect displays remarkable changes during different developmental phases in olfactory behavior between sexually immature and mated adults. The olfactory behavioral changes provide clues to examine physiological and molecular bases of olfactory perception in this insect. We comparatively analyzed behavioral and neuronal responses of B. dorsalis adults to attractant semiochemicals, and the expression profiles of antenna chemosensory genes. We found that some odorant-binding proteins (OBPs) were upregulated in mated adults in association with their behavioral and neuronal responses. Ligand-binding assays further showed that one of OBP83a orthologs, BdorOBP83a-2, binds with high affinity to attractant semiochemicals. Functional analyses confirmed that the reduction in BdorOBP83a-2 transcript abundance led to a decrease in neuronal and behavioral responses to selected attractants. This study suggests that BdorOBP83a-2 mediates behavioral responses to attractant semiochemicals and could be a potential efficient target for pest control. PMID:27761116

  7. BdorOBP83a-2 mediates responses of the oriental fruit fly to semiochemicals

    Directory of Open Access Journals (Sweden)

    Zhongzhen Wu

    2016-10-01

    Full Text Available The oriental fruit fly, Bactrocera dorsalis (Diptera: Tephritidae, is one of the most destructive pests throughout tropical and subtropical regions in Asia. This insect displays remarkable changes during different developmental phases in olfactory behavior between sexually immature and mated adults. The olfactory behavioral changes provide clues to examine physiological and molecular bases of olfactory perception in this insect. We comparatively analyzed behavioral and neuronal responses of B. dorsalis adults to attractant semiochemicals, and the expression profiles of antenna chemosensory genes. We found that some odorant-binding proteins (OBPs were upregulated in mated adults in association with their behavioral and neuronal responses. Ligand-binding assays further showed that one of OBP83a orthologues, BdorOBP83a-2, binds with high affinity to attractant semiochemicals. Functional analyses confirmed that the reduction in BdorOBP83a-2 transcript abundance led to a decrease in neuronal and behavioral responses to selected attractants. This study suggests that BdorOBP83a-2 mediates behavioral responses to attractant semiochemicals and could be a potential efficient target for pest control.

  8. Targeting vascular NADPH oxidase 1 blocks tumor angiogenesis through a PPARα mediated mechanism.

    Science.gov (United States)

    Garrido-Urbani, Sarah; Jemelin, Stephane; Deffert, Christine; Carnesecchi, Stéphanie; Basset, Olivier; Szyndralewiez, Cédric; Heitz, Freddy; Page, Patrick; Montet, Xavier; Michalik, Liliane; Arbiser, Jack; Rüegg, Curzio; Krause, Karl Heinz; Imhof, Beat A; Imhof, Beat

    2011-02-07

    Reactive oxygen species, ROS, are regulators of endothelial cell migration, proliferation and survival, events critically involved in angiogenesis. Different isoforms of ROS-generating NOX enzymes are expressed in the vasculature and provide distinct signaling cues through differential localization and activation. We show that mice deficient in NOX1, but not NOX2 or NOX4, have impaired angiogenesis. NOX1 expression and activity is increased in primary mouse and human endothelial cells upon angiogenic stimulation. NOX1 silencing decreases endothelial cell migration and tube-like structure formation, through the inhibition of PPARα, a regulator of NF-κB. Administration of a novel NOX-specific inhibitor reduced angiogenesis and tumor growth in vivo in a PPARα dependent manner. In conclusion, vascular NOX1 is a critical mediator of angiogenesis and an attractive target for anti-angiogenic therapies.

  9. Targeting vascular NADPH oxidase 1 blocks tumor angiogenesis through a PPARα mediated mechanism.

    Directory of Open Access Journals (Sweden)

    Sarah Garrido-Urbani

    Full Text Available Reactive oxygen species, ROS, are regulators of endothelial cell migration, proliferation and survival, events critically involved in angiogenesis. Different isoforms of ROS-generating NOX enzymes are expressed in the vasculature and provide distinct signaling cues through differential localization and activation. We show that mice deficient in NOX1, but not NOX2 or NOX4, have impaired angiogenesis. NOX1 expression and activity is increased in primary mouse and human endothelial cells upon angiogenic stimulation. NOX1 silencing decreases endothelial cell migration and tube-like structure formation, through the inhibition of PPARα, a regulator of NF-κB. Administration of a novel NOX-specific inhibitor reduced angiogenesis and tumor growth in vivo in a PPARα dependent manner. In conclusion, vascular NOX1 is a critical mediator of angiogenesis and an attractive target for anti-angiogenic therapies.

  10. Role of Eosinophils and Tumor Necrosis Factor Alpha in Interleukin-25-Mediated Protection from Amebic Colitis

    Science.gov (United States)

    Noor, Zannatun; Watanabe, Koji; Abhyankar, Mayuresh M.; Burgess, Stacey L.; Buonomo, Erica L.

    2017-01-01

    ABSTRACT The parasite Entamoeba histolytica is a cause of diarrhea in infants in low-income countries. Previously, it was shown that tumor necrosis factor alpha (TNF-α) production was associated with increased risk of E. histolytica diarrhea in children. Interleukin-25 (IL-25) is a cytokine that is produced by intestinal epithelial cells that has a role in maintenance of gut barrier function and inhibition of TNF-α production. IL-25 expression was decreased in humans and in the mouse model of amebic colitis. Repletion of IL-25 blocked E. histolytica infection and barrier disruption in mice, increased gut eosinophils, and suppressed colonic TNF-α. Depletion of eosinophils with anti-Siglec-F antibody prevented IL-25-mediated protection. In contrast, depletion of TNF-α resulted in resistance to amebic infection. We concluded that IL-25 provides protection from amebiasis, which is dependent upon intestinal eosinophils and suppression of TNF-α. PMID:28246365

  11. Role of Eosinophils and Tumor Necrosis Factor Alpha in Interleukin-25-Mediated Protection from Amebic Colitis

    Directory of Open Access Journals (Sweden)

    Zannatun Noor

    2017-02-01

    Full Text Available The parasite Entamoeba histolytica is a cause of diarrhea in infants in low-income countries. Previously, it was shown that tumor necrosis factor alpha (TNF-α production was associated with increased risk of E. histolytica diarrhea in children. Interleukin-25 (IL-25 is a cytokine that is produced by intestinal epithelial cells that has a role in maintenance of gut barrier function and inhibition of TNF-α production. IL-25 expression was decreased in humans and in the mouse model of amebic colitis. Repletion of IL-25 blocked E. histolytica infection and barrier disruption in mice, increased gut eosinophils, and suppressed colonic TNF-α. Depletion of eosinophils with anti-Siglec-F antibody prevented IL-25-mediated protection. In contrast, depletion of TNF-α resulted in resistance to amebic infection. We concluded that IL-25 provides protection from amebiasis, which is dependent upon intestinal eosinophils and suppression of TNF-α.

  12. Sophoridinol derivative 05D induces tumor cells apoptosis by topoisomerase1-mediated DNA breakage

    Directory of Open Access Journals (Sweden)

    Zhao W

    2016-05-01

    Full Text Available Wuli Zhao, Caixia Zhang, Chongwen Bi, Cheng Ye, Danqing Song, Xiujun Liu, Rongguang Shao Key Laboratory of Antibiotic Bioengineering, Ministry of Health, Laboratory of Oncology, Institute of Medicinal Biotechnology, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, People’s Republic of China Abstract: Sophoridine is a quinolizidine natural product of Sophora alopecuroides and has been applied for treatment of malignant trophoblastic tumors. Although characterized by low toxicity, the limited-spectrum antitumor activity hinders its further applications. 05D, a derivative of sophoridine, exhibits a better anticancer activity on diverse cancer cells, including solid tumors, and hematologic malignancy. It could inhibit topoisomerase 1 (top1 activity by stabilizing DNA–top1 complex and induce mitochondria-mediated apoptosis by promoting DNA single- and double-strand breakage mediated by top1. Also, 05D induced HCT116 cells arrest at G1 phase by inactivating CDK2/CDK4–Rb–E2F and cyclinD1–CDK4–p21 checkpoint signal pathways. 05D suppressed the ataxia telangiectasia mutated (ATM and ATM and Rad3-related (ATR activation and decreased 53BP level, which contributed to DNA damage repair, suggesting that the novel compound 05D might be helpful to improve the antitumor activity of DNA damaging agent by repressing ATM and ATR activation and 53BP level. In addition, the priorities in molecular traits and druggability, such as a simple structure and formulation for oral administration, further prove 05D to be a promising targeting topoisomerase agent. Keywords: topoisomerase inhibitor, topoisomerase 1, DNA breakage, sophoridinol, anticancer, apoptosis, cell cycle

  13. Overcoming photodynamic resistance and tumor targeting dual-therapy mediated by indocyanine green conjugated gold nanospheres.

    Science.gov (United States)

    Li, Wei; Guo, Xiaomeng; Kong, Fenfen; Zhang, Hanbo; Luo, Lihua; Li, Qingpo; Zhu, Chunqi; Yang, Jie; Du, Yongzhong; You, Jian

    2017-07-28

    Photodynamic therapy (PDT) and photothermal therapy (PTT) have captured much attention due to the great potential to cure malignant tumor. Nevertheless, photodynamic resistance of cancer cells has limited the further efficacy of PDT. Unfortunately, the resistance mechanism and efforts to overcome the resistance still have been rarely reported so far. Here, we report a nanosystem with specific tumor targeting for combined PDT and PTT mediated by near-infrared (NIR) light, which was established by covalently conjugating indocyanine green (ICG) and TNYL peptide onto the surface of hollow gold nanospheres (HAuNS). Our nanosystem (TNYL-ICG-HAuNS) was proved to possess significantly increased light stability, reactive oxygen species (ROS) production and photothermal effect under NIR light irradiation, thus presenting a remarkably enhanced antitumor efficacy. The up-regulation of nuclear factor erythroid 2-related factor 2 (NFE2L2, Nrf2) in cancer cells during PDT induced a significant increase of ABCG2, NQO-1 and HIF-1α expression, causing PDT resistance of the cells. Interestingly, ABCG2 expression could almost keep a normal level in the whole PDT process mediated by TNYL-ICG-HAuNS. After repeated irradiations, TNYL-ICG-HAuNS could still produce almost constant ROS in cells while the Nrf2 expression reduced significantly. Furthermore, PDT resistance induced an obvious decrease of the internalization of free ICG, but didn't influence the cell uptake of TNYL-ICG-HAuNS. Our data explained that TNYL-ICG-HAuNS could overcome the photodynamic resistance of cancer cells, acting as a promising modality for simultaneous photothermal and photodynamic cancer therapy. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. The potential role of COX-2 in cancer stem cell-mediated canine mammary tumor initiation: an immunohistochemical study.

    Science.gov (United States)

    Huang, Jian; Zhang, Di; Xie, Fuqiang; Lin, Degui

    2015-01-01

    Increasing evidence suggests that cancer stem cells (CSCs) are responsible for tumor initiation and maintenance. Additionally, it is becoming apparent that cyclooxygenase (COX) signaling is associated with canine mammary tumor development. The goals of the present study were to investigate COX-2 expression patterns and their effect on CSC-mediated tumor initiation in primary canine mammary tissues and tumorsphere models using immunohistochemistry. Patterns of COX-2, CD44, octamer-binding transcription factor (Oct)-3/4, and epidermal growth factor receptor (EGFR) expression were examined in malignant mammary tumor (MMT) samples and analyzed in terms of clinicopathological characteristics. COX-2 and Oct-3/4 expression was higher in MMTs compared to other histological samples with heterogeneous patterns. In MMTs, COX-2 expression correlated with tumor malignancy features. Significant associations between COX-2, CD44, and EGFR were observed in low-differentiated MMTs. Comparative analysis showed that the levels of COX-2, CD44, and Oct-3/4 expression varied significantly among TSs of three histological grades. Enhanced COX-2 staining was consistently observed in TSs. Similar levels of staining intensity were found for CD44 and Oct-3/4, but EGFR expression was weak. Our findings indicate the potential role of COX-2 in CSC-mediated tumor initiation, and suggest that COX-2 inhibition may help treat canine mammary tumors by targeting CSCs.

  15. Capsaicin-mediated denervation of sensory neurons promotes mammary tumor metastasis to lung and heart.

    Science.gov (United States)

    Erin, Nuray; Boyer, Philip J; Bonneau, Robert H; Clawson, Gary A; Welch, Danny R

    2004-01-01

    Capsaicin specifically activates or destroys small diameter nociceptive sensory neurons that contain the capsaicin receptor, also called vanilloid receptor 1. Neurons sensitive to capsaicin mediate inflammatory pain and are important targets for management of chronic pain. These neurons also regulate local tissue homeostasis, inflammation, healing and development, especially under conditions of psychological stress. Stress contributes to increased cancer recurrence and metastasis through as yet undefined mechanisms. Likewise, activity of capsaicin-sensitive neurons is altered by pathological conditions that may lead to metastatic growth (e.g. stress). Therefore, we examined effects of a treatment that induces sensory nerve denervation on breast cancer metastases. Systemic denervation of sensory neurons caused by treatment with 125 mg/kg capsaicin resulted in significantly more lung and cardiac metastases in adult mice injected orthotopically with syngeneic 4T1 mammary carcinoma cells than was observed in vehicle-treated controls. Heart metastases, normally very rare, occurred as pericardial nodules, intra-myocardial nodules, or combined pericardial-myocardial lesions. Since the rate of primary tumor growth was unaffected, effects on metastases appear to be host tissue-specific. Although preliminary, these observations provide one possible explanation for resistance of cardiac tissue to tumor involvement and highlight contributions of host tissue, including sensory neurons, in the efficiency of cancer metastasis.

  16. PLGA Nanoparticles for Ultrasound-Mediated Gene Delivery to Solid Tumors

    Directory of Open Access Journals (Sweden)

    Marxa Figueiredo

    2012-01-01

    Full Text Available This paper focuses on novel approaches in the field of nanotechnology-based carriers utilizing ultrasound stimuli as a means to spatially target gene delivery in vivo, using nanoparticles made with either poly(lactic-co-glycolic acid (PLGA or other polymers. We specifically discuss the potential for gene delivery by particles that are echogenic (amenable to destruction by ultrasound composed either of polymers (PLGA, polystyrene or other contrast agent materials (Optison, SonoVue microbubbles. The use of ultrasound is an efficient tool to further enhance gene delivery by PLGA or other echogenic particles in vivo. Echogenic PLGA nanoparticles are an attractive strategy for ultrasound-mediated gene delivery since this polymer is currently approved by the US Food and Drug Administration for drug delivery and diagnostics in cancer, cardiovascular disease, and also other applications such as vaccines and tissue engineering. This paper will review recent successes and the potential of applying PLGA nanoparticles for gene delivery, which include (a echogenic PLGA used with ultrasound to enhance local gene delivery in tumors or muscle and (b PLGA nanoparticles currently under development, which could benefit in the future from ultrasound-enhanced tumor targeted gene delivery.

  17. Newcomers to the WW Domain-Mediated Network of the Hippo Tumor Suppressor Pathway.

    Science.gov (United States)

    Sudol, Marius

    2010-11-01

    The Hippo tumor suppressor pathway regulates the size of organs by controlling 2 opposing processes: proliferation and apoptosis. The pathway was originally defined in Drosophila, but it is well conserved in mammals. One of the unique features of Hippo signaling is the unusually wide occurrence of WW domains and its cognate PPxY ligand motifs within components of this pathway. Recently, it was proposed that the prevalence of WW domain-mediated complexes in the Hippo signaling pathway should facilitate its molecular analysis and help in the identification of new components of the Hippo-centered network. Indeed, several new members of the Hippo pathway, which form functional complexes with WW domains of YAP and TAZ effectors, were recently described. We focus here on 2 families of such proteins, angiomotins and SMADs, plus 1 regulatory factor, WBP-2, which together shed new light on the rapidly expanding Hippo network. Since the Hippo pathway acts as a tumor suppressor pathway, the complexes described here, which assemble on WW domains of YAP and TAZ, represent potential targets of cancer therapy.

  18. SDF-1α mediates wound-promoted tumor growth in a syngeneic orthotopic mouse model of breast cancer.

    Directory of Open Access Journals (Sweden)

    Christina H Stuelten

    Full Text Available Increased growth of residual tumors in the proximity of acute surgical wounds has been reported; however, the mechanisms of wound-promoted tumor growth remain unknown. Here, we used a syngeneic, orthotopic mouse model of breast cancer to study mechanisms of wound-promoted tumor growth. Our results demonstrate that exposure of metastatic mouse breast cancer cells (4T1 to SDF-1α, which is increased in wound fluid, results in increased tumor growth. Both, wounding and exposure of 4T1 cells to SDF-1α not only increased tumor growth, but also tumor cell proliferation rate and stromal collagen deposition. Conversely, systemic inhibition of SDF-1α signaling with the small molecule AMD 3100 abolished the effect of wounding, and decreased cell proliferation, collagen deposition, and neoangiogenesis to the levels observed in control animals. Furthermore, using different mouse strains we could demonstrate that the effect of wounding on tumor growth and SDF-1α levels is host dependent and varies between mouse strains. Our results show that wound-promoted tumor growth is mediated by elevated SDF-1α levels and indicate that the effect of acute wounds on tumor growth depends on the predetermined wound response of the host background and its predetermined wound response.

  19. Ultrasound-mediated tumor imaging and nanotherapy using drug loaded, block copolymer stabilized perfluorocarbon nanoemulsions.

    Science.gov (United States)

    Rapoport, Natalya; Nam, Kweon-Ho; Gupta, Roohi; Gao, Zhongao; Mohan, Praveena; Payne, Allison; Todd, Nick; Liu, Xin; Kim, Taeho; Shea, Jill; Scaife, Courtney; Parker, Dennis L; Jeong, Eun-Kee; Kennedy, Anne M

    2011-07-15

    Perfluorocarbon nanoemulsions can deliver lipophilic therapeutic agents to solid tumors and simultaneously provide for monitoring nanocarrier biodistribution via ultrasonography and/or (19)F MRI. In the first generation of block copolymer stabilized perfluorocarbon nanoemulsions, perfluoropentane (PFP) was used as the droplet forming compound. Although manifesting excellent therapeutic and ultrasound imaging properties, PFP nanoemulsions were unstable at storage, difficult to handle, and underwent hard to control phenomenon of irreversible droplet-to-bubble transition upon injection. To solve the above problems, perfluoro-15-crown-5-ether (PFCE) was used as a core forming compound in the second generation of block copolymer stabilized perfluorocarbon nanoemulsions. PFCE nanodroplets manifest both ultrasound and fluorine ((19)F) MR contrast properties, which allows using multimodal imaging and (19)F MR spectroscopy for monitoring nanodroplet pharmacokinetics and biodistribution. In the present paper, acoustic, imaging, and therapeutic properties of unloaded and paclitaxel (PTX) loaded PFCE nanoemulsions are reported. As manifested by the (19)F MR spectroscopy, PFCE nanodroplets are long circulating, with about 50% of the injected dose remaining in circulation 2h after the systemic injection. Sonication with 1-MHz therapeutic ultrasound triggered reversible droplet-to-bubble transition in PFCE nanoemulsions. Microbubbles formed by acoustic vaporization of nanodroplets underwent stable cavitation. The nanodroplet size (200nm to 350nm depending on a type of the shell and conditions of emulsification) as well as long residence in circulation favored their passive accumulation in tumor tissue that was confirmed by ultrasonography. In the breast and pancreatic cancer animal models, ultrasound-mediated therapy with paclitaxel-loaded PFCE nanoemulsions showed excellent therapeutic properties characterized by tumor regression and suppression of metastasis. Anticipated

  20. Luteolin inhibits human prostate tumor growth by suppressing vascular endothelial growth factor receptor 2-mediated angiogenesis.

    Directory of Open Access Journals (Sweden)

    Poyil Pratheeshkumar

    Full Text Available Angiogenesis, the formation of new blood vessels from pre-existing vascular beds, is essential for tumor growth, invasion, and metastasis. Luteolin is a common dietary flavonoid found in fruits and vegetables. We studied the antiangiogenic activity of luteolin using in vitro, ex vivo, and in vivo models. In vitro studies using rat aortic ring assay showed that luteolin at non-toxic concentrations significantly inhibited microvessel sprouting and proliferation, migration, invasion and tube formation of endothelial cells, which are key events in the process of angiogenesis. Luteolin also inhibited ex vivo angiogenesis as revealed by chicken egg chorioallantoic membrane assay (CAM and matrigel plug assay. Gelatin zymographic analysis demonstrated the inhibitory effect of luteolin on the activation of matrix metalloproteinases MMP-2 and MMP-9. Western blot analysis showed that luteolin suppressed VEGF induced phosphorylation of VEGF receptor 2 and their downstream protein kinases AKT, ERK, mTOR, P70S6K, MMP-2, and MMP-9 in HUVECs. Proinflammatory cytokines such as IL-1β, IL-6, IL-8, and TNF-α level were significantly reduced by the treatment of luteolin in PC-3 cells. Luteolin (10 mg/kg/d significantly reduced the volume and the weight of solid tumors in prostate xenograft mouse model, indicating that luteolin inhibited tumorigenesis by targeting angiogenesis. CD31 and CD34 immunohistochemical staining further revealed that the microvessel density could be remarkably suppressed by luteolin. Moreover, luteolin reduced cell viability and induced apoptosis in prostate cancer cells, which were correlated with the downregulation of AKT, ERK, mTOR, P70S6K, MMP-2, and MMP-9 expressions. Taken together, our findings demonstrate that luteolin inhibits human prostate tumor growth by suppressing vascular endothelial growth factor receptor 2-mediated angiogenesis.

  1. Tumor

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    2008479 Preliminary study of MR elastography in brain tumors. XU Lei(徐磊), et al.Neurosci Imaging Center, Beijing Tiantan Hosp, Capital Med Univ, Beijing 100050.Chin J Radiol 2008;42(6):605-608. Objective To investigate the potential values of magnetic resonance elastography (MRE) for evaluating the brain tumor consistency in vivo. Methods Fourteen patients with known solid brain tumor (5 male, 9 female; age range: 16-63 years)

  2. A secretory phospholipase A2-mediated neuroprotection and anti-apoptosis

    Directory of Open Access Journals (Sweden)

    Howells David W

    2009-09-01

    Full Text Available Abstract Background Phospholipase A2 liberates free fatty acids and lysophospholipids upon hydrolysis of phospholipids and these products are often associated with detrimental effects such as inflammation and cerebral ischemia. The neuroprotective effect of neutral phospholipase from snake venom has been investigated. Results A neutral anticoagulant secretory phospholipase A2 (nPLA from the venom of Naja sputatrix (Malayan spitting cobra has been found to reduce infarct volume in rats subjected to focal transient cerebral ischemia and to alleviate the neuronal damage in organotypic hippocampal slices subjected to oxygen-glucose deprivation (OGD. Real-time PCR based gene expression analysis showed that anti-apoptotic and pro-survival genes have been up-regulated in both in vivo and in vitro models. Staurosporine or OGD mediated apoptotic cell death in astrocytoma cells has also been found to be reduced by nPLA with a corresponding reduction in caspase 3 activity. Conclusion We have found that a secretory phospholipase (nPLA purified from snake venom could reduce infarct volume in rodent stroke model. nPLA, has also been found to reduce neuronal cell death, apoptosis and promote cell survival in vitro ischemic conditions. In all conditions, the protective effects could be seen at sub-lethal concentrations of the protein.

  3. SLC45A2: A Melanoma Antigen with High Tumor Selectivity and Reduced Potential for Autoimmune Toxicity.

    Science.gov (United States)

    Park, Jungsun; Talukder, Amjad H; Lim, Seon A; Kim, Kwanghee; Pan, Ke; Melendez, Brenda; Bradley, Sherille D; Jackson, Kyle R; Khalili, Jahan S; Wang, Junmei; Creasy, Caitlin; Pan, Bih-Fang; Woodman, Scott E; Bernatchez, Chantale; Hawke, David; Hwu, Patrick; Lee, Kyung-Mi; Roszik, Jason; Lizée, Gregory; Yee, Cassian

    2017-08-01

    Cytotoxic T lymphocyte (CTL)-based immunotherapies have had remarkable success at generating objective clinical responses in patients with advanced metastatic melanoma. Although the melanocyte differentiation antigens (MDA) MART-1, PMEL, and tyrosinase were among the first melanoma tumor-associated antigens identified and targeted with immunotherapy, expression within normal melanocytes of the eye and inner ear can elicit serious autoimmune side effects, thus limiting their clinical potential as CTL targets. Using a tandem mass spectrometry (MS) approach to analyze the immunopeptidomes of 55 melanoma patient-derived cell lines, we identified a number of shared HLA class I-bound peptides derived from the melanocyte-specific transporter protein SLC45A2. Antigen-specific CTLs generated against HLA-A*0201- and HLA-A*2402-restricted SLC45A2 peptides effectively killed a majority of HLA-matched cutaneous, uveal, and mucosal melanoma cell lines tested (18/25). CTLs specific for SLC45A2 showed significantly reduced recognition of HLA-matched primary melanocytes that were, conversely, robustly killed by MART1- and PMEL-specific T cells. Transcriptome analysis revealed that SLC45A2 mRNA expression in normal melanocytes was less than 2% that of other MDAs, therefore providing a more favorable melanoma-to-melanocyte expression ratio. Expression of SLC45A2 and CTL sensitivity could be further upregulated in BRAF(V600E)-mutant melanoma cells upon treatment with BRAF or MEK inhibitors, similarly to other MDAs. Taken together, our study demonstrates the feasibility of using tandem MS as a means of discovering shared immunogenic tumor-associated epitopes and identifies SLC45A2 as a promising immunotherapeutic target for melanoma with high tumor selectivity and reduced potential for autoimmune toxicity. Cancer Immunol Res; 5(8); 618-29. ©2017 AACR. ©2017 American Association for Cancer Research.

  4. Cytosolic phospholipase A(2) alpha mediates electrophysiologic responses of hippocampal pyramidal neurons to neurotoxic NMDA treatment.

    Science.gov (United States)

    Shen, Ying; Kishimoto, Koji; Linden, David J; Sapirstein, Adam

    2007-04-03

    The arachidonic acid-generating enzyme cytosolic phospholipase A(2) alpha (cPLA(2)alpha) has been implicated in the progression of excitotoxic neuronal injury. However, the mechanisms of cPLA(2)alpha toxicity have yet to be determined. Here, we used a model system exposing mouse hippocampal slices to NMDA as an excitotoxic injury, in combination with simultaneous patch-clamp recording and confocal Ca(2+) imaging of CA1 pyramidal neurons. NMDA treatment caused significantly greater injury in wild-type (WT) than in cPLA(2)alpha null CA1 neurons. Bath application of NMDA evoked a slow inward current in voltage-clamped neurons (composed of both NMDA receptor-mediated and other conductances) that was smaller in cPLA(2)alpha null than in WT slices. This was not due to down-regulation of NMDA receptor function because NMDA receptor-mediated currents were equivalent in each genotype following brief photolysis of caged glutamate. Current-clamp recordings were made during and following NMDA exposure by eliciting a single action potential with a brief current injection. After NMDA exposure, WT CA1 neurons developed a spike-evoked plateau potential and an increased spike-evoked dendritic Ca(2+) transient. These effects were absent in CA1 neurons from cPLA(2)alpha null mice and WT neurons treated with a cPLA(2)alpha inhibitor. The Ca-sensitive K-channel toxins, apamin and paxilline, caused spike broadening and Ca(2+) enhancement in WT and cPLA(2)alpha null slices. NMDA application in WT and arachidonate applied to cPLA(2)alpha null cells occluded the effects of apamin/paxilline. These results indicate that cPLA(2)alpha activity is required for development of aberrant electrophysiologic events triggered by NMDA receptor activation, in part through attenuation of K-channel function.

  5. Near-infrared fluorescence heptamethine carbocyanine dyes mediate imaging and targeted drug delivery for human brain tumor.

    Science.gov (United States)

    Wu, Jason Boyang; Shi, Changhong; Chu, Gina Chia-Yi; Xu, Qijin; Zhang, Yi; Li, Qinlong; Yu, John S; Zhau, Haiyen E; Chung, Leland W K

    2015-10-01

    Brain tumors and brain metastases are among the deadliest malignancies of all human cancers, largely due to the cellular blood-brain and blood-tumor barriers that limit the delivery of imaging and therapeutic agents from the systemic circulation to tumors. Thus, improved strategies for brain tumor visualization and targeted treatment are critically needed. Here we identified and synthesized a group of near-infrared fluorescence (NIRF) heptamethine carbocyanine dyes and derivative NIRF dye-drug conjugates for effective imaging and therapeutic targeting of brain tumors of either primary or metastatic origin in mice, which is mechanistically mediated by tumor hypoxia and organic anion-transporting polypeptide genes. We also demonstrate that these dyes, when conjugated to chemotherapeutic agents such as gemcitabine, significantly restricted the growth of both intracranial glioma xenografts and prostate tumor brain metastases and prolonged survival in mice. These results show promise in the application of NIRF dyes as novel theranostic agents for the detection and treatment of brain tumors.

  6. Near-infrared fluorescence heptamethine carbocyanine dyes mediate imaging and targeted drug delivery for human brain tumor

    Science.gov (United States)

    Wu, Jason Boyang; Shi, Changhong; Chu, Gina Chia-Yi; Xu, Qijin; Zhang, Yi; Li, Qinlong; Yu, John S.; Zhau, Haiyen E.; Chung, Leland W.K.

    2016-01-01

    Brain tumors and brain metastases are among the deadliest malignancies of all human cancers, largely due to the cellular blood-brain and blood-tumor barriers that limit the delivery of imaging and therapeutic agents from the systemic circulation to tumors. Thus, improved strategies for brain tumor visualization and targeted treatment are critically needed. Here we identified and synthesized a group of near-infrared fluorescence (NIRF) heptamethine carbocyanine dyes and derivative NIRF dye-drug conjugates for effective imaging and therapeutic targeting of brain tumors of either primary or metastatic origin in mice, which is mechanistically mediated by tumor hypoxia and organic aniontransporting polypeptide genes. We also demonstrate that these dyes, when conjugated to chemotherapeutic agents such as gemcitabine, significantly restricted the growth of both intracranial glioma xenografts and prostate tumor brain metastases and prolonged survival in mice. These results show promise in the application of NIRF dyes as novel theranostic agents for the detection and treatment of brain tumors. PMID:26197410

  7. Caloric restriction maintains OX40 agonist-mediated tumor immunity and CD4 T cell priming during aging.

    Science.gov (United States)

    Farazi, Michelle; Nguyen, Justine; Goldufsky, Josef; Linnane, Stephanie; Lukaesko, Lisa; Weinberg, Andrew D; Ruby, Carl E

    2014-06-01

    Immune responses wane during aging, posing challenges to the potential effectiveness of cancer immunotherapies. We previously demonstrated that in the context of a promising immunotherapeutic, OX40 agonist (αOX40), older animals exhibited impaired anti-tumor immune responses and diminished CD4 T cell effector differentiation. In this study, we hypothesized that tumor immune responses could be maintained during aging through caloric restriction (CR) or dietary supplementation with resveratrol (RES), a CR mimetic. Mice were placed on either a calorically restricted diet or a RES-formulated diet starting between 4 and 6 months of age and continued until mice reached 12 months of age. Tumor immune responses were assessed after challenging with either sarcoma or breast tumor cells followed by αOX40 treatment. Our results show that CR, but not RES, maintained OX40-mediated anti-tumor immunity. In addition, CR fully sustained antigen-specific CD4 T cell priming in aged hosts (12 months old), whereas tumor-specific CD8 T cell priming was not fully maintained compared to young reference animals (2 months old). Thus, CR appears to maintain immunological fitness of the CD4 T cell priming environment during aging, which is critical for optimal OX40-mediated responses.

  8. Accumulation of Phase-Shift Nanoemulsions to Enhance MR-Guided Ultrasound-Mediated Tumor Ablation In Vivo

    Directory of Open Access Journals (Sweden)

    Jonathan A. Kopechek

    2013-01-01

    Full Text Available Magnetic resonance-guided high intensity focused ultrasound (MRgHIFU is being explored as a non-invasive technology to treat solid tumors. However, the clinical use of HIFU for tumor ablation applications is currently limited by the long treatment times required. Phase-shift nanoemulsions (PSNE, consisting of liquid perfluorocarbon droplets that can be vaporized into microbubbles, are being developed to accelerate HIFU-mediated heating. The purpose of this study was to examine accumulation of PSNE in intramuscular rabbit tumors in vivo. MR images were acquired before and after intravenous injection of gadolinium-containing PSNE. MR signal enhancement was observed in rabbit tumors up to six hours after injection, indicating that PSNE accumulated in the tumors. In addition, PSNE vaporization was detected in the tumor with B-mode ultrasound imaging, and MR thermometry measurements indicated that PSNE accelerated the rate of HIFU-mediated heating. These results suggest that PSNE could dramatically improve the efficiency and clinical feasibility of MRgHIFU.

  9. Tumor penetrability and anti-angiogenesis using iRGD-mediated delivery of doxorubicin-polymer conjugates.

    Science.gov (United States)

    Wang, Ke; Zhang, Xiaofeng; Liu, Yang; Liu, Chang; Jiang, Baohong; Jiang, Yanyan

    2014-10-01

    Tumor-penetrating peptide, iRGD (internalizing RGD, CRGDK/RGPD/EC) with the similar affinity to αv integrins as conventional RGD cyclopeptide could enhance the tumor penetrability of drugs by binding to neuropilin-1 (NRP-1) that over-expressed on both angiogenic blood vessels and tumor cells. Comparing with our previous study, in which a RGD cyclopeptide (RGDyC) was bound to PEGylated polyamidoamine (PAMAM) dendrimer with doxorubicin (DOX) by acid-sensitive cis-aconityl linkage (PEG-PAMAM-cis-aconityl-DOX, PPCD), the present study selected iRGD instead of previous RGD to produce iRGD-PPCD conjugate. The effect of iRGD-mediated PPCD on tumor penetration was compared with the conventional RGD ones via administration of RGDs-modified PPCD (iRGD/RGDs-PPCD) and co-administration of RGDs and PPCD (iRGD/RGD + PPCD). C6 cells were selected as the cell model owing to the highest expression of αv integrins and NRP-1 among four tumor cell lines. In vitro cytotoxicity and cellular uptake showed no significant difference between RGD-PPCD and iRGD-PPCD, but glioma spheroid penetration study showed that RGD-PPCD, iRGD-PPCD and iRGD + PPCD penetrated into C6 spheroids with a depth of 115 μm, 144 μm and 150 μm, respectively, indicating that the iRGD-mediated PPCD delivery system had a stronger penetrating ability than the RGD ones. In vivo results also demonstrated the superiority of iRGD system over RGD ones. After systemic administration, iRGD-mediated PPCD increased tumor vascular permeability, decreased tumor vascular density and average vascular diameter. Correspondingly, the iRGD system exhibited stronger penetration ability, higher accumulation in brain tumor. The median survival time of iRGD + PPCD, iRGD-PPCD and RGD-PPCD treatment groups were 61, 57.5 and 43.5 days. The present findings strongly suggested that the iRGD-mediated drug delivery system could significantly improve the efficacy of tumor therapy through enhancing tumor accumulation and penetration as

  10. Lactate is a mediator of metabolic cooperation between stromal carcinoma associated fibroblasts and glycolytic tumor cells in the tumor microenvironment

    Energy Technology Data Exchange (ETDEWEB)

    Rattigan, Yanique I.; Patel, Brijesh B. [Graduate School of Biomedical Sciences, The Cancer Institute of New Jersey, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, 195 Little Albany Street, New Brunswick, NJ 08901 (United States); Department of Pharmacology, The Cancer Institute of New Jersey, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, 195 Little Albany Street, New Brunswick, NJ 08901 (United States); Ackerstaff, Ellen [Department of Medical Physics, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States); Sukenick, George [Molecular Pharmacology and Chemistry Research Program, Sloan-Kettering Institute, 415 E 68th Street, New York, NY 10065 (United States); Koutcher, Jason A. [Department of Medical Physics, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States); Glod, John W. [Graduate School of Biomedical Sciences, The Cancer Institute of New Jersey, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, 195 Little Albany Street, New Brunswick, NJ 08901 (United States); Department of Pharmacology, The Cancer Institute of New Jersey, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, 195 Little Albany Street, New Brunswick, NJ 08901 (United States); Department of Pediatric Oncology, The Cancer Institute of New Jersey, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, 195 Little Albany Street, New Brunswick, NJ 08901 (United States); and others

    2012-02-15

    Human mesenchymal stem cells (hMSCs) are bone marrow-derived stromal cells, which play a role in tumor progression. We have shown earlier that breast cancer cells secrete higher levels of interleukin-6 (IL-6) under hypoxia, leading to the recruitment of hMSCs towards hypoxic tumor cells. We found that (i) MDA-MB-231 cells secrete significantly higher levels of lactate (3-fold more) under hypoxia (1% O{sub 2}) than under 20% O{sub 2} and (ii) lactate recruits hMSCs towards tumor cells by activating signaling pathways to enhance migration. The mRNA and protein expression of functional MCT1 in hMSCs is increased in response to lactate exposure. Thus, we hypothesized that hMSCs and stromal carcinoma associated fibroblasts (CAFs) in the tumor microenvironment have the capacity to take up lactate expelled from tumor cells and use it as a source of energy. Our {sup 13}C NMR spectroscopic measurements indicate that {sup 13}C-lactate is converted to {sup 13}C-alpha ketoglutarate in hMSCs and CAFs supporting this hypothesis. To our knowledge this is the first in vitro model system demonstrating that hMSCs and CAFs can utilize lactate produced by tumor cells.

  11. Lactate is a mediator of metabolic cooperation between stromal carcinoma associated fibroblasts and glycolytic tumor cells in the tumor microenvironment*

    Science.gov (United States)

    Rattigan, Yanique I.; Patel, Brijesh B.; Ackerstaff, Ellen; Sukenick, George; Koutcher, Jason A.; Glod, John W.; Banerjee, Debabrata

    2012-01-01

    Human mesenchymal stem cells (hMSCs) are bone marrow-derived stromal cells, which play a role in tumor progression. We have shown earlier that breast cancer cells secrete higher levels of interleukin-6 (IL-6) under hypoxia, leading to the recruitment of hMSCs towards hypoxic tumor cells. We found that (i) MDA-MB-231 cells secrete significantly higher levels of lactate (3-fold more) under hypoxia (1% O2) than under 20% O2 and (ii) lactate recruits hMSCs towards tumor cells by activating signaling pathways to enhance migration. The mRNA and protein expression of functional MCT1 in hMSCs is increased in response to lactate exposure. Thus, we hypothesized that hMSCs and stromal carcinoma associated fibroblasts (CAFs) in the tumor microenvironment have the capacity to take up lactate expelled from tumor cells and use it as a source of energy. Our 13C NMR spectroscopic measurements indicate that 13C-lactate is converted to 13C-alpha ketoglutarate in hMSCs and CAFs supporting this hypothesis. To our knowledge this is the first in vitro model system demonstrating that hMSCs and CAFs can utilize lactate produced by tumor cells. PMID:22178238

  12. Ultraslow Water-Mediated Transmembrane Interactions Regulate the Activation of A2A Adenosine Receptor.

    Science.gov (United States)

    Lee, Yoonji; Kim, Songmi; Choi, Sun; Hyeon, Changbong

    2016-09-20

    Water molecules inside a G-protein coupled receptor (GPCR) have recently been spotlighted in a series of crystal structures. To decipher the dynamics and functional roles of internal water molecules in GPCR activity, we studied the A2A adenosine receptor using microsecond molecular-dynamics simulations. Our study finds that the amount of water flux across the transmembrane (TM) domain varies depending on the receptor state, and that the water molecules of the TM channel in the active state flow three times more slowly than those in the inactive state. Depending on the location in solvent-protein interface as well as the receptor state, the average residence time of water in each residue varies from ∼O(10(2)) ps to ∼O(10(2)) ns. Especially, water molecules, exhibiting ultraslow relaxation (∼O(10(2)) ns) in the active state, are found around the microswitch residues that are considered activity hotspots for GPCR function. A continuous allosteric network spanning the TM domain, arising from water-mediated contacts, is unique in the active state, underscoring the importance of slow water molecules in the activation of GPCRs. Copyright © 2016 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  13. Myo9b is a key player in SLIT/ROBO-mediated lung tumor suppression.

    Science.gov (United States)

    Kong, Ruirui; Yi, Fengshuang; Wen, Pushuai; Liu, Jianghong; Chen, Xiaoping; Ren, Jinqi; Li, Xiaofei; Shang, Yulong; Nie, Yongzhan; Wu, Kaichun; Fan, Daiming; Zhu, Li; Feng, Wei; Wu, Jane Y

    2015-11-03

    Emerging evidence indicates that the neuronal guidance molecule SLIT plays a role in tumor suppression, as SLIT-encoding genes are inactivated in several types of cancer, including lung cancer; however, it is not clear how SLIT functions in lung cancer. Here, our data show that SLIT inhibits cancer cell migration by activating RhoA and that myosin 9b (Myo9b) is a ROBO-interacting protein that suppresses RhoA activity in lung cancer cells. Structural analyses revealed that the RhoGAP domain of Myo9b contains a unique patch that specifically recognizes RhoA. We also determined that the ROBO intracellular domain interacts with the Myo9b RhoGAP domain and inhibits its activity; therefore, SLIT-dependent activation of RhoA is mediated by ROBO inhibition of Myo9b. In a murine model, compared with control lung cancer cells, SLIT-expressing cells had a decreased capacity for tumor formation and lung metastasis. Evaluation of human lung cancer and adjacent nontumor tissues revealed that Myo9b is upregulated in the cancer tissue. Moreover, elevated Myo9b expression was associated with lung cancer progression and poor prognosis. Together, our data identify Myo9b as a key player in lung cancer and as a ROBO-interacting protein in what is, to the best of our knowledge, a newly defined SLIT/ROBO/Myo9b/RhoA signaling pathway that restricts lung cancer progression and metastasis. Additionally, our work suggests that targeting the SLIT/ROBO/Myo9b/RhoA pathway has potential as a diagnostic and therapeutic strategy for lung cancer.

  14. Molecular study on copper-mediated tumor proteasome inhibition and cell death.

    Science.gov (United States)

    Xiao, Yan; Chen, Di; Zhang, Xia; Cui, Qiuzhi; Fan, Yuhua; Bi, Caifeng; Dou, Q Ping

    2010-07-01

    The metal ion copper is a cofactor essential for maintaining normal biological and physical functions in human beings. High copper levels have been found in variety of tumor tissues and are involved in tumor angiogenesis processes. The ubiquitin-proteasome system plays an important role in cell growth and apoptosis and has been shown as a novel target for cancer therapy. We previously reported that some organic copper complexes can inhibit the proteasomal chymotrypsin-like activity and induce apoptosis in human cancer cells and xenograft models. In the current study, we investigated the effect of oxidation status of copper, Cu(I) or Cu(II), on inhibition of proteasome activity, induction of apoptosis, and induction of reactive oxygen species (ROS) in human cancer cells. We report four major findings here: i) both Cu(I) and Cu(II) could inhibit the chymotrypsin-like activity of purified 20S proteasome, but Cu(I) was more potent than Cu(II), ii) purified 20S proteasome protein was able to reduce Cu(II) to Cu(I), suggesting that Cu(I) is the oxidation status of copper that directly reacts with the proteasome, iii) when complexed with the copper ligand neocuproine, Cu(I) showed higher ability to induce ROS production in cancer cells, compared with Cu(II), iv) addition of a ROS scavenger in the cancer cell culture-blocked copper-induced ROS generation, but did not overcome copper-mediated proteasome-inhibitory and cell death-inducing events, demonstrating the ROS-independent proteasome-inhibitory property of copper complexes.

  15. Pharmacological inhibition of microsomal prostaglandin E synthase-1 suppresses epidermal growth factor receptor-mediated tumor growth and angiogenesis.

    Directory of Open Access Journals (Sweden)

    Federica Finetti

    Full Text Available BACKGROUND: Blockade of Prostaglandin (PG E(2 production via deletion of microsomal Prostaglandin E synthase-1 (mPGES-1 gene reduces tumor cell proliferation in vitro and in vivo on xenograft tumors. So far the therapeutic potential of the pharmacological inhibition of mPGES-1 has not been elucidated. PGE(2 promotes epithelial tumor progression via multiple signaling pathways including the epidermal growth factor receptor (EGFR signaling pathway. METHODOLOGY/PRINCIPAL FINDINGS: Here we evaluated the antitumor activity of AF3485, a compound of a novel family of human mPGES-1 inhibitors, in vitro and in vivo, in mice bearing human A431 xenografts overexpressing EGFR. Treatment of the human cell line A431 with interleukin-1beta (IL-1β increased mPGES-1 expression, PGE(2 production and induced EGFR phosphorylation, and vascular endothelial growth factor (VEGF and fibroblast growth factor-2 (FGF-2 expression. AF3485 reduced PGE(2 production, both in quiescent and in cells stimulated by IL-1β. AF3485 abolished IL-1β-induced activation of the EGFR, decreasing VEGF and FGF-2 expression, and tumor-mediated endothelial tube formation. In vivo, in A431 xenograft, AF3485, administered sub-chronically, decreased tumor growth, an effect related to inhibition of EGFR signalling, and to tumor microvessel rarefaction. In fact, we observed a decrease of EGFR phosphorylation, and VEGF and FGF-2 expression in tumours explanted from treated mice. CONCLUSION: Our work demonstrates that the pharmacological inhibition of mPGES-1 reduces squamous carcinoma growth by suppressing PGE(2 mediated-EGFR signalling and by impairing tumor associated angiogenesis. These results underscore the potential of mPGES-1 inhibitors as agents capable of controlling tumor growth.

  16. GLUT1-mediated selective tumor targeting with fluorine containing platinum(II) glycoconjugates.

    Science.gov (United States)

    Liu, Ran; Fu, Zheng; Zhao, Meng; Gao, Xiangqian; Li, Hong; Mi, Qian; Liu, Pengxing; Yang, Jinna; Yao, Zhi; Gao, Qingzhi

    2017-06-13

    Increased glycolysis and overexpression of glucose transporters (GLUTs) are physiological characteristics of human malignancies. Based on the so-called Warburg effect, 18flurodeoxyglucose-positron emission tomography (FDG-PET) has successfully developed as clinical modality for the diagnosis and staging of many cancers. To leverage this glucose transporter mediated metabolic disparity between normal and malignant cells, in the current report, we focus on the fluorine substituted series of glucose, mannose and galactose-conjugated (trans-R,R-cyclohexane-1,2-diamine)-2-flouromalonato-platinum(II) complexes for a comprehensive evaluation on their selective tumor targeting. Besides highly improved water solubility, these sugar-conjugates presented improved cytotoxicity than oxaliplatin in glucose tranporters (GLUTs) overexpressing cancer cell lines and exhibited no cross-resistance to cisplatin. For the highly water soluble glucose-conjugated complex (5a), two novel in vivo assessments were conducted and the results revealed that 5a was more efficacious at a lower equitoxic dose (70% MTD) than oxaliplatin (100% MTD) in HT29 xenograft model, and it was significantly more potent than oxaliplatin in leukemia-bearing DBA/2 mice as well even at equimolar dose levels (18% vs 90% MTD). GLUT inhibitor mediated cell viability analysis, GLUT1 knockdown cell line-based cytotoxicity evaluation, and platinum accumulation study demonstrated that the cellular uptake of the sugar-conjugates was regulated by GLUT1. The higher intrinsic DNA reactivity of the sugar-conjugates was confirmed by kinetic study of platinum(II)-guanosine adduct formation. The mechanistic origin of the antitumor effect of the fluorine complexes was found to be forming the bifunctional Pt-guanine-guanine (Pt-GG) intrastrand cross-links with DNA. The results provide a rationale for Warburg effect targeted anticancer drug design.

  17. Soluble factor from murine bladder tumor-2 cell elevates nitric oxide production in macrophages and enhances the taxol-mediated macrophage cytotoxicity on tumor cells.

    Science.gov (United States)

    Choi, Suck-Chei; Oh, Hyun-Mee; Park, Jae-Sung; Han, Weon-Cheol; Yoon, Kwon-Ha; Kim, Tae-Hyeon; Yun, Ki-Jung; Kim, Eun-Cheol; Nah, Yong-Ho; Cha, Young-Nam; Chung, Hun-Taeg; Jun, Chang-Duk

    2003-01-01

    The therapeutic mechanism of taxol is believed to reside primarily in its ability to stabilize microtubules and prevent cell progression through mitosis. Taxol also can activate macrophage-mediated antitumor mechanism through a nitric oxide (NO)-dependent pathway. To address whether any mechanisms account for superficial urinary bladder tumor cell killing, we evaluated the effects of taxol on the growth and viability of murine bladder tumor-2 (MBT-2) cells in vitro, both in the absence and presence of murine macrophages. In addition, we evaluated whether a soluble factor generated from MBT-2 cells could modulate the antitumor activity of the taxol-activated macrophages. Although taxol inhibited the growth of MBT-2 cells, it did not kill the tumor cells. However, preincubation of macrophages with taxol significantly decreased the viability of MBT-2 cells. Secretion of NO correlated with MBT-2 cell killing, and the activated macrophages failed to kill tumor cell targets in the presence of NG-monomethyl-L-arginine, a competitive inhibitor of NO synthase. By the co-culture of macrophages and MBT-2 cells, untreated macrophages also released modest amount of NO and this was synergistically augmented by the treatment with taxol, indicating that MBT-2 tumor cells released some unknown factor that activated the macrophages and enhanced NO production. We named this factor the tumor-derived macrophage activating factor (TMAF). The TMAF-mediated activation of macrophages to enhance the NO production was not blocked by treatment of macrophages with oxidized low-density lipoprotein (Ox-LDL), implying that the scavenger receptor of macrophages is not involved. Sodium nitroprusside (SNP), an NO donor given to the MBT-2 cells, increased the activities of c-Jun N-terminal kinase and caspase-3 in MBT-2 cells and associated with nucleosomal fragmentation or apoptosis, whereas taxol had no direct effect on these parameters. Collectively, our results strongly suggest that taxol kills

  18. Translocator protein (18 kDa) mediates the pro-growth effects of diazepam on Ehrlich tumor cells in vivo.

    Science.gov (United States)

    Sakai, M; Ferraz-de-Paula, V; Pinheiro, M L; Ribeiro, A; Quinteiro-Filho, W M; Rone, M B; Martinez-Arguelles, D B; Dagli, M L Z; Papadopoulos, V; Palermo-Neto, J

    2010-01-25

    The Translocator Protein (TSPO), previously known as the peripheral-type benzodiazepine receptor, is a ubiquitous drug- and cholesterol-binding protein that is up regulated in several types of cancer cells. TSPO drug ligands (e.g., diazepam) induce or inhibit tumor cell proliferation, depending on the dose and tissue origin. We have previously shown that TSPO is expressed in Ehrlich tumor cells and that diazepam increases proliferation of these cells in vitro. Here, we investigated the in vivo effects of diazepam on Ehrlich tumor growth and the role of TSPO in mediating this process. Oral administration of diazepam to mice (3.0mg/kg/day for 7 days) produced plasma and ascitic fluid drug concentrations of 83.83 and 54.12 nM, respectively. Diazepam increased Ehrlich tumor growth, likely due to its ability to increase tumor cell proliferation and Reactive Oxygen Species production. Radioligand binding assays and nucleotide sequencing revealed that Ehrlich tumor cell TSPO had the same pharmacological and biochemical properties as TSPO described in other tumor cells. The estimated K(d) for PK 11195 in Ehrlich tumor cells was 0.44 nM and 8.70 nM (low and high binding site, respectively). Structurally diverse TSPO drug ligands with exclusive affinity for TSPO (i.e., 4-chlordiazepam, Ro5-4864, and isoquinoline-carboxamide PK 11195) also increased Ehrlich tumor growth. However, clonazepam, a GABA(A)-specific ligand with no affinity for TSPO, failed to do so. Taken together, these data suggest that diazepam induces in vivo Ehrlich tumor growth in a TSPO-dependent manner.

  19. Protease-mediated release of chemotherapeutics from mesoporous silica nanoparticles to ex vivo human and mouse lung tumors.

    Science.gov (United States)

    van Rijt, Sabine H; Bölükbas, Deniz A; Argyo, Christian; Datz, Stefan; Lindner, Michael; Eickelberg, Oliver; Königshoff, Melanie; Bein, Thomas; Meiners, Silke

    2015-03-24

    Nanoparticles allow for controlled and targeted drug delivery to diseased tissues and therefore bypass systemic side effects. Spatiotemporal control of drug release can be achieved by nanocarriers that respond to elevated levels of disease-specific enzymes. For example, matrix metalloproteinase 9 (MMP9) is overexpressed in tumors, is known to enhance the metastatic potency of malignant cells, and has been associated with poor prognosis of lung cancer. Here, we report the synthesis of mesoporous silica nanoparticles (MSNs) tightly capped by avidin molecules via MMP9 sequence-specific linkers to allow for site-selective drug delivery in high-expressing MMP9 tumor areas. We provide proof-of-concept evidence for successful MMP9-triggered drug release from MSNs in human tumor cells and in mouse and human lung tumors using the novel technology of ex vivo 3D lung tissue cultures. This technique allows for translational testing of drug delivery strategies in diseased mouse and human tissue. Using this method we show MMP9-mediated release of cisplatin, which induced apoptotic cell death only in lung tumor regions of Kras mutant mice, without causing toxicity in tumor-free areas or in healthy mice. The MMP9-responsive nanoparticles also allowed for effective combinatorial drug delivery of cisplatin and proteasome inhibitor bortezomib, which had a synergistic effect on the (therapeutic) efficiency. Importantly, we demonstrate the feasibility of MMP9-controlled drug release in human lung tumors.

  20. Nanoparticle Delivery of Artesunate Enhances the Anti-tumor Efficiency by Activating Mitochondria-Mediated Cell Apoptosis

    Science.gov (United States)

    Liu, Rui; Yu, Xiwei; Su, Chang; Shi, Yijie; Zhao, Liang

    2017-06-01

    Artemisinin and its derivatives were considered to exert a broad spectrum of anti-cancer activities, and they induced significant anti-cancer effects in tumor cells. Artemisinin and its derivatives could be absorbed quickly, and they were widely distributed, selectively killing tumor cells. Since low concentrations of artesunate primarily depended on oncosis to induce cell death in tumor cells, its anti-tumor effects were undesirable and limited. To obtain better anti-tumor effects, in this study, we took advantage of a new nanotechnology to design novel artesunate-loaded bovine serum albumin nanoparticles to achieve the mitochondrial accumulation of artesunate and induce mitochondrial-mediated apoptosis. The results showed that when compared with free artesunate's reliance on oncotic death, artesunate-loaded bovine serum albumin nanoparticles showed higher cytotoxicity and their significant apoptotic effects were induced through the distribution of artesunate in the mitochondria. This finding indicated that artesunate-loaded bovine serum albumin nanoparticles damaged the mitochondrial integrity and activated mitochondrial-mediated cell apoptosis by upregulating apoptosis-related proteins and facilitating the rapid release of cytochrome C.

  1. Viral-mediated oncolysis is the most critical factor in the late-phase of the tumor regression process upon vaccinia virus infection

    Directory of Open Access Journals (Sweden)

    Yu Yong A

    2011-02-01

    Full Text Available Abstract Background In principle, the elimination of malignancies by oncolytic virotherapy could proceed by different mechanisms - e.g. tumor cell specific oncolysis, destruction of the tumor vasculature or an anti-tumoral immunological response. In this study, we analyzed the contribution of these factors to elucidate the responsible mechanism for regression of human breast tumor xenografts upon colonization with an attenuated vaccinia virus (VACV. Methods Breast tumor xenografts were analyzed 6 weeks post VACV infection (p.i.; regression phase by immunohistochemistry and mouse-specific expression arrays. Viral-mediated oncolysis was determined by tumor growth analysis combined with microscopic studies of intratumoral virus distribution. The tumor vasculature was morphologically characterized by diameter and density measurements and vessel functionality was analyzed by lectin perfusion and extravasation studies. Immunological aspects of viral-mediated tumor regression were studied in either immune-deficient mouse strains (T-, B-, NK-cell-deficient or upon cyclophosphamide-induced immunosuppression (MHCII+-cell depletion in nude mice. Results Late stage VACV-infected breast tumors showed extensive necrosis, which was highly specific to cancer cells. The tumor vasculature in infected tumor areas remained functional and the endothelial cells were not infected. However, viral colonization triggers hyperpermeability and dilatation of the tumor vessels, which resembled the activated endothelium in wounded tissue. Moreover, we demonstrated an increased expression of genes involved in leukocyte-endothelial cell interaction in VACV-infected tumors, which orchestrate perivascular inflammatory cell infiltration. The immunohistochemical analysis of infected tumors displayed intense infiltration of MHCII-positive cells and colocalization of tumor vessels with MHCII+/CD31+ vascular leukocytes. However, GI-101A tumor growth analysis upon VACV-infection in

  2. Anti-tumor Immune Response Mediated by Newcastle Disease Virus HN Gene

    Institute of Scientific and Technical Information of China (English)

    PENG Li-ping; JIN Ning-yi; LI Xiao; SUN Li-li; WEN Zhong-mei; LIU Yan; GAO Peng; HUANG Hai-yan; PIAO Bing-guo; JIN Jing

    2011-01-01

    Hemagglutinin-neuramidinase(HN) is one of the most important surface structure proteins of the Newcastle disease virus(NDV). HN not only mediates receptor recognition but also possesses neuraminidase(NA) activity,which gives it the ability to cleave a component of those receptors, NAcneu. Previous studies have demonstrated that HN has interesting anti-neoplastic and immune-stimulating properties in mammalian species, including humans. To explore the application of the HN gene in cancer gene therapy, we constructed a Lewis lung carcinoma(LLC) solid tumor model using C57BL/6 mice. Mice were injected intratumorally with the recombinant adenovirus expressing HN gene(Ad-HN), and the effect of HN was explored by natural killer cell activity assay, cytotoxic lymphocyte activity assay, T cell subtype evaluation, and Thl/Th2 cytokines analysis. The results demonstrate that HN not only can elicit clonal expansion of both CD4+ and CD8+ T cell populations and cytotoxic T lymphocyte(CTL) and killer cell response, but also skews the immune response toward Thl. Thus, vaccination with Ad-HN may be a potential strategy for cancer gene therapy.

  3. Role of Eosinophils and Tumor Necrosis Factor Alpha in Interleukin-25-Mediated Protection from Amebic Colitis.

    Science.gov (United States)

    Noor, Zannatun; Watanabe, Koji; Abhyankar, Mayuresh M; Burgess, Stacey L; Buonomo, Erica L; Cowardin, Carrie A; Petri, William A

    2017-02-28

    The parasite Entamoeba histolytica is a cause of diarrhea in infants in low-income countries. Previously, it was shown that tumor necrosis factor alpha (TNF-α) production was associated with increased risk of E. histolytica diarrhea in children. Interleukin-25 (IL-25) is a cytokine that is produced by intestinal epithelial cells that has a role in maintenance of gut barrier function and inhibition of TNF-α production. IL-25 expression was decreased in humans and in the mouse model of amebic colitis. Repletion of IL-25 blocked E. histolytica infection and barrier disruption in mice, increased gut eosinophils, and suppressed colonic TNF-α. Depletion of eosinophils with anti-Siglec-F antibody prevented IL-25-mediated protection. In contrast, depletion of TNF-α resulted in resistance to amebic infection. We concluded that IL-25 provides protection from amebiasis, which is dependent upon intestinal eosinophils and suppression of TNF-α.IMPORTANCE The intestinal epithelial barrier is important for protection from intestinal amebiasis. We discovered that the intestinal epithelial cytokine IL-25 was suppressed during amebic colitis in humans and that protection could be restored in the mouse model by IL-25 administration. IL-25 acted via eosinophils and suppressed TNF-α. This work illustrates a previously unrecognized pathway of innate mucosal immune response. Copyright © 2017 Noor et al.

  4. Up-regulation of clusterin during phthalocyanine 4 photodynamic therapy-mediated apoptosis of tumor cells and ablation of mouse skin tumors.

    Science.gov (United States)

    Kalka, K; Ahmad, N; Criswell, T; Boothman, D; Mukhtar, H

    2000-11-01

    Photodynamic therapy (PDT) using the silicon phthalocyanine photo-sensitizer Pc 4 is an oxidative stress associated with the induction of apoptosis in many cancer cells in vitro and in vivo. The mechanisms of PDT-induced tumor cell killing leading to apoptosis are incompletely understood. Clusterin, a widely expressed glycoprotein, is induced in tissues regressing as a consequence of oxidative stress-mediated cell death. Treatment of apoptosis-sensitive human epidermoid carcinoma cells (A431) with PDT resulted in significant up-regulation of clusterin with a maximum at 12 h after treatment, whereas clusterin levels in Pc 4-PDT-treated, apoptosis-resistant, radiation-induced fibrosarcoma (RIF-1) cells remained unchanged. The i.v. administration of Pc 4 to mice bearing chemically or UVB radiation-induced skin papillomas, followed by light application, led to increased clusterin protein expression, peaking 24 h after the treatment, when tumor regression was apparently visible. These data, for the first time, demonstrate the involvement of clusterin in PDT-mediated cell death and during tumor regression. This may have relevance in improving the efficacy of PDT using pharmacological inducers of clusterin.

  5. Expression of tumor necrosis factor-alpha-mediated genes predicts recurrence-free survival in lung cancer.

    Science.gov (United States)

    Wang, Baohua; Song, Ning; Yu, Tong; Zhou, Lianya; Zhang, Helin; Duan, Lin; He, Wenshu; Zhu, Yihua; Bai, Yunfei; Zhu, Miao

    2014-01-01

    In this study, we conducted a meta-analysis on high-throughput gene expression data to identify TNF-α-mediated genes implicated in lung cancer. We first investigated the gene expression profiles of two independent TNF-α/TNFR KO murine models. The EGF receptor signaling pathway was the top pathway associated with genes mediated by TNF-α. After matching the TNF-α-mediated mouse genes to their human orthologs, we compared the expression patterns of the TNF-α-mediated genes in normal and tumor lung tissues obtained from humans. Based on the TNF-α-mediated genes that were dysregulated in lung tumors, we developed a prognostic gene signature that effectively predicted recurrence-free survival in lung cancer in two validation cohorts. Resampling tests suggested that the prognostic power of the gene signature was not by chance, and multivariate analysis suggested that this gene signature was independent of the traditional clinical factors and enhanced the identification of lung cancer patients at greater risk for recurrence.

  6. Expression of tumor necrosis factor-alpha-mediated genes predicts recurrence-free survival in lung cancer.

    Directory of Open Access Journals (Sweden)

    Baohua Wang

    Full Text Available In this study, we conducted a meta-analysis on high-throughput gene expression data to identify TNF-α-mediated genes implicated in lung cancer. We first investigated the gene expression profiles of two independent TNF-α/TNFR KO murine models. The EGF receptor signaling pathway was the top pathway associated with genes mediated by TNF-α. After matching the TNF-α-mediated mouse genes to their human orthologs, we compared the expression patterns of the TNF-α-mediated genes in normal and tumor lung tissues obtained from humans. Based on the TNF-α-mediated genes that were dysregulated in lung tumors, we developed a prognostic gene signature that effectively predicted recurrence-free survival in lung cancer in two validation cohorts. Resampling tests suggested that the prognostic power of the gene signature was not by chance, and multivariate analysis suggested that this gene signature was independent of the traditional clinical factors and enhanced the identification of lung cancer patients at greater risk for recurrence.

  7. Adenosine A2A Receptors Mediate Anti-Inflammatory Effects of Electroacupuncture on Synovitis in Mice with Collagen-Induced Arthritis

    Directory of Open Access Journals (Sweden)

    Qi-hui Li

    2015-01-01

    Full Text Available To study the role of adenosine A2A receptor (A2AR in mediating the anti-inflammatory effect of electroacupuncture (EA on synovitis in collagen-induced arthritis (CIA, C57BL/6 mice were divided into five treatment groups: Sham-control, CIA-control, CIA-EA, CIA-SCH58261 (A2AR antagonist, and CIA-EA-SCH58261. All mice except those in the Sham-control group were immunized with collagen II for arthritis induction. EA treatment was administered using the stomach 36 and spleen 6 points, and stimulated with a continuous rectangular wave for 30 min daily. EA treatment and SCH58261 were administered daily from days 35 to 49 (n=10. After treatment, X-ray radiography of joint bone morphology was established at day 60 and mouse blood was collected for ELISA determination of tumor necrosis factor alpha (TNF-α levels. Mice were sacrificed and processed for histological examination of pathological changes of joint tissue, including hematoxylin-eosin staining and immunohistochemistry of A2AR expression. EA treatment resulted in significantly reduced pathological scores, TNF-α concentrations, and bone damage X-ray scores. Importantly, the anti-inflammatory and tissue-protective effect of EA treatment was reversed by coadministration of SCH58261. Thus, EA treatment exerts an anti-inflammatory effect resulting in significant protection of cartilage by activation of A2AR in the synovial tissue of CIA.

  8. Angiogenesis-independent tumor growth mediated by stem-like cancer cells.

    NARCIS (Netherlands)

    Sakariassen, P.; Prestegarden, L.; Wang, J.; Skaftnesmo, K.O.; Mahesparan, R.; Molthoff, C.F.M.; Sminia, P.; Sundlisaeter, E.; Misra, A.; Tysnes, B.B.; Chekenya, M.; Peters, H.; Lende, G.; Kalland, K.H.; Oyan, A.M.; Petersen, K.; Jonassen, I.; Kogel, A.J. van der; Feuerstein, B.G.; Terzis, A.J.; Bjerkvig, R.; Enger, P.O.

    2006-01-01

    In this work, highly infiltrative brain tumors with a stem-like phenotype were established by xenotransplantation of human brain tumors in immunodeficient nude rats. These tumors coopted the host vasculature and presented as an aggressive disease without signs of angiogenesis. The malignant cells ex

  9. Cancer-induced alterations of NK-mediated target recognition: current and investigational pharmacological strategies aiming at restoring NK-mediated anti-tumor activity

    Directory of Open Access Journals (Sweden)

    Anne-Sophie eChretien

    2014-03-01

    Full Text Available Despite evidence of cancer immune-surveillance, which plays a key role in tumor rejection, cancer cells can escape immune recognition through different mechanisms. Thus, evasion to NK cell mediated anti-tumor activity is commonly described and is mediated by various mechanisms, mainly cancer cell-induced down regulation of NK activating receptors (NCRs, NKG2D, DNAM-1 and CD16 as well as up regulation of inhibitory receptors (KIRs, NKG2A. Alterations of NK cells lead to an impaired recognition of tumor cells as well as a decreased ability to interact with immune cells. Alternatively, cancer cells down-regulate expression of ligands for NK cell activating receptors and up-regulate expression of the ligands for inhibitory receptors. A better knowledge of the extent and the mechanisms of these defects will allow developing pharmacological strategies to restore NK cell ability to recognize and lyse tumor cells. Combining conventional chemotherapy and immune modulation is a promising approach likely to improve clinical outcome in diverse neoplastic malignancies. Here, we overview experimental approaches as well as strategies already available in the clinics that restore NK cell functionality. Yet successful cancer therapies based on the manipulation of NK cell already have shown efficacy in the context of hematologic malignancies. Additionally, the ability of cytotoxic agents to increase susceptibility of tumors to NK cell lysis has been studied and may require improvement to maximize this effect. More recently, new strategies were developed to specifically restore NK cell phenotype or to stimulate NK cell functions. Overall, pharmacological immune modulation trends to be integrated in therapeutic strategies and should improve antitumor effects of conventional cancer therapy.

  10. Human CAR T cells with cell-intrinsic PD-1 checkpoint blockade resist tumor-mediated inhibition.

    Science.gov (United States)

    Cherkassky, Leonid; Morello, Aurore; Villena-Vargas, Jonathan; Feng, Yang; Dimitrov, Dimiter S; Jones, David R; Sadelain, Michel; Adusumilli, Prasad S

    2016-08-01

    Following immune attack, solid tumors upregulate coinhibitory ligands that bind to inhibitory receptors on T cells. This adaptive resistance compromises the efficacy of chimeric antigen receptor (CAR) T cell therapies, which redirect T cells to solid tumors. Here, we investigated whether programmed death-1-mediated (PD-1-mediated) T cell exhaustion affects mesothelin-targeted CAR T cells and explored cell-intrinsic strategies to overcome inhibition of CAR T cells. Using an orthotopic mouse model of pleural mesothelioma, we determined that relatively high doses of both CD28- and 4-1BB-based second-generation CAR T cells achieved tumor eradication. CAR-mediated CD28 and 4-1BB costimulation resulted in similar levels of T cell persistence in animals treated with low T cell doses; however, PD-1 upregulation within the tumor microenvironment inhibited T cell function. At lower doses, 4-1BB CAR T cells retained their cytotoxic and cytokine secretion functions longer than CD28 CAR T cells. The prolonged function of 4-1BB CAR T cells correlated with improved survival. PD-1/PD-1 ligand [PD-L1] pathway interference, through PD-1 antibody checkpoint blockade, cell-intrinsic PD-1 shRNA blockade, or a PD-1 dominant negative receptor, restored the effector function of CD28 CAR T cells. These findings provide mechanistic insights into human CAR T cell exhaustion in solid tumors and suggest that PD-1/PD-L1 blockade may be an effective strategy for improving the potency of CAR T cell therapies.

  11. Tumor-Promoting Circuits That Regulate a Cancer-Related Chemokine Cluster: Dominance of Inflammatory Mediators Over Oncogenic Alterations

    Energy Technology Data Exchange (ETDEWEB)

    Leibovich-Rivkin, Tal [Department of Cell Research and Immunology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978 (Israel); Buganim, Yosef; Solomon, Hilla [Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot 76100 (Israel); Meshel, Tsipi [Department of Cell Research and Immunology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978 (Israel); Rotter, Varda [Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot 76100 (Israel); Ben-Baruch, Adit, E-mail: aditbb@tauex.tau.ac.il [Department of Cell Research and Immunology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978 (Israel)

    2012-01-20

    Here, we investigated the relative contribution of genetic/signaling components versus microenvironmental factors to the malignancy phenotype. In this system, we took advantage of non-transformed fibroblasts that carried defined oncogenic modifications in Ras and/or p53. These cells were exposed to microenvironmental pressures, and the expression of a cancer-related chemokine cluster was used as readout for the malignancy potential (CCL2, CCL5, CXCL8, CXCL10). In cells kept in-culture, synergism between Ras hyper-activation and p53 dysfunction was required to up-regulate the expression of the chemokine cluster. The in vivo passage of Ras{sup High}/p53{sup Low}-modified cells has led to tumor formation, accompanied by potentiation of chemokine release, implicating a powerful role for the tumor microenvironment in up-regulating the chemokine cluster. Indeed, we found that inflammatory mediators which are prevalent in tumor sites, such as TNFα and IL-1β, had a predominant impact on the release of the chemokines, which was substantially higher than that obtained by the oncogenic modifications alone, possibly acting through the transcription factors AP-1 and NF-κB. Together, our results propose that in the unbiased model system that we were using, inflammatory mediators of the tumor milieu have dominating roles over oncogenic modifications in dictating the expression of a pro-malignancy chemokine readout.

  12. Prevention of KLF4-mediated tumor initiation and malignant transformation by UAB30 rexinoid

    Science.gov (United States)

    Jiang, Wen; Deng, Wentao; Bailey, Sarah K.; Nail, Clint D.; Frost, Andra R.; Brouillette, Wayne J.; Muccio, Donald D.; Grubbs, Clinton J.; Ruppert, J. Michael; Lobo-Ruppert, Susan M.

    2009-01-01

    The transcription factor KLF4 acts in post-mitotic epithelial cells to promote differentiation, and functions in a context-dependent fashion as an oncogene. In the skin KLF4 is co-expressed with the nuclear receptors RARγ and RXRα, and formation of the skin permeability barrier is a shared function of these three proteins. We utilized a KLF4-transgenic mouse model of skin cancer in combination with cultured epithelial cells to examine functional interactions between KLF4 and retinoic acid receptors. In cultured cells, activation of a conditional, KLF4-estrogen receptor fusion protein by 4-hydroxytamoxifen resulted in rapid upregulation of transcripts for nuclear receptors including RARγ and RXRα. We tested retinoids in epithelial cell transformation assays, including an RAR-selective agonist (all-trans RA), an RXR-selective agonist (9-cis UAB30, rexinoid), and a pan agonist (9-cis RA). Unlike for several other genes, transformation by KLF4 was inhibited by each retinoid, implicating distinct nuclear receptor heterodimers as modulators of KLF4 transforming activity. When RXRα expression was suppressed by RNAi in cultured cells, transformation was promoted and the inhibitory effect of 9-cis UAB30 was attenuated. Similarly as shown for other mouse models of skin cancer, rexinoid prevented skin tumor initiation resulting from induction of KLF4 in basal keratinocytes. Rexinoid permitted KLF4 expression and KLF4-induced cell cycling, but attenuated the KLF4-induced misexpression of cytokeratin 1 in basal cells. Neoplastic lesions including hyperplasia, dysplasia and squamous cell carcinoma-like lesions were prevented for up to 30 days. Taken together, the results identify retinoid receptors including RXRα as ligand-dependent inhibitors of KLF4-mediated transformation or tumorigenesis. PMID:19197145

  13. Pre-synaptic adenosine A2A receptors control cannabinoid CB1 receptor-mediated inhibition of striatal glutamatergic neurotransmission.

    Science.gov (United States)

    Martire, Alberto; Tebano, Maria Teresa; Chiodi, Valentina; Ferreira, Samira G; Cunha, Rodrigo A; Köfalvi, Attila; Popoli, Patrizia

    2011-01-01

    An interaction between adenosine A(2A) receptors (A(2A) Rs) and cannabinoid CB(1) receptors (CB(1) Rs) has been consistently reported to occur in the striatum, although the precise mechanisms are not completely understood. As both receptors control striatal glutamatergic transmission, we now probed the putative interaction between pre-synaptic CB(1) R and A(2A) R in the striatum. In extracellular field potentials recordings in corticostriatal slices from Wistar rats, A(2A) R activation by CGS21680 inhibited CB(1) R-mediated effects (depression of synaptic response and increase in paired-pulse facilitation). Moreover, in superfused rat striatal nerve terminals, A(2A) R activation prevented, while A(2A) R inhibition facilitated, the CB(1) R-mediated inhibition of 4-aminopyridine-evoked glutamate release. In summary, the present study provides converging neurochemical and electrophysiological support for the occurrence of a tight control of CB(1) R function by A(2A) Rs in glutamatergic terminals of the striatum. In view of the key role of glutamate to trigger the recruitment of striatal circuits, this pre-synaptic interaction between CB(1) R and A(2A) R may be of relevance for the pathogenesis and the treatment of neuropsychiatric disorders affecting the basal ganglia.

  14. In Situ Malignant Transformation and Progenitor-Mediated Cell Budding: Two Different Pathways for Breast Ductal and Lobular Tumor Invasion

    Directory of Open Access Journals (Sweden)

    Yan-gao Man, Mina Izadjoo, Guohong Song, Alexander Stojadinovic

    2011-01-01

    Full Text Available The human breast lobular and ductal structures and the derived tumors from these structures differ substantial in their morphology, microenvironment, biological presentation, functions, and clinical prognosis. Based on these differences, we have proposed that pre-invasive lobular tumors may progress to invasive lesions through “in situ malignant transformation”, in which the entire myoepithelial cell layer within a given lobule or lobular clusters undergoes extensive degeneration and disruptions, which allows the entire epithelial cell population associated with these myoepithelial cell layers directly invade the stroma or vascular structures. In contrast, pre-invasive ductal tumors may invade the stroma or vascular structures through “progenitor-mediated cell budding”, in which focal myoepithelial cell degeneration-induced aberrant leukocyte infiltration causes focal disruptions in the tumor capsules, which selectively favor monoclonal proliferation of the overlying tumor stem cells or a biologically more aggressive cell clone. Our current study attempted to provide more direct morphological and immunohistochemical data that are consistent with our hypotheses.

  15. RAGE mediates S100A7-induced breast cancer growth and metastasis by modulating the tumor microenvironment

    Science.gov (United States)

    Nasser, Mohd W.; Wani, Nissar Ahmad; Ahirwar, Dinesh K.; Powell, Catherine A.; Ravi, Janani; Elbaz, Mohamad; Zhao, Helong; Padilla, Laura; Zhang, Xiaoli; Shilo, Konstantin; Ostrowski, Michael; Shapiro, Charles; Carson, William E.; Ganju, Ramesh K.

    2015-01-01

    RAGE is a multi-functional receptor implicated in diverse processes including inflammation and cancer. In this study, we report that RAGE expression is upregulated widely in aggressive triple-negative breast cancer cells, both in primary tumors and lymph node metastases. In evaluating the functional contributions of RAGE in breast cancer, we found RAGE-deficient mice displayed a reduced propensity for breast tumor growth. In an established model of lung metastasis, systemic blockade by injection of a RAGE neutralizing antibody inhibited metastasis development. Mechanistic investigations revealed that RAGE bound to the pro-inflammatory ligand S100A7 and mediated its ability to activate ERK, NF-κB and cell migration. In an S100A7 transgenic mouse model of breast cancer (mS100a7a15 mice), administration of either RAGE neutralizing antibody or soluble RAGE was sufficient to inhibit tumor progression and metastasis. In this model, we found that RAGE/S100A7 conditioned the tumor microenvironment by driving the recruitment of MMP9-positive tumor-associated macrophages. Overall, our results highlight RAGE as a candidate biomarker for triple-negative breast cancers and they reveal a functional role for RAGE/S100A7 signaling in linking inflammation to aggressive breast cancer development. PMID:25572331

  16. Transient mild hyperthermia induces E-selectin mediated localization of mesoporous silicon vectors in solid tumors.

    Directory of Open Access Journals (Sweden)

    Dickson K Kirui

    Full Text Available BACKGROUND: Hyperthermia treatment has been explored as a strategy to overcome biological barriers that hinder effective drug delivery in solid tumors. Most studies have used mild hyperthermia treatment (MHT to target the delivery of thermo-sensitive liposomes carriers. Others have studied its application to permeabilize tumor vessels and improve tumor interstitial transport. However, the role of MHT in altering tumor vessel interfacial and adhesion properties and its relationship to improved delivery has not been established. In the present study, we evaluated effects of MHT treatment on tumor vessel flow dynamics and expression of adhesion molecules and assessed enhancement in particle localization using mesoporous silicon vectors (MSVs. We also determined the optimal time window at which maximal accumulation occur. RESULTS: In this study, using intravital microscopy analyses, we showed that temporal mild hyperthermia (∼1 W/cm(2 amplified delivery and accumulation of MSVs in orthotopic breast cancer tumors. The number of discoidal MSVs (1000×400 nm adhering to tumor vasculature increased 6-fold for SUM159 tumors and 3-fold for MCF-7 breast cancer tumors. By flow chamber experiments and Western blotting, we established that a temporal increase in E-selectin expression correlated with enhanced particle accumulation. Furthermore, MHT treatment was shown to increase tumor perfusion in a time-dependent fashion. CONCLUSIONS: Our findings reveal that well-timed mild hyperthermia treatment can transiently elevate tumor transport and alter vascular adhesion properties and thereby provides a means to enhance tumor localization of non-thermally sensitive particles such as MSVs. Such enhancement in accumulation could be leveraged to increase therapeutic efficacy and reduce drug dosing in cancer therapy.

  17. Inhibition of PlexA1-mediated brain tumor growth and tumor-associated angiogenesis using a transmembrane domain targeting peptide

    Science.gov (United States)

    Jacob, Laurent; Goetz, Jacky; Vermot, Julien; Fernandez, Aurore; Baumlin, Nadège; Aci-Sèche, Samia; Orend, Gertraud; Roussel, Guy; Crémel, Gérard; Genest, Monique; Hubert, Pierre; Bagnard, Dominique

    2016-01-01

    The neuropilin-plexin receptor complex regulates tumor cell migration and proliferation and thus is an interesting therapeutic target. High expression of neuropilin-1 is indeed associated with a bad prognosis in glioma patients. Q-RTPCR and tissue-array analyses showed here that Plexin-A1 is highly expressed in glioblastoma and that the highest level of expression correlates with the worse survival of patients. We next identified a developmental and tumor-associated pro-angiogenic role of Plexin-A1. Hence, by using molecular simulations and a two-hybrid like assay in parallel with biochemical and cellular assays we developed a specific Plexin-A1 peptidic antagonist disrupting transmembrane domain-mediated oligomerization of the receptor and subsequent signaling and functional activity. We found that this peptide exhibits anti-tumor activity in vivo on different human glioblastoma models including glioma cancer stem cells. Thus, screening Plexin-A1 expression and targeting Plexin-A1 in glioblastoma patients exhibit diagnostic and therapeutic value. PMID:27506939

  18. Secretory phospholipase A2-mediated neuronal cell death involves glutamate ionotropic receptors

    DEFF Research Database (Denmark)

    de Turco, Elena B; Diemer, Nils Henrik; Bazan, Nicolas G

    2002-01-01

    To define the significance of glutamate ionotropic receptors in sPLA -mediated neuronal cell death we used the NMDA receptor antagonist MK-801 and the AMPA receptor antagonist PNQX. In primary neuronal cell cultures both MK-801 and PNQX inhibited sPLA - and glutamate-induced neuronal death. [ H]A...

  19. A lupus anti-DNA autoantibody mediates autocatalytic, targeted delivery of nanoparticles to tumors

    Science.gov (United States)

    Chen, Zeming; Patel, Jaymin M.; Noble, Philip W.; Garcia, Cesar; Hong, Zhangyong; Hansen, James E.; Zhou, Jiangbing

    2016-01-01

    Strategies to target nanoparticles to tumors that rely on surface modification with ligands that bind molecules overexpressed on cancer cells or the tumor neovasculature suffer from a major limitation: with delivery of toxic agents the amount of molecules available for targeting decreases with time; consequently, the efficiency of nanoparticle delivery is reduced. To overcome this limitation, here we propose an autocatalytic tumor-targeting mechanism based on targeting extracellular DNA (exDNA). exDNA is enriched in the tumor microenviroment and increases with treatment with cytotoxic agents, such as doxorubicin (DOX), due to release of DNA by dying tumor cells. We tested this approach using poly(lactic-co-glycolic acid) (PLGA) nanoparticles surface-conjugated with fragments of 3E10 (3E10EN), a lupus anti-DNA autoantibody. We demonstrated that 3E10EN-conjugated nanoparticles bound to DNA and preferentially localized to tumors in vivo. The efficiency of tumor localization of 3E10EN-conjugated, DOX-loaded nanoparticles increased with time and subsequent treatments, demonstrating an autocatalytic effect. 3E10EN-conjugated DOX-loaded nanoparticles exhibited a significant anti-tumor effect that was superior to all controls. This work demonstrates the promise of autocatalytic drug delivery mechanisms and establishes proof of concept for a new anti-DNA autoantibody-based approach for enhancing delivery of nanoparticles to tumors. PMID:27494868

  20. Immunostimulation-Mediated Anti-Tumor Activity of Bamboo (Sasa senanensis Leaf Extracts Obtained under ‘Vigorous’ Condition

    Directory of Open Access Journals (Sweden)

    Takahiro Seki

    2010-01-01

    Full Text Available Traditional Japanese medicine uses the leaves of Kumaizasa bamboo extracted in hot water at 100°C. For this study, we developed a new, ‘vigorous’ extraction method involving steps at 100, 121 and 196°C. This procedure not only yielded greater amounts of extract but also with significant increase in immunostimulating activity, which induces activation of human natural killer (NK cells, macrophages and potent induction of IL-2, IL-12 and IFN-γ in tumor bearing mice. The efficacy of the extract to facilitate phagocytosis and nitric oxide production by mouse peritoneal macrophages was determined and compared with that of 1,3-β-glucan. Anti-tumor activity was evaluated in vivo in several mouse tumor models (S-180, C38 and Meth-A. Oral administration of the extracts was carried out when tumor reached size of approximately 6 mm at concentrations of 0.05% or higher. The extracts significantly suppressed tumor growth in S-180 and C38 tumor models. Overall survival was significantly prolonged in the treatment group than that of control. Activation of macrophages and NK cells by the extracts suggests that the anti-tumor efficacy of the extract is mediated by immunopotentiation. The extracts resolved into three major fractions (F-I, F-II and F-III in Sephadex gel chromatography. Fraction F-I consists of 1,3-β-glucan and stimulated both macrophages and NK cells suggesting that it may be the primary immunopotentiating factor in suppressing cancer. Fraction F-III has potent free radical scavenging effects and may play an important role in cancer prevention. These results warrant further translation and clinical investigations.

  1. Shigella mediated depletion of macrophages in a murine breast cancer model is associated with tumor regression.

    Directory of Open Access Journals (Sweden)

    Katharina Galmbacher

    Full Text Available A tumor promoting role of macrophages has been described for a transgenic murine breast cancer model. In this model tumor-associated macrophages (TAMs represent a major component of the leukocytic infiltrate and are associated with tumor progression. Shigella flexneri is a bacterial pathogen known to specificly induce apotosis in macrophages. To evaluate whether Shigella-induced removal of macrophages may be sufficient for achieving tumor regression we have developed an attenuated strain of S. flexneri (M90TDeltaaroA and infected tumor bearing mice. Two mouse models were employed, xenotransplantation of a murine breast cancer cell line and spontanous breast cancer development in MMTV-HER2 transgenic mice. Quantitative analysis of bacterial tumor targeting demonstrated that attenuated, invasive Shigella flexneri primarily infected TAMs after systemic administration. A single i.v. injection of invasive M90TDeltaaroA resulted in caspase-1 dependent apoptosis of TAMs followed by a 74% reduction in tumors of transgenic MMTV-HER-2 mice 7 days post infection. TAM depletion was sustained and associated with complete tumor regression.These data support TAMs as useful targets for antitumor therapy and highlight attenuated bacterial pathogens as potential tools.

  2. Sulindac reversal of 15-PGDH-mediated resistance to colon tumor chemoprevention with NSAIDs.

    Science.gov (United States)

    Fink, Stephen P; Dawson, Dawn M; Zhang, Yongyou; Kresak, Adam; Lawrence, Earl G; Yang, Peiying; Chen, Yanwen; Barnholtz-Sloan, Jill S; Willis, Joseph E; Kopelovich, Levy; Markowitz, Sanford D

    2015-02-01

    Non-steroidal anti-inflammatory drugs prevent colorectal cancer by inhibiting cyclooxygenase (COX) enzymes that synthesize tumor-promoting prostaglandins. 15-hydroxyprostaglandin dehydrogenase (15-PGDH) is a tumor suppressor that degrades tumor-promoting prostaglandins. Murine knockout of 15-PGDH increases susceptibility to azoxymethane-induced colon tumors. It also renders these mice resistant to celecoxib, a selective inhibitor of inducible COX-2 during colon neoplasia. Similarly, humans with low colonic 15-PGDH are also resistant to colon adenoma prevention with celecoxib. Here, we used aspirin and sulindac, which inhibit both COX-1 and COX-2, in order to determine if these broader COX inhibitors can prevent colon tumors in 15-PGDH knockout (KO) mice. Unlike celecoxib, sulindac proved highly effective in colon tumor prevention of 15-PGDH KO mice. Significantly, however, aspirin demonstrated no effect on colon tumor incidence in either 15-PGDH wild-type or KO mice, despite a comparable reduction in colonic mucosal Prostaglandin E₂ (PGE₂) levels by both sulindac and aspirin. Notably, colon tumor prevention activity by sulindac was accompanied by a marked induction of lymphoid aggregates and proximal colonic inflammatory mass lesions, a side effect seen to a lesser degree with celecoxib, but not with aspirin. These findings suggest that sulindac may be the most effective agent for colon cancer prevention in humans with low 15-PGDH, but its use may also be associated with inflammatory lesions in the colon.

  3. Tumor-associated fibroblasts as "Trojan Horse" mediators of resistance to anti-VEGF therapy.

    Science.gov (United States)

    Francia, Giulio; Emmenegger, Urban; Kerbel, Robert S

    2009-01-06

    While targeting VEGF has shown success against a number of human cancers, drug resistance has resulted in compromised clinical benefits. In this issue of Cancer Cell, Crawford et al. (2009) report that tumors resistant to anti-VEGF therapy stimulate tumor-associated fibroblasts to express proangiogenic PDGF-C, implicating it as a potential therapeutic target.

  4. Mechanism-Based Tumor-Targeting Drug Delivery System. Validation of Efficient Vitamin Receptor-Mediated Endocytosis and Drug Release

    Energy Technology Data Exchange (ETDEWEB)

    Chen, S.; Wong, S.; Zhao, X.; Chen, J.; Chen, J.; Kuznetsova, L.; Ojima, I.

    2010-05-01

    An efficient mechanism-based tumor-targeting drug delivery system, based on tumor-specific vitamin-receptor mediated endocytosis, has been developed. The tumor-targeting drug delivery system is a conjugate of a tumor-targeting molecule (biotin: vitamin H or vitamin B-7), a mechanism-based self-immolative linker and a second-generation taxoid (SB-T-1214) as the cytotoxic agent. This conjugate (1) is designed to be (i) specific to the vitamin receptors overexpressed on tumor cell surface and (ii) internalized efficiently through receptor-mediated endocytosis, followed by smooth drug release via glutathione-triggered self-immolation of the linker. In order to monitor and validate the sequence of events hypothesized, i.e., receptor-mediated endocytosis of the conjugate, drug release, and drug-binding to the target protein (microtubules), three fluorescent/fluorogenic molecular probes (2, 3, and 4) were designed and synthesized. The actual occurrence of these processes was unambiguously confirmed by means of confocal fluorescence microscopy (CFM) and flow cytometry using L1210FR leukemia cells, overexpressing biotin receptors. The molecular probe 4, bearing the taxoid linked to fluorescein, was also used to examine the cell specificity (i.e., efficacy of receptor-based cell targeting) for three cell lines, L1210FR (biotin receptors overexpressed), L1210 (biotin receptors not overexpressed), and WI38 (normal human lung fibroblast, biotin receptor negative). As anticipated, the molecular probe 4 exhibited high specificity only to L1210FR. To confirm the direct correlation between the cell-specific drug delivery and anticancer activity of the probe 4, its cytotoxicity against these three cell lines was also examined. The results clearly showed a good correlation between the two methods. In the same manner, excellent cell-specific cytotoxicity of the conjugate 1 (without fluorescein attachment to the taxoid) against the same three cell lines was confirmed. This mechanism

  5. Cox7a2 mediates steroidogenesis in TM3 mouse Leydig cells

    Institute of Scientific and Technical Information of China (English)

    Liang Chen; Zhong-Cheng Xin; Xin Li; Long Tian; Yi-Ming Yuan; Gang Liu; Xue-Jun Jiang; Ying-Lu Guo

    2006-01-01

    Aim: To investigate the regulatory function of Cox7a2 on steroidogenesis and the mechanism involved in TM3 mouse Leydig cells. Methods: The cDNA of Cox7a2 was cloned from TM3 mouse Leydig cells. It was subcloned to pDsRedExpress-N1 and transfected back into TM3 mouse Leydig cells for Cox7a2 overexpression by transient gene transfection.Steroidogenesis affected by overexpressed Cox7a2 was studied by ELISA. To elicit the mechanism of this effect,expression of steroidogenic acute regulatory (StAR) protein and reactive oxygen species (ROS) were examined by Western blot and fluorometer, respectively. Results: The cDNA of Cox7a2 (249 bp) was cloned from Leydig cells and confirmed by DNA sequencing. After constructed pDsRed-Express-Nl-Cox7a2 was transfected back into TM3 mouse Leydig cells, Cox7a2 inhibited not only luteinizing hormone (LH)-induced secretion of testosterone but also the expression of StAR protein. At the same time, Cox7a2 increased the activity of ROS in TM3 mouse Leydig cells. Conclusion:Cox7a2 inhibited LH-induced StAR protein expression, and consequent testosterone production, at least in part, by increasing ROS activity in TM3 mouse Leydig cells.

  6. Near-infrared fluorescence imaging of cancer mediated by tumor hypoxia and HIF1α/OATPs signaling axis.

    Science.gov (United States)

    Wu, Jason Boyang; Shao, Chen; Li, Xiangyan; Shi, Changhong; Li, Qinlong; Hu, Peizhen; Chen, Yi-Ting; Dou, Xiaoliang; Sahu, Divya; Li, Wei; Harada, Hiroshi; Zhang, Yi; Wang, Ruoxiang; Zhau, Haiyen E; Chung, Leland W K

    2014-09-01

    Near-infrared fluorescence (NIRF) imaging agents are promising tools for noninvasive cancer imaging. Here, we explored the mechanistic properties of a specific group of NIR heptamethine carbocyanines including MHI-148 dye we identified and synthesized, and demonstrated these dyes to achieve cancer-specific imaging and targeting via a hypoxia-mediated mechanism. We found that cancer cells and tumor xenografts exhibited hypoxia-dependent MHI-148 dye uptake in vitro and in vivo, which was directly mediated by hypoxia-inducible factor 1α (HIF1α). Microarray analysis and dye uptake assay further revealed a group of hypoxia-inducible organic anion-transporting polypeptides (OATPs) responsible for dye uptake, and the correlation between OATPs and HIF1α was manifested in progressive clinical cancer specimens. Finally, we demonstrated increased uptake of MHI-148 dye in situ in perfused clinical tumor samples with activated HIF1α/OATPs signaling. Our results establish these NIRF dyes as potential tumor hypoxia-dependent cancer-targeting agents and provide a mechanistic rationale for continued development of NIRF imaging agents for improved cancer detection, prognosis and therapy.

  7. Stem cell factor-mediated wild-type KIT receptor activation is critical for gastrointestinal stromal tumor cell growth

    Institute of Scientific and Technical Information of China (English)

    Chen-Guang Bai; Xiao-Wei Hou; Feng Wang; Cen Qiu; Yan Zhu; Ling Huang; Jing Zhao

    2012-01-01

    AIM:To clarify the biological role of stem cell factor (SCF)-mediated wild-type KIT receptor activation in gastrointestinal stromal tumor (GIST) growth.METHODS:The co-expression of wild-type KIT receptor and SCF was evaluated in 51 GIST samples using mutation analysis and immunohistochemistry,and the results were correlated with clinicopathological parameters,including the mitotic count,proliferative index (Ki-67 immunohistochemical staining),mitotic index (phospho-histone H3 immunohistochemical staining)and apoptotic index (terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling).Using primary cultured GIST cells,the effect of SCF-mediated wild-type KIT receptor activation was determined by western blotting,methyl thiazolyl tetrazolium (MTT),and apoptosis assays.RESULTS:We found that wild-type KIT receptor and SCF protein were expressed in 100% and 76.5% of the 51 GIST samples,respectively,and the co-expression of wild-type KIT receptor and SCF was associated with known indicators of poor prognosis,including larger tumor size (P =0.0118),higher mitotic count (P =0.0058),higher proliferative index (P =0.0012),higher mitotic index (P =0.0282),lower apoptosis index (P =0.0484),and increased National Institutes of Health risk level (P =0.0012).We also found that the introduction of exogenous SCF potently increased KIT kinase activity,stimulated cell proliferation (P < 0.01) and inhibited apoptosis (P < 0.01) induced by serum starvation,while a KIT immunoblocking antibody suppressed proliferation (P =0.01) and promoted apoptosis (P < 0.01)in cultured GIST cells.CONCLUSION:SCF-mediated wild-type KIT receptor activation plays an important role in GIST cell growth.The inhibition of SCF-mediated wild-type KIT receptor activation may prove to be particularly important for GIST therapy.

  8. Inhibition of tumor growth in xenografted nude mice with adenovirus-mediated endostatin gene comparison with recombinant endostatin protein

    Institute of Scientific and Technical Information of China (English)

    梁志慧; 吴沛宏; 李立; 薛刚; 曾益新; 黄文林

    2004-01-01

    Background Inhibition of tumor growth by endostatin has been shown to be an effective strategy in cancer therapy in mice. However, its widespread application has been hampered by difficulties in a large-scale production of the recombinant endostatin protein, rapid loss bioactivity of the protein, and the cumbersome daily administration. These limitations could be resolved by in vivo delivery and expression of the endostatin gene. In this study, we observed the effect and advantage of endostatin gene therapy mediated by a recombinant adenoviral vector (Ad/hEndo) on the growth of hepatocellular carcinoma BEL-7402 xenografted tumors, comparison with recombinant endostatin protein.Results After 4 courses of treatment, the tumor growth rates of high-dose treated group with 1×109 pfu of Ad/hEndo were inhibited by 42.26% compared with the Ad/LacZ control group (P=0.001) and by 46.26% compared with the NIH buffer control group (P=0.003), respectively. However, in this study, Ad/hEndo at low dose of 5×108 pfu failed to demonstrate significant inhibition of tumor growth, compared with control groups. After daily administration of recombinant human endostatin protein (rhEndo) for 9 days, the ratio of T/C (rhEndo group versus PBS group) was less than 47%. However, two days after rhEndo treatment ceased, the ratio of T/C was more than 50%. The peak of expression of endostatin mRNA in tumor tissue was at 2 or 3 days after administration intratumorally with Ad/hEndo of 1×109 pfu and gradually dropped undetectable by day 7. Dynamic analysis of endostatin concentration in tumor tissue showed that the highest level of mRNA is up at the third day after injection, and dropped to basal level three weeks later.Conclusions Endostatin gene therapy mediated by a recombinant adenoviral vector had significantly inhibited the growth of hepatocellular carcinoma BEL-7402 xenografted tumors at a high dose of 1×109 pfu compared with other groups. The analysis of dynamic expression of

  9. CD44v6 regulates growth of brain tumor stem cells partially through the AKT-mediated pathway.

    Directory of Open Access Journals (Sweden)

    Mayumi Jijiwa

    Full Text Available Identification of stem cell-like brain tumor cells (brain tumor stem-like cells; BTSC has gained substantial attention by scientists and physicians. However, the mechanism of tumor initiation and proliferation is still poorly understood. CD44 is a cell surface protein linked to tumorigenesis in various cancers. In particular, one of its variant isoforms, CD44v6, is associated with several cancer types. To date its expression and function in BTSC is yet to be identified. Here, we demonstrate the presence and function of the variant form 6 of CD44 (CD44v6 in BTSC of a subset of glioblastoma multiforme (GBM. Patients with CD44(high GBM exhibited significantly poorer prognoses. Among various variant forms, CD44v6 was the only isoform that was detected in BTSC and its knockdown inhibited in vitro growth of BTSC from CD44(high GBM but not from CD44(low GBM. In contrast, this siRNA-mediated growth inhibition was not apparent in the matched GBM sample that does not possess stem-like properties. Stimulation with a CD44v6 ligand, osteopontin (OPN, increased expression of phosphorylated AKT in CD44(high GBM, but not in CD44(low GBM. Lastly, in a mouse spontaneous intracranial tumor model, CD44v6 was abundantly expressed by tumor precursors, in contrast to no detectable CD44v6 expression in normal neural precursors. Furthermore, overexpression of mouse CD44v6 or OPN, but not its dominant negative form, resulted in enhanced growth of the mouse tumor stem-like cells in vitro. Collectively, these data indicate that a subset of GBM expresses high CD44 in BTSC, and its growth may depend on CD44v6/AKT pathway.

  10. Functional balance between T cell chimeric receptor density and tumor associated antigen density: CTL mediated cytolysis and lymphokine production.

    Science.gov (United States)

    Weijtens, M E; Hart, E H; Bolhuis, R L

    2000-01-01

    Genetically engineered expression of tumor-specific single chain antibody chimeric receptors (ch-Rec) on human T lymphocytes endow these cells with the parental monoclonal antibody (mAb) dictated tumor specificity and may be useful for clinical immuno-genetherapy. Therefore it was of importance to assess how the densities of tumor-specific receptors and tumor associated antigens (TAA), respectively, affect primary human T lymphocyte functions in relation to target cell susceptibilities to lysis. We therefore studied the functional balance between ch-Rec densities on human T lymphocytes and TAA on tumor cells. The gene construct encoding a ch-Rec derived from (1) a renal carcinoma cell (RCC) specific mouse mAb (G250), and (2) the human signal transducing Fc(epsilon)RI gamma-chain was used. To obtain ch-RecHIGH-POS and ch-RecLOW-POS T lymphocytes, two distinct retroviral vectors were used to introduce the gene constructs into primary human T lymphocytes. Levels of ch-Rec-redirected T lymphocyte mediated tumor cell lysis, as well as lymphokine production were determined using RCC lines as target/stimulator cells, which express either no or increasing densities of the TAA. A functional and dynamic balance between ch-Rec densities on cytotoxic T lymphocytes (CTLs) on the one hand and TAA densities on RCCs on the other, was found. In short, ch-RecHIGH-POS CTLs are triggered by TAAHIGH-POS as well as TAALOW-POS RCCs to lyse tumor cells and produce (IFN-gamma and TNF-alpha) lymphokine. In contrast, ch-RecLOW-POS T lymphocytes are only triggered for cytolysis and lymphokine production by relatively TAAHIGH-POS RCCs. In conclusion, (1) the activation of T lymphocyte responses is co-determined by the expression levels of the ch-Rec on T lymphocytes and the TAA on tumor cells and (2) at relatively high T lymphocyte ch-Rec expression levels the CTLs lyse tumor cells with a wide range of TAA densities. Gene Therapy (2000) 7, 35-42.

  11. Antibody-mediated phagocytosis contributes to the anti-tumor activity of the therapeutic antibody daratumumab in lymphoma and multiple myeloma

    DEFF Research Database (Denmark)

    Overdijk, M. B.; Verploegen, S.; Bogels, M.

    2015-01-01

    in MM and other hematological tumors, led us to investigate the contribution of antibody-dependent, macrophage-mediated phagocytosis to DARA's mechanism of action. Live cell imaging revealed that DARA efficiently induced macrophage-mediated phagocytosis, in which individual macrophages rapidly...... and sequentially engulfed multiple tumor cells. DARA-dependent phagocytosis by mouse and human macrophages was also observed in an in vitro flow cytometry assay, using a range of MM and Burkitt's lymphoma cell lines. Phagocytosis contributed to DARA's anti-tumor activity in vivo, in both a subcutaneous...

  12. Surface chemistry-mediated penetration and gold nanorod thermotherapy in multicellular tumor spheroids

    Science.gov (United States)

    Jin, Shubin; Ma, Xiaowei; Ma, Huili; Zheng, Kaiyuan; Liu, Juan; Hou, Shuai; Meng, Jie; Wang, Paul C.; Wu, Xiaochun; Liang, Xing-Jie

    2012-12-01

    We investigated the penetration and thermotherapy efficiency of different surface coated gold nanorods (Au NRs) in multicellular tumor spheroids. The current data show that negatively charged Au NRs, other than positively charged Au NRs, can penetrate deep into the tumor spheroids and achieve a significant thermal therapeutic benefit.We investigated the penetration and thermotherapy efficiency of different surface coated gold nanorods (Au NRs) in multicellular tumor spheroids. The current data show that negatively charged Au NRs, other than positively charged Au NRs, can penetrate deep into the tumor spheroids and achieve a significant thermal therapeutic benefit. Electronic supplementary information (ESI) available: Materials and methods section. See DOI: 10.1039/c2nr31877f

  13. Osteoprotegerin mediates tumor-promoting effects of Interleukin-1beta in breast cancer cells

    NARCIS (Netherlands)

    Chung, S.T.M. (Stephanie Tsang Mui); D. Geerts (Dirk); Roseman, K. (Kim); Renaud, A. (Ashleigh); Connelly, L. (Linda)

    2017-01-01

    markdownabstract__Background:__ It is widely recognized that inflammation promotes breast cancer invasion and metastasis. Given the complex nature of the breast tumor inflammatory microenvironment, much remains to be understood of the molecular mechanisms that govern these effects. We have

  14. Selective alpha-particle mediated depletion of tumor vasculature with vascular normalization.

    Directory of Open Access Journals (Sweden)

    Jaspreet Singh Jaggi

    Full Text Available BACKGROUND: Abnormal regulation of angiogenesis in tumors results in the formation of vessels that are necessary for tumor growth, but compromised in structure and function. Abnormal tumor vasculature impairs oxygen and drug delivery and results in radiotherapy and chemotherapy resistance, respectively. Alpha particles are extraordinarily potent, short-ranged radiations with geometry uniquely suitable for selectively killing neovasculature. METHODOLOGY AND PRINCIPAL FINDINGS: Actinium-225 ((225Ac-E4G10, an alpha-emitting antibody construct reactive with the unengaged form of vascular endothelial cadherin, is capable of potent, selective killing of tumor neovascular endothelium and late endothelial progenitors in bone-marrow and blood. No specific normal-tissue uptake of E4G10 was seen by imaging or post-mortem biodistribution studies in mice. In a mouse-model of prostatic carcinoma, (225Ac-E4G10 treatment resulted in inhibition of tumor growth, lower serum prostate specific antigen level and markedly prolonged survival, which was further enhanced by subsequent administration of paclitaxel. Immunohistochemistry revealed lower vessel density and enhanced tumor cell apoptosis in (225Ac-E4G10 treated tumors. Additionally, the residual tumor vasculature appeared normalized as evident by enhanced pericyte coverage following (225Ac-E4G10 therapy. However, no toxicity was observed in vascularized normal organs following (225Ac-E4G10 therapy. CONCLUSIONS: The data suggest that alpha-particle immunotherapy to neovasculature, alone or in combination with sequential chemotherapy, is an effective approach to cancer therapy.

  15. Lewis antigen mediated adhesion of freshly removed human bladder tumors to E-selectin

    DEFF Research Database (Denmark)

    Skorsteensgaard, Karna; Vestergaard, Else Marie; Langkilde, Niels;

    1999-01-01

    in invasive tumors. The binding property was correlated to the detection of carbohydrate structures in Western blots and tissue sections of the same tumors, using six different monoclonal antibodies: anti-sLe(a), anti-sLe(x), anti-Le(a), anti-Le(x) (two different clones) and anti-Le(b). Most blot-stainings.......001), and was correlated to number of bound cells (p staining of Le(a) on cell membranes correlated with frequent binding (p

  16. Specific killing of P53 mutated tumor cell lines by a cross-reactive human HLA-A2-restricted P53-specific CTL line

    DEFF Research Database (Denmark)

    Würtzen, P A; Pedersen, L O; Poulsen, H S

    2001-01-01

    , 4 HLA-A2(+) p53-mutated tumor cell lines were lysed by the CTL line, indicating that these peptides are endogenously processed and presented on HLA-A2 molecule. Thus, monocyte-derived DC pulsed with a pool of peptides are able to induce CTL reactivity to wild-type p53 peptides presented by several...

  17. Bacteria-mediated in vivo delivery of quantum dots into solid tumor

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Ying [Single-molecule and Nanobiology Lab., Dept. of Biophysics, School of Basic Medical Sciences, Peking University, No. 38 Xue Yuan Road, Beijing 100091 (China); Zhou, Mei [Dept. of Radiation Medicine, School of Basic Medical Sciences, Peking University, No. 38 Xue Yuan Road, Beijing 100091 (China); Luo, Dan; Wang, Lijun; Hong, Yuankai [Single-molecule and Nanobiology Lab., Dept. of Biophysics, School of Basic Medical Sciences, Peking University, No. 38 Xue Yuan Road, Beijing 100091 (China); Yang, Yepeng, E-mail: yangyepeng@bjmu.edu.cn [Dept. of Radiation Medicine, School of Basic Medical Sciences, Peking University, No. 38 Xue Yuan Road, Beijing 100091 (China); Sha, Yinlin, E-mail: shyl@hsc.pku.edu.cn [Single-molecule and Nanobiology Lab., Dept. of Biophysics, School of Basic Medical Sciences, Peking University, No. 38 Xue Yuan Road, Beijing 100091 (China); Biomed-X Center, Peking University, Peking University, No. 38 Xue Yuan Road, Beijing 100091 (China)

    2012-09-07

    Highlights: Black-Right-Pointing-Pointer New approach using the probiotic Bifidobacterium bifidum as a vehicle to deliver QDs into the deep tissue of solid tumors in vivo was achieved. Black-Right-Pointing-Pointer Bifidobacterium bifidum delivery system has intrinsic biocompatibility. Black-Right-Pointing-Pointer The targeting efficacy was improved by folic acids. -- Abstract: Semiconductor nanocrystals, so-called quantum dots (QDs), promise potential application in bioimaging and diagnosis in vitro and in vivo owing to their high-quality photoluminescence and excellent photostability as well as size-tunable spectra. Here, we describe a biocompatible, comparatively safe bacteria-based system that can deliver QDs specifically into solid tumor of living animals. In our strategy, anaerobic bacterium Bifidobacterium bifidum (B. bifidum) that colonizes selectively in hypoxic regions of animal body was successfully used as a vehicle to load with QDs and transported into the deep tissue of solid tumors. The internalization of lipid-encapsuled QDs into B. bifidum was conveniently carried by electroporation. To improve the efficacy and specificity of tumor targeting, the QDs-carrying bacterium surface was further conjugated with folic acids (FAs) that can bind to the folic acid receptor overexpressed tumor cells. This new approach opens a pathway for delivering different types of functional cargos such as nanoparticles and drugs into solid tumor of live animals for imaging, diagnosis and therapy.

  18. Membrane estrogen receptor-α-mediated nongenomic actions of phytoestrogens in GH3/B6/F10 pituitary tumor cells

    OpenAIRE

    Jeng, Yow-Jiun; Kochukov, Mikhail Y.; Watson, Cheryl S

    2009-01-01

    Background: Estradiol (E2) mediates various intracellular signaling cascades from the plasma membrane via several estrogen receptors (ERs). The pituitary is an estrogen-responsive tissue, and we have previously reported that E2 can activate mitogen-activated protein kinases (MAPKs) such as ERK1/2 and JNK1/2/3 in the membrane ERα (mERα)-enriched GH3/B6/F10 rat pituitary tumor cell line. Phytoestrogens are compounds found in plants and foods such as soybeans, alfalfa sprouts, and red grapes. Th...

  19. Staphylococcus aureus - induced tumor necrosis factor - related apoptosis - inducing ligand expression mediates apoptosis and caspase-8 activation in infected osteoblasts

    Directory of Open Access Journals (Sweden)

    Bost Kenneth L

    2003-04-01

    Full Text Available Abstract Background Staphylococcus aureus infection of normal osteoblasts induces expression of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL. Results Normal osteoblasts were incubated in the presence of purified bacterial products over a range of concentrations. Results demonstrate that purified surface structures and a selected superantigen present in the extracellular environment are not capable of inducing TRAIL expression by osteoblasts. Osteoblasts were co-cultured with S. aureus at various multiplicities of infection utilizing cell culture chamber inserts. Results of those experiments suggest that direct contact between bacteria and osteoblasts is necessary for optimal TRAIL induction. Finally, S. aureus infection of osteoblasts in the presence of anti-TRAIL antibody demonstrates that TRAIL mediates caspase-8 activation and apoptosis of infected cells. Conclusions Collectively, these findings suggest a mechanism whereby S. aureus mediates bone destruction via induction of osteoblast apoptosis.

  20. SMARTCyp: A 2D Method for Prediction of Cytochrome P450-Mediated Drug Metabolism.

    Science.gov (United States)

    Rydberg, Patrik; Gloriam, David E; Zaretzki, Jed; Breneman, Curt; Olsen, Lars

    2010-06-10

    SMARTCyp is an in silico method that predicts the sites of cytochrome P450-mediated metabolism of druglike molecules. The method is foremost a reactivity model, and as such, it shows a preference for predicting sites that are metabolized by the cytochrome P450 3A4 isoform. SMARTCyp predicts the site of metabolism directly from the 2D structure of a molecule, without requiring calculation of electronic properties or generation of 3D structures. This is a major advantage, because it makes SMARTCyp very fast. Other advantages are that experimental data are not a prerequisite to create the model, and it can easily be integrated with other methods to create models for other cytochrome P450 isoforms. Benchmarking tests on a database of 394 3A4 substrates show that SMARTCyp successfully identifies at least one metabolic site in the top two ranked positions 76% of the time. SMARTCyp is available for download at http://www.farma.ku.dk/p450.

  1. Interactions of prostaglandin A2 with the glutathione-mediated biotransformation system

    NARCIS (Netherlands)

    Iersel, M.L.P.S. van; Cnubben, N.H.P.; Smink, N.; Koeman, J.H.; Bladeren, P.J. van

    1999-01-01

    The cyclopentenone prostaglandin A2 (PGA2) is known to inhibit cell proliferation, and metabolism of this compound thus might be important in controlling its ultimate function. The glutathione-related metabolism of PGA2 was therefore investigated both with purified glutathione S-transferase P1-1 (GS

  2. Interactions of prostaglandin A2 with the glutathione-mediated biotransformation system

    NARCIS (Netherlands)

    Iersel, M.L.P.S. van; Cnubben, N.H.P.; Smink, N.; Koeman, J.H.; Bladeren, P.J. van

    1999-01-01

    The cyclopentenone prostaglandin A2 (PGA2) is known to inhibit cell proliferation, and metabolism of this compound thus might be important in controlling its ultimate function. The glutathione-related metabolism of PGA2 was therefore investigated both with purified glutathione S-transferase P1-1 (GS

  3. Interactions of prostaglandin A2 with the glutathione-mediated biotransformation system

    NARCIS (Netherlands)

    Iersel, van M.P.L.S.; Cnubben, N.H.P.; Smink, N.; Koeman, J.H.; Bladeren, van P.J.

    1999-01-01

    The cyclopentenone prostaglandin A2 (PGA2) is known to inhibit cell proliferation, and metabolism of this compound thus might be important in controlling its ultimate function. The glutathione-related metabolism of PGA2 was therefore investigated both with purified glutathione S-transferase P1-1

  4. PDGF-AA mediates mesenchymal stromal cell chemotaxis to the head and neck squamous cell carcinoma tumor microenvironment.

    Science.gov (United States)

    Watts, Tammara L; Cui, Ruwen; Szaniszlo, Peter; Resto, Vicente A; Powell, Don W; Pinchuk, Irina V

    2016-12-08

    The robust desmoplasia associated with head and neck squamous cell carcinoma (HNSCC) suggests that the tumor microenvironment may be an important component in the pathophysiology of this cancer. Moreover, the high recurrence rate and poor clinical response to chemotherapy and radiation treatment further underscores that the non-cancerous cells of the microenvironment, such as mesenchymal stromal cells (MSCs), cancer associated fibroblasts (CAFs), and pericytes, may be important in the pathophysiology of HNSCC. Confocal microscopy and immunohistomchemistry approaches were used to identify MSCs tumor microenvironment from patients with oral cavity and oral pharyngeal squamous cell carcinoma (SCC). In vitro Boyden chamber assays and multiplex magnetic bead assays were used to measure MSC chemotaxis and to identify the chemokines secreted by JHU-011, -012, -019, three cells lines derived from patients with oral pharyngeal SCC. We show here that MSCs reside in the tumor microenvironment of patients with oral cavity and oral pharyngeal SCC and are recruited via paracrine mediated tumor cell secretion of (platelet derived growth factor) PDGF-AA. The MSC markers CD90(+), CD105(+), and gremlin-1(+) were found to co-localize on cells within the tumor microenvironment in oral cavity SCC specimens distinct from α-smooth muscle actin staining CAFs. The conditioned media from JHU-011, -012, and -019 caused a significant increase in MSC migration (>60%) and invasion (>50%; p microenvironment expression of PDGFR-α has been shown to correlate with a worse prognosis in patients with prostate, breast, ovarian, non-small cell lung cancer and osteosarcoma. This is the first evidence that a similar signaling paradigm may be present in HNSCC. PDGFR-α inhibitors have not been studied as adjunctive treatment options in the management of HNSCC and may prove to be an important driver of the malignant phenotype in this setting.

  5. Methylglyoxal-Mediated Stress Correlates with High Metabolic Activity and Promotes Tumor Growth in Colorectal Cancer

    Science.gov (United States)

    Chiavarina, Barbara; Nokin, Marie-Julie; Bellier, Justine; Durieux, Florence; Bletard, Noëlla; Sherer, Félicie; Lovinfosse, Pierre; Peulen, Olivier; Verset, Laurine; Dehon, Romain; Demetter, Pieter; Turtoi, Andrei; Uchida, Koji; Goldman, Serge; Hustinx, Roland; Delvenne, Philippe; Castronovo, Vincent; Bellahcène, Akeila

    2017-01-01

    Cancer cells generally rely on aerobic glycolysis as a major source of energy. Methylglyoxal (MG), a dicarbonyl compound that is produced as a side product during glycolysis, is highly reactive and induces the formation of advanced glycation end-products that are implicated in several pathologies including cancer. All mammalian cells have an enzymatic defense against MG composed by glyoxalases GLO1 and GLO2 that converts MG to d-lactate. Colorectal cancer (CRC) is one of the most frequently occurring cancers with high morbidity and mortality. In this study, we used immunohistochemistry to examine the level of MG protein adducts, in a series of 102 CRC human tumors divided into four clinical stages. We consistently detected a high level of MG adducts and low GLO1 activity in high stage tumors compared to low stage ones suggesting a pro-tumor role for dicarbonyl stress. Accordingly, GLO1 depletion in CRC cells promoted tumor growth in vivo that was efficiently reversed using carnosine, a potent MG scavenger. Our study represents the first demonstration that MG adducts accumulation is a consistent feature of high stage CRC tumors. Our data point to MG production and detoxification levels as an important molecular link between exacerbated glycolytic activity and CRC progression. PMID:28117708

  6. Hypoxia-induced down-modulation of PKCepsilon promotes trail-mediated apoptosis of tumor cells.

    Science.gov (United States)

    Gobbi, Giuliana; Masselli, Elena; Micheloni, Cristina; Nouvenne, Antonio; Russo, Domenico; Santi, Patrizia; Matteucci, Alessandro; Cocco, Lucio; Vitale, Marco; Mirandola, Prisco

    2010-09-01

    Tumor oxygen status is considered as a prognostic marker that impacts on malignant progression and outcome of tumor therapy. TNF-related apoptosis inducing ligand (TRAIL) plays a key role in cancer immunity, with potential applications in cancer therapy. Protein kinase C (PKC)epsilon, a transforming oncogene, has a role in the protection of cardiomyocytes and neurons from hypoxia-induced damage while, it can also modulate the susceptibility of tumor cells to TRAIL-induced cell death. Here we demonstrate that hypoxia induces a tumor cell phenotype highly sensitive to the cytotoxic effects of TRAIL. Based on the observation that: i) PKCepsilon expression levels are impaired during hypoxia, ii) the overexpression of PKCepsilon, but not of a kinase-inactive PKCepsilon mutant, is able to revert the hypoxia-induced sensitivity to TRAIL, iii) the down-modulation of PKCepsilon levels by RNA interference, on the contrary, induces the highly TRAIL-sensitive phenotype, iv) the inhibition of hypoxia-inducible transcription factor-1alpha (HIF-1alpha) by specific siRNA blocks both the hypoxia-induced down-modulation of PKCepsilon and the induction of the highly TRAIL-sensitive phenotype; we conclude that the HIF-1alpha upregulation during hypoxia is associated to PKCepsilon down-modulation that likely represents the key molecular event promoting the apoptogenic effects of TRAIL in hypoxic tumor cells.

  7. Efficiency of Conditionally Attenuated Salmonella enterica Serovar Typhimurium in Bacterium-Mediated Tumor Therapy

    Science.gov (United States)

    Frahm, Michael; Kocijancic, Dino; Rohde, Manfred; Hensel, Michael; Curtiss, Roy; Erhardt, Marc; Weiss, Siegfried

    2015-01-01

    ABSTRACT Increasing numbers of cancer cases generate a great urge for new treatment options. Applying bacteria like Salmonella enterica serovar Typhimurium for cancer therapy represents an intensively explored option. These bacteria have been shown not only to colonize solid tumors but also to exhibit an intrinsic antitumor effect. In addition, they could serve as tumor-targeting vectors for therapeutic molecules. However, the pathogenic S. Typhimurium strains used for tumor therapy need to be attenuated for safe application. Here, lipopolysaccharide (LPS) deletion mutants (ΔrfaL, ΔrfaG, ΔrfaH, ΔrfaD, ΔrfaP, and ΔmsbB mutants) of Salmonella were investigated for efficiency in tumor therapy. Of such variants, the ΔrfaD and ΔrfaG deep rough mutants exhibited the best tumor specificity and lowest pathogenicity. However, the intrinsic antitumor effect was found to be weak. To overcome this limitation, conditional attenuation was tested by complementing the mutants with an inducible arabinose promoter. The chromosomal integration of the respective LPS biosynthesis genes into the araBAD locus exhibited the best balance of attenuation and therapeutic benefit. Thus, the present study establishes a basis for the development of an applicably cancer therapeutic bacterium. PMID:25873375

  8. Modulation of the leptin receptor mediates tumor growth and migration of pancreatic cancer cells.

    Science.gov (United States)

    Mendonsa, Alisha M; Chalfant, Madeleine C; Gorden, Lee D; VanSaun, Michael N

    2015-01-01

    Obesity has been implicated as a significant risk factor for development of pancreatic cancer. In the setting of obesity, a systemic chronic inflammatory response is characterized by alterations in the production and secretion of a wide variety of growth factors. Leptin is a hormone whose level increases drastically in the serum of obese patients. High fat diet induced obesity in mice leads to an overall increased body weight, pancreatic weight, serum leptin, and pancreatic tissue leptin levels. Here we report the contribution of obesity and leptin to pancreatic cancer growth utilizing an in vivo orthotopic murine pancreatic cancer model, which resulted in increased tumor proliferation with concomitant increased tumor burden in the diet induced obese mice compared to lean mice. Human and murine pancreatic cancer cell lines were found to express the short as well as the long form of the leptin receptor and functionally responded to leptin induced activation through an increased phosphorylation of AKT473. In vitro, leptin stimulation increased cellular migration which was blocked by addition of a PI3K inhibitor. In vivo, depletion of the leptin receptor through shRNA knockdown partially abrogated increased orthotopic tumor growth in obese mice. These findings suggest that leptin contributes to pancreatic tumor growth through activation of the PI3K/AKT pathway, which promotes pancreatic tumor cell migration.

  9. Modulation of the leptin receptor mediates tumor growth and migration of pancreatic cancer cells.

    Directory of Open Access Journals (Sweden)

    Alisha M Mendonsa

    Full Text Available Obesity has been implicated as a significant risk factor for development of pancreatic cancer. In the setting of obesity, a systemic chronic inflammatory response is characterized by alterations in the production and secretion of a wide variety of growth factors. Leptin is a hormone whose level increases drastically in the serum of obese patients. High fat diet induced obesity in mice leads to an overall increased body weight, pancreatic weight, serum leptin, and pancreatic tissue leptin levels. Here we report the contribution of obesity and leptin to pancreatic cancer growth utilizing an in vivo orthotopic murine pancreatic cancer model, which resulted in increased tumor proliferation with concomitant increased tumor burden in the diet induced obese mice compared to lean mice. Human and murine pancreatic cancer cell lines were found to express the short as well as the long form of the leptin receptor and functionally responded to leptin induced activation through an increased phosphorylation of AKT473. In vitro, leptin stimulation increased cellular migration which was blocked by addition of a PI3K inhibitor. In vivo, depletion of the leptin receptor through shRNA knockdown partially abrogated increased orthotopic tumor growth in obese mice. These findings suggest that leptin contributes to pancreatic tumor growth through activation of the PI3K/AKT pathway, which promotes pancreatic tumor cell migration.

  10. Molecular Imaging of Gene Expression and Efficacy following Adenoviral-Mediated Brain Tumor Gene Therapy

    Directory of Open Access Journals (Sweden)

    Alnawaz Rehemtulla

    2002-01-01

    Full Text Available Cancer gene therapy is an active area of research relying upon the transfer and subsequent expression of a therapeutic transgene into tumor cells in order to provide for therapeutic selectivity. Noninvasive assessment of therapeutic response and correlation of the location, magnitude, and duration of transgene expression in vivo would be particularly useful in the development of cancer gene therapy protocols by facilitating optimization of gene transfer protocols, vector development, and prodrug dosing schedules. In this study, we developed an adenoviral vector containing both the therapeutic transgene yeast cytosine deaminase (yCD along with an optical reporter gene (luciferase. Following intratumoral injection of the vector into orthotopic 9L gliomas, anatomical and diffusion-weighted MR images were obtained over time in order to provide for quantitative assessment of overall therapeutic efficacy and spatial heterogeneity of cell kill, respectively. In addition, bioluminescence images were acquired to assess the duration and magnitude of gene expression. MR images revealed significant reduction in tumor growth rates associated with yCD/5-fluorocytosine (5FC gene therapy. Significant increases in mean tumor diffusion values were also observed during treatment with 5FC. Moreover, spatial heterogeneity in tumor diffusion changes were also observed revealing that diffusion magnetic resonance imaging could detect regional therapeutic effects due to the nonuniform delivery and/or expression of the therapeutic yCD transgene within the tumor mass. In addition, in vivo bioluminescence imaging detected luciferase gene expression, which was found to decrease over time during administration of the prodrug providing a noninvasive surrogate marker for monitoring gene expression. These results demonstrate the efficacy of the yCD/5FC strategy for the treatment of brain tumors and reveal the feasibility of using multimodality molecular and functional imaging

  11. Tumor necrosis factor suppresses NR5A2 activity and intestinal glucocorticoid synthesis to sustain chronic colitis.

    Science.gov (United States)

    Huang, Sheng-Chieh; Lee, Cheng-tse; Chung, Bon-chu

    2014-02-25

    Intestinal crypt epithelial cells synthesize glucocorticoids, steroid hormones that protect against inflammatory bowel disease. To investigate how intestinal glucocorticoids are regulated during chronic inflammation, we induced chronic colitis in mice by exposing them to the chemical dextran sulfate sodium (DSS). We found that intestinal glucocorticoid secretion and expression of the genes Cyp11a1 and Cyp11b1 (which encode enzymes that synthesize glucocorticoids) were initially stimulated, but declined during the chronic phase, whereas tumor necrosis factor (TNF) and inflammatory cytokines secreted by T helper type 1 (TH1) and TH17 cells continuously increased in abundance in the inflamed colon. This suggested that inadequate intestinal glucocorticoid synthesis is a feature of chronic intestinal inflammation. We screened for cytokines that regulated intestinal glucocorticoid synthesis and found that TNF suppressed corticosterone secretion and Cyp11a1 and Cyp11b1 expression in an intestinal crypt epithelial cell line. TNF suppressed steroidogenesis by activating the transcription factors c-Jun and nuclear factor κB (NF-κB), which both interacted with the transcription factor NR5A2 and repressed Cyp11a1 reporter activity. This repression was relieved by expression of a dominant-negative form of c-Jun amino-terminal kinase 1 (JNK1), inhibitor of NF-κB, or by a JNK inhibitor. Furthermore, the dominant-negative TNF inhibitor XPro1595 inhibited c-Jun and NF-κB activation in mice, restored intestinal Cyp11a1 and Cyp11b1 expression, reduced colonic cell death, and rescued chronic colitis caused by DSS. Thus, during chronic colitis, TNF suppresses intestinal steroidogenic gene expression by inhibiting the activity of NR5A2, thus decreasing glucocorticoid synthesis and sustaining chronic inflammation.

  12. Increased brain edema following 5-aminolevulinic acid mediated photodynamic in normal and tumor bearing rats

    Science.gov (United States)

    Hirschberg, Henry; Angell-Petersen, Even; Spetalen, Signe; Mathews, Marlon; Madsen, Steen J.

    2007-02-01

    Introduction: Failure of treatment for high grade gliomas is usually due to local recurrence at the site of surgical resection indicating that a more aggressive form of local therapy, such as PDT, could be of benefit. PDT causes damage to both tumor cells as well as cerebral blood vessels leading to degradation of the blood brain barrier with subsequent increase of brain edema. The increase in brain edema following ALA-PDT was evaluated in terms of animal survival, histopatological changes in normal brain and tumor tissue and MRI scanning. The effect of steroid treatment, to reduce post-treatment PDT induced edema, was also examined. Methods:Tumors were established in the brains of inbred BD-IX and Fisher rats. At various times following tumor induction the animals were injected with ALA ip. and four hours later light treatment at escalating fluences and fluence rates were given. Nontumor bearing control animals were also exposed to ALA-PDT in a similar manner to evaluate damage to normal brain and degree of blood brain barrier (BBB) disruption. Results: Despite a very low level of PpIX production in normal brain, with a 200:1 tumor to normal tissue selectivity ratio measured at a distance of 2 mm from the tumor border, many animals succumbed shortly after treatment. A total radiant energy of 54 J to non-tumor bearing animals resulted in 50% mortality within 5 days of treatment. Treatment of tumor bearing animals with moderate fluence levels produced similar brain edema compared to higher fluence levels. ALA PDT in nontumor bearing animals produced edema that was light dose dependent. PDT appeared to open the BBB for a period of 24-48 hrs after which it was restored. The addition of post operative steroid treatment reduced the incident of post treatment morbidity and mortality. Conclusions: T2 and contrast enhanced T1 MRI scanning proved to be a highly effective and non-evasive modality in following the development of the edema reaction and the degree and time

  13. Synergistic anti-tumor effect of recombinant chicken fibroblast growth factor receptor-1-mediated anti-angiogenesis and low-dose gemcitabine in a mouse colon adenocarcinoma model

    Institute of Scientific and Technical Information of China (English)

    Shao-Jiang Zheng; Shao-Ping Zheng; Feng-Ying Huang; Chang-Liang Jiao; Ren-Liang Wu

    2007-01-01

    AIM: To evaluate whether the combination of recombinant chicken fibroblast growth factor receptor -1(FGFR-1) protein vaccine (cFR-1) combined with low-dose gemcitabine would improve anti-tumor efficacy in a mouse CT26 colon adenocarcinoma (CT26) model.METHODS: The CT26 model was established in BABL/c mice. Seven days after tumor cell injection, mice were randomly divided into four groups: combination therapy,cFR-1 alone, gemcitabine alone, and normal saline groups. Tumor growth, survival rate of tumor-bearing mice, and systemic toxicity were observed. The presence of anti-tumor auto-antibodies was detected by Western blot analysis and enzyme-linked immunospot assay,microvessel density (MVD) of the tumors and tumor cell proliferation were detected by Immunohistochemistry staining, and tumor cell apoptosis was detected by TdT-mediated biotinylated-dUTP nick end label staining.RESULTS: The combination therapy results in apparent decreases in tumor volume, microvessel density and tumor cell proliferation, and an increase in apoptosis without obvious side-effects as compared with either therapy alone or normal control groups. Also, both autoantibodies and the antibody-producing B cells against mouse FGFR-1 were detected in mice immunized with cFR-1 vaccine alone or with combination therapy, but not in non-immunized mice. In addition, the deposition of auto-antibodies on endothelial cells from mice immunized with cFR-1 was observed by immunofluorescent staining, but not on endothelial cells from control groups.Synergistic indexes of tumor volume, MVD, cell apoptosis and proliferation in the combination therapy group were 1.71 vs 1.15 vs 1.11 and 1.04, respectively, 31 d after tumor cell injection.CONCLUSION: The combination of cFR-1-mediated antiangiogenesis and low-dose gemcitabine synergistically enhances the anti-tumor activity without overt toxicity in mice.

  14. HLA-A2–Restricted Cytotoxic T Lymphocyte Epitopes from Human Heparanase as Novel Targets for Broad-Spectrum Tumor Immunotherapy

    Directory of Open Access Journals (Sweden)

    Ting Chen

    2008-09-01

    Full Text Available Peptide vaccination for cancer immunotherapy requires identification of peptide epitopes derived from antigenic proteins associated with tumors. Heparanase (Hpa is broadly expressed in various advanced tumors and seems to be an attractive new tumor-associated antigen. The present study was designed to predict and identify HLA-A2– restricted cytotoxic T lymphocyte (CTL epitopes in the protein of human Hpa. For this purpose, HLA-A2–restricted CTL epitopes were identified using the following four-step procedure: 1 a computer-based epitope prediction from the amino acid sequence of human Hpa, 2 a peptide-binding assay to determine the affinity of the predicted protein with the HLA-A2 molecule, 3 stimulation of the primary T-cell response against the predicted peptides in vitro, and 4 testing of the induced CTLs toward different kinds of carcinoma cells expressing Hpa antigens and/or HLA-A2. The results demonstrated that, of the tested peptides, effectors induced by peptides of human Hpa containing residues 525-533 (PAFSYSFFV, Hpa525, 277-285 (KMLKSFLKA, Hpa277, and 405-413 (WLSLLFKKL, Hpa405 could effectively lyse various tumor cell lines that were Hpa-positive and HLA-A2-matched. We also found that these peptide-specific CTLs could not lyse autologous lymphocytes with low Hpa activity. Further study revealed that Hpa525, Hpa277, and Hpa405 peptides increased the frequency of IFN-γ–producing T cells compared to a negative peptide. Our results suggest that Hpa525, Hpa277, and Hpa405 peptides are new HLA-A2–restricted CTL epitopes capable of inducing Hpa-specific CTLs in vitro. Because Hpa is expressed in most advanced malignant tumors, Hpa525, Hpa277, and Hpa405 peptide–based vaccines may be useful for the immunotherapy for patients with advanced tumors.

  15. IL-7 inhibits tumor growth by promoting T cell-mediated antitumor immunity in Meth A model.

    Science.gov (United States)

    Tang, Jian-Cai; Shen, Guo-Bo; Wang, Shi-Min; Wan, Yong-Sheng; Wei, Yu-Quan

    2014-01-01

    Immune suppression is well documented during tumor progression, which includes loss of effect of T cells and expansion of T regulatory (Treg) cells. IL-7 plays a key role in the proliferation, survival and homeostasis of T cells and displays a potent antitumor activity in vivo. In the present study, we investigated the antitumor effect of IL-7 in Meth A model. IL-7 inhibited tumor growth and prolonged the survival of tumor-bearing mice with corresponding increases in the frequency of CD4 and CD8 T cells, Th1 (CD4(+)IFN-γ(+)), Tc1 (CD8(+)IFN-γ(+)) and T cells cytolytic activity against Meth A cells. Neutralization of CD4 or CD8 T cells reversed the antitumor benefit of IL-7. Furthermore, IL-7 decreased regulatory T Foxp3 as well as cells suppressive activity with a reciprocal increase in SMAD7. In addition, we observed an increase of the serum concentrations of IL-6 and IFN-γ, and a significant decrease of TGF-β and IL-10 after IL-7 treatment. Taken together, these results indicate that IL-7 augments T cell-mediated antitumor immunity and improves the effect of antitumor in Meth A model.

  16. Human dendritic cells mediate cellular apoptosis via tumor necrosis factor-related apoptosis-inducing ligand (TRAIL).

    Science.gov (United States)

    Fanger, N A; Maliszewski, C R; Schooley, K; Griffith, T S

    1999-10-18

    TRAIL (TNF-related apoptosis-inducing ligand) is a member of the TNF family that induces apoptosis in a variety of cancer cells. In this study, we demonstrate that human CD11c(+) blood dendritic cells (DCs) express TRAIL after stimulation with either interferon (IFN)-gamma or -alpha and acquire the ability to kill TRAIL-sensitive tumor cell targets but not TRAIL-resistant tumor cells or normal cell types. The DC-mediated apoptosis was TRAIL specific, as soluble TRAIL receptor blocked target cell death. Moreover, IFN-stimulated interleukin (IL)-3 receptor (R)alpha(+) blood precursor (pre-)DCs displayed minimal cytotoxicity toward the same target cells, demonstrating a clear functional difference between the CD11c(+) DC and IL-3Ralpha(+) pre-DC subsets. These results indicate that TRAIL may serve as an innate effector molecule on CD11c(+) DCs for the elimination of spontaneously arising tumor cells and suggest a means by which TRAIL-expressing DCs may regulate or eliminate T cells responding to antigen presented by the DCs.

  17. Measurement of ventilation- and perfusion-mediated cooling during laser ablation in ex vivo human lung tumors.

    Science.gov (United States)

    Vietze, Andrea; Koch, Franziska; Laskowski, Ulrich; Linder, Albert; Hosten, Norbert

    2011-11-01

    Perfusion-mediated tissue cooling has often been described in the literature for thermal ablation therapies of liver tumors. The objective of this study was to investigate the cooling effects of both perfusion and ventilation during laser ablation of lung malignancies. An ex vivo lung model was used to maintain near physiological conditions for the specimens. Fourteen human lung lobes containing only primary lung tumors (non-small cell lung cancer) were used. Laser ablation was carried out using a Nd:YAG laser with a wavelength of 1064 nm and laser fibers with 30 mm diffusing tips. Continuous invasive temperature measurement in 10 mm distance from the laser fiber was performed. Laser power was increased at 2 W increments starting at 10 W up to a maximum power of 12-20 W until a temperature plateau around 60 °C was reached at one sensor. Ventilation and perfusion were discontinued for 6 min each to assess their effects on temperature development. The experiments lead to 25 usable temperature profiles. A significant temperature increase was observed for both discontinued ventilation and perfusion. In 6 min without perfusion, the temperature rose about 5.5 °C (mean value, Pcooling are significant influencing factors on temperature development during thermal ablation. They should be taken into account during the planning and preparation of minimally invasive lung tumor treatment in order to achieve complete ablation. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  18. Inhibitory effects of benzodiazepines on the adenosine A(2B) receptor mediated secretion of interleukin-8 in human mast cells.

    Science.gov (United States)

    Hoffmann, Kristina; Xifró, Rosa Altarcheh; Hartweg, Julia Lisa; Spitzlei, Petra; Meis, Kirsten; Molderings, Gerhard J; von Kügelgen, Ivar

    2013-01-30

    The activation of adenosine A(2B) receptors in human mast cells causes pro-inflammatory responses such as the secretion of interleukin-8. There is evidence for an inhibitory effect of benzodiazepines on mast cell mediated symptoms in patients with systemic mast cell activation disease. Therefore, we investigated the effects of benzodiazepines on adenosine A(2B) receptor mediated interleukin-8 production in human mast cell leukaemia (HMC1) cells by an enzyme linked immunosorbent assay. The adenosine analogue N-ethylcarboxamidoadenosine (NECA, 0.3-3 μM) increased interleukin-8 production about 5-fold above baseline. This effect was attenuated by the adenosine A(2B) receptor antagonist MRS1754 (N-(4-cyanophenyl)-2-{4-(2,3,6,7-tetrahydro-2,6-dioxo-1,3-dipropyl-1H-purin-8-yl)phenoxy}-acetamide) 1 μM. In addition, diazepam, 4'-chlorodiazepam and flunitrazepam (1-30 μM) markedly reduced NECA-induced interleukin-8 production in that order of potency, whereas clonazepam showed only a modest inhibition. The inhibitory effect of diazepam was not altered by flumazenil 10 μM or PK11195 (1-(2-chlorophenyl)-N-methyl-N-(1-methylpropyl)-3-isoquinolinecarboxamide) 10 μM. Diazepam attenuated the NECA-induced expression of mRNA encoding for interleukin-8. Moreover, diazepam and flunitrazepam reduced the increasing effects of NECA on cAMP-response element- and nuclear factor of activated t-cells-driven luciferase reporter gene activities in HMC1 cells. Neither diazepam nor flunitrazepam affected NECA-induced increases in cellular cAMP levels in CHO Flp-In cells stably expressing recombinant human adenosine A(2B) receptors, excluding a direct action of benzodiazepines on human adenosine A(2B) receptors. In conclusion, this is the first study showing an inhibitory action of benzodiazepines on adenosine A(2B) receptor mediated interleukin-8 production in human mast (HMC1) cells. The rank order of potency indicates the involvement of an atypical benzodiazepine binding site.

  19. Production of phosphatidylcholine containing conjugated linoleic acid mediated by phospholipase A2

    OpenAIRE

    Yamamoto, Yukihiro; Hosokawa, Masashi; Miyashita, Kazuo

    2006-01-01

    Esterification of lysophosphatidylcholine (LPC) with conjugated linoleic acid (CLA) was carried out using porcine pancreatic phospholipase A2 (PLA2). PLA2 only slightly synthesized phosphatidylcholine containing CLA (CLA-PC) at 2.6% by the addition of water. Addition of formamide in place of water markedly increased the yield of CLA-PC. In addition, synthesis of CLA-PC by PLA2 was affected by the amount of substrate CLA and PLA2 in the reaction system. Under optimal reaction conditions using ...

  20. Carboxymethyl-β-cyclodextrin conjugated nanoparticles facilitate therapy for folate receptor-positive tumor with the mediation of folic acid.

    Science.gov (United States)

    Su, Chang; Li, Hongdan; Shi, Yijie; Wang, Guan; Liu, Liwei; Zhao, Liang; Su, Rongjian

    2014-10-20

    Currently, clinical operation treatments, chemotherapy and radiotherapy just could eliminate local tumor cells. However, chemotherapy and radiotherapy also injury normal cells and lead to serious side effects and toxicities. So, it is necessary to find an effective target cancer carrier that delivers the anticancer agents into tumor cells and reduces normal cells' injury. Folic acid (FA) is a classical targeting agent mediates internalization of chemical drugs into tumor cells which over-express folate receptor (FR) on their surface. We herein report that based on host-guest interaction, NPs decorated by novel folate enhance antitumor drug delivery. BSA-NPs were prepared by desolvation method and carboxymethyl-β-cyclodextrin (CM-β-CD) was conjugated to the surface of NPs by carbodiimide coupling to hold FA. From in vitro cytotoxicity assay, cell apoptosis study, intracellular ATP level assay and western blot, we can see that FA-CM-β-CD-BSA NPs as good monodispersity, negative charge, and homogenous particle size have a high encapsulation efficiency. The results showed that MTT and cell apoptosis demonstrated that FA-decorated NPs exhibit stronger inhibition rate and induce obvious apoptosis in FR positive Hela cells as compared to free drug and FA undecorated NPs. Moreover, 5-fluorouracil (5-Fu) loaded FA-CM-β-CD-BSA NPs down-regulate ATP levels and increase the expression of caspase-3. Taken together, FA-CM-β-CD-BSA NPs enhance FR receptor-mediated endocytosis and lead to more intracellular uptake of drug, inducing the higher apoptosis ratio of cells than free 5-Fu.

  1. NF-KB downregulation may be involved the depression of tumor cell proliferation mediated by human mesenchymal stem cells

    Institute of Scientific and Technical Information of China (English)

    Ling QIAO; Tie-jun ZHAO; Feng-ze WANG; Chang-liang SHAN; Li-hong YE; Xiao-dong ZHANG

    2008-01-01

    Aim:It has been reported that stem cells are able to home to tumorigenesis and inhibit the proliferation of tumor cells.The purpose of our study was to demon-strate the molecular mechanism of the inhibitory proliferation of hepatoma cells and breast cancer cells mediated by human mesenchymal stem cells (hMSCs).Methods:The proliferation of H7402 human hepatoma cells and MCF-7 human breast cancer cells was measured by the 5-bromodeoxyuridine (BrdU) incorpora-tion assay and flow cytometry assay after the treatment with conditioned media from hMSCs culture,such as Z3 cells or BMMS-03 cells.The role of NF-kB or the phosphorylation of inhibitor kBoα (p-IkBα) in the depression of hepatoma or breast cancer cells treated with conditioned media from Z3 cells or BMMS-03 cells was examined by reporter gene assay,quantitative real-time PCR,and Western blot analysis,respectively.Results:The proliferation of H7402 cells and MCF-7 cells was decreased significantly by the BrdU incorporation assay and flow cytometry assay after treatment.The transcriptional activity and mRNA level of NF-kB were downregulated in the treated cells by reporter gene assay and quantitative real-time PCR in a dose-dependent manner.At the protein level,NF-kB and p-IkBα decreased in the treated cells by Western blot analysis.Conclusion:Conditioned media from hMSCs are able to inhibit the proliferation of tumor cells.NF-kB downregulation is one of reasons for the depression of tumor cell proliferation mediated by hMSCs.

  2. FASN Inhibition and Taxane Treatment Combine to Enhance Anti-tumor Efficacy in Diverse Xenograft Tumor Models through Disruption of Tubulin Palmitoylation and Microtubule Organization and FASN Inhibition-Mediated Effects on Oncogenic Signaling and Gene Expression.

    Science.gov (United States)

    Heuer, Timothy S; Ventura, Richard; Mordec, Kasia; Lai, Julie; Fridlib, Marina; Buckley, Douglas; Kemble, George

    2017-02-01

    Palmitate, the enzymatic product of FASN, and palmitate-derived lipids support cell metabolism, membrane architecture, protein localization, and intracellular signaling. Tubulins are among many proteins that are modified post-translationally by acylation with palmitate. We show that FASN inhibition with TVB-3166 or TVB-3664 significantly reduces tubulin palmitoylation and mRNA expression. Disrupted microtubule organization in tumor cells is an additional consequence of FASN inhibition. FASN inhibition combined with taxane treatment enhances inhibition of in vitro tumor cell growth compared to treatment with either agent alone. In lung, ovarian, prostate, and pancreatic tumor xenograft studies, FASN inhibition and paclitaxel or docetaxel combine to inhibit xenograft tumor growth with significantly enhanced anti-tumor activity. Tumor regression was observed in 3 of 6 tumor xenograft models. FASN inhibition does not affect cellular taxane concentration in vitro. Our data suggest a mechanism of enhanced anti-tumor activity of the FASN and taxane drug combination that includes inhibition of tubulin palmitoylation and disruption of microtubule organization in tumor cells, as well as a sensitization of tumor cells to FASN inhibition-mediated effects that include gene expression changes and inhibition of β-catenin. Together, the results strongly support investigation of combined FASN inhibition and taxane treatment as a therapy for a variety of human cancers. Copyright © 2016 3-V Biosciences. Published by Elsevier B.V. All rights reserved.

  3. FASN Inhibition and Taxane Treatment Combine to Enhance Anti-tumor Efficacy in Diverse Xenograft Tumor Models through Disruption of Tubulin Palmitoylation and Microtubule Organization and FASN Inhibition-Mediated Effects on Oncogenic Signaling and Gene Expression

    Directory of Open Access Journals (Sweden)

    Timothy S. Heuer

    2017-02-01

    Full Text Available Palmitate, the enzymatic product of FASN, and palmitate-derived lipids support cell metabolism, membrane architecture, protein localization, and intracellular signaling. Tubulins are among many proteins that are modified post-translationally by acylation with palmitate. We show that FASN inhibition with TVB-3166 or TVB-3664 significantly reduces tubulin palmitoylation and mRNA expression. Disrupted microtubule organization in tumor cells is an additional consequence of FASN inhibition. FASN inhibition combined with taxane treatment enhances inhibition of in vitro tumor cell growth compared to treatment with either agent alone. In lung, ovarian, prostate, and pancreatic tumor xenograft studies, FASN inhibition and paclitaxel or docetaxel combine to inhibit xenograft tumor growth with significantly enhanced anti-tumor activity. Tumor regression was observed in 3 of 6 tumor xenograft models. FASN inhibition does not affect cellular taxane concentration in vitro. Our data suggest a mechanism of enhanced anti-tumor activity of the FASN and taxane drug combination that includes inhibition of tubulin palmitoylation and disruption of microtubule organization in tumor cells, as well as a sensitization of tumor cells to FASN inhibition-mediated effects that include gene expression changes and inhibition of β-catenin. Together, the results strongly support investigation of combined FASN inhibition and taxane treatment as a therapy for a variety of human cancers.

  4. Killing of Brain Tumor Cells by Hypoxia-Responsive Element Mediated Expression of BAX

    Directory of Open Access Journals (Sweden)

    Hangjun Ruan

    1999-11-01

    Full Text Available The presence of radioresistant hypoxic cells in human brain tumors limits the overall effectiveness of conventional fractionated radiation therapy. Tumor-specific therapies that target hypoxic cells are clearly needed. We have investigated the expression of suicide genes under hypoxia by a hypoxia-responsive element (HRE, which can be activated through hypoxia-inducible factor-1 (HIF-1. We transfected plasmids containing multiple copies of HIRE into U-87 MG and U-251 MG-NCI human brain tumor cells and tested their ability to induce LacZ gene expression under anoxia. Gene expression under anoxia versus oxia was increased about 12-fold for U-87 MG cells and about fourfold for U-251 MG-NCI cells. At intermediate hypoxic conditions, increased LacZ gene expression in U-87 MG cells was induced by the plasmid that contained three HREs, but not by the plasmid with two HREs. Lastly, when we placed a suicide gene BAX under the control of HREs, cells transfected with the BAX plasmids were preferentially killed through apoptosis under anoxia. Our studies demonstrate that HRE-regulated gene expression is active in brain tumor cells, and that the amount of increased gene expression obtained is dependent on the cell line, the HIRE copy number, and the degree of hypoxia.

  5. Granzymes are essential for natural killer cell-mediated and perf-facilitated tumor control

    National Research Council Canada - National Science Library

    Pardo, Julián; Balkow, Sandra; Anel, Alberto; Simon, Markus M

    2002-01-01

    ... in the presence of both, perf and gzm. However, recent work using mice deficient in either gzmA, gzmB or both gzm suggested that only perf but neither of the two gzm are critical for tumor surveillance by CTL or NK cells...

  6. HIF-1α mediates tumor hypoxia to confer a perpetual mesenchymal phenotype for malignant progression.

    Science.gov (United States)

    Yoo, Young-Gun; Christensen, Jared; Gu, Jie; Huang, L Eric

    2011-06-21

    Although tumor progression involves genetic and epigenetic alterations to normal cellular biology, the underlying mechanisms of these changes remain obscure. Numerous studies have shown that hypoxia-inducible factor 1α (HIF-1α) is overexpressed in many human cancers and up-regulates a host of hypoxia-responsive genes for cancer growth and survival. We recently identified an alternative mechanism of HIF-1α function that induces genetic alterations by suppressing DNA repair. Here, we show that long-term hypoxia, which mimics the tumor microenvironment, drives a perpetual epithelial-mesenchymal transition (EMT) through up-regulation of the zinc finger E-box binding homeobox protein ZEB2, whereas short-term hypoxia induces a reversible EMT that requires the transcription factor Twist1. Moreover, we show that the perpetual EMT driven by chronic hypoxia depends on HIF-1α induction of genetic alterations rather than its canonical transcriptional activator function. These mesenchymal tumor cells not only acquire tumorigenicity but also display characteristics of advanced cancers, including necrosis, aggressive invasion, and metastasis. Hence, these results reveal a mechanism by which HIF-1α promotes a perpetual mesenchymal phenotype, thereby advancing tumor progression.

  7. Electromobility of plasmid DNA in tumor tissues during electric field-mediated gene delivery.

    Science.gov (United States)

    Zaharoff, D A; Barr, R C; Li, C-Y; Yuan, F

    2002-10-01

    Interstitial transport is a crucial step in plasmid DNA-based gene therapy. However, interstitial diffusion of large nucleic acids is prohibitively slow. Therefore, we proposed to facilitate interstitial transport of DNA via pulsed electric fields. To test the feasibility of this approach to gene delivery, we developed an ex vivo technique to quantify the magnitude of DNA movement due to pulsed electric fields in two tumor tissues: B16.F10 (a mouse melanoma) and 4T1 (a mouse mammary carcinoma). When the pulse duration and strength were 50 ms and 233 V/cm, respectively, we found that the average plasmid DNA movements per 10 pulses were 1.47 microm and 0.35 microm in B16.F10 and 4T1 tumors, respectively. The average plasmid DNA movements could be approximately tripled, ie to reach 3.69 microm and 1.01 microm, respectively, when the pulse strength was increased to 465 V/cm. The plasmid DNA mobility was correlated with the tumor collagen content, which was approximately eight times greater in 4T1 than in B16.F10 tumors. These data suggest that electric field can be a powerful driving force for improving interstitial transport of DNA during gene delivery.

  8. Tissue-specific transplantation antigen P35B (TSTA3) immune response-mediated metabolism coupling cell cycle to postreplication repair network in no-tumor hepatitis/cirrhotic tissues (HBV or HCV infection) by biocomputation.

    Science.gov (United States)

    Wang, Lin; Huang, Juxiang; Jiang, Minghu; Lin, Hong

    2012-06-01

    We constructed the low-expression tissue-specific transplantation antigen P35B (TSTA3) immune response-mediated metabolism coupling cell cycle to postreplication repair network in no-tumor hepatitis/cirrhotic tissues (HBV or HCV infection) compared with high-expression (fold change ≥ 2) human hepatocellular carcinoma in GEO data set, by using integration of gene regulatory network inference method with gene ontology analysis of TSTA3-activated up- and downstream networks. Our results showed TSTA3 upstream-activated CCNB2, CKS1B, ELAVL3, GAS7, NQO1, NTN1, OCRL, PLA2G1B, REG3A, SSTR5, etc. and TSTA3 downstream-activated BAP1, BRCA1, CCL20, MCM2, MS4A2, NTN1, REG1A, TP53I11, VCAN, SLC16A3, etc. in no-tumor hepatitis/cirrhotic tissues. TSTA3-activated network enhanced the regulation of apoptosis, cyclin-dependent protein kinase activity, cell migration, insulin secretion, transcription, cell division, cell proliferation, DNA replication, postreplication repair, cell differentiation, T-cell homeostasis, neutrophil-mediated immunity, neutrophil chemotaxis, interleukin-8 production, inflammatory response, immune response, B-cell activation, humoral immune response, actin filament organization, xenobiotic metabolism, lipid metabolism, phospholipid metabolism, leukotriene biosynthesis, organismal lipid catabolism, phosphatidylcholine metabolism, arachidonic acid secretion, activation of phospholipase A2, deoxyribonucleotide biosynthesis, heterophilic cell adhesion, activation of MAPK activity, signal transduction by p53 class mediator resulting in transcription of p21 class mediator, G-protein-coupled receptor protein signaling pathway, response to toxin, acute-phase response, DNA damage response, intercellular junction assembly, cell communication, and cell recognition, as a result of inducing immune response-mediated metabolism coupling cell cycle to postreplication repair in no-tumor hepatitis/cirrhotic tissues.

  9. Cationic lipid guided short-hairpin RNA interference of annexin A2 attenuates tumor growth and metastasis in a mouse lung cancer stem cell model.

    Science.gov (United States)

    Andey, Terrick; Marepally, Srujan; Patel, Apurva; Jackson, Tanise; Sarkar, Shubhashish; O'Connell, Malaney; Reddy, Rakesh C; Chellappan, Srikumar; Singh, Pomila; Singh, Mandip

    2014-06-28

    The role of side populations (SP) or cancer stem-like cells (CSC) in promoting the resistance phenotype presents a viable anticancer target. Human-derived H1650 SP cells over-express annexin A2 (AnxA2) and SOX2, and are resistant to conventional cytotoxic chemotherapeutics. AnxA2 and SOX2 bind to proto-oncogenes, c-Myc and c-Src, and AnxA2 forms a functional heterotetramer with S100A10 to promote tumor motility. However, the combined role of AnxA2, S100A10 and SOX2 in promoting the resistant phenotype of SP cells has not been investigated. In the current studies, we examined for the first time a possible role of AnxA2 in regulating SA100A10 and SOX2 in promoting a resistant phenotype of lung tumors derived from H1650 SP cells. The resistance of H1650 SP cells to chemotherapy compared to H1650 MP cells was investigated by cell viability studies. A short hairpin RNA targeting AnxA2 (shAnxA2) was formulated in a liposomal (cationic ligand-guided, CLG) carrier and characterized for size, charge and entrapment and loading efficiencies; CLG carrier uptake by H1650 SP cells was demonstrated by fluorescence microscopy, and knockdown of AnxA2 confirmed by qRT-PCR and Western blot. Targeting of xenograft and orthotopic lung tumors was demonstrated with fluorescent (DiR) CLG carriers in mice. The therapeutic efficacy of CLG-AnxA2, compared to that of placebo, was investigated after 2 weeks of treatment in terms of tumor weights and tumor burden in vivo. Compared to mixed population cells, H1650 SP cells showed exponential resistance to docetaxel (15-fold), cisplatin (13-fold), 5-fluorouracil (31-fold), camptothecin (7-fold), and gemcitabine (16-fold). CLG carriers were nanoparticulate (199nm) with a slight positive charge (21.82mV); CLG-shAnx2 was of similar size (217nm) with decreased charge (12.11mV), and entrapment and loading efficiencies of 97% and 6.13% respectively. Fluorescence microscopy showed high uptake of CLG-shAnxA2 in H1650 SP cells after 2h resulting in a 6

  10. F-Box Protein FBXO22 Mediates Polyubiquitination and Degradation of CD147 to Reverse Cisplatin Resistance of Tumor Cells

    Directory of Open Access Journals (Sweden)

    Bo Wu

    2017-01-01

    Full Text Available Drug resistance remains a major clinical obstacle to successful treatment of cancer. As posttranslational modification is becoming widely recognized to affect the function of oncoproteins, targeting specific posttranslational protein modification provides an attractive strategy for anticancer drug development. CD147 is a transmembrane glycoprotein contributing to chemo-resistance of cancer cells in a variety of human malignancies. Ubiquitination is an important posttranslational modification mediating protein degradation. Degradation of oncoproteins, CD147 included, emerges as an attractive alternative for tumor inhibition. However, the ubiquitination of CD147 remains elusive. Here in this study, we found that deletion of the CD147 intracellular domain (CD147-ICD prolonged the half-life of CD147 in HEK293T cells, and we identified that CD147-ICD interacts with FBXO22 using mass spectrometry and Western blot. Then, we demonstrated that FBXO22 mediates the polyubiquitination and degradation of CD147 by recognizing CD147-ICD. While knocking down of FBXO22 prolonged the half-life of CD147 in HEK293T cells, we found that FBXO22 regulates CD147 protein turnover in SMMC-7721, Huh-7 and A549 cells. Moreover, we found that the low level of FBXO22 contributes to the accumulation of CD147 and thereafter the cisplatin resistance of A549/DDP cells. To conclude, our study demonstrated that FBXO22 mediated the polyubiquitination and degradation of CD147 by interacting with CD147-ICD, and CD147 polyubiquitination by FBXO22 reversed cisplatin resistance of tumor cells.

  11. F-Box Protein FBXO22 Mediates Polyubiquitination and Degradation of CD147 to Reverse Cisplatin Resistance of Tumor Cells

    Science.gov (United States)

    Wu, Bo; Liu, Zhen-Yu; Cui, Jian; Yang, Xiang-Min; Jing, Lin; Zhou, Yang; Chen, Zhi-Nan; Jiang, Jian-Li

    2017-01-01

    Drug resistance remains a major clinical obstacle to successful treatment of cancer. As posttranslational modification is becoming widely recognized to affect the function of oncoproteins, targeting specific posttranslational protein modification provides an attractive strategy for anticancer drug development. CD147 is a transmembrane glycoprotein contributing to chemo-resistance of cancer cells in a variety of human malignancies. Ubiquitination is an important posttranslational modification mediating protein degradation. Degradation of oncoproteins, CD147 included, emerges as an attractive alternative for tumor inhibition. However, the ubiquitination of CD147 remains elusive. Here in this study, we found that deletion of the CD147 intracellular domain (CD147-ICD) prolonged the half-life of CD147 in HEK293T cells, and we identified that CD147-ICD interacts with FBXO22 using mass spectrometry and Western blot. Then, we demonstrated that FBXO22 mediates the polyubiquitination and degradation of CD147 by recognizing CD147-ICD. While knocking down of FBXO22 prolonged the half-life of CD147 in HEK293T cells, we found that FBXO22 regulates CD147 protein turnover in SMMC-7721, Huh-7 and A549 cells. Moreover, we found that the low level of FBXO22 contributes to the accumulation of CD147 and thereafter the cisplatin resistance of A549/DDP cells. To conclude, our study demonstrated that FBXO22 mediated the polyubiquitination and degradation of CD147 by interacting with CD147-ICD, and CD147 polyubiquitination by FBXO22 reversed cisplatin resistance of tumor cells. PMID:28117675

  12. Adeno-associated virus mediated endostatin gene therapy in combination with topoisomerase inhibitor effectively controls liver tumor in mouse model

    Institute of Scientific and Technical Information of China (English)

    Sung Yi Hong; Myun Hee Lee; Kyung Sup Kim; Hyun Cheol Jung; Jae Kyung Roh; Woo Jin Hyung; Sung Hoon Noh; Seung Ho Choi

    2004-01-01

    AIM: rAAV mediated endostatin gene therapy has been examined as a new method for treating cancer. However,a sustained and high protein delivery is required to achieve the desired therapeutic effects. We evaluated the impact of topoisomerase inhibitors in rAAV delivered endostatin gene therapy in a liver tumor model.METHODS: rAAV containing endostatin expression cassettes were transduced into hepatoma cell lines. To test whether the topoisomerase inhibitor pretreatment increased the expression of endostatin, Western blotting and ELISA were performed. The biologic activity of endostatin was confirmed by endothelial cell proliferation and tube formation assays.The anti-tumor effects of the rAAV-endostatin vector combined with a topoisomerase inhibitor, etoposide, were evaluated in a mouse liver tumor model.RESULTS: Topoisomerase inhibitors, including camptothecin and etoposide, were found to increase the endostatin expression level in vitro. The over-expressed endostatin,as a result of pretreatment with a topoisomerase inhibitor,was also biologically active. In animal experiments, the combined therapy of topoisomerase inhibitor, etoposide with the rAAV-endostatin vector had the best tumorsuppressive effect and tumor foci were barely observed in livers of the treated mice. Pretreatment with an etoposide increased the level of endostatin in the liver and serum of rAAV-endostatin treated mice. Finally, the mice treated with rAAV-endostatin in combination with etoposide showed the longest survival among the experimental models.CONCLUSION: rAAV delivered endostatin gene therapy in combination with a topoisomerase inhibitor pretreatment is an effective modality for anticancer gene therapy.

  13. Elevation of c-MYC Disrupts HLA Class II-mediated Immune Recognition of Human B-cell Tumors1

    Science.gov (United States)

    God, Jason M.; Cameron, Christine; Figueroa, Janette; Amria, Shereen; Hossain, Azim; Kempkes, Bettina; Bornkamm, Georg W.; Stuart, Robert K.; Blum, Janice S.; Haque, Azizul

    2014-01-01

    Elevated levels of the transcription factor c-myc are strongly associated with various cancers, and in particular B-cell lymphomas. While many of c-MYC’s functions have been elucidated, its effect on the presentation of antigen (Ag) through the HLA class II pathway has not previously been reported. This is an issue of considerable importance, given the low immunogenicity of many c-MYC-positive tumors. We report here that increased c-MYC expression has a negative effect on the ability of B-cell lymphomas to functionally present Ags/peptides to CD4+ T cells. This defect was associated with alterations in the expression of distinct co-factors as well as interactions of antigenic peptides with class II molecules required for the presentation of class II-peptide complexes and T cell engagement. Using early passage Burkitt’s lymphoma (BL) tumors and transformed cells, we show that compared to B-lymphoblasts, BL cells express decreased levels of the class II editor HLA-DM, lysosomal thiol-reductase GILT, and a 47kDa enolase-like protein. Functional Ag presentation was partially restored in BL cells treated with a c-MYC inhibitor, demonstrating the impact of this oncogene on Ag recognition. This restoration of HLA class II-mediated Ag presentation in early passage BL tumors/cells was linked to enhanced HLA-DM expression and a concurrent decrease in HLA-DO in BL cells. Taken together, these results reveal c-MYC exerts suppressive effects at several critical checkpoints in Ag presentation which contribute to the immunoevasive properties of BL tumors. PMID:25595783

  14. Elevation of c-MYC disrupts HLA class II-mediated immune recognition of human B cell tumors.

    Science.gov (United States)

    God, Jason M; Cameron, Christine; Figueroa, Janette; Amria, Shereen; Hossain, Azim; Kempkes, Bettina; Bornkamm, Georg W; Stuart, Robert K; Blum, Janice S; Haque, Azizul

    2015-02-15

    Elevated levels of the transcription factor c-myc are strongly associated with various cancers, and in particular B cell lymphomas. Although many of c-MYC's functions have been elucidated, its effect on the presentation of Ag through the HLA class II pathway has not been reported previously. This is an issue of considerable importance, given the low immunogenicity of many c-MYC-positive tumors. We report in this paper that increased c-MYC expression has a negative effect on the ability of B cell lymphomas to functionally present Ags/peptides to CD4(+) T cells. This defect was associated with alterations in the expression of distinct cofactors as well as interactions of antigenic peptides with class II molecules required for the presentation of class II-peptide complexes and T cell engagement. Using early passage Burkitt's lymphoma (BL) tumors and transformed cells, we show that compared with B lymphoblasts, BL cells express decreased levels of the class II editor HLA-DM, lysosomal thiol-reductase GILT, and a 47-kDa enolase-like protein. Functional Ag presentation was partially restored in BL cells treated with a c-MYC inhibitor, demonstrating the impact of this oncogene on Ag recognition. This restoration of HLA class II-mediated Ag presentation in early passage BL tumors/cells was linked to enhanced HLA-DM expression and a concurrent decrease in HLA-DO in BL cells. Taken together, these results reveal c-MYC exerts suppressive effects at several critical checkpoints in Ag presentation, which contribute to the immunoevasive properties of BL tumors.

  15. Toll-like Receptor 4 Mediates Morphine-Induced Neuroinflammation and Tolerance via Soluble Tumor Necrosis Factor Signaling.

    Science.gov (United States)

    Eidson, Lori N; Inoue, Kiyoshi; Young, Larry J; Tansey, Malu G; Murphy, Anne Z

    2017-02-01

    Opioid tolerance and the potential for addiction is a significant burden associated with pain management, yet its precise underlying mechanism and prevention remain elusive. Immune signaling contributes to the decreased efficacy of opioids, and we recently demonstrated that Toll-like receptor 4 (TLR4)-mediated neuroinflammation in the periaqueductal gray (PAG) drives tolerance. Tumor necrosis factor (TNF), a product of TLR4 signaling, promotes inflammation and facilitates glutamatergic signaling, key components of opioid tolerance. Therefore, we hypothesize that TLR4-mediated opioid tolerance requires TNF signaling. By expression of a dominant-negative TNF peptide via lentiviral vector injection in rat PAG to sequester soluble TNF (solTNF), we demonstrate that solTNF mediates morphine tolerance induced by TLR4 signaling, stimulates neuroinflammation (increased IL-1β and TLR4 mRNA), and disrupts glutamate reuptake (decreased GLT-1 and GLAST mRNA). We further demonstrate the efficacy of the brain-permeant PEGylated version of the anti-solTNF peptide, XPro1595, injected systemically, to normalize morphine-induced CNS neuroinflammation and morphine- and endotoxin-induced changes in glutamate transport, effectively preserving the efficacy of morphine analgesia and eliminating tolerance. Our findings provide a novel pharmacological target for the prevention of opioid-induced immune signaling, tolerance, and addiction.

  16. Status epilepticus induces vasogenic edema via tumor necrosis factor-α/ endothelin-1-mediated two different pathways.

    Directory of Open Access Journals (Sweden)

    Ji-Eun Kim

    Full Text Available Status epilepticus (SE induces vasogenic edema in the piriform cortex with disruptions of the blood-brain barrier (BBB. However, the mechanisms of vasogenic edema formation following SE are still unknown. Here we investigated the endothelin B (ETB receptor-mediated pathway of SE-induced vasogenic edema. Following SE, the release of tumor necrosis factor-α (TNF-α stimulated endothelin-1 (ET-1 release and expression in neurons and endothelial cells. In addition, TNF-α-induced ET-1 increased BBB permeability via ETB receptor-mediated endothelial nitric oxide synthase (eNOS activation in endothelial cells. ETB receptor activation also increased intracellular reactive oxygen species by NADPH oxidase production in astrocytes. These findings suggest that SE results in BBB dysfunctions via endothelial-astroglial interactions through the TNF-α-ET-1-eNOS/NADPH oxidase pathway, and that these ETB receptor-mediated interactions may be an effective therapeutic strategy for vasogenic edema in various neurological diseases.

  17. Suppression of human colon tumor growth by adenoviral vector-mediated NK4 expression in an athymic mouse model

    Institute of Scientific and Technical Information of China (English)

    Jian-Zheng Jie; Jian-Wei Wang; Jian-Guo Qu; Tao Hung

    2007-01-01

    AIM: To investigate the suppressive effects of adenoviral vector-mediated expression of NK4, an antagonist of hepatocyte growth factor (HGF), on human colon cancer in an athymic mouse model to explore the possibility of applying NK4 to cancer gene therapy.METHODS: A human colon tumor model was developed by subcutaneous implantation of tumor tissue formed by LS174T cells grown in athymic mice. Fifteen tumorbearing mice were randomized into three groups (n = 5in each group) at d 3 after tumor implantation and mice were injected intratumorally with phosphate-buffered saline (PBS) or with recombinant adenovirus expressing β-galactosidase (Ad-LacZ) or NK4 (rvAdCMV/NK4) at a 6-d interval for total 5 injections in each mouse. Tumor sizes were measured during treatment to draw a tumor growth curve. At d 26 after the first treatment, all animals were sacrificed and the tumors were removed to immunohistochemically examine proliferating cell nuclear antigen (PCNA), microvessel density (represented by CD31), and apoptotic cells. In a separate experiment,15 additional athymic mice were employed to develop a tumor metastasis model by intraperitoneal injection(ip) of LS174T cells. These mice were randomized into 3 groups (n = 5 in each group) at d 1 after injection and were treated by ip injection of PBS, or Ad-LacZ, or rvAdCMV/NK4 at a 6-d interval for total two injections in each mouse. All animals were sacrificed at d 14 and the numbers and weights of disseminated tumors within the abdominal cavity were measured.RESULTS: Growth of human colon tumors were significantly suppressed in the athymic mice treated with rvAdCMV/NK4 (2537.4±892.3 mm3) compared to those treated by either PBS (5175.2±1228.6 mm3)or Ad-LacZ (5578.8±1955.7 mm3) (P<0.05). The tumor growth inhibition rate was as high as 51%.Immunohistochemical staining revealed a similar PCNA labeling index (75.1%±11.2% in PBS group vs 72.8%±7.6% in Ad-LacZ group vs 69.3%±9.4% in rvAdCMV/NK4 group) in all groups, but

  18. Nanoparticle-mediated binning and profiling of heterogeneous circulating tumor cell subpopulations.

    Science.gov (United States)

    Mohamadi, Reza M; Besant, Justin D; Mepham, Adam; Green, Brenda; Mahmoudian, Laili; Gibbs, Thaddeus; Ivanov, Ivaylo; Malvea, Anahita; Stojcic, Jessica; Allan, Alison L; Lowes, Lori E; Sargent, Edward H; Nam, Robert K; Kelley, Shana O

    2015-01-02

    The analysis of circulating tumor cells (CTCs) is an important capability that may lead to new approaches for cancer management. CTC capture devices developed to date isolate a bulk population of CTCs and do not differentiate subpopulations that may have varying phenotypes with different levels of clinical relevance. Here, we present a new device for CTC spatial sorting and profiling that sequesters blood-borne tumor cells with different phenotypes into discrete spatial bins. Validation data are presented showing that cancer cell lines with varying surface expression generate different binning profiles within the device. Working with patient blood samples, we obtain profiles that elucidate the heterogeneity of CTC populations present in cancer patients and also report on the status of CTCs within the epithelial-to-mesenchymal transition (EMT).

  19. Integrative Modeling Reveals Annexin A2-mediated Epigenetic Control of Mesenchymal Glioblastoma.

    Science.gov (United States)

    Kling, Teresia; Ferrarese, Roberto; Ó hAilín, Darren; Johansson, Patrik; Heiland, Dieter Henrik; Dai, Fangping; Vasilikos, Ioannis; Weyerbrock, Astrid; Jörnsten, Rebecka; Carro, Maria Stella; Nelander, Sven

    2016-10-01

    Glioblastomas are characterized by transcriptionally distinct subtypes, but despite possible clinical relevance, their regulation remains poorly understood. The commonly used molecular classification systems for GBM all identify a subtype with high expression of mesenchymal marker transcripts, strongly associated with invasive growth. We used a comprehensive data-driven network modeling technique (augmented sparse inverse covariance selection, aSICS) to define separate genomic, epigenetic, and transcriptional regulators of glioblastoma subtypes. Our model identified Annexin A2 (ANXA2) as a novel methylation-controlled positive regulator of the mesenchymal subtype. Subsequent evaluation in two independent cohorts established ANXA2 expression as a prognostic factor that is dependent on ANXA2 promoter methylation. ANXA2 knockdown in primary glioblastoma stem cell-like cultures suppressed known mesenchymal master regulators, and abrogated cell proliferation and invasion. Our results place ANXA2 at the apex of a regulatory cascade that determines glioblastoma mesenchymal transformation and validate aSICS as a general methodology to uncover regulators of cancer subtypes.

  20. Immobilized surfactant-nanotube complexes support selectin-mediated capture of viable circulating tumor cells in the absence of capture antibodies.

    Science.gov (United States)

    Mitchell, Michael J; Castellanos, Carlos A; King, Michael R

    2015-10-01

    The metastatic spread of tumor cells from the primary site to anatomically distant organs leads to a poor patient prognosis. Increasing evidence has linked adhesive interactions between circulating tumor cells (CTCs) and endothelial cells to metastatic dissemination. Microscale biomimetic flow devices hold promise as a diagnostic tool to isolate CTCs and develop metastatic therapies, utilizing E-selectin (ES) to trigger the initial rolling adhesion of tumor cells under flow. To trigger firm adhesion and capture under flow, such devices also typically require antibodies against biomarkers thought to be expressed on CTCs. This approach is challenged by the fact that CTCs are now known to exhibit heterogeneous expression of conventional biomarkers. Here, we describe surfactant-nanotube complexes to enhance ES-mediated capture and isolation of tumor cells without the use of capture antibodies. While the majority of tumor cells exhibited weaker rolling adhesion on halloysite nanotubes (HNT) coated with ES, HNT functionalization with the sodium dodecanoate (NaL) surfactant induced a switch to firm cellular adhesion under flow. Conversely, surfactant-nanotube complexes significantly reduced the number of primary human leukocytes captured via ES-mediated adhesion under flow. The switch in tumor cell adhesion was exploited to capture and isolate tumor cells in the absence of EpCAM antibodies, commonly utilized as the gold standard for CTC isolation. Additionally, HNT-NaL complexes were shown to capture tumor cells with low to negligible EpCAM expression, that are not efficiently captured using conventional approaches.

  1. Combining Cytotoxic and Immune-Mediated Gene Therapy to Treat Brain Tumors

    OpenAIRE

    Curtin, James; King, Gwendalyn; Candolfi, Marianela; Greeno, Remy; Kroeger, Kurt; Lowenstein, Pedro; Castro,Maria

    2005-01-01

    Glioblastoma (GBM) is a type of intracranial brain tumor, for which there is no cure. In spite of advances in surgery, chemotherapy and radiotherapy, patients die within a year of diagnosis. Therefore, there is a critical need to develop novel therapeutic approaches for this disease. Gene therapy, which is the use of genes or other nucleic acids as drugs, is a powerful new treatment strategy which can be developed to treat GBM. Several treatment modalities are amenable for gene therapy implem...

  2. E2f8 mediates tumor suppression in postnatal liver development

    NARCIS (Netherlands)

    Kent, Lindsey N.; Rakijas, Jessica B.; Pandit, Shusil K.; Westendorp, Bart; Chen, Hui Zi; Huntington, Justin T.; Tang, Xing; Bae, Sooin; Srivastava, Arunima; Senapati, Shantibhusan; Koivisto, Christopher; Martin, Chelsea K.; Cuitino, Maria C.; Perez, Miguel; Clouse, Julian M.; Chokshi, Veda; Shinde, Neelam; Kladney, Raleigh; Sun, Daokun; Perez-Castro, Antonio; Matondo, Ramadhan B.; Nantasanti, Sathidpak; Mokry, Michal; Huang, Kun; Machiraju, Raghu; Fernandez, Soledad; Rosol, Thomas J.; Coppola, Vincenzo; Pohar, Kamal S.; Pipas, James M.; Schmidt, Carl R.; De Bruin, Alain; Leone, Gustavo

    2016-01-01

    E2F-mediated transcriptional repression of cell cycle-dependent gene expression is critical for the control of cellular proliferation, survival, and development. E2F signaling also interacts with transcriptional programs that are downstream of genetic predictors for cancer development, including hep

  3. E2f8 mediates tumor suppression in postnatal liver development

    NARCIS (Netherlands)

    Kent, Lindsey N.; Rakijas, Jessica B.; Pandit, Shusil K.; Westendorp, Bart; Chen, Hui Zi; Huntington, Justin T.; Tang, Xing; Bae, Sooin; Srivastava, Arunima; Senapati, Shantibhusan; Koivisto, Christopher; Martin, Chelsea K.; Cuitino, Maria C.; Perez, Miguel; Clouse, Julian M.; Chokshi, Veda; Shinde, Neelam; Kladney, Raleigh; Sun, Daokun; Perez-Castro, Antonio; Matondo, Ramadhan B.; Nantasanti, Sathidpak; Mokry, Michal; Huang, Kun; Machiraju, Raghu; Fernandez, Soledad; Rosol, Thomas J.; Coppola, Vincenzo; Pohar, Kamal S.; Pipas, James M.; Schmidt, Carl R.; De Bruin, Alain; Leone, Gustavo

    2016-01-01

    E2F-mediated transcriptional repression of cell cycle–dependent gene expression is critical for the control of cellular proliferation, survival, and development. E2F signaling also interacts with transcriptional programs that are downstream of genetic predictors for cancer development, including hep

  4. Silibinin-mediated metabolic reprogramming attenuates pancreatic cancer-induced cachexia and tumor growth.

    Science.gov (United States)

    Shukla, Surendra K; Dasgupta, Aneesha; Mehla, Kamiya; Gunda, Venugopal; Vernucci, Enza; Souchek, Joshua; Goode, Gennifer; King, Ryan; Mishra, Anusha; Rai, Ibha; Nagarajan, Sangeetha; Chaika, Nina V; Yu, Fang; Singh, Pankaj K

    2015-12-01

    Pancreatic ductal adenocarcinoma (PDAC) is the fourth leading cause of cancer-related deaths in the US. Cancer-associated cachexia is present in up to 80% of PDAC patients and is associated with aggressive disease and poor prognosis. In the present studies we evaluated an anti-cancer natural product silibinin for its effectiveness in targeting pancreatic cancer aggressiveness and the cachectic properties of pancreatic cancer cells and tumors. Our results demonstrate that silibinin inhibits pancreatic cancer cell growth in a dose-dependent manner and reduces glycolytic activity of cancer cells. Our LC-MS/MS based metabolomics data demonstrates that silibinin treatment induces global metabolic reprogramming in pancreatic cancer cells. Silibinin treatment diminishes c-MYC expression, a key regulator of cancer metabolism. Furthermore, we observed reduced STAT3 signaling in silibinin-treated cancer cells. Overexpression of constitutively active STAT3 was sufficient to substantially revert the silibinin-induced downregulation of c-MYC and the metabolic phenotype. Our in vivo investigations demonstrate that silibinin reduces tumor growth and proliferation in an orthotopic mouse model of pancreatic cancer and prevents the loss of body weight and muscle. It also improves physical activity including grip strength and latency to fall in tumor-bearing mice. In conclusion, silibinin-induced metabolic reprogramming diminishes cell growth and cachectic properties of pancreatic cancer cells and animal models.

  5. αβ TCR-mediated recognition: relevance to tumor-antigen discovery and cancer immunotherapy.

    Science.gov (United States)

    Reinherz, Ellis L

    2015-04-01

    αβ T lymphocytes sense perturbations in host cellular body components induced by infectious pathogens, oncogenic transformation, or chemical or physical damage. Millions to billions of these lymphocytes are generated through T-lineage development in the thymus, each endowed with a clonally restricted surface T-cell receptor (TCR). An individual TCR has the capacity to recognize a distinct "foreign" peptide among the myriad of antigens that the mammalian host must be capable of detecting. TCRs explicitly distinguish foreign from self-peptides bound to major histocompatibility complex (MHC) molecules. This is a daunting challenge, given that the MHC-linked peptidome consists of thousands of distinct peptides with a relevant nonself target antigen often embedded at low number, among orders of magnitude higher frequency self-peptides. In this Masters of Immunology article, I review how TCR structure and attendant mechanobiology involving nonlinear responses affect sensitivity as well as specificity to meet this requirement. Assessment of human tumor-cell display using state-of-the-art mass spectrometry physical detection methods that quantify epitope copy number can help to provide information about requisite T-cell functional avidity affording protection and/or therapeutic immunity. Future rational CD8 cytotoxic T-cell-based vaccines may follow, targeting virally induced cancers, other nonviral immunogenic tumors, and potentially even nonimmunogenic tumors whose peptide display can be purposely altered by MHC-binding drugs to stimulate immune attack. © 2015 American Association for Cancer Research.

  6. T-cell mediated anti-tumor immunity after photodynamic therapy: Why does it not always work and how can we improve it?

    Science.gov (United States)

    de Freitas, Lucas Freitas; Hamblin, Michael R

    2015-01-01

    Photodynamic therapy (PDT) uses the combination of non-toxic photosensitizers and harmless light to generate reactive oxygen species that destroy tumors by a combination of direct tumor cell killing, vascular shutdown, and activation of the immune system. It has been shown in some animal models that mice that have been cured of cancer by PDT, may exhibit resistance to rechallenge. The cured mice can also possess tumor specific T-cells that recognize defined tumor antigens, destroy tumor cells in vitro, and can be adoptively transferred to protect naïve mice from cancer. However, these beneficial outcomes are the exception rather than the rule. The reasons for this lack of consistency lie in the ability of many tumors to suppress the host immune system and to actively evade immune attack. The presence of an appropriate tumor rejection antigen in the particular tumor cell line is a requisite for T-cell mediated immunity. Regulatory T-cells (CD25+, Foxp3+) are potent inhibitors of anti-tumor immunity, and their removal by low dose cyclophosphamide can potentiate the PDT-induced immune response. Treatments that stimulate dendritic cells (DC) such as CpG oligonucleotide can overcome tumor-induced DC dysfunction and improve PDT outcome. Epigenetic reversal agents can increase tumor expression of MHC class I and also simultaneously increase expression of tumor antigens. A few clinical reports have shown that anti-tumor immunity can be generated by PDT in patients, and it is hoped that these combination approaches may increase tumor cures in patients. PMID:26062987

  7. Adenosine A2A receptors and uric acid mediate protective effects of inosine against TNBS-induced colitis in rats.

    Science.gov (United States)

    Rahimian, Reza; Fakhfouri, Gohar; Daneshmand, Ali; Mohammadi, Hamed; Bahremand, Arash; Rasouli, Mohammad Reza; Mousavizadeh, Kazem; Dehpour, Ahmad Reza

    2010-12-15

    Inflammatory bowel disease comprises chronic recurrent inflammation of gastrointestinal tract. This study was conducted to investigate inosine, a potent immunomodulator, in 2,4,6-trinitrobenzene sulphonic acid (TNBS)-induced chronic model of experimental colitis, and contribution of adenosine A(2A) receptors and the metabolite uric acid as possible underlying mechanisms. Experimental colitis was rendered in rats by a single colonic administration of 10 mg of TNBS. Inosine, potassium oxonate (a hepatic uricase inhibitor), SCH-442416 (a selective adenosine A(2A) receptor antagonist), inosine+potassium oxonate, or inosine+SCH-442416 were given twice daily for 7 successive days. At the end of experiment, macroscopic and histopathologic scores, colonic malondialdehyde (MDA), Tumor Necrosis Factor-alpha (TNF-α) and Interleukin-1beta (IL-1β) levels, and myeloperoxidase (MPO) activity were assessed. Plasma uric acid level was measured throughout the experiment. Both macroscopic and histological features of colonic injury were markedly ameliorated by either inosine, oxonate or inosine+oxonate. Likewise, the elevated amounts of MPO and MDA abated as well as those of TNF-α and IL-1β (Pacid levels were significantly higher in inosine or oxonate groups compared to control. Inosine+oxonate resulted in an even more elvelated uric acid level than each treatment alone (Pacid and adenosine A(2A) receptors contribute to these salutary properties.

  8. Glycan elongation beyond the mucin associated Tn antigen protects tumor cells from immune-mediated killing.

    Directory of Open Access Journals (Sweden)

    Caroline B Madsen

    Full Text Available Membrane bound mucins are up-regulated and aberrantly glycosylated during malignant transformation in many cancer cells. This results in a negatively charged glycoprotein coat which may protect cancer cells from immune surveillance. However, only limited data have so far demonstrated the critical steps in glycan elongation that make aberrantly glycosylated mucins affect the interaction between cancer cells and cytotoxic effector cells of the immune system. Tn (GalNAc-Ser/Thr, STn (NeuAcα2-6GalNAc-Ser/Thr, T (Galβ1-3GalNAc-Ser/Thr, and ST (NeuAcα2-6Galβ1-3GalNAc-Ser/Thr antigens are recognized as cancer associated truncated glycans, and are expressed in many adenocarcinomas, e.g. breast- and pancreatic cancer cells. To investigate the role of the cancer associated glycan truncations in immune-mediated killing we created glyco-engineered breast- and pancreatic cancer cells expressing only the shortest possible mucin-like glycans (Tn and STn. Glyco-engineering was performed by zinc finger nuclease (ZFN knockout (KO of the Core 1 enzyme chaperone COSMC, thereby preventing glycan elongation beyond the initial GalNAc residue in O-linked glycans. We find that COSMC KO in the breast and pancreatic cancer cell lines T47D and Capan-1 increases sensitivity to both NK cell mediated antibody-dependent cellular-cytotoxicity (ADCC and cytotoxic T lymphocyte (CTL-mediated killing. In addition, we investigated the association between total cell surface expression of MUC1/MUC16 and NK or CTL mediated killing, and observed an inverse correlation between MUC16/MUC1 expression and the sensitivity to ADCC and CTL-mediated killing. Together, these data suggest that up-regulation of membrane bound mucins protects cells from immune mediated killing, and that particular glycosylation steps, as demonstrated for glycan elongation beyond Tn and STn, can be important for fine tuning of the immune escape mechanisms in cancer cells.

  9. Tumor necrosis factor-a and its role as a mediator in myocardial infarction:A brief review

    Institute of Scientific and Technical Information of China (English)

    Ming Tian; Yun-Chuan Yuan; Jia-Yi Li; Michael R. Gionfriddo; Rong-Chong Huang

    2015-01-01

    Tumor necrosis factor-a (TNF-a) contributes to myocardial infarction (MI) injury. Polymorphism of TNF-a gene promoter region and secretion and release of TNF-a and its transformation by a series of signaling pathways are all changed at different points of pathophysiological process in MI. Researches also investigated TNF-a antagonists and their potential therapeutic role in the setting of MI and heart failure at both molecular and clinical level. This article briefly reviews TNF-a and its mechanism as a mediator in MI. Copyright © 2015, Chinese Medical Association Production. Production and hosting by Elsevier B.V. on behalf of KeAi Communications Co., Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

  10. The effect of cell-cluster size on intracellular nanoparticle-mediated hyperthermia: is it possible to treat microscopic tumors?

    Science.gov (United States)

    Hedayati, Mohammad; Thomas, Owen; Abubaker-Sharif, Budri; Zhou, Haoming; Cornejo, Christine; Zhang, Yonggang; Wabler, Michele; Mihalic, Jana; Gruettner, Cordula; Westphal, Fritz; Geyh, Alison; Deweese, Theodore l; Ivkov, Robert

    2013-01-01

    Aim To compare the measured surface temperature of variable size ensembles of cells heated by intracellular magnetic fluid hyperthermia with heat diffusion model predictions. Materials & methods Starch-coated Bionized NanoFerrite (Micromod Partikeltechnologie GmbH, Rostock, Germany) iron oxide magnetic nanoparticles were loaded into cultured DU145 prostate cancer cells. Cell pellets of variable size were treated with alternating magnetic fields. The surface temperature of the pellets was measured in situ and the associated cytotoxicity was determined by clonogenic survival assay. Results & conclusion For a given intracellular nanoparticle concentration, a critical minimum number of cells was required for cytotoxic hyperthermia. Above this threshold, cytotoxicity increased with increasing cell number. The measured surface temperatures were consistent with those predicted by a heat diffusion model that ignores intercellular thermal barriers. These results suggest a minimum tumor volume threshold of approximately 1 mm3, below which nanoparticle-mediated heating is unlikely to be effective as the sole cytotoxic agent. PMID:23173694

  11. Inflammatory mediators, tumor necrosis factor-α and interferon-γ, induce EMT in human PTC cell lines.

    Science.gov (United States)

    Lv, Nannan; Gao, Yun; Guan, Haixia; Wu, Dan; Ding, Shuangning; Teng, Weiping; Shan, Zhongyan

    2015-10-01

    Inflammatory mediators, tumor necrosis factor (TNF)-α and interferon (IFN)-γ, promote adverse outcomes in numerous types of cancer; however, their role in papillary thyroid cancer (PTC) remains unclear. The aim of the present study was to investigate the influence of TNF-α and IFN-γ on the migration, invasion and epithelial-mesenchymal transition (EMT) of the three PTC cell lines, TPC-1, BCPAP and K1. The effect of TNF-α and IFN-γ on cell migration and invasion was assessed by wound-healing and Transwell assays. In addition, the mRNA and protein expression levels of the EMT makers, E-cadherin, N-cadherin and vimentin, were analyzed using reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and immunoblot analysis. The wound-healing and Transwell experiments revealed that TNF-α and IFN-γ increased the migratory and invasive behavior of PTC cells (PPTC cells.

  12. Inhibition of KIT RNAi mediated with adenovirus in gastrointestinal stromal tumor xenograft

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    AIM: To investigate a therapeutic method for gastrointestinal stromal tumor (GIST) based on KIT RNA interference (RNAi) with AdMax adenovirus. METHODS: KIT short hairpin RNA (shRNA), whose lateral sides were decorated with restriction endonuclease sequences, was designed. T 4 DNA ligase catalyzed the joint of the KIT shRNA and the green fluorescent protein-containing PDC316-EGFP-U6 to form PDC316EGFP-U6-KIT. Homologous recombination of AdEGFPU6-KIT was performed with the AdMax system. Heterotopically transp...

  13. Targeting MUC1-Mediated Tumor-Stromal Metabolic Interaction in Triple-Negative Breast Cancer

    Science.gov (United States)

    2016-11-01

    of law, no person shall be subject to any penalty for failing to comply with a collection of information if it does not display a currently valid OMB...15 11. Appendices…………………………………………………………. 15 INTRODUCTION Breast cancer, the second leading cause of cancer deaths in...the leading cause of cancer related deaths , this process relies on cooperation between the tumor cells and their surrounding stromal, establishing a

  14. Cisplatin hypersensitivity of testicular germ cell tumors is determined by high constitutive Noxa levels mediated by Oct-4.

    Science.gov (United States)

    Gutekunst, Matthias; Mueller, Thomas; Weilbacher, Andrea; Dengler, Michael A; Bedke, Jens; Kruck, Stephan; Oren, Moshe; Aulitzky, Walter E; van der Kuip, Heiko

    2013-03-01

    Testicular germ cell tumors (TGCT) are considered a paradigm of chemosensitive tumors. Embryonal carcinoma cells represent the pluripotent entity of TGCTs and are characterized by expression of Oct-4, a key regulator of pluripotency and a determinant of their inherent hypersensitivity to cisplatin. However, the mechanisms underlying this Oct-4-mediated sensitivity are poorly understood. We previously showed that p53 is a major player in cisplatin hypersensitivity and therefore investigated whether Oct-4 may directly affect p53 activity. Despite a significant decrease in sensitivity, depletion of Oct-4 neither did alter cisplatin-induced transactivation of p53 target genes nor its subcellular localization. These data indicate that, rather than directly modulating p53 activity, Oct-4 provides a cellular context that augments the proapoptotic activity of p53. As mitochondrial priming by the Bcl-2 family is a known determinant of chemosensitivity, we compared the constitutive levels of these proteins in Oct-4-positive and -depleted cells. We identified Noxa as the only Bcl-2 family protein to be highly correlated with Oct-4 status and cisplatin sensitivity. Compared with differentiated cells, constitutive Noxa levels were significantly higher in Oct-4-positive cell lines and cancer patient samples. Furthermore, RNA interference-mediated knockdown of Oct-4 resulted in reduced Noxa transcript, in an almost complete loss of constitutive Noxa protein and decreased cisplatin hypersensitivity to a similar extent as did Noxa depletion. In conclusion, our study indicates that Noxa is a central determinant of hypersensitivity to cisplatin. Oct-4-dependent high constitutive levels of this BH3-only protein prime embryonal carcinoma cells to undergo rapid and massive apoptosis in response to p53 activation.

  15. Activation of inflammasomes by tumor cell death mediated by gold nanoshells.

    Science.gov (United States)

    Nguyen, Hai T; Tran, Kenny K; Sun, Bingbing; Shen, Hong

    2012-03-01

    Gold nanoshell-enabled photothermal therapy (NEPTT) utilizes the efficient thermal conversion of near infrared (NIR) light for the ablation of cancer cells. Cancer therapies that combine cell killing with the induction of a strong immune response against the dying tumor cells have been shown to increase therapeutic efficacy in the clearance and regression of cancers. In this study, we assessed the ability of dying cells generated by in vitro NEPTT to activate inflammasome complexes. We quantified levels of major danger-associated molecular patterns (DAMPs), including adenosine triphosphate (ATP), adenosine diphosphate (ADP), and uric acid, released from tumor cells treated by NEPTT. The amount of DAMPs released was dependent on the dose of nanoshells internalized by cells. However, under all the employed conditions, the levels of generated DAMPs were insufficient to activate inflammasome complexes and to induce the production of pro-inflammatory cytokines (i.e. IL-1β). The results from this study provide insights into the development of nanoplasmonics for combining both photothermal therapy and immunotherapy to eradicate cancers.

  16. Eupatilin protects against tumor necrosis factor-α-mediated inflammation inhuman umbilical vein endothelial cells.

    Science.gov (United States)

    Yu, Kai; Li, Xi-Ming; Xu, Xiao-Lei; Zhang, Ru-Yan; Cong, Hong-Liang

    2015-01-01

    Inflammatory responses in the blood vessel play a pivotal role in the pathogenesis of atherosclerosis. Eupatilin, a flavone derived from Artemisia princepsPampanini, has various pharmacological activities, including antioxidant, anti-tumor, and anti-inflammatory capacities. However, there has been no research examining the function of eupatilin on vascular inflammation. Therefore, the aim of this study was to investigate the effects of eupatilin on tumor necrosis factor (TNF)-α-induced human umbilical vein endothelial cells (HUVECs) activation and the underlying molecular mechanisms. Our findings showed that eupatilin reduced U937 cells adhesion to TNF-α-stimulated HUVECs and attenuated TNF-α-induced the expression of vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) in HUVECs, as well as the production of intracellular reactive oxygen species (ROS). Moreover, eupatilininhibits TNF-α-induced phosphorylation of NF-kB p65 and MAPKs in HUVECs. Taken together, the results of the present study suggest that eupatilin inhibited inflammatory reaction through suppressing the ROS/MAPK-NF-ĸB pathway in HUVECs. Thus, eupatilin is proposed as an effective new anti-inflammatory agent to suppress vascular inflammation, and further prevent atherosclerosis.

  17. The tumor suppressor, parafibromin, mediates histone H3 K9 methylation for cyclin D1 repression.

    Science.gov (United States)

    Yang, Yong-Jin; Han, Jeung-Whan; Youn, Hong-Duk; Cho, Eun-Jung

    2010-01-01

    Parafibromin, a component of the RNA polymerase II-associated PAF1 complex, is a tumor suppressor linked to hyperparathyroidism-jaw tumor syndrome and sporadic parathyroid carcinoma. Parafibromin induces cell cycle arrest by repressing cyclin D1 via an unknown mechanism. Here, we show that parafibromin interacts with the histone methyltransferase, SUV39H1, and functions as a transcriptional repressor. The central region (128-227 amino acids) of parafibromin is important for both the interaction with SUV39H1 and transcriptional repression. Parafibromin associated with the promoter and coding regions of cyclin D1 and was required for the recruitment of SUV39H1 and the induction of H3 K9 methylation but not H3 K4 methylation. RNA interference analysis showed that SUV39H1 was critical for cyclin D1 repression. These data suggest that parafibromin plays an unexpected role as a repressor in addition to its widely known activity associated with transcriptional activation. Parafibromin as a part of the PAF1 complex might downregulate cyclin D1 expression by integrating repressive H3 K9 methylation during transcription.

  18. Endostar attenuates melanoma tumor growth via its interruption of b-FGF mediated angiogenesis.

    Science.gov (United States)

    Xiao, Lijia; Yang, ShuCai; Hao, Jianhua; Yuan, Xue; Luo, Wei; Jiang, Liping; Hu, Yang; Fu, Zhongping; Zhang, Yun; Zou, Chang

    2015-04-01

    To develop optimal therapeutics is one of the hotspots in both clinical and basic melanoma studies. Previous studies indicate that fibroblast growth factors (b-FGF/FGF-2), an angiogenesis inducer beyond VEGF, might be a potential drug target in melanoma. As a novel anti-angiogenesis peptide drug, Endostar has shown promising therapeutic efficacy in non-small cell lung cancer. However, the effect of Endostar on b-FGF-induced angiogenesis in melanoma is unraveled. To this end, both in vivo and in vitro experiments were conducted and it was found that treatment of Endostar could inhibit tumor growth, which was accompanied by decreased micro-vessel density and serum b-FGF levels in a mouse melanoma model. In addition, treatment with Endostar in blood vessel endothelial cells could reduce their proliferation, cell migration and tube formation capacity in a dosage-dependent manner. Moreover, treatment of Endostar could also attenuate b-FGF-activated phosphorylation of p38 and ERK1/2 in HUVECs. These findings indicate that Endostar might exert its anti-tumor effect via suppressing b-FGF-induced angiogenesis and b-FGF-activated MAPK signaling pathway, suggesting that Endostar might be a potential choice for clinical melanoma treatment.

  19. Lentivirus-Mediated Oncogene Introduction into Mammary Cells In Vivo Induces Tumors

    Directory of Open Access Journals (Sweden)

    Stefan K. Siwko

    2008-07-01

    Full Text Available We recently reported the introduction of oncogene-expressing avian retroviruses into somatic mammary cells in mice susceptible to infection by transgenic expression of tva, encoding the receptor for subgroup A avian leukosis-sarcoma virus (ALSV. Because ALSV-based vectors poorly infect nondividing cells, they are inadequate for studying carcinogenesis initiated from nonproliferative cells (e.g., stem cells. Lentivirus pseudotyped with the envelope protein of ALSV infects nondividing TVA-producing cells in culture but has not previously been tested for introducing genes in vivo. Here, we demonstrate that these vectors infected mammary cells in vivo when injected into the mammary ductal lumen of mice expressing tva under the control of the keratin 19 promoter. Furthermore, intraductal injection of this lentiviral vector carrying the polyoma middle T antigen gene induced atypical ductal hyperplasia and ductal carcinoma in situ-like premalignant lesions in 30 days and palpable invasive tumors at a median latency of 3.3 months. Induced tumors were a mixed epithelial/myoepithelial histologic diagnosis, occasionally displayed squamous metaplasia, and were estrogen receptor-negative. This work demonstrates the first use of a lentiviral vector to introduce oncogenes for modeling cancer in mice, and this vector system may be especially suitable for introducing genetic alterations into quiescent cells in vivo.

  20. Type I collagen aging impairs discoidin domain receptor 2-mediated tumor cell growth suppression.

    Science.gov (United States)

    Saby, Charles; Buache, Emilie; Brassart-Pasco, Sylvie; El Btaouri, Hassan; Courageot, Marie-Pierre; Van Gulick, Laurence; Garnotel, Roselyne; Jeannesson, Pierre; Morjani, Hamid

    2016-05-03

    Tumor cells are confronted to a type I collagen rich environment which regulates cell proliferation and invasion. Biological aging has been associated with structural changes of type I collagen. Here, we address the effect of collagen aging on cell proliferation in a three-dimensional context (3D).We provide evidence for an inhibitory effect of adult collagen, but not of the old one, on proliferation of human fibrosarcoma HT-1080 cells. This effect involves both the activation of the tyrosine kinase Discoidin Domain Receptor 2 (DDR2) and the tyrosine phosphatase SHP-2. DDR2 and SHP-2 were less activated in old collagen. DDR2 inhibition decreased SHP-2 phosphorylation in adult collagen and increased cell proliferation to a level similar to that observed in old collagen.In the presence of old collagen, a high level of JAK2 and ERK1/2 phosphorylation was observed while expression of the cell cycle negative regulator p21CIP1 was decreased. Inhibition of DDR2 kinase function also led to an increase in ERK1/2 phosphorylation and a decrease in p21CIP1 expression. Similar signaling profile was observed when DDR2 was inhibited in adult collagen. Altogether, these data suggest that biological collagen aging could increase tumor cell proliferation by reducingthe activation of the key matrix sensor DDR2.

  1. N-linked glycans within the A2 domain of von Willebrand factor modulate macrophage-mediated clearance.

    Science.gov (United States)

    Chion, Alain; O'Sullivan, Jamie M; Drakeford, Clive; Bergsson, Gudmundur; Dalton, Niall; Aguila, Sonia; Ward, Soracha; Fallon, Padraic G; Brophy, Teresa M; Preston, Roger J S; Brady, Lauren; Sheils, Orla; Laffan, Michael; McKinnon, Thomas A J; O'Donnell, James S

    2016-10-13

    Enhanced von Willebrand factor (VWF) clearance is important in the etiology of von Willebrand disease. However, the molecular mechanisms underlying VWF clearance remain poorly understood. In this study, we investigated the role of VWF domains and specific glycan moieties in regulating in vivo clearance. Our findings demonstrate that the A1 domain of VWF contains a receptor-recognition site that plays a key role in regulating the interaction of VWF with macrophages. In A1-A2-A3 and full-length VWF, this macrophage-binding site is cryptic but becomes exposed following exposure to shear or ristocetin. Previous studies have demonstrated that the N-linked glycans within the A2 domain play an important role in modulating susceptibility to ADAMTS13 proteolysis. We further demonstrate that these glycans presented at N1515 and N1574 also play a critical role in protecting VWF against macrophage binding and clearance. Indeed, loss of the N-glycan at N1515 resulted in markedly enhanced VWF clearance that was significantly faster than that observed with any previously described VWF mutations. In addition, A1-A2-A3 fragments containing the N1515Q or N1574Q substitutions also demonstrated significantly enhanced clearance. Importantly, clodronate-induced macrophage depletion significantly attenuated the increased clearance observed with N1515Q and N1574Q in both full-length VWF and A1-A2-A3. Finally, we further demonstrate that loss of these N-linked glycans does not enhance clearance in VWF in the presence of a structurally constrained A2 domain. Collectively, these novel findings support the hypothesis that conformation of the VWF A domains plays a critical role in modulating macrophage-mediated clearance of VWF in vivo.

  2. Marked detergents effects on safranine T-mediated photo-induced electron transfer in cytochrome P-450 1A2.

    Science.gov (United States)

    Nakano, R; Konami, H; Sato, H; Ito, O; Shimizu, T

    1995-10-25

    Cytochrome P-450 accepts electrons from electron transfer proteins to facilitate monooxidation reactions. It is suggested that basic amino acids such as Lys and Arg on the P-450 molecular surface interact with acidic amino acids such as Glu and Asp of the electron transfer protein. Safranine T is a basic compound which mediates electron transfer with illumination. It was found with flash photolysis that an electron from photo-reduced safranine T quickly reaches the heme iron of cytochrome P-450 1A2 (P-450 1A2). The photo-induced reduction kinetics of P-450 1A2 were analyzed by the Runge-Kutta method on the second order assumption. The electron-transfer rate constant from safranine T to P-450 1A2 was 2.1 x 10(6) M-1s-1. The rate constant was remarkably increased up to 3.1 x 10(8) M-1s-1 by adding cholic acid, while that was drastically reduced down to 3.5 x 10(4) M-1s-1 by adding Emulgen 913. The electron-transfer rate of a His163-Glu mutant, which has a 40 mV lower redox potential than that of the wild type, was the same as that of the wild type in the absence of the detergents, although the reduced fraction of the mutant was 30% lower than that of the wild type. The electron-transfer rate of the mutant also changed significantly by adding the detergents in the same way as the wild type. Based on these results, together with optical absorbance and fluorescence data, we discuss the inter- and intramolecular electron-transfer mechanism of P-450 1A2.

  3. PI3-kinase γ promotes Rap1a-mediated activation of myeloid cell integrin α4β1, leading to tumor inflammation and growth.

    Directory of Open Access Journals (Sweden)

    Michael C Schmid

    Full Text Available Tumor inflammation, the recruitment of myeloid lineage cells into the tumor microenvironment, promotes angiogenesis, immunosuppression and metastasis. CD11b+Gr1lo monocytic lineage cells and CD11b+Gr1hi granulocytic lineage cells are recruited from the circulation by tumor-derived chemoattractants, which stimulate PI3-kinase γ (PI3Kγ-mediated integrin α4 activation and extravasation. We show here that PI3Kγ activates PLCγ, leading to RasGrp/CalDAG-GEF-I&II mediated, Rap1a-dependent activation of integrin α4β1, extravasation of monocytes and granulocytes, and inflammation-associated tumor progression. Genetic depletion of PLCγ, CalDAG-GEFI or II, Rap1a, or the Rap1 effector RIAM was sufficient to prevent integrin α4 activation by chemoattractants or activated PI3Kγ (p110γCAAX, while activated Rap (RapV12 promoted constitutive integrin activation and cell adhesion that could only be blocked by inhibition of RIAM or integrin α4β1. Similar to blockade of PI3Kγ or integrin α4β1, blockade of Rap1a suppressed both the recruitment of monocytes and granulocytes to tumors and tumor progression. These results demonstrate critical roles for a PI3Kγ-Rap1a-dependent pathway in integrin activation during tumor inflammation and suggest novel avenues for cancer therapy.

  4. cAMP/CREB-regulated LINC00473 marks LKB1-inactivated lung cancer and mediates tumor growth.

    Science.gov (United States)

    Chen, Zirong; Li, Jian-Liang; Lin, Shuibin; Cao, Chunxia; Gimbrone, Nicholas T; Yang, Rongqiang; Fu, Dongtao A; Carper, Miranda B; Haura, Eric B; Schabath, Matthew B; Lu, Jianrong; Amelio, Antonio L; Cress, W Douglas; Kaye, Frederic J; Wu, Lizi

    2016-06-01

    The LKB1 tumor suppressor gene is frequently mutated and inactivated in non-small cell lung cancer (NSCLC). Loss of LKB1 promotes cancer progression and influences therapeutic responses in preclinical studies; however, specific targeted therapies for lung cancer with LKB1 inactivation are currently unavailable. Here, we have identified a long noncoding RNA (lncRNA) signature that is associated with the loss of LKB1 function. We discovered that LINC00473 is consistently the most highly induced gene in LKB1-inactivated human primary NSCLC samples and derived cell lines. Elevated LINC00473 expression correlated with poor prognosis, and sustained LINC00473 expression was required for the growth and survival of LKB1-inactivated NSCLC cells. Mechanistically, LINC00473 was induced by LKB1 inactivation and subsequent cyclic AMP-responsive element-binding protein (CREB)/CREB-regulated transcription coactivator (CRTC) activation. We determined that LINC00473 is a nuclear lncRNA and interacts with NONO, a component of the cAMP signaling pathway, thereby facilitating CRTC/CREB-mediated transcription. Collectively, our study demonstrates that LINC00473 expression potentially serves as a robust biomarker for tumor LKB1 functional status that can be integrated into clinical trials for patient selection and treatment evaluation, and implicates LINC00473 as a therapeutic target for LKB1-inactivated NSCLC.

  5. Albumin-Mediated Biomineralization of Paramagnetic NIR Ag2S QDs for Tiny Tumor Bimodal Targeted Imaging in Vivo.

    Science.gov (United States)

    Zhang, Jing; Hao, Guangyu; Yao, Chenfei; Yu, Jiani; Wang, Jun; Yang, Weitao; Hu, Chunhong; Zhang, Bingbo

    2016-07-06

    Bimodal imaging has captured increasing interests due to its complementary characteristics of two kinds of imaging modalities. Among the various dual-modal imaging techniques, MR/fluorescence imaging has been widely studied owing to its high 3D resolution and sensitivity. There is, however, still a strong demand to construct biocompatible MR/fluorescence contrast agents with near-infrared (NIR) fluorescent emissions and high relaxivities. In this study, BSA-DTPA(Gd) derived from bovine serum albumin (BSA) as a novel kind of biotemplate is employed for biomineralization of paramagnetic NIR Ag2S quantum dots (denoted as Ag2S@BSA-DTPA(Gd) pQDs). This synthetic strategy is found to be bioinspired, environmentally benign, and straightforward. The obtained Ag2S@BSA-DTPA(Gd) pQDs have fine sizes (ca. 6 nm) and good colloidal stability. They exhibit unabated NIR fluorescent emission (ca. 790 nm) as well as high longitudinal relaxivity (r1 = 12.6 mM(-1) s(-1)) compared to that of commercial Magnevist (r1 = 3.13 mM(-1) s(-1)). In vivo tumor-bearing MR and fluorescence imaging both demonstrate that Ag2S@BSA-DTPA(Gd) pQDs have pronounced tiny tumor targeting capability. In vitro and in vivo toxicity study show Ag2S@BSA-DTPA(Gd) pQDs are biocompatible. Also, biodistribution analysis indicates they can be cleared from body mainly via liver metabolism. This protein-mediated biomineralized Ag2S@BSA-DTPA(Gd) pQDs presents great potential as a novel bimodal imaging contrast agent for tiny tumor diagnosis.

  6. Acquired Tumor Cell Radiation Resistance at the Treatment Site Is Mediated Through Radiation-Orchestrated Intercellular Communication

    Energy Technology Data Exchange (ETDEWEB)

    Aravindan, Natarajan, E-mail: naravind@ouhsc.edu [Department of Radiation Oncology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma (United States); Aravindan, Sheeja; Pandian, Vijayabaskar; Khan, Faizan H.; Ramraj, Satish Kumar; Natt, Praveen [Department of Radiation Oncology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma (United States); Natarajan, Mohan [Department of Pathology, The University of Texas Health Science Center at San Antonio, San Antonio, Texas (United States)

    2014-03-01

    Purpose: Radiation resistance induced in cancer cells that survive after radiation therapy (RT) could be associated with increased radiation protection, limiting the therapeutic benefit of radiation. Herein we investigated the sequential mechanistic molecular orchestration involved in radiation-induced radiation protection in tumor cells. Results: Radiation, both in the low-dose irradiation (LDIR) range (10, 50, or 100 cGy) or at a higher, challenge dose IR (CDIR), 4 Gy, induced dose-dependent and sustained NFκB-DNA binding activity. However, a robust and consistent increase was seen in CDIR-induced NFκB activity, decreased DNA fragmentation, apoptosis, and cytotoxicity and attenuation of CDIR-inhibited clonal expansion when the cells were primed with LDIR prior to challenge dose. Furthermore, NFκB manipulation studies with small interfering RNA (siRNA) silencing or p50/p65 overexpression unveiled the influence of LDIR-activated NFκB in regulating CDIR-induced DNA fragmentation and apoptosis. LDIR significantly increased the transactivation/translation of the radiation-responsive factors tumor necrosis factor-α (TNF-α), interleukin-1α (IL-1α), cMYC, and SOD2. Coculture experiments exhibit LDIR-influenced radiation protection and increases in cellular expression, secretion, and activation of radiation-responsive molecules in bystander cells. Individual gene-silencing approach with siRNAs coupled with coculture studies showed the influence of LDIR-modulated TNF-α, IL-1α, cMYC, and SOD2 in induced radiation protection in bystander cells. NFκB inhibition/overexpression studies coupled with coculture experiments demonstrated that TNF-α, IL-1α, cMYC, and SOD2 are selectively regulated by LDIR-induced NFκB. Conclusions: Together, these data strongly suggest that scattered LDIR-induced NFκB-dependent TNF-α, IL-1α, cMYC, and SOD2 mediate radiation protection to the subsequent challenge dose in tumor cells.

  7. Nonsense-Mediated mRNA Decay Impacts MSI-Driven Carcinogenesis and Anti-Tumor Immunity in Colorectal Cancers

    Science.gov (United States)

    El-Bchiri, Jamila; Guilloux, Agathe; Dartigues, Peggy; Loire, Etienne; Mercier, Dominique; Buhard, Olivier; Sobhani, Iradj; de la Grange, Pierre; Auboeuf, Didier; Praz, Françoise; Fléjou, Jean-François; Duval, Alex

    2008-01-01

    Nonsense-mediated mRNA Decay (NMD) degrades mutant mRNAs containing premature termination codon (PTC-mRNAs). Here we evaluate the consequence of NMD activity in colorectal cancers (CRCs) showing microsatellite instability (MSI) whose progression is associated with the accumulation of PTC-mRNAs encoding immunogenic proteins due to frameshift mutations in coding repeat sequences. Inhibition of UPF1, one of the major NMD factors, was achieved by siRNA in the HCT116 MSI CRC cell line and the resulting changes in gene expression were studied using expression microarrays. The impact of NMD activity was also investigated in primary MSI CRCs by quantifying the expression of several mRNAs relative to their mutational status and to endogenous UPF1 and UPF2 expression. Host immunity developed against MSI cancer cells was appreciated by quantifying the number of CD3ε-positive tumor-infiltrating lymphocytes (TILs). UPF1 silencing led to the up-regulation of 1251 genes in HCT116, among which a proportion of them (i.e. 38%) significantly higher than expected by chance contained a coding microsatellite (P<2×10−16). In MSI primary CRCs, UPF1 was significantly over-expressed compared to normal adjacent mucosa (P<0.002). Our data provided evidence for differential decay of PTC-mRNAs compared to wild-type that was positively correlated to UPF1 endogenous expression level (P = 0.02). A negative effect of UPF1 and UPF2 expression on the host's anti-tumor response was observed (P<0.01). Overall, our results show that NMD deeply influences MSI-driven tumorigenesis at the molecular level and indicate a functional negative impact of this system on anti-tumor immunity whose intensity has been recurrently shown to be an independent factor of favorable outcome in CRCs. PMID:18612427

  8. Gene Targets in Prostate Tumor Cells that Mediate Aberrant Growth and Invasiveness

    Science.gov (United States)

    2005-02-01

    named EIAF ( Higashino et al. 1993). Finally, PEA3/EI AF was found to be the fourth Ets factor involved in chromosomal fusions with EWS (Kaneko et al. 1996...in transcriptional repression mediated by the t(8;21), t(16;21), t(12;21), and inv(16) fusion proteins. Curr Opin Hematol 8:197-200 Higashino F...Yoshida K, Handa M, Toyoda Y, Nishihira H, Tanaka Y, Sasaki Y, Ishida S, Higashino F, Fuj inaga K (1996) Fusion of an ETS-family gene, EIAF, to EWS by t

  9. Hyaluronan synthase 3 mediated oncogenic action through forming inter-regulation loop with tumor necrosis factor alpha in oral cancer

    Science.gov (United States)

    Kuo, Yi-Zih; Fang, Wei-Yu; Huang, Cheng-Chih; Tsai, Sen-Tien; Wang, Yi-Ching; Yang, Chih-Li; Wu, Li-Wha

    2017-01-01

    Hyaluronan (HA) is a major extracellular matrix component. However, its role and mediation in oral cancer remains elusive. Hyaluronan synthase 3 (HAS3), involved in pro-inflammatory short chain HA synthesis, was the predominant synthase in oral cancer cells and tissues. HAS3 overexpression significantly increased oral cancer cell migration, invasion and xenograft tumorigenesis accompanied with the increased expression of tumor necrosis factor alpha (TNF-α) and monocyte chemoattractant protein 1 (MCP-1). Conversely, HAS3 depletion abrogated HAS3-mediated stimulation. HAS3 induced oncogenic actions partly through activating EGFR-SRC signaling. HAS3-derived HA release into extracellular milieu enhanced transendothelial monocyte migration and MCP-1 expression, which was attenuated by anti-HAS3 antibodies or a HAS inhibitor, 4-Methylumbelliferone (4-MU). The NF-κB-binding site III at -1692 to -1682 bp upstream from the transcript 1 start site in HAS3 proximal promoter was the most responsive to TNF-α-stimulated transcription. ChIP-qPCR analysis confirmed the highest NF-κB-p65 enrichment on site III. Increased HAS3 mRNA expression was negatively correlated with the overall survival of oral cancer patients. A concomitant increase of TNF-α, a stimulus for HAS3 expression, with HAS3 expression was not only associated with lymph node metastasis but also negated clinical outcome. Together, HAS3 and TNF-α formed an inter-regulation loop to enhance tumorigenesis in oral cancer. PMID:28107185

  10. Nortriptyline induces mitochondria and death receptor-mediated apoptosis in bladder cancer cells and inhibits bladder tumor growth in vivo.

    Science.gov (United States)

    Yuan, Sheau-Yun; Cheng, Chen-Li; Ho, Hao-Chung; Wang, Shian-Shiang; Chiu, Kun-Yuan; Su, Chung-Kuang; Ou, Yen-Chuan; Lin, Chi-Chen

    2015-08-15

    Nortriptyline (NTP), an antidepressant, has antitumor effects on some human cancer cells, but its effect on human bladder cancer cells is not known. In this study, we used a cell viability assay to demonstrate that NTP is cytotoxic to human TCCSUP and mouse MBT-2 bladder cancer cells in a concentration and time-dependent manner. We also performed cell cycle analysis, annexin V and mitochondrial membrane potential assays, and Western blot analysis to show that NTP inhibits cell growth in these cells by inducing both mitochondria-mediated and death receptor-mediated apoptosis. Specifically, NTP increases the expression of Fas, FasL, FADD, Bax, Bak, and cleaved forms of caspase-3, caspase-8, caspase-9, and poly(ADP-ribose) polymerase. In addition, NTP decreases the expression of Bcl-2, Bcl-xL, BH3 interacting domain death agonist, X-linked inhibitor of apoptosis protein, and survivin. Furthermore, NTP-induced apoptosis is associated with reactive oxygen species (ROS) production, which can be reduced by antioxidants, such as N-acetyl-L-cysteine. Finally, we showed that NTP suppresses tumor growth in mice inoculated with MBT-2 cells. Collectively, our results suggest that NTP induces both intrinsic and extrinsic apoptosis in human and mouse bladder cancer cells and that it may be a clinically useful chemotherapeutic agent for bladder cancer in humans. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Mediatization

    DEFF Research Database (Denmark)

    Hjarvard, Stig

    2017-01-01

    Mediatization research shares media effects studies' ambition of answering the difficult questions with regard to whether and how media matter and influence contemporary culture and society. The two approaches nevertheless differ fundamentally in that mediatization research seeks answers...... to these general questions by distinguishing between two concepts: mediation and mediatization. The media effects tradition generally considers the effects of the media to be a result of individuals being exposed to media content, i.e. effects are seen as an outcome of mediated communication. Mediatization...... research is concerned with long-term structural changes involving media, culture, and society, i.e. the influences of the media are understood in relation to how media are implicated in social and cultural changes and how these processes come to create new conditions for human communication and interaction...

  12. Boron-Containing Compounds for Liposome-Mediated Tumor Localization and Application to Neutron Capture Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Hawthorne, M. Frederick [Univ. of California, Los Angeles, CA (United States)

    2005-04-07

    Medical application of boron neutron capture therapy (BNCT) has been significantly hindered by the slow development of boron drug-targeting methodologies for the selective delivery of high boron concentration sto malignant cells. We have successfully sought to fill this need by creating liposomes suitable as in vivo boron delivery vehicles for BNCT. Delivery of therapeutic quantities of boron to tumors in murine models has been achieved with small unilamellar boron-rich liposomes. Subsequently, attempts have been made to improve delivery efficiency of liposomes encapsulating boron-containing water-soluble species into their hollow core by incorporating lipophilic boron compounds as addenda to the liposome bilayer, incorporating boron compounds as structural components of the bilayer (which however, poses the risk of sacrificing some stability), and combinations thereof. Regardless of the method, approximately 90% of the total liposome mass remains therapeutically inactive and comprised of the vehicle's construction materials, while less than 5% is boron for neutron targeting. Following this laboratory's intensive study, the observed tumor specificity of certain liposomes has been attributed to their diminutive size of these liposomes (30-150 nm), which enables these small vesicles to pass through the porous, immature vasculature of rapidly growing tumor tissue. We surmised that any amphiphilic nanoparticle of suitable size could possess some tumor selectivity. Consequently, the discovery of a very boron-rich nanoparticle delivery agent with biodistribution performance similar to unilamellar liposomes became one of our goals. Closomers, a new class of polyhedral borane derivatives, attracted us as an alternative BNCT drug-delivery system. We specifically envisioned dodeca (nido-carboranyl)-substituted closomers as possibly having a great potential role in BNCT drug delivery. They could function as extraordinarily boron-rich BNCT drugs since they are

  13. Boron-Containing Compounds for Liposome-Mediated Tumor Localization and Application to Neutron Capture Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Hawthorne, M. Frederick [Univ. of California, Los Angeles, CA (United States)

    2005-04-07

    Medical application of boron neutron capture therapy (BNCT) has been significantly hindered by the slow development of boron drug-targeting methodologies for the selective delivery of high boron concentration sto malignant cells. We have successfully sought to fill this need by creating liposomes suitable as in vivo boron delivery vehicles for BNCT. Delivery of therapeutic quantities of boron to tumors in murine models has been achieved with small unilamellar boron-rich liposomes. Subsequently, attempts have been made to improve delivery efficiency of liposomes encapsulating boron-containing water-soluble species into their hollow core by incorporating lipophilic boron compounds as addenda to the liposome bilayer, incorporating boron compounds as structural components of the bilayer (which however, poses the risk of sacrificing some stability), and combinations thereof. Regardless of the method, approximately 90% of the total liposome mass remains therapeutically inactive and comprised of the vehicle's construction materials, while less than 5% is boron for neutron targeting. Following this laboratory's intensive study, the observed tumor specificity of certain liposomes has been attributed to their diminutive size of these liposomes (30-150 nm), which enables these small vesicles to pass through the porous, immature vasculature of rapidly growing tumor tissue. We surmised that any amphiphilic nanoparticle of suitable size could possess some tumor selectivity. Consequently, the discovery of a very boron-rich nanoparticle delivery agent with biodistribution performance similar to unilamellar liposomes became one of our goals. Closomers, a new class of polyhedral borane derivatives, attracted us as an alternative BNCT drug-delivery system. We specifically envisioned dodeca (nido-carboranyl)-substituted closomers as possibly having a great potential role in BNCT drug delivery. They could function as extraordinarily boron-rich BNCT drugs since they are

  14. Downregulation of protein kinase CK2 activity facilitates tumor necrosis factor-α-mediated chondrocyte death through apoptosis and autophagy.

    Directory of Open Access Journals (Sweden)

    Sung Won Lee

    Full Text Available Despite the numerous studies of protein kinase CK2, little progress has been made in understanding its function in chondrocyte death. Our previous study first demonstrated that CK2 is involved in apoptosis of rat articular chondrocytes. Recent studies have suggested that CK2 downregulation is associated with aging. Thus examining the involvement of CK2 downregulation in chondrocyte death is an urgently required task. We undertook this study to examine whether CK2 downregulation modulates chondrocyte death. We first measured CK2 activity in articular chondrocytes of 6-, 21- and 30-month-old rats. Noticeably, CK2 activity was downregulated in chondrocytes with advancing age. To build an in vitro experimental system for simulating tumor necrosis factor (TNF-α-induced cell death in aged chondrocytes with decreased CK2 activity, chondrocytes were co-treated with CK2 inhibitors and TNF-α. Viability assay demonstrated that CK2 inhibitors facilitated TNF-α-mediated chondrocyte death. Pulsed-field gel electrophoresis, nuclear staining, flow cytometry, TUNEL staining, confocal microscopy, western blot and transmission electron microscopy were conducted to assess cell death modes. The results of multiple assays showed that this cell death was mediated by apoptosis. Importantly, autophagy was also involved in this process, as supported by the appearance of a punctuate LC3 pattern and autophagic vacuoles. The inhibition of autophagy by silencing of autophage-related genes 5 and 7 as well as by 3-methyladenine treatment protected chondrocytes against cell death and caspase activation, indicating that autophagy led to the induction of apoptosis. Autophagic cells were observed in cartilage obtained from osteoarthritis (OA model rats and human OA patients. Our findings indicate that CK2 down regulation facilitates TNF-α-mediated chondrocyte death through apoptosis and autophagy. It should be clarified in the future if autophagy observed is a consequence

  15. GRP78 as a regulator of liver steatosis and cancer progression mediated by loss of the tumor suppressor PTEN.

    Science.gov (United States)

    Chen, W-T; Zhu, G; Pfaffenbach, K; Kanel, G; Stiles, B; Lee, A S

    2014-10-16

    Glucose-regulated protein 78 (GRP78), a molecular chaperone widely elevated in human cancers, is critical for endoplasmic reticulum (ER) protein folding, stress signaling and PI3K/AKT activation. Genetic knockout models of GRP78 revealed that GRP78 maintains homeostasis of metabolic organs, including liver, pancreas and adipose tissues. Hepatocellular carcinoma (HCC) and cholangiocarcinoma (CC) are the most common liver cancers. There is a lack of effective therapeutics for HCC and CC, highlighting the need to further understand liver tumorigenic mechanisms. PTEN (phosphatase and tenson homolog deleted on chromosome 10), a tumor suppressor that antagonizes the PI3K/AKT pathway, is inactivated in a wide range of tumors, including 40-50% of human liver cancers. To elucidate the role of GRP78 in liver cancer, we created a mouse model with biallelic liver-specific deletion of Pten and Grp78 mediated by Albumin-Cre-recombinase (cP(f/f)78(f/f)). Interestingly, in contrast to PTEN, deletion of GRP78 was progressive but incomplete. At 3 months, cP(f/f)78(f/f) livers showed hepatomegaly, activation of lipogenic genes, exacerbated steatosis and liver injury, implying that GRP78 protects the liver against PTEN-null-mediated pathogenesis. Furthermore, in response to liver injury, we observed increased proliferation and expansion of bile duct and liver progenitor cells in cP(f/f)78(f/f) livers. Strikingly, bile duct cells in cP(f/f)78(f/f) livers maintained wild-type (WT) GRP78 level, whereas adjacent areas showed GRP78 reduction. Analysis of signaling pathways revealed selective JNK activation, β-catenin downregulation, along with PDGFRα upregulation, which was unique to cP(f/f)78(f/f) livers at 6 months. Development of both HCC and CC was accelerated and was evident in cP(f/f)78(f/f) livers at 8-9 months, coinciding with intense GRP78 expression in the cancer lesions, and GRP78 expression in adjacent normal areas reverted back to the WT level. In contrast, c78(f/f) livers

  16. Induction of NKG2D ligands and increased sensitivity of tumor cells to NK cell-mediated cytotoxicity by hematoporphyrin-based photodynamic therapy.

    Science.gov (United States)

    Park, Min-Ju; Bae, Jae-Ho; Chung, Joo Seop; Kim, Sun-Hee; Kang, Chi-Dug

    2011-01-01

    Natural killer (NK) cells are important innate effector cells which can irradicate tumor cells through specific interactions between activating receptors on NK cells and their cognate ligands on cancer cells. Recently, it has been known that induction of activating NKG2D ligands including MHC class I chain-related (MIC) and UL16-binding protein (ULBP) families on tumor cells by various stresses makes them more susceptible to NK cell-mediated cytotoxicity. Therefore, it was investigated whether sublethal dose of hematoporphyrin-based photodynamic therapy (PDT) could up-regulate NKG2D ligands on tumor cells and increase the susceptibility of cancer cells against NK cells. Treatment with sublethal dose of hematoporphyrin-based PDT increased mRNA transcription and surface expression of ULBP1 and ULBP2 genes in SNU-1 human gastric tumor cell line and MICA/B, ULBP1, ULBP2 and ULBP3 genes in SW-900 human lung cancer cell line. These results were followed by increased susceptibility of cancer cells to NK cell-mediated cytotoxicity after sublethal PDT, which was abolished by addition of a blocking NKG2D mAb. Therefore, it could be suggested that the effect of hematoporphyrin-based PDT might be mediated in part by the increased susceptibility to NK cells via induction of NKG2D ligands on tumor cells, which survived after treatment with PDT.

  17. Inhibition of oxidative stress-elicited AKT activation facilitates PPARγ agonist-mediated inhibition of stem cell character and tumor growth of liver cancer cells.

    Directory of Open Access Journals (Sweden)

    Lanlan Liu

    Full Text Available Emerging evidence suggests that tumor-initiating cells (TICs are the most malignant cell subpopulation in tumors because of their resistance to chemotherapy or radiation treatment. Targeting TICs may be a key innovation for cancer treatment. In this study, we found that PPARγ agonists inhibited the cancer stem cell-like phenotype and attenuated tumor growth of human hepatocellular carcinoma (HCC cells. Reactive oxygen species (ROS initiated by NOX2 upregulation were partially responsible for the inhibitory effects mediated by PPARγ agonists. However, PPARγ agonist-mediated ROS production significantly activated AKT, which in turn promoted TIC survival by limiting ROS generation. Inhibition of AKT, by either pharmacological inhibitors or AKT siRNA, significantly enhanced PPARγ agonist-mediated inhibition of cell proliferation and stem cell-like properties in HCC cells. Importantly, in nude mice inoculated with HCC Huh7 cells, we demonstrated a synergistic inhibitory effect of the PPARγ agonist rosiglitazone and the AKT inhibitor triciribine on tumor growth. In conclusion, we observed a negative feedback loop between oxidative stress and AKT hyperactivation in PPARγ agonist-mediated suppressive effects on HCCs. Combinatory application of an AKT inhibitor and a PPARγ agonist may provide a new strategy for inhibition of stem cell-like properties in HCCs and treatment of liver cancer.

  18. Actomyosin-mediated cellular tension drives increased tissue stiffness and beta-catenin activation to induce epidermal hyperplasia and tumor growth

    NARCIS (Netherlands)

    Samuel, M.S.; Lopez, J.I.; McGhee, E.J.; Croft, D.R.; Strachan, D.; Timpson, P.; Munro, J.; Schroder, E.; Zhou, J.; Brunton, V.; Barker, N.; Clevers, H.; Sansom, O.J.; Anderson, K.I.; Weaver, V.M.; Olson, M.F.

    2011-01-01

    Tumors and associated stroma manifest mechanical properties that promote cancer. Mechanosensation of tissue stiffness activates the Rho/ROCK pathway to increase actomyosin-mediated cellular tension to re-establish force equilibrium. To determine how actomyosin tension affects tissue homeostasis and

  19. Ultrasound-Mediated Drug/Gene Delivery in Solid Tumor Treatment

    Directory of Open Access Journals (Sweden)

    Yufeng Zhou

    2013-01-01

    Full Text Available Ultrasound is an emerging modality for drug delivery in chemotherapy. This paper reviews this novel technology by first introducing the designs and characteristics of three classes of drug/gene vehicles, microbubble (including nanoemulsion, liposomes, and micelles. In comparison to conventional free drug, the targeted drug-release and delivery through vessel wall and interstitial space to cancerous cells can be activated and enhanced under certain sonication conditions. In the acoustic field, there are several reactions of these drug vehicles, including hyperthermia, bubble cavitation, sonoporation, and sonodynamics, whose physical properties are illustrated for better understanding of this approach. In vitro and in vivo results are summarized, and future directions are discussed. Altogether, ultrasound-mediated drug/gene delivery under imaging guidance provides a promising option in cancer treatment with enhanced agent release and site specificity and reduced toxicity.

  20. Timosaponin AIII induces antiplatelet and antithrombotic activity via Gq-mediated signaling by the thromboxane A2 receptor

    Science.gov (United States)

    Cong, Yue; Wang, Limei; Peng, Renjun; Zhao, Yang; Bai, Fan; Yang, Chao; Liu, Xiaolan; Wang, Daqian; Ma, Baiping; Cong, Yuwen

    2016-01-01

    The thromboxane (Tx) A2 pathway is a major contributor to the amplification of initial platelet activation and is therefore a key drug target. To identify potent small-molecule inhibitors of the thromboxane prostaglandin (TP) receptor, we screened a small steroidal saponin library using U46619-induced rat platelet aggregation assays. Timosaponin AIII (TAIII) was identified as a potent inhibitor of U46619-induced rat platelet aggregation and exhibited superior selectivity for the TP receptor versus other G protein-coupled receptors and a PKC activator. TAIII inhibited U46619-induced rat platelet aggregation independent of increases in cAMP and cGMP and the inhibition of TxA2 production. Both PKC and PLC activators restored TAIII-inhibited platelet aggregation, whereas TAIII did not inhibit platelet aggregation induced by co-activation of the G12/13 and Gz pathways. Furthermore, TAIII did not affect the platelet shape change or ROCK2 phosphorylation evoked by low-dose U46619. In vivo, TAIII prolonged tail bleeding time, reduced the mortality of animals with acute pulmonary thromboembolism and significantly reduced venous thrombus weight. Our study suggests that TAIII, by preferentially targeting Gq-mediated PLC/PKC signaling from the TP receptor, induces stronger in vitro antiplatelet activity and in vivo antithrombotic effects and may be an excellent candidate for the treatment of thrombotic disorders. PMID:27934923

  1. Suppression of IRF4 by IRF1, 3, and 7 in Noxa expression is a necessary event for IFN-γ-mediated tumor elimination.

    Science.gov (United States)

    Piya, Sujan; Moon, Ae Ran; Song, Peter I; Hiscott, John; Lin, Rongtuan; Seol, Dai-Wu; Kim, Tae-Hyoung

    2011-10-01

    IFN-γ plays a critical role in tumor immunosurveillance by affecting either immune cells or tumor cells; however, IFN-mediated effects on tumor elimination are largely unknown. In this study, we showed that IFN regulatory factors (IRF) modulated by IFNs up- and downregulated Noxa expression, a prodeath BH3 protein, in various cancer cells. Inhibition of Noxa expression using short hairpin RNA in tumor cells leads to resistance against lipopolysaccharide (LPS)-induced tumor elimination, in which IFN-γ is known as a critical effecter in mice. Chromatin immunoprecipitation analysis in both CT26 cells and SP2/0 cells, sensitive and resistant to LPS-induced tumor elimination, respectively, revealed that the responsiveness of IRF1, 3, 4, and 7 in the Noxa promoter region in response to IFN-γ might be crucial in LPS-induced tumor elimination. IRF1, 3, and 7 were upregulated by IFN-γ and activated Noxa expression, leading to the death of Noxa wild-type baby mouse kidney (BMK) cells but not of Noxa-deficient BMK cells. In contrast, IRF4 acts as a repressor for Noxa expression and inhibits cell death induced by IRF1, 3, or 7. Therefore, although IFN-γ alone are not able to induce cell death in tumor cells in vitro, Noxa induction by IFN-γ, which is regulated by the balance between its activators (IRF1, 3, and 7) and its repressor (IRF4), is crucial to increasing the susceptibility of tumor cells to immune cell-mediated cytotoxicity.

  2. Targeting mitochondria by α-tocopheryl succinate overcomes hypoxia-mediated tumor cell resistance to treatment.

    Science.gov (United States)

    Kulikov, Andrey V; Vdovin, Alexander S; Zhivotovsky, Boris; Gogvadze, Vladimir

    2014-06-01

    Rapidly proliferating tumor cells easily become hypoxic. This results in acquired stability towards treatment with anticancer drugs. Here, we show that cells grown at 0.1 % oxygen are more resistant towards treatment with the conventionally used anticancer drugs doxorubicin and cisplatin. The stimulation of apoptosis, as assessed by the number of cells in the SubG1 fraction of the cell cycle, release of cytochrome c into the cytosol, activation of caspase-3, and cleavage of PARP, was markedly suppressed under low oxygen content or when hypoxia was mimicked by deferoxamine. Hypoxia or deferoxamine treatment was accompanied by stabilization of the hypoxia-inducible factor (HIF-1). The downregulation of HIF-1 using siRNA technique restored cell sensitivity to treatment under hypoxic conditions to the levels detected under normoxic conditions. In contrast to cisplatin or doxorubicin, α-tocopheryl succinate (α-TOS), a compound that targets mitochondria, stimulated cell death irrespective of the oxygen concentration. Moreover, under hypoxic condition cell death induced by α-TOS was even enhanced. Thus, α-TOS can successfully overcome resistance to treatment caused by hypoxia, which makes α-TOS an attractive candidate for antitumor therapy via mitochondrial targeting.

  3. Tumor necrosis factor alpha inhibits in vitro bovine embryo development through a prostaglandin mediated mechanism

    Directory of Open Access Journals (Sweden)

    Jackson Lauren R

    2012-03-01

    Full Text Available Abstract Mastitis or other infectious diseases have been related to reduced fertility in cattle. Inflammatory cytokines such as tumor necrosis factor α (TNFα are released in response to infection and may have negative effects on embryo development. In the current study the effect of exposure to TNFα on the development of in vitro fertilized bovine embryos was examined. Indomethacin, a prostaglandin synthesis inhibitor, was used to determine if blockade of prostaglandin synthesis would alter the effects of TNFα. Ovaries were obtained from a local abattoir and immature COC were isolated from 2-10 mm follicles, in vitro matured and fertilized. After fertilization, groups of presumptive zygotes were randomly placed into either control development medium, medium containing 25 ng/mL TNFα or medium containing 25 ng/mL TNFα plus 1 μg/mL indomethacin. The proportion of blastocysts formed was assessed at day 7 of culture. Fewer embryos exposed to TNFα alone reached the blastocyst stage (17.5 ± 2.4%, P

  4. The phzA2-G2 transcript exhibits direct RsmA-mediated activation in Pseudomonas aeruginosa M18.

    Directory of Open Access Journals (Sweden)

    Bin Ren

    Full Text Available In bacteria, RNA-binding proteins of the RsmA/CsrA family act as post-transcriptional regulators that modulate translation initiation at target transcripts. The Pseudomonas aeruginosa genome contains two phenazine biosynthetic (phz gene clusters, phzA1-G1 (phz1 and phzA2-G2 (phz2, each of which is responsible for phenazine-1-carboxylic acid (PCA biosynthesis. In the present study, we show that RsmA exhibits differential gene regulation on two phz clusters in P. aeruginosa M18 at the post-transcriptional level. Based on the sequence analysis, four GGA motifs, the potential RsmA binding sites, are found on the 5'-untranslated region (UTR of the phz2 transcript. Studies with a series of lacZ reporter fusions, and gel mobility shift assays suggest that the third GGA motif (S3, located 21 nucleotides upstream of the Shine-Dalgarno (SD sequence, is involved in direct RsmA-mediated activation of phz2 expression. We therefore propose a novel model in which the binding of RsmA to the target S3 results in the destabilization of the stem-loop structure and the enhancement of ribosome access. This model could be fully supported by RNA structure prediction, free energy calculations, and nucleotide replacement studies. In contrast, various RsmA-mediated translation repression mechanisms have been identified in which RsmA binds near the SD sequence of target transcripts, thereby blocking ribosome access. Similarly, RsmA is shown to negatively regulate phz1 expression. Our new findings suggest that the differential regulation exerted by RsmA on the two phz clusters may confer an advantage to P. aeruginosa over other pseudomonads containing only a single phz cluster in their genomes.

  5. Re-evaluation of the kidney tumors and renal histopathology occurring in a 2-year rat carcinogenicity bioassay of quercetin.

    Science.gov (United States)

    Hard, Gordon C; Seely, John Curtis; Betz, Laura J; Hayashi, Shim-Mo

    2007-04-01

    Renal histopathology in the most recent 2-year carcinogenicity bioassay of quercetin, in Fischer 344 rats, was re-evaluated in an attempt to determine a mode of action underlying a small increase in renal tubule tumors reported in the males (). The re-evaluation confirmed the reported increase in renal tumors in mid- and high-dose males, including a single carcinoma in a high-dose male, as well as an exacerbation of spontaneous, chronic progressive nephropathy (CPN) in male rats only. The re-evaluation also showed that there were no cellular alterations in the kidney indicative of chemical toxicity at 6 months, 15 months, or 2 years. The evidence linked the occurrence of the predominant basophilic adenomas and foci of atypical tubule hyperplasia (ATH) with the exacerbation of CPN to advanced grades of severity, supporting a mode of action involving quercetin interaction with CPN. This mode of action represents a secondary mechanism for renal tumor development, with no relevance for extrapolation to humans. In addition, the single carcinoma present in the high-dose males, along with 4 other lesions ranging from ATH to adenoma in male and female groups, were considered to have a unique phenotype associated previously with neoplasms of spontaneous and familial origin.

  6. Cancer cell specific cytotoxic gene expression mediated by ARF tumor suppressor promoter constructs

    Energy Technology Data Exchange (ETDEWEB)

    Kurayoshi, Kenta [Department of Bioscience, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337 (Japan); Ozono, Eiko [Centre for Molecular Oncology, Barts Cancer Institute, Queen Mary, University of London, John Vane Science Centre, Charterhouse Square, London EC1M 6BQ (United Kingdom); Iwanaga, Ritsuko; Bradford, Andrew P. [Department of Obstetrics and Gynecology, University of Colorado School of Medicine, Anschutz Medical Campus, 12800 East 19th Avenue, Aurora, CO 80045 (United States); Komori, Hideyuki [Center for Stem Cell Biology, Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109 (United States); Ohtani, Kiyoshi, E-mail: btm88939@kwansei.ac.jp [Department of Bioscience, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337 (Japan)

    2014-07-18

    Highlights: • ARF promoter showed higher responsiveness to deregulated E2F activity than the E2F1 promoter. • ARF promoter showed higher cancer cell-specificity than E2F1 promoter to drive gene expression. • HSV-TK driven by ARF promoter showed higher cancer cell-specific cytotoxicity than that driven by E2F1 promoter. - Abstract: In current cancer treatment protocols, such as radiation and chemotherapy, side effects on normal cells are major obstacles to radical therapy. To avoid these side effects, a cancer cell-specific approach is needed. One way to specifically target cancer cells is to utilize a cancer specific promoter to express a cytotoxic gene (suicide gene therapy) or a viral gene required for viral replication (oncolytic virotherapy). For this purpose, the selected promoter should have minimal activity in normal cells to avoid side effects, and high activity in a wide variety of cancers to obtain optimal therapeutic efficacy. In contrast to the AFP, CEA and PSA promoters, which have high activity only in a limited spectrum of tumors, the E2F1 promoter exhibits high activity in wide variety of cancers. This is based on the mechanism of carcinogenesis. Defects in the RB pathway and activation of the transcription factor E2F, the main target of the RB pathway, are observed in almost all cancers. Consequently, the E2F1 promoter, which is mainly regulated by E2F, has high activity in wide variety of cancers. However, E2F is also activated by growth stimulation in normal growing cells, suggesting that the E2F1 promoter may also be highly active in normal growing cells. In contrast, we found that the tumor suppressor ARF promoter is activated by deregulated E2F activity, induced by forced inactivation of pRB, but does not respond to physiological E2F activity induced by growth stimulation. We also found that the deregulated E2F activity, which activates the ARF promoter, is detected only in cancer cell lines. These observations suggest that ARF promoter

  7. Tumor suppressor SPOP mediates the proteasomal degradation of progesterone receptors (PRs) in breast cancer cells.

    Science.gov (United States)

    Gao, Kun; Jin, Xiaofeng; Tang, Yan; Ma, Jian; Peng, Jingtiao; Yu, Long; Zhang, Pingzhao; Wang, Chenji

    2015-01-01

    Progesterone induces proliferation of breast cancer cells and contributes to the development of breast cancer. The effects of progesterone are mediated by progesterone receptors (PRs). However, it is still not fully understood how the proliferative effects of PR is regulated in vivo. Increasing amount of evidence strongly suggests that dysregulation of ubiquitin-proteasome system is closely associated with cancer pathogenesis. Speckle-type POZ protein (SPOP) is an adaptor protein of the CUL3-based E3 ubiquitin ligase complexes. SPOP represents one of the highest loci for loss of heterozygosity (LOH) in breast cancer. SPOP downregulation contributes to breast cancer cell growth and invasion. In this study, we revealed PR as a bona fide substrate for SPOP. SPOP interacts with PR in vivo and targets PR for ubiquitin-dependent proteasomal degradation. Moreover, SPOP suppresses progesteroneinduced PR transactivation, S phase entry, and Erk1/2 activation. Our study revealed novel molecular mechanisms underlying the regulation of PR protein homeostasis in breast cancer cells, and provided insights in understanding the relationship between SPOP inactivation and the development of breast cancer.

  8. PI3K/Akt signaling mediated Hexokinase-2 expression inhibits cell apoptosis and promotes tumor growth in pediatric osteosarcoma

    Energy Technology Data Exchange (ETDEWEB)

    Zhuo, Baobiao; Li, Yuan; Li, Zhengwei; Qin, Haihui; Sun, Qingzeng; Zhang, Fengfei; Shen, Yang; Shi, Yingchun [Department of Surgery, The Children' s Hospital of Xuzhou, Xuzhou, Jiangsu Province 221006 (China); Wang, Rong, E-mail: wangrong2008163@163.com [Department of Ultrasonography, Affiliated Hospital of Xuzhou Medical College, Xuzhou, Jiangsu Province 221006 (China)

    2015-08-21

    Accumulating evidence has shown that PI3K/Akt pathway is frequently hyperactivated in osteosarcoma (OS) and contributes to tumor initiation and progression. Altered phenotype of glucose metabolism is a key hallmark of cancer cells including OS. However, the relationship between PI3K/Akt pathway and glucose metabolism in OS remains largely unexplored. In this study, we showed that elevated Hexokinase-2 (HK2) expression, which catalyzes the first essential step of glucose metabolism by conversion of glucose into glucose-6-phosphate, was induced by activated PI3K/Akt signaling. Immunohistochemical analysis showed that HK2 was overexpressed in 83.3% (25/30) specimens detected and was closely correlated with Ki67, a cell proliferation index. Silencing of endogenous HK2 resulted in decreased aerobic glycolysis as demonstrated by reduced glucose consumption and lactate production. Inhibition of PI3K/Akt signaling also suppressed aerobic glycolysis and this effect can be reversed by reintroduction of HK2. Furthermore, knockdown of HK2 led to increased cell apoptosis and reduced ability of colony formation; meanwhile, these effects were blocked by 2-Deoxy-D-glucose (2-DG), a glycolysis inhibitor through its actions on hexokinase, indicating that HK2 functions in cell apoptosis and growth were mediated by altered aerobic glycolysis. Taken together, our study reveals a novel relationship between PI3K/Akt signaling and aerobic glycolysis and indicates that PI3K/Akt/HK2 might be potential therapeutic approaches for OS. - Highlights: • PI3K/Akt signaling contributes to elevated expression of HK2 in osteosarcoma. • HK2 inhibits cell apoptosis and promotes tumor growth through enhanced Warburg effect. • Inhibition of glycolysis blocks the oncogenic activity of HK2.

  9. Socioeconomic disparities in the quality of life in children with cancer or brain tumors: the mediating role of family factors.

    Science.gov (United States)

    Litzelman, Kristin; Barker, Emily; Catrine, Kristine; Puccetti, Diane; Possin, Peggy; Witt, Whitney P

    2013-05-01

    This study aimed to determine if and to what extent (i) socioeconomic disparities exist in the health-related quality of life (QOL) of children with cancer or brain tumors and healthy children; and (ii) family functioning and burden mediate the relationship between socioeconomic status and children's QOL. In this cross-sectional study, parents of children ages 2-18 with (n = 71) and without (n = 135) cancer or brain tumors completed in-person interviewer-assisted surveys assessing sociodemographics (including income and parental education), child QOL (measure: PedsQL), family functioning (measure: Family Adaptability and Cohesion Evaluation Scale IV) and burden (measure: Impact on the Family Scale). For children with cancer, clinical characteristics were captured through medical record abstraction. Multiple linear regression was used to determine the relationship between income and child QOL; the interaction between group status and income was assessed. Staged multivariate regression models were used to assess the role of family factors in this relationship among children with cancer. In multivariate analyses, the effect of income differed by cancer status; lower income was associated with worse QOL in children with cancer but not among healthy children. Among children with cancer, this relationship was significantly attenuated by family burden. Significant socioeconomic disparities exist in the QOL of children with cancer. Family factors partially explain the relationship between low income and poor QOL outcomes among these children. Lower-income families may have fewer resources to cope with their child's cancer. Increased support, monitoring, and referrals to reduce burden for these families may lead to improved QOL in children with cancer. Copyright © 2012 John Wiley & Sons, Ltd.

  10. Elevated snail expression mediates tumor progression in areca quid chewing-associated oral squamous cell carcinoma via reactive oxygen species.

    Directory of Open Access Journals (Sweden)

    Shiuan-Shinn Lee

    Full Text Available BACKGROUND: Snail is an important transcription factor implicated in several tumor progression and can be induced by reactive oxygen species (ROS. Areca quid chewing is a major risk factor of oral squamous cell carcinoma (OSCC. Therefore, we hypothesize that the major areca nut alkaloid arecoline may induce Snail via ROS and involve in the pathogenesis of areca quid chewing-associated OSCC. METHODOLOGY/PRINCIPAL FINDING: Thirty-six OSCC and ten normal oral epithelium specimens were examined by immunohistochemistry and analyzed by the clinico-pathological profiles. Cytotoxicity, 2', 7'-dichlorofluorescein diacetate assay, and western blot were used to investigate the effects of arecoline in human oral keratinocytes (HOKs and oral epithelial cell line OECM-1 cells. In addition, antioxidants N-acetyl-L-cysteine (NAC, curcumin, and epigallocatechin-3 gallate (EGCG were added to find the possible regulatory mechanisms. Initially, Snail expression was significantly higher in OSCC specimens (p<0.05. Elevated Snail expression was associated with lymph node metastasis (p = 0.031 and poor differentiation (p = 0.017. Arecoline enhanced the generation of intracellular ROS at the concentration higher than 40 µg/ml (p<0.05. Arecoline was also found to induced Snail expression in a dose- and time-dependent manner (p<0.05. Treatment with NAC, curcumin, and EGCG markedly inhibited arecoline induced Snail expression (p<0.05. CONCLUSION/SIGNIFICANCE: Our results suggest that Snail overexpression in areca quid chewing-associated OSCC is associated with tumors differentiation and lymph node metastasis. Arecoline-upregulated Snail expression may be mediated by ROS generation. In addition, arecoline induced Snail expression was downregulated by NAC, curcumin, and EGCG.

  11. Galectin-3 mediates cross-talk between K-Ras and Let-7c tumor suppressor microRNA.

    Directory of Open Access Journals (Sweden)

    Ran Levy

    Full Text Available BACKGROUND: Galectin-3 (Gal-3 and active (GTP-bound K-Ras contribute to the malignant phenotype of many human tumors by increasing the rate of cell proliferation, survival, and migration. These Gal-3-mediated effects result from a selective binding to K-Ras.GTP, causing increased nanoclustering in the cell membrane and leading to robust Ras signaling. Regulation of the interactions between Gal-3 and active K-Ras is not fully understood. METHODS AND FINDINGS: To gain a better understanding of what regulates the critical interactions between these two proteins, we examined the role of Gal-3 in the regulation of K-Ras by using Gal-3-knockout mouse embryonic-fibroblasts (Gal-3-/- MEFs and/or Gal-3/Gal-1 double-knockout MEFs. We found that knockout of Gal-3 induced strong downregulation (∼60% of K-Ras and K-Ras.GTP. The downregulation was somewhat more marked in the double-knockout MEFs, in which we also detected robust inhibition(∼50% of ERK and Akt activation. These additional effects are probably attributable to inhibition of the weak interactions of K-Ras.GTP with Gal-1. Re-expression of Gal-3 reversed the phenotype of the Gal-3-/- MEFs and dramatically reduced the disappearance of K-Ras in the presence of cycloheximide to the levels seen in wild-type MEFs. Furthermore, phosphorylation of Gal-3 by casein kinase-1 (CK-1 induced translocation of Gal-3 from the nucleus to the cytoplasm and the plasma membrane, leading to K-Ras stabilization accompanied by downregulation of the tumor suppressor miRNA let-7c, known to negatively control K-Ras transcription. CONCLUSIONS: Our results suggest a novel cross-talk between Gal-3-mediated downregulation of let 7c microRNA (which in turn negatively regulates K-Ras transcription and elucidates the association among Gal-3 let-7c and K-Ras transcription/translation, cellular compartmentalization and activity.

  12. Sequential activation of protein kinase C isoforms by organic dust is mediated by tumor necrosis factor.

    Science.gov (United States)

    Wyatt, Todd A; Slager, Rebecca E; Heires, Arthur J; Devasure, Jane M; Vonessen, Susanna G; Poole, Jill A; Romberger, Debra J

    2010-06-01

    Dust samples collected from Nebraska swine confinement facilities (hog dust extract [HDE]) are known to elicit proinflammatory cytokine release from human bronchial epithelial (HBE) cells in vitro. This response involves the activation of two protein kinase C (PKC) isoforms: PKCalpha and PKCepsilon. Experiments were designed to investigate the relationship between the two isoenzymes and the degree to which each is responsible for cytokine release in HBE. Experiments also examined the contribution of TNF-alpha to IL-6 and IL-8 release. PKCalpha and PKCepsilon activities were inhibited using isoform-specific pharmacologic inhibitors and genetically modified dominant-negative (DN) expressing cell lines. Release of the proinflammatory cytokines IL-6, IL-8, and TNF-alpha was measured and PKC isoform activities assessed. We found that HDE stimulates PKCalpha activity by 1 hour, and within 6 hours the activity returns to baseline. PKCalpha-specific inhibitor or PKCalphaDN cells abolish this HDE-mediated effect. Both IL-6 and IL-8 release are likewise diminished under these conditions compared with normal HBE, and treatment with TNF-alpha-neutralizing antibody does not further inhibit cytokine release. In contrast, PKCepsilon activity was enhanced by 6 hours after HDE treatment. TNF-alpha blockade abrogated this effect. HDE-stimulated IL-6, but not IL-8 release in PKCepsilonDN cells. The concentration of TNF-alpha released by HDE-stimulated HBE is sufficient to have a potent cytokine-eliciting effect. A time course of TNF-alpha release suggests that TNF-alpha is produced after PKCalpha activation, but before PKCepsilon. These results suggest a temporal ordering of events responsible for the release of cytokines, which initiate and exacerbate inflammatory events in the airways of people exposed to agricultural dust.

  13. Helicobacter pylori enhances tumor necrosis factor-related apoptosis-inducing ligand-mediated apoptosis in human gastric epithelial cells

    Institute of Scientific and Technical Information of China (English)

    Yi-Ying Wu; Hwei-Fang Tsai; We-Cheng Lin; Ai-Hsiang Chou; Hui-Ting Chen; Jyh-Chin Yang; Ping-I Hsu; Ping-Ning Hsu

    2004-01-01

    AIM: To investigate the relations between tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and Helicobacter pylori(H pylori) infection in apoptosis of gastric epithelial cells and to assess the expression of TRAIL onthe surface of infiltrating T-cells in Hpylori-infected gastric mucosa.METHODS: Human gastric epithelial cell lines and primary gastric epithelial cells were co-cultured with H pylori in vitro, then recombinant TRAIL proteins were added to the culture. Apoptosis of gastric epithelial cells was determined by a specific ELISA for cell death. Infiltrating lymphocytes were isolated from H pylori-infected gastric mucosa, and expression of TRAIL in T cells was analyzed by flow cytometry.RESULTS: The apoptosis of gastric epithelial cell lines and primary human gastric epithelial cells was mildly increased by interaction with either TRAIL or H pylorialone. Interestingly,the apoptotic indices were markedly elevated when gastric epithelial cells were incubated with both TRAIL and H pylori (Control vsTRAIL and H pylori: 0.51±0.06 vs 2.29±0.27,P = 0.018). A soluble TRAIL receptor (DR4-Fc) could specifically block the TRAIL-mediated apoptosis. Further studies demonstrated that infiltrating T-cells in gastric mucosa expressed TRAIL on their surfaces, and the induction of TRAIL sensitivity by H pylori was dependent upon direct cell contact of viable bacteria, but not CagA and VacA of H pylori.CONCLUSION: H pylori can sensitize human gastric epithelial ceils and enhance susceptibility to TRAIL-mediated apoptosis. Modulation of host cell sensitivity to apoptosis by bacterial interaction adds a new dimension to the immunopathogenesis of H pylori infection.

  14. Protein phosphatase 2A mediates dormancy of glioblastoma multiforme-derived tumor stem-like cells during hypoxia.

    Directory of Open Access Journals (Sweden)

    Christoph P Hofstetter

    Full Text Available PURPOSE: The hypoxic microenvironment of glioblastoma multiforme (GBM is thought to increase resistance to cancer therapies. Recent evidence suggests that hypoxia induces protein phosphatase 2A (PP2A, a regulator of cell cycle and cell death. The effects of PP2A on GBM tumor cell proliferation and survival during hypoxic conditions have not been studied. EXPERIMENTAL DESIGN: Expression of PP2A subunits and HIF-α proteins was measured in 65 high-grade astrocytoma and 18 non-neoplastic surgical brain specimens by western blotting. PP2A activity was measured by an immunoprecipitation assay. For in vitro experiments, GBM-derived tumor stem cell-like cells (TSCs were exposed to severe hypoxia produced by either CoCl₂ or 1% O₂. PP2A activity was inhibited either by okadaic acid or by shRNA depletion of the PP2A C subunit. Effects of PP2A activity on cell cycle progression and cell survival during hypoxic conditions were assessed using flow cytometry. RESULTS: In our patient cohort, PP2A activity was positively correlated with HIF-1∝ protein expression (P = 0.002. Patients with PP2A activity levels above 160 pMP had significantly worse survival compared to patients with levels below this threshold (P = 0.002. PP2A activity was an independent predictor of survival on multivariable analysis (P = 0.009. In our in vitro experiments, we confirmed that severe hypoxia induces PP2A activity in TSCs 6 hours after onset of exposure. PP2A activity mediated G1/S phase growth inhibition and reduced cellular ATP consumption in hypoxic TSCs. Conversely, inhibition of PP2A activity led to increased cell proliferation, exhaustion of intracellular ATP, and accelerated P53-independent cell death of hypoxic TSCs. CONCLUSIONS: Our results suggest that PP2A activity predicts poor survival in GBM. PP2A appears to reduce the metabolic demand of hypoxic TSCs and enhances tumor cell survival. Modulation of PP2A may be a potential target for cancer therapy.

  15. Integrin-mediated traction force enhances paxillin molecular associations and adhesion dynamics that increase the invasiveness of tumor cells into a three-dimensional extracellular matrix.

    Science.gov (United States)

    Mekhdjian, Armen H; Kai, FuiBoon; Rubashkin, Matthew G; Prahl, Louis S; Przybyla, Laralynne M; McGregor, Alexandra L; Bell, Emily S; Barnes, J Matthew; DuFort, Christopher C; Ou, Guanqing; Chang, Alice C; Cassereau, Luke; Tan, Steven J; Pickup, Michael W; Lakins, Jonathan N; Ye, Xin; Davidson, Michael W; Lammerding, Jan; Odde, David J; Dunn, Alexander R; Weaver, Valerie M

    2017-06-01

    Metastasis requires tumor cells to navigate through a stiff stroma and squeeze through confined microenvironments. Whether tumors exploit unique biophysical properties to metastasize remains unclear. Data show that invading mammary tumor cells, when cultured in a stiffened three-dimensional extracellular matrix that recapitulates the primary tumor stroma, adopt a basal-like phenotype. Metastatic tumor cells and basal-like tumor cells exert higher integrin-mediated traction forces at the bulk and molecular levels, consistent with a motor-clutch model in which motors and clutches are both increased. Basal-like nonmalignant mammary epithelial cells also display an altered integrin adhesion molecular organization at the nanoscale and recruit a suite of paxillin-associated proteins implicated in invasion and metastasis. Phosphorylation of paxillin by Src family kinases, which regulates adhesion turnover, is similarly enhanced in the metastatic and basal-like tumor cells, fostered by a stiff matrix, and critical for tumor cell invasion in our assays. Bioinformatics reveals an unappreciated relationship between Src kinases, paxillin, and survival of breast cancer patients. Thus adoption of the basal-like adhesion phenotype may favor the recruitment of molecules that facilitate tumor metastasis to integrin-based adhesions. Analysis of the physical properties of tumor cells and integrin adhesion composition in biopsies may be predictive of patient outcome. © 2017 Mekhdjian, Kai, Rubashkin, et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  16. P-Selectin-Mediated Adhesion between Platelets and Tumor Cells Promotes Intestinal Tumorigenesis in Apc(Min/+) Mice.

    Science.gov (United States)

    Qi, Cuiling; Li, Bin; Guo, Simei; Wei, Bo; Shao, Chunkui; Li, Jialin; Yang, Yang; Zhang, Qianqian; Li, Jiangchao; He, Xiaodong; Wang, Lijing; Zhang, Yajie

    2015-01-01

    Studies have indicated that platelets play an important role in tumorigenesis, and an abundance of platelets accumulate in the ovarian tumor microenvironment outside the vasculature. However, whether cancer cells recruit platelets within intestinal tumors and how they signal adherent platelets to enter intestinal tumor tissues remain unknown. Here, we unexpectedly found that large numbers of platelets were deposited within human colorectal tumor specimens using immunohistochemical staining, and these platelets were fully associated with tumor development. We further report the robust adhesion of platelet aggregates to tumor cells within intestinal tumors, which occurs via a mechanism that is dependent on P-selectin (CD62P), a cell adhesion molecule that is abundantly expressed on activated platelets. Using spontaneous intestinal tumor mouse models, we determined that the genetic deletion of P-selectin suppressed intestinal tumor growth, which was rescued by the infusion of wild-type platelets but not P-selectin(-/-) platelets. Mechanistically, platelet adhesion to tumor cells induced the secretion of vascular endothelial growth factor (VEGF) to promote angiogenesis and accelerate intestinal tumor cell proliferation. Our results indicate that the adherence of platelets to tumor cells could promote tumor growth and metastasis. By targeting this platelet-tumor cell interaction, recombinant soluble P-selectin may have therapeutic value for the treatment of intestinal tumors.

  17. The Smac Mimetic BV6 Improves NK Cell-Mediated Killing of Rhabdomyosarcoma Cells by Simultaneously Targeting Tumor and Effector Cells

    Science.gov (United States)

    Fischer, Kyra; Tognarelli, Sara; Roesler, Stefanie; Boedicker, Cathinka; Schubert, Ralf; Steinle, Alexander; Klingebiel, Thomas; Bader, Peter; Fulda, Simone; Ullrich, Evelyn

    2017-01-01

    Rhabdomyosarcoma (RMS), the most common cancer of connective tissues in pediatrics, is often resistant to conventional therapies. One underlying mechanism of this resistance is the overexpression of Inhibitor of Apoptosis (IAP) proteins, leading to a dysfunctional cell death program within tumor cells. Smac mimetics (SM) are small molecules that can reactivate the cell death program by antagonizing IAP proteins and thereby compensating their overexpression. Here, we report that SM sensitize two RMS cell lines (RD and RH30) toward natural killer (NK) cell-mediated killing on the one hand, and increase the cytotoxic potential of NK cells on the other. The SM-induced sensitization of RH30 cells toward NK cell-mediated killing is significantly reduced through blocking tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) on NK cells prior to coculture. In addition, the presence of zVAD.fmk, a pancaspase inhibitor, rescues tumor cells from the increase in killing, indicating an apoptosis-dependent cell death. On the NK cell side, the presence of SM in addition to IL-2 during the ex vivo expansion leads to an increase in their cytotoxic activity against RH30 cells. This effect is mainly TNFα-dependent and partially mediated by NK cell activation, which is associated with transcriptional upregulation of NF-κB target genes such as IκBα and RelB. Taken together, our findings implicate that SM represent a novel double-hit strategy, sensitizing tumor and activating NK cells with one single drug.

  18. The microRNA miR-181c controls microglia-mediated neuronal apoptosis by suppressing tumor necrosis factor

    Directory of Open Access Journals (Sweden)

    Zhang Li

    2012-09-01

    Full Text Available Abstract Background Post-ischemic microglial activation may contribute to neuronal damage through the release of large amounts of pro-inflammatory cytokines and neurotoxic factors. The involvement of microRNAs (miRNAs in the pathogenesis of disorders related to the brain and central nervous system has been previously studied, but it remains unknown whether the production of pro-inflammatory cytokines is regulated by miRNAs. Methods BV-2 and primary rat microglial cells were activated by exposure to oxygen-glucose deprivation (OGD. Global cerebral ischemia was induced using the four-vessel occlusion (4-VO model in rats. Induction of pro-inflammatory and neurotoxic factors, such as tumor necrosis factor (TNF-α, interleukin (IL-1β, and nitric oxide (NO, were assessed by ELISA, immunofluorescence, and the Griess assay, respectively. The miRNA expression profiles of OGD-activated BV-2 cells were subsequently compared with the profiles of resting cells in a miRNA microarray. BV-2 and primary rat microglial cells were transfected with miR-181c to evaluate its effects on TNF-α production after OGD. In addition, a luciferase reporter assay was conducted to confirm whether TNF-α is a direct target of miR-181c. Results OGD induced BV-2 microglial activation in vitro, as indicated by the overproduction of TNF-α, IL-1β, and NO. Global cerebral ischemia/reperfusion injury induced microglial activation and the release of pro-inflammatory cytokines in the hippocampus. OGD also downregulated miR-181c expression and upregulated TNF-α expression. Overproduction of TNF-α after OGD-induced microglial activation provoked neuronal apoptosis, whereas the ectopic expression of miR-181c partially protected neurons from cell death caused by OGD-activated microglia. RNAinterference-mediated knockdown of TNF-α phenocopied the effect of miR-181c-mediated neuronal protection, whereas overexpression of TNF-α blocked the miR-181c-dependent suppression of apoptosis

  19. Folate receptor-mediated enhanced and specific delivery of far-red light-activatable prodrugs of combretastatin A-4 to FR-positive tumor.

    Science.gov (United States)

    Nkepang, Gregory; Bio, Moses; Rajaputra, Pallavi; Awuah, Samuel G; You, Youngjae

    2014-12-17

    We examined the concept of a novel prodrug strategy in which anticancer drug can be locally released by visible/near IR light, taking advantage of the photodynamic process and photo-unclick chemistry. Our most recently formulated prodrug of combretastatin A-4, Pc-(L-CA4)2, showed multifunctionality for fluorescence imaging, light-activated drug release, and the combined effects of PDT and local chemotherapy. In this formulation, L is a singlet oxygen cleavable linker. Here, we advanced this multifunctional prodrug by adding a tumor-targeting group, folic acid (FA). We designed and prepared four FA-conjugated prodrugs 1-4 (CA4-L-Pc-PEGn-FA: n = 0, 2, 18, ∼45) and one non-FA-conjugated prodrug 5 (CA4-L-Pc-PEG18-boc). Prodrugs 3 and 4 had a longer PEG spacer and showed higher hydrophilicity, enhanced uptake to colon 26 cells via FR-mediated mechanisms, and more specific localization to SC colon 26 tumors in Balb/c mice than prodrugs 1 and 2. Prodrug 4 also showed higher and more specific uptake to tumors, resulting in selective tumor damage and more effective antitumor efficacy than non-FA-conjugated prodrug 5. FR-mediated targeting seemed to be an effective strategy to spare normal tissues surrounding tumors in the illuminated area during treatment with this prodrug.

  20. Tumor-induced CD11b(+) Gr-1(+) myeloid-derived suppressor cells exacerbate immune-mediated hepatitis in mice in a CD40-dependent manner.

    Science.gov (United States)

    Kapanadze, Tamar; Medina-Echeverz, José; Gamrekelashvili, Jaba; Weiss, Jonathan M; Wiltrout, Robert H; Kapoor, Veena; Hawk, Nga; Terabe, Masaki; Berzofsky, Jay A; Manns, Michael P; Wang, Ena; Marincola, Francesco M; Korangy, Firouzeh; Greten, Tim F

    2015-04-01

    Immunosuppressive CD11b(+) Gr-1(+) myeloid-derived suppressor cells (MDSCs) accumulate in the livers of tumor-bearing (TB) mice. We studied hepatic MDSCs in two murine models of immune-mediated hepatitis. Unexpectedly, treatment of TB mice with Concanavalin A (Con A) or α-galactosylceramide resulted in increased alanine aminotransferase (ALT) and aspartate aminotransferase (AST) serum levels in comparison to tumor-free mice. Adoptive transfer of hepatic MDSCs into naïve mice exacerbated Con A induced liver damage. Hepatic CD11b(+) Gr-1(+) cells revealed a polarized proinflammatory gene signature after Con A treatment. An IFN-γ-dependent upregulation of CD40 on hepatic CD11b(+) Gr-1(+) cells along with an upregulation of CD80, CD86, and CD1d after Con A treatment was observed. Con A treatment resulted in a loss of suppressor function by tumor-induced CD11b(+) Gr-1(+) MDSCs as well as enhanced reactive oxygen species (ROS)-mediated hepatotoxicity. CD40 knockdown in hepatic MDSCs led to increased arginase activity upon Con A treatment and lower ALT/AST serum levels. Finally, blockade of arginase activity in Cd40(-/-) tumor-induced myeloid cells resulted in exacerbation of hepatitis and increased ROS production in vivo. Our findings indicate that in a setting of acute hepatitis, tumor-induced hepatic MDSCs act as proinflammatory immune effector cells capable of killing hepatocytes in a CD40-dependent manner.

  1. Free radical-derived quinone methide mediates skin tumor promotion by butylated hydroxytoluene hydroperoxide: expanded role for electrophiles in multistage carcinogenesis.

    Science.gov (United States)

    Guyton, K Z; Bhan, P; Kuppusamy, P; Zweier, J L; Trush, M A; Kensler, T W

    1991-01-01

    Free radical derivatives of peroxides, hydroperoxides, and anthrones are thought to mediate tumor promotion by these compounds. Further, the promoting activity of phorbol esters is attributed, in part, to their ability to stimulate the cellular generation of oxygen radicals. A hydroperoxide metabolite of butylated hydroxytoluene, 2,6-di-tert-butyl-4-hydroperoxyl-4-methyl-2,5-cyclohexadienone (BHTOOH), has previously been shown to be a tumor promoter in mouse skin. BHTOOH is extensively metabolized by murine keratinocytes to several radical species. The primary radical generated from BHTOOH is a phenoxyl radical that can disproportionate to form butylated hydroxytoluene quinone methide, a reactive electrophile. Since electrophilic species have not been previously postulated to mediate tumor promotion, the present study was undertaken to examine the role of this electrophile in the promoting activity of BHTOOH. The biological activities of two chemical analogs of BHTOOH, 4-trideuteromethyl-BHTOOH and 4-tert-butyl-BHTOOH, were compared with that of the parent compound. 4-Trideuteromethyl-BHTOOH and 4-tert-butyl-BHTOOH have a reduced ability or inability, respectively, to form a quinone methide; however, like the parent compound, they both generate a phenoxyl radical when incubated with keratinocyte cytosol. The potency of BHTOOH, 4-trideuteromethyl-BHTOOH, and 4-tert-butyl-BHTOOH as inducers of ornithine decarboxylase, a marker of tumor promotion, was commensurate with their capacity for generating butylated hydroxytoluene quinone methide. These initial results were confirmed in a two-stage tumor promotion protocol in female SENCAR mice. Together, these data indicate that a quinone methide is mediating tumor promotion by BHTOOH, providing direct evidence that an electrophilic intermediate can elicit this stage of carcinogenesis. PMID:1846971

  2. Elevated Snail Expression Mediates Tumor Progression in Areca Quid Chewing-Associated Oral Squamous Cell Carcinoma via Reactive Oxygen Species

    Science.gov (United States)

    Lee, Shiuan-Shinn; Tsai, Chung-Hung; Yu, Cheng-Chia; Chang, Yu-Chao

    2013-01-01

    Background Snail is an important transcription factor implicated in several tumor progression and can be induced by reactive oxygen species (ROS). Areca quid chewing is a major risk factor of oral squamous cell carcinoma (OSCC). Therefore, we hypothesize that the major areca nut alkaloid arecoline may induce Snail via ROS and involve in the pathogenesis of areca quid chewing-associated OSCC. Methodology/Principal Finding Thirty-six OSCC and ten normal oral epithelium specimens were examined by immunohistochemistry and analyzed by the clinico-pathological profiles. Cytotoxicity, 2′, 7′-dichlorofluorescein diacetate assay, and western blot were used to investigate the effects of arecoline in human oral keratinocytes (HOKs) and oral epithelial cell line OECM-1 cells. In addition, antioxidants N-acetyl-L-cysteine (NAC), curcumin, and epigallocatechin-3 gallate (EGCG) were added to find the possible regulatory mechanisms. Initially, Snail expression was significantly higher in OSCC specimens (pArecoline enhanced the generation of intracellular ROS at the concentration higher than 40 µg/ml (pArecoline was also found to induced Snail expression in a dose- and time-dependent manner (parecoline induced Snail expression (pArecoline-upregulated Snail expression may be mediated by ROS generation. In addition, arecoline induced Snail expression was downregulated by NAC, curcumin, and EGCG. PMID:23874481

  3. Interferon-gamma and tumor necrosis factor-alpha sensitize primarily resistant human endometrial stromal cells to Fas-mediated apoptosis

    DEFF Research Database (Denmark)

    Fluhr, Herbert; Krenzer, Stefanie; Stein, Gerburg M

    2007-01-01

    -mediated signaling during early implantation. Here we show that ESCs are primarily resistant to Fas-mediated apoptosis independently of their state of hormonal differentiation. Pre-treatment of ESCs with interferon (IFN)-gamma and tumor necrosis factor (TNF)-alpha sensitizes them to become apoptotic upon stimulation......-inhibitory protein (FLIP, CFLAR) expression in ESCs. Additionally, we observed an activation of caspase 3, caspase 8 and caspase 9 upon apoptotic Fas triggering. In summary, we demonstrate that IFN-gamma and TNF-alpha sensitize primarily apoptosis-resistant ESCs to Fas-mediated cell death. This might be due...... to an upregulation of Fas expression, and apoptosis seems to be mediated by active caspase 3, caspase 8 and caspase 9. The observed pro-apoptotic effect of IFN-gamma and TNF-alpha on ESCs could play an important role in the modulation of early implantation....

  4. Neurofibromatosis type 2 tumor suppressor protein, NF2, induces proteasome-mediated degradation of JC virus T-antigen in human glioblastoma.

    Directory of Open Access Journals (Sweden)

    Sarah Beltrami

    Full Text Available Neurofibromatosis type 2 protein (NF2 has been shown to act as tumor suppressor primarily through its functions as a cytoskeletal scaffold. However, NF2 can also be found in the nucleus, where its role is less clear. Previously, our group has identified JC virus (JCV tumor antigen (T-antigen as a nuclear binding partner for NF2 in tumors derived from JCV T-antigen transgenic mice. The association of NF2 with T-antigen in neuronal origin tumors suggests a potential role for NF2 in regulating the expression of the JCV T-antigen. Here, we report that NF2 suppresses T-antigen protein expression in U-87 MG human glioblastoma cells, which subsequently reduces T-antigen-mediated regulation of the JCV promoter. When T-antigen mRNA was quantified, it was determined that increasing expression of NF2 correlated with an accumulation of T-antigen mRNA; however, a decrease in T-antigen at the protein level was observed. NF2 was found to promote degradation of ubiquitin bound T-antigen protein via a proteasome dependent pathway concomitant with the accumulation of the JCV early mRNA encoding T-antigen. The interaction between T-antigen and NF2 maps to the FERM domain of NF2, which has been shown previously to be responsible for its tumor suppressor activity. Co-immunoprecipitation assays revealed a ternary complex among NF2, T-antigen, and the tumor suppressor protein, p53 within a glioblastoma cell line. Further, these proteins were detected in various degrees in patient tumor tissue, suggesting that these associations may occur in vivo. Collectively, these results demonstrate that NF2 negatively regulates JCV T-antigen expression by proteasome-mediated degradation, and suggest a novel role for NF2 as a suppressor of JCV T-antigen-induced cell cycle regulation.

  5. A Natural CCR2 Antagonist Relieves Tumor-associated Macrophage-mediated Immunosuppression to Produce a Therapeutic Effect for Liver Cancer

    Directory of Open Access Journals (Sweden)

    Wenbo Yao

    2017-08-01

    Full Text Available Hepatocellular carcinoma (HCC is a common malignant tumor in the digestive tract with limited therapeutic choices. Although sorafenib, an orally administered multikinase inhibitor, has produced survival benefits for patients with advanced HCC, favorable clinical outcomes are limited due to individual differences and resistance. The application of immunotherapy, a promising approach for HCC is urgently needed. Macrophage infiltration, mediated by the CCL2/CCR2 axis, is a potential immunotherapeutic target. Here, we report that a natural product from Abies georgei, named 747 and related in structure to kaempferol, exhibits sensitivity and selectivity as a CCR2 antagonist. The specificity of 747 on CCR2 was demonstrated via calcium flux, the binding domain of CCR2 was identified in an extracellular loop by chimera binding assay, and in vivo antagonistic activity of 747 was confirmed through a thioglycollate-induced peritonitis model. In animals, 747 elevated the number of CD8+ T cells in tumors via blocking tumor-infiltrating macrophage-mediated immunosuppression and inhibited orthotopic and subcutaneous tumor growth in a CD8+ T cell-dependent manner. Further, 747 enhanced the therapeutic efficacy of low-dose sorafenib without obvious toxicity, through elevating the numbers of intra-tumoral CD8+ T cells and increasing death of tumor cells. Thus, we have discovered a natural CCR2 antagonist and have provided a new perspective on development of this antagonist for treatment of HCC. In mouse models of HCC, 747 enhanced the tumor immunosuppressive microenvironment and potentiated the therapeutic effect of sorafenib, indicating that the combination of an immunomodulator with a chemotherapeutic drug could be a new approach for treating HCC.

  6. The Escape of Cancer from T Cell-Mediated Immune Surveillance: HLA Class I Loss and Tumor Tissue Architecture

    Science.gov (United States)

    Garrido, Federico; Perea, Francisco; Bernal, Mónica; Sánchez-Palencia, Abel; Aptsiauri, Natalia; Ruiz-Cabello, Francisco

    2017-01-01

    Tumor immune escape is associated with the loss of tumor HLA class I (HLA-I) expression commonly found in malignant cells. Accumulating evidence suggests that the efficacy of immunotherapy depends on the expression levels of HLA class I molecules on tumors cells. It also depends on the molecular mechanism underlying the loss of HLA expression, which could be reversible/“soft” or irreversible/“hard” due to genetic alterations in HLA, β2-microglobulin or IFN genes. Immune selection of HLA-I negative tumor cells harboring structural/irreversible alterations has been demonstrated after immunotherapy in cancer patients and in experimental cancer models. Here, we summarize recent findings indicating that tumor HLA-I loss also correlates with a reduced intra-tumor T cell infiltration and with a specific reorganization of tumor tissue. T cell immune selection of HLA-I negative tumors results in a clear separation between the stroma and the tumor parenchyma with leucocytes, macrophages and other mononuclear cells restrained outside the tumor mass. Better understanding of the structural and functional changes taking place in the tumor microenvironment may help to overcome cancer immune escape and improve the efficacy of different immunotherapeutic strategies. We also underline the urgent need for designing strategies to enhance tumor HLA class I expression that could improve tumor rejection by cytotoxic T-lymphocytes (CTL). PMID:28264447

  7. The Escape of Cancer from T Cell-Mediated Immune Surveillance: HLA Class I Loss and Tumor Tissue Architecture

    Directory of Open Access Journals (Sweden)

    Federico Garrido

    2017-02-01

    Full Text Available Tumor immune escape is associated with the loss of tumor HLA class I (HLA-I expression commonly found in malignant cells. Accumulating evidence suggests that the efficacy of immunotherapy depends on the expression levels of HLA class I molecules on tumors cells. It also depends on the molecular mechanism underlying the loss of HLA expression, which could be reversible/“soft” or irreversible/“hard” due to genetic alterations in HLA, β2-microglobulin or IFN genes. Immune selection of HLA-I negative tumor cells harboring structural/irreversible alterations has been demonstrated after immunotherapy in cancer patients and in experimental cancer models. Here, we summarize recent findings indicating that tumor HLA-I loss also correlates with a reduced intra-tumor T cell infiltration and with a specific reorganization of tumor tissue. T cell immune selection of HLA-I negative tumors results in a clear separation between the stroma and the tumor parenchyma with leucocytes, macrophages and other mononuclear cells restrained outside the tumor mass. Better understanding of the structural and functional changes taking place in the tumor microenvironment may help to overcome cancer immune escape and improve the efficacy of different immunotherapeutic strategies. We also underline the urgent need for designing strategies to enhance tumor HLA class I expression that could improve tumor rejection by cytotoxic T-lymphocytes (CTL.

  8. A combretastatin-mediated decrease in neutrophil concentration in peripheral blood and the impact on the anti-tumor activity of this drug in two different murine tumor models.

    Directory of Open Access Journals (Sweden)

    Anja Bille Bohn

    Full Text Available The vascular disrupting agent combretastatin A-4 disodium phosphate (CA4P induces fluctuations in peripheral blood neutrophil concentration. Because neutrophils have the potential to induce both vascular damage and angiogenesis we analyzed neutrophil involvement in the anti-tumoral effects of CA4P in C3H mammary carcinomas in CDF1 mice and in SCCVII squamous cell carcinomas in C3H/HeN mice. Flow cytometry analyses of peripheral blood before and up to 144 h after CA4P administration (25 and 250 mg/kg revealed a decrease 1 h after treatment, followed by an early (3-6 h and a late (>72 h increase in the granulocyte concentration. We suggest that the early increase (3-6 h in granulocyte concentration was caused by the initial decrease at 1 h and found that the late increase was associated with tumor size, and hence independent of CA4P. No alterations in neutrophil infiltration into the C3H tumor after CA4P treatment (25 and 250 mg/kg were found. Correspondingly, neutrophil depletion in vivo, using an anti-neutrophil antibody, followed by CA4P treatment (25 mg/kg did not increase the necrotic fraction in C3H tumors significantly. However, by increasing the CA4P dose to 250 mg/kg we found a significant increase of 359% in necrotic fraction when compared to neutrophil-depleted mice; in mice with no neutrophil depletion CA4P induced an 89% change indicating that the presence of neutrophils reduced the effect of CA4P. In contrast, neither CA4P nor 1A8 affected the necrotic fraction in the SCCVII tumors significantly. Hence, we suggest that the initial decrease in granulocyte concentration was caused by non-tumor-specific recruitment of neutrophils and that neutrophils may attenuate CA4P-mediated anti-tumor effect in some tumor models.

  9. Immunoregulation through IL-10 gene expression and the fate of cytotoxic T lymphocyte-mediated tumor immunotherapy

    Directory of Open Access Journals (Sweden)

    Chakraborty Nitya

    2009-01-01

    Full Text Available Gene analysis of tumor associated antigens revealed that tumor antigens are all normal gene product. Inducing tumor reactive cytotoxic T lymphocytes (CT in the patients is same as inducing autoimmunity in the patients. Immunosuppressive cytokine interleukin-10 (IL-10 plays an important role in maintaining homeostasis or tolerance. To break the tumor tolerance, blocking and IL-10 secretion or intervention in the pathways of IL-10 gene activation is indeed important.

  10. Adenosine A2B receptor-mediated leukemia inhibitory factor release from astrocytes protects cortical neurons against excitotoxicity

    Directory of Open Access Journals (Sweden)

    Moidunny Shamsudheen

    2012-08-01

    Full Text Available Abstract Background Neuroprotective and neurotrophic properties of leukemia inhibitory factor (LIF have been widely reported. In the central nervous system (CNS, astrocytes are the major source for LIF, expression of which is enhanced following disturbances leading to neuronal damage. How astrocytic LIF expression is regulated, however, has remained an unanswered question. Since neuronal stress is associated with production of extracellular adenosine, we investigated whether LIF expression in astrocytes was mediated through adenosine receptor signaling. Methods Mouse cortical neuronal and astrocyte cultures from wild-type and adenosine A2B receptor knock-out animals, as well as adenosine receptor agonists/antagonists and various enzymatic inhibitors, were used to study LIF expression and release in astrocytes. When needed, a one-way analysis of variance (ANOVA followed by Bonferroni post-hoc test was used for statistical analysis. Results We show here that glutamate-stressed cortical neurons induce LIF expression through activation of adenosine A2B receptor subtype in cultured astrocytes and require signaling of protein kinase C (PKC, mitogen-activated protein kinases (MAPKs: p38 and ERK1/2, and the nuclear transcription factor (NF-κB. Moreover, LIF concentration in the supernatant in response to 5′-N-ethylcarboxamide (NECA stimulation was directly correlated to de novo protein synthesis, suggesting that LIF release did not occur through a regulated release pathway. Immunocytochemistry experiments show that LIF-containing vesicles co-localize with clathrin and Rab11, but not with pHogrin, Chromogranin (CgA and CgB, suggesting that LIF might be secreted through recycling endosomes. We further show that pre-treatment with supernatants from NECA-treated astrocytes increased survival of cultured cortical neurons against glutamate, which was absent when the supernatants were pre-treated with an anti-LIF neutralizing antibody. Conclusions

  11. T cell-mediated antitumor immune response eliminates skin tumors induced by mouse papillomavirus, MmuPV1.

    Science.gov (United States)

    Joh, Joongho; Chilton, Paula M; Wilcher, Sarah A; Zahin, Maryam; Park, Jino; Proctor, Mary L; Ghim, Shin-Je; Jenson, Alfred B

    2017-09-19

    Previous studies of naturally occurring mouse papillomavirus (PV) MmuPV1-induced tumors in B6.Cg-Foxn1(nu/nu) mice suggest that T cell deficiency is necessary and sufficient for the development of such tumors. To confirm this, MmuPV1-induced tumors were transplanted from T cell-deficient mice into immunocompetent congenic mice. Consequently, the tumors regressed and eventually disappeared. The elimination of MmuPV1-infected skin/tumors in immunocompetent mice was consistent with the induction of antitumor T cell immunity. This was confirmed by adoptive cell experiments using hyperimmune splenocytes collected from graft-recipient mice. In the present study, such splenocytes were injected into T cell-deficient mice infected with MmuPV1, and they eliminated both early-stage and fully formed tumors. We clearly show that anti-tumor T cell immunity activated during tumor regression in immunocompetent mice effectively eliminates tumors developing in T cell-deficient congenic mice. The results corroborate the notion that PV-induced tumors are strongly linked to the immune status of the host, and that PV antigens are major anti-tumor antigens. Successful anti-PV T cell responses should, therefore, lead to effective anti-tumor immune therapy in human PV-infected patients. Copyright © 2017. Published by Elsevier Inc.

  12. The NRF2-mediated oxidative stress response pathway is associated with tumor cell resistance to arsenic trioxide across the NCI-60 panel

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    Liu Qian

    2010-08-01

    Full Text Available Abstract Background Drinking water contaminated with inorganic arsenic is associated with increased risk for different types of cancer. Paradoxically, arsenic trioxide can also be used to induce remission in patients with acute promyelocytic leukemia (APL with a success rate of approximately 80%. A comprehensive study examining the mechanisms and potential signaling pathways contributing to the anti-tumor properties of arsenic trioxide has not been carried out. Methods Here we applied a systems biology approach to identify gene biomarkers that underlie tumor cell responses to arsenic-induced cytotoxicity. The baseline gene expression levels of 14,500 well characterized human genes were associated with the GI50 data of the NCI-60 tumor cell line panel from the developmental therapeutics program (DTP database. Selected biomarkers were tested in vitro for the ability to influence tumor susceptibility to arsenic trioxide. Results A significant association was found between the baseline expression levels of 209 human genes and the sensitivity of the tumor cell line panel upon exposure to arsenic trioxide. These genes were overlayed onto protein-protein network maps to identify transcriptional networks that modulate tumor cell responses to arsenic trioxide. The analysis revealed a significant enrichment for the oxidative stress response pathway mediated by nuclear factor erythroid 2-related factor 2 (NRF2 with high expression in arsenic resistant tumor cell lines. The role of the NRF2 pathway in protecting cells against arsenic-induced cell killing was validated in tumor cells using shRNA-mediated knock-down. Conclusions In this study, we show that the expression level of genes in the NRF2 pathway serve as potential gene biomarkers of tumor cell responses to arsenic trioxide. Importantly, we demonstrate that tumor cells that are deficient for NRF2 display increased sensitivity to arsenic trioxide. The results of our study will be useful in

  13. The Retinoblastoma Tumor Suppressor Protein (pRb)/E2 Promoter Binding Factor 1 (E2F1) Pathway as a Novel Mediator of TGFβ-induced Autophagy.

    Science.gov (United States)

    Korah, Juliana; Canaff, Lucie; Lebrun, Jean-Jacques

    2016-01-29

    TGFβ is a multifunctional cytokine that regulates cell proliferation, cell immortalization, and cell death, acting as a key homeostatic mediator in various cell types and tissues. Autophagy is a programmed mechanism that plays a pivotal role in controlling cell fate and, consequently, many physiological and pathological processes, including carcinogenesis. Although autophagy is often considered a pro-survival mechanism that renders cells viable in stressful conditions and thus might promote tumor growth, emerging evidence suggests that autophagy is also a tumor suppressor pathway. The relationship between TGFβ signaling and autophagy is context-dependent and remains unclear. TGFβ-mediated activation of autophagy has recently been suggested to contribute to the growth inhibitory effect of TGFβ in hepatocarcinoma cells. In the present study, we define a novel process of TGFβ-mediated autophagy in cancer cell lines of various origins. We found that autophagosome initiation and maturation by TGFβ is dependent on the retinoblastoma tumor suppressor protein/E2 promoter binding factor (pRb/E2F1) pathway, which we have previously established as a critical signaling axis leading to various TGFβ tumor suppressive effects. We further determined that TGFβ induces pRb/E2F1-dependent transcriptional activation of several autophagy-related genes. Together, our findings reveal that TGFβ induces autophagy through the pRb/E2F1 pathway and transcriptional activation of autophagy-related genes and further highlight the central relevance of the pRb/E2F1 pathway downstream of TGFβ signaling in tumor suppression.

  14. Distinct domains of M-T2, the myxoma virus tumor necrosis factor (TNF) receptor homolog, mediate extracellular TNF binding and intracellular apoptosis inhibition.

    OpenAIRE

    Schreiber, M; Sedger, L; McFadden, G

    1997-01-01

    The myxoma virus tumor necrosis factor (TNF) receptor homolog, M-T2, is expressed both as a secreted glycoprotein that inhibits the cytolytic activity of rabbit TNF-alpha and as an endoglycosidase H-sensitive intracellular species that prevents myxoma virus-infected CD4+ T lymphocytes from undergoing apoptosis. To compare the domains of M-T2 mediating extracellular TNF inhibition and intracellular apoptosis inhibition, recombinant myxoma viruses expressing nested C-terminal truncations of M-T...

  15. Soluble interleukin 6 receptor (sIL-6R) mediates colonic tumor cell adherence to the vascular endothelium: a mechanism for metastatic initiation?

    LENUS (Irish Health Repository)

    Dowdall, J F

    2012-02-03

    The mechanisms by which surgery increases metastatic proliferation remain poorly characterized, although endotoxin and immunocytes play a role. Recent evidence suggests that endothelial adherence of tumor cells may be important in the formation of metastases. Soluble receptors of interleukin-6 (sIL-6R) shed by activated neutrophils exert IL-6 effects on endothelial cells, which are unresponsive under normal circumstances. This study examined the hypothesis that sIL-6R released by surgical stress increases tumor cell adherence to the endothelium. Neutrophils (PMN) were stimulated with lipopolysaccharide, C-reactive protein (CRP), and tumor necrosis factor-alpha. Soluble IL-6R release was measured by enzyme-linked immunosorbent assay. Colonic tumor cells transfected with green fluorescent protein and endothelial cells were exposed to sIL-6R, and tumor cell adherence and transmigration were measured by fluorescence microscopy. Basal release of sIL-6R from PMN was 44.7 +\\/- 8.2 pg\\/ml at 60 min. This was significantly increased by endotoxin and CRP (131 +\\/- 16.8 and 84.1 +\\/- 5.3, respectively; both P < 0.05). However, tumor necrosis factor-alpha did not significantly alter sIL-6R release. Endothelial and tumor cell exposure to sIL-6R increased tumor cell adherence by 71.3% within 2 h but did not significantly increase transmigration, even at 6 h. Mediators of surgical stress induce neutrophil release of a soluble receptor for IL-6 that enhances colon cancer cell endothelial adherence. Since adherence to the endothelium is now considered to be a key event in metastatic genesis, these findings have important implications for colon cancer treatment strategies.

  16. ETS2 mediated tumor suppressive function and MET oncogene inhibition in human non-small cell lung cancer

    Science.gov (United States)

    Kabbout, Mohamed; Garcia, Melinda M.; Fujimoto, Junya; Liu, Diane D.; Woods, Denise; Chow, Chi-Wan; Mendoza, Gabriela; Momin, Amin A.; James, Brian P.; Solis, Luisa; Behrens, Carmen; Lee, J. Jack

    2013-01-01

    PURPOSE The ETS2 transcription factor is an evolutionarily conserved gene that is deregulated in cancer. We analyzed the transcriptome of lung adenocarcinomas and normal lung tissue by expression profiling and found that ETS2 was significantly down-regulated in adenocarcinomas. In this study, we probed the yet unknown functional role of ETS2 in lung cancer pathogenesis. EXPERIMENTAL DESIGN Lung adenocarcinomas (n=80) and normal lung tissues (n=30) were profiled using the Affymetrix Human Gene 1.0 ST platform. Immunohistochemical (IHC) analysis was performed to determine ETS2 protein expression in NSCLC histological tissue specimens (n=201). Patient clinical outcome, based on ETS2 IHC expression, was statistically assessed using the log-rank and Kaplan-Meier tests. RNA interference and over-expression strategies were employed to assess effects of ETS2 expression on the transcriptome and on various malignant phenotypes. RESULTS ETS2 expression was significantly reduced in lung adenocarcinomas compared to normal lung (precurrence in NSCLC (p=0.009, HR=1.89) and adenocarcinoma (p=0.03, HR=1.86). Moreover, ETS2 was found to significantly inhibit lung cancer cell growth, migration and invasion (p<0.05), and microarray and pathways analysis revealed significant (p<0.001) activation of the HGF pathway following ETS2 knockdown. In addition, ETS2 was found to suppress MET phosphorylation and knockdown of MET expression significantly attenuated (p<0.05) cell invasion mediated by ETS2-specific siRNA. Furthermore, knockdown of ETS2 augmented HGF-induced MET phosphorylation, cell migration and invasion. CONCLUSION(S) Our findings point to a tumor suppressor role for ETS2 in human NSCLC pathogenesis through inhibition of the MET proto-oncogene. PMID:23659968

  17. Menin: a tumor suppressor that mediates postsynaptic receptor expression and synaptogenesis between central neurons of Lymnaea stagnalis.

    Directory of Open Access Journals (Sweden)

    Nichole Flynn

    Full Text Available Neurotrophic factors (NTFs support neuronal survival, differentiation, and even synaptic plasticity both during development and throughout the life of an organism. However, their precise roles in central synapse formation remain unknown. Previously, we demonstrated that excitatory synapse formation in Lymnaea stagnalis requires a source of extrinsic NTFs and receptor tyrosine kinase (RTK activation. Here we show that NTFs such as Lymnaea epidermal growth factor (L-EGF act through RTKs to trigger a specific subset of intracellular signalling events in the postsynaptic neuron, which lead to the activation of the tumor suppressor menin, encoded by Lymnaea MEN1 (L-MEN1 and the expression of excitatory nicotinic acetylcholine receptors (nAChRs. We provide direct evidence that the activation of the MAPK/ERK cascade is required for the expression of nAChRs, and subsequent synapse formation between pairs of neurons in vitro. Furthermore, we show that L-menin activation is sufficient for the expression of postsynaptic excitatory nAChRs and subsequent synapse formation in media devoid of NTFs. By extending our findings in situ, we reveal the necessity of EGFRs in mediating synapse formation between a single transplanted neuron and its intact presynaptic partner. Moreover, deficits in excitatory synapse formation following EGFR knock-down can be rescued by injecting synthetic L-MEN1 mRNA in the intact central nervous system. Taken together, this study provides the first direct evidence that NTFs functioning via RTKs activate the MEN1 gene, which appears sufficient to regulate synapse formation between central neurons. Our study also offers a novel developmental role for menin beyond tumour suppression in adult humans.

  18. Menin: A Tumor Suppressor That Mediates Postsynaptic Receptor Expression and Synaptogenesis between Central Neurons of Lymnaea stagnalis

    Science.gov (United States)

    Flynn, Nichole; Getz, Angela; Visser, Frank; Janes, Tara A.; Syed, Naweed I.

    2014-01-01

    Neurotrophic factors (NTFs) support neuronal survival, differentiation, and even synaptic plasticity both during development and throughout the life of an organism. However, their precise roles in central synapse formation remain unknown. Previously, we demonstrated that excitatory synapse formation in Lymnaea stagnalis requires a source of extrinsic NTFs and receptor tyrosine kinase (RTK) activation. Here we show that NTFs such as Lymnaea epidermal growth factor (L-EGF) act through RTKs to trigger a specific subset of intracellular signalling events in the postsynaptic neuron, which lead to the activation of the tumor suppressor menin, encoded by Lymnaea MEN1 (L-MEN1) and the expression of excitatory nicotinic acetylcholine receptors (nAChRs). We provide direct evidence that the activation of the MAPK/ERK cascade is required for the expression of nAChRs, and subsequent synapse formation between pairs of neurons in vitro. Furthermore, we show that L-menin activation is sufficient for the expression of postsynaptic excitatory nAChRs and subsequent synapse formation in media devoid of NTFs. By extending our findings in situ, we reveal the necessity of EGFRs in mediating synapse formation between a single transplanted neuron and its intact presynaptic partner. Moreover, deficits in excitatory synapse formation following EGFR knock-down can be rescued by injecting synthetic L-MEN1 mRNA in the intact central nervous system. Taken together, this study provides the first direct evidence that NTFs functioning via RTKs activate the MEN1 gene, which appears sufficient to regulate synapse formation between central neurons. Our study also offers a novel developmental role for menin beyond tumour suppression in adult humans. PMID:25347295

  19. Do Deviant Peer Associations Mediate the Contributions of Self-Esteem to Problem Behavior During Early Adolescence? A 2-Year Longitudinal Study

    Science.gov (United States)

    DuBois, David L.; Silverthorn, Naida

    2004-01-01

    We investigated deviant peer associations as a mediator of the influences of general and peer-oriented self-esteem on problem behavior using data from a 2-year longitudinal study of 350 young adolescents. Measures of problem behavior included substance use (alcohol use, smoking) and antisocial behavior (fighting, stealing). Using latent growth…

  20. Maraviroc decreases CCL8-mediated migration of CCR5(+) regulatory T cells and reduces metastatic tumor growth in the lungs.

    Science.gov (United States)

    Halvorsen, E C; Hamilton, M J; Young, A; Wadsworth, B J; LePard, N E; Lee, H N; Firmino, N; Collier, J L; Bennewith, K L

    2016-06-01

    Regulatory T cells (Tregs) play a crucial physiological role in the regulation of immune homeostasis, although recent data suggest Tregs can contribute to primary tumor growth by suppressing antitumor immune responses. Tregs may also influence the development of tumor metastases, although there is a paucity of information regarding the phenotype and function of Tregs in metastatic target organs. Herein, we demonstrate that orthotopically implanted metastatic mammary tumors induce significant Treg accumulation in the lungs, which is a site of mammary tumor metastasis. Tregs in the primary tumor and metastatic lungs express high levels of C-C chemokine receptor type 5 (CCR5) relative to Tregs in the mammary fat pad and lungs of tumor-free mice, and Tregs in the metastatic lungs are enriched for CCR5 expression in comparison to other immune cell populations. We also identify that C-C chemokine ligand 8 (CCL8), an endogenous ligand of CCR5, is produced by F4/80(+) macrophages in the lungs of mice with metastatic primary tumors. Migration of Tregs toward CCL8 ex vivo is reduced in the presence of the CCR5 inhibitor Maraviroc. Importantly, treatment of mice with Maraviroc (MVC) reduces the level of CCR5(+) Tregs and metastatic tumor burden in the lungs. This work provides evidence of a CCL8/CCR5 signaling axis driving Treg recruitment to the lungs of mice bearing metastatic primary tumors, representing a potential therapeutic target to decrease Treg accumulation and metastatic tumor growth.

  1. Tumor-derived mural-like cells coordinate with endothelial cells: role of YKL-40 in mural cell-mediated angiogenesis.

    Science.gov (United States)

    Francescone, R; Ngernyuang, N; Yan, W; Bentley, B; Shao, R

    2014-04-17

    Tumor neo-vasculature is characterized by spatial coordination of endothelial cells with mural cells, which delivers oxygen and nutrients. Here, we explored a key role of the secreted glycoprotein YKL-40, a mesenchymal marker, in the interaction between endothelial cells and mesenchymal mural-like cells for tumor angiogenesis. Xenotransplantation of tumor-derived mural-like cells (GSDCs) expressing YKL-40 in mice developed extensive and stable blood vessels covered with more GSDCs than those in YKL-40 gene knockdown tumors. YKL-40 expressed by GSDCs was associated with increased interaction of neural cadherin/β-catenin/smooth muscle alpha actin; thus, mediating cell-cell adhesion and permeability. YKL-40 also induced the interaction of vascular endothelial cadherin/β-catenin/actin in endothelial cells (HMVECs). In cell co-culture systems, YKL-40 enhanced both GSDC and HMVEC contacts, restricted vascular leakage, and stabilized vascular networks. Collectively, the data inform new mechanistic insights into the cooperation of mural cells with endothelial cells induced by YKL-40 during tumor angiogenesis, and also enhance our understanding of YKL-40 in both mural and endothelial cell biology.

  2. 3-bromopyruvate and sodium citrate target glycolysis, suppress survivin, and induce mitochondrial-mediated apoptosis in gastric cancer cells and inhibit gastric orthotopic transplantation tumor growth.

    Science.gov (United States)

    Wang, Ting-An; Zhang, Xiao-Dong; Guo, Xing-Yu; Xian, Shu-Lin; Lu, Yun-Fei

    2016-03-01

    Glycolysis is the primary method utilized by cancer cells to produce the energy (adenosine triphosphate, ATP) required for cell proliferation. Therefore, inhibition of glycolysis may inhibit tumor growth. We previously found that both 3-bromopyruvate (3-BrPA) and sodium citrate (SCT) can inhibit glycolysis in vitro; however, the underlying inhibitory mechanisms remain unclear. In the present study, we used a human gastric cancer cell line (SGC-7901) and an orthotopic transplantation tumor model in nude mice to explore the specific mechanisms of 3-BrPA and SCT. We found that both 3-BrPA and SCT effectively suppressed cancer cell proliferation, arrested the cell cycle, induced apoptosis, and decreased the production of lactate and ATP. 3-BrPA significantly reduced the glycolytic enzyme hexokinase activity, while SCT selectively inhibited phosphofructokinase-1 activity. Furthermore, 3-BrPA and SCT upregulated the expression of pro-apoptotic proteins (Bax, cytochrome c, and cleaved caspase-3) and downregulated the expression of anti-apoptotic proteins (Bcl-2 and survivin). Finally, our animal model of gastric cancer indicated that intraperitoneal injection of 3-BrPA and SCT suppressed orthotopic transplantation tumor growth and induced tumor apoptosis. Taken together, these results suggest that 3-BrPA and SCT selectively suppress glycolytic enzymes, decrease ATP production, induce mitochondrial-mediated apoptosis, downregulate survivin, and inhibit tumor growth. Moreover, an intraperitoneal injection is an effective form of administration of 3-BrPA and SCT.

  3. Brain tumor-targeted therapy by systemic delivery of siRNA with Transferrin receptor-mediated core-shell nanoparticles.

    Science.gov (United States)

    Wei, Lin; Guo, Xi-Ying; Yang, Ting; Yu, Min-Zhi; Chen, Da-Wei; Wang, Jian-Cheng

    2016-08-20

    Treatment of brain tumor remains a great challenge worldwide. Development of a stable, safe, and effective siRNA delivery system which is able to cross the impermeable blood-brain barrier (BBB) and target glioma cells is necessary. This study aims to investigate the therapeutic effects of intravenous administration of T7 peptide modified core-shell nanoparticles (named T7-LPC/siRNA NPs) on brain tumors. Layer-by-layer assembling of protamine/chondroitin sulfate/siRNA/cationic liposomes followed by T7 peptide modification has been carried out in order to obtain a targeted siRNA delivery system. In vitro cellular uptake experiments demonstrated a higher intracellular fluorescence intensity of siRNA in brain microvascular endothelial cells (BMVECs) and U87 glioma cells when treated with T7-LPC/siRNA NPs compared with PEG-LPC/siRNA NPs. In the co-culture model of BMVECs and U87 cells, a significant down-regulation of EGFR protein expression occurred in the U87 glioma cells after treatment with the T7-LPC/siEGFR NPs. Moreover, the T7-LPC/siRNA NPs had an advantage in penetrating into a deep region of the tumor spheroid compared with PEG-LPC/siRNA NPs. In vivo imaging revealed that T7-LPC/siRNA NPs accumulated more specifically in brain tumor tissues than the non-targeted NPs. Also, in vivo tumor therapy experiments demonstrated that the longest survival period along with the greatest downregulation of EGFR expression in tumor tissues was observed in mice with an intracranial U87 glioma treated with T7-LPC/siEGFR NPs compared with mice receiving other formulations. Therefore, we believe that these transferrin receptor-mediated core-shell nanoparticles are an important potential siRNA delivery system for brain tumor-targeted therapy.

  4. CXCR5(+)CD8(+) T cells present elevated capacity in mediating cytotoxicity toward autologous tumor cells through interleukin 10 in diffuse large B-cell lymphoma.

    Science.gov (United States)

    Tang, Jiahong; Zha, Jie; Guo, Xutao; Shi, Pengcheng; Xu, Bing

    2017-09-01

    Diffuse large B-cell lymphoma (DLBCL) is a common and aggressive subtype of non-Hodgkin's lymphomas, with limited treatment options in refractory and relapsed patients. Growing evidence supports the notion that CD8(+) T cell immunity could be utilized to eliminate B cell lymphomas. CXCR5(+)CD8(+) T cell is a novel cell subtype and share CXCR5 expression with CD19(+) tumor cells. In this study, we investigated the frequency and function of existing CXCR5(+)CD8(+) T cells in DLBCL patients. We found that DLBCL patients as a group demonstrated significantly higher level of CXCR5(+)CD8(+) T cells than healthy individuals, with huge variability in each patient. Using anti-CD3/CD28-stimulated CD8(+) T cells as effector (E) cells and autologous CD19(+) tumor cells as target (T) cells, at high E:T ratio, no difference between the intensities of CXCR5(+)CD8(+) T cell- and CXCR5(-)CD8(+) T cell-mediated cytotoxicity were observed. However, at intermediate and low E:T ratios, the CXCR5(+)CD8(+) T cells presented stronger cytotoxicity than CXCR5(-)CD8(+) T cells. The expressions of granzyme A, granzyme B, and perforin were significantly higher in CXCR5(+)CD8(+) T cells than in CXCR5(-)CD8(+) T cells, with no significant difference in the level of degranulation. Tumor cells in DLBCL were known to secrete high level of interleukin 10 (IL-10). We therefore blocked the IL-10/IL-10R pathway, and found that the expressions of granzyme A, granzyme B, and perforin by CXCR5(+)CD8(+) T cells were significantly elevated. Together, these results suggest that CXCR5(+)CD8(+) T cells are potential candidates of CD8(+) T cell-based immunotherapies, could mediate elimination of autologous tumor cells in DLBCL patients, but are also susceptible to IL-10-mediated suppression. Copyright © 2017. Published by Elsevier B.V.

  5. Gene therapy with tumor-specific promoter mediated suicide gene plus IL-12 gene enhanced tumor inhibition and prolonged host survival in a murine model of Lewis lung carcinoma.

    Science.gov (United States)

    Xu, Yu; Hou, Jinxuan; Liu, Zhengchun; Yu, Haijun; Sun, Wenjie; Xiong, Jie; Liao, Zhengkai; Zhou, Fuxiang; Xie, Conghua; Zhou, Yunfeng

    2011-04-11

    Gene therapy is a promising therapeutic approach for cancer. Targeted expression of desired therapeutic proteins within the tumor is the best approach to reduce toxicity and improve survival. This study is to establish a more effective and less toxic gene therapy of cancer. Combined gene therapy strategy with recombinant adenovirus expressing horseradish peroxidase (HRP) mediated by human telomerase reverse transcriptase (hTERT) promoter (AdhTERTHRP) and murine interleukin-12 (mIL-12) under the control of Cytomegalovirus (CMV) promoter (AdCMVmIL-12) was developed and evaluated against Lewis lung carcinoma (LLC) both in vivo and in vitro. The mechanism of action and systemic toxicities were also investigated. The combination of AdhTERTHRP/indole-3-acetic acid (IAA) treatment and AdCMVmIL-12 resulted in significant tumor growth inhibition and survival improvement compared with AdhTERTHRP/IAA alone (tumor volume, 427.4 ± 48.7 mm3 vs 581.9 ± 46.9 mm3, p = 0.005 on day 15; median overall survival (OS), 51 d vs 33 d) or AdCMVmIL-12 alone (tumor volume, 362.2 ± 33.8 mm3 vs 494.4 ± 70.2 mm3, p = 0.046 on day 12; median OS, 51 d vs 36 d). The combination treatment stimulated more CD4+ and CD8+ T lymphocyte infiltration in tumors, compared with either AdCMVmIL-12 alone (1.3-fold increase for CD4+ T cells and 1.2-fold increase for CD8+ T cells, P gene therapy with AdhTERTHRP/IAA and AdCMVmIL-12 could significantly inhibit tumor growth and improve host survival in LLC model, without significant systemic adverse effects.

  6. Adenovirus-mediated expression of pig α(1, 3) galactosyltransferase reconstructs Gal α(1, 3) Gal epitope on the surface of human tumor cells

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Gal α(1,3)Gal(gal epitope)is a carbohydrate epitope and synthesized in large amount by α(1,3)galactosyltransferase [α(1,3)GT] enzyme on the cells of lower mammalian animals such as pigs and mice.Human has no gal epitope due to the inactivation of α(1,3)GT gene but produces a large amount of antibodies(anti-Gal)which recognize Gal α(1,3)Gal structures specifically.In this study,a replicationdeficient recombinant adenoviral vector Ad5sGT containing pig α(1,3)GT cDNA was constructed and characterized.Adenoviral vector-mediated transfer of pig α(1,3)GT gene into human tumor cells such as malignant melanoma A375,stomach cancer SGC-7901,and lung cancer SPC-A-1 was reported for the first time.Results showed that Gal epitope did not increase the sensitivity of human tumor cells to human complement-mediated lysis,although human complement activation and the binding of human IgG and IgM natural antibodies to human tumor cells were enhanced significantly after Ad5sGT transduction.Appearance of gal epitope on the human tumor cells changed the expression of cell surface carbohydrates reacting with Ulex europaeus I(UEA I)lectins,Vicia villosa agglutinin(VVA),Arachis hypogaea agglutinin(PNA),and Glycine max agglutinin(SBA)to different degrees.In addition,no effect of gal epitope on the growth in vitro of human tumor cells was observed in MTT assay.

  7. Disulfiram (DSF) acts as a copper ionophore to induce copper-dependent oxidative stress and mediate anti-tumor efficacy in inflammatory breast cancer.

    Science.gov (United States)

    Allensworth, Jennifer L; Evans, Myron K; Bertucci, François; Aldrich, Amy J; Festa, Richard A; Finetti, Pascal; Ueno, Naoto T; Safi, Rachid; McDonnell, Donald P; Thiele, Dennis J; Van Laere, Steven; Devi, Gayathri R

    2015-06-01

    Cancer cells often have increased levels of reactive oxygen species (ROS); however, acquisition of redox adaptive mechanisms allows for evasion of ROS-mediated death. Inflammatory breast cancer (IBC) is a distinct, advanced BC subtype characterized by high rates of residual disease and recurrence despite advances in multimodality treatment. Using a cellular model of IBC, we identified an oxidative stress response (OSR) signature in surviving IBC cells after administration of an acute dose of an ROS inducer. Metagene analysis of patient samples revealed significantly higher OSR scores in IBC tumor samples compared to normal or non-IBC tissues, which may contribute to the poor response of IBC tumors to common treatment strategies, which often rely heavily on ROS induction. To combat this adaptation, we utilized a potent redox modulator, the FDA-approved small molecule Disulfiram (DSF), alone and in combination with copper. DSF forms a complex with copper (DSF-Cu) increasing intracellular copper concentration both in vitro and in vivo, bypassing the need for membrane transporters. DSF-Cu antagonized NFκB signaling, aldehyde dehydrogenase activity and antioxidant levels, inducing oxidative stress-mediated apoptosis in multiple IBC cellular models. In vivo, DSF-Cu significantly inhibited tumor growth without significant toxicity, causing apoptosis only in tumor cells. These results indicate that IBC tumors are highly redox adapted, which may render them resistant to ROS-inducing therapies. DSF, through redox modulation, may be a useful approach to enhance chemo- and/or radio-sensitivity for advanced BC subtypes where therapeutic resistance is an impediment to durable responses to current standard of care.

  8. Tumor suppressor p16(INK4a) inhibits cancer cell growth by downregulating eEF1A2 through a direct interaction.

    Science.gov (United States)

    Lee, Mee-Hyun; Choi, Bu Young; Cho, Yong-Yeon; Lee, Sung-Young; Huang, Zunnan; Kundu, Joydeb Kumar; Kim, Myoung Ok; Kim, Dong Joon; Bode, Ann M; Surh, Young-Joon; Dong, Zigang

    2013-04-15

    The tumor suppressor protein p16(INK4a) is a member of the INK4 family of cyclin-dependent kinase (Cdk) inhibitors, which are involved in the regulation of the eukaryotic cell cycle. However, the mechanisms underlying the anti-proliferative effects of p16(INK4a) have not been fully elucidated. Using yeast two-hybrid screening, we identified the eukaryotic elongation factor (eEF)1A2 as a novel interacting partner of p16(INK4a). eEF1A2 is thought to function as an oncogene in cancers. The p16(INK4a) protein interacted with all but the D2 (250-327 aa) domain of eEF1A2. Ectopic expression of p16(INK4a) decreased the expression of eEF1A2 and inhibited cancer cell growth. Furthermore, suppression of protein synthesis by expression of p16(INK4a) ex vivo was verified by luciferase reporter activity. Microinjection of p16(INK4a) mRNA into the cytoplasm of Xenopus embryos suppressed the luciferase mRNA translation, whereas the combination of p16(INK4a) and morpholino-eEF1A2 resulted in a further reduction in translational activity. We conclude that the interaction of p16(INK4a) with eEF1A2, and subsequent downregulation of the expression and function of eEF1A2 is a novel mechanism explaining the anti-proliferative effects of p16(INK4a).

  9. T cell receptor (TCR-transgenic CD8 lymphocytes rendered insensitive to transforming growth factor beta (TGFβ signaling mediate superior tumor regression in an animal model of adoptive cell therapy

    Directory of Open Access Journals (Sweden)

    Quatromoni Jon G

    2012-06-01

    Full Text Available Abstract Tumor antigen-reactive T cells must enter into an immunosuppressive tumor microenvironment, continue to produce cytokine and deliver apoptotic death signals to affect tumor regression. Many tumors produce transforming growth factor beta (TGFβ, which inhibits T cell activation, proliferation and cytotoxicity. In a murine model of adoptive cell therapy, we demonstrate that transgenic Pmel-1 CD8 T cells, rendered insensitive to TGFβ by transduction with a TGFβ dominant negative receptor II (DN, were more effective in mediating regression of established B16 melanoma. Smaller numbers of DN Pmel-1 T cells effectively mediated tumor regression and retained the ability to produce interferon-γ in the tumor microenvironment. These results support efforts to incorporate this DN receptor in clinical trials of adoptive cell therapy for cancer.

  10. T-cell suppression mediated by regulatory T cells infiltrating hepatic tumors can be overcome by GITRL treatment

    NARCIS (Netherlands)

    A. Pedroza-Gonzalez (Alexander); J. Kwekkeboom (Jaap); D. Sprengers (Dave)

    2013-01-01

    textabstractRecently, we reported the accumulation of CD4+FOXP3+ regulatory T cells (Tregs) within the tumor mass of patients bearing liver cancer. Tumor-infiltrating Tregs (TiTreg) are active and potent suppressors of antitumor immunity. Importantly, treatment with GITR L reduced the immunosuppress

  11. Acquisition of tumor cell phenotypic diversity along the EMT spectrum under hypoxic pressure: Consequences on susceptibility to cell-mediated cytotoxicity.

    Science.gov (United States)

    Terry, Stéphane; Buart, Stéphanie; Tan, Tuan Zea; Gros, Gwendoline; Noman, Muhammad Zaeem; Lorens, James B; Mami-Chouaib, Fathia; Thiery, Jean Paul; Chouaib, Salem

    2017-01-01

    Tumor escape to immunosurveillance and resistance to immune attacks present a major hurdle in cancer therapy, especially in the current era of new cancer immunotherapies. We report here that hypoxia, a hallmark of most solid tumors, orchestrates carcinoma cell heterogeneity through the induction of phenotypic diversity and the acquisition of distinct epithelial-mesenchymal transition (EMT) states. Using lung adenocarcinoma cells derived from a non-metastatic patient, we demonstrated that hypoxic stress induced phenotypic diversity along the EMT spectrum, with induction of EMT transcription factors (EMT-TFs) SNAI1, SNAI2, TWIST1, and ZEB2 in a hypoxia-inducible factor-1α (HIF1A)-dependent or -independent manner. Analysis of hypoxia-exposed tumor subclones, with pronounced epithelial or mesenchymal phenotypes, revealed that mesenchymal subclones exhibited an increased propensity to resist cytotoxic T lymphocytes (CTL), and natural killer (NK) cell-mediated lysis by a mechanism involving defective immune synapse signaling. Additionally, targeting EMT-TFs, or inhibition of TGF-β signaling, attenuated mesenchymal subclone susceptibility to immune attack. Together, these findings uncover hypoxia-induced EMT and heterogeneity as a novel driving escape mechanism to lymphocyte-mediated cytotoxicity, with the potential to provide new therapeutic opportunities for cancer patients.

  12. Central CRTH2, a second prostaglandin D2 receptor, mediates emotional impairment in the lipopolysaccharide and tumor-induced sickness behavior model.

    Science.gov (United States)

    Haba, Ryota; Shintani, Norihito; Onaka, Yusuke; Kanoh, Takuya; Wang, Hyper; Takenaga, Risa; Hayata, Atsuko; Hirai, Hiroyuki; Nagata, Kin-ya; Nakamura, Masataka; Kasai, Atsushi; Hashimoto, Ryota; Nagayasu, Kazuki; Nakazawa, Takanobu; Hashimoto, Hitoshi; Baba, Akemichi

    2014-02-12

    Chemoattractant receptor-homologous molecule expressed on T helper type 2 cells (CRTH2) is a second prostaglandin D2 receptor involved in mediating the allergic response; however, its central function is not yet known. Here, we demonstrate that central CRTH2 mediates emotional impairment. Lipopolysaccharide (LPS)-induced decreases in social interaction and novel exploratory behavior were observed in wild-type (CRTH2(+/+)) mice but not CRTH2-deficient (CRTH2(-/-)) mice, but both genotypes showed hypolocomotion and anorexia following LPS injection. Tumor (colon 26) inoculation, a more pathologically relevant model, induced decreases in social interaction and novel exploratory behavior in CRTH2(+/+), but not CRTH2(-/-) mice. In addition, the CRTH2 antagonists including clinically available ramatroban reversed impaired social interaction and novel exploratory behavior after either LPS or tumor inoculation in CRTH2(+/+) mice. Finally, LPS-induced c-Fos expression in the hypothalamic paraventricular nucleus (PVN) and central amygdala (CeA) was selectively abolished in CRTH2(-/-) mice. These results show that CRTH2 participates in LPS-induced emotional changes and activation in the PVN and CeA. Our study provides the first evidence that central CRTH2 regulates specific emotional behaviors, and that CRTH2 antagonism has potential as a therapeutic target for behavioral symptoms associated with tumors and infectious diseases.

  13. T cells bearing a chimeric antigen receptor against prostate-specific membrane antigen mediate vascular disruption and result in tumor regression.

    Science.gov (United States)

    Santoro, Stephen P; Kim, Soorin; Motz, Gregory T; Alatzoglou, Dimitrios; Li, Chunsheng; Irving, Melita; Powell, Daniel J; Coukos, George

    2015-01-01

    Aberrant blood vessels enable tumor growth, provide a barrier to immune infiltration, and serve as a source of protumorigenic signals. Targeting tumor blood vessels for destruction, or tumor vascular disruption therapy, can therefore provide significant therapeutic benefit. Here, we describe the ability of chimeric antigen receptor (CAR)-bearing T cells to recognize human prostate-specific membrane antigen (hPSMA) on endothelial targets in vitro as well as in vivo. CAR T cells were generated using the anti-PSMA scFv, J591, and the intracellular signaling domains: CD3ζ, CD28, and/or CD137/4-1BB. We found that all anti-hPSMA CAR T cells recognized and eliminated PSMA(+) endothelial targets in vitro, regardless of the signaling domain. T cells bearing the third-generation anti-hPSMA CAR, P28BBζ, were able to recognize and kill primary human endothelial cells isolated from gynecologic cancers. In addition, the P28BBζ CAR T cells mediated regression of hPSMA-expressing vascular neoplasms in mice. Finally, in murine models of ovarian cancers populated by murine vessels expressing hPSMA, the P28BBζ CAR T cells were able to ablate PSMA(+) vessels, cause secondary depletion of tumor cells, and reduce tumor burden. Taken together, these results provide a strong rationale for the use of CAR T cells as agents of tumor vascular disruption, specifically those targeting PSMA. Cancer Immunol Res; 3(1); 68-84. ©2014 AACR. ©2014 American Association for Cancer Research.

  14. Trichostatin A Modulates Thiazolidinedione-Mediated Suppression of Tumor Necrosis Factor α-Induced Lipolysis in 3T3-L1 Adipocytes

    Science.gov (United States)

    Lu, Juu-Chin; Chang, Yu-Tzu; Wang, Chih-Tien; Lin, Yu-Chun; Lin, Chun-Ken; Wu, Zhong-Sheng

    2013-01-01

    In obesity, high levels of tumor necrosis factor α (TNFα) stimulate lipolysis in adipocytes, leading to hyperlipidemia and insulin resistance. Thiazolidinediones (TZDs), the insulin-sensitizing drugs, antagonize TNFα-induced lipolysis in adipocytes, thereby increasing insulin sensitivity in diabetes patients. The cellular target of TZDs is peroxisome proliferator-activated receptor γ (PPARγ), a nuclear receptor that controls many adipocyte functions. As a transcription factor, PPARγ is closely modulated by coregulators, which include coactivators and corepressors. Previous studies have revealed that in macrophages, the insulin-sensitizing effect of PPARγ may involve suppression of proinflammatory gene expression by recruiting the corepressor complex that contains corepressors and histone deacetylases (HDACs). Therefore, we investigated whether the corepressor complex is involved in TZD-mediated suppression of TNFα-induced lipolysis in 3T3-L1 adipocytes. Trichostatin A (TSA), a pan HDAC inhibitor (HDACI) that inhibits class I and II HDACs, was used to examine the involvement of HDACs in the actions of TZDs. TSA alone increased basal lipolysis and attenuated TZD-mediated suppression of TNFα-induced lipolysis. Increased basal lipolysis may in part result from class I HDAC inhibition because selective class I HDACI treatment had similar results. However, attenuation of TZD-mediated TNFα antagonism may be specific to TSA and related hydroxamate-based HDACI rather than to HDAC inhibition. Consistently, corepressor depletion did not affect TZD-mediated suppression. Interestingly, TSA treatment greatly reduced PPARγ levels in differentiated adipocytes. Finally, extracellular signal-related kinase 1/2 (ERK1/2) mediated TNFα-induced lipolysis, and TZDs suppressed TNFα-induced ERK phosphorylation. We determined that TSA increased basal ERK phosphorylation, and attenuated TZD-mediated suppression of TNFα-induced ERK phosphorylation, consistent with TSA

  15. Trichostatin A modulates thiazolidinedione-mediated suppression of tumor necrosis factor α-induced lipolysis in 3T3-L1 adipocytes.

    Science.gov (United States)

    Lu, Juu-Chin; Chang, Yu-Tzu; Wang, Chih-Tien; Lin, Yu-Chun; Lin, Chun-Ken; Wu, Zhong-Sheng

    2013-01-01

    In obesity, high levels of tumor necrosis factor α (TNFα) stimulate lipolysis in adipocytes, leading to hyperlipidemia and insulin resistance. Thiazolidinediones (TZDs), the insulin-sensitizing drugs, antagonize TNFα-induced lipolysis in adipocytes, thereby increasing insulin sensitivity in diabetes patients. The cellular target of TZDs is peroxisome proliferator-activated receptor γ (PPARγ), a nuclear receptor that controls many adipocyte functions. As a transcription factor, PPARγ is closely modulated by coregulators, which include coactivators and corepressors. Previous studies have revealed that in macrophages, the insulin-sensitizing effect of PPARγ may involve suppression of proinflammatory gene expression by recruiting the corepressor complex that contains corepressors and histone deacetylases (HDACs). Therefore, we investigated whether the corepressor complex is involved in TZD-mediated suppression of TNFα-induced lipolysis in 3T3-L1 adipocytes. Trichostatin A (TSA), a pan HDAC inhibitor (HDACI) that inhibits class I and II HDACs, was used to examine the involvement of HDACs in the actions of TZDs. TSA alone increased basal lipolysis and attenuated TZD-mediated suppression of TNFα-induced lipolysis. Increased basal lipolysis may in part result from class I HDAC inhibition because selective class I HDACI treatment had similar results. However, attenuation of TZD-mediated TNFα antagonism may be specific to TSA and related hydroxamate-based HDACI rather than to HDAC inhibition. Consistently, corepressor depletion did not affect TZD-mediated suppression. Interestingly, TSA treatment greatly reduced PPARγ levels in differentiated adipocytes. Finally, extracellular signal-related kinase 1/2 (ERK1/2) mediated TNFα-induced lipolysis, and TZDs suppressed TNFα-induced ERK phosphorylation. We determined that TSA increased basal ERK phosphorylation, and attenuated TZD-mediated suppression of TNFα-induced ERK phosphorylation, consistent with TSA's effects

  16. Trichostatin A modulates thiazolidinedione-mediated suppression of tumor necrosis factor α-induced lipolysis in 3T3-L1 adipocytes.

    Directory of Open Access Journals (Sweden)

    Juu-Chin Lu

    Full Text Available In obesity, high levels of tumor necrosis factor α (TNFα stimulate lipolysis in adipocytes, leading to hyperlipidemia and insulin resistance. Thiazolidinediones (TZDs, the insulin-sensitizing drugs, antagonize TNFα-induced lipolysis in adipocytes, thereby increasing insulin sensitivity in diabetes patients. The cellular target of TZDs is peroxisome proliferator-activated receptor γ (PPARγ, a nuclear receptor that controls many adipocyte functions. As a transcription factor, PPARγ is closely modulated by coregulators, which include coactivators and corepressors. Previous studies have revealed that in macrophages, the insulin-sensitizing effect of PPARγ may involve suppression of proinflammatory gene expression by recruiting the corepressor complex that contains corepressors and histone deacetylases (HDACs. Therefore, we investigated whether the corepressor complex is involved in TZD-mediated suppression of TNFα-induced lipolysis in 3T3-L1 adipocytes. Trichostatin A (TSA, a pan HDAC inhibitor (HDACI that inhibits class I and II HDACs, was used to examine the involvement of HDACs in the actions of TZDs. TSA alone increased basal lipolysis and attenuated TZD-mediated suppression of TNFα-induced lipolysis. Increased basal lipolysis may in part result from class I HDAC inhibition because selective class I HDACI treatment had similar results. However, attenuation of TZD-mediated TNFα antagonism may be specific to TSA and related hydroxamate-based HDACI rather than to HDAC inhibition. Consistently, corepressor depletion did not affect TZD-mediated suppression. Interestingly, TSA treatment greatly reduced PPARγ levels in differentiated adipocytes. Finally, extracellular signal-related kinase 1/2 (ERK1/2 mediated TNFα-induced lipolysis, and TZDs suppressed TNFα-induced ERK phosphorylation. We determined that TSA increased basal ERK phosphorylation, and attenuated TZD-mediated suppression of TNFα-induced ERK phosphorylation, consistent with

  17. Thromboxane A2 receptor-mediated release of matrix metalloproteinase-1 (MMP-1) induces expression of monocyte chemoattractant protein-1 (MCP-1) by activation of protease-activated receptor 2 (PAR2) in A549 human lung adenocarcinoma cells.

    Science.gov (United States)

    Li, Xiuling; Tai, Hsin-Hsiung

    2014-08-01

    Matrix metalloproteinases (MMPs) and monocyte chemoattractant protein-1 (MCP-1, CCL2) are known to be upregulated in many tumors. Their roles in tumor invasion and metastasis are being uncovered. How they are related to each other and involved in tumor progression remains to be determined. Earlier it was reported that I-BOP-initiated activation of thromboxane A2 receptor (TP) induced the release of MMP-1, MMP-3, and MMP-9 from lung cancer A549 cells overexpressing TPα (A549-TPα). Herein it was found that MMP-1, but not MMP-3 or MMP-9, induced the expression of MCP-1 in A549 cells. Conditioned medium (CM) from I-BOP activated, MMP-1 siRNA pretreated A549-TPα cells induced greatly attenuated expression of MCP-1 in A549 cells indicating that MMP-1 in the CM contributed significantly to the expression of MCP-1. MMP-1 was shown to activate protease-activated receptor 2 (PAR2) instead of commonly assumed PAR1 to increase the expression of MCP-1 in A549 cells. This conclusion was reached from the following findings: (1) expression of MCP-1 induced by trypsin, a PAR2 agonist, and also PAR2 agonist peptide, was inhibited by a PAR2 antagonist; (2) expression of MCP-1 induced by MMP-1 and by CM from I-BOP activated A549-TPα cells was blocked by a PAR2 antagonist but not by other PAR antagonists; (3) expression of MCP-1 induced by MMP-1 and by CM from I-BOP activated A549-TPα cells was attenuated significantly by pretreatment of cells with PAR2-siRNA. These results suggest that PAR2 is a novel MMP-1 target mediating MMP-1-induced signals in A549 lung cancer cells.

  18. ICAM-2 expression mediates a membrane-actin link, confers a nonmetastatic phenotype and reflects favorable tumor stage or histology in neuroblastoma.

    Directory of Open Access Journals (Sweden)

    Karina Jin Yoon

    Full Text Available The actin cytoskeleton is a primary determinant of tumor cell motility and metastatic potential. Motility and metastasis are thought to be regulated, in large part, by the interaction of membrane proteins with cytoplasmic linker proteins and of these linker proteins, in turn, with actin. However, complete membrane-to-actin linkages have been difficult to identify. We used co-immunoprecipitation and competitive peptide assays to show that intercellular adhesion molecule-2 (ICAM-2/alpha-actinin/actin may comprise such a linkage in neuroblastoma cells. ICAM-2 expression limited the motility of these cells and redistributed actin fibers in vitro, and suppressed development of disseminated tumors in an in vivo model of metastatic neuroblastoma. Consistent with these observations, immunohistochemical analysis demonstrated ICAM-2 expression in primary neuroblastoma tumors exhibiting features that are associated with limited metastatic disease and more favorable clinical outcome. In neuroblastoma cell lines, ICAM-2 expression did not affect AKT activation, tumorigenic potential or chemosensitivity, as has been reported for some types of transfected cells. The observed ICAM-2-mediated suppression of metastatic phenotype is a novel function for this protein, and the interaction of ICAM-2/alpha-actinin/actin represents the first complete membrane-linker protein-actin linkage to impact tumor cell motility in vitro and metastatic potential in an in vivo model. Current work focuses on identifying specific protein domains critical to the regulation of neuroblastoma cell motility and metastasis and on determining if these domains represent exploitable therapeutic targets.

  19. Both p53-PUMA/NOXA-Bax-mitochondrion and p53-p21cip1 pathways are involved in the CDglyTK-mediated tumor cell suppression

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Zhendong, E-mail: zdyu@hotmail.com [Department of Clinical laboratory, Peking University Shenzhen Hospital, Guangdong (China); Wang, Hao [Department of pathology, The Chinese University of Hong Kong, Hong Kong (China); Zhang, Libin; Tang, Aifa; Zhai, Qinna; Wen, Jianxiang; Yao, Li [Department of Clinical laboratory, Peking University Shenzhen Hospital, Guangdong (China); Li, Pengfei, E-mail: lipengfei@cuhk.edu.hk [Department of pathology, The Chinese University of Hong Kong, Hong Kong (China)

    2009-09-04

    CDglyTK fusion suicide gene has been well characterized to effectively kill tumor cells. However, the exact mechanism and downstream target genes are not fully understood. In our study, we found that CDglyTK/prodrug treatment works more efficiently in p53 wild-type (HONE1) cells than in p53 mutant (CNE1) cells. We then used adenovirus-mediated gene delivery system to either knockdown or overexpress p53 and its target genes in these cells. Consistent results showed that both p53-PUMA/NOXA/Bcl2-Bax and p53-p21 pathways contribute to the CDglyTK induced tumor cell suppression. Our work for the first time addressed the role of p53 related genes in the CDglyTK/prodrug system.

  20. From Ugly Duckling to Swan: Unexpected Identification from Cell-SELEX of an Anti-Annexin A2 Aptamer Targeting Tumors

    Science.gov (United States)

    Cibiel, Agnes; Nguyen Quang, Nam; Gombert, Karine; Thézé, Benoit; Garofalakis, Anikitos; Ducongé, Frédéric

    2014-01-01

    Background Cell-SELEX is now widely used for the selection of aptamers against cell surface biomarkers. However, despite negative selection steps using mock cells, this method sometimes results in aptamers against undesirable targets that are expressed both on mock and targeted cells. Studying these junk aptamers might be useful for further applications than those originally envisaged. Methodology/Principal Findings Cell-SELEX was performed to identify aptamers against CHO-K1 cells expressing human Endothelin type B receptor (ETBR). CHO-K1 cells were used for negative selection of aptamers. Several aptamers were identified but no one could discriminate between both cell lines. We decided to study one of these aptamers, named ACE4, and we identified that it binds to the Annexin A2, a protein overexpressed in many cancers. Radioactive binding assays and flow cytometry demonstrated that the aptamer was able to bind several cancer cell lines from different origins, particularly the MCF-7 cells. Fluorescence microscopy revealed it could be completely internalized in cells in 2 hours. Finally, the tumor targeting of the aptamer was evaluated in vivo in nude mice xenograft with MCF-7 cells using fluorescence diffuse optical tomography (fDOT) imaging. Three hours after intravenous injection, the aptamer demonstrated a significantly higher uptake in the tumor compared to a scramble sequence. Conclusions/Significance Although aptamers could be selected during cell-SELEX against other targets than those initially intended, they represent a potential source of ligands for basic research, diagnoses and therapy. Here, studying such aptamers, we identify one with high affinity for Annexin A2 that could be a promising tool for biomedical application. PMID:24489826

  1. From ugly duckling to swan: unexpected identification from cell-SELEX of an anti-Annexin A2 aptamer targeting tumors.

    Directory of Open Access Journals (Sweden)

    Agnes Cibiel

    Full Text Available BACKGROUND: Cell-SELEX is now widely used for the selection of aptamers against cell surface biomarkers. However, despite negative selection steps using mock cells, this method sometimes results in aptamers against undesirable targets that are expressed both on mock and targeted cells. Studying these junk aptamers might be useful for further applications than those originally envisaged. METHODOLOGY/PRINCIPAL FINDINGS: Cell-SELEX was performed to identify aptamers against CHO-K1 cells expressing human Endothelin type B receptor (ETBR. CHO-K1 cells were used for negative selection of aptamers. Several aptamers were identified but no one could discriminate between both cell lines. We decided to study one of these aptamers, named ACE4, and we identified that it binds to the Annexin A2, a protein overexpressed in many cancers. Radioactive binding assays and flow cytometry demonstrated that the aptamer was able to bind several cancer cell lines from different origins, particularly the MCF-7 cells. Fluorescence microscopy revealed it could be completely internalized in cells in 2 hours. Finally, the tumor targeting of the aptamer was evaluated in vivo in nude mice xenograft with MCF-7 cells using fluorescence diffuse optical tomography (fDOT imaging. Three hours after intravenous injection, the aptamer demonstrated a significantly higher uptake in the tumor compared to a scramble sequence. CONCLUSIONS/SIGNIFICANCE: Although aptamers could be selected during cell-SELEX against other targets than those initially intended, they represent a potential source of ligands for basic research, diagnoses and therapy. Here, studying such aptamers, we identify one with high affinity for Annexin A2 that could be a promising tool for biomedical application.

  2. Vaccination with a recombinant protein encoding the tumor-specific antigen NY-ESO-1 elicits an A2/157-165-specific CTL repertoire structurally distinct and of reduced tumor reactivity than that elicited by spontaneous immune responses to NY-ESO-1-expressing Tumors.

    Science.gov (United States)

    Bioley, Gilles; Guillaume, Philippe; Luescher, Immanuel; Bhardwaj, Nina; Mears, Gregory; Old, Lloyd; Valmori, Danila; Ayyoub, Maha

    2009-01-01

    In a recent vaccination trial assessing the immunogenicity of an NY-ESO-1 (ESO) recombinant protein administered with Montanide and CpG, we have obtained evidence that this vaccine induces specific cytolytic T lymphocytes (CTL) in half of the patients. Most vaccine-induced CTLs were directed against epitopes located in the central part of the protein, between amino acids 81 and 110. This immunodominant region, however, is distinct from another ESO CTL region, 157-165, that is a frequent target of spontaneous CTL responses in A2+ patients bearing ESO tumors. In this study, we have investigated the CTL responses to ESO 157-165 in A2+ patients vaccinated with the recombinant protein. Our data indicate that after vaccination with the protein, CTL responses to ESO 157-165 are induced in some, but not all, A2+ patients. ESO 157-165-specific CTLs induced by vaccination with the ESO protein were functionally heterogeneous in terms of tumor recognition and often displayed decreased tumor reactivity as compared with ESO 157-165-specific CTLs isolated from patients with spontaneous immune responses to ESO. Remarkably, protein-induced CTLs used T-cell receptors similar to those previously isolated from patients vaccinated with synthetic ESO peptides (Vbeta4.1) and distinct from those used by highly tumor-reactive CTLs isolated from patients with spontaneous immune responses (Vbeta1.1, Vbeta8.1, and Vbeta13.1). Together, these results demonstrate that vaccination with the ESO protein elicits a repertoire of ESO 157-165-specific CTLs bearing T-cell receptors that are structurally distinct from those of CTLs found in spontaneous immune responses to the antigen and that are heterogeneous in terms of tumor reactivity, being often poorly tumor reactive.

  3. Novel nano-sized MR contrast agent mediates strong tumor contrast enhancement in an oncogene-driven breast cancer model.

    Directory of Open Access Journals (Sweden)

    Per-Olof Eriksson

    Full Text Available The current study was carried out to test the potential of a new nanomaterial (Spago Pix as a macromolecular magnetic MR contrast agent for tumor detection and to verify the presence of nanomaterial in tumor tissue. Spago Pix, synthesized by Spago Nanomedical AB, is a nanomaterial with a globular shape, an average hydrodynamic diameter of 5 nm, and a relaxivity (r1 of approximately 30 (mM Mn-1 s-1 (60 MHz. The material consists of an organophosphosilane hydrogel with strongly chelated manganese (II ions and a covalently attached PEG surface layer. In vivo MRI of the MMTV-PyMT breast cancer model was performed on a 3 T clinical scanner. Tissues were thereafter analyzed for manganese and silicon content using inductively coupled plasma-atomic emission spectroscopy (ICP-AES. The presence of nanomaterial in tumor and muscle tissue was assessed using an anti-PEG monoclonal antibody. MR imaging of tumor-bearing mice (n = 7 showed a contrast enhancement factor of 1.8 (tumor versus muscle at 30 minutes post-administration. Contrast was retained and further increased 2-4 hours after administration. ICP-AES and immunohistochemistry confirmed selective accumulation of nanomaterial in tumor tissue. A blood pharmacokinetics analysis showed that the concentration of Spago Pix gradually decreased over the first hour, which was in good agreement with the time frame in which the accumulation in tumor occurred. In summary, we demonstrate that Spago Pix selectively enhances MR tumor contrast in a clinically relevant animal model. Based on the generally higher vascular leakiness in malignant compared to benign tissue lesions, Spago Pix has the potential to significantly improve cancer diagnosis and characterization by MRI.

  4. Ibrutinib interferes with the cell-mediated anti-tumor activities of therapeutic CD20 antibodies: implications for combination therapy

    DEFF Research Database (Denmark)

    Da Roit, F.; Engelberts, P. J.; Taylor, R. P.

    2015-01-01

    -treatment with ibrutinib did not inhibit complement activation or complement-mediated lysis. In contrast, ibrutinib strongly inhibited all cell-mediated mechanisms induced by anti-CD20 antibodies rituximab, ofatumumab or obinutuzumab, either in purified systems or whole blood assays. Activation of natural killer cells...

  5. CHIP/Stub1 functions as a tumor suppressor and represses NF-κB-mediated signaling in colorectal cancer.

    Science.gov (United States)

    Wang, Yangmeng; Ren, Fangli; Wang, Yinyin; Feng, Yarui; Wang, Dianjun; Jia, Baoqing; Qiu, Ying; Wang, Shiyan; Yu, Jun; Sung, Joseph Jy; Xu, Jiake; Zeps, Nikolajs; Chang, Zhijie

    2014-05-01

    The carboxyl terminus of Hsc70-interacting protein (CHIP, also named Stub1), a U-box containing E3 ubiquitin ligase, is involved in degradation of certain oncogenic proteins. Recent studies indicated that CHIP suppresses tumor progression in human cancers by targeting Src-3, hypoxia inducible factor 1α, NF-κB, ErbB2 and c-Myc. Here, we report that CHIP was downregulated, predominantly, in the late stages of human colorectal cancer (CRC), and that the CHIP promoter was hypermethylated in CRC specimens. Overexpression of CHIP in HCT-116 cells resulted in impaired tumor growth in nude mice and decreased abilities of tumor cell migration and invasion. Conversely, depletion of CHIP in HCT-116 cells promoted tumor growth and increased tumor cell migration and invasion. CHIP was further found to negatively regulate NF-κB signaling in HCT-116 cells by promoting ubiquitination and degradation of p65, a subunit of the NF-κB complex. The suppressive effect of CHIP led to decreased expression of NF-κB-targeted oncogenes including Cyclin D1, c-Myc, MMP-2, VEGF and IL-8. We proposed that CHIP inhibits the malignancy of CRC cells, possibly through targeting NF-κB signaling. This study provides functional evidence for CHIP as a potential tumor suppressor in CRC, and CHIP expression may be a marker for stages of CRC.

  6. Tumor necrosis factor alpha modulates the dynamics of the plasminogen-mediated early interaction between Bifidobacterium animalis subsp. lactis and human enterocytes.

    Science.gov (United States)

    Centanni, Manuela; Bergmann, Simone; Turroni, Silvia; Hammerschmidt, Sven; Chhatwal, Gursharan Singh; Brigidi, Patrizia; Candela, Marco

    2012-04-01

    The capacity to intervene with the host plasminogen system has recently been considered an important component in the interaction process between Bifidobacterium animalis subsp. lactis and the human host. However, its significance in the bifidobacterial microecology within the human gastrointestinal tract is still an open question. Here we demonstrate that human plasminogen favors the B. animalis subsp. lactis BI07 adhesion to HT29 cells. Prompting the HT29 cell capacity to activate plasminogen, tumor necrosis factor alpha (TNF-α) modulated the plasminogen-mediated bacterium-enterocyte interaction, reducing the bacterial adhesion to the enterocytes and enhancing migration to the luminal compartment.

  7. The S100A10 subunit of the annexin A2 heterotetramer facilitates L2-mediated human papillomavirus infection.

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    Andrew W Woodham

    Full Text Available Mucosotropic, high-risk human papillomaviruses (HPV are sexually transmitted viruses that are causally associated with the development of cervical cancer. The most common high-risk genotype, HPV16, is an obligatory intracellular virus that must gain entry into host epithelial cells and deliver its double stranded DNA to the nucleus. HPV capsid proteins play a vital role in these steps. Despite the critical nature of these capsid protein-host cell interactions, the precise cellular components necessary for HPV16 infection of epithelial cells remains unknown. Several neutralizing epitopes have been identified for the HPV16 L2 minor capsid protein that can inhibit infection after initial attachment of the virus to the cell surface, which suggests an L2-specific secondary receptor or cofactor is required for infection, but so far no specific L2-receptor has been identified. Here, we demonstrate that the annexin A2 heterotetramer (A2t contributes to HPV16 infection and co-immunoprecipitates with HPV16 particles on the surface of epithelial cells in an L2-dependent manner. Inhibiting A2t with an endogenous annexin A2 ligand, secretory leukocyte protease inhibitor (SLPI, or with an annexin A2 antibody significantly reduces HPV16 infection. With electron paramagnetic resonance, we demonstrate that a previously identified neutralizing epitope of L2 (aa 108-120 specifically interacts with the S100A10 subunit of A2t. Additionally, mutation of this L2 region significantly reduces binding to A2t and HPV16 pseudovirus infection. Furthermore, downregulation of A2t with shRNA significantly decreases capsid internalization and infection by HPV16. Taken together, these findings indicate that A2t contributes to HPV16 internalization and infection of epithelial cells and this interaction is dependent on the presence of the L2 minor capsid protein.

  8. miRNA-200c mediates mono-butyl phthalate-disrupted steroidogenesis by targeting vimentin in Leydig tumor cells and murine adrenocortical tumor cells.

    Science.gov (United States)

    Lu, Hongchao; Zhang, Chang; Hu, Yanhui; Qin, Heng; Gu, Aihua; Li, Yuan; Zhang, Lulu; Li, Zhong; Wang, Yubang

    2016-01-22

    The reproductive toxicity of plasticizer di-n-butyl phthalate (DBP) and its active metabolite monobutyl phthalate (MBP) has been demonstrated in rodents. The objective of this study was to explore roles of vimentin and miRNA-200c in steroidogenesis interfered by MBP. Mouse Leydig tumor cells (MLTC-1) and murine adrenocortical tumor cells (Y1) were employed and exposed to various levels of MBP (10(-7), 10(-6), 10(-5) and 10(-4)M). Steroid hormone production was increased significantly when MLTC-1 and Y1 cells were exposed to MBP at 10(-7)M. Additionally, vimentin and steroidogenic acute regulatory protein (StAR) expressions were upregulated at the same dose. It was found that MBP increased the steroidogenesis by facilitating the cholesterol transfer process by vimentin. In contrast, miRNA-200c expression was depressed at doses of MBP (10(-7)M) in both cells. Moreover, vimentin expression and progesterone production were increased in both MLTC-1 and Y1 cells after miRNA-200c expression was artificially inhibited. These results strongly suggested that MBP raised steroid hormone synthesis via upregulated vimentin by miRNA-200c.

  9. Geldanamycin mediates the apoptosis of gastric carcinoma cells through inhibition of EphA2 protein expression.

    Science.gov (United States)

    Wang, Da-Hu; Zhang, Yu-Jun; Zhang, San-Bing; Liu, Hui; Liu, Liang; Liu, Feng-Ling; Zuo, Jing

    2014-12-01

    The aim of the present study was to investigate the role of EphA2 in the carcinogenesis and progression of gastric carcinoma. Moreover, we aimed to determine the effect of geldanamycin (GA), an inhibitor of Hsp90, on the proliferation and apoptosis of human gastric carcinoma cells. Gastric carcinoma tissues, paired adjacent mucosa and paired normal mucosa were obtained from resected surgical specimens of gastric carcinoma, and EphA2 mRNA and protein levels were assessed by RT-PCR, immunohistochemistry and western blot analysis. FCM was used to detect cell cycle distribution and apoptosis. MGC803 cell proliferation and apoptosis were assessed by MTT and FCM, respectively. We found that EphA2 protein was increased in the carcinogenesis of gastric epithelial cells. Proliferation index (PI) was significantly upregulated following an increase in EphA2 expression in gastric carcinoma compared with dysplasia and normal samples, and was notably correlated with grade and lymph node metastasis. Knockdown of EphA2 increased the apoptosis rate and decreased the PI of MGC803 cells, which overexpressed the EphA2 protein. GA inhibited the cell proliferation of MGC803 cells in a dose- and time-dependent manner and induced cell apoptosis. In addition, GA decreased the EphA2 protein expression in MGC803 cells. Overexpression of EphA2 inhibited cell growth, blocked cells in the G0/G1 stage and increased cell apoptosis induced by GA in MGC803 cells. However, knockdown of EphA2 in MGC803 cells increased the apoptosis ratio induced by GA. In conclusion, EphA2 overexpression is an important characteristic in the carcinogenesis of gastric epithelial cells, followed by an increase in apoptosis and cell cycle arrest. Knockdown of EphA2 blocked MGC803 cell proliferation and induced cell apoptosis. In conclusion GA inhibits MGC803 cell proliferation and induces cell apoptosis by upregulating expression of EphA2.

  10. Interplay among Drosophila transcription factors Ets21c, Fos and Ftz-F1 drives JNK-mediated tumor malignancy

    Directory of Open Access Journals (Sweden)

    Eva Külshammer

    2015-10-01

    Full Text Available Cancer initiation and maintenance of the transformed cell state depend on altered cellular signaling and aberrant activities of transcription factors (TFs that drive pathological gene expression in response to cooperating genetic lesions. Deciphering the roles of interacting TFs is therefore central to understanding carcinogenesis and for designing cancer therapies. Here, we use an unbiased genomic approach to define a TF network that triggers an abnormal gene expression program promoting malignancy of clonal tumors, generated in Drosophila imaginal disc epithelium by gain of oncogenic Ras (RasV12 and loss of the tumor suppressor Scribble (scrib1. We show that malignant transformation of the rasV12scrib1 tumors requires TFs of distinct families, namely the bZIP protein Fos, the ETS-domain factor Ets21c and the nuclear receptor Ftz-F1, all acting downstream of Jun-N-terminal kinase (JNK. Depleting any of the three TFs improves viability of tumor-bearing larvae, and this positive effect can be enhanced further by their combined removal. Although both Fos and Ftz-F1 synergistically contribute to rasV12scrib1 tumor invasiveness, only Fos is required for JNK-induced differentiation defects and Matrix metalloprotease (MMP1 upregulation. In contrast, the Fos-dimerizing partner Jun is dispensable for JNK to exert its effects in rasV12scrib1 tumors. Interestingly, Ets21c and Ftz-F1 are transcriptionally induced in these tumors in a JNK- and Fos-dependent manner, thereby demonstrating a hierarchy within the tripartite TF network, with Fos acting as the most upstream JNK effector. Of the three TFs, only Ets21c can efficiently substitute for loss of polarity and cooperate with RasV12 in inducing malignant clones that, like rasV12scrib1 tumors, invade other tissues and overexpress MMP1 and the Drosophila insulin-like peptide 8 (Dilp8. While rasV12ets21c tumors require JNK for invasiveness, the JNK activity is dispensable for their growth. In conclusion, our

  11. Interplay among Drosophila transcription factors Ets21c, Fos and Ftz-F1 drives JNK-mediated tumor malignancy.

    Science.gov (United States)

    Külshammer, Eva; Mundorf, Juliane; Kilinc, Merve; Frommolt, Peter; Wagle, Prerana; Uhlirova, Mirka

    2015-10-01

    Cancer initiation and maintenance of the transformed cell state depend on altered cellular signaling and aberrant activities of transcription factors (TFs) that drive pathological gene expression in response to cooperating genetic lesions. Deciphering the roles of interacting TFs is therefore central to understanding carcinogenesis and for designing cancer therapies. Here, we use an unbiased genomic approach to define a TF network that triggers an abnormal gene expression program promoting malignancy of clonal tumors, generated in Drosophila imaginal disc epithelium by gain of oncogenic Ras (Ras(V12)) and loss of the tumor suppressor Scribble (scrib(1)). We show that malignant transformation of the ras(V12)scrib(1) tumors requires TFs of distinct families, namely the bZIP protein Fos, the ETS-domain factor Ets21c and the nuclear receptor Ftz-F1, all acting downstream of Jun-N-terminal kinase (JNK). Depleting any of the three TFs improves viability of tumor-bearing larvae, and this positive effect can be enhanced further by their combined removal. Although both Fos and Ftz-F1 synergistically contribute to ras(V12)scrib(1) tumor invasiveness, only Fos is required for JNK-induced differentiation defects and Matrix metalloprotease (MMP1) upregulation. In contrast, the Fos-dimerizing partner Jun is dispensable for JNK to exert its effects in ras(V12)scrib(1) tumors. Interestingly, Ets21c and Ftz-F1 are transcriptionally induced in these tumors in a JNK- and Fos-dependent manner, thereby demonstrating a hierarchy within the tripartite TF network, with Fos acting as the most upstream JNK effector. Of the three TFs, only Ets21c can efficiently substitute for loss of polarity and cooperate with Ras(V12) in inducing malignant clones that, like ras(V12)scrib(1) tumors, invade other tissues and overexpress MMP1 and the Drosophila insulin-like peptide 8 (Dilp8). While ras(V12)ets21c tumors require JNK for invasiveness, the JNK activity is dispensable for their growth. In

  12. CCL5/CCR5 axis induces vascular endothelial growth factor-mediated tumor angiogenesis in human osteosarcoma microenvironment.

    Science.gov (United States)

    Wang, Shih-Wei; Liu, Shih-Chia; Sun, Hui-Lung; Huang, Te-Yang; Chan, Chia-Han; Yang, Chen-Yu; Yeh, Hung-I; Huang, Yuan-Li; Chou, Wen-Yi; Lin, Yu-Min; Tang, Chih-Hsin

    2015-01-01

    Chemokines modulate angiogenesis and metastasis that dictate cancer development in tumor microenvironment. Osteosarcoma is the most frequent bone tumor and is characterized by a high metastatic potential. Chemokine CCL5 (previously called RANTES) has been reported to facilitate tumor progression and metastasis. However, the crosstalk between chemokine CCL5 and vascular endothelial growth factor (VEGF) as well as tumor angiogenesis in human osteosarcoma microenvironment has not been well explored. In this study, we found that CCL5 increased VEGF expression and production in human osteosarcoma cells. The conditioned medium (CM) from CCL5-treated osteosarcoma cells significantly induced tube formation and migration of human endothelial progenitor cells. Pretreatment of cells with CCR5 antibody or transfection with CCR5 specific siRNA blocked CCL5-induced VEGF expression and angiogenesis. CCL5/CCR5 axis demonstrably activated protein kinase Cδ (PKCδ), c-Src and hypoxia-inducible factor-1 alpha (HIF-1α) signaling cascades to induce VEGF-dependent angiogenesis. Furthermore, knockdown of CCL5 suppressed VEGF expression and attenuated osteosarcoma CM-induced angiogenesis in vitro and in vivo. CCL5 knockdown dramatically abolished tumor growth and angiogenesis in the osteosarcoma xenograft animal model. Importantly, we demonstrated that the expression of CCL5 and VEGF were correlated with tumor stage according the immunohistochemistry analysis of human osteosarcoma tissues. Taken together, our findings provide evidence that CCL5/CCR5 axis promotes VEGF-dependent tumor angiogenesis in human osteosarcoma microenvironment through PKCδ/c-Src/HIF-1α signaling pathway. CCL5 may represent a potential therapeutic target against human osteosarcoma.

  13. Methyl 6-Amino-6-deoxy-d-pyranoside-Conjugated Platinum(II) Complexes for Glucose Transporter (GLUT)-Mediated Tumor Targeting: Synthesis, Cytotoxicity, and Cellular Uptake Mechanism.

    Science.gov (United States)

    Li, Taoli; Gao, Xiangqian; Yang, Liu; Shi, Yunli; Gao, Qingzhi

    2016-05-19

    Methyl 6-aminodeoxy-d-pyranoside-derived platinum(II) glycoconjugates were designed and synthesized based on the clinical drug oxaliplatin for glucose transporter (GLUT)-mediated tumor targeting. In addition to a substantial improvement in water solubility, the conjugates exhibited cytotoxicity similar to or higher than that of oxaliplatin in six different human cancer cell lines. GLUT-mediated transport of the complexes was investigated with a cell-based fluorescence competition assay and GLUT-inhibitor-mediated cytotoxicity analysis in a GLUT-overexpressing human colorectal adenocarcinoma (HT29) cell line. The antitumor effect of the aminodeoxypyranoside-conjugated platinum(II) complexes was found to depend significantly on the GLUT inhibitor, and the cellular uptake of the molecules was regulated by GLUT-mediated transport. The results from this study demonstrate the potential advantages of aminodeoxypyranosides as sugar motifs for glycoconjugation for Warburg-effect-targeted drug design. These fundamental results also support the potential of aminodeoxypyranoside-conjugated platinum(II) complexes as lead compounds for further preclinical evaluation.

  14. The eukaryotic translation elongation factor eEF1A2 induces neoplastic properties and mediates tumorigenic effects of ZNF217 in precursor cells of human ovarian carcinomas

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Yu; Wong, Nicholas; Guan, Yinghui; Salamanca, Clara M.; Cheng, Jung Chien; Lee, Jonathan M.; Gray, Joe W.; Auersperg, Nelly

    2008-04-25

    Ovarian epithelial carcinomas (OEC) frequently exhibit amplifications at the 20q13 locus which is the site of several oncogenes, including the eukaryotic elongation factor EEF1A2 and the transcription factor ZNF217. We reported previously that overexpressed ZNF217 induces neoplastic characteristics in precursor cells of OEC. Unexpectedly, ZNF217, which is a transcriptional repressor, enhanced expression of eEF1A2. In this study, array comparative genomic hybridization, single nucleotide polymorphism and Affymetrix analysis of ZNF217-overexpressing cell lines confirmed consistently increased expression of eEF1A2 but not of other oncogenes, and revealed early changes in EEF1A2 gene copy numbers and increased expression at crisis during immortalization. We defined the influence of eEF1A2 overexpression on immortalized ovarian surface epithelial cells, and investigated interrelationships between effects of ZNF217 and eEF1A2 on cellular phenotypes. Lentivirally induced eEF1A2 overexpression caused delayed crisis, apoptosis resistance and increases in serum-independence, saturation densities, and anchorage independence. siRNA to eEF1A2 reversed apoptosis resistance and reduced anchorage independence in eEF1A2-overexpressing lines. Remarkably, siRNA to eEF1A2 was equally efficient in inhibiting both anchorage independence and resistance to apoptosis conferred by ZNF217 overexpression. Our data define neoplastic properties that are caused by eEF1A2 in nontumorigenic ovarian cancer precursor cells, and suggest that eEF1A2 plays a role in mediating ZNF217-induced neoplastic progression.

  15. A Copper-Mediated Disulfiram-Loaded pH-Triggered PEG-Shedding TAT Peptide-Modified Lipid Nanocapsules for Use in Tumor Therapy.

    Science.gov (United States)

    Zhang, Ling; Tian, Bin; Li, Yi; Lei, Tian; Meng, Jia; Yang, Liu; Zhang, Yan; Chen, Fen; Zhang, Haotian; Xu, Hui; Zhang, Yu; Tang, Xing

    2015-11-18

    Disulfiram, which exhibits marked tumor inhibition mediated by copper, was encapsulated in lipid nanocapsules modified with TAT peptide (TATp) and pH-triggered sheddable PEG to target cancer cells on the basis of tumor environmental specificity. PEG-shedding lipid nanocapsules (S-LNCs) were fabricated from LNCs by decorating short PEG chains with TATp (HS-PEG(1k)-TATp) to form TATp-LNCs and then covered by pH-sensitive graft copolymers of long PEG chains (PGA-g-PEG(2k)). The DSF-S-LNCs had sizes in the range of 60-90 nm and were stable in the presence of 50% plasma. DSF-S-LNCs exhibited higher intracellular uptake and antitumor activity at pH 6.5 than at pH 7.4. The preincubation of Cu showed that the DSF cytotoxicity was based on the accumulation of Cu in Hep G2 cells. Pharmacokinetic studies showed the markedly improved pharmacokinetic profiles of DSF-S-LNCs (AUC= 3921.391 μg/L·h, t(1/2z) = 1.294 h) compared with free DSF (AUC = 907.724 μg/L·h, t(1/2z) = 0.252 h). The in vivo distribution of S-LNCs was investigated using Cy5.5 as a fluorescent probe. In tumor-bearing mice, the delivery efficiency of S-LNCs was found to be 496.5% higher than that of free Cy5.5 and 74.5% higher than that of LNCs in tumors. In conclusion, DSF-S-LNCs increased both the stability and tumor internalization and further increased the cytotoxicity because of the higher copper content.

  16. The in vivo therapeutic efficacy of the oncolytic adenovirus Delta24-RGD is mediated by tumor-specific immunity.

    Directory of Open Access Journals (Sweden)

    Anne Kleijn

    Full Text Available The oncolytic adenovirus Delta24-RGD represents a new promising therapeutic agent for patients with a malignant glioma and is currently under investigation in clinical phase I/II trials. Earlier preclinical studies showed that Delta24-RGD is able to effectively lyse tumor cells, yielding promising results in various immune-deficient glioma models. However, the role of the immune response in oncolytic adenovirus therapy for glioma has never been explored. To this end, we assessed Delta24-RGD treatment in an immune-competent orthotopic mouse model for glioma and evaluated immune responses against tumor and virus. Delta24-RGD treatment led to long-term survival in 50% of mice and this effect was completely lost upon administration of the immunosuppressive agent dexamethasone. Delta24-RGD enhanced intra-tumoral infiltration of F4/80+ macrophages, CD4+ and CD8+ T-cells, and increased the local production of pro-inflammatory cytokines and chemokines. In treated mice, T cell responses were directed to the virus as well as to the tumor cells, which was reflected in the presence of protective immunological memory in mice that underwent tumor rechallenge. Together, these data provide evidence that the immune system plays a vital role in the therapeutic efficacy of oncolytic adenovirus therapy of glioma, and may provide angles to future improvements on Delta24-RGD therapy.

  17. Interleukin-1beta but not tumor necrosis factor-alpha potentiates neuronal damage by quinolinic acid: protection by an adenosine A2A receptor antagonist.

    Science.gov (United States)

    Stone, Trevor W; Behan, Wilhelmina M H

    2007-04-01

    Quinolinic acid is an agonist at glutamate receptors sensitive to N-methyl-D-aspartate (NMDA). It has been implicated in neural dysfunction associated with infections, trauma, and ischemia, although its neurotoxic potency is relatively low. This study was designed to examine the effects of a combination of quinolinic acid and the proinflammatory cytokines interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha). Compounds were administered to the hippocampus of anesthetized male rats, animals being allowed to recover for 7 days before histological analysis of the hippocampus for neuronal damage estimated by counting of intact, healthy neurons. A low dose of quinolinic acid or IL-1beta produced no damage by itself, but the two together induced a significant loss of pyramidal neurons in the hippocampus. Higher doses produced almost total loss of pyramidal cells. Intrahippocampal TNF-alpha produced no effect alone but significantly reduced the neuronal loss produced by quinolinic acid. The adenosine A(2A) receptor antagonist ZM241385 reduced neuronal loss produced by the combinations of quinolinic acid and IL-1beta. The results suggest that simultaneous quinolinic acid and IL-1beta, both being induced by cerebral infection or injury, are synergistic in the production of neuronal damage and could together contribute substantially to traumatic, infective, or ischemic cerebral damage. Antagonism of adenosine A(2A) receptors protects neurons against the combination of quinolinic acid and IL-1beta.

  18. The effects of adenosine A2B receptor inhibition on VEGF and nitric oxide axis-mediated renal function in diabetic nephropathy.

    Science.gov (United States)

    Patel, Leena; Thaker, Aswin

    2014-07-01

    Diabetic nephropathy (DN) is the most common cause of end-stage renal disease worldwide. The pathophysiologic mechanisms of diabetic nephropathy are incompletely understood but include overproduction of various growth factors and cytokines. Upregulation of vascular endothelial growth factor (VEGF) is a pathogenic event occurring in most forms of podocytopathy; however, the mechanisms that regulate this growth factor induction are not clearly identified. A2B receptors have been found to regulate VEGF expression under hypoxic environment in different tissues. One proposed hypothesis in mediating diabetic nephropathy is the modulation of VEGF-NO balance in renal tissue. We determined the role of adenosine A2B receptor in mediating VEGF overproduction and nitrite in diabetic nephropathy. The renal content of A2B receptors and VEGF was increased after 8 weeks of diabetes induction. The renal and plasma nitrite levels were also reduced in these animals. In vivo administration of A2B adenosine receptor antagonist (MRS1754) inhibited the renal over expression of VEGF and adverse renal function parameters. The antagonist administration also improved the kidney tissue nitrite levels. In conclusion, we demonstrated that VEGF induction via adenosine signaling might be the critical event in regulating VEGF-NO axis in diabetic nephropathy.

  19. Aptamer-Mediated Codelivery of Doxorubicin and NF-κB Decoy Enhances Chemosensitivity of Pancreatic Tumor Cells

    Directory of Open Access Journals (Sweden)

    David Porciani

    2015-01-01

    Full Text Available Aptamers able to bind efficiently cell-surface receptors differentially expressed in tumor and in healthy cells are emerging as powerful tools to perform targeted anticancer therapy. Here, we present a novel oligonucleotide chimera, composed by an RNA aptamer and a DNA decoy. Our assembly is able to (i target tumor cells via an antitransferrin receptor RNA aptamer and (ii perform selective codelivery of a chemotherapeutic drug (Doxorubicin and of an inhibitor of a cell-survival factor, the nuclear factor κB decoy oligonucleotide. Both payloads are released under conditions found in endolysosomal compartments (low pH and reductive environment. Targeting and cytotoxicity of the oligonucleotidic chimera were assessed by confocal microscopy, cell viability, and Western blot analysis. These data indicated that the nuclear factor κB decoy does inhibit nuclear factor κB activity and ultimately leads to an increased therapeutic efficacy of Doxorubicin selectively in tumor cells.

  20. Activation-induced cytidine deaminase is dispensable for virus-mediated liver and skin tumor development in mouse models.

    Science.gov (United States)

    Nguyen, Tung; Xu, Jianliang; Chikuma, Shunsuke; Hiai, Hiroshi; Kinoshita, Kazuo; Moriya, Kyoji; Koike, Kazuhiko; Marcuzzi, Gian Paolo; Pfister, Herbert; Honjo, Tasuku; Kobayashi, Maki

    2014-07-01

    Activation-induced cytidine deaminase (AID) not only promotes immune diversity by initiating somatic hypermutation and class switch recombination in immunoglobulin genes but also provokes genomic instability by introducing translocations and mutations into non-immunoglobulin genes. To test whether AID is essential for virus-induced tumor development, we used two transgenic tumor models: mice expressing hepatitis C virus (HCV) core proteins (HCV-Tg), driven by the hepatitis B virus promoter, and mice expressing human papillomavirus type 8 proteins (HPV8-Tg), driven by the Keratin 14 promoter. Both strains were analyzed in the absence and presence of AID by crossing each with AID (-/-) mice. There was no difference in the liver tumor frequency between the HCV-Tg/AID (+/+) and HCV-Tg/AID (-/-) mice at 20 months of age although the AID (+/+) mice showed more severe histological findings and increased cytokine expression. Furthermore, a low level of AID transcript was detected in the HCV-Tg/AID (+/+) liver tissue that was not derived from hepatocytes themselves but from intra-hepatic immune cells. Although AID may not be the direct cause of HCV-induced oncogenesis, AID expressed in B cells, not in hepatocytes, may prolong steatosis and cause increased lymphocyte infiltration into HCV core protein-induced liver lesions. Similarly, there was no difference in the time course of skin tumor development between the HPV8-Tg/AID (-/-) and HPV8-Tg/AID (+/+) groups. In conclusion, AID does not appear to be required for tumor development in the two virus-induced tumor mouse models tested although AID expressed in infiltrating B cells may promote inflammatory reactions in HCV core protein-induced liver pathogenesis.

  1. Proapoptotic protein Smac mediates apoptosis in cisplatin-resistant ovarian cancer cells when treated with the anti-tumor agent AT101.

    Science.gov (United States)

    Hu, Wenbin; Wang, Fang; Tang, Jingsheng; Liu, Xinyu; Yuan, Zhu; Nie, Chunlai; Wei, Yuquan

    2012-01-02

    Chemoresistance of ovarian cancer has been previously attributed to the expression and activation of Bcl-2 family proteins. BH3-mimetic molecules possessing potential anticancer activity are able to inhibit antiapoptotic Bcl-2 family proteins. AT101 (R-(-)-gossypol), a natural BH3-mimetic molecule, has shown anti-tumor activity as a single agent and in combination with standard anticancer therapies in a variety of tumor models. Here, we report the effect of AT101 on apoptosis in cisplatin-resistant ovarian cancer cells and identify the major molecular events that determine sensitivity. AT101 induced cell apoptosis by activating Bax through a conformational change, translocation, and oligomerization. The inhibition of Bax expression only partially prevented caspase-3 cleavage. However, the gene silencing of Bax had no effect on mitochondrial Smac release. Further experiments demonstrated that Smac reduction inhibited caspase-3 activation and attenuated cell apoptosis. More importantly, the inhibition of Smac or overexpression of XIAP attenuated Bax activation in ovarian cells. Furthermore, our data indicate that the Akt-p53 pathway is involved in the regulation of Smac release. Taken together, our data demonstrate the role of Smac and the molecular mechanisms of AT101-induced apoptosis of chemoresistant ovarian cancer cells. Our findings suggest that AT101 not only triggers Bax activation but also induces mitochondrial Smac release. Activated Smac can enhance Bax-mediated cellular apoptosis. Therefore, Smac mediates Bax activation to determine the threshold for overcoming cisplatin resistance in ovarian cancer cells.

  2. Tumor Suppressor Pten Inhibits Nuclear Accumulation of β-Catenin and T Cell/Lymphoid Enhancer Factor 1–Mediated Transcriptional Activation

    Science.gov (United States)

    Persad, Sujata; A.Troussard, Armelle; McPhee, Timothy R.; Mulholland, David J.; Dedhar, Shoukat

    2001-01-01

    β-Catenin is a protein that plays a role in intercellular adhesion as well as in the regulation of gene expression. The latter role of β-catenin is associated with its oncogenic properties due to the loss of expression or inactivation of the tumor suppressor adenomatous polyposis coli (APC) or mutations in β-catenin itself. We now demonstrate that another tumor suppressor, PTEN, is also involved in the regulation of nuclear β-catenin accumulation and T cell factor (TCF) transcriptional activation in an APC-independent manner. We show that nuclear β-catenin expression is constitutively elevated in PTEN null cells and this elevated expression is reduced upon reexpression of PTEN. TCF promoter/luciferase reporter assays and gel mobility shift analysis demonstrate that PTEN also suppresses TCF transcriptional activity. Furthermore, the constitutively elevated expression of cyclin D1, a β-catenin/TCF–regulated gene, is also suppressed upon reexpression of PTEN. Mechanistically, PTEN increases the phosphorylation of β-catenin and enhances its rate of degradation. We define a pathway that involves mainly integrin-linked kinase and glycogen synthase kinase 3 in the PTEN-dependent regulation of β-catenin stability, nuclear β-catenin expression, and transcriptional activity. Our data indicate that β-catenin/TCF–mediated gene transcription is regulated by PTEN, and this may represent a key mechanism by which PTEN suppresses tumor progression. PMID:11402061

  3. Hemagglutinin protease secreted by V. cholerae induced apoptosis in breast cancer cells by ROS mediated intrinsic pathway and regresses tumor growth in mice model.

    Science.gov (United States)

    Ray, Tanusree; Chakrabarti, Monoj Kumar; Pal, Amit

    2016-02-01

    Conventional anticancer therapies are effective but have side effects, so alternative targets are being developed. Bacterial toxins that can kill cells or alter the cellular processes like proliferation, apoptosis and differentiation have been reported for cancer treatment. In this study we have shown antitumor activity of hemagglutinin protease (HAP) secreted by Vibrio cholerae. One µg of HAP showed potent antitumor activity when injected into Ehrlich ascites carcinoma (EAC) tumors in Swiss albino mice. Weekly administration of this dose is able to significantly diminish a large tumor volume within 3 weeks and increases the survival rates of cancerous mice. HAP showed apoptotic activity on EAC and other malignant cells. Increased level of pro-apoptotic p53 with increased ratio of pro-apoptotic Bax to anti-apoptotic Bcl-2 signify that HAP induced apoptogenic signals lead to death of the tumor cells. In vivo and ex vivo studies suggest that mitochondrial dependent intrinsic pathway is responsible for this apoptosis. The level of ROS in malignant cells is reported to be higher than the normal healthy cells. HAP induces oxidative stress and increases the level of ROS in malignant cells which is significantly higher than the normal healthy cells. As a result the malignant cells cross the threshold level of ROS for cell survival faster than normal healthy cells. This mechanism causes HAP mediated apoptosis in malignant cells, but normal cells remain unaltered in the same environment. Our study suggests that HAP may be used as a new candidate drug for cancer therapy.

  4. Antibody-mediated targeting of iron oxide nanoparticles to the folate receptor alpha increases tumor cell association in vitro and in vivo.

    Science.gov (United States)

    Ndong, Christian; Toraya-Brown, Seiko; Kekalo, Katsiaryna; Baker, Ian; Gerngross, Tillman U; Fiering, Steven N; Griswold, Karl E

    2015-01-01

    Active molecular targeting has become an important aspect of nanoparticle development for oncology indications. Here, we describe molecular targeting of iron oxide nanoparticles (IONPs) to the folate receptor alpha (FOLRα) using an engineered antibody fragment (Ffab). Compared to control nanoparticles targeting the non-relevant botulinum toxin, the Ffab-IONP constructs selectively accumulated on FOLRα-overexpressing cancer cells in vitro, where they exhibited the capacity to internalize into intracellular vesicles. Similarly, Ffab-IONPs homed to FOLRα-positive tumors upon intraperitoneal administration in an orthotopic murine xenograft model of ovarian cancer, whereas negative control particles showed no detectable tumor accumulation. Interestingly, Ffab-IONPs built with custom 120 nm nanoparticles exhibited lower in vitro targeting efficiency when compared to those built with commercially sourced 180 nm nanoparticles. In vivo, however, the two Ffab-IONP platforms achieved equivalent tumor homing, although the smaller 120 nm IONPs were more prone to liver sequestration. Overall, the results show that Ffab-mediated targeting of IONPs yields specific, high-level accumulation within cancer cells, and this fact suggests that Ffab-IONPs could have future utility in ovarian cancer diagnostics and therapy.

  5. Interaction among two subpopulations of Ehrlich ascites tumor in vivo: evidence of a contact mediated immune response

    DEFF Research Database (Denmark)

    Aabo, K; Vindeløv, L L; Skovsgaard, T

    1987-01-01

    Clonal interaction among two subpopulations of Ehrlich ascites carcinoma was studied during in vivo growth in immune competent N/D mice in which the cell lines had been propagated for several years as ascites tumors. A growth inhibitory interaction by a subcutaneously slow growing subpopulation (E1...

  6. Correlation of in vivo tumor response and singlet oxygen luminescence detection in mTHPC-mediated photodynamic therapy

    Directory of Open Access Journals (Sweden)

    Brian C. Wilson

    2015-01-01

    Full Text Available Excited-state singlet oxygen (1O2, generated during photodynamic therapy (PDT, is believed to be the primary cytotoxic agent with a number of clinically approved photosensitizers. Its relative concentration in cells or tissues can be measured directly through its near-infrared (NIR luminescence emission, which has correlated well with in vitro cell and in vivo normal skin treatment responses. Here, its correlation with the response of tumor tissue in vivo is examined, using the photosensitizer meso-tetrahydroxyphenylchlorin (mTHPC in an animal model comprising luciferase- and green fluorescent protein (GFP-transduced gliosarcoma grown in a dorsal window chamber. The change in the bioluminescence signal, imaged pretreatment and at 2, 5 and 9 d post treatment, was used as a quantitative measure of the tumor response, which was classified in individual tumors as "non", "moderate" and "strong" in order to reduce the variance in the data. Plotting the bioluminescence-based response vs the 1O2 counts demonstrated clear correlation, indicating that 1O2 luminescence provides a valid dosimetric technique for PDT in tumor tissue.

  7. Ultrasound and Microbubble Mediated Doxil Delivery in a Murine Breast Cancer Model: Therapeutic Efficacy Dependence on Tumor Growth Rate

    NARCIS (Netherlands)

    Seip, R.; Leyvi, E.; Raju, B.I.; Shi, W.T.; Bohmer, M.R.; Chlon, C.H.T.; Sio, C.F.; Reibling, K.; Swanson, T.

    2011-01-01

    Background, Motivation and Objective: Localized drug delivery couldimprove the therapeutic efficacy for treatment of pathological lesions and reduce toxic exposure to healthy organs and tissues. The objective is to develop image-guided, ultrasound-activated tumor chemotherapy with intravenously admi

  8. Low p21(Waf1/Cip1) protein level sensitizes testicular germ cell tumor cells to Fas-mediated apoptosis

    NARCIS (Netherlands)

    Spierings, DCJ; de Vries, EGE; Stel, AJ; Rietstap, NT; Vellenga, E; de Jong, S

    2004-01-01

    In the present study, we investigated the relation between p21 expression and the sensitivity of testicular germ cell tumor (TGCT) cells to apoptotic stimuli. Despite similar cisplatin-induced wild-type p53 accumulation, the TGCT cell lines Tera and Scha expressed low p21 protein and mRNA levels in

  9. Chaperone-rich tumor cell lysate-mediated activation of antigen-presenting cells resists regulatory T cell suppression.

    Science.gov (United States)

    Larmonier, Nicolas; Cantrell, Jessica; Lacasse, Collin; Li, Gang; Janikashvili, Nona; Situ, Elaine; Sepassi, Marjan; Andreansky, Samita; Katsanis, Emmanuel

    2008-04-01

    CD4(+)CD25(+) regulatory T lymphocytes (Tregs) critically contribute to the mechanisms of cancer-induced tolerance. These cells suppress anti-tumoral CD8(+) and CD4(+) T lymphocytes and can also restrain the function of APCs. We have previously documented the immunostimulatory effects of a chaperone-rich cell lysate (CRCL) anti-cancer vaccine. Tumor-derived CRCL induces tumor immunity in vivo, partly by promoting dendritic cell (DC) and macrophage activation. In the current study, we evaluated the effects of CD4(+)CD25(+)forkhead box P3(+) Tregs isolated from mice bearing 12B1 bcr-abl(+) leukemia on DC and macrophages that had been activated by 12B1-derived CRCL. CRCL-activated DC and macrophages resisted Treg suppression, as the production of proinflammatory cytokines, the activation of transcription factor NF-kappaB, and their immunostimulatory potential was unaffected by Tregs. Our results thus highlight CRCL as a powerful adjuvant endowed with the capacity to overcome tumor-induced Treg-inhibitory effects on APCs.

  10. Scutellaria flavonoids inhibit tumor-mediated induction of Treg cells via inhibition of TGF-ß1 activity

    Science.gov (United States)

    It has become evident that tumor-induced Treg cell activity is mostly responsible for the sub-optimal response to therapeutic vaccines. Development of neo-adjuvant strategies targeting TGF-ß and Treg cell activity is therefore imperative. Scutellaria extracts or constituent flavonoids have shown e...

  11. Eosinophilic esophagitis, celiac disease, and immunoglobulin E–mediated allergy in a 2-year-old child

    OpenAIRE

    Sánchez-García, S.; Ibánez, M. D.; Martínez-Gómez, M. J.; Escudero, C.; Vereda, A.; Fernández-Rodríguez, M; P. Rodríguez del Río

    2011-01-01

    This communication was presented at XXVI National Congress of SEAIC, Spanish Society of Allergology and Clinical Immunology, Bilbao, Spain, 2008 Celiac disease, eosinophilic esophagitis, and urticaria are 3 manifestations of food allergy with different pathogenic mechanisms. We report the case of a 2-year-old child with digestive symptoms, slow growth, and severe asthma. The results of skin prick tests were positive to several foods. Endoscopy revealed eosinophilic esophagitis ...

  12. Tumor-Selective Response to Antibody-Mediated Targeting of αvβ3 Integrin in Ovarian Cancer

    Directory of Open Access Journals (Sweden)

    Charles N. Landen

    2008-11-01

    Full Text Available The αvβ3 integrin is expressed on proliferating endothelial cells and some cancer cells, but its expression on ovarian cancer cells and its potential as a therapeutic target are unknown. In this study, expression of the αvβ3 integrin on ovarian cancer cell lines and murine endothelial cells was tested, and the effect of a fully humanized monoclonal antibody against αvβ3, Abegrin (etaracizumab, on cell invasion, viability, tumor growth, and the Akt pathway were examined in vitro and in vivo. We found that etaracizumab recognizes αvβ3 on the ovarian cancer cell lines SKOV3ip1, HeyA8, and A2780ip2 (at low levels but not on murine endothelial cells. Etaracizumab treatment decreased ovarian cancer proliferation and invasion. In vivo, tumor-bearing mice treated with etaracizumab alone gave variable results. There was no effect on A2780ip2 growth, but a 36% to 49% tumor weight reduction in the SKOV3ip1 and HeyA8 models was found (P < .05. However, combined etaracizumab and paclitaxel was superior to paclitaxel in the SKOV3ip1 and A2780ip2 models (by 51–73%, P < .001 but not in the HeyA8 model. Treatment with etaracizumab was then noted to decrease p-Akt and p-mTOR in SKOV3ip1, but not in HeyA8, which is Akt-independent. Tumors resected after therapy showed that etaracizumab treatment reduced the proliferating cell nuclear antigen index but not microvessel density. This study identifies tumor cell αvβ3 integrin as an attractive target and defines the Akt pathway as a predictor of response to function-blocking antibody.

  13. Hypoxia mediates mitochondrial biogenesis in hepatocellular carcinoma to promote tumor growth through HMGB1 and TLR9 interaction.

    Science.gov (United States)

    Tohme, Samer; Yazdani, Hamza O; Liu, Yao; Loughran, Patricia; van der Windt, Dirk J; Huang, Hai; Simmons, Richard L; Shiva, Sruti; Tai, Sheng; Tsung, Allan

    2017-07-01

    The ability of cancer cells to survive and grow under hypoxic conditions has been known for decades, but the mechanisms remain poorly understood. Under certain conditions, cancer cells undergo changes in their bioenergetic profile to favor mitochondrial respiration by activating the peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α) and up-regulating mitochondrial biogenesis. In this study, we hypothesized that augmented mitochondrial biogenesis plays a critical role for cancer cells to survive hypoxia. Consistent with this hypothesis, both hypoxic human hepatocellular carcinoma (HCC) tumors and HCC cell lines subjected to hypoxia increase mitochondrial biogenesis. Silencing of PGC-1α in hypoxic HCC cell lines halts their proliferation. Mechanistic investigations in vitro indicated that intracellular high mobility group box 1 (HMGB1) protein, a nuclear protein overexpressed in HCC, is essential for the process. Silencing of HMGB1 in hypoxic HCC cell lines resulted in a significant decrease in PGC-1α activation and mitochondrial biogenesis. Without HMGB1, hypoxic HCC cells had significantly reduced adenosine triphosphate production, decreased cellular proliferation, and increased apoptosis. In a diethylnitrosamine-induced murine model of HCC, genetic blocking of HMGB1 in hypoxic tumors resulted in a significant decrease in tumor growth. Tumors lacking HMGB1 had a significant reduction in mitochondrial biogenesis and a significant increase in mitochondrial dysfunction. Further in vitro mechanistic experiments indicated that during hypoxia HMGB1 translocates from the nucleus to the cytoplasm and binds to cytoplasmic Toll-like receptor-9. This binding leads to activation of p38 and subsequent phosphorylation of PGC-1α, with resultant up-regulation of mitochondrial biogenesis. Taken together, our findings suggest that during hypoxia HMGB1 up-regulates mitochondrial biogenesis in HCC cancer cells, promoting tumor survival and proliferation

  14. Delta-ALA-mediated fluorescence spectroscopy of gastrointestinal tumors: comparison of in vivo and in vitro results

    Science.gov (United States)

    Vladimirov, B.; Borisova, E.; Avramov, L.

    2007-06-01

    The limitations of standard endoscopy for detection of dysplastic changes of mucosa are significant challenge and initiate development of new photodiagnostic techniques, additional to diagnostic possibilities of standard endoscopic equipment. One of the most widely examined optical modalities is the laser- or light-induced fluorescence spectroscopy (LIFS), because of its rapid and highly sensitive response to early biochemical and morphological changes in biological tissues. In the recent study delta-aminolevulinic acid/protoporphyrin IX is used as fluorescent marker for dysplasia and tumor detection in esophagus and stomach. The δ -ALA is administered per os six hours before measurements at dose 20mg/kg weight. High-power light-emitting diode at 405 nm is used as an excitation source. Special opto-mechanical device is built to use the light guide of standard video-endoscopic system. Through endoscopic instrumental channel a fiber is applied to return information about fluorescence to microspectrometer. The fluorescence detected from in vivo tumor sites has very complex spectral origins. It consists of autofluorescence, fluorescence from exogenous fluorophores and re-absorption from the chromophores accumulated in the tissue investigated. Mucosa autofluorescence lies at 450-600 nm region. The fluorescence of PpIX is clearly pronounced at the 630-710 nm region. Deep minima in the tumor fluorescence signals are observed in the region 540-575 nm, related to hemoglobin re-absorption. Such high hemoglobin content is an indication of the tumors vascularization and it is clearly pronounced in all dysplastic and tumor sites investigated. After formalin conservation for in vitro samples hemoglobin absorption is strongly reduced that increases mucous fluorescence signal in green-yellow spectral region. Simultaneously the maxima at 635 nm and 720 nm are reduced.

  15. Lentiviral MGMT(P140K)-mediated in vivo selection employing a ubiquitous chromatin opening element (A2UCOE) linked to a cellular promoter.

    Science.gov (United States)

    Phaltane, Ruhi; Lachmann, Nico; Brennig, Sebastian; Ackermann, Mania; Modlich, Ute; Moritz, Thomas

    2014-08-01

    Notwithstanding recent successes, insertional mutagenesis as well as silencing and variegation of transgene expression still represent considerable obstacles to hematopoietic gene therapy. This also applies to O(6)-methylguanine DNA methyltransferase (MGMT)-mediated myeloprotection, a concept recently proven clinically effective in the context of glioblastoma therapy. To improve on this situation we here evaluate a SIN-lentiviral vector expressing the MGMT(P140K)-cDNA from a combined A2UCOE/PGK-promoter. In a murine in vivo chemoselection model the A2UCOE.PGK.MGMT construct allowed for significant myeloprotection as well as robust and stable selection of transgenic hematopoietic cells. In contrast, only transient enrichment and severe myelotoxicity was observed for a PGK.MGMT control vector. Selection of A2UCOE.PGK.MGMT-transduced myeloid and lymphoid mature and progenitor cells was demonstrated in the peripheral blood, bone marrow, spleen, and thymus. Unlike the PGK and SFFV promoters used as controls, the A2UCOE.PGK promoter allowed for sustained vector copy number-related transgene expression throughout the experiment indicating an increased resistance to silencing, which was further confirmed by CpG methylation studies of the PGK promoter. Thus, our data support a potential role of the A2UCOE.PGK.MGMT-vector in future MGMT-based myeloprotection and chemoselection strategies, and underlines the suitability of the A2UCOE element to stabilize lentiviral transgene expression in hematopoietic gene therapy.

  16. Ginsenoside metabolite compound K exerts joint-protective effect by interfering with synoviocyte function mediated by TNF-α and Tumor necrosis factor receptor type 2.

    Science.gov (United States)

    Wang, Ying; Chen, Jingyu; Luo, Xuexia; Zhang, Ying; Si, Ming; Wu, Huaxun; Yan, Chang; Wei, Wei

    2016-01-15

    Ginsenoside metabolite compound K (CK), metabolite of the ginsenoside, is considered to exert numerous pharmacological efficacies of ginsenoside, including anti-inflammation and immunoregulatory effects. Rheumatoid arthritis (RA) is a multi-systemic autoimmune disease characterized by hyperplastic synovial membrane and systemic inflammation, which ultimately lead to progressive destructive inflammatory arthropathy. To evaluate the potential joint-protective effects of CK and the underlying mechanism, adjuvant arthritis (AA) was induced by complete Freund's adjuvant in rats. After the onset of arthritis, The effect of CK on AA rats was evaluated by histopathology of the joint. The proliferation of fibroblast-like synoviocyte(FLS) was assayed by the Cell Counting Kit-8.The migration of FLS was assayed by transwell migration assay. Cytokines in the supernatant from FLS were measured by ELISA kit. Expression of Tumor Necrosis Factor Receptor Type 1(TNFR1) and Tumor Necrosis Factor Receptor Type 2(TNFR2) were detected by immunostaining analysis and western blot analysis. CK (80mg/kg) significantly ameliorated the histopathological change of joint in AA rats, balanced the RANKL/OPG ratio and attenuated the proliferation and migration of AA-FLS. CK suppressed the secretion of proinflammatory cytokines TNF-α and downregulated the expression of TNFR2 on AA-FLS. In vitro CK also significantly suppressed proliferation, migration and secretion of AA-FLS mediated by TNF-α. Further studies showed that the effects of CK on AA-FLS were reversed by using glucocorticoid receptor (GR) antagonist (mifepristone). Our data suggest that CK exerts joint-protective effect by interfering with synoviocyte function mediated by TNF-α and TNFR2, and this effect may be mediated by GR.

  17. Structure-activity relationship studies of 1-substituted 3-dodecanoylindole-2-carboxylic acids as inhibitors of cytosolic phospholipase A2-mediated arachidonic acid release in intact platelets.

    Science.gov (United States)

    Griessbach, Klaus; Klimt, Monika; Schulze Elfringhoff, Alwine; Lehr, Matthias

    2002-01-01

    A series of 3-dodecanoylindole-2-carboxylic acid derivatives with varied carboxylic acid substituents at the indole 1-position were synthesized and evaluated for their ability to inhibit arachidonic acid release in human platelets mediated by the cytosolic phospholipase A(2). Structure-activity relationship studies revealed that increasing the polarity of these substituents by the introduction of additional polar groups in the proximity of the carboxylic acid moiety reduced activity. Conformational restriction of the indole-1-carboxylic acid substituents in distinct positions as well as extending the length of these residues led to compounds which did not substantially differ in their potencies.

  18. Presynaptic facilitatory adenosine A2A receptors mediate fade induced by neuromuscular relaxants that exhibit anticholinesterase activity.

    Science.gov (United States)

    Bornia, Elaine Cs; Correia-de-Sá, Paulo; Alves-Do-Prado, Wilson

    2011-03-01

    1. Pancuronium, cisatracurium and vecuronium are antinicotinic agents that, in contrast with d-tubocurarine and hexamethonium, exhibit anticholinesterase activity. Pancuronium-, cisatracurium- and vecuronium-induced fade results from blockade of facilitatory nicotinic receptors on motor nerves, but fade produced by such agents also depends on the presynaptic activation of inhibitory muscarinic M2 receptors by acetylcholine released from motor nerve terminals and activation of inhibitory adenosine A1 receptors by adenosine released from motor nerves and muscles. The participation of presynaptic facilitatory A2A receptors in fade caused by pancuronium, cisatracurium and vecuronium has not yet been investigated. In the present study, we determined the effects of ZM241385, an antagonist of presynaptic facilitatory A2A receptors, on fade produced by these neuromuscular relaxants in the rat phrenic nerve-diaphragm (PND) preparation. 2. The muscles were stimulated indirectly at 75±3Hz to induce a sustained tetanizing muscular contraction. The lowest concentration at which each antinicotinic agent produced fade without modifying initial tetanic tension (presynaptic action) was determined. 3. d-Tubocurarine-induced fade occurred only at 55 nmol/L, a concentration that also reduced maximal tetanic tension (post-synaptic action). At 10 nmol/L, ZM 241385 alone did not produce fade, but it did attenuate pancuronium (0.32 μmol/L)-, cisatracurium (0.32 μmol/L)- and vecuronium (0.36 μmol/L)-induced fade. 4. The fade induced by the 'pure' antinicotinic agents d-tubocurarine (55 nmol/L) and hexamethonium (413 μmol/L) was not altered by 10 nmol/L ZM 241385, indicating that presynaptic adenosine A2A receptors play a significant role in the fade produced by antinicotinic agents when such agents have anticholinesterase activity.

  19. The CC chemokine CK beta-11/MIP-3 beta/ELC/Exodus 3 mediates tumor rejection of murine breast cancer cells through NK cells.

    Science.gov (United States)

    Braun, S E; Chen, K; Foster, R G; Kim, C H; Hromas, R; Kaplan, M H; Broxmeyer, H E; Cornetta, K

    2000-04-15

    CK beta-11 chemoattracts T cells, B cells, dendritic cells, macrophage progenitors, and NK cells and facilitates dendritic cell and T cell interactions in secondary lymphoid tissues. We hypothesized that expression of CK beta-11 in tumor cells may generate antitumor immunity through these interactions. After transduction with the retroviral vector L(CK beta 11)SN, the murine breast cancer cell line C3L5 (C3L5-CK beta 11) showed expression of retroviral mRNA by Northern analysis and production of functional CK beta-11 by chemotaxis of human NK cells to C3L5-CK beta 11 supernatant. Only 10% of mice injected with C3L5-CK beta 11 developed tumors, compared with 100% of mice injected with a transduced control C3L5 line (C3L5-G1N). Importantly, the in vitro growth characteristics of the CK beta-11-transduced cell line were unaffected, suggesting the difference in growth in vivo was a result of chemokine production. Vaccination with C3L5-CK beta 11 partially protected animals from parental C3L5 challenge. Immunodepletion with anti-asialo-GM1 or anti-CD4 during C3L5-CK beta 11 vaccination significantly reduced CK beta-11 antitumor activity compared with control and anti-CD8-treated groups. Splenocytes from NK-depleted animals transferred the acquired immunity generated with C3L5-CK beta 11 vaccination, while splenocytes from the CD4-depleted animals did not. These results indicate, for the first time, that expression of CK beta-11 in a breast cancer cell line mediates rejection of the transduced tumor through a mechanism involving NK and CD4+ cells. Furthermore, CK beta-11-transduced tumor cells generate long-term antitumor immunity that requires CD4+ cells. These studies demonstrate the potential role of CK beta-11 as an adjuvant in stimulating antitumor responses.

  20. Etk/Bmx transactivates vascular endothelial growth factor 2 and recruits phosphatidylinositol 3-kinase to mediate the tumor necrosis factor-induced angiogenic pathway.

    Science.gov (United States)

    Zhang, Rong; Xu, Yingqian; Ekman, Niklas; Wu, Zhenhua; Wu, Jiong; Alitalo, Kari; Min, Wang

    2003-12-19

    Tumor necrosis factor (TNF), via its receptor 2 (TNFR2), induces Etk (or Bmx) activation and Etk-dependent endothelial cell (EC) migration and tube formation. Because TNF receptor 2 lacks an intrinsic kinase activity, we examined the kinase(s) mediating TNF-induced Etk activation. TNF induces a coordinated phosphorylation of vascular endothelial growth factor (VEGF) receptor 2 (VEGFR2) and Etk, which is blocked by VEGFR2-specific inhibitors. In response to TNF, Etk and VEGFR2 form a complex resulting in a reciprocal activation between the two kinases. Subsequently, the downstream phosphatidylinositol 3-kinase (PI3K)-Akt signaling (but not signaling through phospholipase C-gamma) was initiated and directly led to TNF-induced EC migration, which was significantly inhibited by VEGFR2-, PI3K-, or Akt-specific inhibitors. Phosphorylation of VEGFR2 at Tyr-801 and Tyr-1175, the critical sites for VEGF-induced PI3K-Akt signaling, was not involved in TNF-mediated Akt activation. However, TNF induces phosphorylation of Etk at Tyr-566, directly mediating the recruitment of the p85 subunit of PI3K. Furthermore, TNF- but not VEGF-induced activation of VEGFR2, Akt, and EC migration are blunted in EC genetically deficient with Etk. Taken together, our data demonstrated that TNF induces transactivation between Etk and VEGFR2, and Etk directly activates PI3K-Akt angiogenic signaling independent of VEGF-induced VEGFR2-PI3K-Akt signaling pathway.

  1. Unimpaired Autoreactive T-Cell Traffic Within the Central Nervous System During Tumor Necrosis Factor Receptor-Mediated inhibition of Experimental Autoimmune Encephalomyelitis

    Science.gov (United States)

    Korner, Heinrich; Goodsall, Anna L.; Lemckert, Frances A.; Scallon, Bernard J.; Ghrayeb, John; Ford, Andrew L.; Sedgwick, Jonathon D.

    1995-11-01

    The critical role of tumor necrosis factor (TNF) as a mediator in autoimmune inflammatory processes is evident from in vivo studies with TNF-blocking agents. However, the mechanisms by which TNF, and possibly also its homologue lymphotoxin α, contributes to development of pathology in rheumatoid arthritis and Crohn disease and in animal models like experimental autoimmune encephalomyelitis is unclear. Possibilities include regulation of vascular adhesion molecules enabling leukocyte movement into tissues or direct cytokine-mediated effector functions such as mediation of tissue damage. Here we show that administration of a TNF receptor (55 kDa)-IgG fusion protein prevented clinical signs of actively induced experimental autoimmune encephalomyelitis. Significantly, the total number of CD4^+ T lymphocytes isolated from the central nervous system of clinically healthy treated versus diseased control animals was comparable. By using a CD45 congenic model of passively transferred experimental autoimmune encephalomyelitis to enable tracking of myelin basic protein-specific effector T lymphocytes, prevention of clinical signs of disease was again demonstrated in treated animals but without quantitative or qualitative impediment to the movement of autoreactive T lymphocytes to and within the central nervous system. Thus, despite the uninterrupted movement of specific T lymphocytes into the target tissue, subsequent disease development was blocked. This provides compelling evidence for a direct effector role of TNF/lymphotoxin α in autoimmune tissue damage.

  2. Annexin A2 promotes the migration and invasion of human hepatocellular carcinoma cells in vitro by regulating the shedding of CD147-harboring microvesicles from tumor cells.

    Directory of Open Access Journals (Sweden)

    Wei Zhang

    Full Text Available It has been reported that Annexin A2 (ANXA2 is up-regulated in hepatocellular carcinoma (HCC, but the roles of ANXA2 in the migration and invasion of HCC cells have not been determined. In this study, we found that ANXA2-specific siRNA (si-ANXA2 significantly inhibited the migration and invasion of HCC cells co-cultured with fibroblasts in vitro. In addition, the production of MMP-2 by fibroblasts cultured in supernatant collected from si-ANXA2-transfected HCC cells was notably down-regulated. ANXA2 was also found to be co-localized and co-immunoprecipitated with CD147. Further investigation revealed that the expression of ANXA2 in HCC cells affected the shedding of CD147-harboring membrane microvesicles, acting as a vehicle for CD147 in tumor-stromal interactions and thereby regulating the production of MMP-2 by fibroblasts. Together, these results suggest that ANXA2 enhances the migration and invasion potential of HCC cells in vitro by regulating the trafficking of CD147-harboring membrane microvesicles.

  3. Annexin A2 Promotes the Migration and Invasion of Human Hepatocellular Carcinoma Cells In Vitro by Regulating the Shedding of CD147-Harboring Microvesicles from Tumor Cells

    Science.gov (United States)

    Cai, Lei; Song, Zhen-Shun; Cao, Da-Yong; Tao, Kai-Shan; Zhou, Wen-Ping; Chen, Zhi-Nan; Dou, Ke-Feng

    2013-01-01

    It has been reported that Annexin A2 (ANXA2) is up-regulated in hepatocellular carcinoma (HCC), but the roles of ANXA2 in the migration and invasion of HCC cells have not been determined. In this study, we found that ANXA2-specific siRNA (si-ANXA2) significantly inhibited the migration and invasion of HCC cells co-cultured with fibroblasts in vitro. In addition, the production of MMP-2 by fibroblasts cultured in supernatant collected from si-ANXA2-transfected HCC cells was notably down-regulated. ANXA2 was also found to be co-localized and co-immunoprecipitated with CD147. Further investigation revealed that the expression of ANXA2 in HCC cells affected the shedding of CD147-harboring membrane microvesicles, acting as a vehicle for CD147 in tumor-stromal interactions and thereby regulating the production of MMP-2 by fibroblasts. Together, these results suggest that ANXA2 enhances the migration and invasion potential of HCC cells in vitro by regulating the trafficking of CD147-harboring membrane microvesicles. PMID:23950866

  4. Auxins action on Glycine max secretory phospholipase A2 is mediated by the interfacial properties imposed by the phytohormones.

    Science.gov (United States)

    Mariani, María Elisa; Madoery, Ricardo Román; Fidelio, Gerardo Daniel

    2015-07-01

    Secretory phospholipase A2 (sPLA2) are soluble enzymes that catalyze the conversion of phospholipids to lysophospholipids and free fatty acids at membrane interfaces. The effect of IAA and IPA auxins over the activity of recombinant sPLA2 isoforms from Glycine max was studied using membrane model systems including mixed micelles and Langmuir lipid monolayers. Both phytohormones stimulate the activity of both plant sPLA2 using DLPC/Triton mixed micelles as substrate. To elucidate the mechanism of action of the phytohormones, we showed that both auxins are able to self-penetrate lipid monolayers and cause an increment in surface pressure and an expansion of lipid/phytohormone mixed interfaces. The stimulating effect of auxins over phospholipase A2 activity was still present when using Langmuir mixed monolayers as organized substrate regardless of sPLA2 source (plant or animal). All the data suggest that the stimulating effect of auxins over sPLA2 is due to a more favorable interfacial environment rather to a direct effect over the enzyme. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  5. Destabilization of acrosome and elastase influence mediate the release of secretory phospholipase A2 from human spermatozoa

    Institute of Scientific and Technical Information of China (English)

    Jacqueline Leβig; Uta Reibetanz; Jürgen Arnhold; Hans-Jürgen Glander

    2008-01-01

    Aim: To determine the cellular distribution of secretory phospholipase A2 (sPLA2) in dependence on the acrosomal state and under the action of elastase released under inflammatory processes from leukocytes. Methods: Acrosome reaction of spermatozoa was triggered by calcimycin. Human leukocyte elastase was used to simulate in flammatory conditions. To visualize the distribution of sPLA2 and to determine the acrosomal state, immunofluorescence tech-niques and lectin binding combined with confocal laser scanning fluorescence microscopy and flow cytometry were used. Results: Although sPLA2 was detected at the acrosome and tail regions in intact spermatozoa, it disappearedfrom the head region after triggering the acrosome reaction. This release of sPLA2 was associated with enhanced binding of annexin V-fluoroscein isothiocyanate (FITC) to spermatozoa surfaces, intercalation of ethidium-homodimer L and bnding of FITC-iabelled concanavalin A at the acrosomal region. Spermatozoa from healthy subjects treated with elastase were characterized by release of sPLA2, disturbance of acrosome structure, and loss of vitality. Conclusion:The ability of spermatozoa to release secretory phospholipase A2 is related to the acrosomal state. Premature destabi-lization of the acrosome and loss of sPLA2 can occur during silent inflammations in the male genital tract. The distribution pattern of sPLA2 in intact spermatozoa might be an additional parameter for evaluating sperm quality.

  6. Dose-dependent effects of calorie restriction on gene expression, metabolism, and tumor progression are partially mediated by insulin-like growth factor-1.

    Science.gov (United States)

    Nogueira, Leticia M; Lavigne, Jackie A; Chandramouli, Gadisetti V R; Lui, Huaitian; Barrett, J Carl; Hursting, Stephen D

    2012-10-01

    The prevalence of obesity, an established risk and progression factor for breast and many other cancer types, remains very high in the United States and throughout the world. Calorie restriction (CR), a reduced-calorie dietary regimen typically involving a 20-40% reduction in calorie consumption, prevents or reverses obesity, and inhibits mammary and other types of cancer in multiple tumor model systems. Unfortunately, the mechanisms underlying the tumor inhibitory effects of CR are poorly understood, and a better understanding of these mechanisms may lead to new intervention targets and strategies for preventing or controlling cancer. We have previously shown that the anticancer effects of CR are associated with decreased systemic levels of insulin-like growth factor-1 (IGF-1), the primary source of which is liver. We have also reported that CR strongly suppresses tumor development and growth in multiple mammary cancer models. To identify CR-responsive genes and pathways, and to further characterize the role of IGF-1 as a mediator of the anticancer effects of CR, we assessed hepatic and mammary gland gene expression, hormone levels and growth of orthotopically transplanted mammary tumors in control and CR mice with and without exogenous IGF-1. C57BL/6 mice were fed either control AIN-76A diet ad libitum (AL), subjected to 20%, 30%, or 40% CR plus placebo timed-release pellets, or subjected to 30% or 40% CR plus timed-release pellets delivering murine IGF-1 (mIGF-1, 20 μg/day). Compared with AL-fed controls, body weights were decreased 14.3% in the 20% CR group, 18.5% in the 30% CR group, and 38% in the 40% CR group; IGF-1 infusion had no effect on body weight. Hepatic transcriptome analyses indicated that compared with 20% CR, 30% CR significantly modulated more than twice the number of genes and 40% CR more than seven times the number of genes. Many of the genes specific to the 40% CR regimen were hepatic stress-related and/or DNA damage-related genes. Exogenous

  7. Tumor suppressor in lung cancer-1 (TSLC1) mediated by dual-regulated oncolytic adenovirus exerts specific antitumor actions in a mouse model

    Institute of Scientific and Technical Information of China (English)

    Wen LEI; Hong-bin LIU; Shi-bing WANG; Xiu-mei ZHOU; Shui-di ZHENG; Ke-ni GUO; Bu-yun MA

    2013-01-01

    Aim:The tumor suppressor in lung cancer-1 (TSLC1) is a candidate tumor suppressor of lung cancer,and frequently inactivated in primary non-small cell lung cancer (NSCLC).In this study,we investigated the effects of TSLC1 mediated by a dual-regulated oncolytic adenovirus on lung cancer,and the mechanisms underlying the antitumor actions.Methods:The recombinant virus Ad·sp-E1A(△24)-TSLC1 was constructed by inserting the TSLC1 gene into the dual-regulated Ad·spE1A(△24) vector,which contained the survivin promoter and a 24 bp deletion within E1A.The antitumor effects of Ad·sp-E1A(△24)-TSLC1 were evaluated in NCI-H460,A549,and H1299 lung cancer cell lines and the normal fibroblast cell line MRC-5,as well as in A549 xenograft model in nude mice.Cell viability was assessed using MTT assay.The expression of TSLC1 and activation of the caspase signaling pathway were detected by Western blot analyses.The tumor tissues from the xenograft models were examined using H&E staining,IHC,TUNEL,and TEM analyses.Results:Infection of A549 lung cancer cells with Ad·sp-E1A(△24)-TSLC1 induced high level expression of TSLC1.Furthermore,the Ad·spE1A(△△24)-TSLC1 virus dose-dependently suppressed the viability of NCI-H460,A549,and H1299 lung cancer cells,and did not affect MRC-5 normal fibroblast cells.Infection of NCI-H460,A549,and H1299 lung cancer cells with Ad·sp-E1A(△24)-TSLC1 induced apoptosis,and increased activation of caspase-8,caspase-3 and PARR.In A549 xenograft model in nude mice,intratumoral injection of Ad.spE1A(△24)-TSLC1 significantly suppressed the tumor volume,and increased the survival rate (from less than 15% to 87.5% at d 60).Histological studies showed that injection of Ad·sp-E1A(△24)-TSLC1 caused tumor cell apoptosis and virus particle propagation in tumor tissues.Conclusion:The oncolytic adenovirus Ad·sp-E1A(△24)-TSLC1 exhibits specific antitumor effects,and is a promising agent for the treatment of lung cancer.

  8. Peptide-Mediated Tumor Targeting by a Degradable Nano Gene Delivery Vector Based on Pluronic-Modified Polyethylenimine

    Science.gov (United States)

    Wu, Zhaoyong; Zhan, Shuyu; Fan, Wei; Ding, Xueying; Wu, Xin; Zhang, Wei; Fu, Yinghua; Huang, Yueyan; Huang, Xuan; Chen, Rubing; Li, Mingjuan; Xu, Ningyin; Zheng, Yongxia; Ding, Baoyue

    2016-03-01

    Polyethylenimine (PEI) is considered to be a promising non-viral gene delivery vector. To solve the toxicity versus efficacy and tumor-targeting challenges of PEI used as gene delivery vector, we constructed a novel non-viral vector DR5-TAT-modified Pluronic-PEI (Pluronic-PEI-DR5-TAT), which was based on the attachment of low-molecular-weight polyethylenimine (LMW-PEI) to the amphiphilic polymer Pluronic to prepare Pluronic-modified LMW-PEI (Pluronic-PEI). This was then conjugated to a multifunctional peptide containing a cell-penetrating peptide (TAT) and a synthetic peptide that would bind to DR5—a receptor that is overexpressed in cancer cells. The vector showed controlled degradation, favorable DNA condensation and protection performance. The Pluronic-PEI-DR5-TAT/DNA complexes at an N/P ratio of 15:1 were spherical nanoparticles of 122 ± 11.6 nm and a zeta potential of about 22 ± 2.8 mV. In vitro biological characterization results indicated that Pluronic-PEI-DR5-TAT/DNA complexes had a higher specificity for the DR5 receptor and were taken up more efficiently by tumor cells than normal cells, compared to complexes formed with PEI 25 kDa or Pluronic-PEI. Thus, the novel complexes showed much lower cytotoxicity to normal cells and higher gene transfection efficiency in tumor cells than that exhibited by PEI 25 kDa and Pluronic-PEI. In summary, our novel, degradable non-viral tumor-targeting vector is a promising candidate for use in gene therapy.

  9. Immunostimulatory properties and enhanced TNF- α mediated cellular immunity for tumor therapy by C60(OH)20 nanoparticles

    Science.gov (United States)

    Liu, Ying; Jiao, Fang; Qiu, Yang; Li, Wei; Qu, Ying; Tian, Chixia; Li, Yufeng; Bai, Ru; Lao, Fang; Zhao, Yuliang; Chai, Zhifang; Chen, Chunying

    2009-10-01

    Publications concerning the mechanism of biological activity, especially the immunological mechanism of C60(OH)20 nanoparticles, are relatively limited. However, the structure and characteristics of this carbon allotrope have been widely investigated. In this paper, we have demonstrated that water-soluble C60(OH)20 nanoparticles have an efficient anti-tumor activity in vivo, and show specific immunomodulatory effects to the immune cells, such as T cells and macrophages, both in vivo and in vitro. For example, C60(OH)20 nanoparticles can increase the production of T-helper cell type 1 (Th1) cytokines (IL-2, IFN- γ and TNF-α), and decrease the production of Th2 cytokines (IL-4, IL-5 and IL-6) in serum samples. On the other hand, C60(OH)20 nanoparticles show almost no adverse effect to the viability of immune cells in vitro but stimulate the immune cells to release more cytokines, in particular TNF- α, which plays a key role in the cellular immune process to help eliminate abnormal cells. TNF- α production increased almost three-fold in treated T lymphocytes and macrophages. Accordingly, we conclude that C60(OH)20 nanoparticles have an efficient anti-tumor activity and this effect is associated with an increased CD4+/CD8+ lymphocyte ratio and the enhancement of TNF- α production. The data suggest that C60(OH)20 nanoparticles can improve the immune response to help to scavenge and kill tumor cells.

  10. Survivin-targeting Artificial MicroRNAs Mediated by Adenovirus Suppress Tumor Activity in Cancer Cells and Xenograft Models

    Directory of Open Access Journals (Sweden)

    Yudan Chi

    2014-01-01

    Full Text Available Survivin is highly expressed in most human tumors and fetal tissue, and absent in terminally differentiated cells. It promotes tumor cell proliferation by negatively regulating cell apoptosis and facilitating cell division. Survivin's selective expression pattern suggests that it might be a suitable target for cancer therapy, which would promote death of transformed but not normal cells. This was tested using artificial microRNAs (amiRNAs targeting survivin. After screening, two effective amiRNAs, which knocked down survivin expression, were identified and cloned into a replication-defective adenoviral vector. Tumor cells infected with the recombinant vector downregulated expression of survivin and underwent apoptotic cell death. Further studies showed that apoptosis was associated with increases in caspase 3 and cleaved Poly (ADP-ribose polymerase, and activation of the p53 signaling pathway. Furthermore, amiRNA treatment caused blockade of mitosis and cell cycle arrest at the G2/M phase. In vivo, survivin-targeting amiRNAs expressed by adenoviral vectors effectively delayed growth of hepatocellular and cervical carcinomas in mouse xenograft models. These results indicate that silencing of survivin by amiRNA has potential for treatment of cancer.

  11. Monitoring of the tumor response to nano-graphene oxide-mediated photothermal/photodynamic therapy by diffusion-weighted and BOLD MRI

    Science.gov (United States)

    Cao, Jianbo; An, Hengqing; Huang, Xinglu; Fu, Guifeng; Zhuang, Rongqiang; Zhu, Lei; Xie, Jin; Zhang, Fan

    2016-05-01

    Photothermal therapy (PTT) and photodynamic therapy (PDT) are promising cancer treatment modalities. Because each modality has its own set of advantages and limitations, there has been interest in developing methods that can co-deliver the two regimens for enhanced tumor treatment. Among the efforts, nano-graphene oxide-mediated phototherapies have recently attracted much attention. Nano-graphene oxide has a broad absorbance spectrum and can be loaded with photosensitizers, such as chlorin e6, with high efficiency. Chlorin e6-loaded and PEGylated nano-graphene (GO-PEG-Ce6) can be excited at 660 nm, 808 nm, or both, to induce PDT, PTT, or PDT/PTT combination. Despite the potential of the treatments, there is a lack of a diagnostic tool which can monitor their therapeutic response in a non-invasive and prognostic manner; such an ability is urgently needed for the transformation and translation of the technologies. In this study, we performed diffusion-weighted and blood oxygenation level dependent (BOLD) magnetic resonance imaging (MRI) after GO-PEG-Ce6-mediated PTT, PDT, or PTT/PDT. We found that after efficient PTT, there is a significant increase of the tumor apparent diffusion coefficient (ADC) value in diffusion-weighted imaging (DWI) maps; meanwhile, an efficient PDT led to an increase of in BOLD images. In both the cases, the amplitude of the increase was correlated with the treatment outcomes. More interestingly, a synergistic treatment efficacy was observed when the PTT/PDT combination was applied, and the combination was associated with a greater ADC and increase than when either modality was used alone. In particular, the PTT/PDT condition that induced the most dramatic short-term increase of the ADC value (>70%) caused the most effective tumor control in the long-run, with 60% of the treated animals being tumor-free after 60 days. These results suggest the great promise of the combination of DWI and BOLD MRI as a tool for accurate monitoring and prognosis

  12. Identification of the immunodominant epitope region in phospholipase A2 receptor-mediating autoantibody binding in idiopathic membranous nephropathy.

    Science.gov (United States)

    Kao, Liyo; Lam, Vinson; Waldman, Meryl; Glassock, Richard J; Zhu, Quansheng

    2015-02-01

    Membranous nephropathy (MN) is a common cause of nephrotic syndrome in adults. Recent clinical studies established that >70% of patients with idiopathic (also called primary) MN (IMN) possess circulating autoantibodies targeting the M-type phospholipase A2 receptor-1 (PLA2R) on the surface of glomerular visceral epithelial cells (podocytes). In situ, these autoantibodies trigger the formation of immune complexes, which are hypothesized to cause enhanced glomerular permeability to plasma proteins. Indeed, the level of autoantibody in circulation correlates with the severity of proteinuria in patients. The autoantibody only recognizes the nonreduced form of PLA2R, suggesting that disulfide bonds determine the antigenic epitope conformation. Here, we identified the immunodominant epitope region in PLA2R by probing isolated truncated PLA2R extracellular domains with sera from patients with IMN that contain anti-PLA2R autoantibodies. Patient sera specifically recognized a protein complex consisting of the cysteine-rich (CysR), fibronectin-like type II (FnII), and C-type lectin-like domain 1 (CTLD1) domains of PLA2R only under nonreducing conditions. Moreover, absence of either the CysR or CTLD1 domain prevented autoantibody recognition of the remaining domains. Additional analysis suggested that this three-domain complex contains at least one disulfide bond required for conformational configuration and autoantibody binding. Notably, the three-domain complex completely blocked the reactivity of autoantibodies from patient sera with the full-length PLA2R, and the reactivity of patient sera with the three-domain complex on immunoblots equaled the reactivity with full-length PLA2R. These results indicate that the immunodominant epitope in PLA2R is exclusively located in the CysR-FnII-CTLD1 region.

  13. Interleukin-22-Induced Antimicrobial Phospholipase A2 Group IIA Mediates Protective Innate Immunity of Nonhematopoietic Cells against Listeria monocytogenes.

    Science.gov (United States)

    Okita, Yamato; Shiono, Takeru; Yahagi, Ayano; Hamada, Satoru; Umemura, Masayuki; Matsuzaki, Goro

    2015-12-07

    Listeria monocytogenes is a bacterial pathogen which establishes intracellular parasitism in various cells, including macrophages and nonhematopoietic cells, such as hepatocytes. It has been reported that several proinflammatory cytokines have pivotal roles in innate protection against L. monocytogenes infection. We found that a proinflammatory cytokine, interleukin 22 (IL-22), was expressed by CD3(+) CD4(+) T cells at an early stage of L. monocytogenes infection in mice. To assess the influence of IL-22 on L. monocytogenes infection in hepatocytes, cells of a human hepatocellular carcinoma line, HepG2, were treated with IL-22 before L. monocytogenes infection in vitro. Gene expression analysis of the IL-22-treated HepG2 cells identified phospholipase A2 group IIA (PLA2G2A) as an upregulated antimicrobial molecule. Addition of recombinant PLA2G2A to the HepG2 culture significantly suppressed L. monocytogenes infection. Culture supernatant of the IL-22-treated HepG2 cells contained bactericidal activity against L. monocytogenes, and the activity was abrogated by a specific PLA2G2A inhibitor, demonstrating that HepG2 cells secreted PLA2G2A, which killed extracellular L. monocytogenes. Furthermore, colocalization of PLA2G2A and L. monocytogenes was detected in the IL-22-treated infected HepG2 cells, which suggests involvement of PLA2G2A in the mechanism of intracellular killing of L. monocytogenes by HepG2 cells. These results suggest that IL-22 induced at an early stage of L. monocytogenes infection enhances innate immunity against L. monocytogenes in the liver by stimulating hepatocytes to produce an antimicrobial molecule, PLA2G2A.

  14. Cytosolic phospholipase A2 activation correlates with HER2 overexpression and mediates estrogen-dependent breast cancer cell growth.

    LENUS (Irish Health Repository)

    Caiazza, Francesco

    2010-05-01

    Cytosolic phospholipase A(2)alpha (cPLA(2)alpha) catalyzes the hydrolysis of membrane glycerol-phospholipids to release arachidonic acid as the first step of the eicosanoid signaling pathway. This pathway contributes to proliferation in breast cancer, and numerous studies have demonstrated a crucial role of cyclooxygenase 2 and prostaglandin E(2) release in breast cancer progression. The role of cPLA(2)alpha activation is less clear, and we recently showed that 17beta-estradiol (E2) can rapidly activate cPLA(2)alpha in MCF-7 breast cancer cells. Overexpression or gene amplification of HER2 is found in approximately 30% of breast cancer patients and correlates with a poor clinical outcome and resistance to endocrine therapy. This study reports the first evidence for a correlation between cPLA(2)alpha enzymatic activity and overexpression of the HER2 receptor. The activation of cPLA(2)alpha in response to E2 treatment was biphasic with the first phase dependent on trans-activation through the matrix metalloproteinase-dependent release of heparin-bound epidermal growth factor. EGFR\\/HER2 heterodimerization resulted in downstream signaling through the ERK1\\/2 cascade to promote cPLA(2)alpha phosphorylation at Ser505. There was a correlation between HER2 and cPLA(2)alpha expression in six breast cancer cell lines examined, and inhibition of HER2 activation or expression in the SKBR3 cell line using herceptin or HER2-specific small interfering RNA, respectively, resulted in decreased activation and expression of cPLA(2)alpha. Pharmacological blockade of cPLA(2)alpha using a specific antagonist suppressed the growth of both MCF-7 and SKBR3 cells by reducing E2-induced proliferation and by stimulating cellular apoptosis and necrosis. This study highlights cPLAalpha(2) as a potential target for therapeutic intervention in endocrine-dependent and endocrine-independent breast cancer.

  15. Tumor necrosis factor α-converting enzyme (TACE/ADAM17) mediates ectodomain shedding of the scavenger receptor CD163

    DEFF Research Database (Denmark)

    Etzerodt, Anders; Maniecki, Maciej Bogdan; Møller, Kirsten;

    2010-01-01

    is seen between the sCD163 plasma level and the severity of various infectious and inflammatory diseases. In the present analysis of the phorbol ester-induced shedding of sCD163 in CD163 cDNA-transfected HEK293 cells, we used metalloproteinase inhibitors and siRNA-mediated inhibition of metalloproteinases...... to identify TACE/ADAM17 as an enzyme responsible for PMA-induced cleavage of the membrane-proximal region of CD163. As TACE/ADAM17-mediated shedding of TNF-α is up-regulated in macrophages subjected to inflammatory stimuli, the present results now provide a likely explanation for the strong empirical...

  16. A tumor-promoting mechanism mediated by retrotransposon-encoded reverse transcriptase is active in human transformed cell lines

    Science.gov (United States)

    Sciamanna, Ilaria; Gualtieri, Alberto; Cossetti, Cristina; Osimo, Emanuele Felice; Ferracin, Manuela; Macchia, Gianfranco; Aricò, Eleonora; Prosseda, Gianni; Vitullo, Patrizia; Misteli, Tom; Spadafora, Corrado

    2013-01-01

    LINE-1 elements make up the most abundant retrotransposon family in the human genome. Full-length LINE-1 elements encode a reverse transcriptase (RT) activity required for their own retrotranpsosition as well as that of non-autonomous Alu elements. LINE-1 are poorly expressed in normal cells and abundantly in cancer cells. Decreasing RT activity in cancer cells, by either LINE-1-specific RNA interference, or by RT inhibitory drugs, was previously found to reduce proliferation and promote differentiation and to antagonize tumor growth in animal models. Here we have investigated how RT exerts these global regulatory functions. We report that the RT inhibitor efavirenz (EFV) selectively downregulates proliferation of transformed cell lines, while exerting only mild effects on non-transformed cells; this differential sensitivity matches a differential RT abundance, which is high in the former and undetectable in the latter. Using CsCl density gradients, we selectively identify Alu and LINE-1 containing DNA:RNA hybrid molecules in cancer but not in normal cells. Remarkably, hybrid molecules fail to form in tumor cells treated with EFV under the same conditions that repress proliferation and induce the reprogramming of expression profiles of coding genes, microRNAs (miRNAs) and ultraconserved regions (UCRs). The RT-sensitive miRNAs and UCRs are significantly associated with Alu sequences. The results suggest that LINE-1-encoded RT governs the balance between single-stranded and double-stranded RNA production. In cancer cells the abundant RT reverse-transcribes retroelement-derived mRNAs forming RNA:DNA hybrids. We propose that this impairs the formation of double-stranded RNAs and the ensuing production of small regulatory RNAs, with a direct impact on gene expression. RT inhibition restores the ‘normal’ small RNA profile and the regulatory networks that depend on them. Thus, the retrotransposon-encoded RT drives a previously unrecognized mechanism crucial to the

  17. Caffeine mediates sustained inactivation of breast cancer-associated myofibroblasts via up-regulation of tumor suppressor genes.

    Directory of Open Access Journals (Sweden)

    Mysoon M Al-Ansari

    Full Text Available BACKGROUND: Active cancer-associated fibroblasts (CAFs or myofibroblasts play important roles not only in the development and progression of breast carcinomas, but also in their prognosis and treatment. Therefore, targeting these cells through suppressing their supportive procarcinogenic paracrine effects is mandatory for improving the current therapies that are mainly targeting tumor cells. To this end, we investigated the effect of the natural and pharmacologically safe molecule, caffeine, on CAF cells and their various procarcinogenic effects. METHODOLOGY/PRINCIPAL FINDINGS: We have shown here that caffeine up-regulates the tumor suppressor proteins p16, p21, p53 and Cav-1, and reduces the expression/secretion of various cytokines (IL-6, TGF-β, SDF-1 and MMP-2, and down-regulates α-SMA. Furthermore, caffeine suppressed the migratory/invasiveness abilities of CAF cells through PTEN-dependent Akt/Erk1/2 inactivation. Moreover, caffeine reduced the paracrine pro-invasion/-migration effects of CAF cells on breast cancer cells. These results indicate that caffeine can inactivate breast stromal myofibroblasts. This has been confirmed by showing that caffeine also suppresses the paracrine pro-angiogenic effect of CAF cells through down-regulating HIF-1αand its downstream effector VEGF-A. Interestingly, these effects were sustained in absence of caffeine. CONCLUSION/SIGNIFICANCE: The present findings provide a proof of principle that breast cancer myofibroblasts can be inactivated, and thereby caffeine may provide a safe and effective prevention against breast tumor growth/recurrence through inhibition of the procarcinogenic effects of active stromal fibroblasts.

  18. Caffeine Mediates Sustained Inactivation of Breast Cancer-Associated Myofibroblasts via Up-Regulation of Tumor Suppressor Genes

    Science.gov (United States)

    Al-Ansari, Mysoon M.; Aboussekhra, Abdelilah

    2014-01-01

    Background Active cancer-associated fibroblasts (CAFs) or myofibroblasts play important roles not only in the development and progression of breast carcinomas, but also in their prognosis and treatment. Therefore, targeting these cells through suppressing their supportive procarcinogenic paracrine effects is mandatory for improving the current therapies that are mainly targeting tumor cells. To this end, we investigated the effect of the natural and pharmacologically safe molecule, caffeine, on CAF cells and their various procarcinogenic effects. Methodology/Principal Findings We have shown here that caffeine up-regulates the tumor suppressor proteins p16, p21, p53 and Cav-1, and reduces the expression/secretion of various cytokines (IL-6, TGF-β, SDF-1 and MMP-2), and down-regulates α-SMA. Furthermore, caffeine suppressed the migratory/invasiveness abilities of CAF cells through PTEN-dependent Akt/Erk1/2 inactivation. Moreover, caffeine reduced the paracrine pro-invasion/−migration effects of CAF cells on breast cancer cells. These results indicate that caffeine can inactivate breast stromal myofibroblasts. This has been confirmed by showing that caffeine also suppresses the paracrine pro-angiogenic effect of CAF cells through down-regulating HIF-1αand its downstream effector VEGF-A. Interestingly, these effects were sustained in absence of caffeine. Conclusion/Significance The present findings provide a proof of principle that breast cancer myofibroblasts can be inactivated, and thereby caffeine may provide a safe and effective prevention against breast tumor growth/recurrence through inhibition of the procarcinogenic effects of active stromal fibroblasts. PMID:24595168

  19. A tumor-promoting mechanism mediated by retrotransposon-encoded reverse transcriptase is active in human transformed cell lines.

    Science.gov (United States)

    Sciamanna, Ilaria; Gualtieri, Alberto; Cossetti, Cristina; Osimo, Emanuele Felice; Ferracin, Manuela; Macchia, Gianfranco; Aricò, Eleonora; Prosseda, Gianni; Vitullo, Patrizia; Misteli, Tom; Spadafora, Corrado

    2013-12-01

    LINE-1 elements make up the most abundant retrotransposon family in the human genome. Full-length LINE-1 elements encode a reverse transcriptase (RT) activity required for their own retrotranpsosition as well as that of non-autonomous Alu elements. LINE-1 are poorly expressed in normal cells and abundantly in cancer cells. Decreasing RT activity in cancer cells, by either LINE-1-specific RNA interference, or by RT inhibitory drugs, was previously found to reduce proliferation and promote differentiation and to antagonize tumor growth in animal models. Here we have investigated how RT exerts these global regulatory functions. We report that the RT inhibitor efavirenz (EFV) selectively downregulates proliferation of transformed cell lines, while exerting only mild effects on non-transformed cells; this differential sensitivity matches a differential RT abundance, which is high in the former and undetectable in the latter. Using CsCl density gradients, we selectively identify Alu and LINE-1 containing DNA:RNA hybrid molecules in cancer but not in normal cells. Remarkably, hybrid molecules fail to form in tumor cells treated with EFV under the same conditions that repress proliferation and induce the reprogramming of expression profiles of coding genes, microRNAs (miRNAs) and ultraconserved regions (UCRs). The RT-sensitive miRNAs and UCRs are significantly associated with Alu sequences. The results suggest that LINE-1-encoded RT governs the balance between single-stranded and double-stranded RNA production. In cancer cells the abundant RT reverse-transcribes retroelement-derived mRNAs forming RNA:DNA hybrids. We propose that this impairs the formation of double-stranded RNAs and the ensuing production of small regulatory RNAs, with a direct impact on gene expression. RT inhibition restores the 'normal' small RNA profile and the regulatory networks that depend on them. Thus, the retrotransposon-encoded RT drives a previously unrecognized mechanism crucial to the

  20. Tumor necrosis factor α-converting enzyme (TACE/ADAM17) mediates ectodomain shedding of the scavenger receptor CD163

    DEFF Research Database (Denmark)

    Etzerodt, Anders; Maniecki, Maciej Bogdan; Møller, Kirsten

    2010-01-01

    CD163 is expressed specifically in the monocyte/macrophage lineage, where it mediates uptake of haptoglobin-hemoglobin complexes, leading to metabolism of the oxidative heme molecule. Shedding of the CD163 ectodomain from the cell surface produces a sCD163 plasma protein, and a positive correlation...... is seen between the sCD163 plasma level and the severity of various infectious and inflammatory diseases. In the present analysis of the phorbol ester-induced shedding of sCD163 in CD163 cDNA-transfected HEK293 cells, we used metalloproteinase inhibitors and siRNA-mediated inhibition of metalloproteinases...... to identify TACE/ADAM17 as an enzyme responsible for PMA-induced cleavage of the membrane-proximal region of CD163. As TACE/ADAM17-mediated shedding of TNF-alpha is up-regulated in macrophages subjected to inflammatory stimuli, the present results now provide a likely explanation for the strong empirical...

  1. 2-(1-Hexyn-1-yl)adenosine-induced intraocular hypertension is mediated via K+ channel opening through adenosine A2A receptor in rabbits.

    Science.gov (United States)

    Konno, Takashi; Uchibori, Takehiro; Nagai, Akihiko; Kogi, Kentaro; Nakahata, Norimichi

    2005-08-22

    The present study was performed to clarify the mechanism of change in intraocular pressure by 2-(1-hexyn-1-yl)adenosine (2-H-Ado), a selective adenosine A2 receptor agonist, in rabbits. 2-H-Ado (0.1%, 50 microl)-induced ocular hypertension (E(max): 7.7 mm Hg) was inhibited by an adenosine A2A receptor antagonist 1,3,7-trimethyl-8-(3-chlorostyryl)xanthine, ATP-sensitive K+ channel blocker glibenclamide or 5-hydroxydecanoic acid, but not by an adenosine A1 receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine, an adenosine A2B receptor antagonist alloxazine or a cyclooxygenase inhibitor indomethacin. The outflow facility induced by 2-H-Ado seems to be independent of increase in intraocular pressure or ATP-sensitive K+ channel. In contrast, the recovery rate in intraocular pressure decreased by hypertonic saline was accelerated by 2-H-Ado, and this response was dependent on ATP-sensitive K+ channel. These results suggest that 2-H-Ado-induced ocular hypertension is mediated via K+ channel opening through adenosine A2A receptor, and this is probably due to aqueous formation, but independent of change in outflow facility or prostaglandin production.

  2. Cambrian origin of the CYP27C1-mediated vitamin A1-to-A2 switch, a key mechanism of vertebrate sensory plasticity

    Science.gov (United States)

    Morshedian, Ala; Toomery, Matthew B.; Pollock, Gabriel E.; Frederiksen, Rikard; Enright, Jennifer; McCormick, Stephen; Cornwall, M. Carter; Fain, Gordon L.; Corbo, Joseph C.

    2017-01-01

    The spectral composition of ambient light varies across both space and time. Many species of jawed vertebrates adapt to this variation by tuning the sensitivity of their photoreceptors via the expression of CYP27C1, an enzyme that converts vitamin A1 into vitamin A2, thereby shifting the ratio of vitamin A1-based rhodopsin to red-shifted vitamin A2-based porphyropsin in the eye. Here, we show that the sea lamprey (Petromyzon marinus), a jawless vertebrate that diverged from jawed vertebrates during the Cambrian period (approx. 500 Ma), dynamically shifts its photoreceptor spectral sensitivity via vitamin A1-to-A2 chromophore exchange as it transitions between photically divergent aquatic habitats. We further show that this shift correlates with high-level expression of the lamprey orthologue of CYP27C1, specifically in the retinal pigment epithelium as in jawed vertebrates. Our results suggest that the CYP27C1-mediated vitamin A1-to-A2 switch is an evolutionarily ancient mechanism of sensory plasticity that appeared not long after the origin of vertebrates.

  3. Peptide ligand and PEG-mediated long-circulating liposome targeted to FGFR overexpressing tumor in vivo

    Directory of Open Access Journals (Sweden)

    Cai L

    2012-08-01

    Full Text Available Lulu Cai,1,3,† Xianhuo Wang,4,† Wenwen Wang,1,† Neng Qiu,1 Jiaolin Wen,1 Xingmei Duan,1 Xia Li,1 Xiang Chen,1 Li Yang,1 Zhiyong Qian,1 Yuquan Wei,1 Lijuan Chen,1,2 1State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, 2State Key Laboratory Breeding Base of Systematic Research, Development and Utilization of Chinese Medicine, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, 3Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital, Sichuan Chengdu, China; 4Tianjin Medical University Cancer Institute and Hospital, Department of Lymphoma, Sino-US Center for Lymphoma and Leukemia, Key Laboratory of Cancer Prevention and Therapy, Tianjin Medical University, Tianjin, China†These authors equally contributed to this researchBackground and methods: Paclitaxel, a widely used antitumor agent, has limited clinical application due to its hydrophobicity and systemic toxicity. To achieve sustained and targeted delivery of paclitaxel to tumor sites, liposomes composed of egg phosphatidylcholine, cholesterol, and distearolyphosphatidyl ethanolamine-N-poly(ethylene glycol (PEG2000 were prepared by a lipid film method. In addition, the liposomes also contained truncated fibroblast growth factor fragment-PEG-cholesterol as a ligand targeting the tumor marker fibroblast growth factor receptor. Physicochemical characteristics, such as particle size, zeta potential, entrapment efficiency, and release profiles were investigated. Pharmacokinetics and biodistribution were evaluated in C57BL/6 J mice bearing B16 melanoma after intravenous injection of paclitaxel formulated in Cremophor EL (free paclitaxel, conventional liposomes (CL-PTX, or in targeted PEGylated liposomes (TL-PTX.Results: Compared with CL-PTX and free paclitaxel, TL-PTX prolonged the half-life of paclitaxel by 2.01-fold and 3.40-fold, respectively, in plasma and improved the AUC0→t values of paclitaxel by

  4. The chemokine CCL5 induces CCR1-mediated hyperalgesia in mice inoculated with NCTC 2472 tumoral cells.

    Science.gov (United States)

    Pevida, M; Lastra, A; Meana, Á; Hidalgo, A; Baamonde, A; Menéndez, Luis

    2014-02-14

    Although the expression of the chemokine receptor CCR1 has been demonstrated in several structures related to nociception, supporting the nociceptive role of chemokines able to activate it, the involvement of CCR1 in neoplastic pain has not been previously assessed. We have assayed the effects of a CCR1 antagonist, J113863, in two murine models of neoplastic hyperalgesia based on the intratibial injection of either NCTC 2472 fibrosarcoma cells, able to induce osteolytic bone injury, or B16-F10 melanoma cells, associated to mixed osteolytic/osteoblastic bone pathological features. The systemic administration of J113863 inhibited thermal and mechanical hyperalgesia but not mechanical allodynia in mice inoculated with NCTC 2472 cells. Moreover, in these mice, thermal hyperalgesia was counteracted following the peritumoral (10-30μg) but not spinal (3-5μg) administration of J113863. In contrast, hyperalgesia and allodynia measured in mice inoculated with B16-F10 cells remained unaffected after the administration of J113863. The inoculation of tumoral cells did not modify the levels of CCL3 at tumor or spinal cord. In contrast, although the concentration of CCL5 remained unmodified in mice inoculated with B16-F10 cells, increased levels of this chemokine were measured in tumor-bearing limbs, but not the spinal cord, of mice inoculated with NCTC 2472 cells. Increased levels of CCL5 were also found following the incubation of NCTC 2472, but not B16-F10, cells in the corresponding culture medium. The intraplantar injection of CCL5 (0.5ng) to naïve mice evoked thermal hyperalgesia prevented by the coadministration of J113863 or the CCR5 antagonist, d-Ala-peptide T-amide (DAPTA), demonstrating that CCL5 can induce thermal hyperalgesia in mice through the activation of CCR1 or CCR5. However, contrasting with the inhibitory effect evoked by J113863, the systemic administration of DAPTA did not prevent tumoral hyperalgesia. Finally, the peritumoral administration of an anti

  5. Human Immunodeficiency Virus Type 1 Nef Binds to Tumor Suppressor p53 and Protects Cells against p53-Mediated Apoptosis

    OpenAIRE

    2002-01-01

    The nef gene product of human immunodeficiency virus type 1 (HIV-1) is important for the induction of AIDS, and key to its function is its ability to manipulate T-cell function by targeting cellular signal transduction proteins. We reported that Nef coprecipitates a multiprotein complex from cells which contains tumor suppressor protein p53. We now show that Nef interacts directly with p53. Binding assays showed that an N-terminal, 57-residue fragment of Nef (Nef 1-57) contains the p53-bindin...

  6. Apigenin induces apoptosis via tumor necrosis factor receptor- and Bcl-2-mediated pathway and enhances susceptibility of head and neck squamous cell carcinoma to 5-fluorouracil and cisplatin.

    Science.gov (United States)

    Chan, Leong-Perng; Chou, Tzung-Han; Ding, Hsiou-Yu; Chen, Pin-Ru; Chiang, Feng-Yu; Kuo, Po-Lin; Liang, Chia-Hua

    2012-07-01

    Apigenin, a natural plant flavone, may have chemopreventive and therapeutic potentials for anti-inflammatory, antioxidant, and anti-cancer. Nevertheless, the anti-tumor effect of apigenin on human head and neck squamous cell carcinoma (HNSCC) is not fully understood. The antioxidant capacity and protective effects of apigenin against oxidative stress in murine normal embryonic liver BNLCL2 cells are examined. Cell viability, morphologic change, clonogenic survival, cell cycle distribution, reactive oxygen species (ROS) production, glutathione formation, and death receptors- and Bcl-2-mediated caspase pathways of HNSCC SCC25 cells and A431 cells with apigenin are investigated. Apigenin inhibits the growth of SCC25 and A431 cells and induces cell cycle arrest in the G2/M phase. Apigenin has an antioxidant capacity as well as the ability to inhibit lipid peroxidation. It protects BNLCL2 cells against oxidative damage, and is potentially able to prevent cancer. Apigenin increases intracellular ROS levels and reduces levels of glutathione; it also induces cell apoptosis via tumor necrosis factor receptor (TNF-R)-, TNF-related apoptosis-inducing ligand receptor (TRAIL-R)-, and Bcl-2-mediated caspase-dependent cell death pathways in SCC25 cells. The combination of apigenin with 5-fluorouracil (5-Fu) or cisplatin induces the dramatic death of SCC25 cells. Apigenin induces SCC25 cell apoptosis via the up-regulation of both TNF-R and TRAIL-R signaling pathways, and has a synergistic effect on the inhibition of cell proliferation in combination with 5-Fu or cisplatin. These analytical findings suggest that apigenin may be a good therapeutic agent against HNSCC cells. Copyright © 2012 Elsevier B.V. All rights reserved.

  7. Down-regulation of RBP-J mediated by microRNA-133a suppresses dendritic cells and functions as a potential tumor suppressor in osteosarcoma.

    Science.gov (United States)

    Gao, Xuren; Han, Dong; Fan, Weimin

    2016-12-10

    In recent years, immunotherapy for the treatment of tumors have been established. Dendritic cells (DCs) are extremely efficient and professional antigen presenting cells (APCs), which are an important target for immune therapeutic interventions in cancer. In present study, we investigated whether RBP-J signaling regulated by miR-133a was involved in the DCs mediated tumor suppressor in osteosarcoma. DCs were isolated from 30 osteosarcoma patients and 30 healthy subjects. Mouse macrophage-like cell line RAW264.7 were cultured and osteosarcoma mouse model with injection of murine osteosarcoma cell line S180 were established. In osteosarcoma patients, miR-133a expression level of DCs was increased, and RBP-J expression in mRNA and protein levels were decreased. MiR-133a inhibitor promoted maturation and activation of DCs in osteosarcoma patients. In osteosarcoma mouse model, miR-133a mimic suppressed the maturation and activation of spleen DCs, while miR-133a inhibitor promoted them. Overexpression of miR-133a decreased therapeutic effect of DCs on osteosarcoma mice. In RAW264.7 cells, miR-133a was observed to target RBP-J and regulate its expression. MiR-133a mimic inhibited the maturation of DCs in cells exposed to LPS, the effect of which was reversed by overexpression of RBP-J. RBP-J mediated by miR-133a probably contributed to the regulation of DCs maturation and activation in osteosarcoma, which functioned as a therapeutic target for the immunotherapy in cancers. Copyright © 2016. Published by Elsevier Inc.

  8. HBV-specific CD4+ cytotoxic T cells in hepatocellular carcinoma are less cytolytic toward tumor cells and suppress CD8+ T cell-mediated antitumor immunity.

    Science.gov (United States)

    Meng, Fanzhi; Zhen, Shoumei; Song, Bin

    2017-08-01

    In East Asia and sub-Saharan Africa, chronic infection is the main cause of the development of hepatocellular carcinoma, an aggressive cancer with low survival rate. Cytotoxic T cell-based immunotherapy is a promising treatment strategy. Here, we investigated the possibility of using HBV-specific CD4(+) cytotoxic T cells to eliminate tumor cells. The naturally occurring HBV-specific cytotoxic CD4(+) and CD8(+) T cells were identified by HBV peptide pool stimulation. We found that in HBV-induced hepatocellular carcinoma patients, the HBV-specific cytotoxic CD4(+) T cells and cytotoxic CD8(+) T cells were present at similar numbers. But compared to the CD8(+) cytotoxic T cells, the CD4(+) cytotoxic T cells secreted less cytolytic factors granzyme A (GzmA) and granzyme B (GzmB), and were less effective at eliminating tumor cells. In addition, despite being able to secrete cytolytic factors, CD4(+) T cells suppressed the cytotoxicity mediated by CD8(+) T cells, even when CD4(+) CD25(+) regulator T cells were absent. Interestingly, we found that interleukin 10 (IL-10)-secreting Tr1 cells were enriched in the cytotoxic CD4(+) T cells. Neutralization of IL-10 abrogated the suppression of CD8(+) T cells by CD4(+) CD25(-) T cells. Neither the frequency nor the absolute number of HBV-specific CD4(+) cytotoxic T cells were correlated with the clinical outcome of advanced stage hepatocellular carcinoma patients. Together, this study demonstrated that in HBV-related hepatocellular carcinoma, CD4(+) T cell-mediated cytotoxicity was present naturally in the host and had the potential to exert antitumor immunity, but its capacity was limited and was associated with immunoregulatory properties. © 2017 APMIS. Published by John Wiley & Sons Ltd.

  9. Fap2 Mediates Fusobacterium nucleatum Colorectal Adenocarcinoma Enrichment by Binding to Tumor-Expressed Gal-GalNAc.

    Science.gov (United States)

    Abed, Jawad; Emgård, Johanna E M; Zamir, Gideon; Faroja, Mouhammad; Almogy, Gideon; Grenov, Amalie; Sol, Asaf; Naor, Ronit; Pikarsky, Eli; Atlan, Karine A; Mellul, Anna; Chaushu, Stella; Manson, Abigail L; Earl, Ashlee M; Ou, Nora; Brennan, Caitlin A; Garrett, Wendy S; Bachrach, Gilad

    2016-08-10

    Fusobacterium nucleatum is associated with colorectal cancer and promotes colonic tumor formation in preclinical models. However, fusobacteria are core members of the human oral microbiome and less prevalent in the healthy gut, raising questions about how fusobacteria localize to CRC. We identify a host polysaccharide and fusobacterial lectin that explicates fusobacteria abundance in CRC. Gal-GalNAc, which is overexpressed in CRC, is recognized by fusobacterial Fap2, which functions as a Gal-GalNAc lectin. F. nucleatum binding to clinical adenocarcinomas correlates with Gal-GalNAc expression and is reduced upon O-glycanase treatment. Clinical fusobacteria strains naturally lacking Fap2 or inactivated Fap2 mutants show reduced binding to Gal-GalNAc-expressing CRC cells and established CRCs in mice. Additionally, intravenously injected F. nucleatum localizes to mouse tumor tissues in a Fap2-dependent manner, suggesting that fusobacteria use a hematogenous route to reach colon adenocarcinomas. Thus, targeting F. nucleatum Fap2 or host epithelial Gal-GalNAc may reduce fusobacteria potentiation of CRC.

  10. TMV-peptide fusion vaccines induce cell-mediated immune responses and tumor protection in two murine models.

    Science.gov (United States)

    McCormick, Alison A; Corbo, Tina A; Wykoff-Clary, Sherri; Nguyen, Long V; Smith, Mark L; Palmer, Kenneth E; Pogue, Gregory P

    2006-09-29

    Fusion of peptides to viral carriers has proven an effective method for improving cellular immunity. In this study we explore the ability of a plant virus, Tobacco mosaic virus (TMV), to stimulate cellular immunity by interacting directly with immune cells. Fluorescently labeled TMV was incubated in vitro with murine spleen or lymph node cells, and near quantitative labeling of lymphocytes was achieved after 2 h, which persisted for up to 48 h. Direct TMV uptake and upregulation of the CD86 activation marker was measured in nearly all dendritic cells (DCs) by flow cytometry. To demonstrate that TMV can also provide functional antigen delivery and immune stimulation in vivo, two well-characterized T-cell epitopes that provide protection against tumor challenge in mice were fused to TMV coat protein by genetic manipulation, or by chemical conjugation. Vaccination of C57BL/6 mice elicited measurable cellular responses by interferon gamma (IFN gamma) ELISpot and resulted in significantly improved protection from tumor challenge in both the EG.7-Ova and B16 melanoma models. From these results we conclude that TMV was an effective antigen carrier for inducing cellular immune responses to less than 1 microg of peptide.

  11. Suppression of tumor growth in lung cancer xenograft model mice by poly(sorbitol-co-PEI)-mediated delivery of osteopontin siRNA.

    Science.gov (United States)

    Cho, Won-Young; Hong, Seong-Ho; Singh, Bijay; Islam, Mohammad Ariful; Lee, Somin; Lee, Ah Young; Gankhuyag, Nomundelger; Kim, Ji-Eun; Yu, Kyeong-Nam; Kim, Kwang-Ho; Park, Young-Chan; Cho, Chong-Su; Cho, Myung-Haing

    2015-08-01

    Small interfering RNA (siRNA)-mediated gene silencing represents a promising strategy for treating diseases such as cancer; however, specific gene silencing requires an effective delivery system to overcome the instability and low transfection efficiency of siRNAs. To address this issue, a polysorbitol-based transporter (PSOT) was prepared by low molecular weight branched polyethylenimine (bPEI) crosslinked with sorbitol diacrylate (SDA). Osteopontin (OPN) gene, which is highly associated with non-small cell lung cancer (NSCLC) was targeted by siRNA therapy using siRNA targeting OPN (siOPN). Characterization study confirmed that PSOT formed compact complexes with siOPN and protected siOPN against degradation by RNase. PSOT/siOPN complexes demonstrated low cytotoxicity and enhanced transfection efficiency in vitro, suggesting that this carrier may be suitable for gene silencing. In the A549 and H460 lung cancer cell lines, PSOT/siOPN complexes demonstrated significant silencing efficiency at both RNA and protein levels. To study in vivo tumor growth suppression, two lung cancer cell-xenograft mouse models were prepared and PSOT/siOPN complexes were delivered into the mice through intravenous injection. The siOPN-treated groups demonstrated significantly reduced OPN expression at both the RNA and protein levels as well as suppression of tumor volume and weight. Taken together, siOPN delivery using PSOT may present an effective and novel therapeutic system for lung cancer treatment.

  12. Tumor endothelial marker 5 expression in endothelial cells during capillary morphogenesis is induced by the small GTPase Rac and mediates contact inhibition of cell proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Vallon, Mario, E-mail: m.vallon@arcor.de [Nuklearmedizinische Klinik und Poliklinik, Technische Universitaet Muenchen, Ismaninger Strasse 22, 81675 Munich (Germany); Rohde, Franziska; Janssen, Klaus-Peter [Chirurgische Klinik und Poliklinik, Technische Universitaet Muenchen, Munich (Germany); Essler, Markus [Nuklearmedizinische Klinik und Poliklinik, Technische Universitaet Muenchen, Ismaninger Strasse 22, 81675 Munich (Germany)

    2010-02-01

    Tumor endothelial marker (TEM) 5 is an adhesion G-protein-coupled receptor upregulated in endothelial cells during tumor and physiologic angiogenesis. So far, the mechanisms leading to upregulation of TEM5 and its function during angiogenesis have not been identified. Here, we report that TEM5 expression in endothelial cells is induced during capillary-like network formation on Matrigel, during capillary morphogenesis in a three-dimensional collagen I matrix, and upon confluence on a two-dimensional matrix. TEM5 expression was not induced by a variety of soluble angiogenic factors, including VEGF and bFGF, in subconfluent endothelial cells. TEM5 upregulation was blocked by toxin B from Clostridium difficile, an inhibitor of the small GTPases Rho, Rac, and Cdc42. The Rho inhibitor C3 transferase from Clostridium botulinum did not affect TEM5 expression, whereas the Rac inhibitor NSC23766 suppressed TEM5 upregulation. An excess of the soluble TEM5 extracellular domain or an inhibitory monoclonal TEM5 antibody blocked contact inhibition of endothelial cell proliferation resulting in multilayered islands within the endothelial monolayer and increased vessel density during capillary formation. Based on our results we conclude that TEM5 expression during capillary morphogenesis is induced by the small GTPase Rac and mediates contact inhibition of proliferation in endothelial cells.

  13. Transporter-Mediated Drug Interaction Strategy for 5-Aminolevulinic Acid (ALA-Based Photodynamic Diagnosis of Malignant Brain Tumor: Molecular Design of ABCG2 Inhibitors

    Directory of Open Access Journals (Sweden)

    Toshihisa Ishikawa

    2011-09-01

    Full Text Available Photodynamic diagnosis (PDD is a practical tool currently used in surgical operation of aggressive brain tumors, such as glioblastoma. PDD is achieved by a photon-induced physicochemical reaction which is induced by excitation of protoporphyrin IX (PpIX exposed to light. Fluorescence-guided gross-total resection has recently been developed in PDD, where 5-aminolevulinic acid (ALA or its ester is administered as the precursor of PpIX. ALA induces the accumulation of PpIX, a natural photo-sensitizer, in cancer cells. Recent studies provide evidence that adenosine triphosphate (ATP-binding cassette (ABC transporter ABCG2 plays a pivotal role in regulating the cellular accumulation of porphyrins in cancer cells and thereby affects the efficacy of PDD. Protein kinase inhibitors are suggested to potentially enhance the PDD efficacy by blocking ABCG2-mediated porphyrin efflux from cancer cells. It is of great interest to develop potent ABCG2-inhibitors that can be applied to PDD for brain tumor therapy. This review article addresses a pivotal role of human ABC transporter ABCG2 in PDD as well as a new approach of quantitative structure-activity relationship (QSAR analysis to design potent ABCG2-inhibitors.

  14. RNAi-mediated knockdown of pituitary tumor-transforming gene-1 (PTTG1) suppresses the proliferation and invasive potential of PC3 human prostate cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Huang, S.Q. [Department of Urology and Center of Nephrology, Xinqiao Hospital, Third Military Medical University, Chongqing (China); Institute of Urology, Peking University and Department of Urology, First Hospital, Peking University, Beijing (China); Liao, Q.J.; Wang, X.W. [Department of Urology and Center of Nephrology, Xinqiao Hospital, Third Military Medical University, Chongqing (China); Xin, D.Q. [Institute of Urology, Peking University and Department of Urology, First Hospital, Peking University, Beijing (China); Chen, S.X.; Wu, Q.J.; Ye, G. [Department of Urology and Center of Nephrology, Xinqiao Hospital, Third Military Medical University, Chongqing (China)

    2012-08-10

    Pituitary tumor-transforming gene-1 (PTTG1) is a proto-oncogene that promotes tumorigenesis and metastasis in numerous cell types and is overexpressed in a variety of human tumors. We have demonstrated that PTTG1 expression was up-regulated in both human prostate cancer specimens and prostate cancer cell lines. For a more direct assessment of the function of PTTG1 in prostate tumorigenesis, RNAi-mediated knockdown was used to selectively decrease PTTG1 expression in PC3 human prostate tumor cells. After three weeks of selection, colonies stably transfected with PTTG1-targeted RNAi (the knockdown PC3 cell line) or empty vector (the control PC3 cell line) were selected and expanded to investigate the role of PTTG1 expression in PC3 cell growth and invasion. Cell proliferation rate was significantly slower (28%) in the PTTG1 knockdown line after 6 days of growth as indicated by an MTT cell viability assay (P < 0.05). Similarly, a soft agar colony formation assay revealed significantly fewer (66.7%) PTTG1 knockdown PC3 cell colonies than control colonies after three weeks of growth. In addition, PTTG1 knockdown resulted in cell cycle arrest at G1 as indicated by fluorescence-activated cell sorting. The PTTG1 knockdown PC3 cell line also exhibited significantly reduced migration through Matrigel in a transwell assay of invasive potential, and down-regulation of PTTG1 could lead to increased sensitivity of these prostate cancer cells to a commonly used anticancer drug, taxol. Thus, PTTG1 expression is crucial for PC3 cell proliferation and invasion, and could be a promising new target for prostate cancer therapy.

  15. CLEC12A-Mediated Antigen Uptake and Cross-Presentation by Human Dendritic Cell Subsets Efficiently Boost Tumor-Reactive T Cell Responses.

    Science.gov (United States)

    Hutten, Tim J A; Thordardottir, Soley; Fredrix, Hanny; Janssen, Lisanne; Woestenenk, Rob; Tel, Jurjen; Joosten, Ben; Cambi, Alessandra; Heemskerk, Mirjam H M; Franssen, Gerben M; Boerman, Otto C; Bakker, Lex B H; Jansen, Joop H; Schaap, Nicolaas; Dolstra, Harry; Hobo, Willemijn

    2016-10-01

    Potent immunotherapies are urgently needed to boost antitumor immunity and control disease in cancer patients. As dendritic cells (DCs) are the most powerful APCs, they are an attractive means to reinvigorate T cell responses. An appealing strategy to use the effective Ag processing and presentation machinery, T cell stimulation and cross-talk capacity of natural DC subsets is in vivo tumor Ag delivery. In this context, endocytic C-type lectin receptors are attractive targeting molecules. In this study, we investigated whether CLEC12A efficiently delivers tumor Ags into human DC subsets, facilitating effective induction of CD4(+) and CD8(+) T cell responses. We confirmed that CLEC12A is selectively expressed by myeloid cells, including the myeloid DC subset (mDCs) and the plasmacytoid DC subset (pDCs). Moreover, we demonstrated that these DC subsets efficiently internalize CLEC12A, whereupon it quickly translocates to the early endosomes and subsequently routes to the lysosomes. Notably, CLEC12A Ab targeting did not negatively affect DC maturation or function. Furthermore, CLEC12A-mediated delivery of keyhole limpet hemocyanin resulted in enhanced proliferation and cytokine secretion by keyhole limpet hemocyanin-experienced CD4(+) T cells. Most importantly, CLEC12A-targeted delivery of HA-1 long peptide resulted in efficient Ag cross-presentation by mDCs and pDCs, leading to strong ex vivo activation of HA-1-specific CD8(+) T cells of patients after allogeneic stem cell transplantation. Collectively, these data indicate that CLEC12A is an effective new candidate with great potential for in vivo Ag delivery into mDCs and pDCs, thereby using the specialized functions and cross-talk capacity of these DC subsets to boost tumor-reactive T cell immunity in cancer patients.

  16. Steroid receptor coactivator 1 deficiency increases MMTV-neu mediated tumor latency and differentiation specific gene expression, decreases metastasis, and inhibits response to PPAR ligands

    Directory of Open Access Journals (Sweden)

    Crowe David L

    2010-11-01

    Full Text Available Abstract Background The peroxisome proliferator activated receptor (PPAR subgroup of the nuclear hormone receptor superfamily is activated by a variety of natural and synthetic ligands. PPARs can heterodimerize with retinoid X receptors, which have homology to other members of the nuclear receptor superfamily. Ligand binding to PPAR/RXRs results in recruitment of transcriptional coactivator proteins such as steroid receptor coactivator 1 (SRC-1 and CREB binding protein (CBP. Both SRC-1 and CBP are histone acetyltransferases, which by modifying nucleosomal histones, produce more open chromatin structure and increase transcriptional activity. Nuclear hormone receptors can recruit limiting amounts of coactivators from other transcription factor binding sites such as AP-1, thereby inhibiting the activity of AP-1 target genes. PPAR and RXR ligands have been used in experimental breast cancer therapy. The role of coactivator expression in mammary tumorigenesis and response to drug therapy has been the subject of recent studies. Methods We examined the effects of loss of SRC-1 on MMTV-neu mediated mammary tumorigenesis. Results SRC-1 null mutation in mammary tumor prone mice increased the tumor latency period, reduced tumor proliferation index and metastasis, inhibited response to PPAR and RXR ligands, and induced genes involved in mammary gland differentiation. We also examined human breast cancer cell lines overexpressing SRC-1 or CBP. Coactivator overexpression increased cellular proliferation with resistance to PPAR and RXR ligands and remodeled chromatin of the proximal epidermal growth factor receptor promoter. Conclusions These results indicate that histone acetyltransferases play key roles in mammary tumorigenesis and response to anti-proliferative therapies.

  17. Antibody-mediated targeting of iron oxide nanoparticles to the folate receptor alpha increases tumor cell association in vitro and in vivo

    Directory of Open Access Journals (Sweden)

    Ndong C

    2015-04-01

    Full Text Available Christian Ndong,1 Seiko Toraya-Brown,2 Katsiaryna Kekalo,1 Ian Baker,1 Tillman U Gerngross,1,3,4 Steven N Fiering,2,5,6 Karl E Griswold1,3,6 1Thayer School of Engineering, Dartmouth, Hanover, NH, USA; 2Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH, USA; 3Department of Biological Sciences, Dartmouth, Hanover, NH, USA; 4Department of Chemistry, Dartmouth, Hanover, NH, USA; 5Department of Genetics, Geisel School of Medicine at Dartmouth, Hanover, NH, USA; 6Norris Cotton Cancer Center, Lebanon, NH, USA Abstract: Active molecular targeting has become an important aspect of nanoparticle development for oncology indications. Here, we describe molecular targeting of iron oxide nanoparticles (IONPs to the folate receptor alpha (FOLRα using an engineered antibody fragment (Ffab. Compared to control nanoparticles targeting the non-relevant botulinum toxin, the Ffab-IONP constructs selectively accumulated on FOLRα-overexpressing cancer cells in vitro, where they exhibited the capacity to internalize into intracellular vesicles. Similarly, Ffab-IONPs homed to FOLRα-positive tumors upon intraperitoneal administration in an orthotopic murine xenograft model of ovarian cancer, whereas negative control particles showed no detectable tumor accumulation. Interestingly, Ffab-IONPs built with custom 120 nm nanoparticles exhibited lower in vitro targeting efficiency when compared to those built with commercially sourced 180 nm nanoparticles. In vivo, however, the two Ffab-IONP platforms achieved equivalent tumor homing, although the smaller 120 nm IONPs were more prone to liver sequestration. Overall, the results show that Ffab-mediated targeting of IONPs yields specific, high-level accumulation within cancer cells, and this fact suggests that Ffab-IONPs could have future utility in ovarian cancer diagnostics and therapy. Keywords: nanoparticle targeting, antibody fragment, biodistribution, ovarian cancer

  18. INPP4B-mediated tumor resistance is associated with modulation of glucose metabolism via hexokinase 2 regulation in laryngeal cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Min, Joong Won [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Kim, Kwang Il [Molecular Imaging Research Center, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Kim, Hyun-Ah; Kim, Eun-Kyu; Noh, Woo Chul [Department of Surgery, Korea Cancer Center Hospital, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Jeon, Hong Bae [Biomedical Research Institute, MEDIPOST Co., Ltd., Seoul (Korea, Republic of); Cho, Dong-Hyung [Graduate School of East-West Medical Science, Kyung Hee University, Gyeonggi-do (Korea, Republic of); Oh, Jeong Su [Department of Genetic Engineering, Sungkyunkwan University, Suwon (Korea, Republic of); Park, In-Chul; Hwang, Sang-Gu [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Kim, Jae-Sung, E-mail: jaesung@kirams.re.kr [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)

    2013-10-11

    Highlights: •HIF-1α-regulated INPP4B enhances glycolysis. •INPP4B regulates aerobic glycolysis by inducing HK2 via Akt-mTOR pathway. •Blockage of INPP4B and HK2 sensitizes radioresistant laryngeal cancer cells to radiation and anticancer drug. •INPP4B is associated with HK2 in human laryngeal cancer tissues. -- Abstract: Inositol polyphosphate 4-phosphatase type II (INPP4B) was recently identified as a tumor resistance factor in laryngeal cancer cells. Herein, we show that INPP4B-mediated resistance is associated with increased glycolytic phenotype. INPP4B expression was induced by hypoxia and irradiation. Intriguingly, overexpression of INPP4B enhanced aerobic glycolysis. Of the glycolysis-regulatory genes, hexokinase 2 (HK2) was mainly regulated by INPP4B and this regulation was mediated through the Akt-mTOR pathway. Notably, codepletion of INPP4B and HK2 markedly sensitized radioresistant laryngeal cancer cells to irradiation or anticancer drug. Moreover, INPP4B was significantly associated with HK2 in human laryngeal cancer tissues. Therefore, these results suggest that INPP4B modulates aerobic glycolysis via HK2 regulation in radioresistant laryngeal cancer cells.

  19. Induction of matrix metalloproteinase-1 by tumor necrosis factor-α is mediated by interleukin-6 in cultured fibroblasts of keratoconus.

    Science.gov (United States)

    Du, Genlai; Liu, Chengxing; Li, Xiaona; Chen, Weiyi; He, Rui; Wang, Xiaojun; Feng, Pengfei; Lan, Weiwei

    2016-12-01

    Inflammatory molecules and matrix metalloproteinase (MMPs) have been found over-expressed in the tear film of patients with keratoconus. However, the mechanistic link between inflammatory molecules and MMPs in the pathogenesis of keratoconus remains still elusive. Therefore, we investigated the effect of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) on MMP-1 expression and used IL-6 antibody (IL-6 Ab) to examine the role of IL-6 on TNF-α mediated regulation of MMP-1 in fibroblasts of normal cornea and keratoconus. Real-time polymerase chain reaction, Enzyme-linked immunosorbent assay, and Western blot data demonstrated that MMP-1 and IL-6 were expressed in fibroblasts of normal cornea and keratoconus. Levels of MMP-1 and IL-6 were significantly higher in keratoconus than normal cornea. TNF-α treatment led to a significant increase in IL-6 levels. IL-6 treatment induced MMP-1 synthesis in normal cornea and keratoconus. TNF-α increased MMP-1 expression in a dose- and time-dependent manner and this response was completely inhibited by the IL-6 Ab. In conclusion, these results indicate that fibroblasts of keratoconus shows increased levels of IL-6 and MMP-1 gene and protein expression and IL-6 mediates the TNF-α-induced MMP-1 expression.

  20. Coping and quality of life in patients with skin tumors in the follow-up stage: The mediating role of body image and psychological morbidity.

    Science.gov (United States)

    Pereira, M Graça; Baia, Vânia; Machado, José C

    2016-01-01

    This study examined the relationships between coping style, body image, psychological morbidity, and quality of life. A total of 58 patients who were diagnosed with skin tumors, had been submitted to surgery, and were in the follow-up phase answered the following instruments: dermatology life quality index (DLQI), hospital anxiety and depression scales (HADS), body image scale (BIS), and the mini mental adjustment to cancer scale (Mini-MAC). The results showed that patients with a higher use of the coping styles of helplessness/hopelessness, anxious preoccupation, and cognitive avoidance reported a worse quality of life. Body image mediated the relationship between the coping styles of anxious preoccupation, helplessness/hopelessness, and quality of life. Psychological morbidity mediated the relationship between helplessness/hopelessness and quality of life. Therefore, even in the follow-up phase, it is important that health professionals are aware of the patient's emotional distress and body image to identify those at a higher risk of having a poorer quality of life.

  1. The p53 tumor suppressor-like protein nvp63 mediates selective germ cell death in the sea anemone Nematostella vectensis.

    Directory of Open Access Journals (Sweden)

    Sandra Pankow

    Full Text Available Here we report the identification and molecular function of the p53 tumor suppressor-like protein nvp63 in a non-bilaterian animal, the starlet sea anemone Nematostella vectensis. So far, p53-like proteins had been found in bilaterians only. The evolutionary origin of p53-like proteins is highly disputed and primordial p53-like proteins are variably thought to protect somatic cells from genotoxic stress. Here we show that ultraviolet (UV irradiation at low levels selectively induces programmed cell death in early gametes but not somatic cells of adult N. vectensis polyps. We demonstrate with RNA interference that nvp63 mediates this cell death in vivo. Nvp63 is the most archaic member of three p53-like proteins found in N. vectensis and in congruence with all known p53-like proteins, nvp63 binds to the vertebrate p53 DNA recognition sequence and activates target gene transcription in vitro. A transactivation inhibitory domain at its C-terminus with high homology to the vertebrate p63 may regulate nvp63 on a molecular level. The genotoxic stress induced and nvp63 mediated apoptosis in N. vectensis gametes reveals an evolutionary ancient germ cell protective pathway which relies on p63-like proteins and is conserved from cnidarians to vertebrates.

  2. Right frontal lobe mediation of recollection- and familiarity-based verbal recognition memory: evidence from patients with tumor resections.

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    Anderson, Nicole D; Davidson, Patrick S R; Mason, Warren P; Gao, Fuqiang; Binns, Malcolm A; Winocur, Gordon

    2011-12-01

    Medial-temporal, parietal, and pFC regions have been implicated in recollection and familiarity, but existing evidence from neuroimaging and patient studies is limited and conflicting regarding the role of specific regions within pFC in these memory processes. We report a study of 20 patients who had undergone resection of right frontal lobe tumors and 20 matched healthy control participants. The location and extent of lesions were traced on the patients' scans. A process dissociation procedure was employed to yield estimates of the contributions of recollection and familiarity in verbal recognition performance. Group comparisons revealed deficits in recollection but not familiarity in the patient group relative to their healthy counterparts. We found a positive relationship between estimates of familiarity and lesion sizes in the right inferior pFC (BA 11, 47) which was significant upon bootstrap resampling. These results are discussed in terms of prior work linking this area to an overextended sense of familiarity.

  3. CD133/Src axis mediates tumor initiating property and epithelial-mesenchymal transition of head and neck cancer.

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    Yu-Syuan Chen

    Full Text Available BACKGROUND: Head and Neck squamous cell carcinoma (HNSCC is a human lethal cancer with clinical, pathological, phenotypical and biological heterogeneity. Caner initiating cells (CICs, which are responsible for tumor growth and coupled with gain of epithelial-mesenchymal transition (EMT, have been identified. Previously, we enriched a subpopulation of head and neck cancer initiating cells (HN-CICs with up-regulation of CD133 and enhancement of EMT. Others demonstrate that Src kinase interacts with and phosphorylates the cytoplasmic domain of CD133. However, the physiological function of CD133/Src signaling in HNSCCs has not been uncovered. METHODOLOGY/PRINCIPAL FINDING: Herein, we determined the critical role of CD133/Src axis modulating stemness, EMT and tumorigenicity of HNSCC and HN-CICs. Initially, down-regulation of CD133 significantly reduced the self-renewal ability and expression of stemness genes, and promoted the differentiation and apoptotic capability of HN-CICs. Additionally, knockdown of CD133 in HN-CICs also lessened both in vitro malignant properties including cell migration/cell invasiveness/anchorage independent growth, and in vivo tumor growth by nude mice xenotransplantation assay. In opposite, overexpression of CD133 enhanced the stemness properties and tumorigenic ability of HNSCCs. Lastly, up-regulation of CD133 increased phosphorylation of Src coupled with EMT transformation in HNSCCs, on the contrary, silence of CD133 or treatment of Src inhibitor inversely abrogated above phenotypic effects, which were induced by CD133 up-regulation in HNSCCs or HN-CICs. CONCLUSION/SIGNIFICANCE: Our results suggested that CD133/Src signaling is a regulatory switch to gain of EMT and of stemness properties in HNSCC. Finally, CD133/Src axis might be a potential therapeutic target for HNSCC by eliminating HN-CICs.

  4. Sorafenib inhibits tumor growth and vascularization of rhabdomyosarcoma cells by blocking IGF-1R-mediated signaling

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    Wessen Maruwge

    2008-11-01

    Full Text Available Wessen Maruwge1, Pádraig D’Arcy1, Annika Folin1,2, Slavica Brnjic1, Johan Wejde1, Anthony Davis1, Fredrik Erlandsson3, Jonas Bergh1,2, Bertha Brodin11Department of Oncology and Pathology, Karolinska Institutet, Stockholm, Sweden; 2Radiumhemmet, Karolinska University Hospital, Stockholm, Sweden; 3Bayer Pharmaceutical Corporation, SwedenAbstract: The growth of many soft tissue sarcomas is dependent on aberrant growth factor signaling, which promotes their proliferation and motility. With this in mind, we evaluated the effect of sorafenib, a receptor tyrosine kinase inhibitor, on cell growth and apoptosis in sarcoma cell lines of various histological subtypes. We found that sorafenib effectively inhibited cell proliferation in rhabdomyosarcoma, synovial sarcoma and Ewing’s sarcoma with IC50 values <5 µM. Sorafenib effectively induced growth arrest in rhabdomyosarcoma cells, which was concurrent with inhibition of Akt and Erk signaling. Studies of ligand-induced phosphorylation of Erk and Akt in rhabdomyosarcoma cells showed that insulin-like growth factor-1 is a potent activator, which can be blocked by treatment with sorafenib. In vivo sorafenib treatment of rhabdomyosarcoma xenografts had a significant inhibitory effect on tumor growth, which was associated with inhibited vascularization and enhanced necrosis in the adjacent tumor stroma. Our results demonstrate that in vitro and in vivo growth of rhabdomyosarcoma can be suppressed by treatment with sorafenib, and suggests the possibilities of using sorafenib as a potential adjuvant therapy for the treatment of rhabdomyosarcoma.Keywords: soft tissue sarcoma, kinase inhibitors, targeted therapy, vascularization

  5. KLF4 regulates adult lung tumor-initiating cells and represses K-Ras-mediated lung cancer.

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    Yu, T; Chen, X; Zhang, W; Liu, J; Avdiushko, R; Napier, D L; Liu, A X; Neltner, J M; Wang, C; Cohen, D; Liu, C

    2016-02-01

    Lung cancer is the leading cause of cancer-related mortality in both men and women worldwide. To identify novel factors that contribute to lung cancer pathogenesis, we analyzed a lung cancer database from The Cancer Genome Atlas and found that Krüppel-like Factor 4 (KLF4) expression is significantly lower in patients' lung cancer tissue than in normal lung tissue. In addition, we identified seven missense mutations in the KLF4 gene. KLF4 is a transcription factor that regulates cell proliferation and differentiation as well as the self-renewal of stem cells. To understand the role of KLF4 in the lung, we generated a tamoxifen-induced Klf4 knockout mouse model. We found that KLF4 inhibits lung cancer cell growth and that depletion of Klf4 altered the differentiation pattern in the developing lung. To understand how KLF4 functions during lung tumorigenesis, we generated the K-ras(LSL-G12D/+);Klf4(fl/fl) mouse model, and we used adenovirus-expressed Cre to induce K-ras activation and Klf4 depletion in the lung. Although Klf4 deletion alone or K-ras mutation alone can trigger lung tumor formation, Klf4 deletion combined with K-ras mutation significantly enhanced lung tumor formation. We also found that Klf4 deletion in conjunction with K-ras activation caused lung inflammation. To understand the mechanism whereby KLF4 is regulated during lung tumorigenesis, we analyzed KLF4 promoter methylation and the profiles of epigenetic factors. We found that Class I histone deacetylases (HDACs) are overexpressed in lung cancer and that HDAC inhibitors induced expression of KLF4 and inhibited proliferation of lung cancer cells, suggesting that KLF4 is probably repressed by histone acetylation and that HDACs are valuable drug targets for lung cancer treatment.

  6. Analyses of CD20 Monoclonal Antibody–Mediated Tumor Cell Killing Mechanisms: Rational Design of Dosing Strategies

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    Lindorfer, Margaret A.

    2014-01-01

    Since approval of rituximab for treatment of B cell non-Hodgkin lymphoma, development of monoclonal antibodies (mAbs) for cancer treatment and elucidation of their cytotoxic mechanisms have been subject to intense investigations. Compelling evidence indicates that rituximab and another CD20 mAb, ofatumumab, must use the body’s cellular and humoral immune effector functions to kill malignant cells. Other U.S. Food and Drug Administration–approved mAbs, including obinutuzumab, cetuximab, and trastuzumab, require, in part, these effector mechanisms to eliminate tumor cells. Although gram quantities of mAbs can be administered to patients, our investigations of CD20 mAb-based therapies for chronic lymphocytic leukemia (CLL), including correlative measurements in clinical trials and studies with primary cells and cell lines, indicate that effector mechanisms necessary for mAb activity can be saturated or exhausted if tumor burdens are high, thus substantially compromising the efficacy of high-dose mAb therapy. Under these conditions, another reaction (trogocytosis) predominates in which bound CD20 mAb and CD20 are removed from targeted cells by effector cells that express Fcγ receptors, thereby allowing malignant cells to escape unharmed and continue to promote disease pathology. To address this problem, we propose that a low-dose strategy, based on administering 30–50 mg of CD20 mAb three times per week, may be far more effective for CLL than standard dosing because it will minimize effector function saturation and reduce trogocytosis. This approach may have general applicability to other mAbs that use immune effector functions, and could be formulated into a subcutaneous treatment strategy that would be more accessible and possibly more efficacious for patients. PMID:24944188

  7. Peroxisome-proliferator-activated receptors γ and β/δ mediate vascular endothelial growth factor production in colorectal tumor cells.

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    Röhrl, Clemens; Kaindl, Ulrike; Koneczny, Inga; Hudec, Xenia; Baron, David M; König, Jürgen S; Marian, Brigitte

    2011-01-01

    Peroxisome-proliferator-activated receptors (PPARs) are nuclear receptors for fatty acids and their derivatives. PPAR subtypes PPARγ and PPARβ/δ are suspected to modulate cancer development in the colon, but their exact role is still discussed controversially. The present study investigated the impact of PPARγ and PPARβ/δ on vascular endothelial growth factor (VEGF) and cyclooxygenase 2 (COX-2) expressions induced by synthetic and physiological agonists in the colorectal tumor cell lines SW480 and HT29 using reporter gene assays, qRT-PCR and ELISA. Activation of both PPARγ and PPARβ/δ induced expression of VEGF mRNA and protein in a PPAR-dependent way. The PPARγ agonists ciglitazone and PGJ(2) were the most effective inducers with up to ninefold and threefold increases in VEGF mRNA in SW480 and HT29 cultures, respectively. VEGF secretion was doubled in both cell lines. The PPARβ/δ agonists GW501516 and PGI(2) caused stimulations of only 1.5-fold in both cell lines. In addition, all PPAR agonists induced COX-2 mRNA and secretion of the COX-2 product PGE(2) in HT29 cells. However, this effect was not blocked by knock-down of PPAR expression nor was it essential for VEGF expression as shown by the lack of effect of the COX-2 inhibitor SC236. In summary, our results identify both PPARγ and PPARβ/δ as an alternative COX-independent mechanism of VEGF induction in colorectal tumor cells.

  8. Drosophila caliban, a nuclear export mediator, can function as a tumor suppressor in human lung cancer cells.

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    Bi, Xiaolin; Jones, Tamara; Abbasi, Fatima; Lee, Heuijung; Stultz, Brian; Hursh, Deborah A; Mortin, Mark A

    2005-12-15

    We previously showed that the Drosophila DNA binding homeodomain of Prospero included a 28 amino-acid sequence (HDA) that functions as a nuclear export signal. We describe here the identification of a protein we named Caliban, which can directly interact with the HDA. Caliban is homologous to human Sdccag1, which has been implicated in colon and lung cancer. Here we show that Caliban and Sdccag1 are mediators of nuclear export in fly and human cells, as interference RNA abrogates export of EYFP-HDA in normal fly and human lung cells. Caliban functions as a bipartite mediator nuclear export as the carboxy terminus binds HDA and the amino terminus itself functions as an NES, which directly binds the NES receptor Exportin. Finally, while non-cancerous lung cells have functional Sdccag1, five human lung carcinoma cell lines do not, even though Exportin still functions in these cells. Expression of fly Caliban in these human lung cancer cells restores EYFP-HDA nuclear export, reduces a cell's ability to form colonies on soft agar and reduces cell invasiveness. We suggest that Sdccag1 inactivation contributes to the transformed state of human lung cancer cells and that Caliban should be considered a candidate for use in lung cancer gene therapy.

  9. Cellular mechanisms mediating the stimulation of ovine endometrial secretion of prostaglandin F2 alpha in response to oxytocin: role of phospholipase A2.

    Science.gov (United States)

    Lee, J S; Silvia, W J

    1994-06-01

    Four experiments were conducted to determine whether phospholipase (PL) A2 mediates the stimulatory effect of oxytocin on the release of prostaglandin (PG) F2 alpha from ovine endometrial tissue. Caruncular endometrial tissue was collected from ovariectomized ewes on the day after a steroid replacement protocol had been completed. The replacement protocol consisted of progesterone for 10 days (12 mg/day) followed by oestradiol on days 10 and 11 (100 micrograms/day) and had been shown previously to provide endometrial tissue that would release PGF2 alpha in response to oxytocin in vitro. In experiment 1, oxytocin (10(-7) M) and melittin (1.76 x 10(-6) M; a stimulator of PLA2) stimulated release of PGF2 alpha from tissue explants (P 80% (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

  10. Cohesin Rad21 Mediates Loss of Heterozygosity and Is Upregulated via Wnt Promoting Transcriptional Dysregulation in Gastrointestinal Tumors

    Directory of Open Access Journals (Sweden)

    Huiling Xu

    2014-12-01

    Full Text Available Loss of heterozygosity (LOH of the adenomatous polyposis coli (APC gene triggers a series of molecular events leading to intestinal adenomagenesis. Haploinsufficiency of the cohesin Rad21 influences multiple initiating events in colorectal cancer (CRC. We identify Rad21 as a gatekeeper of LOH and a β-catenin target gene and provide evidence that Wnt pathway activation drives RAD21 expression in human CRC. Genome-wide analyses identified Rad21 as a key transcriptional regulator of critical CRC genes and long interspersed element (LINE-1 or L1 retrotransposons. Elevated RAD21 expression tracks with reactivation of L1 expression in human sporadic CRC, implicating cohesin-mediated L1 expression in global genomic instability and gene dysregulation in cancer.

  11. Highly sensitive proximity mediated immunoassay reveals HER2 status conversion in the circulating tumor cells of metastatic breast cancer patients

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    Kim Phillip

    2011-12-01

    Full Text Available Abstract Background The clinical benefits associated with targeted oncology agents are generally limited to subsets of patients. Even with favorable biomarker profiles, many patients do not respond or acquire resistance. Existing technologies are ineffective for treatment monitoring as they provide only static and limited information and require substantial amounts of tissue. Therefore, there is an urgent need to develop methods that can profile potential therapeutic targets with limited clinical specimens during the course of treatment. Methods We have developed a novel proteomics-based assay, Collaborative Enzyme Enhanced Reactive-immunoassay (CEER that can be used for analyzing clinical samples. CEER utilizes the formation of unique immuno-complex between capture-antibodies and two additional detector-Abs on a microarray surface. One of the detector-Abs is conjugated to glucose oxidase (GO, and the other is conjugated to Horse Radish Peroxidase (HRP. Target detection requires the presence of both detector-Abs because the enzyme channeling event between GO and HRP will not occur unless both Abs are in close proximity. Results CEER was able to detect single-cell level expression and phosphorylation of human epidermal growth factor receptor 2 (HER2 and human epidermal growth factor receptor 1 (HER1 in breast cancer (BCa systems. The shift in phosphorylation profiles of receptor tyrosine kinases (RTKs and other signal transduction proteins upon differential ligand stimulation further demonstrated extreme assay specificity in a multiplexed array format. HER2 analysis by CEER in 227 BCa tissues showed superior accuracy when compared to the outcome from immunohistochemistry (IHC (83% vs. 96%. A significant incidence of HER2 status alteration with recurrent disease was observed via circulating tumor cell (CTC analysis, suggesting an evolving and dynamic disease progression. HER2-positive CTCs were found in 41% (7/17 while CTCs with significant HER2

  12. Catch and Release of Cytokines Mediated by Tumor Phosphatidylserine Converts Transient Exposure into Long-Lived Inflammation.

    Science.gov (United States)

    Oyler-Yaniv, Jennifer; Oyler-Yaniv, Alon; Shakiba, Mojdeh; Min, Nina K; Chen, Ying-Han; Cheng, Sheue-Yann; Krichevsky, Oleg; Altan-Bonnet, Nihal; Altan-Bonnet, Grégoire

    2017-06-01

    Immune cells constantly survey the host for pathogens or tumors and secrete cytokines to alert surrounding cells of these threats. In vivo, activated immune cells secrete cytokines for several hours, yet an acute immune reaction occurs over days. Given these divergent timescales, we addressed how cytokine-responsive cells translate brief cytokine exposure into phenotypic changes that persist over long timescales. We studied melanoma cell responses to transient exposure to the cytokine interferon γ (IFNγ) by combining a systems-scale analysis of gene expression dynamics with computational modeling and experiments. We discovered that IFNγ is captured by phosphatidylserine (PS) on the surface of viable cells both in vitro and in vivo then slowly released to drive long-term transcription of cytokine-response genes. This mechanism introduces an additional function for PS in dynamically regulating inflammation across diverse cancer and primary cell types and has potential to usher in new immunotherapies targeting PS and inflammatory pathways. Published by Elsevier Inc.

  13. Genetic vaccination against the melanocyte lineage-specific antigen gp100 induces cytotoxic T lymphocyte-mediated tumor protection.

    Science.gov (United States)

    Schreurs, M W; de Boer, A J; Figdor, C G; Adema, G J

    1998-06-15

    Melanocyte lineage-specific antigens, such as gp100, have been shown to induce both cellular and humoral immune responses against melanoma. Therefore, these antigens are potential targets for specific antimelanoma immunotherapy. A novel approach to induce both cellular and humoral immunity is genetic vaccination, the injection of antigen-encoding naked plasmid DNA. In a mouse model, we investigated whether genetic vaccination against the human gp100 antigen results in specific antitumor immunity. The results demonstrate that vaccinated mice were protected against a lethal challenge with syngeneic B16 melanoma-expressing human gp100, but not control-transfected B16. Both cytotoxic T cells and IgG specific for human gp100 could be detected in human gp100-vaccinated mice. However, only adoptive transfer of spleen-derived lymphocytes, not of the serum, isolated from protected mice was able to transfer antitumor immunity to nonvaccinated recipients, indicating that CTLs are the predominant effector cells. CTI, lines generated from human gp100-vaccinated mice specifically recognized human gp100. Interestingly, one of the CTL lines cross-reacted between human and mouse gp100, indicating the recognition of a conserved epitope. However, these CTLs did not appear to be involved in the observed tumor protection. Collectively, our results indicate that genetic vaccination can result in a potent antitumor response in vivo and constitutes a potential immunotherapeutic strategy to fight cancer.

  14. Impaired Th1 immunity in ovarian cancer patients is mediated by TNFR2+ Tregs within the tumor microenvironment.

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    Govindaraj, Chindu; Scalzo-Inguanti, Karen; Madondo, Mutsa; Hallo, Julene; Flanagan, Katie; Quinn, Michael; Plebanski, Magdalena

    2013-10-01

    Ovarian cancer is a prevalent gynecological malignancy with potent immune-suppression capabilities; regulatory T cells (Tregs) are significant contributors to this immune-suppression. As ovarian cancer patients present with high levels of TNF and Tregs expressing TNFR2 are associated with maximal suppressive capacity, we investigated TNFR2+ Tregs within these patients. Indeed, TNFR2+ Tregs from tumor-associated ascites were the most potent suppressor T cell fraction. They were abundantly present within the ascites and more suppressive than peripheral blood TNFR2+ Tregs in patients. The increased suppressive capacity can be explained by a distinct cell surface expression profile, which includes high levels of CD39, CD73, TGF-β and GARP. Additionally, CD73 expression level on TNFR2+ Tregs was inversely correlated with IFN-γ production by effector T cells. This Treg fraction can be selectively recruited into the ascites from the peripheral blood of patients. Targeting TNFR2+ Tregs may offer new approaches to enhance the poor survival rates of ovarian cancer.

  15. The growth and tumor suppressors NORE1A and RASSF1A are targets for calpain-mediated proteolysis.

    Directory of Open Access Journals (Sweden)

    Sergey Kuznetsov

    Full Text Available BACKGROUND: NORE1A and RASSF1A are growth and tumour suppressors inactivated in a variety of cancers. Methylation of NORE1A and RASSF1A promoters is the predominant mechanism for downregulation of these proteins; however, other mechanisms are likely to exist. METHODOLOGY/PRINCIPAL FINDINGS: Here we describe a proteolysis of NORE1A and RASSF1A by calpains as alternative mechanism of their downregulation. Extracts of H358 cell line, a human bronchoalveolar carcinoma, and H460, a large cell carcinoma, were capable of proteolysis of NORE1A protein in the calpain-dependent manner. Likewise, RASSF1A tumor suppressor was proteolyzed by the H358 cell extract. Addition of calpain inhibitor to H358 and H460 cells growing in tissue culture resulted in re-expression of endogenous NORE1A. A survey of 10 human lung tumours revealed that three of them contain an activity capable of inducing NORE1A degradation. CONCLUSIONS/SIGNIFICANCE: Thus, degradation by calpains is a novel mechanism for downregulation of NORE1A and RASSF1A proteins and might be the mechanism allowing cancer cells to escape growth suppression.

  16. Expression proteomics of UPF1 knockdown in HeLa cells reveals autoregulation of hnRNP A2/B1 mediated by alternative splicing resulting in nonsense-mediated mRNA decay

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    Zavolan Mihaela

    2010-10-01

    Full Text Available Abstract Background In addition to acting as an RNA quality control pathway, nonsense-mediated mRNA decay (NMD plays roles in regulating normal gene expression. In particular, the extent to which alternative splicing is coupled to NMD and the roles of NMD in regulating uORF containing transcripts have been a matter of debate. Results In order to achieve a greater understanding of NMD regulated gene expression we used 2D-DiGE proteomics technology to examine the changes in protein expression induced in HeLa cells by UPF1 knockdown. QPCR based validation of the corresponding mRNAs, in response to both UPF1 knockdown and cycloheximide treatment, identified 17 bona fide NMD targets. Most of these were associated with bioinformatically predicted NMD activating features, predominantly upstream open reading frames (uORFs. Strikingly, however, the majority of transcripts up-regulated by UPF1 knockdown were either insensitive to, or even down-regulated by, cycloheximide treatment. Furthermore, the mRNA abundance of several down-regulated proteins failed to change upon UPF1 knockdown, indicating that UPF1's role in regulating mRNA and protein abundance is more complex than previously appreciated. Among the bona fide NMD targets, we identified a highly conserved AS-NMD event within the 3' UTR of the HNRNPA2B1 gene. Overexpression of GFP tagged hnRNP A2 resulted in a decrease in endogenous hnRNP A2 and B1 mRNA with a concurrent increase in the NMD sensitive isoforms. Conclusions Despite the large number of changes in protein expression upon UPF1 knockdown, a relatively small fraction of them can be directly attributed to the action of NMD on the corresponding mRNA. From amongst these we have identified a conserved AS-NMD event within HNRNPA2B1 that appears to mediate autoregulation of HNRNPA2B1 expression levels.

  17. The mediation of the central histaminergic system in the pressor effect of intracerebroventricularly injected melittin, a phospholipase A2 activator, in normotensive rats.

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    Altinbas, Burcin; Topuz, Bora B; Yilmaz, Mustafa S; Aydin, Cenk; Savci, Vahide; Jochem, Jerzy; Aydin, Sami; Yalcin, Murat

    2012-01-01

    Melittin is a polypeptide component of bee venom that leads to an increase in arachidonic acid release and subsequently in prostaglandin synthesis by activating phospholipase A(2). Recently we demonstrated that centrally or peripherally administrated melittin caused pressor effect and central thromboxane A(2) (TXA(2)) and cholinergic system mediated these effects of melittin. Also centrally injected histamine leads to pressor and bradycardic response by activating central histamine receptors in normotensive rats and central cholinergic system involved the effects of histamine. The present study demonstrates an involvement of the central histaminergic system in melittin-induced cardiovascular effect in normotensive rats. Experiments were carried out in male Sprague Dawley rats. Intracerebroventricularly (i.c.v.) injected melittin (0.5, 1 and 2 nmol) caused dose- and time-dependent increases in mean arterial pressure (MAP) and decrease in heart rate (HR) as we reported previously. Moreover, H(2) receptor antagonist ranitidine (50 nmol; i.c.v.) almost completely and H(3)/H(4) receptor antagonist thioperamide (50 nmol; i.c.v.) partly blocked melittin-evoked cardiovascular effects, whereas H(1) receptor blocker chlorpheniramine (50 nmol; i.c.v.) had no effect. Also centrally injected melittin was accompanied by 28% increase in extracellular histamine concentration in the posterior hypothalamus, as shown in microdialysis studies. In conclusion, results show that centrally administered melittin causes pressor and bradycardic response in conscious rats. Moreover, according to our findings, there is an involvement of the central histaminergic system in melittin-induced cardiovascular effects.

  18. RNAseq Analyses Identify Tumor Necrosis Factor-Mediated Inflammation as a Major Abnormality in ALS Spinal Cord.

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    Brohawn, David G; O'Brien, Laura C; Bennett, James P

    2016-01-01

    ALS is a rapidly progressive, devastating neurodegenerative illness of adults that produces disabling weakness and spasticity arising from death of lower and upper motor neurons. No meaningful therapies exist to slow ALS progression, and molecular insights into pathogenesis and progression are sorely needed. In that context, we used high-depth, next generation RNA sequencing (RNAseq, Illumina) to define gene network abnormalities in RNA samples depleted of rRNA and isolated from cervical spinal cord sections of 7 ALS and 8 CTL samples. We aligned >50 million 2X150 bp paired-end sequences/sample to the hg19 human genome and applied three different algorithms (Cuffdiff2, DEseq2, EdgeR) for identification of differentially expressed genes (DEG's). Ingenuity Pathways Analysis (IPA) and Weighted Gene Co-expression Network Analysis (WGCNA) identified inflammatory processes as significantly elevated in our ALS samples, with tumor necrosis factor (TNF) found to be a major pathway regulator (IPA) and TNFα-induced protein 2 (TNFAIP2) as a major network "hub" gene (WGCNA). Using the oPOSSUM algorithm, we analyzed transcription factors (TF) controlling expression of the nine DEG/hub genes in the ALS samples and identified TF's involved in inflammation (NFkB, REL, NFkB1) and macrophage function (NR1H2::RXRA heterodimer). Transient expression in human iPSC-derived motor neurons of TNFAIP2 (also a DEG identified by all three algorithms) reduced cell viability and induced caspase 3/7 activation. Using high-density RNAseq, multiple algorithms for DEG identification, and an unsupervised gene co-expression network approach, we identified significant elevation of inflammatory processes in ALS spinal cord with TNF as a major regulatory molecule. Overexpression of the DEG TNFAIP2 in human motor neurons, the population most vulnerable to die in ALS, increased cell death and caspase 3/7 activation. We propose that therapies targeted to reduce inflammatory TNFα signaling may be helpful

  19. Tumor necrosis factor alpha production from CD8+ T cells mediates oviduct pathological sequelae following primary genital Chlamydia muridarum infection.

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    Murthy, Ashlesh K; Li, Weidang; Chaganty, Bharat K R; Kamalakaran, Sangamithra; Guentzel, M Neal; Seshu, J; Forsthuber, Thomas G; Zhong, Guangming; Arulanandam, Bernard P

    2011-07-01

    The immunopathogenesis of Chlamydia trachomatis-induced oviduct pathological sequelae is not well understood. Mice genetically deficient in perforin (perforin(-/-) mice) or tumor necrosis factor alpha (TNF-α) production (TNF-α(-/-) mice) displayed comparable vaginal chlamydial clearance rates but significantly reduced oviduct pathology (hydrosalpinx) compared to that of wild-type mice. Since both perforin and TNF-α are effector mechanisms of CD8(+) T cells, we evaluated the role of CD8(+) T cells during genital Chlamydia muridarum infection and oviduct sequelae. Following vaginal chlamydial challenge, (i) mice deficient in TAP I (and therefore the major histocompatibility complex [MHC] I pathway and CD8(+) T cells), (ii) wild-type mice depleted of CD8(+) T cells, and (iii) mice genetically deficient in CD8 (CD8(-/-) mice) all displayed similar levels of vaginal chlamydial clearance but significantly reduced hydrosalpinx, compared to those of wild-type C57BL/6 mice, suggesting a role for CD8(+) T cells in chlamydial pathogenesis. Repletion of CD8(-/-) mice with wild-type or perforin(-/-), but not TNF-α(-/-), CD8(+) T cells at the time of challenge restored hydrosalpinx to levels observed in wild-type C57BL/6 mice, suggesting that TNF-α production from CD8(+) T cells is important for pathogenesis. Additionally, repletion of TNF-α(-/-) mice with TNF-α(+/+) CD8(+) T cells significantly enhanced the incidence of hydrosalpinx and oviduct dilatation compared to those of TNF-α(-/-) mice but not to the levels found in wild-type mice, suggesting that TNF-α production from CD8(+) T cells and non-CD8(+) cells cooperates to induce optimal oviduct pathology following genital chlamydial infection. These results provide compelling new evidence supporting the contribution of CD8(+) T cells and TNF-α production to Chlamydia-induced reproductive tract sequelae.

  20. Transferrin-PEG-PE modified dexamethasone conjugated cationic lipid carrier mediated gene delivery system for tumor-targeted transfection

    Science.gov (United States)

    Wang, Wei; Zhou, Fang; Ge, Linfu; Liu, Ximin; Kong, Fansheng

    2012-01-01

    Background The main barriers to non-viral gene delivery include cellular and nuclear membranes. As such, the aim of this study was to develop a type of vector that can target cells through receptor-mediated pathways and by using nuclear localization signal (NLS) to increase the nuclear uptake of genetic materials. Methods A dexamethasone (Dexa)-conjugated lipid was synthesized as the material of the solid lipid nanoparticles (SLNs), and transferrin (Tf) was linked onto polyethylene glycol-phosphatidylethanolamine (PEG-PE) to obtain Tf-PEG-PE ligands for the surface modification of the carriers. The in vitro transfection efficiency of the novel modified vectors was evaluated in human hepatoma carcinoma cell lines, and in vivo effects were observed in an animal model. Results Tf-PEG-PE modified SLNs/enhanced green fluorescence protein plasmid (pEGFP) had a particle size of 222 nm and a gene loading quantity of 90%. Tf-PEG-PE-modified SLNs/pEGFP (Tf-SLNs/pEGFP) displayed remarkably higher transfection efficiency than non-modified SLNs/pEGFP and the vectors not containing Dexa, both in vitro and in vivo. Conclusion It can be concluded that Tf and Dexa could function as an excellent active targeting ligand to improve the cell targeting and nuclear targeting ability of the carriers, and the resulting nanomedicine could be a promising active targeting drug/gene delivery system. PMID:22679364

  1. Dpy-19 like 3-mediated C-mannosylation and expression levels of RPE-spondin in human tumor cell lines.

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    Morishita, Shohei; Suzuki, Takehiro; Niwa, Yuki; Dohmae, Naoshi; Simizu, Siro

    2017-08-01

    C-mannosylation is a unique type of protein glycosylation with a mannose attached to the tryptophan residue via the C-C linkage. Our previous study revealed that dpy-19 like 3 (DPY19L3) acts as a C-mannosyltransferase in human cells. The present study hypothesized that RPE-spondin (RPESP) may be a substrate protein of DPY19L3-mediated C-mannosylation. RPESP has unknown biological functions and has two putative C-mannosylation sites at the W(80) and W(83) residues; however, to the best of our knowledge, C-mannosylation of RPESP has not previously been investigated. The present study suggested that RPESP is C-mannosylated at W(80) and W(83) in human cells, whereas gain-of-function experiments using S2 cells revealed that human DPY19L3 catalyzed the C-mannosylation of RPESP at W(83) but not W(80), which suggested substrate specificity. In addition, the present study detected mRNA expression levels of RPESP in various types of cancer cell lines and high expression levels of RPESP were revealed in certain colorectal cancer cell lines, suggesting that RPESP may have an association with the malignancy of colorectal cancers.

  2. Oct4 mediates tumor initiating properties in oral squamous cell carcinomas through the regulation of epithelial-mesenchymal transition.

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    Lo-Lin Tsai

    Full Text Available BACKGROUND: Overexpression of Oct4, an important transcription factor of embryonic stem cells (ESC, has been reported in several cancers. The aim of this study was to determine the emerging role of Oct4 in oral squamous cell carcinoma (OSCC both in vitro and in vivo. METHODOLOGY/PRINCIPAL FINDING: Tumourigenic activity and molecular mechanisms of Oct4 overexpression or knockdown by lentiviral infection in OSCC was investigated in vitro and in vivo. Initially, we demonstrated that Oct4 expression was increased in OSCC cell lines as compared to a normal oral epithelial cell line SG. Overexpression of Oct4 was demonstrated to enhance cell proliferation, invasiveness, anchorage-independent growth and xenotransplantation tumourigenicity. These findings were coupled with epithelial-mesenchymal transition (EMT transformation in OSCCs. In contrast, the silence of Oct4 significantly blocked the xenograft tumorigenesis of OSCC-derived cancer stem cells (OSCC-CSCs and significantly improved the recipient survival. Clinically, the level of Oct4 expression was higher in recurrent and metastatic OSCC specimens but lower in primary OSCC specimens. CONCLUSION/SIGNIFICANCE: Our results suggest that Oct4-mediated tumorigenecity is associated with the regulation of EMT. Oct4 might be a therapeutic target for OSCC.

  3. Treatment of therapy-resistant perineal metastatic Crohn's disease after proctectomy using anti-tumor necrosis factor chimeric monoclonal antibody, cA2 - Report of two cases

    NARCIS (Netherlands)

    van Dullemen, HM; de Jong, E; Slors, F; Tytgat, GNJ; van Denventer, SJH

    PURPOSE: Two young females with well-documented Crohn's disease and nonhealing perineal wounds following proctectomy compatible with "metastatic Crohn's disease" are described, We hypothesized that metastatic Crohn's disease would be a tumor necrosis factor-dependent inflammatory-reaction and have

  4. Mecp2-mediated Epigenetic Silencing of miR-137 Contributes to Colorectal Adenoma-Carcinoma Sequence and Tumor Progression via Relieving the Suppression of c-Met

    Science.gov (United States)

    Chen, Tao; Cai, Shi-Lun; Li, Jian; Qi, Zhi-Peng; Li, Xu-Quan; Ye, Le-Chi; Xie, Xiao-Feng; Hou, Ying-Yong; Yao, Li-Qing; Xu, Mei-Dong; Zhou, Ping-Hong; Xu, Jian-Min; Zhong, Yun-Shi

    2017-01-01

    The molecular mechanisms underlying colorectal cancer (CRC) development remain elusive. In this study, we examined the miRNA and mRNA expressions in the adenoma-carcinoma sequence (ACS), a critical neoplastic progression in CRC development. We found that miR-137 was down-regulated in all adenoma and carcinoma tissues. Low miR-137 levels were correlated negatively with tumor progression and metastasis. Then we identified the inhibition effect of the miR-137 in CRC development, both in CRC cell lines and mouse models. MiR-137 was shown to control CRC cell proliferation, colony formation, migration and invasion and to control tumor growth and metastasis. We further confirmed the negative association between miR-137 and c-Met expression and thus validated this important oncogene as the target of miR-137 in CRC. In addition, we found a DNA methyl-CpG-binding protein, Mecp2, was up-regulated in ACS tissues via mRNA sequencing. Further experiment showed that miR-137 expression in CRC was subjected to epigenetic regulation mediated by Mecp2. We also confirmed c-Met expression can be up-regulated by silencing of miR-137 and suppressed by coexpression of Mecp2 and miR-137. These findings highlight the critical role of miR-137-c-Met nexus in CRC development and reveal Mecp2-regulated epigenetic silence causes the downregulation of miR-137 in colorectal adenoma and carcinoma. PMID:28291253

  5. ENO1 promotes tumor proliferation and cell adhesion mediated drug resistance (CAM-DR) in Non-Hodgkin's Lymphomas

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    Zhu, Xinghua; Miao, Xiaobing; Wu, Yaxun; Li, Chunsun; Guo, Yan; Liu, Yushan; Chen, Yali; Lu, Xiaoyun [Department of Pathology, Affiliated Cancer Hospital of Nantong University, 30 North Tongyang Road, Pingchao, Nantong 226361, Jiangsu (China); Wang, Yuchan, E-mail: wangyuchannt@126.com [Department of Pathogen and Immunology, Medical College, Nantong University, 19 Qixiu Road, Nantong 226001, Jiangsu (China); He, Song, E-mail: hesongnt@126.com [Department of Pathology, Affiliated Cancer Hospital of Nantong University, 30 North Tongyang Road, Pingchao, Nantong 226361, Jiangsu (China)

    2015-07-15

    Enolases are glycolytic enzymes responsible for the ATP-generated conversion of 2-phosphoglycerate to phosphoenolpyruvate. In addition to the glycolytic function, Enolase 1 (ENO1) has been reported up-regulation in several tumor tissues. In this study, we investigated the expression and biologic function of ENO1 in Non-Hodgkin's Lymphomas (NHLs). Clinically, by western blot analysis we observed that ENO1 expression was apparently higher in diffuse large B-cell lymphoma than in the reactive lymphoid tissues. Subsequently, immunohistochemical staining of 144 NHLs suggested that the expression of ENO1 was significantly lower in the indolent lymphomas compared with the progressive lymphomas. Further, we identified ENO1 as an independent prognostic factor, and it was significantly correlated with overall survival of NHL patients. In addition, we found that ENO1 could promote cell proliferation, regulate cell cycle associated gene and PI3K/AKT signaling pathway in NHLs. Finally, we verified that ENO1 participated in the process of lymphoma cell adhesion mediated drug resistance (CAM-DR). Adhesion to FN or HS5 cells significantly protected OCI-Ly8 and Daudi cells from cytotoxicity compared with those cultured in suspension, and these effects were attenuated when transfected with ENO1-siRNA. Based on the study, we propose that inhibition of ENO1 expression may be a novel strategy for therapy for NHLs patients, and it may be a target for drug resistance. - Highlights: • ENO1 expression is reversely correlated with clinical outcomes of patients with NHLs. • ENO1 promotes the proliferation of NHL cells. • ENO1 regulates cell adhesion mediated drug resistance.

  6. Response to tumor necrosis factor-α mediated inflammation involving activation of prostaglandin E2 and Wnt signaling in nucleus pulposus cells.

    Science.gov (United States)

    Hiyama, Akihiko; Yokoyama, Katsuya; Nukaga, Tadashi; Sakai, Daisuke; Mochida, Joji

    2015-12-01

    The cyclooxygenase 2 (COX-2) product, prostaglandin E2 (PGE2 ), acts through a family of G protein-coupled receptors designated E-prostanoid (EP) receptors that mediate intracellular signaling by multiple pathways. However, it is not known whether crosstalk between tumor necrosis factor-α(TNF-α)-PGE2 -mediated signaling and Wnt signaling plays a role in the regulation of intervertebral disc (IVD) cells. In this study, we investigated the relationship between TNF-α-PGE2 signaling and Wnt signaling in IVD cells. TNF-α increased the expression of COX-2 in IVD cells. The EP receptors EP1, EP3, and EP4 were expressed in IVD cells, and TNF-α significantly increased PGE2 production. Stimulation with TNF-α also upregulated EP3 and EP4 mRNA and protein expression in IVD cells. The inductive effect of the EP3 and EP4 receptors on Topflash promoter activity was confirmed through gain- and loss-of-function studies using selective EP agonists and antagonists. PGE2 treatment activated Wnt-β-catenin signaling through activation of EP3. We conclude that TNF-α-induced COX-2 and PGE2 stimulate Wnt signaling and activate Wnt target genes. Suppression of the EP3 receptor via TNF-α-PGE2 signaling seems to suppress IVD degeneration by controlling the activation of Wnt signaling. These findings may help identify the underlying mechanism and role of Wnt signaling in IVD degeneration. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  7. Xenoestrogens at picomolar to nanomolar concentrations trigger membrane estrogen receptor-alpha-mediated Ca2+ fluxes and prolactin release in GH3/B6 pituitary tumor cells.

    Science.gov (United States)

    Wozniak, Ann L; Bulayeva, Nataliya N; Watson, Cheryl S

    2005-04-01

    Xenoestrogens (XEs) are widespread in our environment and are known to have deleterious effects in animal (and perhaps human) populations. Acting as inappropriate estrogens, XEs are thought to interfere with endogenous estrogens such as estradiol (E2) to disrupt normal estrogenic signaling. We investigated the effects of E2 versus several XEs representing organochlorine pesticides (dieldrin, endosulfan, o',p'-dichlorodiphenylethylene), plastics manufacturing by-products/detergents (nonylphenol, bisphenol A), a phytoestrogen (coumestrol), and a synthetic estrogen (diethylstilbestrol) on the pituitary tumor cell subline GH3/B6/F10, previously selected for expression of high levels of membrane estrogen receptor-alpha. Picomolar to nanomolar concentrations of both E2 and XEs caused intracellular Ca2+ changes within 30 sec of administration. Each XE produced a unique temporal pattern of Ca2+ elevation. Removing Ca2+ from the extracellular solution abolished both spontaneous and XE-induced intracellular Ca2+ changes, as did 10 microM nifedipine. This suggests that XEs mediate their actions via voltage-dependent L-type Ca2+ channels in the plasma membrane. None of the Ca2+ fluxes came from intracellular Ca2+ stores. E2 and each XE also caused unique time- and concentration-dependent patterns of prolactin (PRL) secretion that were largely complete within 3 min of administration. PRL secretion was also blocked by nifedipine, demonstrating a correlation between Ca2+ influx and PRL secretion. These data indicate that at very low concentrations, XEs mediate membrane-initiated intracellular CCa2+ increases resulting in PRL secretion via a mechanism similar to that for E2, but with distinct patterns and potencies that could explain their abilities to disrupt endocrine functions.

  8. Gene therapy for human nasopharyngeal carcinoma by adenovirus-mediated transfer of human p53, GM-CSF, and B7-1 genes in a mouse xenograft tumor model.

    Science.gov (United States)

    Ren, Su-Ping; Wang, Lan; Wang, Hua; Wu, Bin; Han, Ying; Wang, Li-Sheng; Wu, Chu-Tse

    2008-10-01

    Incidence of nasopharyngeal carcinoma (NPC) remains high in endemic regions. Prevention of tumor recurrences and metastases is a crucial approach to improve therapeutic outcome in NPC patients. In this study, we investigated the effects of the cotransfer of the tumor suppressor gene, p53, in combination with the immunostimulatory genes, GM-CSF and B7-1, on tumor regression and subsequent tumor recurrence. We constructed a recombinant adenovirus carrying human wild-type p53, granulocyte-macrophage colony-stimulating factor (GM-CSF), and B7-1 genes (Ad-p53/GM-CSF/B7-1), which mediated high-level expression of these three genes in NPC CNE-1 cells. Ad-p53/GM-CSF/B7-1 infection inhibited the growth of CNE-1 cells and induced tumor-specific cytotoxic T-lymphocytes (CTLs) in vitro. In CNE-1 xenograft tumor models in huPBL-nonobese diabetic/severe combined immunodeficiency (NOD/SCID) mice, an intratumoral injection of Ad-p53/GM-CSF/B7-1 resulted in a reduced tumor burden, compared to normal saline (NS) and Ad-p53 controls. Tumors in the Ad-p53/GM-CSF/B7-1 group displayed diffuse necrosis and infiltration of human T-cells. Further, the tumor occurrence of CNE-1 cell rechallenge largely decreased after the primary tumor was intratumorally injected with Ad-p53/GM-CSF/B7-1 in the HuPBL-NOD/SCID mice model. Only 2 of 8 (25%) animals in the Ad-p53/GM-CSF/B7-1 group had developed measurable tumors, which demonstrated extensive necrosis and much more human T-cell infiltration, compared to 5 of 7 (71%) in the NS and Ad-p53 groups. Therefore, the adenovirus-mediated introduction of p53, GM-CSF, and B7-1 genes could improve local control and prevent the recurrence or metastases of NPC tumors, which suggests a potential therapeutic value in NPC treatment.

  9. Quercetin enhances apoptotic effect of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) in ovarian cancer cells through reactive oxygen species (ROS) mediated CCAAT enhancer-binding protein homologous protein (CHOP)-death receptor 5 pathway

    Science.gov (United States)

    Yi, Liu; Zongyuan, Yang; Cheng, Gong; Lingyun, Zhang; GuiLian, Yu; Wei, Gong

    2014-01-01

    Although tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has shown efficacy in a phase 2 clinical trial, development of resistance to TRAIL by tumor cells is a major roadblock. We investigated whether quercetin, a flavonoid, can sensitize human ovarian cancer cells to TRAIL. Results indicate that quercetin sensitized cancer cells to TRAIL. The quercetin induced expression of death receptor DR5 but did not affect expression of DR4 in cancer cells. The induction of DR5 was mediated through activation of JNK and through upregulation of a transcription factor CCAAT enhancer-binding protein homologous protein (CHOP); as silencing of these signaling molecules abrogated the effect of quercetin. Upregulation of DR5 was mediated through the generation of reactive oxygen species (ROS), as ROS scavengers reduced the effect of quercetin on JNK activation, CHOP upregulation, DR induction, TRAIL sensitization, downregulated the expression of cell survival proteins and upregulated the proapoptotic proteins. Furthermore, quercetin enhances TRAIL mediated inhibition of tumor growth of human SKOV-3 xenograft was associated with induction of apoptosis, activation of caspase-3, CHOP and DR5. Overall, our data suggest that quercetin enhances apoptotic death of ovarian cancer cells to TRAIL through upregulation of CHOP-induced DR5 expression following ROS mediated endoplasmic reticulum-stress. PMID:24612139

  10. Extracellular signal-regulated kinase 2 (ERK-2) mediated phosphorylation regulates nucleo-cytoplasmic shuttling and cell growth control of Ras-associated tumor suppressor protein, RASSF2

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    Kumari, Gita [Laboratory of Molecular Virology, Centre for DNA Fingerprinting and Diagnostics, Hyderabad 500076 (India); Mahalingam, S., E-mail: mahalingam@iitm.ac.in [Laboratory of Molecular Virology, Centre for DNA Fingerprinting and Diagnostics, Hyderabad 500076 (India); Department of Biotechnology, Laboratory of Molecular Virology and Cell Biology, Indian Institute of Technology-Madras, Chennai 600 036 (India)

    2009-10-01

    Ras GTPase controls the normal cell growth through binding with an array of effector molecules, such as Raf and PI3-kinase in a GTP-dependent manner. RASSF2, a member of the Ras association domain family, is known to be involved in the suppression of cell growth and is frequently down-regulated in various tumor tissues by promoter hypermethylation. In the present study, we demonstrate that RASSF2 shuttles between nucleus and cytoplasm by a signal-mediated process and its export from the nucleus is sensitive to leptomycin B. Amino acids between 240 to 260 in the C-terminus of RASSF2 harbor a functional nuclear export signal (NES), which is necessary and sufficient for efficient export of RASSF2 from the nucleus. Substitution of conserved Ile254, Val257 and Leu259 within the minimal NES impaired RASSF2 export from the nucleus. In addition, wild type but not the nuclear export defective RASSF2 mutant interacts with export receptor, CRM-1 and exported from the nucleus. Surprisingly, we observed nucleolar localization for the nuclear export defective mutant suggesting the possibility that RASSF2 may localize in different cellular compartments transiently in a cell cycle dependent manner and the observed nuclear localization for wild type protein may be due to faster export kinetics from the nucleolus. Furthermore, our data suggest that RASSF2 is specifically phosphorylated by MAPK/ERK-2 and the inhibitors of MAPK pathway impair the phosphorylation and subsequently block the export of RASSF2 from the nucleus. These data clearly suggest that ERK-2 mediated phosphorylation plays an important role in regulating the nucleo-cytoplasmic shuttling of RASSF2. Interestingly, nuclear import defective mutant of RASSF2 failed to induce cell cycle arrest at G1/S phase and apoptosis suggesting that RASSF2 regulates cell growth in a nuclear localization dependent manner. Collectively, these data provided evidence for the first time that MAPK/ERK-2 mediated phosphorylation regulates

  11. HIV-1 Tat C-mediated regulation of tumor necrosis factor receptor-associated factor-3 by microRNA 32 in human microglia

    Directory of Open Access Journals (Sweden)

    Mishra Ritu

    2012-06-01

    Full Text Available Abstract Background HIV-1 Tat protein is known to be associated with neuroinflammation, a condition that develops in almost half of patients infected with HIV-1. HIV-1 Tat can alter glial neuroprotective functions, leading to neurotoxicity within the CNS. HIV-1 Tat is known to be secreted from productively infected cells and can affect neighboring uninfected cells by modulating cel