WorldWideScience

Sample records for a2 mediated tumor

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

    Directory of Open Access Journals (Sweden)

    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.

  2. 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.

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

    Directory of Open Access Journals (Sweden)

    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

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

    Science.gov (United States)

    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.

  5. KSHV-Mediated Angiogenesis in Tumor Progression

    Directory of Open Access Journals (Sweden)

    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.

  6. 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

  7. 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

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  10. Anti-EphA2 Antibodies Decrease EphA2 Protein Levels in Murine CT26 Colorectal and Human MDA-231 Breast Tumors But Do Not Inhibit Tumor Growth

    Directory of Open Access Journals (Sweden)

    David Kiewlich

    2006-01-01

    Full Text Available The EphA2 receptor tyrosine kinase has been shown to be over-expressed in cancer and a monoclonal antibody (mAb that activates and down-modulates EphA2 was reported to inhibit the growth of human breast and lung tumor xenografts in nude mice. Reduction of EphA2 levels by treatment with anti-EphA2 siRNA also inhibited tumor growth, suggesting that the anti-tumor effects of these agents are mediated by decreasing the levels of EphA2. As these studies employed human tumor xenograft models in nude mice with reagents whose crossreactivity with murine EphA2 is unknown, we generated a mAb (Ab20 that preferentially binds, activates, and induces the degradation of murine EphA2. Treatment of established murine CT26 colorectal tumors with Ab20 reduced EphA2 protein levels to ~12% of control tumor levels, yet had no effect on tumor growth. CT26 tumor cell colonization of the lung was also not affected by Ab20 administration despite having barely detectable levels of EphA2. We also generated and tested a potent agonistic mAb against human EphA2 (1G9-H7. No inhibition of human MDA-231 breast tumor xenograft growth was observed despite evidence for >85% reduction of EphA2 protein levels in the tumors. These results suggest that molecular characteristics of the tumors in addition to EphA2 over-expression may be important for predicting responsiveness to EphA2-directed therapies.

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

    Directory of Open Access Journals (Sweden)

    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

  12. Mediated coalescence: a possible mechanism for tumor cellular heterogeneity

    Science.gov (United States)

    Ambrose, Joseph; Livitz, Michelle; Wessels, Deborah; Kuhl, Spencer; Lusche, Daniel F; Scherer, Amanda; Voss, Edward; Soll, David R

    2015-01-01

    Recently, we demonstrated that tumorigenic cell lines and fresh tumor cells seeded in a 3D Matrigel model, first grow as clonal islands (primary aggregates), then coalesce through the formation and contraction of cellular cables. Non-tumorigenic cell lines and cells from normal tissue form clonal islands, but do not form cables or coalesce. Here we show that as little as 5% tumorigenic cells will actively mediate coalescence between primary aggregates of majority non-tumorigenic or non-cancerous cells, by forming cellular cables between them. We suggest that this newly discovered, specialized characteristic of tumorigenic cells may explain, at least in part, why tumors contain primarily non-tumorigenic cells. PMID:26807328

  13. The development of somatostatin analogues mediated tumor targeting and therapy

    International Nuclear Information System (INIS)

    Radionuclide labelled somatostatin analogues have been widely used in the detection of neuro-endocrine tumors. Till now, most of somatostatin analogues only have high affinity to somatostatin receptor 2 (SSTR2), further clinical applications was limitted. A new generation of somatostatin analogues such as 1, 4, 7, 10-tetraazacyclodocecane-N, N', N'', N''' -tetaraacetic acid-Na 13- octertide (DOTA-NOC) etc, binding to somatostatin receptors not only SSTR2 but other subtypes has been used mainly in preclinical study. In this review, we discussed these new somatostatin analogues, chelating agent, and their new labelled compounds, these new radionuclide labelled somatostatin analogues may hold great promise for the receptor-mediated tumor imaging and treatments. (authors)

  14. Capacity of tumor necrosis factor to augment lymphocyte-mediated tumor cell lysis of malignant mesothelioma

    International Nuclear Information System (INIS)

    Recombinant human tumor necrosis factor (rHuTNF) was evaluated both for direct anti-tumor action against human malignant mesothelioma and for its capacity to augment the generation and lytic phases of lymphocyte-mediated cytotoxicity against this tumor. rHuTNF was directly toxic by MTT assay to one of two mesothelioma cell lines evaluated, but had no effect on susceptibility to subsequent lymphocyte-mediated lysis of either line. TNF alone was incapable of generating anti-mesothelioma lymphokine-activated killer cell (LAK) activity. Furthermore, it did not augment the degree or LAK activity produced by submaximal interleukin-2 (IL-2) concentrations nor did it augment lysis of mesothelioma cells by natural killer (NK) or LAK effector cells during the 4-hr 51chromium release cytolytic reaction. The studies also suggest that mesothelioma targets are less responsive to TNF plus submaximal IL-2 concentrations than the standard LAK sensitive target Daudi, raising the possibility that intermediate LAK sensitive tumors such as mesothelioma may require separate and specific evaluation in immunomodulation studies. This in vitro study indicates that use of low-dose rHuTNF and IL-2 is unlikely to be an effective substitute for high-dose IL-2 in generation and maintenance of LAK activity in adoptive immunotherapy for mesothelioma

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  17. An Essential Role for Tumor Necrosis Factor in Natural Killer Cell–mediated Tumor Rejection in the Peritoneum

    OpenAIRE

    Smyth, Mark J.; Kelly, Janice M.; Baxter, Alan G.; Körner, Heinrich; Sedgwick, Jonathon D.

    1998-01-01

    Natural killer (NK) cells are thought to provide the first line of defence against tumors, particularly major histocompatibility complex (MHC) class I− variants. We have confirmed in C57BL/6 (B6) mice lacking perforin that peritoneal growth of MHC class I− RMA-S tumor cells in unprimed mice is controlled by perforin-dependent cytotoxicity mediated by CD3− NK1.1+ cells. Furthermore, we demonstrate that B6 mice lacking tumor necrosis factor (TNF) are also significantly defective in their reject...

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

    OpenAIRE

    Miki, Yoshimi; Yamamoto, Kei(Department of Physics, Niigata University, Niigata 950-2181, Japan); 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

    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...

  19. 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

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

    Directory of Open Access Journals (Sweden)

    Dinesh Thotala

    Full Text Available 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.

  1. 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.

  2. Integrin Receptors on Tumor Cells Facilitate NK cell-mediated Antibody-dependent Cytotoxicity

    OpenAIRE

    Anikeeva, Nadia; Steblyanko, Maria; Fayngerts, Svetlana; Kopylova, Natalya; Marshall, Deborah J.; Powers, Gordon D.; Sato, Takami; Campbell, Kerry S.; Sykulev, Yuri

    2014-01-01

    NK cells that mediate ADCC play an important role in tumor-specific immunity. We have examined factors limiting specific lysis of tumor cells by CD16.NK-92 cells induced by CNTO 95LF antibodies recognizing αV integrins that are overexpressed on many tumor cells. Although all tested tumor cells were killed by CD16.NK-92 effectors in the presence of the antibodies, the killing of target cells with a low level of ICAM-1 expression revealed a dramatic decrease in their specific lysis at high anti...

  3. A HLA-A2-restricted CTL epitope induces anti-tumor effects against human lung cancer in mouse xenograft model.

    Science.gov (United States)

    Sher, Yuh-Pyng; Lin, Su-I; Chen, I-Hua; Liu, Hsin-Yu; Lin, Chen-Yuan; Chiang, I-Ping; Roffler, Steve; Chen, Hsin-Wei; Liu, Shih-Jen

    2016-01-01

    Cancer immunotherapy is attractive for antigen-specific T cell-mediated anti-tumor therapy, especially in induction of cytotoxic T lymphocytes. In this report, we evaluated human CTL epitope-induced anti-tumor effects in human lung cancer xenograft models. The tumor associated antigen L6 (TAL6) is highly expressed in human lung cancer cell lines and tumor specimens as compared to normal lung tissues. TAL6 derived peptides strongly inhibited tumor growth, cancer metastasis and prolonged survival time in HLA-A2 transgenic mice immunized with a formulation of T-helper (Th) peptide, synthetic CpG ODN, and adjuvant Montanide ISA-51 (ISA-51). Adoptive transfer of peptide-induced CTL cells from HLA-A2 transgenic mice into human tumor xenograft SCID mice significantly inhibited tumor growth. Furthermore, combination of CTL-peptide immunotherapy and gemcitabine additively improved the therapeutic effects. This pre-clinical evaluation model provides a useful platform to develop efficient immunotherapeutic drugs to treat lung cancer and demonstrates a promising strategy with benefit of antitumor immune responses worthy of further development in clinical trials. PMID:26621839

  4. 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.

  5. 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.

  6. 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.

  7. Vaccinia Virus-mediated Therapy of Solid Tumor Xenografts: Intra-tumoral Delivery of Therapeutic Antibodies

    OpenAIRE

    Huang, Ting

    2013-01-01

    Over the past 30 years, much effort and financial support have been invested in the fight against cancer, yet cancer still represents the leading cause of death in the world. Conventional therapies for treatment of cancer are predominantly directed against tumor cells. Recently however, new treatments options have paid more attention to exploiting the advantage of targeting the tumor stroma instead. Vaccinia virus (VACV) has played an important role in human medicine since the 18th century...

  8. 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.

  9. 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.

  10. 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.

  11. Integrin receptors on tumor cells facilitate NK cell-mediated antibody-dependent cytotoxicity.

    Science.gov (United States)

    Anikeeva, Nadia; Steblyanko, Maria; Fayngerts, Svetlana; Kopylova, Natalya; Marshall, Deborah J; Powers, Gordon D; Sato, Takami; Campbell, Kerry S; Sykulev, Yuri

    2014-08-01

    NK cells that mediate ADCC play an important role in tumor-specific immunity. We have examined factors limiting specific lysis of tumor cells by CD16.NK-92 cells induced by CNTO 95LF antibodies recognizing αV integrins that are overexpressed on many tumor cells. Although all tested tumor cells were killed by CD16.NK-92 effectors in the presence of the antibodies, the killing of target cells with a low level of ICAM-1 expression revealed a dramatic decrease in their specific lysis at high antibody concentration, revealing a dose limiting effect. A similar effect was also observed with primary human NK cells. The effect was erased after IFN-γ treatment of tumor cells resulting in upregulation of ICAM-1. Furthermore, killing of the same tumor cells induced by Herceptin antibody was significantly impaired in the presence of CNTO 95Ala-Ala antibody variant that blocks αV integrins but is incapable of binding to CD16. These data suggest that αV integrins on tumor cells could compensate for the loss of ICAM-1 molecules, thereby facilitating ADCC by NK cells. Thus, NK cells could exercise cytolytic activity against ICAM-1 deficient tumor cells in the absence of proinflammatory cytokines, emphasizing the importance of NK cells in tumor-specific immunity at early stages of cancer. PMID:24810893

  12. 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

  13. 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

  14. Magnetic resonance characterization of tumor microvessels in experimental breast tumors using a slow clearance blood pool contrast agent (carboxymethyldextran-A2-Gd-DOTA) with histopathological correlation

    International Nuclear Information System (INIS)

    Carboxymethyldextran (CMD)-A2-Gd-DOTA, a slow clearance blood pool contrast agent with a molecular weight of 52.1 kDa, designed to have intravascular residence for more than 1 h, was evaluated for its potential to characterize and differentiate the microvessels of malignant and benign breast tumors. Precontrast single-slice inversion-recovery snapshot FLASH and dynamic contrast-enhanced MRI using an axial T1-weighted three-dimensional spoiled gradient recalled sequence was performed in 30 Sprague-Dawley rats with chemically induced breast tumors. Endothelial transfer coefficient and fractional plasma volume of the breast tumors were estimated from MRI data acquired with CMD-A2-Gd-DOTA enhancement injected at a dose of 0.1 mmol Gd/kg body weight using a two-compartment bidirectional model of the tumor tissue. The correlation between MRI microvessel characteristics and histopathological tumor grade was determined using the Scarff-Bloom-Richardson method. Using CMD-A2-Gd-DOTA, no significant correlations were found between the MR-estimated endothelial transfer coefficient or plasma volumes with histological tumor grade. Analysis of CMD-A2-Gd-DOTA-enhanced MR kinetic data failed to demonstrate feasibility for the differentiation of benign from malignant tumors or for image-based tumor grading. (orig.)

  15. 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

  16. 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. PMID:27411588

  17. 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...

  18. 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

  19. 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.

  20. Tumor-derived microvesicles mediate human breast cancer invasion through differentially glycosylated EMMPRIN

    Science.gov (United States)

    Menck, Kerstin; Scharf, Christian; Bleckmann, Annalen; Dyck, Lydia; Rost, Ulrike; Wenzel, Dirk; Dhople, Vishnu M.; Siam, Laila; Pukrop, Tobias; Binder, Claudia; Klemm, Florian

    2015-01-01

    Tumor cells secrete not only a variety of soluble factors, but also extracellular vesicles that are known to support the establishment of a favorable tumor niche by influencing the surrounding stroma cells. Here we show that tumor-derived microvesicles (T-MV) also directly influence the tumor cells by enhancing their invasion in a both autologous and heterologous manner. Neither the respective vesicle-free supernatant nor MV from benign mammary cells mediate invasion. Uptake of T-MV is essential for the proinvasive effect. We further identify the highly glycosylated form of the extracellular matrix metalloproteinase inducer (EMMPRIN) as a marker for proinvasive MV. EMMPRIN is also present at high levels on MV from metastatic breast cancer patients in vivo. Anti-EMMPRIN strategies, such as MV deglycosylation, gene knockdown, and specific blocking peptides, inhibit MV-induced invasion. Interestingly, the effect of EMMPRIN-bearing MV is not mediated by matrix metalloproteinases but by activation of the p38/MAPK signaling pathway in the tumor cells. In conclusion, T-MV stimulate cancer cell invasion via a direct feedback mechanism dependent on highly glycosylated EMMPRIN. PMID:25503107

  1. AKT-mediated enhanced aerobic glycolysis causes acquired radioresistance by human tumor cells

    International Nuclear Information System (INIS)

    Background and purpose: Cellular radioresistance is a major impediment to effective radiotherapy. Here, we demonstrated that long-term exposure to fractionated radiation conferred acquired radioresistance to tumor cells due to AKT-mediated enhanced aerobic glycolysis. Material and methods: Two human tumor cell lines with acquired radioresistance were established by long-term exposure to fractionated radiation with 0.5 Gy of X-rays. Glucose uptake was inhibited using 2-deoxy-D-glucose, a non-metabolizable glucose analog. Aerobic glycolysis was assessed by measuring lactate concentrations. Cells were then used for assays of ROS generation, survival, and cell death as assessed by annexin V staining. Results: Enhanced aerobic glycolysis was shown by increased glucose transporter Glut1 expression and a high lactate production rate in acquired radioresistant cells compared with parental cells. Inhibiting the AKT pathway using the AKT inhibitor API-2 abrogated these phenomena. Moreover, we found that inhibiting glycolysis with 2-deoxy-D-glucose suppressed acquired tumor cell radioresistance. Conclusions: Long-term fractionated radiation confers acquired radioresistance to tumor cells by AKT-mediated alterations in their glucose metabolic pathway. Thus, tumor cell metabolic pathway is an attractive target to eliminate radioresistant cells and improve radiotherapy efficacy

  2. Rac1 is required for Prkar1a-mediated Nf2 suppression in Schwann cell tumors

    OpenAIRE

    Manchanda, Parmeet K.; Jones, Georgette N.; Lee, Audrey A.; Pringle, Daphne R.; ZHANG, MEI; Yu, Lianbo; La Perle, Krista M.D.; Kirschner, Lawrence S.

    2012-01-01

    Schwannomas are peripheral nerve sheath tumors that often occur in the setting of an inherited tumor predisposition syndrome, including Neurofibromatosis Types 1 (NF1) and 2 (NF2), Familial Schwannomatosis (FS) and Carney Complex (CNC). Loss of the NF2 tumor suppressor (encoding NF2, or Merlin) is associated with upregulation of the Rac1 small GTPase, which is thought to play a key role in mediating tumor formation. In prior studies, we generated a mouse model of schwannomas by performing tis...

  3. 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.

  4. Hypoxia Mediated Downregulation of miRNA Biogenesis Promotes Tumor Progression

    OpenAIRE

    Rupaimoole, Rajesha; Wu, Sherry Y.; Pradeep, Sunila; Ivan, Cristina; Pecot, Chad V.; Gharpure, Kshipra M.; Nagaraja, Archana S; Armaiz-Pena, Guillermo N.; McGuire, Michael; Zand, Behrouz; Dalton, Heather J.; Filant, Justyna; Miller, Justin Bottsford; Lu, Chunhua; Sadaoui, Nouara C.

    2014-01-01

    Cancer-related deregulation of miRNA biogenesis has been suggested, but the underlying mechanisms remain elusive. Here, we report a previously unrecognized effect of hypoxia in the downregulation of Drosha and Dicer in cancer cells that leads to dysregulation of miRNA biogenesis and increased tumor progression. We show that hypoxia mediated downregulation of Drosha is dependent on ETS1/ELK1 transcription factors. Moreover, mature miRNA array and deep sequencing studies reveal altered miRNA ma...

  5. 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.

  6. Annexin A2 as a differential diagnostic marker of hepatocellular tumors.

    Science.gov (United States)

    Longerich, Thomas; Haller, Maria Theresia; Mogler, Carolin; Aulmann, Sebastian; Lohmann, Volker; Schirmacher, Peter; Brand, Karsten

    2011-01-15

    While improved imaging techniques have made it possible to detect focal liver lesions smaller than 1cm in diameter, differentiating benign lesions from hepatocellular carcinoma (HCC) still remains a challenge. To address this problem and obtain a definite diagnosis, needle core biopsies are often performed, leading to an increased need for supportive ancillary techniques in the histopathological assessment of highly differentiated hepatocellular tumors. Here we evaluate the diagnostic value of immunohistologically detected Annexin A2 (ANXA2) expression in highly differentiated liver tumors. ANXA2 is a calcium-dependent phospholipid-binding protein that has been linked to malignant transformation and HCC development. Our data show that adding sinusoidal ANXA2 expression to the already established marker panel (GPC3, GS, and HSP70) increases the accuracy for the detection of well-differentiated HCC (74% sensitivity, 100% specificity). In addition, in our series, the combinations ANXA2-GPC3 and ANXA2-GS performed better compared to the other established marker combinations. In conclusion, we suggest that adding ANXA2 to the established diagnostic marker panel increases the reliability and objectivity of HCC diagnosis in liver biopsies. PMID:20971570

  7. Agrobacterium-mediated transformation of Cichorium intybus L. with interferon-a2b gene

    OpenAIRE

    Kvasko O. Yu.; Gerasymenko I. M.; Shachovsky A. M.; Matvieieva N. A.; Kuchuk N. V.

    2009-01-01

    An efficient method for the plant regeneration and Agrobacterium mediated transformation with interferon-a2b gene has been developed for chicory C. intybus L. cv. Pala rossa. The regeneration with efficiency about 100 % was induced on the MS medium supplemented with 0.5–2.5 mg/l kinetin and 0.5 mg/l NAA. The transformed plantlets were recovered at a frequency 26,9 % on basal medium with 25 mg/l kanamycin. According to PCR-analysis the nptII and ifn-a2b genes were integrated into the genome of...

  8. Agrobacterium-mediated transformation of Cichorium intybus L. with interferon-a2b gene

    Directory of Open Access Journals (Sweden)

    Kvasko O. Yu.

    2009-04-01

    Full Text Available An efficient method for the plant regeneration and Agrobacterium mediated transformation with interferon-a2b gene has been developed for chicory C. intybus L. cv. Pala rossa. The regeneration with efficiency about 100 % was induced on the MS medium supplemented with 0.5–2.5 mg/l kinetin and 0.5 mg/l NAA. The transformed plantlets were recovered at a frequency 26,9 % on basal medium with 25 mg/l kanamycin. According to PCR-analysis the nptII and ifn-a2b genes were integrated into the genome of transformed plants.

  9. 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

  10. CXCR4 Chemokine Receptor Mediates Prostate Tumor Cell Adhesion through α5 and β3 Integrins

    Directory of Open Access Journals (Sweden)

    Tobias Engl

    2006-04-01

    Full Text Available The mechanisms leading to prostate cancer metastasis are not understood completely. Although there is evidence that the CXC chemokine receptor (CXCR 4 and its ligand CXCL12 may regulate tumor dissemination, their role in prostate cancer is controversial. We examined CXCR4 expression and functionality, and explored CXCL12-triggered adhesion of prostate tumor cells to human endothelium or to extracellular matrix proteins laminin, collagen, and fibronectin. Although little CXCR4 was expressed on LNCaP and DU-145 prostate tumor cells, CXCR4 was still active, enabling the cells to migrate toward a CXCL12 gradient. CXCL12 induced elevated adhesion to the endothelial cell monolayer and to immobilized fibronectin, laminin, and collagen. Anti-CXCR4 antibodies or CXCR4 knock out significantly impaired CXCL 12-triggered tumor cell binding. The effects observed did not depend on CXCR4 surface expression level. Rather, CXCR4-mediated adhesion was established by α5 and β3 integrin subunits and took place in the presence of reduced p38 and p38 phosphorylation. These data show that chemoattractive mechanisms are involved in adhesion processes of prostate cancer cells, and that binding of CXCL12 to its receptor leads to enhanced expression of α5 and β3. The findings provide a link between chemokine receptor expression and integrin-triggered tumor dissemination.

  11. 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

  12. 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

  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. Akt mediated ROS-dependent selective targeting of mutant KRAS tumors.

    Science.gov (United States)

    Iskandar, Kartini; Rezlan, Majidah; Pervaiz, Shazib

    2014-10-01

    Reactive oxygen species (ROS) play a critical role in a variety of cellular processes, ranging from cell survival and proliferation to cell death. Previously, we reported the ability of a small molecule compound, C1, to induce ROS dependent autophagy associated apoptosis in human cancer cell lines and primary tumor cells (Wong C. et al. 2010). Our ongoing investigations have unraveled a hitherto undefined novel signaling network involving hyper-phosphorylation of Akt and Akt-mediated ROS production in cancer cell lines. Interestingly, drug-induced Akt activation is selectively seen in cell lines that carry mutant KRAS; HCT116 cells that carry the V13D KRAS mutation respond favorably to C1 while HT29 cells expressing wild type KRAS are relatively resistant. Of note, not only does the compound target mutant KRAS expressing cells but also induces RAS activation as evidenced by the PAK pull down assay. Corroborating this, pharmacological inhibition as well as siRNA mediated silencing of KRAS or Akt, blocked C1-induced ROS production and rescued tumor colony forming ability in HCT116 cells. To further confirm the involvement of KRAS, we made use of mutant KRAS transformed RWPE-1 prostate epithelial cells. Notably, drug-induced ROS generation and death sensitivity was significantly higher in RWPE-1-KRAS cells than the RWPE-1-vector cells, thus confirming the results obtained with mutant KRAS colorectal carcinoma cell line. Lastly, we made use of HCT116 mutant KRAS knockout cells (KO) where the mutant KRAS allele had been deleted, thus expressing a single wild-type KRAS allele. Exposure of the KO cells to C1 failed to induce Akt activation and mitochondrial ROS production. Taken together, results show the involvement of activated Akt in ROS-mediated selective targeting of mutant KRAS expressing tumors, which could have therapeutic implications given the paucity of chemotherapeutic strategies specifically targeting KRAS mutant cancers. PMID:26461287

  15. Complement bound to tumor target cells enhances their sensitivity to macrophage-mediated killing

    Energy Technology Data Exchange (ETDEWEB)

    Bara, S.; Lint, T.F.

    1986-03-05

    Tumor cells are known to be susceptible to destruction by a variety of immune effector mechanisms including complement (C) and activated macrophages (M theta). The authors have chosen to study the interaction of these two effector systems by examining the effects of bound mouse C on the antibody-independent M theta-mediated lysis of the P815 mouse mastocytoma cell line. Hemolytically active normal mouse serum (NMS) was used to deposit C on tumor targets by an alternative pathway mechanism in the absence of added antibody. C3 was quantitated on the P815 cells by a cellular enzyme-linked immunosorbant assay. C. parvum-activated macrophages produced tumor cytolysis which was measured in a serum-free 16 hour /sup 51/Cr-release assay. Target cells which had been incubated with NMS for 30 min at 37/sup 0/C demonstrated a 30% increase in specific /sup 51/Cr-release at a 1:1 effector to target (E:T) ratio, as compared to targets incubated with heat-inactivated (56/sup 0/C, 30 min) NMS. The treatment of target cells with NMS alone did not cause lysis. At higher E:T ratios specific /sup 51/Cr-release approached a maximum level which was not increased further by C treatment of the target cells. However, at low E:T ratios, NMS increased the specific /sup 51/Cr-release in a dose-dependent fashion; this increase was abrogated by 10 mM EDTA. The kinetics of lysis of C-treated P815 cells by activated M theta does not differ from that of control P815 cells. These results indicate that target-bound C may enhance M theta-mediated killing of tumor cells.

  16. Nonlinear stability of a heterogeneous state in a PDE-ODE model for acid-mediated tumor invasion.

    Science.gov (United States)

    Tao, Youshan; Tello, J Ignacio

    2016-02-01

    This work studies a general reaction-diffusion model for acid-mediated tumor invasion, where tumor cells produce excess acid that primarily kills healthy cells, and thereby invade the microenvironment. The acid diffuses and could be cleared by vasculature, and the healthy and tumor cells are viewed as two species following logistic growth with mutual competition. A key feature of this model is the density-limited diffusion for tumor cells, reflecting that a healthy tissue will spatially constrain a tumor unless shrunk. Under appropriate assumptions on model parameters and on initial data, it is shown that the unique heterogeneous state is nonlinearly stable, which implies a long-term coexistence of the healthy and tumor cells in certain parameter space. Our theoretical result suggests that acidity may play a significant role in heterogeneous tumor progression. PMID:26776259

  17. 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...

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

    OpenAIRE

    Ravshan Burikhanov; Tripti Shrestha-Bhattarai; Nikhil Hebbar; Shirley Qiu; Yanming Zhao; Gerard P. Zambetti; Vivek M. Rangnekar

    2014-01-01

    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...

  19. Macrophage-Mediated Trogocytosis Leads to Death of Antibody-Opsonized Tumor Cells.

    Science.gov (United States)

    Velmurugan, Ramraj; Challa, Dilip K; Ram, Sripad; Ober, Raimund J; Ward, E Sally

    2016-08-01

    Understanding the complex behavior of effector cells such as monocytes or macrophages in regulating cancerous growth is of central importance for cancer immunotherapy. Earlier studies using CD20-specific antibodies have demonstrated that the Fcγ receptor (FcγR)-mediated transfer of the targeted receptors from tumor cells to these effector cells through trogocytosis can enable escape from antibody therapy, leading to the viewpoint that this process is protumorigenic. In the current study, we demonstrate that persistent trogocytic attack results in the killing of HER2-overexpressing breast cancer cells. Further, antibody engineering to increase FcγR interactions enhances this tumoricidal activity. These studies extend the complex repertoire of activities of macrophages to trogocytic-mediated cell death of HER2-overexpressing target cells and have implications for the development of effective antibody-based therapies. Mol Cancer Ther; 15(8); 1879-89. ©2016 AACR. PMID:27226489

  20. 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.

  1. 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.

  2. 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

  3. 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.

  4. 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.

  5. 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. PMID:27348585

  6. 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.

  7. 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

  8. 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

  9. Potentiation of the Anti-Tumor Effect of Merocyanine 540-Mediated Photodynamic Therapy by Amifostine and Amphotericin B

    OpenAIRE

    Tsujino, Ichiro; Miyagi, Kiyoko; Sampson, Reynée W.; Sieber, Fritz

    2006-01-01

    Leukemia and lymphoma cells are much more sensitive to Merocyanine 540 (MC540)-mediated photodynamic therapy (PDT) than normal pluripotent hematopoietic stem cells and normal granulocyte/macrophage progenitors (CFU-GM). By contrast, most solid tumor cells are only moderately sensitive to MC540-PDT. The limited activity against solid tumor cells has detracted from MC540's appeal as a broad-spectrum purging agent. We report here that non-cytotoxic concentrations of amifostine (Ethyol, Ethiofos,...

  10. 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.

  11. Riluzole mediates anti-tumor properties in breast cancer cells independent of metabotropic glutamate receptor-1.

    Science.gov (United States)

    Speyer, Cecilia L; Nassar, Mahdy A; Hachem, Ali H; Bukhsh, Miriam A; Jafry, Waris S; Khansa, Rafa M; Gorski, David H

    2016-06-01

    Riluzole, the only drug approved by the FDA for treating amyotrophic lateral sclerosis, inhibits melanoma proliferation through its inhibitory effect on glutamatergic signaling. We demonstrated that riluzole also inhibits the growth of triple-negative breast cancer (TNBC) and described a role for metabotropic glutamate receptor-1 (GRM1) in regulating TNBC cell growth and progression. However, the role of GRM1 in mediating riluzole's effects in breast cancer has not been fully elucidated. In this study, we seek to determine how much of riluzole's action in breast cancer is mediated through GRM1. We investigated anti-tumor properties of riluzole in TNBC and ER+ cells using cell growth, invasion, and soft-agar assays and compared riluzole activity with GRM1 levels. Using Lentiviral vectors expressing GRM1 or shGRM1, these studies were repeated in cells expressing high or low GRM1 levels where the gene was either silenced or overexpressed. Riluzole inhibited proliferation, invasion, and colony formation in both TNBC and ER+ cells. There was a trend between GRM1 expression in TNBC cells and their response to riluzole in both cell proliferation and invasion assays. However, silencing and overexpression studies had no effect on cell sensitivity to riluzole. Our results clearly suggest a GRM1-independent mechanism through which riluzole mediates its effects on breast cancer cells. Understanding the mechanism by which riluzole mediates breast cancer progression will be useful in identifying new therapeutic targets for treating TNBC and in facilitating stratification of patients in clinical trials using riluzole in conjunction with conventional therapy. PMID:27146584

  12. Overcoming hypoxia-mediated tumor progression: Combinatorial approaches targeting pH regulation, angiogenesis and immune dysfunction

    Directory of Open Access Journals (Sweden)

    Paul C. Mcdonald

    2016-03-01

    Full Text Available Hypoxia is an important contributor to the heterogeneity of the microenvironment of solid tumors and is a significant environmental stressor that drives adaptations which are essential for the survival and metastatic capabilities of tumor cells. Critical adaptive mechanisms include altered metabolism, pH regulation, epithelial-mesenchymal transition, angiogenesis, migration/invasion, diminished response to immune cells and resistance to chemotherapy and radiation therapy. In particular, pH regulation by hypoxic tumor cells, through the modulation of cell surface molecules such as extracellular carbonic anhydrases (CAIX and CAXII and monocarboxylate transporters (MCT-1 and MCT-4 functions to increase cancer cell survival and enhance cell invasion while also contributing to immune evasion. Indeed, CAIX is a vital regulator of hypoxia mediated tumor progression, and targeted inhibition of its function results in reduced tumor growth, metastasis, and cancer stem cell function. However, the integrated contributions of the repertoire of hypoxia-induced effectors of pH regulation for tumor survival and invasion remain to be fully explored and exploited as therapeutic avenues. For example, the clinical use of anti-angiogenic agents has identified a conundrum whereby this treatment increases hypoxia and cancer stem cell components of tumors, and accelerates metastasis. Furthermore, hypoxia results in the infiltration of myeloid-derived suppressor cells (MDSCs, regulatory T cells (Treg and Tumor Associated Macrophages (TAMs, and also stimulates the expression of PD-L1 on tumor cells, which collectively suppress T-cell mediated tumor cell killing. Therefore, combinatorial targeting of angiogenesis, the immune system and pH regulation in the context of hypoxia may lead to more effective strategies for curbing tumor progression and therapeutic resistance, thereby increasing therapeutic efficacy and leading to more effective strategies for the treatment of

  13. A novel extracellular Hsp90 mediated co-receptor function for LRP1 regulates EphA2 dependent glioblastoma cell invasion.

    Directory of Open Access Journals (Sweden)

    Udhayakumar Gopal

    Full Text Available BACKGROUND: Extracellular Hsp90 protein (eHsp90 potentiates cancer cell motility and invasion through a poorly understood mechanism involving ligand mediated function with its cognate receptor LRP1. Glioblastoma multiforme (GBM represents one of the most aggressive and lethal brain cancers. The receptor tyrosine kinase EphA2 is overexpressed in the majority of GBM specimens and is a critical mediator of GBM invasiveness through its AKT dependent activation of EphA2 at S897 (P-EphA2(S897. We explored whether eHsp90 may confer invasive properties to GBM via regulation of EphA2 mediated signaling. PRINCIPAL FINDINGS: We find that eHsp90 signaling is essential for sustaining AKT activation, P-EphA2(S897, lamellipodia formation, and concomitant GBM cell motility and invasion. Furthermore, eHsp90 promotes the recruitment of LRP1 to EphA2 in an AKT dependent manner. A finding supported by biochemical methodology and the dual expression of LRP1 and P-EphA2(S897 in primary and recurrent GBM tumor specimens. Moreover, hypoxia mediated facilitation of GBM motility and invasion is dependent upon eHsp90-LRP1 signaling. Hypoxia dramatically elevated surface expression of both eHsp90 and LRP1, concomitant with eHsp90 dependent activation of src, AKT, and EphA2. SIGNIFICANCE: We herein demonstrate a novel crosstalk mechanism involving eHsp90-LRP1 dependent regulation of EphA2 function. We highlight a dual role for eHsp90 in transducing signaling via LRP1, and in facilitating LRP1 co-receptor function for EphA2. Taken together, our results demonstrate activation of the eHsp90-LRP1 signaling axis as an obligate step in the initiation and maintenance of AKT signaling and EphA2 activation, thereby implicating this pathway as an integral component contributing to the aggressive nature of GBM.

  14. 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.

  15. Xanthatin anti-tumor cytotoxicity is mediated via glycogen synthase kinase-3β and β-catenin.

    Science.gov (United States)

    Tao, Li; Sheng, Xiaobo; Zhang, Lei; Li, Weidong; Wei, Zhonghong; Zhu, Pinting; Zhang, Feng; Wang, Aiyun; Woodgett, James R; Lu, Yin

    2016-09-01

    Xanthatin, a xanthanolide sesquiterpene lactone isolated from Xanthium strumarium L. (Asteraceae), has prominent anti-tumor activity. Initial mechanism of action studies suggested xanthatin triggered activation of Wnt/β-catenin. We examined the effects of xanthatin on signaling pathways in A459 lung cancer cells and mouse embryonic fibroblasts to ascertain requirements for xanthatin-induced cell death and tumor growth in xenografts. Genetic inactivation of GSK-3β, but not the related isoform GSK-3α, compromised xanthatin cytotoxicity while inactivation of β-catenin enhanced xanthatin-mediated cell death. These data provide insight into how xanthatin and related molecules could be effectively targeted toward certain tumors. PMID:27321043

  16. 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

  17. 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

    Two lipophilic methotrexate analogues have been synthesized and evaluated for cytotoxicity against KATO III and HT-29 human colon cancer cells. Both analogues contained a C-16-alkyl chain attached to the gamma-carboxylic acid and one of the analogues had an additional benzyl group attached to the...... tightly anchored to the liposomal carrier. Also, the developed DSC-assay for Studying the anchoring stability of alkylated drugs will be a useful tool in the development of liposomal drug delivery Systems....... 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...... of alkylated compounds in liposomes, it was demonstrated that the MTX-analogue partitioned into the water phase and thereby became available for cell uptake. It was concluded that liposomes containing alkylated MTX-analogues show promise as a drug delivery system, although the MTX-analogue needs to be more...

  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. 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.

  20. 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.

  1. Modulation of in vivo tumor radiation response via gold nanoshell-mediated vascular-focused hyperthermia: characterizing an integrated antihypoxic and localized vascular disrupting targeting strategy.

    Science.gov (United States)

    Diagaradjane, Parmeswaran; Shetty, Anil; Wang, James C; Elliott, Andrew M; Schwartz, Jon; Shentu, Shujun; Park, Hee C; Deorukhkar, Amit; Stafford, R Jason; Cho, Sang H; Tunnell, James W; Hazle, John D; Krishnan, Sunil

    2008-05-01

    We report noninvasive modulation of in vivo tumor radiation response using gold nanoshells. Mild-temperature hyperthermia generated by near-infrared illumination of gold nanoshell-laden tumors, noninvasively quantified by magnetic resonance temperature imaging, causes an early increase in tumor perfusion that reduces the hypoxic fraction of tumors. A subsequent radiation dose induces vascular disruption with extensive tumor necrosis. Gold nanoshells sequestered in the perivascular space mediate these two tumor vasculature-focused effects to improve radiation response of tumors. This novel integrated antihypoxic and localized vascular disrupting therapy can potentially be combined with other conventional antitumor therapies. PMID:18412402

  2. 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.

  3. TRANSFORMING GROWTH FACTOR-BETA MEDIATED SUPPRESSION OF ANTI-TUMOR T CELLS REQUIRES FOXP1 TRANSCRIPTION FACTOR EXPRESSION

    Science.gov (United States)

    Stephen, Tom L.; Rutkowski, Melanie R.; Allegrezza, Michael J.; Perales-Puchalt, Alfredo; Tesone, Amelia J.; Svoronos, Nikolaos; Nguyen, Jenny M.; Sarmin, Fahmida; Borowsky, Mark E.; Tchou, Julia; Conejo-Garcia, Jose R.

    2014-01-01

    SUMMARY Tumor-reactive T cells become unresponsive in advanced tumors. Here we have characterized a common mechanism of T cell unresponsiveness in cancer driven by the up-regulation of the transcription factor Forkhead box protein P1 (Foxp1), which prevents CD8+ T cells from proliferating and up-regulating Granzyme-B and interferon-γ (IFN-γ) in response to tumor antigens. Accordingly, Foxp1-deficient lymphocytes induced rejection of incurable tumors, and promoted protection against tumor re-challenge. Mechanistically, Foxp1 interacted with the transcription factors Smad2 and Smad3 in pre-activated CD8+ T cells in response to microenvironmental transforming growth factor-β (TGF-β), and was essential for its suppressive activity. Therefore, Smad2 and Smad3-mediated c-Myc repression requires Foxp1 expression in T cells. Furthermore, Foxp1 directly mediated TGF-β-induced c-Jun transcriptional repression, which abrogated T cell activity. Our results unveil a fundamental mechanism of T cell unresponsiveness different from anergy or exhaustion, driven by TGF-β signaling on tumor-associated lymphocytes undergoing Foxp1-dependent transcriptional regulation. PMID:25238097

  4. 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.

  5. 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. PMID:27653477

  6. 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)

  7. 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.

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

    International Nuclear Information System (INIS)

    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.

  9. 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.

  10. 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.

  11. 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.

  12. 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

    A p53 peptide-specific CTL line was generated through stimulation with autologous monocyte-derived dendritic cells (DC) pulsed with wild-type HLA-A2 binding p53 derived peptides. A p53 peptide-specific CD8(+) CTL line was established from a healthy HLA-A2 positive donor. The CTL line...... was characterized with respect to specificity, affinity and killing of cell lines derived from p53 mutated spontaneous tumors. The CTL line demonstrated lysis of p53(139-147) pulsed target cells and cold target inhibition experiments as well as antibody blocking confirmed that the killing was epitope-specific, HLA......-A2 restricted and dependent on CD8-binding. Interestingly, the affinity of the CTL line was only in the micromole per liter range and target cells pulsed with less than 0.01 microM peptide were not recognized. Furthermore, 3 HLA-A2(+) p53 mutated tumor cell lines were efficiently lysed by the CTL...

  13. 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

  14. Separation of effector cells mediating antibody-dependent cellular cytotoxicity (ADC) to erythrocyte targets from those mediating ADC to tumor targets.

    Science.gov (United States)

    Pollack, S B; Nelson, K; Grausz, J D

    1976-04-01

    Murine spleen cells mediate antibody-dependent cellular cytotoxicity (ADC) both to erythrocyte targets in a 51Cr release assay and to syngeneic tumor targets in a microcytotoxicity assay. The effector cells active in the two ADC assays can be separated by passage of the spleen cells through columns of Sephadex G-10 at 37 degrees C. Cells mediating ADC to sarcoma cells did not adhere to the G-10 and were recovered in the column effluent. These nonadherent cells were not cytotoxic to antibody-coated chicken red blood cells. Spleen cells which mediated ADC in a 51Cr release assay to the red cell targets adhered to G-10. Adherent effector cells could subsequently be recovered from the columns by elution with 5 X 10(-4) M EDTA. PMID:815438

  15. 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 exposure the rate of H-labeled arachidonic acid release is 3.3 times higher than that observed at normal osmolality. Cell swelling also causes an increase in the production of C-stearic acid-labeled lysophosphatidylcholine. This indicates that a phospholipase A is activated by cell swelling in the Ehrlich...... cells. Within the same time frame there is no swelling-induced increase in C-labeled stearic acid release nor in the synthesis of phosphatidyl C-butanol in the presence of C-butanol. Furthermore, U7312, an inhibitor of phospholipase C, does not affect the swelling induced release of C...

  16. 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.

  17. 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.

  18. Hypoxia induced HMGB1 and mitochondrial DNA interactions mediate tumor growth in hepatocellular carcinoma through Toll Like Receptor 9

    Science.gov (United States)

    Liu, Yao; Yan, Wei; Tohme, Samer; Chen, Man; Fu, Yu; Tian, Dean; Lotze, Michael; Tang, Daolin; Tsung, Allan

    2015-01-01

    Background and aims The mechanisms of hypoxia-induced tumor growth remain unclear. Hypoxia induces intracellular translocation and release of a variety of damage associated molecular patterns (DAMPs) such as nuclear HMGB1 and mitochondrial DNA (mtDNA). In inflammation, Toll-like receptor (TLR)-9 activation by DNA-containing immune complexes has been shown to be mediated by HMGB1. We thus hypothesize that HMGB1 binds mtDNA in the cytoplasm of hypoxic tumor cells and promotes tumor growth through activating TLR9 signaling pathways. Methods C57BL6 mice were injected with Hepa1-6 cancer cells. TLR9 and HMGB1 were inhibited using shRNA or direct antagonists. Huh7 and Hepa1-6 cancer cells were investigated in vitro to investigate how the interaction of HMGB1 and mtDNA activates TLR9 signaling pathways. Results During hypoxia, HMGB1 translocates from the nucleus to the cytosol and binds to mtDNA released from damaged mitochondria. This complex subsequently activates TLR9 signaling pathways to promote tumor cell proliferation. Loss of HMGB1 or mtDNA leads to a defect in TLR9 signaling pathways in response to hypoxia, resulting in decreased tumor cell proliferation. Also, the addition of HMGB1 and mtDNA leads to the activation of TLR-9 and subsequent tumor cell proliferation. Moreover, TLR9 is overexpressed in both hypoxic tumor cells in vitro and in human hepatocellular cancer (HCC) specimens; and, knockdown of either HMGB1 or TLR9 from HCC cells suppressed tumor growth in vivo after injection in mice. Conclusions Our data reveals a novel mechanism by which the interactions of HMGB1 and mtDNA activate TLR9 signaling during hypoxia to induce tumor growth. PMID:25681553

  19. Rac1 is required for Prkar1a-mediated Nf2 suppression in Schwann cell tumors.

    Science.gov (United States)

    Manchanda, P K; Jones, G N; Lee, A A; Pringle, D R; Zhang, M; Yu, L; La Perle, K M D; Kirschner, L S

    2013-07-25

    Schwannomas are peripheral nerve sheath tumors that often occur in the setting of an inherited tumor predisposition syndrome, including neurofibromatosis types 1 (NF1) and 2 (NF2), familial schwannomatosis and Carney complex. Loss of the NF2 tumor suppressor (encoding NF2, or Merlin) is associated with upregulation of the Rac1 small GTPase, which is thought to have a key role in mediating tumor formation. In prior studies, we generated a mouse model of schwannomas by performing tissue-specific knockout (KO) of the Carney complex gene Prkar1a, which encodes the type 1A regulatory subunit of protein kinase A. These tumors exhibited down-regulation of Nf2 protein and an increase in activated Rac1. To assess the requirement for Rac1 in schwannoma formation, we generated a double KO (DKO) of Prkar1a and Rac1 in Schwann cells and monitored tumor formation. Loss of Rac1 reduced tumor formation by reducing proliferation and enhancing apoptosis. Surprisingly, the reduction of tumor formation was accompanied by re-expression of the Nf2 protein. Furthermore, activated Rac1 was able to downregulate Nf2 in vitro in a Pak-dependent manner. These in vivo data indicate that activation of Rac1 is responsible for suppression of Nf2 protein production; deficiency of Nf2 in Schwann cells leads to loss of cellular growth control and tumor formation. Further, PKA activation through mutation in Prkar1a is sufficient to initiate Rac1 signaling, with subsequent reduction of Nf2 and schwannomagenesis. Although in vitro evidence has shown that loss of Nf2 activates Rac1, our data indicate that signaling between Nf2 and Rac1 occurs in a bidirectional fashion, and these interactions are modulated by PKA. PMID:23045281

  20. Epitope diversification driven by non-tumor epitope-specific Th1 and Th17 mediates potent antitumor reactivity.

    Science.gov (United States)

    Ichikawa, Kosuke; Kagamu, Hiroshi; Koyama, Kenichi; Miyabayashi, Takao; Koshio, Jun; Miura, Satoru; Watanabe, Satoshi; Yoshizawa, Hirohisa; Narita, Ichiei

    2012-09-21

    MHC class I-restricted peptide-based vaccination therapies have been conducted to treat cancer patients, because CD8⁺ CTL can efficiently induce apoptosis of tumor cells in an MHC class I-restricted epitope-specific manner. Interestingly, clinical responders are known to demonstrate reactivity to epitopes other than those used for vaccination; however, the mechanism underlying how antitumor T cells with diverse specificity are induced is unclear. In this study, we demonstrated that dendritic cells (DCs) that engulfed apoptotic tumor cells in the presence of non-tumor MHC class II-restricted epitope peptides, OVA(323-339), efficiently presented tumor-associated antigens upon effector-dominant CD4⁺ T cell balance against regulatory T cells (Treg) for the OVA(323-339) epitope. Th1 and Th17 induced tumor-associated antigens presentation of DC, while Th2 ameliorated tumor-antigen presentation for CD8⁺ T cells. Blocking experiments with anti-IL-23p19 antibody and anti-IL-23 receptor indicated that an autocrine mechanism of IL-23 likely mediated the diverted tumor-associated antigens presentation of DC. Tumor-associated antigens presentation of DC induced by OVA(323-339) epitope-specific CD4⁺ T cells resulted in facilitated antitumor immunity in both priming and effector phase in vivo. Notably, this immunotherapy did not require pretreatment to reduce Treg induced by tumor. This strategy may have clinical implications for designing effective antitumor immunotherapies.

  1. Inhibition of tumor cells multidrug resistance by cucumarioside A2-2, frondoside A and their complexes with cholesterol.

    Science.gov (United States)

    Menchinskaya, Ekaterina S; Aminin, Dmitry L; Avilov, Sergey A; Silchenko, Aleksandra S; Andryjashchenko, Pelageya V; Kalinin, Vladimir I; Stonik, Valentin A

    2013-10-01

    In non-cytotoxic concentrations, frondoside A (1) from the sea cucumber Cucumaria okhotensis and cucumarioside A2-2 (2) from C. japonica, as well as their complexes with cholesterol block the activity of membrane transport P-glycoprotein in cells of the ascite form of mouse Ehrlich carcinoma. They prevent in this way an efflux of fluorescent probe Calcein from the cells. Since the blocking of P-glycoprotein activity results in decrease of multidrug resistance, these glycosides and their complexes with cholesterol may be considered as potential inhibitors of multidrug resistance of tumor cells. PMID:24354179

  2. Chimeric peptide containing both B and T cells epitope of tumor-associated antigen L6 enhances anti-tumor effects in HLA-A2 transgenic mice.

    Science.gov (United States)

    Lin, Su-I; Huang, Ming-Hsi; Chang, Yu-Wen; Chen, I-Hua; Roffler, Steve; Chen, Bing-Mae; Sher, Yuh-Pyng; Liu, Shih-Jen

    2016-07-28

    Synthetic peptides are attractive for cancer immunotherapy because of their safety and flexibility. In this report, we identified a new B cell epitope of tumor-associated antigen L6 (TAL6) that could induce antibody-dependent cellular cytotoxicity (ADCC) in vivo. We incorporated the B cell epitope with a cytotoxic T lymphocyte (CTL) and a helper T (Th) epitope to form a chimeric long peptide. We formulated the chimeric peptide with different adjuvants to immunize HLA-A2 transgenic mice and evaluate their immunogenicity. The chimeric peptide formulated with an emulsion type nanoparticle (PELC) adjuvant and a toll-like receptor 9 agonist (CpG ODN) (PELC/CpG) induced the greatest ADCC and CTL responses. The induced anti-tumor immunity inhibited the growth of TAL6-positive cancer cells. Moreover, we observed that immunization with the chimeric peptide inhibited cancer cell migration in vitro and metastasis in vivo. These data suggest that a chimeric peptide containing both B and T cell epitopes of TAL6 formulated with PELC/CpG adjuvant is feasible for cancer immunotherapy. PMID:27130449

  3. 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

  4. Suppression by Apoptotic Cells Defines Tumor Necrosis Factor-Mediated Induction of Glomerular Mesangial Cell Apoptosis by Activated Macrophages

    OpenAIRE

    Duffield, Jeremy S.; Ware, Carl F.; Ryffel, Bernhardt; Savill, John

    2001-01-01

    Activated macrophages (Mφ) isolated from inflamed glomeruli or generated by interferon-γ and lipopolysaccharide treatment in vitro induce glomerular mesangial cell apoptosis by hitherto incompletely understood mechanisms. In this report we demonstrate that nitric oxide-independent killing of co-cultured mesangial cells by interferon-γ/lipopolysaccharide-activated Mφ is suppressed by binding/ingestion of apoptotic cells and is mediated by tumor necrosis factor (TNF). Thus, soluble TNF receptor...

  5. 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.

  6. 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. PMID:27454297

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

    International Nuclear Information System (INIS)

    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 RasHigh/p53Low-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

  8. 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.

  9. Interrogating the Role of Receptor-Mediated Mechanisms: Biological Fate of Peptide-Functionalized Radiolabeled Gold Nanoparticles in Tumor Mice.

    Science.gov (United States)

    Silva, Francisco; Zambre, Ajit; Campello, Maria Paula Cabral; Gano, Lurdes; Santos, Isabel; Ferraria, Ana Maria; Ferreira, Maria João; Singh, Amolak; Upendran, Anandhi; Paulo, António; Kannan, Raghuraman

    2016-04-20

    To get a better insight on the transport mechanism of peptide-conjugated nanoparticles to tumors, we performed in vivo biological studies of bombesin (BBN) peptide functionalized gold nanoparticles (AuNPs) in human prostate tumor bearing mice. Initially, we sought to compare AuNPs with thiol derivatives of acyclic and macrocyclic chelators of DTPA and DOTA types. The DTPA derivatives were unable to provide a stable coordination of (67)Ga, and therefore, the functionalization with the BBN analogues was pursued for the DOTA-containing AuNPs. The DOTA-coated AuNPs were functionalized with BBN[7-14] using a unidentate cysteine group or a bidentate thioctic group to attach the peptide. AuNPs functionalized with thioctic-BBN displayed the highest in vitro cellular internalization (≈ 25%, 15 min) in gastrin releasing peptide (GRP) receptor expressing cancer cells. However, these results fail to translate to in vivo tumor uptake. Biodistribution studies following intravenous (IV) and intraperitoneal (IP) administration of nanoconjugates in tumor bearing mice indicated that the presence of BBN influences to some degree the biological profile of the nanoconstructs. For IV administration, the receptor-mediated pathway appears to be outweighed by the EPR effect. By contrast, in IP administration, it is reasoned that the GRPr-mediated mechanism plays a role in pancreas uptake. PMID:27003101

  10. 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

    2009-02-01

    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 RARgamma and RXRalpha, 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 RARgamma and RXRalpha. 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 RXRalpha 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 RXRalpha as ligand-dependent inhibitors of KLF4-mediated transformation or tumorigenesis. PMID:19197145

  11. Aspirin delays mesothelioma growth by inhibiting HMGB1-mediated tumor progression.

    Science.gov (United States)

    Yang, H; Pellegrini, L; Napolitano, A; Giorgi, C; Jube, S; Preti, A; Jennings, C J; De Marchis, F; Flores, E G; Larson, D; Pagano, I; Tanji, M; Powers, A; Kanodia, S; Gaudino, G; Pastorino, S; Pass, H I; Pinton, P; Bianchi, M E; Carbone, M

    2015-01-01

    High-mobility group box 1 (HMGB1) is an inflammatory molecule that has a critical role in the initiation and progression of malignant mesothelioma (MM). Aspirin (acetylsalicylic acid, ASA) is the most widely used nonsteroidal anti-inflammatory drug that reduces the incidence, metastatic potential and mortality of many inflammation-induced cancers. We hypothesized that ASA may exert anticancer properties in MM by abrogating the carcinogenic effects of HMGB1. Using HMGB1-secreting and -non-secreting human MM cell lines, we determined whether aspirin inhibited the hallmarks of HMGB1-induced MM cell growth in vitro and in vivo. Our data demonstrated that ASA and its metabolite, salicylic acid (SA), inhibit motility, migration, invasion and anchorage-independent colony formation of MM cells via a novel HMGB1-mediated mechanism. ASA/SA, at serum concentrations comparable to those achieved in humans taking therapeutic doses of aspirin, and BoxA, a specific inhibitor of HMGB1, markedly reduced MM growth in xenograft mice and significantly improved survival of treated animals. The effects of ASA and BoxA were cyclooxygenase-2 independent and were not additive, consistent with both acting via inhibition of HMGB1 activity. Our findings provide a rationale for the well documented, yet poorly understood antitumorigenic activity of aspirin, which we show proceeds via HMGB1 inhibition. Moreover, the use of BoxA appears to allow a more efficient HMGB1 targeting while eluding the known gastrointestinal side effects of ASA. Our findings are directly relevant to MM. Given the emerging importance of HMGB1 and its tumor-promoting functions in many cancer types, and of aspirin in cancer prevention and therapy, our investigation is poised to provide broadly applicable information. PMID:26068794

  12. 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...

  13. Monocytes mediate metastatic breast tumor cell adhesion to endothelium under flow

    OpenAIRE

    Evani, Shankar J.; Prabhu, Rajesh G.; Gnanaruban, V.; Finol, Ender A.; Anand K. Ramasubramanian

    2013-01-01

    Endothelial adhesion is necessary for the hematogenous dissemination of tumor cells. However, the metastatic breast tumor cell MDA-MB-231 does not bind to the endothelium under physiological flow conditions, suggesting alternate mechanisms of adhesion. Since monocytes are highly represented in the tumor microenvironment, and also bind to endothelium during inflammation, we hypothesized that the monocytes assist in the arrest of MDA-MB-231 on the endothelium. Using in vitro models of the dynam...

  14. A flagellin-derived toll-like receptor 5 agonist stimulates cytotoxic lymphocyte-mediated tumor immunity.

    Directory of Open Access Journals (Sweden)

    Nicholas D Leigh

    Full Text Available Toll-like receptor (TLR mediated recognition of pathogen associated molecular patterns allows the immune system to rapidly respond to a pathogenic insult. The "danger context" elicited by TLR agonists allows an initially non-immunogenic antigen to become immunogenic. This ability to alter environment is highly relevant in tumor immunity, since it is inherently difficult for the immune system to recognize host-derived tumors as immunogenic. However, immune cells may have encountered certain TLR ligands associated with tumor development, yet the endogenous stimulation is typically not sufficient to induce spontaneous tumor rejection. Of special interest are TLR5 agonists, because there are no endogenous ligands that bind TLR5. CBLB502 is a pharmacologically optimized TLR5 agonist derived from Salmonella enterica flagellin. We examined the effect of CBLB502 on tumor immunity using two syngeneic lymphoma models, both of which do not express TLR5, and thus do not directly respond to CBLB502. Upon challenge with the T-cell lymphoma RMAS, CBLB502 treatment after tumor inoculation protects C57BL/6 mice from death caused by tumor growth. This protective effect is both natural killer (NK cell- and perforin-dependent. In addition, CBLB502 stimulates clearance of the B-cell lymphoma A20 in BALB/c mice in a CD8(+ T cell-dependent fashion. Analysis on the cellular level via ImageStream flow cytometry reveals that CD11b(+ and CD11c(+ cells, but neither NK nor T cells, directly respond to CBLB502 as determined by NFκB nuclear translocation. Our findings demonstrate that CBLB502 stimulates a robust antitumor response by directly activating TLR5-expressing accessory immune cells, which in turn activate cytotoxic lymphocytes.

  15. NCAM- and FGF-2-mediated FGFR1 signaling in the tumor microenvironment of esophageal cancer regulates the survival and migration of tumor-associated macrophages and cancer cells.

    Science.gov (United States)

    Takase, Nobuhisa; Koma, Yu-Ichiro; Urakawa, Naoki; Nishio, Mari; Arai, Noriaki; Akiyama, Hiroaki; Shigeoka, Manabu; Kakeji, Yoshihiro; Yokozaki, Hiroshi

    2016-09-28

    Tumor-associated macrophages (TAMs) have important roles in the angiogenesis and tumor immunosuppression of various cancers, including esophageal squamous cell carcinomas (ESCCs). To elucidate the roles of TAMs in ESCCs, we compared the gene expression profiles between human peripheral blood monocyte-derived macrophage-like cells (Macrophage_Ls) and Macrophage_Ls stimulated with conditioned medium of the TE series human ESCC cell line (TECM) (TAM_Ls) using cDNA microarray analysis. Among the highly expressed genes in TAM_Ls, we focused on neural cell adhesion molecule (NCAM). NCAM knockdown in TAM_Ls revealed a significant decrease of migration and survival via a suppression of PI3K-Akt and fibroblast growth factor receptor 1 (FGFR1) signaling. Stimulation by TECM up-regulated the level of FGFR1 in Macrophage_Ls. Recombinant human fibroblast growth factor-2 (rhFGF-2) promoted the migration and survival of TAM_Ls and TE-cells through FGFR1 signaling. Our immunohistochemical analysis of 70 surgically resected ESCC samples revealed that the up-regulated FGF-2 in stromal cells, including macrophages, was associated with more aggressive phenotypes and a high number of infiltrating M2 macrophages. These findings may indicate a novel role of NCAM- and FGF-2-mediated FGFR1 signaling in the tumor microenvironment of ESCCs. PMID:27317650

  16. A2A adenosine receptor-mediated increase in coronary flow in hyperlipidemic APOE–knockout mice

    OpenAIRE

    Teng, Bunyen

    2011-01-01

    Bunyen Teng, S Jamal MustafaDepartment of Physiology and Pharmacology and Center for Cardiovascular and Respiratory Sciences, West Virginia University, Morgantown, WV, USAAbstract: Adenosine-induced coronary vasodilation is predominantly A2A adenosine receptor (AR)-mediated, whereas A1 AR is known to negatively modulate the coronary flow (CF). However, the coronary responses to adenosine in hyperlipidemia and atherosclerosis are not well understood. Using hyperlipidemic/atherosclerotic apolip...

  17. 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.

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

    Science.gov (United States)

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

    2009-01-01

    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.

  19. 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.

    2014-01-01

    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. PMID:24957295

  20. 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.

  1. 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.

  2. Early detection of tumor masses by in vivo hematoporphyrin-mediated fluorescence imaging

    Science.gov (United States)

    Autiero, Maddalena; Celentano, Luigi; Cozzolino, Rosanna; Laccetti, Paolo; Marotta, Marcello; Mettivier, Giovanni; Cristina Montesi, Maria; Quarto, Maria; Riccio, Patrizia; Roberti, Giuseppe; Russo, Paolo

    2007-02-01

    We investigated the capability of fluorescence reflectance imaging (FRI) for the early detection of surface tumors in mice. We used a hematoporphyrin (HP) compound (HP dichlorohydrate) as a red fluorescent marker and a low noise, high sensitivity, digital CCD camera for fluorescence imaging. In this preliminary study, highly malignant anaplastic human thyroid carcinoma cells were implanted subcutaneously in one mouse and their growth was monitored daily for 5 days by FRI. The selective HP uptake by the tumor tissues was successfully observed: we observed the fluorescence of tumor only 3 days after cancer cells injection, i.e. when the tumor mass was neither visible (to the naked eye) or palpable. These measurements indicate that FRI is a suitable technique to detect minute subcutaneous tumor masses. This FRI system will be coupled to a radionuclide imaging system based on a CdTe detector for in vivo multimodal imaging in mice.

  3. 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.

  4. Complete destruction of deep-tissue buried tumors via combination of gene silencing and gold nanoechinus-mediated photodynamic therapy.

    Science.gov (United States)

    Vijayaraghavan, Priya; Vankayala, Raviraj; Chiang, Chi-Shiun; Sung, Hsing-Wen; Hwang, Kuo Chu

    2015-09-01

    Cancer is one of the major diseases leading to human deaths. Complete destruction of deep tissue-buried tumors using non-invasive therapies is a grand challenge in clinical cancer treatments. Many therapeutic modalities were developed to tackle this problem, but only partial tumor suppression or delay growths were usually achieved. In this study, we report for the first time that complete destruction of deep tissue-buried tumors can be achieved by combination of gold nanoechinus (Au NEs)-mediated photodynamic therapy (PDT) and gene silencing under ultra-low doses of near infra-red (NIR) light irradiation (915 nm, 340 mW/cm(2); 1064 nm, 420 mW/cm(2)) in the first and second biological windows. The average lifespan of the mice treated by the above combined therapy is beyond 40 days, which are ∼ 2.6 times longer than that (15 days) observed from the anticancer drug doxorubicin-treated group. The current study points out a new direction for the therapeutic design to treat deeply seated tumors in future cancer treatments. PMID:26016691

  5. Human gene transfer: Characterization of human tumor-infiltrating lymphocytes as vehicles for retroviral-mediated gene transfer in man

    International Nuclear Information System (INIS)

    Tumor-infiltrating lymphocytes (TILs) are cells generated from tumor suspensions cultured in interleukin 2 that can mediate cancer regression when adoptively transferred into mice or humans. Since TILs proliferate rapidly in vitro, recirculate, and preferentially localize at the tumor site in vivo, they provide an attractive model for delivery of exogenous genetic material into man. To determine whether efficient gene transfer into TILs is feasible. The authors transduced human TILs with the bacterial gene for neomycin-resistance (NeoR) using the retroviral vector N2. The transduced TIL populations were stable and polyclonal with respect to the intact NeoR gene integration and expressed high levels of neomycin phosphotransferase activity. The NeoR gene insertion did not alter the in vitro growth pattern and interleukin 2 dependence of the transduced TILs. Analyses of T-cell receptor gene rearrangement for β- and γ-chain genes revealed the oligoclonal nature of the TIL populations with no major change in the DNA rearrangement patterns or the levels of mRNA expression of the β and γ chains following transduction and selection of TILs in the neomycin analog G418. Human TILs expressed mRNA for tumor necrosis factors (α and β) and interleukin 2 receptor P55. This pattern of cytokine-mRNA expression was not significantly altered following the transduction of TILs. The studies demonstrate the feasibility of TILs as suitable cellular vehicles for the introduction of therapeutic genes into patients receiving autologous TILs

  6. 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.

  7. X-linked inhibitor of apoptosis protein mediates tumor cell resistance to antibody-dependent cellular cytotoxicity.

    Science.gov (United States)

    Evans, M K; Sauer, S J; Nath, S; Robinson, T J; Morse, M A; Devi, G R

    2016-01-01

    Inflammatory breast cancer (IBC) is the deadliest, distinct subtype of breast cancer. High expression of epidermal growth factor receptors [EGFR or human epidermal growth factor receptor 2 (HER2)] in IBC tumors has prompted trials of anti-EGFR/HER2 monoclonal antibodies to inhibit oncogenic signaling; however, de novo and acquired therapeutic resistance is common. Another critical function of these antibodies is to mediate antibody-dependent cellular cytotoxicity (ADCC), which enables immune effector cells to engage tumors and deliver granzymes, activating executioner caspases. We hypothesized that high expression of anti-apoptotic molecules in tumors would render them resistant to ADCC. Herein, we demonstrate that the most potent caspase inhibitor, X-linked inhibitor of apoptosis protein (XIAP), overexpressed in IBC, drives resistance to ADCC mediated by cetuximab (anti-EGFR) and trastuzumab (anti-HER2). Overexpression of XIAP in parental IBC cell lines enhances resistance to ADCC; conversely, targeted downregulation of XIAP in ADCC-resistant IBC cells renders them sensitive. As hypothesized, this ADCC resistance is in part a result of the ability of XIAP to inhibit caspase activity; however, we also unexpectedly found that resistance was dependent on XIAP-mediated, caspase-independent suppression of reactive oxygen species (ROS) accumulation, which otherwise occurs during ADCC. Transcriptome analysis supported these observations by revealing modulation of genes involved in immunosuppression and oxidative stress response in XIAP-overexpressing, ADCC-resistant cells. We conclude that XIAP is a critical modulator of ADCC responsiveness, operating through both caspase-dependent and -independent mechanisms. These results suggest that strategies targeting the effects of XIAP on caspase activation and ROS suppression have the potential to enhance the activity of monoclonal antibody-based immunotherapy. PMID:26821068

  8. ICOS Promotes the Function of CD4+ Effector T Cells during Anti-OX40-Mediated Tumor Rejection.

    Science.gov (United States)

    Metzger, Todd C; Long, Hua; Potluri, Shobha; Pertel, Thomas; Bailey-Bucktrout, Samantha L; Lin, John C; Fu, Tihui; Sharma, Padmanee; Allison, James P; Feldman, Reid M R

    2016-07-01

    ICOS is a T-cell coregulatory receptor that provides a costimulatory signal to T cells during antigen-mediated activation. Antitumor immunity can be improved by ICOS-targeting therapies, but their mechanism of action remains unclear. Here, we define the role of ICOS signaling in antitumor immunity using a blocking, nondepleting antibody against ICOS ligand (ICOS-L). ICOS signaling provided critical support for the effector function of CD4(+) Foxp3(-) T cells during anti-OX40-driven tumor immune responses. By itself, ICOS-L blockade reduced accumulation of intratumoral T regulatory cells (Treg), but it was insufficient to substantially inhibit tumor growth. Furthermore, it did not impede antitumor responses mediated by anti-4-1BB-driven CD8(+) T cells. We found that anti-OX40 efficacy, which is based on Treg depletion and to a large degree on CD4(+) effector T cell (Teff) responses, was impaired with ICOS-L blockade. In contrast, the provision of additional ICOS signaling through direct ICOS-L expression by tumor cells enhanced tumor rejection and survival when administered along with anti-OX40 therapy. Taken together, our results showed that ICOS signaling during antitumor responses acts on both Teff and Treg cells, which have opposing roles in promoting immune activation. Thus, effective therapies targeting the ICOS pathway should seek to promote ICOS signaling specifically in effector CD4(+) T cells by combining ICOS agonism and Treg depletion. Cancer Res; 76(13); 3684-9. ©2016 AACR. PMID:27197182

  9. A biomimetic nanovector-mediated targeted cholesterol-conjugated siRNA delivery for tumor gene therapy.

    Science.gov (United States)

    Ding, Yang; Wang, Wei; Feng, Meiqing; Wang, Yu; Zhou, Jianping; Ding, Xuefang; Zhou, Xin; Liu, Congyan; Wang, Ruoning; Zhang, Qiang

    2012-12-01

    RNA interference holds tremendous potential as a therapeutic approach of malignant tumors. However, safe and efficient nanovectors are extremely lack for systemic delivery of small interfering RNA (siRNA). The study aimed to develop a biomimetic nanovector, reconstituted high density lipoprotein (rHDL), mediating targeted cholesterol-conjugated siRNA (Chol-siRNA) delivery for Pokemon gene silencing therapy. Chol-siRNA-loaded rHDL nanoparticles (rHDL/Chol-siRNA complexes) were prepared using thin-film dispersion method and their characteristics were investigated in detail. RHDL/Chol-siRNA complexes at the optimal volume ratio (lipid: Chol-siRNA) exhibited high Chol-siRNA-loading efficiency (~99%), desirable nanoparticle size and excellent stability in serum. In addition, by analyzing Chol-siRNA release profile, rHDL/Chol-siRNA complexes displayed sustained-release characteristic and storage stability. Observations from FACS and confocal microscopic analyses revealed that rHDL-mediated carboxyfluorescein tagged Chol-siRNA (FAM-Chol-siRNA) transfection resulted in highly efficient uptake and specific cytoplasmic delivery of FAM-Chol-siRNA into human hepatocellular carcinoma cell line HepG2 via HDL-receptor mediated mechanism. In vitro cytotoxicity, apoptosis and Western-blot analyses revealed significant cellular growth inhibition and decrease of Pokemon and Bcl-2 protein expression in HepG2 cells treated with Chol-siRNA-Pokemon-loaded rHDL nanoparticles (rHDL/Chol-siRNA-Pokemon complexes), respectively. In in vivo studies, the near-infrared (NIR) dye Cy5 labeled Chol-siRNA-loaded rHDL nanoparticles (rHDL/Cy5-Chol-siRNA complexes) obviously accumulated in tumor of nude mice after i.v. administration as compared with Cy5-Chol-siRNA-loaded lipoplexes (Lipos/Cy5-Chol-siRNA complexes). Morover, rHDL/Chol-siRNA-Pokemon complexes demonstrated great tumor growth inhibition and significant decrease of Pokemon and Bcl-2 protein expression in vivo. These results suggested that

  10. 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

  11. 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.

  12. 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.

  13. 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

  14. The Potential of Intralesional Rose Bengal to Stimulate T-Cell Mediated Anti-Tumor Responses

    OpenAIRE

    Maker, Ajay V; Prabhakar, Bellur; Pardiwala, Krunal

    2015-01-01

    Rose Bengal (RB) is a red synthetic dye that was initially used in the garment industry and has been used safely for decades as a corneal stain by ophthalmologists. Antineoplastic properties of RB have also been observed, though the mechanism of action remained to be elucidated. Recently, interest in RB as a therapeutic cancer treatment has increased due to significant anti-tumor responses with direct tumor injection in human clinical trials for metastatic melanoma. In these patients, there h...

  15. Sinks, suppressors and antigen presenters: how lymphodepletion enhances T cell-mediated tumor immunotherapy

    OpenAIRE

    Klebanoff, Christopher A.; Khong, Hung T.; Antony, Paul A.; Douglas C Palmer; Restifo, Nicholas P

    2005-01-01

    Lymphodepletion followed by adoptive cell transfer (ACT) of autologous, tumor-reactive T cells boosts antitumor immunotherapeutic activity in mouse and in humans. In the most recent clinical trials, lymphodepletion together with ACT has an objective response rate of 50% in patients with solid metastatic tumors. The mechanisms underlying this recent advance in cancer immunotherapy are beginning to be elucidated and include: the elimination of cellular cytokine ‘sinks’ for homeostatic γC-cytoki...

  16. 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

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

    International Nuclear Information System (INIS)

    Highlights: ► New approach using the probiotic Bifidobacterium bifidum as a vehicle to deliver QDs into the deep tissue of solid tumors in vivo was achieved. ► Bifidobacterium bifidum delivery system has intrinsic biocompatibility. ► 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. 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.

  19. Proposal of a 2-tier histologic grading system for canine cutaneous mast cell tumors to more accurately predict biological behavior.

    Science.gov (United States)

    Kiupel, M; Webster, J D; Bailey, K L; Best, S; DeLay, J; Detrisac, C J; Fitzgerald, S D; Gamble, D; Ginn, P E; Goldschmidt, M H; Hendrick, M J; Howerth, E W; Janovitz, E B; Langohr, I; Lenz, S D; Lipscomb, T P; Miller, M A; Misdorp, W; Moroff, S; Mullaney, T P; Neyens, I; O'Toole, D; Ramos-Vara, J; Scase, T J; Schulman, F Y; Sledge, D; Smedley, R C; Smith, K; W Snyder, P; Southorn, E; Stedman, N L; Steficek, B A; Stromberg, P C; Valli, V E; Weisbrode, S E; Yager, J; Heller, J; Miller, R

    2011-01-01

    Currently, prognostic and therapeutic determinations for canine cutaneous mast cell tumors (MCTs) are primarily based on histologic grade. However, the use of different grading systems by veterinary pathologists and institutional modifications make the prognostic value of histologic grading highly questionable. To evaluate the consistency of microscopic grading among veterinary pathologists and the prognostic significance of the Patnaik grading system, 95 cutaneous MCTs from 95 dogs were graded in a blinded study by 28 veterinary pathologists from 16 institutions. Concordance among veterinary pathologists was 75% for the diagnosis of grade 3 MCTs and less than 64% for the diagnosis of grade 1 and 2 MCTs. To improve concordance among pathologists and to provide better prognostic significance, a 2-tier histologic grading system was devised. The diagnosis of high-grade MCTs is based on the presence of any one of the following criteria: at least 7 mitotic figures in 10 high-power fields (hpf); at least 3 multinucleated (3 or more nuclei) cells in 10 hpf; at least 3 bizarre nuclei in 10 hpf; karyomegaly (ie, nuclear diameters of at least 10% of neoplastic cells vary by at least two-fold). Fields with the highest mitotic activity or with the highest degree of anisokaryosis were selected to assess the different parameters. According to the novel grading system, high-grade MCTs were significantly associated with shorter time to metastasis or new tumor development, and with shorter survival time. The median survival time was less than 4 months for high-grade MCTs but more than 2 years for low-grade MCTs.

  20. Novel action of FOXL2 as mediator of Col1a2 gene autoregulation.

    Science.gov (United States)

    Marongiu, Mara; Deiana, Manila; Marcia, Loredana; Sbardellati, Andrea; Asunis, Isadora; Meloni, Alessandra; Angius, Andrea; Cusano, Roberto; Loi, Angela; Crobu, Francesca; Fotia, Giorgio; Cucca, Francesco; Schlessinger, David; Crisponi, Laura

    2016-08-01

    FOXL2 belongs to the evolutionarily conserved forkhead box (FOX) superfamily and is a master transcription factor in a spectrum of developmental pathways, including ovarian and eyelid development and bone, cartilage and uterine maturation. To analyse its action, we searched for proteins that interact with FOXL2. We found that FOXL2 interacts with specific C-terminal propeptides of several fibrillary collagens. Because these propeptides can participate in feedback regulation of collagen biosynthesis, we inferred that FOXL2 could thereby affect the transcription of the cognate collagen genes. Focusing on COL1A2, we found that FOXL2 indeed affects collagen synthesis, by binding to a DNA response element located about 65Kb upstream of this gene. According to our hypothesis we found that in Foxl2(-/-) mouse ovaries, Col1a2 was elevated from birth to adulthood. The extracellular matrix (ECM) compartmentalizes the ovary during folliculogenesis, (with type I, type III and type IV collagens as primary components), and ECM composition changes during the reproductive lifespan. In Foxl2(-/-) mouse ovaries, in addition to up-regulation of Col1a2, Col3a1, Col4a1 and fibronectin were also upregulated, while laminin expression was reduced. Thus, by regulating levels of extracellular matrix components, FOXL2 may contribute to both ovarian histogenesis and the fibrosis attendant on depletion of the follicle reserve during reproductive aging and menopause. PMID:27212026

  1. Hypoxic tumor kinase signaling mediated by STAT5A in development of castration-resistant prostate cancer.

    Directory of Open Access Journals (Sweden)

    Kathrine Røe

    Full Text Available In this study, we hypothesized that androgen-deprivation therapy (ADT in prostate cancer, although initially efficient, induces changes in the tumor kinome, which subsequently promote development of castration-resistant (CR disease. Recognizing the correlation between tumor hypoxia and poor prognosis in prostate cancer, we further hypothesized that such changes might be influenced by hypoxia. Microarrays with 144 kinase peptide substrates were applied to analyze CWR22 prostate carcinoma xenograft samples from ADT-naïve, androgen-deprived (AD, long-term AD (ADL, and CR disease stages. The impact of hypoxia was assessed by matching the xenograft kinase activity profiles with those acquired from hypoxic and normoxic prostate carcinoma cell cultures, whereas the clinical relevance was evaluated by analyzing prostatectomy tumor samples from patients with locally advanced disease, either in ADT-naïve or early CR disease stages. By using this novel peptide substrate microarray method we revealed high kinase activity mediated by signal transducer and activator of transcription 5A (STAT5A in CR prostate cancer. Additionally, we uncovered high STAT5A kinase activity already in regressing ADL xenografts, before renewed CR growth was evidenced. Finally, since increased STAT5A kinase activity also was detected after exposing prostate carcinoma cells to hypoxia, we propose long-term ADT to induce tumor hypoxia and stimulate STAT5A kinase activity, subsequently leading to renewed CR tumor growth. Hence, the study detected STAT5A as a candidate to be further investigated for its potential as marker of advanced prostate cancer and as possible therapeutic target protein.

  2. 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 ...

  3. 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.

  4. Secretory phospholipase A2-mediated progression of hepatotoxicity initiated by acetaminophen is exacerbated in the absence of hepatic COX-2

    International Nuclear Information System (INIS)

    We have previously reported that among the other death proteins, hepatic secretory phospholipase A2 (sPLA2) is a leading mediator of progression of liver injury initiated by CCl4 in rats. The aim of our present study was to test the hypothesis that increased hepatic sPLA2 released after acetaminophen (APAP) challenge mediates progression of liver injury in wild type (WT) and COX-2 knockout (KO) mice. COX-2 WT and KO mice were administered a normally non lethal dose (400 mg/kg) of acetaminophen. The COX-2 KO mice suffered 60% mortality compared to 100% survival of the WT mice, suggesting higher susceptibility of COX-2 KO mice to sPLA2-mediated progression of acetaminophen hepatotoxicity. Liver injury was significantly higher at later time points in the KO mice compared to the WT mice indicating that the abatement of progression of injury requires the presence of COX-2. This difference in hepatotoxicity was not due to increased bioactivation of acetaminophen as indicated by unchanged cyp2E1 protein and covalently bound 14C-APAP in the livers of KO mice. Hepatic sPLA2 activity and plasma TNF-α were significantly higher after APAP administration in the KO mice. This was accompanied by a corresponding fall in hepatic PGE2 and lower compensatory liver regeneration and repair (3H-thymidine incorporation) in the KO mice. These results suggest that hindered compensatory tissue repair and poor resolution of inflammation for want of beneficial prostaglandins render the liver very vulnerable to sPLA2-mediated progression of liver injury. These findings are consistent with the destructive role of sPLA2 in the progression and expansion of tissue injury as a result of continued hydrolytic breakdown of plasma membrane phospholipids of perinecrotic hepatocytes unless mitigated by sufficient co-induction of COX-2.

  5. 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.

  6. Characteristics of magnetic labeling on liver tumors with anti-alpha-fetoprotein-mediated Fe3O4 magnetic nanoparticles.

    Science.gov (United States)

    Huang, Kai-Wen; Chieh, Jen-Jie; Horng, Herng-Er; Hong, Chin-Yih; Yang, Hong-Chang

    2012-01-01

    For preoperative and intraoperative detection of tumor distribution, numerous multimodal contrast agents, such as magnetic nanoparticles (MNPs) with several examination indicators, are currently in development. However, complex materials, configuration, and cost are required for multimodal contrast agents, accompanied by a high possibility of toxicity and low popularity in clinics. Nevertheless, the magnetic labeling of MNPs using bioprobes should be feasible not only in preoperative magnetic resonance imaging (MRI), but also in intraoperative examination based on other magnetic properties. In this study, anti-alpha-fetoprotein (AFP)-mediated Fe(3)O(4) MNPs, injected into mice with liver tumors, were used to examine the characteristics of magnetic labeling. Using MRI and scanning superconducting-quantum-interference-device biosusceptometry (SSB), based on alternating current (AC) susceptibility, the magnetic labeling occurred significantly on the first day post-injection of anti-AFP magnetic fluid (MF), and then decreased over time. However, for both MF without antibodies and an anti-carcinoembryonic antigen MF, no magnetic labeling occured on the first day of their respective post-injection. The favorable agreement indicates that magnetic labeling possesses two magnetic characteristics: distortion of the imaging field and AC susceptibility. In addition, the results of the biopsy tests, anti-AFP staining, and Prussian blue staining show the same dynamics as those of magnetic methodologies and prove that bound MNPs on tumor tissue are rotatable by an AC magnetic field to express AC susceptibility. Therefore, with the simple configuration of antibody-mediated MNPs, magnetic labeling is also feasible for intraoperative examinations using SSB with high mobility and sensitivity. PMID:22787394

  7. 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.

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

    International Nuclear Information System (INIS)

    Purpose: 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. Materials and methods: 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 deg. C was reached at one sensor. Ventilation and perfusion were discontinued for 6 min each to assess their effects on temperature development. Results: 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 deg. C (mean value, P < 0.05); without ventilation it increased about 7.0 deg. C (mean value, P < 0.05). Conclusion: Ventilation- and perfusion-mediated tissue cooling 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Vietze, Andrea, E-mail: anvie@gmx.de [Department of Diagnostic Radiology and Neuroradiology, Ernst-Moritz-Arndt-Universitaet Greifswald, Sauerbruchstrasse, 17487 Greifswald (Germany); Koch, Franziska, E-mail: franzi_koch@hotmail.com [Department of Diagnostic Radiology and Neuroradiology, Ernst-Moritz-Arndt-Universitaet Greifswald, Sauerbruchstrasse, 17487 Greifswald (Germany); Laskowski, Ulrich, E-mail: ulrich.laskowski@klinikum-luedenscheid.de [Department of Vascular and Thoracic Surgery, Klinikum Luedenscheid, Paulmannshoeher Strasse 14, 58515 Luedenscheid (Germany); Linder, Albert, E-mail: albert.linder@klinikum-bremen-ost.de [Department of Thoracic Surgery, Klinikum Bremen-Ost, Zuericher Strasse 40, 28325 Bremen (Germany); Hosten, Norbert, E-mail: hosten@uni-greifswald.de [Department of Diagnostic Radiology and Neuroradiology, Ernst-Moritz-Arndt-Universitaet Greifswald, Sauerbruchstrasse, 17487 Greifswald (Germany)

    2011-11-15

    Purpose: 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. Materials and methods: 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 deg. C was reached at one sensor. Ventilation and perfusion were discontinued for 6 min each to assess their effects on temperature development. Results: 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 deg. C (mean value, P < 0.05); without ventilation it increased about 7.0 deg. C (mean value, P < 0.05). Conclusion: Ventilation- and perfusion-mediated tissue cooling 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.

  10. Regression of established pulmonary metastases and subcutaneous tumor mediated by the systemic administration of high-dose recombinant interleukin 2

    International Nuclear Information System (INIS)

    Incubation of resting lymphoid cells with recombinant interleukin 2 (IL-2) in vitro leads to the generation of lymphokine activated killer (LAK) cells capable of lysing fresh tumor cell suspensions in short-term chromium-release assays. Previous studies have demonstrated that the injection of LAK cells plus low doses of recombinant IL-2 were capable of inhibiting the growth of pulmonary metastases. The authors have now explored the ability of high doses of recombinant IL-2, administered systemically, to generate LAK cells in vivo, and to mediate antitumor effects directly. Doses of 100,000 U recombinant IL-2 administered intraperitoneally approximately every 8 h for 5 d were capable of dramatically inhibiting established 3-d pulmonary metastases from the MCA-105 and MCA-106 syngeneic sarcomas and the syngeneic B16 melanoma in C57BL/6 mice. Grossly visible metastases present at 10 d after tumor injection also underwent regression following IL-2 therapy. All antitumor effects of the systemic administration of recombinant IL-2 were eliminated if mice received prior treatment with 500 rad total body irradiation. The administration of high doses of recombinant IL-2 was also capable of inhibiting the growth of 3-d established subcutaneous tumors from the MCA-105 sarcoma, and of mediating the inhibition of growth and regression of established palpable subcutaneous MCA-105 sarcomas. The ready availability of high doses of recombinant human IL-2, and the demonstration of antitumor effects seen in animal models have led us to the initiation of the clinical trials of recombinant IL-2 in humans

  11. 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.

  12. Exosome-mediated transfer from the tumor microenvironment increases TGFβ signaling in squamous cell carcinoma.

    Science.gov (United States)

    Languino, Lucia R; Singh, Amrita; Prisco, Marco; Inman, Gareth J; Luginbuhl, Adam; Curry, Joseph M; South, Andrew P

    2016-01-01

    Transforming growth factor-beta (TGFβ) signaling in cancer is context dependent and acts either as a tumor suppressor or a tumor promoter. Loss of function mutation in TGFβ type II receptor (TβRII) is a frequent event in oral cavity squamous cell carcinoma (SCC). Recently, heterogeneity of TGFβ response has been described at the leading edge of SCC and this heterogeneity has been shown to influence stem cell renewal and drug resistance. Because exosome transfer from stromal to breast cancer cells regulates therapy resistance pathways we investigated whether exosomes contain components of the TGFβ signaling pathway and whether exosome transfer between stromal fibroblasts and tumor cells can influence TGFβ signaling in SCC. We demonstrate that exosomes purified from stromal fibroblasts isolated from patients with oral SCC contains TβRII. We also demonstrate that transfer of fibroblast exosomes increases TGFβ signaling in SCC keratinocytes devoid of TβRII which remain non-responsive to TGFβ ligand in the absence of exosome transfer. Overall our data show that stromal communication with tumor cells can direct TGFβ signaling in SCC. PMID:27347352

  13. 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.

  14. T-Cell Tumor Elimination as a Result of T-Cell Receptor-Mediated Activation

    Science.gov (United States)

    Ashwell, Jonathan D.; Longo, Dan L.; Bridges, Sandra H.

    1987-07-01

    It has recently been shown that activation of murine T-cell hybridomas with antigen inhibits their growth in vitro. The ``suicide'' of these neoplastic T cells upon stimulation with antigen suggested the possibility that activation via the antigen-specific receptor could also inhibit the growth of neoplastic T cells in vivo. To test this, mice were subcutaneously inoculated with antigen-specific T-cell hybridomas and then treated intraperitoneally with antigen. Administration of the appropriate antigen immediately after inoculation with the T-cell hybridoma abrogated tumor formation; antigen administered after tumors had become established decreased the tumor burden and, in a substantial fraction of animals, led to long-term survival. The efficacy of antigen therapy was due to both a direct inhibitory effect on tumor growth and the induction of host immunity. These studies demonstrate the utility of cellular activation as a means of inhibiting neoplastic T-cell growth in vivo and provide a rationale for studying the use of less selective reagents that can mimic the activating properties of antigen, such as monoclonal antibodies, in the treatment of T-cell neoplasms of unknown antigen specificity.

  15. Dendritic cell based immunotherapy using tumor stem cells mediates potent antitumor immune responses.

    Science.gov (United States)

    Dashti, Amir; Ebrahimi, Marzieh; Hadjati, Jamshid; Memarnejadian, Arash; Moazzeni, Seyed Mohammad

    2016-04-28

    Cancer stem cells (CSCs) are demonstrated to be usually less sensitive to conventional methods of cancer therapies, resulting in tumor relapse. It is well-known that an ideal treatment would be able to selectively target and kill CSCs, so as to avoid the tumor reversion. The aim of our present study was to evaluate the effectiveness of a dendritic cell (DC) based vaccine against CSCs in a mouse model of malignant melanoma. C57BL/6 mouse bone marrow derived DCs pulsed with a murine melanoma cell line (B16F10) or CSC lysates were used as a vaccine. Immunization of mice with CSC lysate-pulsed DCs was able to induce a significant prophylactic effect by a higher increase in lifespan and obvious depression of tumor growth in tumor bearing mice. The mice vaccinated with DCs loaded with CSC-lysate were revealed to produce specific cytotoxic responses to CSCs. The proliferation assay and cytokine (IFN-γ and IL-4) secretion of mice vaccinated with CSC lysate-pulsed DCs also showed more favorable results, when compared to those receiving B16F10 lysate-pulsed DCs. These findings suggest a potential strategy to improve the efficacy of DC-based immunotherapy of cancers. PMID:26803056

  16. 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.

  17. 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.

  18. 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.

  19. 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

  20. Protein Delivery of Thymidylate Kinase Mediated by Tumor-Specific Antibody-Precoated Microvesicles.

    Science.gov (United States)

    Mohammadzadeh-Vardin, Mohammad; Panahpour, Hamdollah; Golmohammadi, Mohammad Ghasem; Sagha, Mohsen

    2016-01-01

    Molecular targeted therapy is an important, novel approach in the treatment of cancer because it interferes with certain molecules involved in carcinogenesis and tumor growth. Examples include monoclonal antibodies, microvesicles, and suicide genes. Several studies have focused on targeted therapies in prostate cancer, which is a serious cause of cancer death in men. We hypothesize that antibody-coated microvesicles can deliver thymidylate kinase, a suicide protein, to prostate cancer cells, potentiating them to death following azidothymidine (AZT) treatment. PMID:27278881

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

    OpenAIRE

    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 metabo...

  2. Sigma receptor-mediated targeted delivery of anti-angiogenic multifunctional nanodrugs for combination tumor therapy.

    Science.gov (United States)

    Li, Yuanke; Wu, Yuanyuan; Huang, Leaf; Miao, Lei; Zhou, Jianping; Satterlee, Andrew Benson; Yao, Jing

    2016-04-28

    The potential of low molecular weight heparin (LMWH) in anti-angiogenic therapy has been tempered by poor in vivo delivery to the tumor cell and potentially harmful side effects, such as the risk of bleeding due to heparin's anticoagulant activity. In order to overcome these limitations and further improve the therapeutic effect of LMWH, we designed a novel combination nanosystem of LMWH and ursolic acid (UA), which is also an angiogenesis inhibitor for tumor therapy. In this system, an amphiphilic LMWH-UA (LHU) conjugate was synthesized and self-assembled into core/shell nanodrugs with combined anti-angiogenic activity and significantly reduced anticoagulant activity. Furthermore, DSPE-PEG-AA-modified LHU nanodrugs (A-LHU) were developed to facilitate the delivery of nanodrugs to the tumor. The anti-angiogenic activity of A-LHU was investigated both in vitro and in vivo. It was found that A-LHU significantly inhibited the tubular formation of human umbilical vein endothelial cells (HUVECs) (pnanodrugs are a promising multifunctional antitumor drug delivery system. PMID:26941036

  3. 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.

  4. Multi-functionalized hyaluronic acid nanogels crosslinked with carbon dots as dual receptor-mediated targeting tumor theranostics.

    Science.gov (United States)

    Jia, Xu; Han, Yu; Pei, Mingliang; Zhao, Xubo; Tian, Kun; Zhou, Tingting; Liu, Peng

    2016-11-01

    Hyaluronic acid (HA)-based theranostic nanogels were designed for the tumor diagnosis and chemotherapy, by crosslinking the folate-terminated poly(ethylene glycol) modified hyaluronic acid (FA-PEG-HA) with carbon dots (CDs) for the first time. Due to the extraordinary fluorescence property of the integrated CDs, the theranostic nanogels could be used for the real-time and noninvasive location tracking to cancer cells. HA could load Doxorubicin (DOX) via electrostatic interaction with a drug-loading capacity (DLC) of 32.5%. The nanogels possessed an ideal release of DOX in the weak acid environment, while it was restrained in the neutral media, demonstrating the pH-responsive controlled release behavior. The cytotoxicity and cellular uptake results clearly illustrated that most DOX was released and accumulated in the cell nuclei and killed the cancer cells efficaciously, due to their dual receptor-mediated targeting characteristics. PMID:27516286

  5. 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/).

  6. Downregulation of adenine nucleotide translocator 1 exacerbates tumor necrosis factor-α-mediated cardiac inflammatory responses

    OpenAIRE

    Pan, Shi; Wang, Nadan; Bisetto, Sara; Yi, Bing; Sheu, Shey-Shing

    2014-01-01

    Inflammation contributes significantly to cardiac dysfunction. Although the initial phase of inflammation is essential for repair and healing, excessive proinflammatory cytokines are detrimental to the heart. We found that adenine nucleotide translocator isoform-1 (ANT1) protein levels were significantly decreased in the inflamed heart of C57BL/6 mice following cecal ligation and puncture. To understand the molecular mechanisms involved, we performed small-interfering RNA-mediated knockdown o...

  7. Enhancement of p53 gene transfer efficiency in hepatic tumor mediated by transferrin receptor through trans-arterial delivery.

    Science.gov (United States)

    Lu, Qin; Teng, Gao-Jun; Zhang, Yue; Niu, Huan-Zhang; Zhu, Guang-Yu; An, Yan-Li; Yu, Hui; Li, Guo-Zhao; Qiu, Ding-Hong; Wu, Chuan-Ging

    2008-02-01

    Transferrin-DNA complex mediated by transferrin receptor in combination with interventional trans-arterial injection into a target organ may be a duel-target-oriented delivery means to achieve an efficient gene therapy. In this study, transferrin receptor expression in normal human hepatocyte and two hepatocellular-carcinoma cells (Huh7/SK-Hep1) was determined. p53-LipofectAMINE with different amounts of transferrin was transfected into the cells and the gene transfection efficiency was evaluated. After VX2 rabbit hepatocarcinoma model was established, the transferrin-p53-LipofectAMINE complex was delivered into the hepatic artery via interventional techniques to analyze the therapeutic p53 gene transfer efficiency in vivo by Western blot, immunohistochemical/immunofluorescence staining analysis and survival time. The results were transferrin receptor expression in Huh7 and SK-Hep1 cells was higher than in normal hepatocyte. Transfection efficiency of p53 was increased in vitro in both Huh7 and SK-Hep1 cells with increasing transferrin in a dose-dependent manner. As compared to intravenous administration, interventional injection of p53-gene complex into hepatic tumor mediated by transferrin-receptor, could enhance the gene transfer efficiency in vivo as evaluated by Western blot, immunohistochemical/immunofluorenscence staining analyses and improved animal survival (H = 12.567, p = 0.0019). These findings show the transferrin-transferrin receptor system combined with interventional techniques enhanced p53-gene transfer to hepatic tumor and the duel-target-oriented gene delivery may be an effective approach for gene therapy. PMID:18347429

  8. Surface expressed nucleolin is constantly induced in tumor cells to mediate calcium-dependent ligand internalization.

    Directory of Open Access Journals (Sweden)

    Ara G Hovanessian

    Full Text Available BACKGROUND: Nucleolin is one of the major proteins of the nucleolus, but it is also expressed on the cell surface where is serves as a binding protein for variety of ligands implicated in tumorigenesis and angiogenesis. Emerging evidence suggests that the cell-surface expressed nucleolin is a strategic target for an effective and nontoxic cancer therapy. METHODOLOGY/PRINCIPAL FINDINGS: By monitoring the expression of nucleolin mRNA, and by measuring the level of nucleolin protein recovered from the surface and nucleus of cells, here we show that the presence of nucleolin at the cell surface is dependent on the constant induction of nucleolin mRNA. Indeed, inhibitors of RNA transcription or translation block expression of surface nucleolin while no apparent effect is observed on the level of nucleolin in the nucleus. The estimated half-life of surface nucleolin is less than one hour, whereas that of nuclear nucleolin is more than 8 hours. Nucleolin mRNA induction is reduced markedly in normal fibroblasts that reach confluence, while it occurs continuously even in post-confluent epithelial tumor cells consistent with their capacity to proliferate without contact inhibition. Interestingly, cold and heat shock induce nucleolin mRNA concomitantly to enhanced mRNA expression of the heat shock protein 70, thus suggesting that surface nucleolin induction also occurs in response to an environmental insult. At the cell surface, one of the main functions of nucleolin is to shuttle specific extracellular ligands by an active transport mechanism, which we show here to be calcium dependent. CONCLUSION/SIGNIFICANCE: Our results demonstrate that the expression of surface nucleolin is an early metabolic event coupled with tumor cell proliferation and stress response. The fact that surface nucleolin is constantly and abundantly expressed on the surface of tumor cells, makes them a preferential target for the inhibitory action of anticancer agents that target

  9. 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...

  10. Elevated CDCP1 predicts poor patient outcome and mediates ovarian clear cell carcinoma by promoting tumor spheroid formation, cell migration and chemoresistance.

    Science.gov (United States)

    He, Y; Wu, A C; Harrington, B S; Davies, C M; Wallace, S J; Adams, M N; Palmer, J S; Roche, D K; Hollier, B G; Westbrook, T F; Hamidi, H; Konecny, G E; Winterhoff, B; Chetty, N P; Crandon, A J; Oliveira, N B; Shannon, C M; Tinker, A V; Gilks, C B; Coward, J I; Lumley, J W; Perrin, L C; Armes, J E; Hooper, J D

    2016-01-28

    Hematogenous metastases are rarely present at diagnosis of ovarian clear cell carcinoma (OCC). Instead dissemination of these tumors is characteristically via direct extension of the primary tumor into nearby organs and the spread of exfoliated tumor cells throughout the peritoneum, initially via the peritoneal fluid, and later via ascites that accumulates as a result of disruption of the lymphatic system. The molecular mechanisms orchestrating these processes are uncertain. In particular, the signaling pathways used by malignant cells to survive the stresses of anchorage-free growth in peritoneal fluid and ascites, and to colonize remote sites, are poorly defined. We demonstrate that the transmembrane glycoprotein CUB-domain-containing protein 1 (CDCP1) has important and inhibitable roles in these processes. In vitro assays indicate that CDCP1 mediates formation and survival of OCC spheroids, as well as cell migration and chemoresistance. Disruption of CDCP1 via silencing and antibody-mediated inhibition markedly reduce the ability of TOV21G OCC cells to form intraperitoneal tumors and induce accumulation of ascites in mice. Mechanistically our data suggest that CDCP1 effects are mediated via a novel mechanism of protein kinase B (Akt) activation. Immunohistochemical analysis also suggested that CDCP1 is functionally important in OCC, with its expression elevated in 90% of 198 OCC tumors and increased CDCP1 expression correlating with poor patient disease-free and overall survival. This analysis also showed that CDCP1 is largely restricted to the surface of malignant cells where it is accessible to therapeutic antibodies. Importantly, antibody-mediated blockade of CDCP1 in vivo significantly increased the anti-tumor efficacy of carboplatin, the chemotherapy most commonly used to treat OCC. In summary, our data indicate that CDCP1 is important in the progression of OCC and that targeting pathways mediated by this protein may be useful for the management of OCC

  11. 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.

  12. 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.

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

    International Nuclear Information System (INIS)

    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

  14. MCT1-mediated transport of a toxic molecule is an effective strategy for targeting glycolytic tumors.

    Science.gov (United States)

    Birsoy, Kivanç; Wang, Tim; Possemato, Richard; Yilmaz, Omer H; Koch, Catherine E; Chen, Walter W; Hutchins, Amanda W; Gultekin, Yetis; Peterson, Tim R; Carette, Jan E; Brummelkamp, Thijn R; Clish, Clary B; Sabatini, David M

    2013-01-01

    There is increasing evidence that oncogenic transformation modifies the metabolic program of cells. A common alteration is the upregulation of glycolysis, and efforts to target glycolytic enzymes for anticancer therapy are under way. Here, we performed a genome-wide haploid genetic screen to identify resistance mechanisms to 3-bromopyruvate (3-BrPA), a drug candidate that inhibits glycolysis in a poorly understood fashion. We identified the SLC16A1 gene product, MCT1, as the main determinant of 3-BrPA sensitivity. MCT1 is necessary and sufficient for 3-BrPA uptake by cancer cells. Additionally, SLC16A1 mRNA levels are the best predictor of 3-BrPA sensitivity and are most elevated in glycolytic cancer cells. Furthermore, forced MCT1 expression in 3-BrPA-resistant cancer cells sensitizes tumor xenografts to 3-BrPA treatment in vivo. Our results identify a potential biomarker for 3-BrPA sensitivity and provide proof of concept that the selectivity of cancer-expressed transporters can be exploited for delivering toxic molecules to tumors. PMID:23202129

  15. SIRT2-Mediated Deacetylation and Tetramerization of Pyruvate Kinase Directs Glycolysis and Tumor Growth.

    Science.gov (United States)

    Park, Seong-Hoon; Ozden, Ozkan; Liu, Guoxiang; Song, Ha Yong; Zhu, Yueming; Yan, Yufan; Zou, Xianghui; Kang, Hong-Jun; Jiang, Haiyan; Principe, Daniel R; Cha, Yong-Il; Roh, Meejeon; Vassilopoulos, Athanassios; Gius, David

    2016-07-01

    Sirtuins participate in sensing nutrient availability and directing metabolic activity to match energy needs with energy production and consumption. However, the pivotal targets for sirtuins in cancer are mainly unknown. In this study, we identify the M2 isoform of pyruvate kinase (PKM2) as a critical target of the sirtuin SIRT2 implicated in cancer. PKM2 directs the synthesis of pyruvate and acetyl-CoA, the latter of which is transported to mitochondria for use in the Krebs cycle to generate ATP. Enabled by a shotgun mass spectrometry analysis founded on tissue culture models, we identified a candidate SIRT2 deacetylation target at PKM2 lysine 305 (K305). Biochemical experiments including site-directed mutants that mimicked constitutive acetylation suggested that acetylation reduced PKM2 activity by preventing tetramerization to the active enzymatic form. Notably, ectopic overexpression of a deacetylated PKM2 mutant in Sirt2-deficient mammary tumor cells altered glucose metabolism and inhibited malignant growth. Taken together, our results argued that loss of SIRT2 function in cancer cells reprograms their glycolytic metabolism via PKM2 regulation, partially explaining the tumor-permissive phenotype of mice lacking Sirt2 Cancer Res; 76(13); 3802-12. ©2016 AACR. PMID:27197174

  16. Characteristics of magnetic labeling on liver tumors with anti-alpha-fetoprotein-mediated Fe3O4 magnetic nanoparticles

    Directory of Open Access Journals (Sweden)

    Huang KW

    2012-06-01

    Full Text Available Kai-Wen Huang,1 Jen-Jie Chieh,2 Herng-Er Horng,2 Chin-Yih Hong,3 Hong-Chang Yang41Department of Surgery and Hepatitis Research Center, National Taiwan University Hospital, Taipei, 2Institute of Electro-optical Science and Technology, National Taiwan Normal University, Taipei, 3Graduate Institute of Biomedical Engineering, National Chung Hsing University, Taichung, 4Department of Physics, National Taiwan University, Taipei, TaiwanAbstract: For preoperative and intraoperative detection of tumor distribution, numerous multimodal contrast agents, such as magnetic nanoparticles (MNPs with several examination indicators, are currently in development. However, complex materials, configuration, and cost are required for multimodal contrast agents, accompanied by a high possibility of toxicity and low popularity in clinics. Nevertheless, the magnetic labeling of MNPs using bioprobes should be feasible not only in preoperative magnetic resonance imaging (MRI, but also in intraoperative examination based on other magnetic properties. In this study, anti-alpha-fetoprotein (AFP-mediated Fe3O4 MNPs, injected into mice with liver tumors, were used to examine the characteristics of magnetic labeling. Using MRI and scanning superconducting-quantum-interference-device biosusceptometry (SSB, based on alternating current (AC susceptibility, the magnetic labeling occurred significantly on the first day post-injection of anti-AFP magnetic fluid (MF, and then decreased over time. However, for both MF without antibodies and an anti-carcinoembryonic antigen MF, no magnetic labeling occured on the first day of their respective post-injection. The favorable agreement indicates that magnetic labeling possesses two magnetic characteristics: distortion of the imaging field and AC susceptibility. In addition, the results of the biopsy tests, anti-AFP staining, and Prussian blue staining show the same dynamics as those of magnetic methodologies and prove that bound MNPs on

  17. A panel of tumor markers, calreticulin, annexin A2, and annexin A3 in upper tract urothelial carcinoma identified by proteomic and immunological analysis

    International Nuclear Information System (INIS)

    Upper tract urothelial carcinoma (UTUC) is a tumor with sizable metastases and local recurrence. It has a worse prognosis than bladder cancer. This study was designed to investigate the urinary potential tumor markers of UTUC. Between January 2008 and January 2009, urine was sampled from 13 patients with UTUC and 20 healthy adults. The current study identified biomarkers for UTUC using non-fixed volume stepwise weak anion exchange chromatography for fractionation of urine protein prior to two-dimensional gel electrophoresis. Fifty five differential proteins have been determined by comparing with the 2-DE maps of the urine of UTUC patients and those of healthy people. Western blotting analysis and immunohistochemistry of tumor tissues and normal tissues from patients with UTUC were carried out to further verify five possible UTUC biomarkers, including zinc-alpha-2-glycoprotein, calreticulin, annexin A2, annexin A3 and haptoglobin. The data of western blot and immunohistochemical analysis are consistent with the 2-DE data. Combined the experimental data in the urine and in tumor tissues collected from patients with UTUC, the crucial over-expressed proteins are calreticulin, annexin A2, and annexin A3. Calreticulin, annexin A2, and annexin A3 are very likely a panel of biomarkers with potential value for UTUC diagnosis

  18. Rapid alternative to the clonogenic assay for measuring antibody and complement-mediated killing of tumor cells

    International Nuclear Information System (INIS)

    A study of the methods used to quantitate killing of tumor cells by antibody and complement has highlighted a number of problems. Using leukemia as a model, the authors have found that the release of 51Cr from labeled tumor cells treated with antibody and complement can be an equivocal measure of cell viability. Combined with its restricted sensitivity (less than a 2 log range of cell killing) this makes this widely used assay of questionable value for detecting small numbers of viable cells, or for identifying subpopulations of complement-resistant cells. As an alternative a [125I]iododeoxyuridine uptake assay has been developed, that combines the simplicity and rapidity of the 51Cr release technique with the sensitivity of a clonogenic assay. This method eliminates the problem of spontaneous isotope release, inherent in prelabeling assays, and variability from experiment to experiment can be avoided by including a viable cell standard curve within each assay. The sensitivity of the 125IUdR uptake method, which can be completed within a day, is similar to that of a 10 day methylcellulose cloning assay and was capable of detecting the presence of a minor subpopulation of complement-resistant tumor cells

  19. 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

  20. 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

  1. 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

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

    International Nuclear Information System (INIS)

    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 amphiphilic

  3. 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

    Daratumumab (DARA) is a human CD38-specific IgG1 antibody that is in clinical development for the treatment of multiple myeloma (MM). The potential for IgG1 antibodies to induce macrophage-mediated phagocytosis, in combination with the known presence of macrophages in the tumor microenvironment i...

  4. 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.

  5. A Novel Extracellular Hsp90 Mediated Co-Receptor Function for LRP1 Regulates EphA2 Dependent Glioblastoma Cell Invasion

    OpenAIRE

    Udhayakumar Gopal; Bohonowych, Jessica E.; Carla Lema-Tome; Angen Liu; Elizabeth Garrett-Mayer; Bingcheng Wang; Isaacs, Jennifer S.

    2011-01-01

    BACKGROUND: Extracellular Hsp90 protein (eHsp90) potentiates cancer cell motility and invasion through a poorly understood mechanism involving ligand mediated function with its cognate receptor LRP1. Glioblastoma multiforme (GBM) represents one of the most aggressive and lethal brain cancers. The receptor tyrosine kinase EphA2 is overexpressed in the majority of GBM specimens and is a critical mediator of GBM invasiveness through its AKT dependent activation of EphA2 at S897 (P-EphA2(S897)). ...

  6. 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.

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

    Science.gov (United States)

    Kurayoshi, Kenta; Ozono, Eiko; Iwanaga, Ritsuko; Bradford, Andrew P; Komori, Hideyuki; Ohtani, Kiyoshi

    2014-07-18

    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 is activated by E2F only in cancer cells and therefore may be more cancer cell-specific than E2F1 promoter to drive gene expression. We show here that the ARF promoter has lower activity in normal growing fibroblasts and shows higher cancer cell-specificity compared to the E2F1 promoter. We also demonstrate that adenovirus expressing HSV

  8. 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

  9. Anticoagulation inhibits tumor cell-mediated release of platelet angiogenic proteins and diminishes platelet angiogenic response.

    Science.gov (United States)

    Battinelli, Elisabeth M; Markens, Beth A; Kulenthirarajan, Rajesh A; Machlus, Kellie R; Flaumenhaft, Robert; Italiano, Joseph E

    2014-01-01

    Platelets are a reservoir for angiogenic proteins that are secreted in a differentially regulated process. Because of the propensity for clotting, patients with malignancy are often anticoagulated with heparin products, which paradoxically offer a survival benefit by an unknown mechanism. We hypothesized that antithrombotic agents alter the release of angiogenesis regulatory proteins from platelets. Our data revealed that platelets exposed to heparins released significantly decreased vascular endothelial growth factor (VEGF) in response to adenosine 5'-diphosphate or tumor cells (MCF-7 cells) and exhibited a decreased angiogenic potential. The releasate from these platelets contained decreased proangiogenic proteins. The novel anticoagulant fondaparinux (Xa inhibitor) demonstrated a similar impact on the platelet angiogenic potential. Because these anticoagulants decrease thrombin generation, we hypothesized that they disrupt signaling through the platelet protease-activated receptor 1 (PAR1) receptor. Addition of PAR1 antagonists to platelets decreased VEGF release and angiogenic potential. Exposure to a PAR1 agonist in the presence of anticoagulants rescued the angiogenic potential. In vivo studies demonstrated that platelets from anticoagulated patients had decreased VEGF release and angiogenic potential. Our data suggest that the mechanism by which antithrombotic agents increase survival and decrease metastasis in cancer patients is through attenuation of platelet angiogenic potential. PMID:24065244

  10. Structurally novel steroidal spirooxindole by241 potently inhibits tumor growth mainly through ROS-mediated mechanisms.

    Science.gov (United States)

    Shi, Xiao-Jing; Yu, Bin; Wang, Jun-Wei; Qi, Ping-Ping; Tang, Kai; Huang, Xin; Liu, Hong-Min

    2016-01-01

    Cancer cells always have increased ROS levels, thus making them more vulnerable to persistent endogenous oxidative stress. The biochemical difference between cancer and normal cells could be exploited to achieve selective cancer cell killing by exogenous ROS-producing agents. Herein we described a structurally novel steroidal spirooxindole by241 and its anticancer efficacy. By241 exhibited potent inhibition against human cancer cells and less toxic to normal cells. By241 concentration-dependently induced apoptosis of MGC-803 and EC9706 cells, accompanied with the mitochondrial dysfunction and increased ROS levels. NAC can completely restore the decreased cell viability of MGC-803 cells caused by by241, suggesting ROS-mediated mechanisms. The expression levels of proteins involved in the mitochondrion-related pathways were detected, showing increased expression of proapoptotic proteins and decreased expression of anti-apoptotic proteins, and activation of caspases-9/-3, but without activating caspase-8 expression. Pretreatment with Z-VAD-FMK partially rescued by241-induced apoptosis of MGC-803 cells. Additionally, by241 inhibited mTOR, activated p53 and its downstream proteins, cleaved MDM2 and PI3K/AKT as well as NF-κB signaling pathway. In vivo experiments showed that by241 did not have significant acute oral toxicity and exerted good anticancer efficacy against MGC-803 bearing mice models. Therefore, by241 may serve as a lead for further development for cancer therapy. PMID:27527552

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

    International Nuclear Information System (INIS)

    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

  12. 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

  13. 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.

  14. 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.

  15. 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.

  16. Inflammatory cytokine tumor necrosis factor α suppresses neuroprotective endogenous erythropoietin from astrocytes mediated by hypoxia-inducible factor-2α.

    Science.gov (United States)

    Nagaya, Yoshiaki; Aoyama, Mineyoshi; Tamura, Tetsuya; Kakita, Hiroki; Kato, Shin; Hida, Hideki; Saitoh, Shinji; Asai, Kiyofumi

    2014-12-01

    Interest in erythropoietin (EPO) as a neuroprotective mediator has grown since it was found that systemically administered EPO is protective in several animal models of disease. However, given that the blood-brain barrier limits EPO entry into the brain, alternative approaches that induce endogenous EPO production in the brain may be more effective clinically and associated with fewer untoward side-effects. Astrocytes are the main source of EPO in the central nervous system. In the present study we investigated the effect of the inflammatory cytokine tumor necrosis factor α (TNFα) on hypoxia-induced upregulation of EPO in rat brain. Hypoxia significantly increased EPO mRNA expression in the brain and kidney, and this increase was suppressed by TNFα in vivo. In cultured astrocytes exposed to hypoxic conditions for 6 and 12 h, TNFα suppressed the hypoxia-induced increase in EPO mRNA expression in a concentration-dependent manner. TNFα inhibition of hypoxia-induced EPO expression was mediated primarily by hypoxia-inducible factor (HIF)-2α rather than HIF-1α. The effects of TNFα in reducing hypoxia-induced upregulation of EPO mRNA expression probably involve destabilization of HIF-2α, which is regulated by the nuclear factor (NF)-κB signaling pathway. TNFα treatment attenuated the protective effects of astrocytes on neurons under hypoxic conditions via EPO signaling. The effective blockade of TNFα signaling may contribute to the maintenance of the neuroprotective effects of EPO even under hypoxic conditions with an inflammatory response. PMID:25283246

  17. 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.

  18. 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. PMID:25999791

  19. 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.

  20. 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

  1. 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

    OpenAIRE

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

    2011-01-01

    Abstract Background 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. Methods Combined gene therapy strategy with recombinant adenovirus expressing horseradish peroxidase (HRP) mediated by human telomerase reverse transcriptase (hTERT) promoter (AdhTERTHRP) and murine int...

  2. 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

  3. 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.

  4. Treatment of tumors with vitamin E suppresses myeloid derived suppressor cells and enhances CD8+ T cell-mediated antitumor effects.

    Directory of Open Access Journals (Sweden)

    Tae Heung Kang

    Full Text Available Vitamin E has been shown to have strong anticarcinogenic properties, including antioxidant characteristics, making it an ideal candidate for use in combination with immunotherapies that modify the tumor microenvironment. The tumor microenvironment contains immunosuppressive components, which can be diminished, and immunogenic components, which can be augmented by immunotherapies in order to generate a productive immune response. In the current study, we employ the α-tocopherol succinate isomer of vitamin E to reduce immunosuppression by myeloid derived suppressor cells (MDSCs as well as adoptive transfer of antigen-specific CD8+ T cells to generate potent antitumor effects against the HPV16 E7-expressing TC-1 tumor model. We show that vitamin E alone induces necrosis of TC-1 cells and elicits antitumor effects in TC-1 tumor-bearing mice. We further demonstrate that vitamin E reverses the suppression of T cell activation by MDSCs and that this effect is mediated in part by a nitric oxide-dependent mechanism. Additionally, treatment with vitamin E reduces the percentage of MDSCs in tumor loci, and induces a higher percentage of T cells, following T cell adoptive transfer. Finally, we demonstrate that treatment with vitamin E followed by E7-specific T cell adoptive transfer experience elicits potent antitumor effects in tumor-bearing mice. Our data provide additional evidence that vitamin E has anticancer properties and that it has promise for use as an adjuvant in combination with a variety of cancer therapies.

  5. 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…

  6. P-Selectin-Mediated Adhesion between Platelets and Tumor Cells Promotes Intestinal Tumorigenesis in ApcMin/+ Mice

    OpenAIRE

    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, a...

  7. 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.

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

    Directory of Open Access Journals (Sweden)

    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

  9. TRIADIMEFON INDUCES RAT THYROID TUMORS THROUGH A NON-TSH MEDIATED MODE OF ACTION

    Science.gov (United States)

    Conazoles are a class of fungicides used as agricultural and pharmaceutical products which inhibit ergosterol biosynthesis. Members of this class are hepatotoxic and cause mouse hepatocellular tumors and/or rat thyroid follicular cell tumors. Triadimefon-induced rat thyroid tumor...

  10. 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.

  11. 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.

  12. Dual anti-OX40/IL-2 therapy augments tumor immunotherapy via IL-2R-mediated regulation of OX40 expression.

    Directory of Open Access Journals (Sweden)

    William L Redmond

    Full Text Available The provision of T cell co-stimulation via members of the TNFR super-family, including OX40 (CD134 and 4-1BB (CD137, provides critical signals that promote T cell survival and differentiation. Recent studies have demonstrated that ligation of OX40 can augment T cell-mediated anti-tumor immunity in pre-clinical models and more importantly, OX40 agonists are under clinical development for cancer immunotherapy. OX40 is of particular interest as a therapeutic target as it is not expressed on naïve T cells but rather, is transiently up-regulated following TCR stimulation. Although TCR engagement is necessary for inducing OX40 expression, the downstream signals that regulate OX40 itself remain unclear. In this study, we demonstrate that OX40 expression is regulated through a TCR and common gamma chain cytokine-dependent signaling cascade that requires JAK3-mediated activation of the downstream transcription factors STAT3 and STAT5. Furthermore, combined treatment with an agonist anti-OX40 mAb and IL-2 augmented tumor immunotherapy against multiple tumor types. Dual therapy was also able to restore the function of anergic tumor-reactive CD8 T cells in mice with long-term well-established (>5 wks tumors, leading to increased survival of the tumor-bearing hosts. Together, these data reveal the ability of TCR/common gamma chain cytokine signaling to regulate OX40 expression and demonstrate a novel means of augmenting cancer immunotherapy by providing dual anti-OX40/common gamma chain cytokine-directed therapy.

  13. 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.

  14. Functionalized graphene oxide mediated adriamycin delivery and miR-21 gene silencing to overcome tumor multidrug resistance in vitro.

    Directory of Open Access Journals (Sweden)

    Feng Zhi

    Full Text Available Multidrug resistance (MDR is a major impediment to successful cancer chemotherapy. Co-delivery of novel MDR-reversing agents and anticancer drugs to cancer cells holds great promise for cancer treatment. MicroRNA-21 (miR-21 overexpression is associated with the development and progression of MDR in breast cancer, and it is emerging as a novel and promising MDR-reversing target. In this study, a multifunctional nanocomplex, composed of polyethylenimine (PEI/poly(sodium 4-styrenesulfonates (PSS/graphene oxide (GO and termed PPG, was prepared using the layer-by-layer assembly method to evaluate the reversal effects of PPG as a carrier for adriamycin (ADR along with miR-21 targeted siRNA (anti-miR-21 in cancer drug resistance. ADR was firstly loaded onto the PPG surface (PPGADR by physical mixing and anti-miR-21 was sequentially loaded onto PPGADR through electric absorption to form (anti-miR-21PPGADR. Cell experiments showed that PPG significantly enhanced the accumulation of ADR in MCF-7/ADR cells (an ADR resistant breast cancer cell line and exhibited much higher cytotoxicity than free ADR, suggesting that PPG could effectively reverse ADR resistance of MCF-7/ADR. Furthermore, the enhanced therapeutic efficacy of PPG could be correlated with effective silencing of miR-21 and with increased accumulation of ADR in drug-resistant tumor cells. The endocytosis study confirmed that PPG could effectively carry drug molecules into cells via the caveolae and clathrin-mediated endocytosis pathways. These results suggest that this PPG could be a potential and efficient non-viral vector for reversing MDR, and the strategy of combining anticancer drugs with miRNA therapy to overcome MDR could be an attractive approach in cancer treatment.

  15. Anti-tumor effect of adenovirus-mediated suicide gene therapy under control of tumor-specific and radio-inducible chimeric promoter in combination with γ-ray irradiation in vivo

    International Nuclear Information System (INIS)

    Objective: To detect the selective inhibitory effects of irradiation plus adenovirus-mediated horseradish peroxidase (HRP)/indole-3-acetic acid (IAA) suicide gene system using tumor-specific and radio-inducible chimeric promoter on human hepatocellular carcinoma subcutaneously xenografted in nude mouse. Methods: Recombinant replicated-deficient adenovirus vector containing HRP gene and chimeric human telomerase reverse transcriptase (hTERT) promoter carrying 6 radio-inducible CArG elements was constructed. A human subcutaneous transplanting hepatocellular carcinoma (MHCC97 cell line) model was treated with γ-ray irradiation plus intra-tumor injections of adenoviral vector and intra-peritoneal injections of prodrug IAA. The change of tumor volume and tumor growth inhibiting rate, the survival time of nude mice, as well as histopathology of xenograft tumor and normal tissues were evaluated. Results: Thirty one days after the treatment, the relative tumor volumes in the negative, adenovirus therapy, irradiation, and combination groups were 49.23±4.55, 27.71±7.74, 28.53±10.48 and 11.58±3.23, respectively.There was a significantly statistical difference among them (F=16.288, P<0.01).The inhibition effect in the combination group was strongest as compared with that in other groups, and its inhibition ratio was 76.5%. The survival period extended to 43 d in the combination group, which showed a significantly difference with that in the control group (χ2=18.307, P<0.01). The area of tumors necrosis in the combination group was larger than that in the other groups, and the normal tissues showed no treatment-related toxic effect in all groups. However, multiple hepatocellular carcinoma metastases were observed in the liver in the control group, there were a few metastases in the monotherapy groups and no metastasis in the combination group. Conclusions: Adenovirus-mediated suicide gene therapy plus radiotherapy dramatically could inhibit tumor growth and prolong median

  16. CD103 deficiency prevents graft-versus-host disease but spares graft-versus-tumor effects mediated by alloreactive CD8 T cells.

    Directory of Open Access Journals (Sweden)

    Kechang Liu

    Full Text Available BACKGROUND: Graft-versus-host disease (GVHD remains the main barrier to broader application of allogeneic hematopoietic stem cell transplantation (alloSCT as a curative therapy for host malignancy. GVHD is mediated by allogeneic T cells directed against histocompatibility antigens expressed by host tissues. Based on previous studies, we postulated that the integrin CD103 is required for CD8-mediated GVHD, but not for graft-versus-tumor effects (GVT. METHODOLOGY/PRINCIPAL FINDINGS: We herein provide evidence in support of this hypothesis. To circumvent the potentially confounding influence of donor CD4 T cells, we developed an alloSCT model in which GVHD mortality is mediated by purified CD8 T cells. In this model, host-reactive CD8 T cells receive CD4 T cell help at the time of initial activation but not in the effector phase in which mature CD8 T effectors migrate into host tissues. We show that donor CD8 T cells from wild-type BALB/c mice primed to host alloantigens induce GVHD pathology and eliminate tumors of host origin in the absence of host CD4 T cells. Importantly, CD103 deficiency dramatically attenuated GVHD mortality, but had no detectable impact on the capacity to eliminate a tumor line of host origin. We provide evidence that CD103 is required for accumulation of donor CD8 T cells in the host intestinal epithelium but not in the tumor or host lymphoid compartments. Consistent with these data, CD103 was preferentially expressed by CD8 T cells infiltrating the host intestinal epithelium but not by those infiltrating the tumor, lamina propria, or lymphoid compartments. We further demonstrate that CD103 expression is not required for classic CD8 effector activities including cytokine production and cytotoxicity. CONCLUSIONS/SIGNIFICANCE: These data indicate that CD103 deficiency inhibits GVHD pathology while sparing anti-tumor effects mediated by CD8 T cells, identifying CD103 blockade as an improved strategy for GVHD prophylaxis.

  17. 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.

  18. 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. PMID:26708213

  19. 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.

  20. Human uterus myoma and gene expression profiling: A novel in vitro model for studying secretory leukocyte protease inhibitor-mediated tumor invasion.

    Science.gov (United States)

    Mikami, Yoshikazu; Fukushima, Atsushi; Komiyama, Yusuke; Iwase, Takashi; Tsuda, Hiromasa; Higuchi, Yasuhiko; Hayakawa, Satoshi; Kuyama, Kayo; Komiyama, Kazuo

    2016-08-28

    Secretory leukocyte protease inhibitor (SLPI) is a serine protease inhibitor that diminishes tissue destruction during inflammation. A recent report revealed high levels of SLPI expression in the oral carcinoma cell. In addition, overexpression of SLPI up-regulates metastasis in lung carcinoma cells. On the other hand, matrix metalloproteinases (MMPs) are proteinases that participate in extracellular matrix degradation. SLPI and MMPs are involved as accelerators of the tumor invasion process; however, their exact roles are not fully understood. Understanding the mechanism of tumor invasion requires models that take the effect of microenvironmental factors into account. In one such in vitro model, different carcinoma cells have been shown to invade myoma tissue in highly distinct patterns. We have used this myoma model, as it provides a more natural stroma-like environment, to investigate the role of SLPI in tumor invasion. Our results indicate that the model provides a relevant matrix for tumor invasion studies, and that SLPI is important for the invasion of oral carcinoma Ca9-22 cells in conjunction with MMPs. Furthermore, using bioinformatics analysis, we have identified candidates as key molecules involved in SLPI-mediated tumor invasion. PMID:27238568

  1. 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.

  2. A hypoxia-induced decrease of either MICA/B or Hsp70 on the membrane of tumor cells mediates immune escape from NK cells.

    Science.gov (United States)

    Schilling, Daniela; Tetzlaff, Fabian; Konrad, Sarah; Li, Wei; Multhoff, Gabriele

    2015-01-01

    Recent findings suggest that hypoxia of the tumor microenvironment contributes to immune escape from natural killer (NK) cell-mediated cytotoxicity. Heat shock protein 70 (Hsp70) and the stress-regulated major histocompatibility class I chain-related protein A and B (MICA/B) both serve as ligands for activated NK cells when expressed on the cell surface of tumor cells. Herein, we studied the effects of hypoxia and hypoxia-inducible factor-1α (HIF-1α) on the membrane expression of these NK cell ligands in H1339 with high and MDA-MB-231 tumor cells with low basal HIF-1α levels and its consequences on NK cell-mediated cytotoxicity. We could show that a hypoxia-induced decrease in the membrane expression of MICA/B and Hsp70 on H1339 and MDA-MB-231 cells, respectively, is associated with a reduced sensitivity to NK cell-mediated lysis. A knockdown of HIF-1α revealed that the decreased surface expression of MICA/B under hypoxia is dependent on HIF-1α in H1339 cells with high basal HIF-1α levels. Hypoxia and HIF-1α did not affect the MICA/B expression in MDA-MB-231 cells but reduced the Hsp70 membrane expression which in turn also impaired NK cell recognition. Furthermore, we could show that the hypoxia-induced decrease in membrane Hsp70 is independent of HIF-1α in MDA-MB-231. Our data indicate that hypoxia-induced downregulation of both NK cell ligands MICA/B and Hsp70 impairs NK cell-mediated cytotoxicity, whereby only MICA/B appears to be regulated by HIF-1α.

  3. A High-avidity WT1-reactive T-Cell Receptor Mediates Recognition of Peptide and Processed Antigen but not Naturally Occurring WT1-positive Tumor Cells.

    Science.gov (United States)

    Jaigirdar, Adnan; Rosenberg, Steven A; Parkhurst, Maria

    2016-04-01

    Wilms tumor gene 1 (WT1) is an attractive target antigen for cancer immunotherapy because it is overexpressed in many hematologic malignancies and solid tumors but has limited, low-level expression in normal adult tissues. Multiple HLA class I and class II restricted epitopes have been identified in WT1, and multiple investigators are pursuing the treatment of cancer patients with WT1-based vaccines and adoptively transferred WT1-reactive T cells. Here we isolated an HLA-A*0201-restricted WT1-reactive T-cell receptor (TCR) by stimulating peripheral blood lymphocytes of healthy donors with the peptide WT1:126-134 in vitro. This TCR mediated peptide recognition down to a concentration of ∼0.1 ng/mL when pulsed onto T2 cells as well as recognition of HLA-A*0201 target cells transfected with full-length WT1 cDNA. However, it did not mediate consistent recognition of many HLA-A*0201 tumor cell lines or freshly isolated leukemia cells that endogeneously expressed WT1. We dissected this pattern of recognition further and observed that WT1:126-134 was more efficiently processed by immunoproteasomes compared with standard proteasomes. However, pretreatment of WT1 tumor cell lines with interferon gamma did not appreciably enhance recognition by our TCR. In addition, we highly overexpressed WT1 in several leukemia cell lines by electroporation with full-length WT1 cDNA. Some of these lines were still not recognized by our TCR suggesting possible antigen processing defects in some leukemias. These results suggest WT1:126-134 may not be a suitable target for T-cell based tumor immunotherapies. PMID:26938944

  4. 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.

  5. 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.

  6. 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.

  7. Preliminary study of MR diffusion weighted imaging in nude mice models of hepatic Bel7402 tumors after adenovirus-mediated cytosine diaminase-thymidine kinase gene therapy

    International Nuclear Information System (INIS)

    Objective: To study the characteristics of DWI in nude mice models of hepatic Bel7402 tumors after treatment with adenovirus-mediated cytosine diaminase-thymidine kinase (Ad. CD-TK) double suicide gene therapy, and then to identify whether DWI can be used for assessing curative effect of postoperative tumors. Methods: Thirty nude mice models of hepatic Bel7402 tumors were successfully created using cell suspension method, after the tumor grew to more than 1 cm in diameter, 20 tumor models were treated by intratumoral administration of Ad. CD-TK for 3 days plus intraperitonea (i.p.) treatment with 5-Fc and GCV for the duration of the study.Then they were randomly divided into three groups during 5-Fc and GCV treatment. The remaining 10 tumor models were used as controls. MR scanning were performed in 10th day before and after tumor implantation in all models by using EPI-SE series and SENSE technology for treatment group. Tumor volumes and ADC values were calculated pretreatment and posttreatment. Cell apoptosis were determined by using TUNEL method. Analyze the change of ADC and apoptosis index (AI) in different times, t test was used for comparison the difference of AI and ADC values respectively. Results: After 10 days,the tumor volumes of the treatment groups and controls were respectively (724.16 ±57.45) mm3, (754.57 ± 66.84) mm3, with no significant difference (t=0.488, P >0.05). The ADC values of the treatment groups were (0.98 ±0.11) × 10-3 mm2/s,the ones of the control groups were (0.68 ±0.04) × 10-3 mm2/s; AI of the treatment groups were (23.25 ±6.57)%, the ones of the control groups were (2.57 ± 0.58)%. There were difference in both groups (t=4.473, 5.874; P<0.01). Conclusion: DWI can be effectively to monitor the early pathological changes of hepatic Bel7402 tumors after Ad. CD-TK double suicide gene therapy, and provide experimental evidences for clinical application. (authors)

  8. The monoclonal antibody Zt/f2 targeting RON receptor tyrosine kinase as potential therapeutics against tumor growth-mediated by colon cancer cells

    Directory of Open Access Journals (Sweden)

    Zhang Rui-Wen

    2011-07-01

    Full Text Available Abstract Background Overexpression of the RON receptor tyrosine kinase contributes to epithelial cell transformation, malignant progression, and acquired drug resistance. RON also has been considered as a potential target for therapeutic intervention. This study determines biochemical features and inhibitory activity of a mouse monoclonal antibody (mAb Zt/f2 in experimental cancer therapy. Results Zt/f2 is a mouse IgG2a mAb that is highly specific and sensitive to human RON and its oncogenic variants such as RON160 (ED50 = 2.3 nmol/L. Receptor binding studies revealed that Zt/f2 interacts with an epitope(s located in a 49 amino acid sequence coded by exon 11 in the RON β-chain extracellular sequences. This sequence is critical in regulating RON maturation and phosphorylation. Zt/f2 did not compete with ligand macrophage-stimulating protein for binding to RON; however, its engagement effectively induced RON internalization, which diminishes RON expression and impairs downstream signaling activation. These biochemical features provide the cellular basis for the use of Zt/f2 to inhibit tumor growth in animal model. Repeated administration of Zt/f2 as a single agent into Balb/c mice results in partial inhibition of tumor growth caused by transformed NIH-3T3 cells expressing oncogenic RON160. Colon cancer HT-29 cell-mediated tumor growth in athymic nude mice also was attenuated following Zt/f2 treatment. In both cases, ~50% inhibition of tumor growth as measured by tumor volume was achieved. Moreover, Zt/f2 in combination with 5-fluorouracil showed an enhanced inhibition effect of ~80% on HT-29 cell-mediated tumor growth in vivo. Conclusions Zt/f2 is a potential therapeutic mAb capable of inhibiting RON-mediated oncogenesis by colon cancer cells in animal models. The inhibitory effect of Zt/f2 in vivo in combination with chemoagent 5-fluorouracil could represent a novel strategy for future colon cancer therapy.

  9. Fluorescence in vivo imaging of live tumor cells with pH-activatable targeted probes via receptor-mediated endocytosis

    Science.gov (United States)

    Asanuma, Daisuke; Urano, Yasuteru; Nagano, Tetsuo; Hama, Yukihiro; Koyama, Yoshinori; Kobayashi, Hisataka

    2009-02-01

    One goal of molecular imaging is to establish a widely applicable technique for specific detection of tumors with minimal background. Here, we achieve specific in vivo tumor visualization with a newly-designed "activatable" targeted fluorescence probe. This agent is activated after cellular internalization by sensing the pH change in the lysosome. Novel acidic pH-activatable probes based on the BODIPY fluorophore were synthesized, and then conjugated to a cancer-targeting monoclonal antibody, Trastuzumab, or galactosyl serum albumin (GSA). As proof of concept, ex and in vivo imaging of two different tumor mouse models was performed: HER2-overexpressed lung metastasis tumor with Trastuzumab-pH probe conjugates and lectin-overexpressed i.p. disseminated tumor with GSA-pH probe conjugates. These pH-activatable targeted probes were highly specific for tumors with minimal background signal. Because the acidic pH in lysosomes is maintained by the energy-consuming proton pump, only viable cancer cells were successfully visualized. Furthermore, this strategy was also applied to fluorescence endoscopy in tumor mouse models, resulting in specific visualization of tumors as small as submillimeter in size that could hardly detected by naked eyes because of their poor contrast against normal tissues. The design concept can be widely adapted to cancer-specific cell-surface-targeting molecules that result in cellular internalization.

  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. 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.

  12. 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

    p53 is upregulated in the majority of spontaneous tumors and the HLA class I molecule HLA-A2 is expressed by approximately 50% of the caucasians. Potentially, these facts make HLA-A2-binding p53 peptides for CTL-inducing immunotherapy applicable to a broad range of cancer patients. In our study, we...... investigated the CTL-inducing capacity of autologous monocyte-derived dendritic cells (DC) maturated by exposure to CD40L and pulsed with a pool of 4 wild-type, HLA-A2-binding p53 peptides, and the p53-specific CD8(+) CTL lines established from healthy HLA-A2-positive donors were characterized. Reactivity to p......53(65-73) and p53(187-197) peptides was obtained in the T-cell lines. Interestingly, cold target inhibition experiments demonstrated that the simultaneous recognition of the 2 peptides was the result of cross-reactivity, which was confirmed by killing experiments at the clonal CTL level. Furthermore...

  13. Landscape Phage Fusion Protein-mediated Targeting of Nanomedicines Enhances their Prostate Tumor Cell Association and Cytotoxic Efficiency

    Science.gov (United States)

    Jayanna, P.K.; Bedi, D; Gillespie, J.W.; DeInnocentes, P.; Wang, T; Torchilin, V.P; Bird, R.C.; Petrenko, V.A.

    2010-01-01

    Tumor-specific cytotoxicity of drugs can be enhanced by targeting them to tumor receptors using tumor-specific ligands. Phage display offers a high-throughput approach to screen for the targeting ligands. We have successfully isolated phage fusion peptides selective and specific for PC3 prostate cancer cells. Also, we have demonstrated a novel approach of targeting liposomes through tumor-specific phage fusion coat proteins, exploiting the intrinsic properties of the phage coat protein as an integral membrane protein. Here we describe the production of Rhodamine-labeled liposomes as well as doxorubicin-loaded long circulating liposomes targeted to PC3 prostate tumor cells via PC-specific phage peptides, as an extension of our previous studies. Targeting of labeled liposomes was demonstrated using fluorescence microscopy as well as flow cytometry. Targeting of doxorubicin-loaded liposomes enhanced their cytotoxic effect against PC3 cells in vitro indicating a possible therapeutic advantage. The simplicity of the approach for generating targeted liposomes coupled with the ability to rapidly obtain tumor-specific phage fusion proteins via phage display may contribute to a combinatorial system for the production of targeted liposomal therapeutics for advanced stages of prostate tumor. PMID:20138246

  14. VEGFR2 targeted antibody fused with MICA stimulates NKG2D mediated immunosurveillance and exhibits potent anti-tumor activity against breast cancer.

    Science.gov (United States)

    Xie, Wei; Liu, Fang; Wang, Youfu; Ren, Xueyan; Wang, Tong; Chen, Zhiguo; Tang, Mingying; Sun, Fumou; Li, Zhaoting; Wang, Min; Zhang, Juan

    2016-03-29

    Binding of MHC class I-related chain molecules A and B (MICA/B) to the natural killer (NK) cell receptor NK group 2, member D (NKG2D) is thought critical for activating NK-mediated immunosurveillance. Angiogenesis is important for tumor growth and interfering with angiogenesis using the fully human IgG1 anti-VEGFR2 (vascular endothelial growth factor receptor 2) antibody (mAb04) can be effective in treating malignancy. In an effort to make mAb04 more effective we have generated a novel antibody fusion protein (mAb04-MICA) consisting of mAb04 and MICA. We found that mAb04-MICA maintained the anti-angiogenic and antineoplastic activities of mAb04, and also enhanced immunosurveillance activated by the NKG2D pathway. Moreover, in human breast tumor-bearing nude mice, mAb04-MICA demonstrated superior anti-tumor efficacy compared to combination therapy of mAb04 + Docetaxel or Avastin + Docetaxel, highlighting the immunostimulatory effect of MICA. In conclusion, mAb04-MICA provided new inspiration for anti-tumor treatment and had prospects for clinical application.

  15. 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.

  16. 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.

  17. Both p53-PUMA/NOXA-Bax-mitochondrion and p53-p21cip1 pathways are involved in the CDglyTK-mediated tumor cell suppression

    International Nuclear Information System (INIS)

    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.

  18. Escape from p53-mediated tumor surveillance in neuroblastoma: switching off the p14(ARF)-MDM2-p53 axis.

    Science.gov (United States)

    Van Maerken, T; Vandesompele, J; Rihani, A; De Paepe, A; Speleman, F

    2009-12-01

    A primary failsafe program against unrestrained proliferation and oncogenesis is provided by the p53 tumor suppressor protein, inactivation of which is considered as a hallmark of cancer. Intriguingly, mutations of the TP53 gene are rarely encountered in neuroblastoma tumors, suggesting that alternative p53-inactivating lesions account for escape from p53 control in this childhood malignancy. Several recent studies have shed light on the mechanisms by which neuroblastoma cells circumvent the p53-driven antitumor barrier. We review here these mechanisms for evasion of p53-mediated growth control and conclude that deregulation of the p14(ARF)-MDM2-p53 axis seems to be the principal mode of p53 inactivation in neuroblastoma, opening new perspectives for targeted therapeutic intervention. PMID:19779493

  19. 腺苷A2a受体介导利血平引起的行为性抑郁%ADENOSINE A2A RECEPTOR MEDIATES RESERPINE-INDUCED DEPRESSION IN RATS

    Institute of Scientific and Technical Information of China (English)

    黄庆军; 郝新玲; ThomasRMinor

    2003-01-01

    Intraperitoneal injection of reserpine (4, 6 or 8 mg/kg) increased floating time in the Porsolt swim test in a dose-and time-dependent manner in rats. Although such behavioral depression usually is attributed to drug-induced depletion of brain monoamines, the outcome might be more directly related to brain adenosine signaling associated neuronal overactivation or brain cytokine induction following excitotoxic tissue damage. We addressed these possibilities by pretreating rats with caffeine (7 mg/kg), a high affinity adenosine receptor antagonist, prior to reserpine treatment (6 mg/kg). Caffeine partially reversed the ensuing behavioral depression as measured in the Prosolt swim test conducted 1, 24 and 72 hours after reserpine treatment. Further investigation has also been done to determine the subtype of adenosine receptor, which should mediate reserpine's effect. The results showed that adenosine A2 receptor antagonist (DMPX) and A2a antagonist (CSC) reversed the reserpine-induced behavioral depression dose-dependently. These results suggest that adenosine mediates reserpine-induced depression via adenosine A2a receptor and provide evidence that adenosine plays a crucial role in mediating behavioral depression, which will benefit in understanding the mechanism of depression and finding new drug for anti-depressant treatment.%研究腺苷在利血平引起的大鼠行为性抑郁中的作用.应用Porsolt游泳试验,观察注射利血平引起的大鼠行为性抑郁,通过腹腔注射非特异性腺苷受体阻断剂咖啡因和特异性A1和A2腺苷受体阻断剂,确定腺苷在利血平诱导的大鼠行为性抑郁中的作用以及介导这种作用的受体.结果发现:腹腔注射利血平(4、6和8 mg/kg)可导致大鼠在游泳试验中漂浮时间明显延长,咖啡因和A2a腺苷受体阻断剂能明显缩短利血平导致的漂浮时间的延长.结论:腺苷通过A2a受体介导利血平引起的大鼠的行为性抑郁.

  20. 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.

  1. Carnosine inhibits carbonic anhydrase IX-mediated extracellular acidosis and suppresses growth of HeLa tumor xenografts

    OpenAIRE

    Ditte, Zuzana; Ditte, Peter; Labudova, Martina; Simko, Veronika; Iuliano, Filippo; Zatovicova, Miriam; Csaderova, Lucia; Pastorekova, Silvia; Pastorek, Jaromir

    2014-01-01

    Background Carbonic anhydrase IX (CA IX) is a transmembrane enzyme that is present in many types of solid tumors. Expression of CA IX is driven predominantly by the hypoxia-inducible factor (HIF) pathway and helps to maintain intracellular pH homeostasis under hypoxic conditions, resulting in acidification of the tumor microenvironment. Carnosine (β-alanyl-L-histidine) is an anti-tumorigenic agent that inhibits the proliferation of cancer cells. In this study, we investigated the role of CA I...

  2. 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.

  3. 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.

  4. 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.

  5. Knockdown of platinum-induced growth differentiation factor 15 abrogates p27-mediated tumor growth delay in the chemoresistant ovarian cancer model A2780cis

    International Nuclear Information System (INIS)

    Molecular mechanisms underlying the development of resistance to platinum-based treatment in patients with ovarian cancer remain poorly understood. This is mainly due to the lack of appropriate in vivo models allowing the identification of resistance-related factors. In this study, we used human whole-genome microarrays and linear model analysis to identify potential resistance-related genes by comparing the expression profiles of the parental human ovarian cancer model A2780 and its platinum-resistant variant A2780cis before and after carboplatin treatment in vivo. Growth differentiation factor 15 (GDF15) was identified as one of five potential resistance-related genes in the A2780cis tumor model. Although A2780-bearing mice showed a strong carboplatin-induced increase of GDF15 plasma levels, the basal higher GDF15 plasma levels of A2780cis-bearing mice showed no further increase after short-term or long-term carboplatin treatment. This correlated with a decreased DNA damage response, enhanced AKT survival signaling and abrogated cell cycle arrest in the carboplatin-treated A2780cis tumors. Furthermore, knockdown of GDF15 in A2780cis cells did not alter cell proliferation but enhanced cell migration and colony size in vitro. Interestingly, in vivo knockdown of GDF15 in the A2780cis model led to a basal-enhanced tumor growth, but increased sensitivity to carboplatin treatment as compared to the control-transduced A2780cis tumors. This was associated with larger necrotic areas, a lobular tumor structure and increased p53 and p16 expression of the carboplatin-treated shGDF15-A2780cis tumors. Furthermore, shRNA-mediated GDF15 knockdown abrogated p27 expression as compared to control-transduced A2780cis tumors. In conclusion, these data show that GDF15 may contribute to carboplatin resistance by suppressing tumor growth through p27. These data show that GDF15 might serve as a novel treatment target in women with platinum-resistant ovarian cancer

  6. 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

  7. 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

  8. 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

    the possible positive or negative impact of these drugs on all known mechanisms of action of both type I and type II anti-CD20 antibodies. Pretreatment with ibrutinib for 1 hour did not increase direct cell death of cell lines or chronic lymphocytic leukemia samples mediated by anti-CD20 antibodies. Pre......-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...

  9. 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.

  10. Constitutive NF-κB activation and tumor-growth promotion by Romo1-mediated reactive oxygen species production

    International Nuclear Information System (INIS)

    Highlights: • Romo1 expression is required for constitutive nuclear DNA-binding activity of NF-κB. • Romo1 depletion suppresses tumor growth in vivo. • Romo1 presents a potential therapeutic target for diseases. - Abstract: Deregulation of nuclear factor-κB (NF-κB) and related pathways contribute to tumor cell proliferation and invasion. Mechanisms for constitutive NF-κB activation are not fully explained; however, the underlying defects appear to generate and maintain pro-oxidative conditions. In hepatocellular carcinoma (HCC) tissues, up-regulation of reactive oxygen species modulator 1 (Romo1) correlates positively with tumor size. In the present study, we showed that Romo1 expression is required to maintain constitutive nuclear DNA-binding activity of NF-κB and transcriptional activity through constitutive IκBα phosphorylation. Overexpression of Romo1 promoted p65 nuclear translocation and DNA-binding activity. We also show that Romo1 depletion suppressed anchorage-independent colony formation by HCC cells and suppressed tumor growth in vivo. Based on these findings, Romo1 may be a principal regulatory factor in the maintenance of constitutive NF-κB activation in tumor cells. In the interest of anti-proliferative treatments for cancer, Romo1 may also present a productive target for drug development

  11. Involvement of BH4 domain of bcl-2 in the regulation of HIF-1-mediated VEGF expression in hypoxic tumor cells.

    Science.gov (United States)

    Trisciuoglio, D; Gabellini, C; Desideri, M; Ragazzoni, Y; De Luca, T; Ziparo, E; Del Bufalo, D

    2011-06-01

    In addition to act as an antiapoptotic protein, B-cell lymphoma (bcl)-2 can also promote tumor angiogenesis. In this context, we have previously demonstrated that under hypoxia bcl-2 promotes hypoxia-inducible factor-1 (HIF-1)-mediated vascular endothelial growth factor (VEGF) expression in melanoma and breast carcinoma. Here, we report on the role of the BH4 domain in bcl-2 functions, by showing that removal of or mutations at the BH4 domain abrogate the ability of bcl-2 to induce VEGF protein expression and transcriptional activity under hypoxia in human melanoma cells. We have also extended this observation to other human tumor histotypes, such as colon, ovarian and lung carcinomas. The involvement of BH4 on HIF-1α protein expression, stability, ubiquitination and HIF-1 transcriptional activity was also demonstrated in melanoma experimental model. Moreover, we validated the role of the BH4 domain of bcl-2 in the regulation of HIF-1/VEGF axis, demonstrating that BH4 peptide is sufficient to increase HIF-1α protein half-life impairing HIF-1α protein ubiquitination, and to enhance VEGF secretion in melanoma cells exposed to hypoxia. Finally, we found that the mechanism by which bcl-2 regulates HIF-1-mediated VEGF expression does not require BH1 and BH2 domains, and it is independent of antiapoptotic and prosurvival function of bcl-2. PMID:21233846

  12. Increased desensitization of dopamine D₂ receptor-mediated response in the ventral tegmental area in the absence of adenosine A(2A) receptors.

    Science.gov (United States)

    Al-Hasani, R; Foster, J D; Metaxas, A; Ledent, C; Hourani, S M O; Kitchen, I; Chen, Y

    2011-09-01

    G-protein coupled receptors interact to provide additional regulatory mechanisms for neurotransmitter signaling. Adenosine A(2A) receptors are expressed at a high density in striatal neurons, where they closely interact with dopamine D₂ receptors and modulate effects of dopamine and responses to psychostimulants. A(2A) receptors are expressed at much lower densities in other forebrain neurons but play a more prominent yet opposing role to striatal receptors in response to psychostimulants in mice. It is, therefore, possible that A(2A) receptors expressed at low levels elsewhere in the brain may also regulate neurotransmitter systems and modulate neuronal functions. Dopamine D₂ receptors play an important role in autoinhibition of neuronal firing in dopamine neurons of the ventral tegmental area (VTA) and dopamine release in other brain areas. Here, we examined the effect of A(2A) receptor deletion on D₂ receptor-mediated inhibition of neuronal firing in dopamine neurons in the VTA. Spontaneous activity of dopamine neurons was recorded in midbrain slices, and concentration-dependent effects of the dopamine D₂ receptor agonist, quinpirole, was compared between wild-type and A(2A) knockout mice. The potency of quinpirole applied in single concentrations and the expression of D₂ receptors were not altered in the VTA of the knockout mice. However, quinpirole applied in stepwise escalating concentrations caused significantly reduced maximal inhibition in A(2A) knockout mice, indicating an enhanced agonist-induced desensitization of D₂ receptors in the absence of A(2A) receptors. The A(2A) receptor agonist, CGS21680, did not exert any effect on dopamine neuron firing or response to quinpirole, revealing a novel non-pharmacological interaction between adenosine A(2A) receptors and dopaminergic neurotransmission in midbrain dopamine neurons. Altered D₂ receptor desensitization may result in changes in dopamine neuron firing rate and pattern and dopamine

  13. Oestrogen compromises the facilitatory effect of chronic nicotine on adenosine A2B receptor-K(+) channel-mediated renal vasodilation.

    Science.gov (United States)

    El-Mas, Mahmoud M; El-Gowilly, Sahar M; Elsalakawy, Lamia K; El-Gowelli, Hanan M

    2014-08-01

    We have shown previously that the renal vasodilatory action of the adenosine analogue 5'-N-ethylcarboxamidoadenosine (NECA) in female rats is mediated via preferential activation of adenosine A2B receptor (A2B R)-K(+) channel signalling. In the present study, we tested the hypothesis that the renal vasodilatory effect of NECA and its A2B R/K(+) channel specificities are altered by chronic nicotine administration. The oestrogenic modulation of the nicotine-NECA renovascular interaction was also evaluated by determining the effect of ovariectomy (OVX) and oestrogen replacement (OVXE2) on the evoked responses. In isolated phenylephrine-preconstricted perfused kidneys obtained from sham-operated rats, vasodilation in response to cumulative bolus injections of NECA (1.6-50 nmol) or papaverine (1-243 nmol) were not affected by nicotine (1-8 mg/kg per day, i.p., 2 weeks). However, vasodilator responses to NECA, but not papaverine, were reduced in kidneys of OVX rats and restored to near-sham values after E2 replacement. Further, nicotine increased NECA-induced vasodilation in perfused kidneys from OVX rats, but failed to do so in OVXE2 preparations. The enhanced NECA responsiveness in nicotine-treated OVX preparations was abolished after infusion (into isolated kidneys) of 10 μmol/L alloxazine (A2B R antagonist) or BaCl2 plus glibenclamide (blockers of inward rectifier and ATP-sensitive K(+) channels, respectively). Vasodilator responses to 0.05-1.6 μmol minoxidil (a K(+) channel opener) were increased by nicotine in OVX, but not OVXE2, preparations and this increase was abolished after infusion of BaCl2  + glibenclamide. Together, the data suggest that chronic nicotine enhances A2B R/K(+) channel-mediated renal vasodilation in oestrogen-depleted rats. PMID:24827542

  14. The characterization of an intestine-like genomic signature maintained during Barrett’s-associated adenocarcinogenesis reveals an NR5A2-mediated promotion of cancer cell survival

    Science.gov (United States)

    Duggan, Shane P.; Behan, Fiona M.; Kirca, Murat; Zaheer, Abdul; McGarrigle, Sarah A.; Reynolds, John V.; Vaz, Gisela M. F.; Senge, Mathias O.; Kelleher, Dermot

    2016-09-01

    Barrett’s oesophagus (BO), an intestinal-type metaplasia (IM), typically arising in conjunction with gastro-oesophageal reflux disease, is a prominent risk factor for the development of oesophageal adenocarcinoma (OAC). The molecular similarities between IM and normal intestinal tissues are ill-defined. Consequently, the contribution of intestine-enriched factors expressed within BO to oncogenesis is unclear. Herein, using transcriptomics we define the intestine-enriched genes expressed in meta-profiles of BO and OAC. Interestingly, 77% of the genes differentially expressed in a meta-profile of BO were similarly expressed in intestinal tissues. Furthermore, 85% of this intestine-like signature was maintained upon transition to OAC. Gene networking analysis of transcription factors within this signature revealed a network centred upon NR5A2, GATA6 and FOXA2, whose over-expression was determined in a cohort of BO and OAC patients. Simulated acid reflux was observed to induce the expression of both NR5A2 and GATA6. Using siRNA-mediated silencing and an NR5A2 antagonist we demonstrate that NR5A2-mediated cancer cell survival is facilitated through augmentation of GATA6 and anti-apoptotic factor BCL-XL levels. Abrogation of NR5A2-GATA6 expression in conjunction with BCL-XL co-silencing resulted in synergistically increased sensitivity to chemotherapeutics and photo-dynamic therapeutics. These findings characterize the intestine-like signature associated with IM which may have important consequences to adenocarcinogenesis.

  15. 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. PMID:25878495

  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

    International Nuclear Information System (INIS)

    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. We examined the effects of loss of SRC-1 on MMTV-neu mediated mammary tumorigenesis. 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. These results indicate that histone acetyltransferases play key roles in mammary tumorigenesis and response to anti-proliferative therapies

  17. Somatostatin Receptor-Mediated Tumor-Targeting Nanocarriers Based on Octreotide-PEG Conjugated Nanographene Oxide for Combined Chemo and Photothermal Therapy.

    Science.gov (United States)

    Zhang, Xuyuan; Yang, Chongyin; Zhou, Jianping; Huo, Meirong

    2016-07-01

    Nano-sized in vivo active targeting drug delivery systems have been developed to a high anti-tumor efficacy strategy against certain cancer-cells-specific. Graphene based nanocarriers with unique physical and chemical properties have shown significant potentials in this aspect. Here, octreotide (OCT), an efficient biotarget molecule, is conjugated to PEGylated nanographene oxide (NGO) drug carriers for the first time. The obtained NGO-PEG-OCT complex shows low toxicity and excellent stability in vivo and is able to achieve somatostatin receptor-mediated tumor-specific targeting delivery. Owing to the high loading efficiency and accurate targeting delivery of anti-cancer drug doxorubicin (DOX), our DOX loaded NGO-PEG-OCT complex offers a remarkably improved cancer-cell-specific cellular uptake, chemo-cytotoxicity, and decreased systemic toxicity compared to free DOX or NGO-PEG. More importantly, due to its strong near-infrared absorption, the NGO-PEG-OCT complex further enhances efficient photothermal ablation of tumors, delivering combined chemo and photothermal therapeutic effect against cancer cells. PMID:27244649

  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. Cytosolic phospholipase A2 activation correlates with HER2 overexpression and mediates estrogen-dependent breast cancer cell growth.

    OpenAIRE

    Caiazza, Francesco; Harvey, Brian J; Thomas, Warren

    2010-01-01

    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 rapid...

  20. 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

  1. 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

    .15) on a fast growing subpopulation (E1.95) was demonstrated only when the cells had contact during solid tumor growth. The effect was dependent on the relative proportion of the suppressing cell line. An identical effect was exerted by radiation killed inhibitor cells. The inhibition was only transient....... If the tumor cell lines were grown intraperitoneally as ascites tumors without cellular contact, no interaction was found using flow cytometric DNA analysis to determine alterations in the relative proportions of the cell lines. Ascites from the inhibitor cell line E1.15 had no inhibitory effect on E1.95. Pre......-immunization with radiation killed E1.15 cells or simultaneous growth of E1.15 in the opposite flank did not affect the growth of E1.95 significantly. A mononuclear cell infiltrate was found to surround the subcutaneously growing E1.15 tumors in immune competent N/D mice. This was not the case in T-lymphocyte deficient...

  2. Oncolytic adenovirus-mediated transfer of the antisense chk2 selectively inhibits tumor growth in vitro and in vivo.

    Science.gov (United States)

    Chen, G; Zhou, J; Gao, Q; Huang, X; Li, K; Zhuang, L; Huang, M; Xu, G; Wang, S; Lu, Y; Ma, D

    2006-10-01

    Screening and identifying molecules target to checkpoint pathways has fostered the development of checkpoint-based anticancer strategies. Among these targets, inhibition of chk2 may induce cell death for tumors whose growth depends on enhanced chk2 activity. However, improvement of the potency and specificity of such therapeutics remains a major challenge. To resolve this problem, we constructed M3, a novel recombinant adenovirus with a 27-bp deletion in E1A CR2 region by which to realize tumor-specific replication, and an 829-bp of antisense chk2 fragment inserted into the E3 coding region. In this design, M3 exploited the native adenovirus E3 promoters to express antisense chk2 cDNA in a viral replication-dependent fashion, and preferentially silenced the chk2 gene in tumor cells. In vitro and in vivo assays confirmed that downregulated chk2 expression induced by M3 infection was tumor-specific and virus replication-dependent. Furthermore, systemic administration of M3 combined with a low dose of cisplatin cured 75% (9/12) of orthotopic hepatic carcinoma mouse models that were otherwise resistant to cisplatin. Our results indicated that the upcoming development in this field would improve the antitumor efficacy and maximize the synergistic effect of oncolytic viruses administered with traditional chemotherapy or radiotherapy. PMID:16741520

  3. 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

  4. 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...

  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. 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.

  7. 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.

  8. The strong in vivo anti-tumor effect of the UIC2 monoclonal antibody is the combined result of Pgp inhibition and antibody dependent cell-mediated cytotoxicity.

    Directory of Open Access Journals (Sweden)

    Gábor Szalóki

    Full Text Available P-glycoprotein (Pgp extrudes a large variety of chemotherapeutic drugs from the cells, causing multidrug resistance (MDR. The UIC2 monoclonal antibody recognizes human Pgp and inhibits its drug transport activity. However, this inhibition is partial, since UIC2 binds only to 10-40% of cell surface Pgps, while the rest becomes accessible to this antibody only in the presence of certain substrates or modulators (e.g. cyclosporine A (CsA. The combined addition of UIC2 and 10 times lower concentrations of CsA than what is necessary for Pgp inhibition when the modulator is applied alone, decreased the EC50 of doxorubicin (DOX in KB-V1 (Pgp+ cells in vitro almost to the level of KB-3-1 (Pgp- cells. At the same time, UIC2 alone did not affect the EC50 value of DOX significantly. In xenotransplanted severe combined immunodeficient (SCID mice co-treated with DOX, UIC2 and CsA, the average weight of Pgp+ tumors was only ∼10% of the untreated control and in 52% of these animals we could not detect tumors at all, while DOX treatment alone did not decrease the weight of Pgp+ tumors. These data were confirmed by visualizing the tumors in vivo by positron emission tomography (PET based on their increased 18FDG accumulation. Unexpectedly, UIC2+DOX treatment also decreased the size of tumors compared to the DOX only treated animals, as opposed to the results of our in vitro cytotoxicity assays, suggesting that immunological factors are also involved in the antitumor effect of in vivo UIC2 treatment. Since UIC2 binding itself did not affect the viability of Pgp expressing cells, but it triggered in vitro cell killing by peripheral blood mononuclear cells (PBMCs, it is concluded that the impressive in vivo anti-tumor effect of the DOX-UIC2-CsA treatment is the combined result of Pgp inhibition and antibody dependent cell-mediated cytotoxicity (ADCC.

  9. The strong in vivo anti-tumor effect of the UIC2 monoclonal antibody is the combined result of Pgp inhibition and antibody dependent cell-mediated cytotoxicity.

    Science.gov (United States)

    Szalóki, Gábor; Krasznai, Zoárd T; Tóth, Ágnes; Vízkeleti, Laura; Szöllősi, Attila G; Trencsényi, György; Lajtos, Imre; Juhász, István; Krasznai, Zoltán; Márián, Teréz; Balázs, Margit; Szabó, Gábor; Goda, Katalin

    2014-01-01

    P-glycoprotein (Pgp) extrudes a large variety of chemotherapeutic drugs from the cells, causing multidrug resistance (MDR). The UIC2 monoclonal antibody recognizes human Pgp and inhibits its drug transport activity. However, this inhibition is partial, since UIC2 binds only to 10-40% of cell surface Pgps, while the rest becomes accessible to this antibody only in the presence of certain substrates or modulators (e.g. cyclosporine A (CsA)). The combined addition of UIC2 and 10 times lower concentrations of CsA than what is necessary for Pgp inhibition when the modulator is applied alone, decreased the EC50 of doxorubicin (DOX) in KB-V1 (Pgp+) cells in vitro almost to the level of KB-3-1 (Pgp-) cells. At the same time, UIC2 alone did not affect the EC50 value of DOX significantly. In xenotransplanted severe combined immunodeficient (SCID) mice co-treated with DOX, UIC2 and CsA, the average weight of Pgp+ tumors was only ∼10% of the untreated control and in 52% of these animals we could not detect tumors at all, while DOX treatment alone did not decrease the weight of Pgp+ tumors. These data were confirmed by visualizing the tumors in vivo by positron emission tomography (PET) based on their increased 18FDG accumulation. Unexpectedly, UIC2+DOX treatment also decreased the size of tumors compared to the DOX only treated animals, as opposed to the results of our in vitro cytotoxicity assays, suggesting that immunological factors are also involved in the antitumor effect of in vivo UIC2 treatment. Since UIC2 binding itself did not affect the viability of Pgp expressing cells, but it triggered in vitro cell killing by peripheral blood mononuclear cells (PBMCs), it is concluded that the impressive in vivo anti-tumor effect of the DOX-UIC2-CsA treatment is the combined result of Pgp inhibition and antibody dependent cell-mediated cytotoxicity (ADCC). PMID:25238617

  10. RNAi-mediated silencing of HLA A2 suppressed acute rejection against human fibroblast xenografts in the striatum of 6-OHDA lesioned rats.

    Science.gov (United States)

    Liang, Caixia; Xu, Yunzhi; Zheng, Deyu; Sun, Xiaohong; Xu, Qunyuan; Duan, Deyi

    2016-08-15

    Major histocompatibility complex class l (MHC I) molecules play a role in determining whether transplanted cells will be accepted or rejected, and masking of MHC I on donor cells has been found useful for immunoprotection of neural xenografts. In the present study, primary human embryonic lung fibroblasts (HELF), HELF treated with lentivirus-mediated small interfering RNAs (siRNAs) targeting human leukocyte antigen A2 (HLA A2, MHC I in humans) (siHELF), and rat embryonic lung fibroblasts (RELF) were stereotaxically grafted into the striatum of 6-hydroxydopamine lesioned rats to explore whether knockdown of HLA A2 could reduce host immune responses against xenografts. Before lentiviral infection, the cells were transduced with retroviruses harboring tyrosine hydroxylase cDNA. Knockdown of HLA A2 protein was examined by Western blotting. The immune responses (the number of CD4 and CD8 T-cells in the brain and peripheral blood), glial reaction, and survival of human fibroblasts were quantitatively evaluated by flow cytometry and immunohistochemistry at 4d, 2w, and 6w post-graft. Animal behaviors were assessed by counting apomorphine-induced rotations pre- and post-grafts. It was shown that a lower level of HLA A2 was observed in siHELF grafts than in HELF grafts, and knockdown of HLA A2 decreased rat immune responses, as indicated by less remarkable increases in the number of CD8 and CD4 T-cells in the brain and the ratio of CD4:CD8 T-cells in the peripheral blood in rats grafted with siHELF. Rats grafted with siHELF exhibited a significant improvement in motor asymmetry post-transplantation and a better survival of human fibroblasts at 2w. The increasing number of activated microglia and the decreasing number of astrocytes were found in three groups of rats post-implantation. These data suggested that RNAi-mediated knockdown of HLA A2 could suppress acute rejection against xenogeneic human cell transplants in the rat brain. PMID:27397073

  11. 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.

  12. 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

    2016-12-01

    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. PMID:26932761

  13. Regression of established pulmonary metastases and subcutaneous tumor mediated by the systemic administration of high-dose recombinant interleukin 2

    OpenAIRE

    1985-01-01

    Incubation of resting lymphoid cells with recombinant interleukin 2 (IL- 2) in vitro leads to the generation of lymphokine activated killer (LAK) cells capable of lysing fresh tumor cell suspensions in short- term chromium-release assays. Our previous studies (7) have demonstrated that the injection of LAK cells plus low doses of recombinant IL-2 were capable of inhibiting the growth of pulmonary metastases. We have now explored the ability of high doses of recombinant IL-2, administered syst...

  14. NSK-01105, a Novel Sorafenib Derivative, Inhibits Human Prostate Tumor Growth via Suppression of VEGFR2/EGFR-Mediated Angiogenesis

    Science.gov (United States)

    Yu, Pengfei; Ye, Liang; Wang, Hongbo; Du, Guangying; Zhang, Jianzhao; Zuo, Yanhua; Zhang, Jinghai; Tian, Jingwei

    2014-01-01

    The purpose of this study is to investigate the anti-angiogenic activities of NSK-01105, a novel sorafenib derivative, in in vitro, ex vivo and in vivo models, and explore the potential mechanisms. NSK-01105 significantly inhibited vascular endothelial growth factor (VEGF)-induced migration and tube formation of human umbilical vein endothelial cells at non-cytotoxic concentrations as shown by wound-healing, transwell migration and endothelial cell tube formation assays, respectively. Cell viability and invasion of LNCaP and PC-3 cells were significantly inhibited by cytotoxicity assay and matrigel invasion assay. Furthermore, NSK-01105 also inhibited ex vivo angiogenesis in matrigel plug assay. Western blot analysis showed that NSK-01105 down-regulated VEGF-induced phosphorylation of VEGF receptor 2 (VEGFR2) and the activation of epidermal growth factor receptor (EGFR). Tumor volumes were significantly reduced by NSK-01105 at 60 mg/kg/day in both xenograft models. Immunohistochemical staining demonstrated a close association between inhibition of tumor growth and neovascularization. Collectively, our results suggest a role of NSK-01105 in treatment for human prostate tumors, and one of the potential mechanisms may be attributed to anti-angiogenic activities. PMID:25551444

  15. 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.

  16. 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. PMID:16023100

  17. 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

  18. 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.

  19. 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.

  20. Granulocyte-Macrophage Colony-Stimulating Factor- and Tumor Necrosis Factor Alpha-Mediated Matrix Metalloproteinase Production by Human Osteoblasts and Monocytes after Infection with Brucella abortus ▿

    Science.gov (United States)

    Scian, Romina; Barrionuevo, Paula; Giambartolomei, Guillermo H.; Fossati, Carlos A.; Baldi, Pablo C.; Delpino, M. Victoria

    2011-01-01

    Osteoarticular complications are common in human brucellosis, but the pathogenic mechanisms involved are largely unknown. Since matrix metalloproteinases (MMPs) are involved in joint and bone damage in inflammatory and infectious diseases, we investigated the production of MMPs by human osteoblasts and monocytes, either upon Brucella abortus infection or upon reciprocal stimulation with factors produced by each infected cell type. B. abortus infection of the normal human osteoblastic cell line hFOB 1.19 triggered a significant release of MMP-2, which was mediated in part by granulocyte-macrophage colony-stimulating factor (GM-CSF) acting on these same cells. Supernatants from infected osteoblasts exhibited increased levels of monocyte chemoattractant protein 1 and induced the migration of human monocytes (THP-1 cell line). Infection with B. abortus induced a high MMP-9 secretion in monocytes, which was also induced by heat-killed B. abortus and by the Omp19 lipoprotein from B. abortus. These effects were mediated by Toll-like receptor 2 and by the action of tumor necrosis factor alpha (TNF-α) produced by these same cells. Supernatants from B. abortus-infected monocytes induced MMP-2 secretion in uninfected osteoblasts, and this effect was mediated by TNF-α. Similarly, supernatants from infected osteoblasts induced MMP-9 secretion in uninfected monocytes. This effect was mediated by GM-CSF, which induced TNF-α production by monocytes, which in turn induced MMP-9 in these cells. These results suggest that MMPs could be potentially involved in the tissue damage observed in osteoarticular brucellosis. PMID:20956574

  1. Adenovirus-mediated interleukin-12 gene transfer combined with cytosine deaminase followed by 5-fluorocytosine treatment exerts potent antitumor activity in Renca tumor-bearing mice

    International Nuclear Information System (INIS)

    Therapeutic gene transfer affords a clinically feasible and safe approach to cancer treatment but a more effective modality is needed to improve clinical outcomes. Combined transfer of therapeutic genes with different modes of actions may be a means to this end. Interleukin-12 (IL-12), a heterodimeric immunoregulatory cytokine composed of covalently linked p35 and p40 subunits, has antitumor activity in animal models. The enzyme/prodrug strategy using cytosine deaminase (CD) and 5-fluorocytosine (5-FC) has been used for cancer gene therapy. We have evaluated the antitumor effect of combining IL-12 with CD gene transfer in mice bearing renal cell carcinoma (Renca) tumors. Adenoviral vectors were constructed encoding one or both subunits of murine IL-12 (Ad.p35, Ad.p40 and Ad.IL-12) or cytosine deaminase (Ad.CD). The functionality of the IL-12 or CD gene products expressed from these vectors was validated by splenic interferon (IFN)-γ production or viability assays in cultured cells. Ad.p35 plus Ad.p40, or Ad.IL-12, with or without Ad.CD, were administered (single-dose) intratumorally to Renca tumor-bearing mice. The animals injected with Ad.CD also received 5-FC intraperitoneally. The antitumor effects were then evaluated by measuring tumor regression, mean animal survival time, splenic natural killer (NK) cell activity and IFN-γ production. The inhibition of tumor growth in mice treated with Ad.p35 plus Ad.p40 and Ad.CD, followed by injection of 5-FC, was significantly greater than that in mice treated with Ad.CD/5-FC, a mixture of Ad.p35 plus Ad.p40, or Ad.GFP (control). The combined gene transfer increased splenic NK cell activity and IFN-γ production by splenocytes. Ad.CD/5-FC treatment significantly increased the antitumor effect of Ad.IL-12 in terms of tumor growth inhibition and mean animal survival time. The results suggest that adenovirus-mediated IL-12 gene transfer combined with Ad.CD followed by 5-FC treatment may be useful for treating cancers

  2. 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.

  3. 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

  4. 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

  5. Growth Suppression of Human Lung Cancer Cells and Implanted Tumors by Adenovirus-mediated Transfer of the PTEN Gene

    Institute of Scientific and Technical Information of China (English)

    陈志雄; 杨炯

    2010-01-01

    This study examined the effects of a recombinant adenovirus Ad-PTEN-EGFP on the proliferation of A549 cells,a human lung carcinoma cell line,in vitro and on the growth of the implanted tumors in the nude mice in vivo,explored the underlying mechanisms and evaluated the in vitro transfection efficiency of Ad-PTEN-EGFP into A549 cells.The expression of Ad-PTEN-EGFP in the A549 cells was determined.The proliferation and the apoptosis rates of the A549 cells with Ad-PTEN-EGFP transfection or not was detected by...

  6. Activation of the Retinoblastoma Tumor Suppressor Mediates Cell Cycle Inhibition and Cell Death in Specific Cervical Cancer Cell Lines

    OpenAIRE

    Bourgo, Ryan J.; Braden, Wesley A.; Wells, Susanne I.; Knudsen, Erik S.

    2009-01-01

    High-risk human papilloma virus (HPV) encodes two oncoproteins, E6 and E7, which are vital to viral replication and contribute to the development of cervical cancer. HPV16 E7 can target over 20 cellular proteins, but is best known for inactivating the retinoblastoma (RB) tumor suppressor. RB functions by restraining cells from entering S-phase of the cell cycle, thus preventing aberrant proliferation. While it is well established that HPV16 E7 facilitates the degradation of the RB protein, th...

  7. Striatal adenosine A2A receptor-mediated positron emission tomographic imaging in 6-hydroxydopamine-lesioned rats using [18F]-MRS5425

    International Nuclear Information System (INIS)

    Introduction: A2A receptors are expressed in the basal ganglia, specifically in striatopallidal GABAergic neurons in the striatum (caudate-putamen). This brain region undergoes degeneration of presynaptic dopamine projections and depletion of dopamine in Parkinson's disease. We developed an 18F-labeled A2A analog radiotracer ([18F]-MRS5425) for A2A receptor imaging using positron emission tomography (PET). We hypothesized that this tracer could image A2A receptor changes in the rat model for Parkinson's disease, which is created following unilateral injection of the monoaminergic toxin 6-hydroxydopamine (6-OHDA) into the substantia nigra. Methods: [18F]-MRS5425 was injected intravenously in anesthetized rats, and PET imaging data were collected. Image-derived percentage injected doses per gram (%ID/g) in regions of interest was measured in the striatum of normal rats and in rats unilaterally lesioned with 6-OHDA after intravenous administration of saline (baseline), D2 agonist quinpirole (1.0 mg/kg) or D2 antagonist raclopride (6.0 mg/kg). Results: Baseline %ID/g reached a maximum at 90 s and maintained plateau for 3.5 min, and then declined slowly thereafter. In 6-OHDA-lesioned rats, %ID/g was significantly higher in the lesioned side compared to the intact side, and the baseline total %ID/g (data from both hemispheres were combined) was significantly higher compared to quinpirole stimulation starting from 4.5 min until the end of acquisition at 30 min. Raclopride did not produce any change in uptake compared to baseline or between the hemispheres. Conclusion: Thus, increase of A2A receptor-mediated uptake of radioactive MRS5425 could be a superior molecular target for Parkinson's imaging.

  8. 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

    International Nuclear Information System (INIS)

    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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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

  15. RNAi-mediated knockdown of pituitary tumor-transforming gene-1 (PTTG1) suppresses the proliferation and invasive potential of PC3 human prostate cancer cells

    International Nuclear Information System (INIS)

    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

  16. 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.

  17. 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. PMID:27512904

  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. 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. PMID:27564996

  20. Tumor suppressor and oncogene actions of TGFβ1 occur early in skin carcinogenesis and are mediated by Smad3

    OpenAIRE

    Bae, Dong-Soon; Blazanin, Nicholas; Licata, Mathew; Lee, Jessica; Glick, Adam B.

    2009-01-01

    Interactions between TGFβ1 and ras signaling pathways play an important role in cancer development. Here we show that in primary mouse keratinocytes, v-rasHa does not block the early biochemical events of TGFβ1 signal transduction but does alter global TGFβ1 mediated gene expression in a gene specific manner. Expression of Smad3 dependent TGFβ1 early response genes and the TGFβ1 cytostatic gene expression response were not altered by v-rasHa consistent with an intact TGFβ1 growth arrest. Howe...

  1. CF102 an A3 adenosine receptor agonist mediates anti-tumor and anti-inflammatory effects in the liver.

    Science.gov (United States)

    Cohen, S; Stemmer, S M; Zozulya, G; Ochaion, A; Patoka, R; Barer, F; Bar-Yehuda, S; Rath-Wolfson, L; Jacobson, K A; Fishman, P

    2011-09-01

    The Gi protein-associated A(3) adenosine receptor (A(3) AR) is a member of the adenosine receptor family. Selective agonists at the A(3) AR, such as CF101 and CF102 were found to induce anti-inflammatory and anti-cancer effects. In this study, we examined the differential effect of CF102 in pathological conditions of the liver. The anti-inflammatory protective effect of CF101 was tested in a model of liver inflammation induced by Concanavalin A (Con. A) and the anti-cancer effect of CF102 was examined in vitro and in a xenograft animal model utilizing Hep-3B hepatocellular carcinoma (HCC) cells. The mechanism of action was explored by following the expression levels of key signaling proteins in the inflamed and tumor liver tissues, utilizing Western blot (WB) analysis. In the liver inflammation model, CF102 (100 µg/kg) markedly reduced the secretion of serum glutamic oxaloacetic transaminase and serum glutamic pyruvic transaminase in comparison to the vehicle-treated group. Mechanistically, CF102 treatment decreased the expression level of phosphorylated glycogen synthase kinase-3β, NF-κB, and TNF-α and prevented apoptosis in the liver. This was demonstrated by decreased expression levels of Fas receptor (FasR) and of the pro-apoptotic proteins Bax and Bad in liver tissues. In addition, CF102-induced apoptosis of Hep-3B cells both in vitro and in vivo via de-regulation of the PI3K-NF-κB signaling pathway, resulting in up-regulation of pro-apoptotic proteins. Taken together, CF102 acts as a protective agent in liver inflammation and inhibits HCC tumor growth. These results suggest that CF102 through its differential effect is a potential drug candidate to treat various pathological liver conditions. PMID:21660967

  2. KLF4 regulates adult lung tumor-initiating cells and represses K-Ras-mediated lung cancer.

    Science.gov (United States)

    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.

  3. Analyses of CD20 Monoclonal Antibody–Mediated Tumor Cell Killing Mechanisms: Rational Design of Dosing Strategies

    Science.gov (United States)

    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

  4. CD133/Src axis mediates tumor initiating property and epithelial-mesenchymal transition of head and neck cancer.

    Directory of Open Access Journals (Sweden)

    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.

  5. The NF2 tumor suppressor gene product, merlin, mediates contact inhibition of growth through interactions with CD44

    Energy Technology Data Exchange (ETDEWEB)

    Morrison, H.L.

    2002-03-01

    The neurofibromatosis-2 (NF2) gene encodes merlin, an ezrin-radixin-moesin-(ERM)-related protein, that functions as a tumor suppressor. I found that merlin plays a critical role in the establishment and maintenance of contact inhibition of growth. At high cell density, merlin is activated and blocks profileration with corresponding changes in cell cycle parameters. Merlin interfered with growth factor receptor or Ras-dependent signal transduction of MAP kinase and the step of interference was located downstream of Ras and Raf and upstream of MEK. Merlins growth inhibiting function depended on interaction with a specific domain of the cytoplasmic tail of CD44. In addition merlin activity and phosphorylation status depended on the extracellular ligand associated with the N-terminus of CD44. At high cell densities, in the presence of the extracellular ligand HA, merlin was dephosphorylated and bound directly to a basic amino acid motif in the cytoplasmic tail of CD44. Ezrin and moesin, which are also known to bind to the same basic amino acid motif in CD44 were absent within this growth inhibitory complex. Alternatively in logarithmically growing cells, merlin was inactive, phosphorylated and in a complex with ezrin and moesin. This growth permissive complex was also associated with the cytoplasmic tail of CD44. My data provide not only significant clues about how merlin functions as a tumor suppressor but revealed the existence of a novel molecular switch that, under the influence of ligands in the microenvironment, controls a cell decision to proliferate or growth arrest. (orig.)

  6. Expression proteomics of UPF1 knockdown in HeLa cells reveals autoregulation of hnRNP A2/B1 mediated by alternative splicing resulting in nonsense-mediated mRNA decay

    Directory of Open Access Journals (Sweden)

    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.

  7. Nonislet Cell Tumor Hypoglycemia

    OpenAIRE

    Johnson Thomas; Salini C. Kumar

    2013-01-01

    Nonislet cell tumor hypoglycemia (NICTH) is a rare cause of hypoglycemia. It is characterized by increased glucose utilization by tissues mediated by a tumor resulting in hypoglycemia. NICTH is usually seen in large mesenchymal tumors including tumors involving the GI tract. Here we will discuss a case, its pathophysiology, and recent advances in the management of NICTH. Our patient was diagnosed with poorly differentiated squamous cell carcinoma of esophagus. He continued to be hypoglycemic ...

  8. The mediation of the central histaminergic system in the pressor effect of intracerebroventricularly injected melittin, a phospholipase A2 activator, in normotensive rats.

    Science.gov (United States)

    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.

  9. A widespread sequence-specific mRNA decay pathway mediated by hnRNPs A1 and A2/B1.

    Science.gov (United States)

    Geissler, Rene; Simkin, Alfred; Floss, Doreen; Patel, Ravi; Fogarty, Elizabeth A; Scheller, Jürgen; Grimson, Andrew

    2016-05-01

    3'-untranslated regions (UTRs) specify post-transcriptional fates of mammalian messenger RNAs (mRNAs), yet knowledge of the underlying sequences and mechanisms is largely incomplete. Here, we identify two related novel 3' UTR motifs in mammals that specify transcript degradation. These motifs are interchangeable and active only within 3' UTRs, where they are often preferentially conserved; furthermore, they are found in hundreds of transcripts, many encoding regulatory proteins. We found that degradation occurs via mRNA deadenylation, mediated by the CCR4-NOT complex. We purified trans factors that recognize the motifs and identified heterogeneous nuclear ribonucleoproteins (hnRNPs) A1 and A2/B1, which are required for transcript degradation, acting in a previously unknown manner. We used RNA sequencing (RNA-seq) to confirm hnRNP A1 and A2/B1 motif-dependent roles genome-wide, profiling cells depleted of these factors singly and in combination. Interestingly, the motifs are most active within the distal portion of 3' UTRs, suggesting that their role in gene regulation can be modulated by alternative processing, resulting in shorter 3' UTRs.

  10. Highly sensitive proximity mediated immunoassay reveals HER2 status conversion in the circulating tumor cells of metastatic breast cancer patients

    Directory of Open Access Journals (Sweden)

    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

  11. Impaired Th1 immunity in ovarian cancer patients is mediated by TNFR2+ Tregs within the tumor microenvironment.

    Science.gov (United States)

    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.

  12. Development of a synthetic receptor protein for sensing inflammatory mediators interferon-γ and tumor necrosis factor-α.

    Science.gov (United States)

    Aurand, T Christopher; March, John C

    2016-03-01

    Intestinal inflammation has been implicated in a number of diseases, including diabetes, Crohn's disease, and irritable bowel syndrome. Important components of inflammation are interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α), which are elevated both on the luminal and submucosal sides of the intestinal epithelial barrier in several diseases. Here, we developed a novel Escherichia coli based detection system for IFN-γ and TNF-α comprised of a chimeric protein and a simple signal transduction construct, which could be deployed on the luminal side of the intestine. OmpA of E. coli was engineered to detect IFN-γ or TNF-α through the replacement of extracellular loops with peptide fragments from OprF of P. aeruginosa. OmpA/OprF chimeras were developed, capable of binding IFN-γ or TNF-α. The specific peptide fragments that bind IFN-γ were identified. IFN-γ or TNF-α binding the OmpA/OprF chimera induced the pspA promoter, driving β-galactosidase production. The OmpA/OprF chimera had a detection limit of 300 pM for IFN-γ and 150 pM for TNF-α. This work will further the development of bacteria based therapeutics for the treatment of inflammatory diseases of the gut. PMID:26370067

  13. 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.

  14. Chronic hypoxia reduces adenosine A2A receptor-mediated inhibition of calcium current in rat PC12 cells via downregulation of protein kinase A.

    Science.gov (United States)

    Kobayashi, S; Beitner-Johnson, D; Conforti, L; Millhorn, D E

    1998-10-15

    1. Adenosine has been shown to decrease Ca2+ current (ICa) and attenuate the hypoxia-induced enhancement of intracellular free Ca2+ ([Ca2+]i) in oxygen-sensitive rat phaeochromocytoma (PC12) cells. These effects are mediated via the adenosine A2A receptor and protein kinase A (PKA). The current study was undertaken to determine the effects of adenosine on Ca2+ current and hypoxia-induced change in [Ca2+]i during chronic hypoxia. 2. Whole cell patch-clamp studies revealed that the effect of adenosine on ICa was significantly reduced when PC12 cells were exposed to hypoxia (10 % O2) for 24 and 48 h. 3. Ca2+ imaging studies using fura-2 revealed that the anoxia-induced increase in [Ca2+]i was significantly enhanced when PC12 cells were exposed to 10 % O2 for up to 48 h. In contrast, the inhibitory effects of adenosine on anoxia-induced elevation of [Ca2+]i was significantly blunted in PC12 cells exposed to hypoxia for 48 h. 4. Northern blot analysis revealed that mRNA for the A2A receptor, which is the only adenosine receptor subtype expressed in PC12 cells, was significantly upregulated by hypoxia. Radioligand binding analysis with [3H]CGS21680, a selective A2A receptor ligand, showed that the number of adenosine A2A receptor binding sites was similarly increased during exposure to 10% O2 for 48 h. 5. PKA enzyme activity was significantly inhibited when PC12 cells were exposed to 10% O2 for 24 and 48 h. However, we found that hypoxia failed to induce change in adenosine- and forskolin-stimulated adenylate cyclase enzyme activity. Chronic hypoxia also did not alter the immunoreactivity level of the G protein Gsalpha, an effector of the A2 signalling pathway. 6. Whole cell patch-clamp analysis showed that the effect of 8-bromo-cAMP, an activator of PKA, on ICa was significantly attenuated during 48 h exposure to 10% O2.7. We conclude therefore that the reduced effect of adenosine on ICa and [Ca2+]i in PC12 cells exposed to chronic hypoxia is due to hypoxia

  15. 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

  16. Oct4 mediates tumor initiating properties in oral squamous cell carcinomas through the regulation of epithelial-mesenchymal transition.

    Directory of Open Access Journals (Sweden)

    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.

  17. Tumor necrosis factor alpha production from CD8+ T cells mediates oviduct pathological sequelae following primary genital Chlamydia muridarum infection.

    Science.gov (United States)

    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.

  18. Interleukin-6- and Cyclic AMP-Mediated Signaling Potentiates Neuroendocrine Differentiation of LNCaP Prostate Tumor Cells

    Science.gov (United States)

    Deeble, Paul D.; Murphy, Daniel J.; Parsons, Sarah J.; Cox, Michael E.

    2001-01-01

    Neuroendocrine (NE) differentiation in prostatic adenocarcinomas has been reported to be an early marker for development of androgen independence. Secretion of mitogenic peptides from nondividing NE cells is thought to contribute to a more aggressive disease by promoting the proliferation of surrounding tumor cells. We undertook studies to determine whether the prostate cancer cell line LNCaP could be induced to acquire NE characteristics by treatment with agents that are found in the complex environment in which progression of prostate cancer towards androgen independence occurs. We found that cotreatment of LNCaP cells with agents that signal through cyclic AMP-dependent protein kinase (PKA), such as epinephrine and forskolin, and with the cytokine interleukin-6 (IL-6) promoted the acquisition of an NE morphological phenotype above that seen with single agents. Convergent IL-6 and PKA signaling also resulted in potentiated mitogen-activated protein kinase (MAPK) activation without affecting the level of signal transducer and activator of transcription or PKA activation observed with these agents alone. Cotreatment with epinephrine and IL-6 synergistically increased c-fos transcription as well as transcription from the β4 nicotinic acetylcholine receptor subunit promoter. Potentiated transcription from these elements was shown to be dependent on the MAPK pathway. Most importantly, cotreatment with PKA activators and IL-6 resulted in increased secretion of mitogenic neuropeptides. These results indicate that PKA and IL-6 signaling participates in gene transcriptional changes that reflect acquisition of an NE phenotype by LNCaP cells and suggest that similar signaling mechanisms, particularly at sites of metastasis, may be responsible for the increased NE content of many advanced prostate carcinomas. PMID:11713282

  19. Cell adhesion-mediated radioresistance (CAM-RR). Extracellular matrix-dependent improvement of cell survival in human tumor and normal cells in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Cordes, N.; Meineke, V. [Inst. of Radiobiology, Medical Academy of the German Armed Forces, Munich (Germany)

    2003-05-01

    Background: Cell-extracellular matrix (ECM) contact is thought to have great impact on cellular mechanisms resulting in increased cell survival upon exposure to ionizing radiation. Several human tumor cell lines and normal human fibroblastic cell strains of different origin, all of them expressing the wide-spread and important integrin subunit {beta}1, were irradiated, and clonogenic cell survival, {beta}1-integrin cell surface expression, and adhesive functionality were investigated. Material and Methods: Human tumor cell lines A172 (glioblastoma), PATU8902 (pancreas carcinoma), SKMES1 (lung carcinoma), A549 (lung carcinoma), and IPC298 (melanoma) as well as normal human skin (HSF1) and lung fibroblasts (CCD32) and human keratinocytes (HaCaT) were irradiated with 0-8 Gy. Besides colony formation assays, {beta}1-integrin cell surface expression by flow cytometry and adhesive functionality by adhesion assays were analyzed. Results: All cell lines showed improved clonogenic survival after irradiation in the presence of fibronectin as compared to plastic. Irradiated cells exhibited a significant, dose-dependent increase in {beta}1-integrin cell surface expression following irradiation. As a parameter of the adhesive functionality of the {beta}1-integrin, a radiation-dependent elevation of cell adhesion to fibronectin in comparison with adhesion to plastic was demonstrated. Conclusion: The in vitro cellular radiosensitivity is highly influenced by fibronectin according to the phenomenon of cell adhesion-mediated radioresistance. Additionally, our emerging data question the results of former and current in vitro cytotoxicity studies performed in the absence of an ECM. These findings might also be important for the understanding of malignant transformation, anchorage-independent cell growth, optimization of radiotherapeutic regimes and the prevention of normal tissue side effects on the basis of experimental radiobiological data. (orig.)

  20. Stress impairs the efficacy of immune stimulation by CpG-C: Potential neuroendocrine mediating mechanisms and significance to tumor metastasis and the perioperative period.

    Science.gov (United States)

    Levi, B; Matzner, P; Goldfarb, Y; Sorski, L; Shaashua, L; Melamed, R; Rosenne, E; Page, G G; Ben-Eliyahu, S

    2016-08-01

    We recently reported that immune stimulation can be compromised if animals are simultaneously subjected to stressful conditions. To test the generalizability of these findings, and to elucidate neuroendocrine mediating mechanisms, we herein employed CpG-C, a novel TLR-9 immune-stimulating agent. Animals were subjected to ongoing stress (20-h of wet cage exposure) during CpG-C treatment, and antagonists to glucocorticoids, β-adrenoceptor, COX2, or opioids were employed (RU486, nadolol, etodolac, naltrexone). In F344 rats, marginating-pulmonary NK cell numbers and cytotoxicity were studied, and the NK-sensitive MADB106 experimental metastasis model was used. In Balb/C mice, experimental hepatic metastases of the CT-26 colon tumor were studied; and in C57BL/6J mice, survival rates following excision of B16 melanoma was assessed - both mouse tumor models involved surgical stress. The findings indicated that simultaneous blockade of glucocorticoid and β-adrenergic receptors improved CpG-C efficacy against MADB106 metastasis. In mice bearing B16 melanoma, long-term survival rate was improved by CpG-C only when employed simultaneously with blockers of glucocorticoids, catecholamines, and prostaglandins. Prolonged stress impaired CpG-C efficacy in potentiating NK activity, and in resisting MADB106 metastasis in both sexes, as also supported by in vitro studies. This latter effect was not blocked by any of the antagonists or by adrenalectomy. In the CT26 model, prolonged stress only partially reduced the efficacy of CpG-C. Overall, our findings indicate that ongoing behavioral stress and surgery can jeopardize immune-stimulatory interventions and abolish their beneficial metastasis-reducing impacts. These findings have implications for the clinical setting, which often involve psychological and physiological stress responses during immune-stimulation. PMID:26944000

  1. Tumor necrosis factor-α and lymphotoxin-α mediate myocardial ischemic injury via TNF receptor 1, but are cardioprotective when activating TNF receptor 2.

    Directory of Open Access Journals (Sweden)

    Yanqing Zhang

    Full Text Available OBJECTIVE: This study determines the roles of tumor necrosis factor-α (TNFα and lymphotoxin-α (LTα in post-myocardial infarction (post-MI cardiac injury, and identifies the TNF receptor type responsible for TNFα- and LTα-mediated cardiac injury. METHODS AND RESULTS: Adult male wild type (WT, TNFα(-/-, LTα(-/-, TNFR1(-/-, and TNFR2(-/- mice were subjected to MI via coronary artery occlusion. Functional, histological, and biochemical analyses were performed 1 to 7 days post-MI. In WT mice, MI significantly increased both TNFα and LTα levels in plasma, but in distinct temporal manner. Plasma TNFα peaked 1 day after MI, and decreased toward baseline 3 days after MI. In contrast, plasma LTα became significantly increased 3 days post-MI, and remained elevated thereafter. TNFα deletion significantly improved cardiac function 3 days, but not 7 days, after MI. In contrast, LTα deletion had no effect upon cardiac dysfunction 3 days after MI, but improved cardiac function 7 days after MI. More importantly, knockout of TNFR1 and TNFR2 had opposite effects upon post-MI cardiac dysfunction, which was markedly attenuated by TNFR1 deletion (P<0.01 vs. WT, but exacerbated by TNFR2 deletion (P<0.05 vs. WT. CONCLUSION: Our study demonstrates that TNFα and LTα overproduction contribute to early and late cardiac dysfunction after MI, respectively. We provide clear evidence that both TNFα and LTα mediate post-MI cardiac dysfunction via TNFR1 stimulation, whereas TNFR2 activation is cardioprotective against ischemic injury. Simultaneous inhibition of TNFα and LTα or specific TNFR1 function blockade may represent superior cardioprotective approaches over general TNF activity suppression.

  2. ENO1 promotes tumor proliferation and cell adhesion mediated drug resistance (CAM-DR) in Non-Hodgkin's Lymphomas

    Energy Technology Data Exchange (ETDEWEB)

    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.

  3. Transferrin-PEG-PE modified dexamethasone conjugated cationic lipid carrier mediated gene delivery system for tumor-targeted transfection

    Directory of Open Access Journals (Sweden)

    Wang W

    2012-05-01

    Full Text Available Wei Wang,1 Fang Zhou,2 Linfu Ge,2 Ximin Liu,2 Fansheng Kong21Department of Chinese Medicine Integrated Traditional Chinese Medicine and Western Medicine, General Hospital of Ji’nan Command, Ji’nan, China; 2Department of Hematology, General Hospital of Ji’nan Command, Ji’nan, ChinaBackground: 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.Keywords: gene delivery, active targeting, transferrin-PEG-PE, dexamethasone conjugated lipid, nuclear localization

  4. Extracellular signal-regulated kinase 2 (ERK-2) mediated phosphorylation regulates nucleo-cytoplasmic shuttling and cell growth control of Ras-associated tumor suppressor protein, RASSF2

    Energy Technology Data Exchange (ETDEWEB)

    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

  5. 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 cellular gene expression in a bystander fashion. Methods We were interested to study whether exogenous exposure to HIV-1 Tat-C protein perturbs the microRNA (miRNA expression profile of human microglial cells, leading to altered protein expression. We used protein expression and purification, miRNA overexpression, miRNA knockdown, transfection, site-directed mutagenesis, real-time PCR, luciferase assay and western blotting techniques to perform our study. Results HIV-1 Tat-C treatment of human microglial cells resulted in a dose-dependent increase in miR-32 expression. We found that tumor necrosis factor-receptor–associated factor 3 TRAF3 is a direct target for miR-32, and overexpression of miR-32 in CHME3 cells decreased TRAF3 both at the mRNA and the protein level. Recovery of TRAF3 protein expression after transfection of anti-miR-32 and the results of the luciferase reporter assay provided direct evidence of TRAF3 regulation by miR-32. We found that the regulation of interferon regulatory factor 3 (IRF3 and IRF7 is controlled by cellular levels of TRAF3 protein in microglial cells, as after overexpression of miR-32 and application of anti-miR-32, expression levels of IRF3 and IRF7 were inversely regulated by expression levels of TRAF3. Thus, our results suggest a novel miRNA mediated mechanism for regulation of TRAF3 in human microglial cells exposed to HIV-1 Tat C protein. These results may help to elucidate the detrimental neuroinflammatory consequences of HIV-1 Tat C protein in bystander fashion. Conclusion HIV-1 Tat protein can modulate TRAF3 expression through

  6. Tumor Necrosis Factor-α and Interleukin-6: Potential Interorgan Inflammatory Mediators Contributing to Destructive Periodontal Disease in Obesity or Metabolic Syndrome

    Directory of Open Access Journals (Sweden)

    Roozbeh Khosravi

    2013-01-01

    Full Text Available Obesity has become a worldwide health burden in the last two decades. Obesity has been associated with increased comorbidities, such as coronary artery disease, diabetes, and destructive periodontal disease. Obesity is also part of a group of risk factors occurring together in an individual, which is referred to as metabolic syndrome. Clinical studies have shown higher risk for destructive periodontal disease in obesity and metabolic syndrome. However, the role of obesity and metabolic syndrome in the onset and development of destructive periodontal disease has not yet been fully understood. In this review, we discuss a working model, which focuses on interorgan inflammation as a common etiological factor for destructive periodontal disease associated with obesity and metabolic syndrome. Specifically, we suggest that elevated levels of tumor necrosis factor-α (TNF-α or interleukin 6 (IL-6—both adipokines and known risk factors for destructive periodontal disease—in obesity and metabolic syndrome contribute to the onset and development of destructive periodontal disease. The connections between destructive periodontal disease and systemic conditions, such as obesity or metabolic syndrome, are complex and potentially multidirectional. This review largely focuses on TNF-α and IL-6, inflammatory mediators, as potential common risk factors and does not exclude other biological mechanisms.

  7. Mechanism of nuclear factor of activated T-cells mediated FasL expression in corticosterone -treated mouse Leydig tumor cells

    Directory of Open Access Journals (Sweden)

    Wang Qian

    2008-06-01

    Full Text Available Abstract Background Fas and FasL is important mediators of apoptosis. We have previously reported that the stress levels of corticosterone (CORT, glucocorticoid in rat increase expression of Fas/FasL and activate Fas/FasL signal pathway in rat Leydig cells, which consequently leads to apoptosis. Moreover, our another study showed that nuclear factor of activated T-cells (NFAT may play a potential role in up-regulation of FasL during CORT-treated rat Leydig cell. It is not clear yet how NFAT is involved in CORT-induced up-regulation of FasL. The aim of the present study is to investigate the molecular mechanisms of NFAT-mediated FasL expression in CORT-treated Leydig cells. Results Western blot analysis showed that NFAT2 expression is present in mouse Leydig tumor cell (mLTC-1. CORT-induced increase in FasL expression in mLTC-1 was ascertained by Western Blot analysis and CORT-induced increase in apoptotic frequency of mLTC-1 cells was detected by FACS with annexin-V labeling. Confocal imaging of NFAT2-GFP in mLTC-1 showed that high level of CORT stimulated NFAT translocation from the cytoplasm to the nucleus. RNA interference-mediated knockdown of NFAT2 significantly attenuated CORT-induced up-regulation of FasL expression in mLTC. These results corroborated our previous finding that NFAT2 is involved in CORT-induced FasL expression in rat Leydig cells and showed that mLTC-1 is a suitable model for investigating the mechanism of CORT-induced FasL expression. The analysis of reporter constructs revealed that the sequence between -201 and +71 of mouse FasL gene is essential for CORT-induced FasL expression. The mutation analysis demonstrated that CORT-induced FasL expression is mediated via an NFAT binding element located in the -201 to +71 region. Co-transfection studies with an NFAT2 expression vector and reporter construct containing -201 to +71 region of FasL gene showed that NFAT2 confer a strong inducible activity to the FasL promoter at its

  8. Regulation of Calcium-Independent Phospholipase A2 Expression by Adrenoceptors and Sterol Regulatory Element Binding Protein-Potential Crosstalk Between Sterol and Glycerophospholipid Mediators.

    Science.gov (United States)

    Chew, Wee-Siong; Ong, Wei-Yi

    2016-01-01

    Calcium-independent phospholipase A2 (iPLA2) is an 85-kDa enzyme that releases docosahexaenoic acid (DHA) from glycerophospholipids. DHA can be metabolized to resolvins and neuroprotectins that have anti-inflammatory properties and effects on neural plasticity. Recent studies show an important role of prefrontal cortical iPLA2 in hippocampo-prefrontal cortical LTP and antidepressant-like effect of the norepinephrine reuptake inhibitor (NRI) antidepressant, maprotiline. In this study, we elucidated the cellular mechanisms through which stimulation of adrenergic receptors could lead to increased iPLA2 expression. Treatment of SH-SY5Y neuroblastoma cells with maprotiline, another tricyclic antidepressant with noradrenaline reuptake inhibiting properties, nortriptyline, and the adrenergic receptor agonist, phenylephrine, resulted in increased iPLA2β mRNA expression. This increase was blocked by inhibitors to alpha-1 adrenergic receptor, mitogen-activated protein (MAP) kinase or extracellular signal-regulated kinase (ERK) 1/2, and sterol regulatory element-binding protein (SREBP). Maprotiline and phenylephrine induced binding of SREBP-2 to sterol regulatory element (SRE) region on the iPLA2 promoter, as determined by electrophoretic mobility shift assay (EMSA). Together, results indicate that stimulation of adrenoreceptors causes increased iPLA2 expression via MAP kinase/ERK 1/2 and SREBP, and suggest a possible mechanism for effect of CNS noradrenaline on neural plasticity and crosstalk between sterol and glycerophospholipid mediators, that may play a role in physiological or pathophysiological processes in the brain and other organs.

  9. Caffeine inhibits the activation of hepatic stellate cells induced by acetaldehyde via adenosine A2A receptor mediated by the cAMP/PKA/SRC/ERK1/2/P38 MAPK signal pathway.

    Directory of Open Access Journals (Sweden)

    He Wang

    Full Text Available Hepatic stellate cell (HSC activation is an essential event during alcoholic liver fibrosis. Evidence suggests that adenosine aggravates liver fibrosis via the adenosine A2A receptor (A2AR. Caffeine, which is being widely consumed during daily life, inhibits the action of adenosine. In this study, we attempted to validate the hypothesis that caffeine influences acetaldehyde-induced HSC activation by acting on A2AR. Acetaldehyde at 50, 100, 200, and 400 μM significantly increased HSC-T6 cells proliferation, and cell proliferation reached a maximum at 48 h after exposure to 200 μM acetaldehyde. Caffeine and the A2AR antagonist ZM241385 decreased the cell viability and inhibited the expression of procollagen type I and type III in acetaldehyde-induced HSC-T6 cells. In addition, the inhibitory effect of caffeine on the expression of procollagen type I was regulated by A2AR-mediated signal pathway involving cAMP, PKA, SRC, and ERK1/2. Interestingly, caffeine's inhibitory effect on the expression of procollagen type III may depend upon the A2AR-mediated P38 MAPK-dependent pathway.Caffeine significantly inhibited acetaldehyde-induced HSC-T6 cells activation by distinct A2AR mediated signal pathway via inhibition of cAMP-PKA-SRC-ERK1/2 for procollagen type I and via P38 MAPK for procollagen type III.

  10. Combined Flt3L/TK Gene Therapy Induces Immunological Surveillance Which Mediates an Immune Response Against a Surrogate Brain Tumor Neoantigen

    OpenAIRE

    King, Gwendalyn D; Muhammad, AKM Ghulam; Larocque, Daniel; Kelson, Kyle R; Xiong, Weidong; Liu, Chunyan; Sanderson, Nicholas SR; Kroeger, Kurt M.; Castro, Maria G; Pedro R Lowenstein

    2011-01-01

    Glioblastoma multiforme (GBM) is a primary brain tumor with a median survival of 14.6 months postdiagnosis. The infiltrative nature of GBM prevents complete resection and residual brain tumor cells give rise to recurrent GBM, a hallmark of this disease. Recurrent GBMs are known to harbor numerous mutations/gene rearrangements when compared to the primary tumor, which leads to the potential expression of novel proteins that could serve as tumor neoantigens. We have developed a combined immune-...

  11. Intravesical Bacillus Calmette-Guérin therapy for murine bladder tumors: initiation of the response by fibronectin-mediated attachment of Bacillus Calmette-Guérin.

    Science.gov (United States)

    Ratliff, T L; Palmer, J O; McGarr, J A; Brown, E J

    1987-04-01

    Intravesical Bacillus Calmette-Guérin (BCG) is considered to be one of the most effective treatments for superficial bladder cancer. Although the mechanisms by which BCG inhibits tumor growth are not known, previous studies have shown that systemic immunization to BCG and the local expression of the immune response in the bladder are associated with a favorable response to BCG therapy. We have investigated the conditions required for the initiation of an immunological response after the intravesical instillation of BCG. Initial histological studies showed that BCG attached to the bladder wall only in areas where the urothelium was damaged by electrocautery and suggested that attachment was associated with the fibrin clot. Quantitative studies verified the histological observations. Minimal BCG attachment (mean less than 10(2) colony forming units) was observed in normal bladders in contrast with a mean of 1.42 X 10(4) colony forming units/bladder in bladders damaged by electrocautery (10 separate experiments). BCG attachment to the bladder wall was durable since organisms were observed in bladders 48 h after instillation. To investigate the proteins to which BCG attached, we tested the binding of BCG to extracellular matrix and inflammatory proteins which comprise a significant portion of the fibrin clot. BCG bound in vitro to coverslips coated in vivo with extracellular matrix proteins but did not bind to control albumin-coated coverslips. BCG also bound to coverslips coated with purified plasma fibronectin but not to coverslips coated with other purified extracellular matrix proteins including laminin, fibrinogen, and type IV collagen. BCG attachment to coverslips coated with either extracellular matrix proteins or purified fibronectin was inhibited by antibodies specific for fibronectin. Moreover, BCG attachment to cauterized bladders in vivo was inhibited by antifibronectin antibodies. These results demonstrate that fibronectin mediates the attachment of BCG

  12. Hemozoin triggers tumor necrosis factor alpha-mediated re-lease of lysozyme by human adherent monocytes:new evi-dences on leukocyte degranulation in P.falciparum malaria

    Institute of Scientific and Technical Information of China (English)

    Prato M; Giribaldi G; Arese P

    2009-01-01

    Objective:Avidly phagocytosed hemozoin (malarial pigment)alters several functions of human monocytes and stimulates generation of several cytokines.Recently,we showed that phagocytosis of hemozoin by human mono-cytes increases expression and activity of matrix metalloproteinase-9,a proteolytic enzyme available in specific gelatinase granules,which contain several enzymes including lysozyme.Present work investigated active lyso-zyme release after phagocytosis of hemozoin and its dependence on production of tumor necrosis factor alpha. Methods:After phagocytosis of hemozoin,hemozoin-containing trophozoites or control meals (opsonized non-parasitized red blood cells and latex particles),monocyte supernatants were monitored for 2 hours,in presence of blocking anti-human tumor necrosis factor alpha antibodies or recombinant human tumor necrosis factor alpha cytokine in selected experiments.Lysozyme release was evaluated by a specific spectrometric assay measuring lysozyme activity after coincubation of cell supernatants with suspensions of Mycrococcus Lysodeikticus,while levels of soluble tumor necrosis factor alpha were analyzed by specific enzyme-linked immunodsorbent assay. Results:Levels of lysozyme activity and soluble tumor necrosis factor alpha protein were increased in hemozo-in-or trophozoites-laden monocytes supernatants.Phagocytosis per se (control meals)also increased lysozyme release,but levels were significantly lower than those obtained after phagocytosis of hemozoin or trophozoites. Interestingly,all effects on lysozyme release observed after phagocytosis were abrogated by blocking anti-human tumor necrosis factor alpha antibodies,while they were mimicked by recombinant human tumor necrosis factor alpha cytokine.Conclusions:Present work shows that phagocytosis of hemozoin promotes monocyte degranula-tion and enhances active lysozyme release.The effect requires tumor necrosis factor alpha mediation.

  13. Inhibiting HER3-mediated tumor cell growth with affibody molecules engineered to low picomolar affinity by position-directed error-prone PCR-like diversification.

    Science.gov (United States)

    Malm, Magdalena; Kronqvist, Nina; Lindberg, Hanna; Gudmundsdotter, Lindvi; Bass, Tarek; Frejd, Fredrik Y; Höidén-Guthenberg, Ingmarie; Varasteh, Zohreh; Orlova, Anna; Tolmachev, Vladimir; Ståhl, Stefan; Löfblom, John

    2013-01-01

    The HER3 receptor is implicated in the progression of various cancers as well as in resistance to several currently used drugs, and is hence a potential target for development of new therapies. We have previously generated Affibody molecules that inhibit heregulin-induced signaling of the HER3 pathways. The aim of this study was to improve the affinity of the binders to hopefully increase receptor inhibition efficacy and enable a high receptor-mediated uptake in tumors. We explored a novel strategy for affinity maturation of Affibody molecules that is based on alanine scanning followed by design of library diversification to mimic the result from an error-prone PCR reaction, but with full control over mutated positions and thus less biases. Using bacterial surface display and flow-cytometric sorting of the maturation library, the affinity for HER3 was improved more than 30-fold down to 21 pM. The affinity is among the higher that has been reported for Affibody molecules and we believe that the maturation strategy should be generally applicable for improvement of affinity proteins. The new binders also demonstrated an improved thermal stability as well as complete refolding after denaturation. Moreover, inhibition of ligand-induced proliferation of HER3-positive breast cancer cells was improved more than two orders of magnitude compared to the previously best-performing clone. Radiolabeled Affibody molecules showed specific targeting of a number of HER3-positive cell lines in vitro as well as targeting of HER3 in in vivo mouse models and represent promising candidates for future development of targeted therapies and diagnostics.

  14. Human recombinant interleukin-1 beta- and tumor necrosis factor alpha-mediated suppression of heparin-like compounds on cultured porcine aortic endothelial cells

    International Nuclear Information System (INIS)

    Cytokines are known to tip the balance of the coagulant-anticoagulant molecules on the endothelial cell surface toward intravascular coagulation. Their effects on endothelial cell surface-associated heparin-like compounds have not been examined yet. Incorporation of [35S]sulfate into heparan sulfate on cultured porcine aortic endothelial cells was suppressed by human recombinant interleukin-1 beta (rIL-1 beta) or tumor necrosis factor alpha (rTNF alpha) in a dose- and time-dependent manner with little effect on cell number, protein content, and [3H]leucine incorporation of cells. Maximal inhibition was achieved by incubation of cells with 100 ng/ml of rIL-1 beta or 5 ng/ml of rTNF alpha for 12-24 hours, resulting in a reduction of the synthesis of heparan sulfate on the cell surface by approximately 50%. The dose dependency was consistent with that seen in the stimulation of endothelial cell procoagulant activity by each cytokine. The suppression of heparan sulfate synthesis was sustained for at least 48 hours after pretreatment of cells with cytokines and was unchanged after the addition of indomethacin or polymyxin B. The rate of degradation of prelabeled 35S-heparan sulfate on the cell surface was not altered by cytokine treatments. Neither the size, the net negative charge, nor the proportion of the molecule with high affinity for antithrombin III of endothelial cell heparan sulfate was changed by cytokines. Furthermore, specific binding of 125I-labeled antithrombin III to the endothelial cell surface was reduced to 40-60% of control by cytokines. In parallel with reduction in binding, antithrombin III cofactor activity was partially diminished in cytokine-treated endothelial cells. Thus, cytokine-mediated suppression of heparin-like substance on endothelial cells appears to be another cytokine-inducible endothelial effects affecting coagulation

  15. Infliximab ameliorating depression-like behavior through inhibiting the activation of the IDO-HAAO pathway mediated by tumor necrosis factor-α in a rat model.

    Science.gov (United States)

    Fu, Xiao-Yan; Li, Hai-Yan; Jiang, Qing-Song; Cui, Ting; Jiang, Xin-Hui; Zhou, Qi-Xin; Qiu, Hong-Mei

    2016-09-01

    In recent years, some studies have suggested that the activation of inflammatory system plays a role in the occurrence of depression. Tumor necrosis factor-α (TNF-α), as one of the preinflammatory cytokines, has been reported to be involved in the occurrence of various diseases including depression. Infliximab, an antagonist of TNF-α, is usually used to treat some autoimmune diseases such as Crohn's disease and can perhaps be used to treat other diseases. In this study, the antidepressant effect and a possible mechanism of infliximab were investigated by studying the depression-like behavior and expression of TNF-α, indoleamine 2, 3-dioxygenase (IDO), and 3-hydroxyl amino acid oxygenase (HAAO) from the cortex and hippocampus in rat exposed to chronic unpredicted stress. Forty male Sprague-Dawley rats were divided into a control group (CG), an infliximab-treated control group, a model group (MG), and an infliximab-treated model group (IFXM). Infliximab (5 mg/kg once week) was administered to the infliximab-treated control group and IFXM rats by an intraperitoneal injection, whereas an equivalent volume of vehicle was administered to CG and MG rats. Rat behaviors and the expression of TNF-α, IDO, and HAAO in the cortex and hippocampus were determined. It was found that a significant relief in depression-like behaviors was observed with a downregulation of TNF-α, IDO, and HAAO expression in the IFXM rats compared with MG rats. The results show the antidepressant effect of infliximab and suggest that its mechanism is partly related to inhibition of IDO-HAAO pathway activation mediated by TNF-α in rat brain. PMID:27366867

  16. Ga-66 labeled somatostatin analogue DOTA-DPhe1-Tyr3-octreotide as a potential agent for positron emission tomography imaging and receptor mediated internal radiotherapy of somatostatin receptor positive tumors

    International Nuclear Information System (INIS)

    Radionuclide labeled somatostatin analogues selectively target somatostatin receptor (SSTR)-expressing tumors as a basis for diagnosis and treatment of these tumors. Recently, a DOTA-functionalized somatostatin analogue, DOTATOC (DOTA-DPhe1-Tyr3-octreotide) has been developed. This compound has been shown to be superior to the other somatostatin analogues as indicated by its uniquely high tumor-to-non-target tissue ratio. DOTATOC can be labeled with a variety of radiometals including gallium radioisotopes. Gallium-66 is a positron emitting radionuclide (T1/2 =9.5 hr; β+=56%), that can be produced in carrier free form by a low-beam energy cyclotron. In this study we investigated SSTR targeting characteristics of 66Ga-DOTATOC in AR42J rat pancreas tumor implanted nude mice as a potential agent for diagnosis and receptor-mediated internal radiotherapy of SSTR-expressing tumors. We compared our results with 67Ga- and 68Ga- labeled DOTATOC. The radiolabeling procedure gave labeling yield ranged from 85-95% and radiochemical and chemical purity was >95%. In-vitro competitive binding curves and in-vivo competitive displacement studies with an excess of unlabeled peptide indicates that there is specific binding of the radioligand to SSTR. Animal biodistribution data and serial microPETTM images demonstrated rapid tumor uptake and rapid clearance from the blood and all tissues except kidney. Maximum % ID/g values for tumor were 10.0±0.7, 13.2±2.1 and 9.8±1.5 for 66Ga-, 67Ga-, and 68Ga-DOTATOC, respectively. Calculated tumor, kidney and bone marrow doses for 66Ga-DOTATOC based on biodistribution data were 178, 109 and 1.2 cGy/MBq, respectively. We conclude that 66Ga labeled DOTATOC can be used for PET diagnosis and quantitative imaging-based dosimetry of SSTR positive tumors. 66Ga-DOTATOC may also be used in higher doses for ablation of these tumors. However, kidney is the critical organ for toxicity (tumor/kidney ratio 1.64), and high kidney uptake must be eliminated

  17. Active treatment of murine tumors with a highly attenuated vaccinia virus expressing the tumor associated antigen 5T4 (TroVax) is CD4+ T cell dependent and antibody mediated.

    Science.gov (United States)

    Harrop, Richard; Ryan, Matthew G; Myers, Kevin A; Redchenko, Irina; Kingsman, Susan M; Carroll, Miles W

    2006-09-01

    5T4 is a tumor associated antigen that is expressed on the surface of a wide spectrum of human adenocarcinomas. The highly attenuated virus, modified vaccinia Ankara, has been engineered to express human 5T4 (h5T4). In a pre-clinical murine model, the recombinant virus (TroVax) induces protection against challenge with CT26-h5T4 (a syngeneic tumor line expressing h5T4). Anti-tumor activity is long lived, with protection still evident 6 months after the final vaccination. In a therapeutic setting, injection of mice with TroVax results in a reduction in tumor burden of >90%. Depletion of CD8+ T cells has no effect upon therapy in the active treatment model, whereas depletion of CD4+ T cells completely abrogates anti-tumor activity. In a prophylactic setting, depletion of CD4+ and CD8+ T cells after the induction of a h5T4 immune response has no deleterious effect on protection following challenge with CT26-h5T4. In light of these studies, the role of antibodies in protection against tumor challenge was investigated. 5T4 specific polyclonal serum decreased tumor burden by approximately 70%. Thus, we conclude that CD4+ T cells are essential for the induction of a protective immune response and that antibodies are the likely effector moiety in this xenogeneic murine tumor model. PMID:16311730

  18. Expression analysis of mammaglobin A (SCGB2A2 and lipophilin B (SCGB1D2 in more than 300 human tumors and matching normal tissues reveals their co-expression in gynecologic malignancies

    Directory of Open Access Journals (Sweden)

    Kristiansen Glen

    2006-04-01

    Full Text Available Abstract Background Mammaglobin A (SCGB2A2 and lipophilin B (SCGB1D2, two members of the secretoglobin superfamily, are known to be co-expressed in breast cancer, where their proteins form a covalent complex. Based on the relatively high tissue-specific expression pattern, it has been proposed that the mammaglobin A protein and/or its complex with lipophilin B could be used in breast cancer diagnosis and treatment. In view of these clinical implications, the aim of the present study was to analyze the expression of both genes in a large panel of human solid tumors (n = 309, corresponding normal tissues (n = 309 and cell lines (n = 11, in order to evaluate their tissue specific expression and co-expression pattern. Methods For gene and protein expression analyses, northern blot, dot blot hybridization of matched tumor/normal arrays (cancer profiling arrays, quantitative RT-PCR, non-radioisotopic RNA in situ hybridization and immunohistochemistry were used. Results Cancer profiling array data demonstrated that mammaglobin A and lipophilin B expression is not restricted to normal and malignant breast tissue. Both genes were abundantly expressed in tumors of the female genital tract, i.e. endometrial, ovarian and cervical cancer. In these four tissues the expression pattern of mammaglobin A and lipophilin B was highly concordant, with both genes being down-, up- or not regulated in the same tissue samples. In breast tissue, mammaglobin A expression was down-regulated in 49% and up-regulated in 12% of breast tumor specimens compared with matching normal tissues, while lipophilin B was down-regulated in 59% and up-regulated in 3% of cases. In endometrial tissue, expression of mammaglobin A and lipophilin B was clearly up-regulated in tumors (47% and 49% respectively. Both genes exhibited down-regulation in 22% of endometrial tumors. The only exceptions to this concordance of mammaglobin A/lipophilin B expression were normal and malignant tissues of

  19. P2X7 receptor activation ameliorates CA3 neuronal damage via a tumor necrosis factor-α-mediated pathway in the rat hippocampus following status epilepticus

    Directory of Open Access Journals (Sweden)

    Ryu Hea Jin

    2011-06-01

    Full Text Available Abstract Background The release of tumor necrosis factor-α (TNF-α appears depend on the P2X7 receptor, a purinergic receptor. In the present study, we addressed the question of whether P2X7 receptor-mediated TNF-α regulation is involved in pathogenesis and outcome of status epilepticus (SE. Methods SE was induced by pilocarpine in rats that were intracerebroventricularly infused with saline-, 2',3'-O-(4-benzoylbenzoyl-adenosine 5'-triphosphate (BzATP, adenosine 5'-triphosphate-2',3'-dialdehyde (OxATP, A-438079, or A-740003 prior to SE induction. Thereafter, we performed Fluoro-Jade B staining and immunohistochemical studies for TNF-α and NF-κB subunit phosphorylations. Results Following SE, P2X7 receptor agonist (BzATP infusion increased TNF-α immunoreactivity in dentate granule cells as compared with that in saline-infused animals. In addition, TNF-α immunoreactivity was readily apparent in the mossy fibers, while TNF-α immunoreactivity in CA1-3 pyramidal cells was unaltered. However, P2X7 receptor antagonist (OxATP-, A-438079, and A-740003 infusion reduced SE-induced TNF-α expression in dentate granule cells. In the CA3 region, BzATP infusion attenuated SE-induced neuronal damage, accompanied by enhancement of p65-Ser276 and p65-Ser311 NF-κB subunit phosphorylations. In contrast, OxATP-, A-438079, and A-740003 infusions increased SE-induced neuronal death. Soluble TNF p55 receptor (sTNFp55R, and cotreatment with BzATP and sTNFp55R infusion also increased SE-induced neuronal damage in CA3 region. However, OxATP-, sTNFp55R or BzATP+sTNFp55R infusions could not exacerbate SE-induced neuronal damages in the dentate gyrus and the CA1 region, as compared to BzATP infusion. Conclusions These findings suggest that TNF-α induction by P2X7 receptor activation may ameliorate SE-induced CA3 neuronal damage via enhancing NF-κB p65-Ser276 and p65-Ser311 phosphorylations.

  20. Anti-tumor necrosis factor-α therapy and changes of flow-mediated vasodilatation in psoriatic and rheumatoid arthritis patients.

    Science.gov (United States)

    Mazzoccoli, Gianluigi; Notarsanto, Incoronata; de Pinto, Gennaro Davide; Dagostino, Mariangela Pia; De Cata, Angelo; D'Alessandro, Giuseppe; Tarquini, Roberto; Vendemiale, Gianluigi

    2010-12-01

    For a long time, the endothelial covering of the vessels has been considered an inert surface. On the contrary, the endothelial cells are active and dynamic elements in the interaction between blood and tissues. The control of the vessel basal tone is obtained by the complex balance between the relaxing and contracting endothelial factors. Previous clinical studies show that patients suffering from rheumatoid arthritis and other autoimmune rheumatologic pathologies are at high risk of death being prematurely affected by atherosclerosis and cardiovascular diseases. Blocking tumor necrosis factor (TNF)-α by biological drugs improves the endothelial function. The aim of our study was to evaluate the effects of two anti-TNF-α drugs (infliximab and etanercept) on the endothelial function by evaluating the flow-mediated dilatation (FMD), which was measured in the brachial artery before and after treatment and after 8-12 weeks. We enrolled 36 patients (average age 52 ± 9.8 years, 12 men and 24 women), 25 of them were affected by rheumatoid arthritis (RA) and 11 were affected by psoriatic arthritis (PsA) and they were divided into three groups: 10 patients were treated with etanercept, 13 patients were treated with infliximab, 13 patients were treated with DMARDs. We measured the common carotid intimal-medial thickness (ccIMT) and the endothelial function was evaluated by FMD measurement in the brachial artery, before treatment, 1 h after the beginning of treatment and after 8-12 weeks. No statistically significant difference between the three groups was found for the ultrasonographic evaluation of the carotid IMT. On the contrary, the differences between FMD values before and after the treatment in the patients treated with etanercept (13.1 ± 0.01 vs. 18.8 ± 0.01%, p biological drugs in patients affected by autoimmune arthritis can modify the endothelial function, as indicated by the induced FMD changes, but the long-term effect tends to be considerably

  1. The Major Prognostic Features of Nuclear Receptor NR5A2 in Infiltrating Ductal Breast Carcinomas

    Directory of Open Access Journals (Sweden)

    Li-Yun Chang

    2015-01-01

    Full Text Available Background. Gene expression profiles of 181 breast cancer samples were analyzed to identify prognostic features of nuclear receptors NR5A1 and NR5A2 based upon their associated transcriptional networks. Methods. A supervised network analysis approach was used to build the NR5A-mediated transcriptional regulatory network. Other bioinformatic tools and statistical methods were utilized to confirm and extend results from the network analysis methodology. Results. NR5A2 expression is a negative factor in breast cancer prognosis in both ER(− and ER(−/ER(+ mixed cohorts. The clinical and cohort significance of NR5A2-mediated transcriptional activities indicates that it may have a significant role in attenuating grade development and cancer related signal transduction pathways. NR5A2 signature that conditions poor prognosis was identified based upon results from 15 distinct probes. Alternatively, the expression of NR5A1 predicts favorable prognosis when concurrent NR5A2 expression is low. A favorable signature of eight transcription factors mediated by NR5A1 was also identified. Conclusions. Correlation of poor prognosis and NR5A2 activity is identified by NR5A2-mediated 15-gene signature. NR5A2 may be a potential drug target for treating a subset of breast cancer tumors across breast cancer subtypes, especially ER(− breast tumors. The favorable prognostic feature of NR5A1 is predicted by NR5A1-mediated 8-gene signature.

  2. Tumor penetrating peptides

    Directory of Open Access Journals (Sweden)

    Tambet eTeesalu

    2013-08-01

    Full Text Available Tumor-homing peptides can be used to deliver drugs into tumors. Phage library screening in live mice has recently identified homing peptides that specifically recognize the endothelium of tumor vessels, extravasate, and penetrate deep into the extravascular tumor tissue. The prototypic peptide of this class, iRGD (CRGDKGPDC, contains the integrin-binding RGD motif. RGD mediates tumor homing through binding to αv integrins, which are selectively expressed on various cells in tumors, including tumor endothelial cells. The tumor-penetrating properties of iRGD are mediated by a second sequence motif, R/KXXR/K. This C-end Rule (or CendR motif is active only when the second basic residue is exposed at the C-terminus of the peptide. Proteolytic processing of iRGD in tumors activates the cryptic CendR motif, which then binds to neuropilin-1 activating an endocytic bulk transport pathway through tumor tissue. Phage screening has also yielded tumor-penetrating peptides that function like iRGD in activating the CendR pathway, but bind to a different primary receptor. Moreover, novel tumor-homing peptides can be constructed from tumor-homing motifs, CendR elements and protease cleavage sites. Pathologies other than tumors can be targeted with tissue-penetrating peptides, and the primary receptor can also be a vascular zip code of a normal tissue. The CendR technology provides a solution to a major problem in tumor therapy, poor penetration of drugs into tumors. The tumor-penetrating peptides are capable of taking a payload deep into tumor tissue in mice, and they also penetrate into human tumors ex vivo. Targeting with these peptides specifically increases the accumulation in tumors of a variety of drugs and contrast agents, such as doxorubicin, antibodies and nanoparticle-based compounds. Remarkably the drug to be targeted does not have to be coupled to the peptide; the bulk transport system activated by the peptide sweeps along any compound that is

  3. T-cell-receptor engagement and tumor ICAM-1 up-regulation are required to by-pass low susceptibility of melanoma cells to autologous CTL-mediated lysis.

    Science.gov (United States)

    Anichini, A; Mortarini, R; Alberti, S; Mantovani, A; Parmiani, G

    1993-04-01

    Tumor-specific and non-specific CD3+, TcR alpha beta+, CD8+ cytotoxic T-cell (CTL) clones, isolated from tumor-infiltrating lymphocytes (TIL) or peripheral blood lymphocytes (PBL) of a melanoma patient and allogeneic LAK cells, were used to investigate the requirements for bypassing the low lysability of some melanoma clones derived from an s.c. metastasis from which highly lysable clones were also obtained. Cytofluorimetric analysis showed that all melanoma clones expressed ICAM-1, although to different extents, reaching a 10-fold difference in fluorescence units, while HLA class-I antigens were similarly expressed. The differences in expression of ICAM-1 among tumor clones correlated with differences in lysability, by both specific and non-specific CTL, but were not large enough to affect lymphocyte-tumor conjugate formation. Cytokine- or gene-transfer-mediated up-regulation of ICAM-1 did not induce de novo lysis of ICAM-1low tumor cells; however, it markedly enhanced a low level of killing of the same cells by tumor-specific, TcR-dependent and HLA-restricted CTL clones but not by non-specific, TcR-independent effectors. In addition, lysis of melanoma clones by any effector was similarly inhibited by anti-ICAM-1 and anti-LFA-1 antibodies. This indicates that by-pass of low lysability of ICAM-1low melanoma clones by CTL clones, after ICAM-1 up-regulation, is possible only if simultaneous LFA-1 and TcR engagement takes place. In addition, these results suggest that the constitutive high level of expression of ICAM-1 on the subset of ICAM-1high melanoma cells must be only one of the factors contributing to the high lysability of these cells by any effector.

  4. A simple protocol for preparation of a liposomal vesicle with encapsulated plasmid DNA that mediate high accumulation and reporter gene activity in tumor tissue

    DEFF Research Database (Denmark)

    Gjetting, Torben; Andresen, Thomas Lars; Christensen, Camilla Laulund;

    2011-01-01

    applied in vivo. Large unilaminary vesicles (LUV) with encapsulated nucleic acids designated stabilizedplasmid-lipo-particle (SPLP) have showed promising results in terms of systemic stability and accumulation in tumor tissue due to the enhanced permeability and retention effect (EPR). We have developed...... a simple protocol for the research-scale preparation of SPLPs from commercially available reagents with high amounts of encapsulated plasmid DNA. The SPLPs show properties of promising accumulation in tumor tissue in comparison to other organs when intravenously injected into xenograft tumor-bearing nude...

  5. A simple protocol for preparation of a liposomal vesicle with encapsulated plasmid DNA that mediate high accumulation and reporter gene activity in tumor tissue

    DEFF Research Database (Denmark)

    Gjetting, Torben; Andresen, Thomas Lars; Christensen, Camilla Laulund;

    2011-01-01

    applied in vivo. Large unilaminary vesicles (LUV) with encapsulated nucleic acids designated stabilizedplasmid- lipo-particle (SPLP) have showed promising results in terms of systemic stability and accumulation in tumor tissue due to the enhanced permeability and retention effect (EPR). We have developed...... a simple protocol for the research-scale preparation of SPLPs from commercially available reagents with high amounts of encapsulated plasmid DNA. The SPLPs show properties of promising accumulation in tumor tissue in comparison to other organs when intravenously injected into xenograft tumor-bearing nude...

  6. Toll-Like Receptor 2- and 6-Mediated Stimulation by Macrophage-Activating Lipopeptide 2 Induces Lipopolysaccharide (LPS) Cross Tolerance in Mice, Which Results in Protection from Tumor Necrosis Factor Alpha but in Only Partial Protection from Lethal LPS Doses

    OpenAIRE

    Deiters, Ursula; Gumenscheimer, Marina; Galanos, Chris; Mühlradt, Peter F.

    2003-01-01

    Patients or experimental animals previously exposed to lipopolysaccharide (LPS) become tolerant to further LPS challenge. We investigated the potential of the macrophage-activating lipopeptide 2 (MALP-2) to induce in vivo cross tolerance to tumor necrosis factor alpha (TNF-α) and LPS. MALP-2-induced tolerance could be of practical interest, as MALP-2 proved much less pyrogenic in rabbits than LPS. Whereas LPS signals via Toll-like receptor 4 (TLR4), MALP-2 uses TLR2 and TLR6. LPS-mediated cyt...

  7. Bone tumor

    Science.gov (United States)

    Tumor - bone; Bone cancer; Primary bone tumor; Secondary bone tumor ... The cause of bone tumors is unknown. They often occur in areas of the bone that grow rapidly. Possible causes include: Genetic defects ...

  8. Novel process of intrathymic tumor-immune tolerance through CCR2-mediated recruitment of Sirpα+ dendritic cells: a murine model.

    Directory of Open Access Journals (Sweden)

    Tomohisa Baba

    Full Text Available Immune surveillance system can detect more efficiently secretory tumor-specific antigens, which are superior as a target for cancer immunotherapy. On the contrary, immune tolerance can be induced in the thymus when a tumor antigen is massively secreted into circulation. Thus, the secretion of tumor-specific antigen may have contradictory roles in tumor immunity in a context-dependent manner. However, it remains elusive on the precise cellular mechanism of intrathymic immune tolerance against tumor antigens. We previously demonstrated that a minor thymic conventional dendritic cell (cDC subset, CD8α(-Sirpα(+ cDCs, but not the major subset, CD8α(+Sirpα(- cDCs can selectively capture blood-borne antigens and crucially contribute to the self-tolerance. In the present study, we further demonstrated that Sirpα(+ cDCs can capture a blood-borne antigen leaking inside the interlobular vascular-rich regions (IVRs. Blood-borne antigen selectively captured by Sirpα(+ cDCs can induce antigen-specific Treg generation or negative selection, depending on the immunogenicity of the presented antigen. Furthermore, CCR2 expression by thymic Sirpα(+ cDCs and abundant expression of its ligands, particularly, CCL2 by tumor-bearing mice prompted us to examine the function of thymic Sirpα(+ cDCs in tumor-bearing mice. Interestingly, tumor-bearing mice deposited CCL2 inside IVRs in the thymus. Moreover, tumor formation induced the accumulation of Sirpα(+ cDCs in IVRs under the control of CCR2-CCL2 axis and enhanced their capacity to take up antigens, resulting in the shift from Treg differentiation to negative selection. Finally, intrathymic negative selection similarly ensued in CCR2-competent mice once the tumor-specific antigen was secreted into bloodstream. Thus, we demonstrated that thymic Sirpα(+ cDCs crucially contribute to this novel process of intrathymic tumor immune tolerance.

  9. 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

    OpenAIRE

    WANG, TING-AN; Zhang, Xiao-Dong; GUO, XING-YU; XIAN, SHU-LIN; Lu, Yun-Fei

    2015-01-01

    Glycolysis is the primary method utilized by cancer cells to produce the energy (adenosine triphosphate, ATP) required for cell proliferation. Therefore, inhibition of glycolysis may inhibit tumor growth. We previously found that both 3-bromopyruvate (3-BrPA) and sodium citrate (SCT) can inhibit glycolysis in vitro; however, the underlying inhibitory mechanisms remain unclear. In the present study, we used a human gastric cancer cell line (SGC-7901) and an orthotopic transplantation tumor mod...

  10. Human antibodies targeting cell surface antigens overexpressed by the hormone refractory metastatic prostate cancer cells: ICAM-1 is a tumor antigen that mediates prostate cancer cell invasion

    OpenAIRE

    Conrad, Fraser; Zhu, Xiaodong; Zhang, Xin; Chalkley, Robert J.; Burlingame, Alma L; Marks, James D.; Liu, Bin

    2009-01-01

    Transition from hormone-sensitive to hormone-refractory metastatic tumor types poses a major challenge for prostate cancer treatment. Tumor antigens that are differentially expressed during this transition are likely to play important roles in imparting prostate cancer cells with the ability to grow in a hormone-deprived environment and to metastasize to distal sites such as the bone and thus, are likely targets for therapeutic intervention. To identify those molecules and particularly cell s...

  11. Fish oil administration mediates apoptosis of Walker 256 tumor cells by modulation of p53, Bcl-2, caspase-7 and caspase-3 protein expression

    OpenAIRE

    Borghetti, Gina; Yamaguchi, Adriana Aya; Aikawa, Julia; Yamazaki, Ricardo Key; de Brito, Gleisson Alisson Pereira; Fernandes, Luiz Claudio

    2015-01-01

    Background Several studies have been shown pro-apoptotic effects of fish oil (FO), rich in n-3 polyunsaturated fatty acids (n-3 PUFA) on cancer cells. Nevertheless, few in vivo experiments have provided data of its ability on apoptosis protein expression in tumor tissue. Thus, in this study we investigate the effect of FO supplementation on apoptosis protein expression in Walker 256 tumor bearing rats. Male Wistar rats were randomly assigned to three groups: fed with regular chow (W); fed reg...

  12. tri-n-butyltin hydride-mediated radical reaction of a 2-iodobenzamide: formation of an unexpected carbon-tin bond

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Marcelo T.; Alves, Rosemeire B.; Cesar, Amary [Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil). Dept. de Quimica; Prado, Maria Auxiliadora F.; Alves, Ricardo J.; Queiroga, Carla G. [Federal de Minas Gerais, Belo Horizonte, MG (Brazil). Faculdade de Farmacia. Dept. de Produtos Farmaceuticos]. E-mail: pradora@farmacia.ufmg.br; Santos, Leonardo S. [Universidad de Talca (Chile). Inst. de Quimica de Recursos Naturales; Eberlin, Marcos N. [Universidade Estadual de Campinas, SP (Brazil). Inst. de Quimica

    2007-03-15

    The tri-n-butyltin hydride-mediated reaction of methyl 2,3-di-O-benzyl-4-O-trans-cinnamyl- 6-deoxy-6-(2-iodobenzoylamino)-{alpha}-D-galactopyranoside afforded an unexpected aryltributyltin compound. The structure of this new tetraorganotin(IV) product has been elucidated by {sup 1}H, {sup 13}C NMR spectroscopy, COSY and HMQC experiments and electrospray ionization mass spectrometry (ESI-MS). The formation of this new compound via a radical coupling reaction and a radical addition-elimination process is discussed. (author)

  13. Vaccination with an adenoviral vector encoding the tumor antigen directly linked to invariant chain induces potent CD4(+) T-cell-independent CD8(+) T-cell-mediated tumor control

    DEFF Research Database (Denmark)

    Sorensen, Maria R; Holst, Peter J; Pircher, Hanspeter;

    2009-01-01

    of the vaccine antigen to invariant chain (Ii). To evaluate this strategy we used a mouse model, in which an immunodominant epitope (GP33) of the LCMV glycoprotein (GP) represents the tumor-associated neoantigen. Prophylactic vaccination of C57BL/6 mice with a replication-deficient human adenovirus 5 vector...... vaccination with adenovirus expressing GP alone (Ad-GP), or GP and Ii unlinked (Ad-GP+Ii). Ad-Ii-GP- induced tumor control depended on an improved generation of the tumor-associated neoantigen-specific CD8(+) T-cell response and was independent of CD4(+) T cells. IFN-gamma was shown to be a key player during...

  14. Culture as a mediator of gene-environment interaction: Cultural consonance, childhood adversity, a 2A serotonin receptor polymorphism, and depression in urban Brazil.

    Science.gov (United States)

    Dressler, William W; Balieiro, Mauro C; Ferreira de Araújo, Luiza; Silva, Wilson A; Ernesto Dos Santos, José

    2016-07-01

    Research on gene-environment interaction was facilitated by breakthroughs in molecular biology in the late 20th century, especially in the study of mental health. There is a reliable interaction between candidate genes for depression and childhood adversity in relation to mental health outcomes. The aim of this paper is to explore the role of culture in this process in an urban community in Brazil. The specific cultural factor examined is cultural consonance, or the degree to which individuals are able to successfully incorporate salient cultural models into their own beliefs and behaviors. It was hypothesized that cultural consonance in family life would mediate the interaction of genotype and childhood adversity. In a study of 402 adult Brazilians from diverse socioeconomic backgrounds, conducted from 2011 to 2014, the interaction of reported childhood adversity and a polymorphism in the 2A serotonin receptor was associated with higher depressive symptoms. Further analysis showed that the gene-environment interaction was mediated by cultural consonance in family life, and that these effects were more pronounced in lower social class neighborhoods. The findings reinforce the role of the serotonergic system in the regulation of stress response and learning and memory, and how these processes in turn interact with environmental events and circumstances. Furthermore, these results suggest that gene-environment interaction models should incorporate a wider range of environmental experience and more complex pathways to better understand how genes and the environment combine to influence mental health outcomes.

  15. Culture as a mediator of gene-environment interaction: Cultural consonance, childhood adversity, a 2A serotonin receptor polymorphism, and depression in urban Brazil.

    Science.gov (United States)

    Dressler, William W; Balieiro, Mauro C; Ferreira de Araújo, Luiza; Silva, Wilson A; Ernesto Dos Santos, José

    2016-07-01

    Research on gene-environment interaction was facilitated by breakthroughs in molecular biology in the late 20th century, especially in the study of mental health. There is a reliable interaction between candidate genes for depression and childhood adversity in relation to mental health outcomes. The aim of this paper is to explore the role of culture in this process in an urban community in Brazil. The specific cultural factor examined is cultural consonance, or the degree to which individuals are able to successfully incorporate salient cultural models into their own beliefs and behaviors. It was hypothesized that cultural consonance in family life would mediate the interaction of genotype and childhood adversity. In a study of 402 adult Brazilians from diverse socioeconomic backgrounds, conducted from 2011 to 2014, the interaction of reported childhood adversity and a polymorphism in the 2A serotonin receptor was associated with higher depressive symptoms. Further analysis showed that the gene-environment interaction was mediated by cultural consonance in family life, and that these effects were more pronounced in lower social class neighborhoods. The findings reinforce the role of the serotonergic system in the regulation of stress response and learning and memory, and how these processes in turn interact with environmental events and circumstances. Furthermore, these results suggest that gene-environment interaction models should incorporate a wider range of environmental experience and more complex pathways to better understand how genes and the environment combine to influence mental health outcomes. PMID:27270123

  16. Therapeutic polypeptides based on HBV core 18-27 epitope can induce CD8+ CTL-mediated cytotoxicity in HLA-A2+ human PBMCs

    Institute of Scientific and Technical Information of China (English)

    Tong-Dong Shi; Yu-Zhang Wu; Zheng-Cai Jia; Li-Yun Zou; Wei Zhou

    2004-01-01

    AIM: To explore how to improve the immunogenicity of HBcAg CTL epitope based polypeptides and to trigger an HBV-specific HLA I-restricted CD8+ T cell response in vitro.METHODS: A new panel of mimetic therapeutic peptides based on the immunodominant B cell epitope of HBV PreS218-24 region, the CTL epitope of HBcAg18-27 and the universal T helper epitope of tetanus toxoid (TT) 830-843was designed using computerized molecular design method and synthesized by Merrifield's solid-phase peptide synthesis.Their immunological properties of stimulating activation and proliferation of lymphocytes, of inducing TH1 polarization,CD8+ T cell magnification and HBV-specific CD8+ CTL mediated cytotoxicity were investigatedin vitro using HLAA2+ human peripheral blood mononuclear cells (PBMCs) from healthy donors and chronic hepatitis B patients.RESULTS: Results demonstrated that the therapeutic polypeptides based on immunodominant HBcAg18-27 CTL,PreS2 B- and universal TH epitopes could stimulate the activation and proliferation of lymphocytes, induce specifically and effectively CD8+ T cell expansion and vigorous HBVspecific CTL-mediated cytotoxicity in human PBMCs.CONCLUSION: It indicated that the introduction of immunodominant T helper plus B-epitopes with short and flexible linkers could dramatically improve the immunogenicity of short CTL epitopes in vitro.

  17. hnRNP A1-mediated translational regulation of the G quadruplex-containing RON receptor tyrosine kinase mRNA linked to tumor progression

    Science.gov (United States)

    Pierredon, Sandra; Le Bras, Morgane; Iacovoni, Jason S.; Teulade-Fichou, Marie-Paule; Favre, Gilles; Roché, Henri; Filleron, Thomas; Millevoi, Stefania; Vagner, Stéphan

    2016-01-01

    The expression and role of RNA binding proteins (RBPs) controlling mRNA translation during tumor progression remains largely uncharacterized. Analysis by immunohistochemistry of the expression of hnRNP A1, hnRNPH, RBM9/FOX2, SRSF1/ASF/SF2, SRSF2/SC35, SRSF3/SRp20, SRSF7/9G8 in breast tumors shows that the expression of hnRNP A1, but not the other tested RBPs, is associated with metastatic relapse. Strikingly, hnRNP A1, a nuclear splicing regulator, is also present in the cytoplasm of tumor cells of a subset of patients displaying exceedingly worse prognosis. Expression of a cytoplasmic mutant of hnRNP A1 leads to increased translation of the mRNA encoding the tyrosine kinase receptor RON/MTS1R, known for its function in tumor dissemination, and increases cell migration in vitro. hnRNP A1 directly binds to the 5′ untranslated region of the RON mRNA and activates its translation through G-quadruplex RNA secondary structures. The correlation between hnRNP A1 and RON tumoral expression suggests that these findings hold clinical relevance. PMID:26930004

  18. Targeting Tumor Cells with Anti-CD44 Antibody Triggers Macrophage-Mediated Immune Modulatory Effects in a Cancer Xenograft Model.

    Science.gov (United States)

    Maisel, Daniela; Birzele, Fabian; Voss, Edgar; Nopora, Adam; Bader, Sabine; Friess, Thomas; Goller, Bernhard; Laifenfeld, Daphna; Weigand, Stefan; Runza, Valeria

    2016-01-01

    CD44, a transmembrane receptor reported to be involved in various cellular functions, is overexpressed in several cancer types and supposed to be involved in the initiation, progression and prognosis of these cancers. Since the sequence of events following the blockage of the CD44-HA interaction has not yet been studied in detail, we profiled xenograft tumors by RNA Sequencing to elucidate the mode of action of the anti-CD44 antibody RG7356. Analysis of tumor and host gene-expression profiles led us to the hypothesis that treatment with RG7356 antibody leads to an activation of the immune system. Using cytokine measurements we further show that this activation involves the secretion of chemo-attractants necessary for the recruitment of immune cells (i.e. macrophages) to the tumor site. We finally provide evidence for antibody-dependent cellular phagocytosis (ADCP) of the malignant cells by macrophages. PMID:27463372

  19. Targeting Tumor Cells with Anti-CD44 Antibody Triggers Macrophage-Mediated Immune Modulatory Effects in a Cancer Xenograft Model.

    Directory of Open Access Journals (Sweden)

    Daniela Maisel

    Full Text Available CD44, a transmembrane receptor reported to be involved in various cellular functions, is overexpressed in several cancer types and supposed to be involved in the initiation, progression and prognosis of these cancers. Since the sequence of events following the blockage of the CD44-HA interaction has not yet been studied in detail, we profiled xenograft tumors by RNA Sequencing to elucidate the mode of action of the anti-CD44 antibody RG7356. Analysis of tumor and host gene-expression profiles led us to the hypothesis that treatment with RG7356 antibody leads to an activation of the immune system. Using cytokine measurements we further show that this activation involves the secretion of chemo-attractants necessary for the recruitment of immune cells (i.e. macrophages to the tumor site. We finally provide evidence for antibody-dependent cellular phagocytosis (ADCP of the malignant cells by macrophages.

  20. Androgen-mediated development of irradiation-induced thyroid tumors in rats: dependence on animal age during interval of androgen replacement in castrated males

    International Nuclear Information System (INIS)

    When male Long-Evans rats at age 8 weeks were radiation treated (40 microCi Na131I), thyroid follicular adenomas and carcinomas were observed at age 24 months with a high incidence of 94%. Castration of males prior to irradiation significantly reduced this tumor incidence to 60%. When testosterone (T) was replaced in castrated, irradiated male rats, differentially increased incidences of thyroid tumors occurred. Immediate (age 2-6 mo) or early (age 6-12 mo) T replacement at approximate physiologic levels led to thyroid follicular tumor incidences of 100 and 82%, respectively, whereas intermediate (12-18 mo) or late (18-24 mo) T treatment led to only 70 and 73% incidences, respectively. Continuous T replacement (2-24 mo) in castrated irradiated male rats raised thyroid tumor incidence to 100%. Since elevated thyroid-stimulating hormone (TSH) is a reported requisite for development of radiation-associated thyroid tumors, the effects of T on serum TSH levels were examined. Mean serum TSH values in all irradiated animal groups were significantly elevated above age-matched nonirradiated animals at 6, 12, 18, and 24 months. Serum TSH levels were higher in continuous T-replaced irradiated castrates than in intact, irradiated males, whereas such intact male TSH levels were greater than those for irradiated castrates without T treatment. Interval T replacement in castrated male rats was associated with increased serum TSH levels during the treatment interval and with lowered TSH levels after discontinuation of T treatment, particularly in irradiated rats. However, when irradiated, castrated males received late T replacement (age 18-24 mo), there was no elevation of TSH at the end of the treatment interval. An indirect effect of T via early stimulation of TSH may be partly responsible for the high incidence of irradiation-induced thyroid tumors in rats

  1. The tumor targeted superantigen ABR-217620 selectively engages TRBV7-9 and exploits TCR-pMHC affinity mimicry in mediating T cell cytotoxicity.

    Directory of Open Access Journals (Sweden)

    Gunnar Hedlund

    Full Text Available The T lymphocytes are the most important effector cells in immunotherapy of cancer. The conceptual objective for developing the tumor targeted superantigen (TTS ABR-217620 (naptumomab estafenatox, 5T4Fab-SEA/E-120, now in phase 3 studies for advanced renal cell cancer, was to selectively coat tumor cells with cytotoxic T lymphocytes (CTL target structures functionally similar to natural CTL pMHC target molecules. Here we present data showing that the molecular basis for the anti-tumor activity by ABR-217620 resides in the distinct interaction between the T cell receptor β variable (TRBV 7-9 and the engineered superantigen (Sag SEA/E-120 in the fusion protein bound to the 5T4 antigen on tumor cells. Multimeric but not monomeric ABR-217620 selectively stains TRBV7-9 expressing T lymphocytes from human peripheral blood similar to antigen specific staining of T cells with pMHC tetramers. SEA/E-120 selectively activates TRBV7-9 expressing T lymphocytes resulting in expansion of the subset. ABR-217620 selectively triggers TRBV7-9 expressing cytotoxic T lymphocytes to kill 5T4 positive tumor cells. Furthermore, ABR-217620 activates TRBV7-9 expressing T cell line cells in the presence of cell- and bead-bound 5T4 tumor antigen. Surface plasmon resonance analysis revealed that ABR-217620 binds to 5T4 with high affinity, to TRBV7-9 with low affinity and to MHC class II with very low affinity. The T lymphocyte engagement by ABR-217620 is constituted by displaying high affinity binding to the tumor cells (KD approximately 1 nM and with the mimicry of natural productive immune TCR-pMHC contact using affinities of around 1 µM. This difference in kinetics between the two components of the ABR-217620 fusion protein will bias the binding towards the 5T4 target antigen, efficiently activating T-cells via SEA/E-120 only when presented by the tumor cells.

  2. Superparamagnetic iron oxide nanoparticles mediated 131I-hVEGF siRNA inhibits hepatocellular carcinoma tumor growth in nude mice

    International Nuclear Information System (INIS)

    Hepatocellular carcinoma (HCC) is a primary liver tumor and is the most difficult human malignancy to treat. In this study, we sought to develop an integrative approach in which real-time tumor monitoring, gene therapy, and internal radiotherapy can be performed simultaneously. This was achieved through targeting HCC with superparamagnetic iron oxide nanoparticles (SPIOs) carrying small interfering RNA with radiolabled iodine 131 (131I) against the human vascular endothelial growth factor (hVEGF). hVEGF siRNA was labeled with 131I by the Bolton-Hunter method and conjugated to SilenceMag, a type of SPIOs. 131I-hVEGF siRNA/SilenceMag was then subcutaneously injected into nude mice with HCC tumors exposed to an external magnetic field (EMF). The biodistribution and cytotoxicity of 131I-hVEGF siRNA/SilenceMag was assessed by SPECT (Single-Photon Emission Computed Tomography) and MRI (Magnetic Resonance Imaging) studies and blood kinetics analysis. The body weight and tumor size of nude mice bearing HCC were measured daily for the 4-week duration of the experiment. 131I-hVEGF siRNA/SilenceMag was successfully labeled; with a satisfactory radiochemical purity (>80%) and biological activity in vitro. External application of an EMF successfully attracted and retained more 131I-hVEGF siRNA/SilenceMag in HCC tumors as shown by SPECT, MRI and biodistribution studies. The tumors treated with 131I-hVEGF siRNA/SilenceMag grew nearly 50% slower in the presence of EMF than those without EMF and the control. Immunohistochemical assay confirmed that the tumor targeted by 131I-hVEGF siRNA/SilenceMag guided by an EMF had a lower VEGF protein level compared to that without EMF exposure and the control. EMF-guided 131I-hVEGF siRNA/SilenceMag exhibited an antitumor effect. The synergic therapy of 131I-hVEGF siRNA/SilenceMag might be a promising future treatment option against HCC with the dual functional properties of tumor therapy and imaging

  3. PacCYP707A2 negatively regulates cherry fruit ripening while PacCYP707A1 mediates drought tolerance

    Science.gov (United States)

    Li, Qian; Chen, Pei; Dai, Shengjie; Sun, Yufei; Yuan, Bing; Kai, Wenbin; Pei, Yuelin; He, Suihuan; Liang, Bin; Zhang, Yushu; Leng, Ping

    2015-01-01

    Sweet cherry is a non-climacteric fruit and its ripening is regulated by abscisic acid (ABA) during fruit development. In this study, four cDNAs (PacCYP707A1–4) encoding 8′-hydroxylase, a key enzyme in the oxidative catabolism of ABA, were identified in sweet cherry fruits using tobacco rattle virus-induced gene silencing (VIGS) and particle bombardment approaches. Quantitative real-time PCR confirmed significant down-regulation of target gene transcripts in VIGS-treated cherry fruits. In PacCYP707A2-RNAi-treated fruits, ripening and fruit colouring were promoted relative to control fruits, and both ABA accumulation and PacNCED1 transcript levels were up-regulated by 140%. Silencing of PacCYP707A2 by VIGS significantly altered the transcripts of both ABA-responsive and ripening-related genes, including the ABA metabolism-associated genes NCED and CYP707A, the anthocyanin synthesis genes PacCHS, PacCHI, PacF3H, PacDFR, PacANS, and PacUFGT, the ethylene biosynthesis gene PacACO1, and the transcription factor PacMYBA. The promoter of PacMYBA responded more strongly to PacCYP707A2-RNAi-treated fruits than to PacCYP707A1-RNAi-treated fruits. By contrast, silencing of PacCYP707A1 stimulated a slight increase in fruit colouring and enhanced resistance to dehydration stress compared with control fruits. These results suggest that PacCYP707A2 is a key regulator of ABA catabolism that functions as a negative regulator of fruit ripening, while PacCYP707A1 regulates ABA content in response to dehydration during fruit development. PMID:25956880

  4. PacCYP707A2 negatively regulates cherry fruit ripening while PacCYP707A1 mediates drought tolerance.

    Science.gov (United States)

    Li, Qian; Chen, Pei; Dai, Shengjie; Sun, Yufei; Yuan, Bing; Kai, Wenbin; Pei, Yuelin; He, Suihuan; Liang, Bin; Zhang, Yushu; Leng, Ping

    2015-07-01

    Sweet cherry is a non-climacteric fruit and its ripening is regulated by abscisic acid (ABA) during fruit development. In this study, four cDNAs (PacCYP707A1-4) encoding 8'-hydroxylase, a key enzyme in the oxidative catabolism of ABA, were identified in sweet cherry fruits using tobacco rattle virus-induced gene silencing (VIGS) and particle bombardment approaches. Quantitative real-time PCR confirmed significant down-regulation of target gene transcripts in VIGS-treated cherry fruits. In PacCYP707A2-RNAi-treated fruits, ripening and fruit colouring were promoted relative to control fruits, and both ABA accumulation and PacNCED1 transcript levels were up-regulated by 140%. Silencing of PacCYP707A2 by VIGS significantly altered the transcripts of both ABA-responsive and ripening-related genes, including the ABA metabolism-associated genes NCED and CYP707A, the anthocyanin synthesis genes PacCHS, PacCHI, PacF3H, PacDFR, PacANS, and PacUFGT, the ethylene biosynthesis gene PacACO1, and the transcription factor PacMYBA. The promoter of PacMYBA responded more strongly to PacCYP707A2-RNAi-treated fruits than to PacCYP707A1-RNAi-treated fruits. By contrast, silencing of PacCYP707A1 stimulated a slight increase in fruit colouring and enhanced resistance to dehydration stress compared with control fruits. These results suggest that PacCYP707A2 is a key regulator of ABA catabolism that functions as a negative regulator of fruit ripening, while PacCYP707A1 regulates ABA content in response to dehydration during fruit development. PMID:25956880

  5. Alternagin-C, a disintegrin-like protein from the venom of Bothrops alternatus, modulates a2ß1 integrin-mediated cell adhesion, migration and proliferation

    Directory of Open Access Journals (Sweden)

    Selistre-de-Araujo H.S.

    2005-01-01

    Full Text Available The alpha2ß1 integrin is a major collagen receptor that plays an essential role in the adhesion of normal and tumor cells to the extracellular matrix. Alternagin-C (ALT-C, a disintegrin-like protein purified from the venom of the Brazilian snake Bothrops alternatus, competitively interacts with the alpha2ß1 integrin, thereby inhibiting collagen binding. When immobilized in plate wells, ALT-C supports the adhesion of fibroblasts as well as of human vein endothelial cells (HUVEC and does not detach cells previously bound to collagen I. ALT-C is a strong inducer of HUVEC proliferation in vitro. Gene expression analysis was done using an Affimetrix HU-95A probe array with probe sets of ~10,000 human genes. In human fibroblasts growing on collagen-coated plates, ALT-C up-regulates the expression of several growth factors including vascular endothelial growth factor, as well as some cell cycle control genes. Up-regulation of the vascular endothelial growth factor gene and other growth factors could explain the positive effect on HUVEC proliferation. ALT-C also strongly activates protein kinase B phosphorylation, a signaling event involved in endothelial cell survival and angiogenesis. In human neutrophils, ALT-C has a potent chemotactic effect modulated by the intracellular signaling cascade characteristic of integrin-activated pathways. Thus, ALT-C acts as a survival factor, promoting adhesion, migration and endothelial cell proliferation after binding to alpha2ß1 integrin on the cell surface. The biological activities of ALT-C may be helpful as a therapeutic strategy in tissue regeneration as well as in the design of new therapeutic agents targeting alpha2ß1 integrin.

  6. An Oral Salmonella-Based Vaccine Inhibits Liver Metastases by Promoting Tumor-Specific T-Cell-Mediated Immunity in Celiac and Portal Lymph Nodes: A Preclinical Study.

    Science.gov (United States)

    Vendrell, Alejandrina; Mongini, Claudia; Gravisaco, María José; Canellada, Andrea; Tesone, Agustina Inés; Goin, Juan Carlos; Waldner, Claudia Inés

    2016-01-01

    Primary tumor excision is one of the most widely used therapies of cancer. However, the risk of metastases development still exists following tumor resection. The liver is a common site of metastatic disease for numerous cancers. Breast cancer is one of the most frequent sources of metastases to the liver. The aim of this work was to evaluate the efficacy of the orally administered Salmonella Typhi vaccine strain CVD 915 on the development of liver metastases in a mouse model of breast cancer. To this end, one group of BALB/c mice was orogastrically immunized with CVD 915, while another received PBS as a control. After 24 h, mice were injected with LM3 mammary adenocarcinoma cells into the spleen and subjected to splenectomy. This oral Salmonella-based vaccine produced an antitumor effect, leading to a decrease in the number and volume of liver metastases. Immunization with Salmonella induced an early cellular immune response in mice. This innate stimulation rendered a large production of IFN-γ by intrahepatic immune cells (IHIC) detected within 24 h. An antitumor adaptive immunity was found in the liver and celiac and portal lymph nodes (LDLN) 21 days after oral bacterial inoculation. The antitumor immune response inside the liver was associated with increased CD4(+) and dendritic cell populations as well as with an inflammatory infiltrate located around liver metastatic nodules. Enlarged levels of inflammatory cytokines (IFN-γ and TNF) were also detected in IHIC. Furthermore, a tumor-specific production of IFN-γ and TNF as well as tumor-specific IFN-γ-producing CD8 T cells (CD8(+)IFN-γ(+)) were found in the celiac and portal lymph nodes of Salmonella-treated mice. This study provides first evidence for the involvement of LDLN in the development of an efficient cellular immune response against hepatic tumors, which resulted in the elimination of liver metastases after oral Salmonella-based vaccination.

  7. An oral Salmonella-based vaccine inhibits liver metastases by promoting tumor-specific T cell-mediated immunity in celiac & portal lymph nodes. A preclinical study.

    Directory of Open Access Journals (Sweden)

    Alejandrina eVendrell

    2016-03-01

    Full Text Available Primary tumor excision is one of the therapies of cancer most widely used. However, the risk of metastases development still exists following tumor resection. The liver is a common site of metastatic disease for numerous cancers. Breast cancer is one of the most frequent source of metastases to the liver. The aim of this work was to evaluate the efficacy of the orally-administered Salmonella Typhi vaccine strain CVD 915 on the development of liver metastases in a mouse model of breast cancer. To this end, one group of BALB/c mice was immunized with CVD 915 via o.g. while another received PBS as a control. After 24 h, mice were injected with LM3 mammary adenocarcinoma cells into the spleen and subjected to splenectomy. This oral Salmonella-based vaccine produced an antitumor effect, leading to a decrease in the number and volume of liver metastases. Immunization with Salmonella induced an early cellular immune response in mice. This innate stimulation rendered a large production of IFN-γ by intrahepatic immune cells (IHIC detected within 24 h. An antitumor adaptive immunity was found in the liver and celiac & portal lymph nodes (LDLN 21 days after oral bacterial inoculation. The antitumor immune response inside the liver was associated with increased CD4+ and DC cell populations as well as with an inflammatory infiltrate located around liver metastatic nodules. Enlarged levels of inflammatory cytokines (IFN-γ and TNF were also detected in IHIC. Furthermore, a tumor-specific production of IFN-γ and TNF as well as tumor-specific IFN-γ-producing CD8 T cells (CD8+IFN-γ+ were found in the celiac & portal lymph nodes of Salmonella-treated mice. This study provides first evidence for the involvement of LDLN in the development of an efficient cellular immune response against hepatic tumors, which resulted in the elimination of liver metastases after oral Salmonella-based vaccination.

  8. Smart IR780 Theranostic Nanocarrier for Tumor-Specific Therapy: Hyperthermia-Mediated Bubble-Generating and Folate-Targeted Liposomes.

    Science.gov (United States)

    Guo, Fang; Yu, Meng; Wang, Jinping; Tan, Fengping; Li, Nan

    2015-09-23

    The therapeutic effectiveness of chemotherapy was hampered by dose-limiting toxicity and was optimal only when tumor cells were subjected to a maximum drug exposure. The purpose of this work was to design a dual-functional thermosensitive bubble-generating liposome (BTSL) combined with conjugated targeted ligand (folate, FA) and photothermal agent (IR780), to realize enhanced therapeutic and diagnostic functions. This drug carrier was proposed to target tumor cells owing to FA-specific binding, followed by triggering drug release due to the decomposition of encapsulated ammonium bicarbonate (NH4HCO3) (generated CO2 bubbles) by being subjected to near-infrared (near-IR) laser irradiation, creating permeable defects in the lipid bilayer that rapidly release drug. In vitro temperature-triggered release study indicated the BTSL system was sensitive to heat triggering, resulting in rapid drug release under hyperthermia. For in vitro cellular uptake experiments, different results were observed on human epidermoid carcinoma cells (KB cells) and human lung cancer cells (A549 cells) due to their different (positive or negative) response to FA receptor. Furthermore, in vivo biodistribution analysis and antitumor study indicated IR780-BTSL-FA could specifically target KB tumor cells, exhibiting longer circulation time than free drug. In the pharmacodynamics experiments, IR780-BTSL-FA efficiently inhibited tumor growth in nude mice with no evident side effect to normal tissues and organs. Results of this study demonstrated that the constructed smart theranostic nanocarrier IR780-BTSL-FA might contribute to establishment of tumor-selective and effective chemotherapy. PMID:26322900

  9. Different cellular sources and different roles of adenosine: A1 receptor-mediated inhibition through astrocytic-driven volume transmission and synapse-restricted A2A receptor-mediated facilitation of plasticity

    OpenAIRE

    Cunha, Rodrigo A.

    2008-01-01

    Adenosine is a prototypical neuromodulator, which mainly controls excitatory transmission through the activation of widespread inhibitory A1 receptors and synaptically located A2A receptors. It was long thought that the predominant A1 receptor-meditated modulation by endogenous adenosine was a homeostatic process intrinsic to the synapse. New studies indicate that endogenous extracellular adenosine is originated as a consequence of the release of gliotransmitters, namely ATP, which sets a glo...

  10. MicroRNA-mediated Silencing of RhoC Inhibits Tumor Invasion and Increases Chemosensitivity to Paclitaxel in SKOV3 Cells in vitro

    Institute of Scientific and Technical Information of China (English)

    PAN Ying; DU Zhen-wu; LENG Wei-chun; ZHOU Jia-wen; WANG Ying-jian; SHENG Min-jia; WANG Jun-rong; ZHANG Gui-zhen

    2011-01-01

    RhoC is a member of the Ras-homologous family of genes which are implicated in tumorigenesis and tumor progression. Up-regulation of RhoC is associated with tumor progression in ovarian carcinoma and RhoC is significantly correlated with the invasive capability of ovarian cancer cell lines in vitro. We developed a system that blocks RhoC in the human ovarian cancer SKOV3 cells using specific MicroRNA(miRNA) interference. By transfecting SKOV3 cells with the plasmid vector to express specific MiRNA that targets human RhoC, we were able to establish a stable clone in which RhoC expression was significantly downregnlated. This resulted in the decreased invasive potential of SKOV3 cells as well as increased chemosensitivity to paclitaxel. RhoC involves in invasion and chemosensitivity of SKOV3, indicating that RhoC may be a promising therapeutic target for ovarian cancer.

  11. Enhancing Tumor Cell Response to Chemotherapy through the Targeted Delivery of Platinum Drugs Mediated by Highly Stable, Multifunctional Carboxymethylcellulose-Coated Magnetic Nanoparticles.

    Science.gov (United States)

    Medříková, Zdenka; Novohradsky, Vojtech; Zajac, Juraj; Vrána, Oldřich; Kasparkova, Jana; Bakandritsos, Aristides; Petr, Martin; Zbořil, Radek; Brabec, Viktor

    2016-07-01

    The fabrication of nanoparticles using different formulations, and which can be used for the delivery of chemotherapeutics, has recently attracted considerable attention. We describe herein an innovative approach that may ultimately allow for the selective delivery of anticancer drugs to tumor cells by using an external magnet. A conventional antitumor drug, cisplatin, has been incorporated into new carboxymethylcellulose-stabilized magnetite nanoparticles conjugated with the fluorescent marker Alexa Fluor 488 or folic acid as targeting agent. The magnetic nanocarriers possess exceptionally high biocompatibility and colloidal stability. These cisplatin-loaded nanoparticles overcome the resistance mechanisms typical of free cisplatin. Moreover, experiments aimed at the localization of the nanoparticles driven by an external magnet in a medium that mimics physiological conditions confirmed that this localization can inhibit tumor cell growth site-specifically. PMID:27246144

  12. The Tumor Antigen NY-ESO-1 Mediates Direct Recognition of Melanoma Cells by CD4+ T Cells after Intercellular Antigen Transfer.

    Science.gov (United States)

    Fonteneau, Jean Francois; Brilot, Fabienne; Münz, Christian; Gannagé, Monique

    2016-01-01

    NY-ESO-1-specific CD4(+) T cells are of interest for immune therapy against tumors, because it has been shown that their transfer into a patient with melanoma resulted in tumor regression. Therefore, we investigated how NY-ESO-1 is processed onto MHC class II molecules for direct CD4(+) T cell recognition of melanoma cells. We could rule out proteasome and autophagy-dependent endogenous Ag processing for MHC class II presentation. In contrast, intercellular Ag transfer, followed by classical MHC class II Ag processing via endocytosis, sensitized neighboring melanoma cells for CD4(+) T cell recognition. However, macroautophagy targeting of NY-ESO-1 enhanced MHC class II presentation. Therefore, both elevated NY-ESO-1 release and macroautophagy targeting could improve melanoma cell recognition by CD4(+) T cells and should be explored during immunotherapy of melanoma.

  13. Adenovirus-mediated and tumor-specific transgene expression of the sodium-iodide symporter from the human telomerase reverse transcriptase promoter enhances killing of lung cancer cell line in vitro

    Institute of Scientific and Technical Information of China (English)

    SHI Yi-zhen; ZHANG Jun; LIU Zeng-li; DU Shou-ying; SHEN Yong-mei

    2010-01-01

    Background The sodium-iodide symporter (NIS) protein can mediate the active radioiodine uptake.The human telomerase reverse transcriptase (hTERT) promoter is known to be selectively reactivated in majority of tumors and hence could be used for tumor targeting.We constructed a recombinant adenovirus containing the human sodium iodide symporter (hNIS) gene directed by the hTERT promoter, characterized the ability of infected cells in uptaking iodide, and explored the therapeutic efficacy of 131I in a lung cancer cell line in vitro.Methods The hTERT promoter was amplified by PCR from DNA isolated from log-phase HepG2 cells, subcloned into lineralized FL*-hNIS/pcDNA3, and then the hTERT-hNIS sequence was subcloned into the shuttle plasmid pAdTrack.The recombinant adenovirus Ad-hTERT-hNIS was constructed by AdEasy system.A positive control adenovirusAd-CMV-hNIS and a negative control adenovirus Ad-CMV were created similarly.A549 cells were transduced with recombinant adenoviruses.125I uptake studies and sodium perchlorate suppression studies were used to confirm hNIS expression and function.Toxic effects of 131I on tumor cells were studied by in vitro clonogenic assay.Results We first successfully constructed an adenovirus mediated transgene expression system of the hNIS under the control of hTERT promoter.When infected with recombinant adenovirus constructs expressing hNIS directed by hTERTand CMV-promoters (Ad-hTERT-hNIS and Ad-CMV-hNIS, respectively), the lung cancer cell line A549 had increased ability to uptake radioiodide up to 23- and 30- fold compared to the control parental cells, respectively.The radioiodide uptake ability of both the Ad-CMV-hNIS and Ad-hTERT-hNIS transduced cell lines were repressed 11-fold by sodium perchlorate (NaCIO4).The subsequent in vitro clonogenic assay of the infected A549 cell line was further repressed to 23% (Ad-CMV-hNIS) and 30% (Ad-hTERT-hNIS) of the control group after receiving radioiodide for 7 hours (P <0.001).Conclusion

  14. 5-Azacytidine treatment sensitizes tumor cells to T-cell mediated cytotoxicity and modulates NK cells in patients with myeloid malignancies

    OpenAIRE

    Gang, A O; Frøsig, T M; Brimnes, M K; Lyngaa, R; Treppendahl, M B; Grønbæk, K; Dufva, I H; Straten, P thor; Hadrup, S R

    2014-01-01

    Treatment with the demethylating agent 5-Azacytidine leads to prolonged survival for patients with myelodysplastic syndrome, and the demethylation induces upregulation of cancer-testis antigens. Cancer-testis antigens are well-known targets for immune recognition in cancer, and the immune system may have a role in this treatment regimen. We show here that 5-Azacytidine treatment leads to increased T-cell recognition of tumor cells. T-cell responses against a large panel of cancer-testis antig...

  15. Treatment with 5-Aza-2'-Deoxycytidine Induces Expression of NY-ESO-1 and Facilitates Cytotoxic T Lymphocyte-Mediated Tumor Cell Killing.

    Directory of Open Access Journals (Sweden)

    Agnes S Klar

    Full Text Available NY-ESO-1 belongs to the cancer/testis antigen (CTA family and represents an attractive target for cancer immunotherapy. Its expression is induced in a variety of solid tumors via DNA demethylation of the promoter of CpG islands. However, NY-ESO-1 expression is usually very low or absent in some tumors such as breast cancer or multiple myeloma. Therefore, we established an optimized in vitro treatment protocol for up-regulation of NY-ESO-1 expression by tumor cells using the hypomethylating agent 5-aza-2'-deoxycytidine (DAC.We demonstrated de novo induction of NY-ESO-1 in MCF7 breast cancer cells and significantly increased expression in U266 multiple myeloma cells. This effect was time- and dose-dependent with the highest expression of NY-ESO-1 mRNA achieved by the incubation of 10 μM DAC for 72 hours. NY-ESO-1 activation was also confirmed at the protein level as shown by Western blot, flow cytometry, and immunofluorescence staining. The detection and quantification of single NY-ESO-1 peptides presented at the tumor cell surface in the context of HLA-A*0201 molecules revealed an increase of 100% and 50% for MCF7 and U266 cells, respectively. Moreover, the enhanced expression of NY-ESO-1 derived peptides at the cell surface was accompanied by an increased specific lysis of MCF7 and U266 cells by HLA-A*0201/NY-ESO-1(157-165 peptide specific chimeric antigen receptor (CAR CD8+ T cells. In addition, the killing activity of CAR T cells correlated with the secretion of higher IFN-gamma levels.These results indicate that NY-ESO-1 directed immunotherapy with specific CAR T cells might benefit from concomitant DAC treatment.

  16. Treatment with 5-Aza-2'-Deoxycytidine Induces Expression of NY-ESO-1 and Facilitates Cytotoxic T Lymphocyte-Mediated Tumor Cell Killing

    Science.gov (United States)

    Klar, Agnes S.; Gopinadh, Jakka; Kleber, Sascha; Wadle, Andreas; Renner, Christoph

    2015-01-01

    Background NY-ESO-1 belongs to the cancer/testis antigen (CTA) family and represents an attractive target for cancer immunotherapy. Its expression is induced in a variety of solid tumors via DNA demethylation of the promoter of CpG islands. However, NY-ESO-1 expression is usually very low or absent in some tumors such as breast cancer or multiple myeloma. Therefore, we established an optimized in vitro treatment protocol for up-regulation of NY-ESO-1 expression by tumor cells using the hypomethylating agent 5-aza-2'-deoxycytidine (DAC). Methodology/Principal Findings We demonstrated de novo induction of NY-ESO-1 in MCF7 breast cancer cells and significantly increased expression in U266 multiple myeloma cells. This effect was time- and dose-dependent with the highest expression of NY-ESO-1 mRNA achieved by the incubation of 10 μM DAC for 72 hours. NY-ESO-1 activation was also confirmed at the protein level as shown by Western blot, flow cytometry, and immunofluorescence staining. The detection and quantification of single NY-ESO-1 peptides presented at the tumor cell surface in the context of HLA-A*0201 molecules revealed an increase of 100% and 50% for MCF7 and U266 cells, respectively. Moreover, the enhanced expression of NY-ESO-1 derived peptides at the cell surface was accompanied by an increased specific lysis of MCF7 and U266 cells by HLA-A*0201/NY-ESO-1(157–165) peptide specific chimeric antigen receptor (CAR) CD8+ T cells. In addition, the killing activity of CAR T cells correlated with the secretion of higher IFN-gamma levels. Conclusions/Significance These results indicate that NY-ESO-1 directed immunotherapy with specific CAR T cells might benefit from concomitant DAC treatment. PMID:26447882

  17. Quercetin inhibits angiogenesis mediated human prostate tumor growth by targeting VEGFR- 2 regulated AKT/mTOR/P70S6K signaling pathways.

    Directory of Open Access Journals (Sweden)

    Poyil Pratheeshkumar

    Full Text Available Angiogenesis is a crucial step in the growth and metastasis of cancers, since it enables the growing tumor to receive oxygen and nutrients. Cancer prevention using natural products has become an integral part of cancer control. We studied the antiangiogenic activity of quercetin using ex vivo, in vivo and in vitro models. Rat aortic ring assay showed that quercetin at non-toxic concentrations significantly inhibited microvessel sprouting and exhibited a significant inhibition in the proliferation, migration, invasion and tube formation of endothelial cells, which are key events in the process of angiogenesis. Most importantly, quercetin treatment inhibited ex vivo angiogenesis as revealed by chicken egg chorioallantoic membrane assay (CAM and matrigel plug assay. Western blot analysis showed that quercetin suppressed VEGF induced phosphorylation of VEGF receptor 2 and their downstream protein kinases AKT, mTOR, and ribosomal protein S6 kinase in HUVECs. Quercetin (20 mg/kg/d significantly reduced the volume and the weight of solid tumors in prostate xenograft mouse model, indicating that quercetin inhibited tumorigenesis by targeting angiogenesis. Furthermore, quercetin reduced the cell viability and induced apoptosis in prostate cancer cells, which were correlated with the downregulation of AKT, mTOR and P70S6K expressions. Collectively the findings in the present study suggest that quercetin inhibits tumor growth and angiogenesis by targeting VEGF-R2 regulated AKT/mTOR/P70S6K signaling pathway, and could be used as a potential drug candidate for cancer therapy.

  18. Merlin/NF2 Suppresses Pancreatic Tumor Growth and Metastasis by Attenuating the FOXM1-Mediated Wnt/β-Catenin Signaling.

    Science.gov (United States)

    Quan, Ming; Cui, Jiujie; Xia, Tian; Jia, Zhiliang; Xie, Dacheng; Wei, Daoyan; Huang, Suyun; Huang, Qian; Zheng, Shaojiang; Xie, Keping

    2015-11-15

    Merlin, the protein encoded by the NF2 gene, is a member of the band 4.1 family of cytoskeleton-associated proteins and functions as a tumor suppressor for many types of cancer. However, the roles and mechanism of Merlin expression in pancreatic cancer have remained unclear. In this study, we sought to determine the impact of Merlin expression on pancreatic cancer development and progression using human tissue specimens, cell lines, and animal models. Decreased expression of Merlin was pronounced in human pancreatic tumors and cancer cell lines. Functional analysis revealed that restored expression of Merlin inhibited pancreatic tumor growth and metastasis in vitro and in vivo. Furthermore, Merlin suppressed the expression of Wnt/β-catenin signaling downstream genes and the nuclear expression of β-catenin protein, and overexpression of Forkhead box M1 (FOXM1) attenuated the suppressive effect of Merlin on Wnt/β-catenin signaling. Mechanistically, Merlin decreased the stability of FOXM1 protein, which plays critical roles in nuclear translocation of β-catenin. Collectively, these findings demonstrated that Merlin critically regulated pancreatic cancer pathogenesis by suppressing FOXM1/β-catenin signaling, suggesting that targeting novel Merlin/FOXM1/β-catenin signaling is an effective therapeutic strategy for pancreatic cancer.

  19. Highly active microbial phosphoantigen induces rapid yet sustained MEK/Erk- and PI-3K/Akt-mediated signal transduction in anti-tumor human gammadelta T-cells.

    Directory of Open Access Journals (Sweden)

    Daniel V Correia

    Full Text Available BACKGROUND: The unique responsiveness of Vgamma9Vdelta2 T-cells, the major gammadelta subset of human peripheral blood, to non-peptidic prenyl pyrophosphate antigens constitutes the basis of current gammadelta T-cell-based cancer immunotherapy strategies. However, the molecular mechanisms responsible for phosphoantigen-mediated activation of human gammadelta T-cells remain unclear. In particular, previous reports have described a very slow kinetics of activation of T-cell receptor (TCR-associated signal transduction pathways by isopentenyl pyrophosphate and bromohydrin pyrophosphate, seemingly incompatible with direct binding of these antigens to the Vgamma9Vdelta2 TCR. Here we have studied the most potent natural phosphoantigen yet identified, (E-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (HMB-PP, produced by Eubacteria and Protozoa, and examined its gammadelta T-cell activation and anti-tumor properties. METHODOLOGY/PRINCIPAL FINDINGS: We have performed a comparative study between HMB-PP and the anti-CD3epsilon monoclonal antibody OKT3, used as a reference inducer of bona fide TCR signaling, and followed multiple cellular and molecular gammadelta T-cell activation events. We show that HMB-PP activates MEK/Erk and PI-3K/Akt pathways as rapidly as OKT3, and induces an almost identical transcriptional profile in Vgamma9(+ T-cells. Moreover, MEK/Erk and PI-3K/Akt activities are indispensable for the cellular effects of HMB-PP, including gammadelta T-cell activation, proliferation and anti-tumor cytotoxicity, which are also abolished upon antibody blockade of the Vgamma9(+ TCR Surprisingly, HMB-PP treatment does not induce down-modulation of surface TCR levels, and thereby sustains gammadelta T-cell activation upon re-stimulation. This ultimately translates in potent human gammadelta T-cell anti-tumor function both in vitro and in vivo upon transplantation of human leukemia cells into lymphopenic mice, CONCLUSIONS/SIGNIFICANCE: The development of

  20. Nuclear Factor κB is Required for Tumor Growth Inhibition Mediated by Enavatuzumab (PDL192), a Humanized Monoclonal Antibody to TweakR.

    Science.gov (United States)

    Purcell, James W; Kim, Han K; Tanlimco, Sonia G; Doan, Minhtam; Fox, Melvin; Lambert, Peter; Chao, Debra T; Sho, Mien; Wilson, Keith E; Starling, Gary C; Culp, Patricia A

    2014-01-01

    TweakR is a TNF receptor family member, whose natural ligand is the multifunctional cytokine TWEAK. The growth inhibitory activity observed following TweakR stimulation in certain cancer cell lines and the overexpression of TweakR in many solid tumor types led to the development of enavatuzumab (PDL192), a humanized IgG1 monoclonal antibody to TweakR. The purpose of this study was to determine the mechanism of action of enavatuzumab's tumor growth inhibition and to provide insight into the biology behind TweakR as a cancer therapeutic target. A panel of 105 cancer lines was treated with enavatuzumab in vitro; and 29 cell lines of varying solid tumor backgrounds had >25% growth inhibition in response to the antibody. Treatment of sensitive cell lines with enavatuzumab resulted in the in vitro and in vivo (xenograft) activation of both classical (p50, p65) and non-classical (p52, RelB) NFκB pathways. Using NFκB DNA binding functional ELISAs and microarray analysis, we observed increased activation of NFκB subunits and NFκB-regulated genes in sensitive cells over that observed in resistant cell lines. Inhibiting NFκB subunits (p50, p65, RelB, p52) and upstream kinases (IKK1, IKK2) with siRNA and chemical inhibitors consistently blocked enavatuzumab's activity. Furthermore, enavatuzumab treatment resulted in NFκB-dependent reduction in cell division as seen by the activation of the cell cycle inhibitor p21 both in vitro and in vivo. The finding that NFκB drives the growth inhibitory activity of enavatuzumab suggests that targeting TweakR with enavatuzumab may represent a novel cancer treatment strategy.

  1. Nuclear Factor κB is required for tumor growth inhibition mediated by enavatuzumab (PDL192, a humanized monoclonal antibody to TweakR

    Directory of Open Access Journals (Sweden)

    James W. Purcell

    2014-01-01

    Full Text Available TweakR is a TNF receptor family member, whose natural ligand is the multifunctional cytokine TWEAK. The growth inhibitory activity observed following TweakR stimulation in certain cancer cell lines and the overexpression of TweakR in many solid tumor types led to the development of enavatuzumab (PDL192, a humanized IgG1 monoclonal antibody to TweakR. The purpose of this study was to determine the mechanism of action of enavatuzumab’s tumor growth inhibition and to provide insight into the biology behind TweakR as a cancer therapeutic target. A panel of 105 cancer lines was treated with enavatuzumab in vitro; and 29 cell lines of varying solid tumor backgrounds had >25% growth inhibition in response to the antibody. Treatment of sensitive cell lines with enavatuzumab resulted in the in vitro and in vivo (xenograft activation of both classical (p50, p65 and non-classical (p52, RelB NFκB pathways. Using NFκB DNA binding functional ELISAs and microarray analysis, we observed increased activation of NFκB subunits and NFκB regulated genes in sensitive cells over that observed in resistant cell lines. Inhibiting NFκB subunits (p50, p65, RelB, p52 and upstream kinases (IKK1, IKK2 with siRNA and chemical inhibitors consistently blocked enavatuzumab’s activity. Furthermore, enavatuzumab treatment resulted in NFκB-dependent reduction in cell-division as seen by the activation of the cell cycle inhibitor p21 both in vitro and in vivo. The finding that NFκB drives the growth inhibitory activity of enavatuzumab suggests that targeting TweakR with enavatuzumab may represent a novel cancer treatment strategy.

  2. 2-Methoxyestradiol Exhibits a Biphasic Effect on VEGF-A in Tumor Cells and Upregulation Is Mediated Through ER-α: A Possible Signaling Pathway Associated with the Impact of 2-ME2 on Proliferative Cells

    Directory of Open Access Journals (Sweden)

    Samarendra N. Banerjee

    2003-09-01

    Full Text Available 2-Methoxyestradiol (2-ME2 was reported to elicit both stimulation and inhibition of tumor angiogenesis and growth depending on the dosage used. However, the mechanism(s of the biphasic action of 2-ME2 has been elusive. Here we describe a regulatory role of vascular endothelial growth factor-A (VEGF-A in the biphasic effects on estrogen receptor (ER+ GH3 rat pituitary tumor cells and MCF-7 human breast tumor cells depending on the dosage of 2-ME2 used. We observed that acute exposure to 2-ME2, irrespective of dosage, did not alter cellular proliferation, but enhanced the VEGF-A mRNA level. As the treatment duration increased, biphasic effect was elicited. A concentration of 1 μM 2-ME2 increased both cell proliferation and VEGF-A levels in these cells, whereas higher doses exhibited reversed impact. A low dose of 2-ME2 also increased the VEGF-A mRNA expression in ER-α-transfected human mammary epithelial cells (HMECs. The effect was reversed in ER- cells. The enhanced expression of VEGF-A mRNA could be blocked by the pure estrogen antagonist, ICI 182,780, reveal that the upregulation of VEGF-A expression by 2-ME2 is mediated through ER-α. Furthermore, the biphasic effect of 2-ME2 on cell proliferation can be modulated by administrating VEGF-A antibodies or VEGF-A proteins. Studies also demonstrate that the VEGF-A protein, induced by 2-ME2, is functionally active and upregulates the proliferation of adjacent endothelial cells.

  3. MicroRNA-mediated Tumor Multidrug Resistance and Function of Traditional Chinese Medicine%microRNA介导肿瘤多药耐药及中药的作用

    Institute of Scientific and Technical Information of China (English)

    张瑞娟; 许建华; 余文燕; 王国娟; 孙珏; 范忠泽

    2013-01-01

    MicroRNA (miRNA for short) can induce mRNA cleavage or inhibit mRNA translation and regulate gene expression in the post-transcriptional level, which involves cell development, proliferation, differentiation, apoptosis, and a series of important biological processes. Recent studies have found that the abnormal regulation of miRNA's target genes may be involved in tumor resistance. And it is expected to become important tumor resistance-associat-ed molecular markers and therapeutic targets. Mechanism of traditional Chinese medicine (TCM) and its active ingre-dients can affect miRNA to regulate target proteins and target genes mediated tumor multidrug resistance. It can pro-vide new ideas for the mechanism of reversing multidrug resistance by TCM.%microRNA(简称miRNA)能通过诱导mRNA裂解或抑制mRNA翻译从而在转录后水平调控基因表达,参与细胞发育、增殖、分化、凋亡等一系列重要生物学进程。近期研究发现miRNA对靶基因的异常调控可能参与肿瘤耐药,有望成为重要的肿瘤耐药相关分子标记物及治疗靶点。中药及其有效成分可影响miRNA进而调控相应靶蛋白和靶基因介导肿瘤多药耐药,为中药逆转多药耐药的机制研究提供新思路。

  4. Preparing clinical-grade myeloid dendritic cells by electroporation-mediated transfection of in vitro amplified tumor-derived mRNA and safety testing in stage IV malignant melanoma

    Directory of Open Access Journals (Sweden)

    Allred Jacob B

    2006-08-01

    Full Text Available Abstract Background Dendritic cells (DCs have been used as vaccines in clinical trials of immunotherapy of cancer and other diseases. Nonetheless, progress towards the use of DCs in the clinic has been slow due in part to the absence of standard methods for DC preparation and exposure to disease-associated antigens. Because different ex vivo exposure methods can affect DC phenotype and function differently, we studied whether electroporation-mediated transfection (electrotransfection of myeloid DCs with in vitro expanded RNA isolated from tumor tissue might be feasible as a standard physical method in the preparation of clinical-grade DC vaccines. Methods We prepared immature DCs (IDCs from CD14+ cells isolated from leukapheresis products and extracted total RNA from freshly resected melanoma tissue. We reversely transcribed the RNA while attaching a T7 promoter to the products that we subsequently amplified by PCR. We transcribed the amplified cDNA in vitro and introduced the expanded RNA into IDCs by electroporation followed by DC maturation and cryopreservation. Isolated and expanded mRNA was analyzed for the presence of melanoma-associated tumor antigens gp100, tyrosinase or MART1. To test product safety, we injected five million DCs subcutaneously at three-week intervals for up to four injections into six patients suffering from stage IV malignant melanoma. Results Three preparations contained all three transcripts, one isolate contained tyrosinase and gp100 and one contained none. Electrotransfection of DCs did not affect viability and phenotype of fresh mature DCs. However, post-thaw viability was lower (69 ± 12 percent in comparison to non-electroporated cells (82 ± 12 percent; p = 0.001. No patient exhibited grade 3 or 4 toxicity upon DC injections. Conclusion Standardized preparation of viable clinical-grade DCs transfected with tumor-derived and in vitro amplified mRNA is feasible and their administration is safe.

  5. RNAi-mediated silencing of CD147 inhibits tumor cell proliferation, invasion and increases chemosensitivity to cisplatin in SGC7901 cells in vitro

    Directory of Open Access Journals (Sweden)

    Zhu Chan

    2010-06-01

    Full Text Available Abstract Background CD147 is a widely distributed cell surface glycoprotein that belongs to the Ig superfamily. CD147 has been implicated in numerous physiological and pathological activities. Enriched on the surface of many tumor cells, CD147 promotes tumor growth, invasion, metastasis and angiogenesis and confers resistance to some chemotherapeutic drugs. In this study, we investigated the possible role of CD147 in the progression of gastric cancer. Methods Short hairpin RNA (shRNA expressing vectors targeting CD147 were constructed and transfected into human gastric cancer cells SGC7901 and CD147 expression was monitored by quantitative realtime RT-PCR and Western blot. Cell proliferation, the activities of MMP-2 and MMP-9, the invasive potential and chemosensitivity to cisplatin of SGC7901 cells were determined by MTT, gelatin zymography, Transwell invasion assay and MTT, respectively. Results Down-regulation of CD147 by RNAi approach led to decreased cell proliferation, MMP-2 and MMP-9 activities and invasive potential of SGC7901 cells as well as increased chemosensitivity to cisplatin. Conclusion CD147 involves in proliferation, invasion and chemosensitivity of human gastric cancer cell line SGC7901, indicating that CD147 may be a promising therapeutic target for gastric cancer.

  6. Macrophage and colon tumor cells as targets for a binuclear silver(I) N-heterocyclic carbene complex, an anti-inflammatory and apoptosis mediator.

    Science.gov (United States)

    Iqbal, Muhammad Adnan; Umar, Muhammad Ihtisham; Haque, Rosenani A; Khadeer Ahamed, Mohamed B; Asmawi, Mohd Zaini Bin; Majid, Amin Malik Shah Abdul

    2015-05-01

    Chronic inflammation intensifies the risk for malignant neoplasm, indicating that curbing inflammation could be a valid strategy to prevent or cure cancer. Cancer and inflammation are inter-related diseases and many anti-inflammatory agents are also used in chemotherapy. Earlier, we have reported a series of novel ligands and respective binuclear Ag(I)-NHC complexes (NHC=N-heterocyclic carbene) with potential anticancer activity. In the present study, a newly synthesized salt (II) and respective Ag(I)-NHC complex (III) of comparable molecular framework were prepared for a further detailed study. Preliminarily, II and III were screened against HCT-116 and PC-3 cells, wherein III showed better results than II. Both the compounds showed negligible toxicity against normal CCD-18Co cells. In FAM-FLICA caspase assay, III remarkably induced caspase-3/7 in HCT-116 cells most probably by tumor necrosis factor-alpha (TNF-α) independent intrinsic pathway and significantly inhibited in vitro synthesis of cytokines, interleukin-1 (IL-1) and TNF-α in human macrophages (U937 cells). In a cell-free system, both the compounds inhibited cyclooxygenase (COX) activities, with III being more selective towards COX-2. The results revealed that III has strong antiproliferative property selectively against colorectal tumor cells which could be attributed to its pro-apoptotic and anti-inflammatory abilities. PMID:25699476

  7. Ultraviolet-Mediated Activation of Photo toxins from Peganum Harmala L. Seedlings to Control both Human-and Phyto-Pathogenic Microorganisms and Tumor Cells

    International Nuclear Information System (INIS)

    The medicinal plant Peganum harmala L. (zygophyllaceae) contains a number of Beta-carboline alkaloids, which are photosensitizers to bacteria, yeasts and eukaryotic cells in the presence of sunlight and artificial sources of long-wave UV radiation (365 nm). Ultraviolet irradiation of ten-day old aseptically germinated Peganum harmala inoculated on bacterial and yeast bioassay plates elicits strong phototoxic antimicrobials. Callus as well as crude methanol extracts of in vitro cultures were also investigated for the accumulation of photosensitizers. High performance liquid chromatographic analyses of irradiated and control tissues followed by fluorescent detection at 302 nm revealed the formation of serotonin (5-hydroxytryptamine) in irradiated tissues only. Eluted compounds detected at 330 nm revealed more than ten-fold accumulation of harmine, isoharmine and harmol in irradiated tissues. Moreover, several simple beta-carboline alkaloids were produced through irradiation with UV such as harmalanine and harmalacidine. UV-induced phototoxicity was proven against phyto pathogenic bacteria and human-pathogenic bacteria and yeasts. Photo-induced cytotoxicity was observed from two different toxicity bioassays, which are Artemia saline and potato discs tumor assay. The selective UV-dependent biological activities may imply a pharmacological potential of Peganum harmala in the control of infectious diseases and tumor tissues

  8. Off-the-shelf adenoviral-mediated immunotherapy via bicistronic expression of tumor antigen and iMyD88/CD40 adjuvant.

    Science.gov (United States)

    Kemnade, Jan Ole; Seethammagari, Mamatha; Narayanan, Priya; Levitt, Jonathan M; McCormick, Alison A; Spencer, David M

    2012-07-01

    Recent modest successes in ex vivo dendritic cell (DC) immunotherapy have motivated continued innovation in the area of DC manipulation and activation. Although ex vivo vaccine approaches continue to be proving grounds for new DC manipulation techniques, the intrinsic limits of ex vivo therapy, including high cost, minimal standardization, cumbersome delivery, and poor accessibility, incentivizes the development of vaccines compatible with in vivo DC targeting. We describe here a method to co-deliver both tumor-specific antigen (TSA) and an iMyD88/CD40 adjuvant (iMC), to DCs that combines toll-like receptor (TLR) and CD40 signaling. In this study, we demonstrate that simple TSA delivery via adenoviral vectors results in strong antitumor immunity. Addition of iMC delivered in a separate vector is insufficient to enhance this effect. However, when delivered simultaneously with TSA in a single bicistronic vector (BV), iMC is able to significantly enhance antigen-specific cytotoxic T-cell (CTL) responses and inhibit established tumor growth. This study demonstrates the spatial-temporal importance of concurrent DC activation and TSA presentation. Further, it demonstrates the feasibility of in vivo molecular enhancement of DCs necessary for effective antitumor immune responses.

  9. Clinical Scale Zinc Finger Nuclease-mediated Gene Editing of PD-1 in Tumor Infiltrating Lymphocytes for the Treatment of Metastatic Melanoma

    Science.gov (United States)

    Beane, Joal D; Lee, Gary; Zheng, Zhili; Mendel, Matthew; Abate-Daga, Daniel; Bharathan, Mini; Black, Mary; Gandhi, Nimisha; Yu, Zhiya; Chandran, Smita; Giedlin, Martin; Ando, Dale; Miller, Jeff; Paschon, David; Guschin, Dmitry; Rebar, Edward J; Reik, Andreas; Holmes, Michael C; Gregory, Philip D; Restifo, Nicholas P; Rosenberg, Steven A; Morgan, Richard A; Feldman, Steven A

    2015-01-01

    Programmed cell death-1 (PD-1) is expressed on activated T cells and represents an attractive target for gene-editing of tumor targeted T cells prior to adoptive cell transfer (ACT). We used zinc finger nucleases (ZFNs) directed against the gene encoding human PD-1 (PDCD-1) to gene-edit melanoma tumor infiltrating lymphocytes (TIL). We show that our clinical scale TIL production process yielded efficient modification of the PD-1 gene locus, with an average modification frequency of 74.8% (n = 3, range 69.9–84.1%) of the alleles in a bulk TIL population, which resulted in a 76% reduction in PD-1 surface-expression. Forty to 48% of PD-1 gene-edited cells had biallelic PD-1 modification. Importantly, the PD-1 gene-edited TIL product showed improved in vitro effector function and a significantly increased polyfunctional cytokine profile (TNFα, GM-CSF, and IFNγ) compared to unmodified TIL in two of the three donors tested. In addition, all donor cells displayed an effector memory phenotype and expanded approximately 500–2,000-fold in vitro. Thus, further study to determine the efficiency and safety of adoptive cell transfer using PD-1 gene-edited TIL for the treatment of metastatic melanoma is warranted. PMID:25939491

  10. Blockade of tumor necrosis factor (TNF) receptor type 1-mediated TNF-alpha signaling protected Wistar rats from diet-induced obesity and insulin resistance.

    Science.gov (United States)

    Liang, Huifang; Yin, Bingjiao; Zhang, Hailong; Zhang, Shu; Zeng, Qingling; Wang, Jing; Jiang, Xiaodan; Yuan, Li; Wang, Cong-Yi; Li, Zhuoya

    2008-06-01

    TNF-alpha plays an important role in the pathogenesis of obesity and insulin resistance in which the effect of TNF-alpha signaling via TNF receptor type 1 (TNFR1) largely remains controversial. To delineate the role of TNFR1-mediated TNF-alpha signaling in the pathogenesis of this disorder, a TNFR1 blocking peptide-Fc fusion protein (TNFR1BP-Fc) was used for the present study. Wistar rats were fed a high-fat/high-sucrose (HFS) diet for 16 wk until obesity and insulin resistance developed. In comparison with increased body weight and fat weight, enlarged adipocytes, and hypertriglyceridemia in the obese state, the subsequent 4-wk treatment with TNFR1BP-Fc resulted in significant weight loss characterized by decreased fat pad weight and adipocyte size and reduced plasma triglycerides. Furthermore, obesity-induced insulin resistance, including hyperinsulinemia, elevated C-peptide, higher degree of hyperglycemia after glucose challenge, and less hypoglycemic response to insulin, was markedly improved, and the compensatory hyperplasia and hypertrophy of pancreatic islets were reduced. Interestingly, treatment with TNFR1BP-Fc markedly suppressed systemic TNF-alpha release and its local expression in pancreatic islets and muscle and adipose tissues. In addition, blockage of TNFR1-mediated TNF-alpha signaling in obese rats significantly enhanced tyrosine phosphorylation of insulin receptor substrate 1 (IRS-1) in the muscle and fat tissues. Our results strongly suggest a pivotal role for TNFR1-mediated TNF-alpha signaling in the pathogenesis of obesity and insulin resistance. Thus, TNFR1BP-Fc may be a good candidate for the treatment of this disease. PMID:18339717

  11. Nm23H1 mediates tumor invasion in esophageal squamous cell carcinoma by regulation of CLDN1 through the AKT signaling

    Science.gov (United States)

    Kuo, K-T; Chen, C-L; Chou, T-Y; Yeh, C-T; Lee, W-H; Wang, L-S

    2016-01-01

    Esophageal cancer is a lethal malignancy worldwide. Previously, low expression of metastasis suppressor Nm23H1 and tight junction (TJ) protein claudin-1 (CLDN1) have been known to correlate with poor prognosis in esophageal squamous cell carcinoma (ESCC). However, the molecular interaction between them has not been clarified. In the present study, we first examined the expression of Nm23H1 and CLDN1 in 74 surgical ESCC samples by immunohistochemistry (IHC) to verify their clinicopathologic significance. The biologic effects of Nm23H1 gene silencing or overexpression in ESCC cell lines were then studied by migration and invasion studies, and its regulation on CLDN1 expression was also investigated by western blot analysis. Moreover, the expression of Nm23H1 and CLDN1 at the same invasion front of ESCC tumors was verified by immunofluorescence. The results showed a significantly positive correlation between the expression of Nm23H1 and CLDN1 (γ=0.296, P=0.011) in surgical specimens, especially for the 34 tumors with lymph-node metastasis (γ=0.455, P=0.007). In ESCC cell lines, silencing of Nm23H1 expression markedly enhanced cell invasiveness, accompanied by increased Akt phosphorylation and decreased CLDN1 expression. Conversely, Nm23H1-expressed transfectants exhibited reduced invasiveness, decreased Akt phosphorylation and correspondingly increased CLDN1 expression. Regain of CLDN1 expression in ESCC cells significantly suppressed invasiveness, but did not influence the Akt phosphorylation. Moreover, treating Nm23H1-depleted cells with the AKT inhibitor MK2206 recovered CLDN1 expression, and diminished the invasiveness of ESCC cells. Finally, decreased expressions of both CLDN1 and E-cadherin were observed at the invasive front of the Nm23H1-negative tumors. Overall, our current study documented that reduced Nm23H1 expression activates the AKT signaling pathway, results in diminished CLDN1 expression and potentiates invasiveness of ESCC cells. Enhancement of Nm

  12. Scintiscans and carcinoid tumors

    International Nuclear Information System (INIS)

    The presence of somatostatin receptors on carcinoid tumors mediate imaging of tumor extent and inhibition of tumor's marker secretion and growth. This prospective study aimed to evaluate radiolabelled somatostatin analogues scans in the therapeutical work-up of carcinoids. Twenty-one patients with carcinoids underwent 26 scans with iodine octreotide or indium pentetreotide. The results for tumor and metastase imaging were analysed and compared to those of a short inhibition test of marker secretion and to those of MIBG scan. The sensitivity for imaging the overall 43 tumor sites was 72%. We had no false positive. Unknown tumors were discovered in three patients. The results were slightly better with indium pentetreotide and in metastase imaging. A positive scan did not always preclude responsiveness to the functional effect of octreotide. Results of somatostatin analogue scans were better than those with MBG. The two techniques showed complementary in one patient. Treatment decision making in patients with carcinoid tumors should benefit from functional inhibition test by octreotide as well as from indium pentreotide and MIBG scans. (authors). 21 refs., 2 figs., 1 tab

  13. Tumor vaccines

    International Nuclear Information System (INIS)

    Tumor vaccines have several potential advantages over standard anticancer regiments. They represent highly specific anticancer therapy. Inducing tumor-specific memory T-lymphocytes, they have potential for long-lived antitumor effects. However, clinical trials, in which cancer patients were vaccinated with tumor vaccines, have been so far mainly disappointing. There are many reasons for the inefficiency of tumor vaccines. Most cancer antigens are normal self-molecules to which immune tolerance exists. That is why the population of tumor-specific lymphocytes is represented by a small number of low-affinity T-lymphocytes that induce weak antitumor immune response. Simultaneously, tumors evolve many mechanisms to actively evade immune system, what makes them poorly immunogenic or even tolerogenic. Novel immunotherapeutic strategies are directed toward breaking immune tolerance to tumor antigens, enhancing immunogenicity of tumor vaccines and overcoming mechanisms of tumor escape. There are several approaches, unfortunately, all of them still far away from an ideal tumor vaccine that would reject a tumor. Difficulties in the activation of antitumor immune response by tumor vaccines have led to the development of alternative immunotherapeutic strategies that directly focus on effector mechanisms of immune system (adoptive tumor- specific T-lymphocyte transfer and tumor specific monoclonal antibodies). (author)

  14. Augmented oxygen-mediated transcriptional activation of cytochrome P450 (CYP)1A expression and increased susceptibilities to hyperoxic lung injury in transgenic mice carrying the human CYP1A1 or mouse 1A2 promoter in vivo.

    Science.gov (United States)

    Jiang, Weiwu; Couroucli, Xanthi I; Wang, Lihua; Barrios, Roberto; Moorthy, Bhagavatula

    2011-04-01

    Supplemental oxygen administration is frequently administered to pre-term and term infants having pulmonary insufficiency. However, hyperoxia contributes to the development of bronchopulmonary dysplasia (BPD) in premature infants. Cytochrome P450 (CYP)A enzymes have been implicated in hyperoxic lung injury. In this study, we tested the hypothesis that hyperoxia induces CYP1A1 and 1A2 enzymes by transcriptional activation of the corresponding promoters in vivo, and transgenic mice expressing the human CYP1A1 or the mouse 1A2 promoter would be more susceptible to hyperoxic lung injury than wild type (WT) mice. Adult WT (CD-1) (12week-old) mice, transgenic mice carrying a 10kb human CYP1A1 promoter and the luciferase (luc) reporter gene (CYP1A1-luc), or mice expressing the mouse CYP1A2 promoter (CYP1A2-luc) were maintained in room air or exposed to hyperoxia for 24-72h. Hyperoxia exposure of CYP1A1-luc mice for 24 and 48h resulted in 2.5- and 1.25-fold increases, respectively, in signal intensities, compared to room air controls. By 72h, the induction had declined to control levels. CYP1A2-luc mice also showed enhanced luc expression after 24-48h, albeit to a lesser extent than those expressing the CYP1A1 promoter. Also, these mice showed decreased levels of endogenous CYP1A1 and 1A2 expression after prolonged hyperoxia, and were also more susceptible to lung injury than similarly exposed WT mice, with CYP1A2-luc mice showing the greatest injury. Our results support the hypothesis that hyperoxia induces CYP1A enzymes by transcriptional activation of its corresponding promoters, and that decreased endogenous expression of these enzymes contribute to the increased susceptibilities to hyperoxic lung injury in the transgenic animals. In summary, this is the first report providing direct evidence of hyperoxia-mediated induction of CYP1A1 and CYP1A2 expression in vivo by mechanisms entailing transcriptional activation of the corresponding promoters, a phenomenon that has

  15. Selective reversal of drug resistance in drug-resistant lung adenocarcinoma cells by tumor-specific expression of MDR1 ribozyme gene mediated by retrovirus

    Institute of Scientific and Technical Information of China (English)

    高振强; 高志萍; 刘喜富; 张涛

    1997-01-01

    According to the fact that CEA gene expressed only in lung adenocarcinoma and not in normal lung cells, a retroviral vector (pCEAMR) was constructed which carried the CEA promoter coupled to MDR1 ribozyme gene. pCEAMR was introduced into drug-resistant lung adenocarcinoma cells GAOK with CEA expression and HeLaK without CEA expression; the expression of pCEAMR and drug resistance in the infected cells were analyzed in vitro and in vivo ; pCEAMR expressed only in CEA-producing GAOK cells and not in non-CEA-producing HeLa cells. The drug resistance to doxorubicin (DOX) decreased 91.5% in the infected GAOK cells and did not change in the infected HeLa cells. In nude mice, DOX could obviously inhibit the growth of the infected GAOK tumors, and had no effect on the growth of the infected HeLa cells. These results indicated that MDR1 ribozyme gene regulated by CEA promoter expressed only in human adenocarcinoma cells and reversed their drug resistance selectively. This gene-drug therapy might serve as an effe

  16. 5-Azacytidine treatment sensitizes tumor cells to T-cell mediated cytotoxicity and modulates NK cells in patients with myeloid malignancies.

    Science.gov (United States)

    Gang, A O; Frøsig, T M; Brimnes, M K; Lyngaa, R; Treppendahl, M B; Grønbæk, K; Dufva, I H; Straten, P Thor; Hadrup, S R

    2014-01-01

    Treatment with the demethylating agent 5-Azacytidine leads to prolonged survival for patients with myelodysplastic syndrome, and the demethylation induces upregulation of cancer-testis antigens. Cancer-testis antigens are well-known targets for immune recognition in cancer, and the immune system may have a role in this treatment regimen. We show here that 5-Azacytidine treatment leads to increased T-cell recognition of tumor cells. T-cell responses against a large panel of cancer-testis antigens were detected before treatment, and these responses were further induced upon initiation of treatment. These characteristics point to an ideal combination of 5-Azacytidine and immune therapy to preferentially boost T-cell responses against cancer-testis antigens. To initiate such combination therapy, essential knowledge is required about the general immune modulatory effect of 5-Azacytidine. We therefore examined potential treatment effects on both immune stimulatory (CD8 and CD4 T cells and Natural Killer (NK) cells) and immune inhibitory cell subsets (myeloid-derived suppressor cells and regulatory T cells). We observed a minor decrease and modulation of NK cells, but for all other populations no effects could be detected. Together, these data support a strategy for combining 5-Azacytidine treatment with immune therapy for potential clinical benefit. PMID:24681961

  17. 5-Azacytidine treatment sensitizes tumor cells to T-cell mediated cytotoxicity and modulates NK cells in patients with myeloid malignancies

    Science.gov (United States)

    Gang, A O; Frøsig, T M; Brimnes, M K; Lyngaa, R; Treppendahl, M B; Grønbæk, K; Dufva, I H; Straten, P thor; Hadrup, S R

    2014-01-01

    Treatment with the demethylating agent 5-Azacytidine leads to prolonged survival for patients with myelodysplastic syndrome, and the demethylation induces upregulation of cancer-testis antigens. Cancer-testis antigens are well-known targets for immune recognition in cancer, and the immune system may have a role in this treatment regimen. We show here that 5-Azacytidine treatment leads to increased T-cell recognition of tumor cells. T-cell responses against a large panel of cancer-testis antigens were detected before treatment, and these responses were further induced upon initiation of treatment. These characteristics point to an ideal combination of 5-Azacytidine and immune therapy to preferentially boost T-cell responses against cancer-testis antigens. To initiate such combination therapy, essential knowledge is required about the general immune modulatory effect of 5-Azacytidine. We therefore examined potential treatment effects on both immune stimulatory (CD8 and CD4 T cells and Natural Killer (NK) cells) and immune inhibitory cell subsets (myeloid-derived suppressor cells and regulatory T cells). We observed a minor decrease and modulation of NK cells, but for all other populations no effects could be detected. Together, these data support a strategy for combining 5-Azacytidine treatment with immune therapy for potential clinical benefit. PMID:24681961

  18. Analysis of Subcellular RNA Fractions Revealed a Transcription-Independent Effect of Tumor Necrosis Factor Alpha on Splicing, Mediated by Spt5.

    Science.gov (United States)

    Diamant, Gil; Eisenbaum, Tal; Leshkowitz, Dena; Dikstein, Rivka

    2016-05-01

    The proinflammatory cytokine tumor necrosis factor alpha (TNF-α) modulates the expression of many genes, primarily through activation of NF-κB. Here, we examined the global effects of the elongation factor Spt5 on nascent and mature mRNAs of TNF-α-induced cells using chromatin and cytosolic subcellular fractions. We identified several classes of TNF-α-induced genes controlled at the level of transcription, splicing, and chromatin retention. Spt5 was found to facilitate splicing and chromatin release in genes displaying high induction rates. Further analysis revealed striking effects of TNF-α on the splicing of 25% of expressed genes; the vast majority were not transcriptionally induced. Splicing enhancement of noninduced genes by TNF-α was transient and independent of NF-κB. Investigating the underlying basis, we found that Spt5 is required for the splicing facilitation of the noninduced genes. In line with this, Spt5 interacts with Sm core protein splicing factors. Furthermore, following TNF-α treatment, levels of RNA polymerase II (Pol II) but not Spt5 are reduced from the splicing-induced genes, suggesting that these genes become enriched with a Pol II-Spt5 form. Our findings revealed the Pol II-Spt5 complex as a highly competent coordinator of cotranscriptional splicing.

  19. A Novel Chimeric Antigen Receptor Against Prostate Stem Cell Antigen Mediates Tumor Destruction in a Humanized Mouse Model of Pancreatic Cancer

    Science.gov (United States)

    Lagisetty, Kiran H.; Tran, Eric; Zheng, Zhili; Gattinoni, Luca; Yu, Zhiya; Burns, William R.; Miermont, Anne M.; Teper, Yaroslav; Rudloff, Udo; Restifo, Nicholas P.; Feldman, Steven A.; Rosenberg, Steven A.; Morgan, Richard A.

    2014-01-01

    Abstract Despite advances in the understanding of its molecular pathophysiology, pancreatic cancer remains largely incurable, highlighting the need for novel therapies. We developed a chimeric antigen receptor (CAR) specific for prostate stem cell antigen (PSCA), a glycoprotein that is overexpressed in pancreatic cancer starting at early stages of malignant transformation. To optimize the CAR design, we used antigen-recognition domains derived from mouse or human antibodies, and intracellular signaling domains containing one or two T cell costimulatory elements, in addition to CD3zeta. Comparing multiple constructs established that the CAR based on human monoclonal antibody Ha1-4.117 had the greatest reactivity in vitro. To further analyze this CAR, we developed a human pancreatic cancer xenograft model and adoptively transferred CAR-engineered T cells into animals with established tumors. CAR-engineered human lymphocytes induced significant antitumor activity, and unlike what has been described for other CARs, a second-generation CAR (containing CD28 cosignaling domain) induced a more potent antitumor effect than a third-generation CAR (containing CD28 and 41BB cosignaling domains). While our results provide evidence to support PSCA as a target antigen for CAR-based immunotherapy of pancreatic cancer, the expression of PSCA on selected normal tissues could be a source of limiting toxicity. PMID:24694017

  20. Brain Tumors

    Science.gov (United States)

    A brain tumor is a growth of abnormal cells in the tissues of the brain. Brain tumors can be benign, with no cancer cells, ... cancer cells that grow quickly. Some are primary brain tumors, which start in the brain. Others are ...

  1. Urogenital tumors

    Energy Technology Data Exchange (ETDEWEB)

    Weller, R.E.

    1994-03-01

    An overview is provided for veterinary care of urogenital tumors in companion animals, especially the dog. Neoplasms discussed include tumors of the kidney, urinary bladder, prostate, testis, ovary, vagina, vulva and the canine transmissible venereal tumor. Topics addressed include description, diagnosis and treatment.

  2. Odontogenic Tumors

    OpenAIRE

    TAHSİNOĞLU, Melih

    2013-01-01

    DefinitionThe neoplasms that consist of the cells considered specialized for odontogenesis, and their product (dentin, enamel, cementum) are called odontogenic tumors.ClassificationTo initiate odontogenesis, epithelium is a must. Same rule holds for the odontogenic tumors: without odontogenic epithelium, odontogenic tumors cannot be, without the induction of odontogenic epithelium odontogenic mesenchyme cannot develop.

  3. Tumor Markers

    Science.gov (United States)

    ... guidelines on a variety of topics, including tumor markers for breast cancer, colorectal cancer, lung cancer, and others. The ... of recurrence 70-Gene signature (Mammaprint®) Cancer type: Breast ... Can tumor markers be used in cancer screening? Because tumor markers ...

  4. Effects of holothurian glycosaminoglycan on coagulation process mediated by tumor cells%海参粘多糖对肿瘤细胞介导的凝血过程的影响

    Institute of Scientific and Technical Information of China (English)

    赵杨; 王生; 陶丽; 王爱云; 陈文星; 郑仕中; 陆茵

    2012-01-01

    Aim To investigate the effects of holothu-rian glycosaminoglycan (hGAG) on the coagulation process mediated by MDA-MB-231 breast cancer cells and its possible mechanisms. Methods MDA-MB-231 breast cancer cells were used as models, the effect of tumor cells treated with different concentrations of hGAG on the plasma recalcification time was observed. Coagulation factor Xa (Fxa) generation was examined with chromogenic substrate S-2222. The changes of Ca + labeled with fluorescent probe Fluo-4/AM were measured by fluorescence plate reader. Flow cytometry was used to detect tissue factor (TF) on the surface of tumor cells. Real-time PCR and western blot were used to measure the mRNA and protein expression of TF, respectively. AKT, MAPK, NF-kB and other signalingpathways were also examined after treated with hGAG. Results hGAG at concentrations of 0. 01μmol·L-1 ~ 1μmol·L-1 extended the plasma recalcification times mediated by tumor cells in a dose dependent manner and decreased the Fxa generation but had no obvious effect on Ca2+ changes. hGAG decreased the mRNA and protein expression of TF, and reduced the phosphorylation of p38 rather than other signaling pathways. Conclusions hGAG inhibits the coagulation process mediated by MDA-MB-231 breast cancer cells through downregulating the expression of TF and phosphorylation of p38.%目的 探究海参粘多糖(hGAG)对MDA-MB-231乳腺癌细胞介导的凝血过程的影响及其作用机制.方法 采用MDA-MB-231乳腺癌细胞为模型,观察经不同浓度的hGAG处理后的肿瘤细胞对血浆复钙时间的影响;采用S-2222发光底物检测凝血因子Xa(FXa)的生成;以Fluo-4/AM为荧光探针,在荧光酶标仪下检测细胞Ca2+的变化;流式细胞仪检测细胞表面组织因子(TF),采用real-time PCR和Western blot的方法分别对TF的mRNA和蛋白水平进行测定;并观察hGAG对AKT、MAPK、NF-κB等信号通路的影响.结果 hGAG 0.01~1 μmol·L-1可以呈剂量依赖性的方式延长

  5. Relationship Between Tumor Markers, ER/PR, HER2, Ki67 and CyclinA2 and Clinical Efficacy of Neoadjuvant Chemotherapy%乳腺癌新辅助化疗疗效及ER/PR,HER2,Ki67,CyclinA2的化疗预测作用

    Institute of Scientific and Technical Information of China (English)

    肖宇; 李惠平; 雷玉涛; 赵红梅; 修典荣; 王晶; 王墨培; 张淑兰; 张照辉

    2011-01-01

    Objective To explore the efficacy of neoadjuvant chemotherapy for breast cancer and predictive value of ER/PR, HER2,Ki67, and CyclinA2 in women with local advanced breast cancer (LABC).Methods From October 2004 to December 2009, 50 patients with stage Ⅰ - Ⅲ primary breast cancer received 2 - 6 cycles of neoadjuvant chemotherapy with anthracycline (EC/FEC) or taxanes-based (TP/TC or TE/PE/TEC) in our hospital.Forty-five of them were followed by definitive surgery and adjuvant chemotherapy.Estrogen receptor (ER)/progesterone receptor (PR) (50 cases), HER2 (48 cases), Ki67 (26 cases) and CyclinA2 (18 cases) were examined with immunohistochemistry before the neoadjuvant chemotherapy.Clinical responds, tumor lessen ratio, and toxicity of the treatment were estimated by ultrasonography and palpation afterwards.Results The medium maximum diameter of the tumors was 3.6 cm before neoadjuvant chemotherapy, and 2.2 cm after the treatment, no significant changes were observed (Z = - 5.723, P = 0.000).The clinical response rate was 76.0% (38/50) in the patients [6% (3/50) CR and 70% (35/50) PR], and SD was 22% (11/50) , PD 2.0% (1/50).In the 45 patients who underwent surgery, pCR was found in 3 cases (3/45, 6.7% ), and tpCR in 3 (3/45, 6.7% ).The 4-year disease-free survival (DFS) rate was 86.2% , and total survival rate was 93.1% [medium DFS 62.4 months, SE: 2.535, 95% CI ( 57.450 - 67.388 )].No significant difference was observed in tumor lessen ratio between pre-menopause and post-menopause patients (46.4% vs.40.6% , P = 0.536) , patients with positive and negative hormone receptors (43.0% vs.42.2% , P = 0.929), patients with positive and negative HER2 (41.3% vs.43.9% , P = 0.774), Ki67 (47.2% vs.43.1%, P=0.363), and CyclinA2 (34.3% vs.50.0%, P=0.375),or among those with high, moderate or low differentiation (44.1% , 42.9% , and 41.3%; P = 0.983 ) or different chemotherapy regimen ( TP/TC 52.7% , TE/PE/TEC 39.8% , and EC

  6. Mangrove dolabrane-type of diterpenes tagalsins suppresses tumor growth via ROS-mediated apoptosis and ATM/ATR-Chk1/Chk2-regulated cell cycle arrest.

    Science.gov (United States)

    Neumann, Jennifer; Yang, Yi; Köhler, Rebecca; Giaisi, Marco; Witzens-Harig, Mathias; Liu, Dong; Krammer, Peter H; Lin, Wenhan; Li-Weber, Min

    2015-12-01

    Natural compounds are an important source for drug development. With an increasing cancer rate worldwide there is an urgent quest for new anti-cancer drugs. In this study, we show that a group of dolabrane-type of diterpenes, collectively named tagalsins, isolated from the Chinese mangrove genus Ceriops has potent cytotoxicity on a panel of hematologic cancer cells. Investigation of the molecular mechanisms by which tagalsins kill malignant cells revealed that it induces a ROS-mediated damage of DNA. This event leads to apoptosis induction and blockage of cell cycle progression at S-G2 phase via activation of the ATM/ATR-Chk1/Chk2 check point pathway. We further show that tagalsins suppress growth of human T-cell leukemia xenografts in vivo. Tagalsins show only minor toxicity on healthy cells and are well tolerated by mice. Our study shows a therapeutic potential of tagalsins for the treatment of hematologic malignancies and a new source of anticancer drugs. PMID:26061604

  7. ADENOVIRUS-MEDIATED EXPRESSION OF PEX, A NONCATALYTIC FRAGMENT OF MATRIX METALLOPROTEINASE-2, AND IT'S INHIBITION ON ANGIOGENESIS AND TUMOR GROWTH

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Objective: To develop an adenovirus system to deliver biologically active peptides or proteins such as angiogenesis inhibitors in vivo for the treatment of cancer. Methods: DNA recombination techniques were employed to construct adenovirus shuttle vector, in which angiogenesis inhibitor was put downstream of rat growth hormone signal peptide, and the C-terminal was the myc-epitope 10-amino-acid peptide for the following up of the protein. Adenovirus was made using the bacteria recombination method. We tested this system using an angiogenesis inhibitor chick MMP-2 C-terminal hemopexin-like fragment (PEX) in Sarcoma 180 (S-180) bearing Kunming mice. The anti-angiogenic effect was performed by chick chorioallantoic membrane assay. Results: PEX was readily secreted outside human stomach carcinoma BGC823 cells as demonstrated by immunofluorescent staining and western blot infected by adenovirus with rat growth hormone signal peptide (E-T-rGH-PEX). However, without signal peptide (E-T-PEX), PEX was expressed and localized in the cytoplasm of the infected cells, and formed large aggregates, which suggested that PEX was insoluble. The adenovirus E-T-rGH-PEX could inhibit angiogenesis, while E-T-rGH-PEX not. The adenoviruses of E-T-rGH-PEX inhibited the growth of S-180 tumor significantly compared with the empty virus control group E-T (P=0.026) and without signal peptide group E-T-PEX (P=0.006) respectively, while E-T-PEX had little effect. Conclusion: These results suggest that this adenoviral system is likely to be used in the gene therapy of cancer to deliver angiogenesis inhibitors.

  8. Chitinase 3-Like 1 (Chil1) Regulates Survival and Macrophage-Mediated Interleukin-1β and Tumor Necrosis Factor Alpha during Pseudomonas aeruginosa Pneumonia.

    Science.gov (United States)

    Marion, Chad R; Wang, Jianmiao; Sharma, Lokesh; Losier, Ashley; Lui, Wei; Andrews, Nathaniel; Elias, Jack A; Kazmierczak, Barbara I; Roy, Craig R; Dela Cruz, Charles S

    2016-07-01

    Pseudomonas aeruginosa causes hospital-acquired pneumonia and is associated with high mortality. An effective response to such an infection includes efficient clearance of pathogenic organisms while limiting collateral damage from the host inflammatory response, known as host resistance and host tolerance, respectively. P. aeruginosa expresses a type III secretion system (T3SS) needle complex that induces NLRC4 (NOD-like receptor C4) activation, interleukin-1β (IL-1β) production, and host tissue damage. Chitinase 3-like-1 (Chil1) is expressed during infection and binds to its receptor, IL-13 receptor α2 (IL-13Rα2), to regulate the pathogen-host response during Streptococcus pneumoniae infection, but the role Chil1 plays in balancing the host resistance and host tolerance during P. aeruginosa pneumonia is not known. We conducted experiments using C57BL/6 mice with or without a genetic deficiency of Chil1 and demonstrated that Chil1-deficient mice succumb to P. aeruginosa infection more rapidly than the wild type (WT). The decreased survival time in infected Chil1-deficient mice is associated with more neutrophils recruited to the airways, more lung parenchymal damage, and increased pulmonary consolidation while maintaining equivalent bacterial killing compared to WT mice. Infected Chil1-deficient mice and bone marrow-derived macrophages (BMDMs) from Chil1-deficient mice have increased production of tumor necrosis factor alpha (TNF-α) and IL-1β compared to infected WT mice and macrophages. Infection of Chil1-deficient BMDMs with non-NLRC4-triggering P. aeruginosa, which is deficient in the T3SS needle complex, did not alter the excessive IL-1β production compared to BMDMs from WT mice. The addition of recombinant Chil1 decreases the excessive IL-1β production but only partially rescues stimulated BMDMs from IL-13Rα2-deficient mice. Our data provide mechanistic insights into how Chil1 regulates P. aeruginosa-induced host responses. PMID:27141083

  9. Co-targeting hexokinase 2-mediated Warburg effect and ULK1-dependent autophagy suppresses tumor growth of PTEN- and TP53-deficiency-driven castration-resistant prostate cancer

    Directory of Open Access Journals (Sweden)

    Lei Wang

    2016-05-01

    Full Text Available Currently, no therapeutic options exist for castration-resistant prostate cancer (CRPC patients who have developed resistance to the second generation anti-androgen receptor (AR axis therapy. Here we report that co-deletion of Pten and p53 in murine prostate epithelium, often observed in human CRPC, leads to AR-independent CRPC and thus confers de novo resistance to second generation androgen deprivation therapy (ADT in multiple independent yet complementary preclinical mouse models. In contrast, mechanism-driven co-targeting hexokinase 2 (HK2-mediated Warburg effect with 2-deoxyglucose (2-DG and ULK1-dependent autophagy with chloroquine (CQ selectively kills cancer cells through intrinsic apoptosis to cause tumor regression in xenograft, leads to a near-complete tumor suppression and remarkably extends survival in Pten−/p53-deficiency-driven CRPC mouse model. Mechanistically, 2-DG causes AMPK phosphorylation, which in turn inhibits mTORC1-S6K1 translation signaling to preferentially block anti-apoptotic protein MCL-l synthesis to prime mitochondria-dependent apoptosis while simultaneously activates ULK1-driven autophagy for cell survival to counteract the apoptotic action of anti-Warburg effect. Accordingly, inhibition of autophagy with CQ sensitizes cancer cells to apoptosis upon 2-DG challenge. Given that 2-DG is recommended for phase II clinical trials for prostate cancer and CQ has been clinically used as an anti-malaria drug for many decades, the preclinical results from our proof-of-principle studies in vivo are imminently translatable to clinical trials to evaluate the therapeutic efficacy by the combination modality for a subset of currently incurable CRPC harboring PTEN and TP53 mutations.

  10. 肿瘤细胞回文序列介导的基因扩增机制研究进展%Research progress on the mechanism of gene amplification mediated by palindromes in tumor genome

    Institute of Scientific and Technical Information of China (English)

    刘佳玮; 徐晖; 张海员; 白静; 傅松滨; 周春水

    2014-01-01

    基因组不稳定是肿瘤细胞的特征性标志,基因扩增是一种特殊的基因组不稳定性的表现形式,其在激活原癌基因引发癌症的过程中起着重要的作用.基因扩增将导致细胞加速生长增殖或耐药生长等表型.人们已经广泛注意到其在癌症的诊断和治疗等方面的重要临床意义.但是,人们对基因扩增的分子机制的认识仍然十分有限,本文综述了回文序列介导的基因扩增的分子机制,提出在DNA断点处以无模板形式、新合成小回文序列可能是一部分肿瘤细胞中基因扩增的关键机制,为进一步探索基因扩增的分子机制提供理论参考.%Gene amplification is a common chromosomal aberration which is often the result of tumor genome instability,and plays a crucial role in the process of activating oncogenes and leading to cancers.As gene amplification often is evident in advanced stages of cancer,its clinical importance in diagnosis and treatment has been popularly recognized.However,the underlying mechanisms governing gene amplification are still not fully understood.Herein,we reviewed one of the well-defined gene amplification mechanisms:DNA double-strand breaks-triggered,palindromes or short DNA inverted repeatsmediated gene amplification model,which was established and validated in a variety of research organisms including T.thermophila,fission yeast,budding yeast and rodent cells.Based on the recent published reports,we put forward a new model for the palindromes mediated gene amplification mechanism,that is de novo synthesis of small palindromic sequences (usually several hundred base pairs in length or shorter) at the DNA breakpoints in a template-free manner is the key determinant for gene amplification in certain tumor genomes.Elucidating the potential mechanism and involved enzymes for the regulation and creation of novel palindromic sequences should shed more light onto the palindromes mediated gene amplification and the

  11. Tumor necrosis factor-mediated inhibition of interleukin-18 in the brain: a clinical and experimental study in head-injured patients and in a murine model of closed head injury.

    Directory of Open Access Journals (Sweden)

    Shohami Esther

    2004-07-01

    Full Text Available Abstract Tumor necrosis factor (TNF and interleukin-(IL-18 are important mediators of neuroinflammation after closed head injury (CHI. Both mediators have been previously found to be significantly elevated in the intracranial compartment after brain injury, both in patients as well as in experimental model systems. However, the interrelation and regulation of these crucial cytokines within the injured brain has not yet been investigated. The present study was designed to assess a potential regulation of intracranial IL-18 levels by TNF based on a clinical study in head-injured patients and an experimental model in mice. In the first part, we investigated the interrelationship between the daily TNF and IL-18 cerebrospinal fluid levels in 10 patients with severe CHI for up to 14 days after trauma. In the second part of the study, the potential TNF-dependent regulation of intracerebral IL-18 levels was further characterized in an experimental set-up in mice: (1 in a standardized model of CHI in TNF/lymphotoxin-α gene-deficient mice and wild-type (WT littermates, and (2 by intracerebro-ventricular injection of mouse recombinant TNF in WT C57BL/6 mice. The results demonstrate an inverse correlation of intrathecal TNF and IL-18 levels in head-injured patients and a TNF-dependent inhibition of IL-18 after intracerebral injection in mice. These findings imply a potential new anti-inflammatory mechanism of TNF by attenuation of IL-18, thus confirming the proposed "dual" function of this cytokine in the pathophysiology of traumatic brain injury.

  12. Integrin Trafficking and Tumor Progression

    Directory of Open Access Journals (Sweden)

    Sejeong Shin

    2012-01-01

    Full Text Available Integrins are major mediators of cancer cell adhesion to extracellular matrix. Through this interaction, integrins play critical roles in cell migration, invasion, metastasis, and resistance to apoptosis during tumor progression. Recent studies highlight the importance of integrin trafficking, endocytosis and recycling, for the functions of integrins in cancer cells. Understanding the molecular mechanisms of integrin trafficking is pivotal for understanding tumor progression and for the development of anticancer drugs.

  13. Low-molecular-weight fractions of Alcalase hydrolyzed egg ovomucin extract exert anti-inflammatory activity in human dermal fibroblasts through the inhibition of tumor necrosis factor-mediated nuclear factor κB pathway.

    Science.gov (United States)

    Sun, Xiaohong; Chakrabarti, Subhadeep; Fang, Jun; Yin, Yulong; Wu, Jianping

    2016-07-01

    Ovomucin is a mucin-like protein from egg white with a variety of biological functions. We hypothesized that ovomucin-derived peptides might exert anti-inflammatory activity. The specific objectives were to test the anti-inflammatory activities of different ovomucin hydrolysates and its various fractions in human dermal fibroblasts, and to understand the possible molecular mechanisms. Three ovomucin hydrolysates were prepared and desalted; only the desalted Alcalase hydrolysate showed anti-inflammatory activity. Desalting of ovomucin hydrolysate enriched the proportion of low-molecular-weight (MW) peptides. Indeed, ultrafiltration of this hydrolysate displayed comparable anti-inflammatory activity in dermal fibroblasts, indicating the responsible role of low-MW bioactive peptides in exerting the beneficial biological function. The anti-inflammatory activity of low-MW peptides was regulated through the inhibition of tumor necrosis factor-mediated nuclear factor κ-light-chain-enhancer of activated B cells activity. Our study demonstrated that both peptide composition and MW distribution play important roles in anti-inflammatory activity. The low-MW fractions prepared from ovomucin Alcalase hydrolysate may have potential applications for maintenance of dermal health and treatment of skin diseases. PMID:27333955

  14. Down-regulation of the Tumor Suppressor C-terminal Src Kinase (Csk)-binding Protein (Cbp)/PAG1 Is Mediated by Epigenetic Histone Modifications via the Mitogen-activated Protein Kinase (MAPK)/Phosphatidylinositol 3-Kinase (PI3K) Pathway*

    OpenAIRE

    Suzuki, Kei; Oneyama, Chitose; Kimura, Hironobu; Tajima, Shoji; Okada, Masato

    2011-01-01

    The transmembrane adaptor protein Cbp (or PAG1) functions as a suppressor of Src-mediated tumor progression by promoting the inactivation of Src. The expression of Cbp is down-regulated in Src-transformed cells and in various human cancer cells, suggesting a potential role for Cbp as a tumor suppressor. However, the mechanisms underlying the down-regulation of Cbp remain unknown. The present study shows that Cbp expression is down-regulated by epigenetic histone modifications via the MAPK/PI3...

  15. Liposome-mediated delivery of the p21 activated kinase-1 (PAK-1) inhibitor IPA-3 limits prostate tumor growth in vivo.

    Science.gov (United States)

    Al-Azayzih, Ahmad; Missaoui, Wided N; Cummings, Brian S; Somanath, Payaningal R

    2016-07-01

    P21 activated kinases-1 (PAK-1) is implicated in various diseases. It is inhibited by the small molecule 'inhibitor targeting PAK1 activation-3' (IPA-3), which is highly specific but metabolically unstable. To address this limitation we encapsulated IPA-3 in sterically stabilized liposomes (SSL). SSL-IPA-3 averaged 139nm in diameter, polydispersity index (PDI) of 0.05, and a zeta potential of -28.1, neither of which changed over 14days; however, the PDI increased to 0.139. Analysis of liposomal IPA-3 levels demonstrated good stability, with 70% of IPA-3 remaining after 7days. SSL-IPA-3 inhibited prostate cancer cell growth in vitro with comparable efficacy to free IPA-3. Excitingly, only a 2day/week dose of SSL-IPA-3 was needed to inhibit the growth of prostate xenografts in vivo, while a similar dose of free IPA-3 was ineffective. These data demonstrate the development and clinical utility of a novel liposomal formulation for the treatment of prostate cancer.

  16. Preliminary Study on the Anti-tumor Effect of HLA-A2 .1 Restricted Survivin-△Ex3 -derived CTL Epitope Gene Vaccine%Survivin-△Ex3蛋白HLA-A2.1限制性CTL表位的基因疫苗抗肿瘤效果初探

    Institute of Scientific and Technical Information of China (English)

    陈英利; 葛存兴; 刘思岐; 张婷婷; 隋广宇; 曹明月; 常亚娟; 刘欣宇

    2014-01-01

    To predict and synthesize HLA-A2.1 restricted survivin-△Ex3-derived CTL epitope gene vaccine,and discuss the protective effects of oral attenuated salmonella vaccine with epitope gene on the model mice of transplanted hepatic cellular cancer. Epitope gene sequences with highest scores in prediction were connected to establish eukaryotic expression vector of pVAX1 -STEs-EGFP,which was then transferred into the attenuated salmonella to act as oral vaccine.Experimental animals were divided into the control group (un-vaccinated),oral salmonella group ,oral attenuated salmonella group (transfected by pVAX1 plasmid),oral atten-uated salmonella group (transfected by pVAX1 -Survivin -△3 (T34A)-EGFP plasmid)and oral attenuated salmonella group (transfected by pVAX1 -STEs-EGFP plasmid).The mice were given immunization and then injected liver cancer cells subcutane-ously.The size of the mass at the injection site was measured.In 5 groups of the mice,the average diameters of the tumor were respec-tively 15.11 ±2.43 mm,13.70 ±2.97 mm,13.05 ±1.77 mm,7.46 ±2.61 mm and 9.05 ±2.18 mm;Epitope gene vaccine groups have significant difference when compared with the other groups (P<0.01 ).We concluded that HLA-A2.1 restricted surviving-△Ex3-derived CTL epitope gene vaccine can inhibit the proliferation and migration of mice liver cancer cells after oral administration to mice.%预测并合成survivin-△Ex3 HLA-A2.1限制性CTL表位的基因疫苗,探讨携带表位基因的减毒鼠伤寒沙门氏菌口服疫苗对小鼠移植肝癌模型的保护作用。将表位基因序列连接,构建pVAX1-STEs-EGFP真核表达载体,转化入减毒鼠伤寒沙门氏菌作为口服疫苗。实验动物分为未免疫对照组、口服沙门氏菌组、pVAX1质粒转染的减毒鼠伤寒沙门氏菌组;口服pVAX1-Survivin-△3(T34A)! EGFP质粒转染的的减毒鼠伤寒沙门氏菌组和口服pVAX1-STEs ! EGFP质粒转染的的减毒鼠伤寒沙门

  17. Vasculogenic mimicry and tumor metastasis.

    Science.gov (United States)

    Zhang, Jingxin; Qiao, Lili; Liang, Ning; Xie, Jian; Luo, Hui; Deng, Guodong; Zhang, Jiandong

    2016-01-01

    Vasculogenic mimicry (VM), a microvascular channel made up of nonendothelial cells, has been accepted as a new model of neovascularization in aggressive tumors, owning to the specific capacity of malignant cells to form vessel-like networks which provide sufficient blood supply for tumor growth. Multiple molecular mechanisms, especially vascular endothelial (VE)-cadherin, erythropoietin-producing hepatocellular receptor A2 (EphA2), phosphatidyl inositol 3-kinase (PI3K), matrix metalloproteinases (MMPs), vascular endothelial growth factor receptor (VEGFR1), and hypoxia inducible factor (HIF)-1a, have been reported to participate in VM formation which is associated with tumor migration and invasion. In addition, hypoxia, cancer stem cells (CSCs) and epithelial-mesenehymal transition (EMT) are regarded as significant factors in VM formation and tumor metastasis. Due to the important effects of VM on tumor progression, a review was carried out in the present study, to synthetically analyze the relationship between VM and tumor metastasis. PMID:27569069

  18. Metabolic exchanges within tumor microenvironment.

    Science.gov (United States)

    Chiarugi, Paola; Cirri, Paolo

    2016-09-28

    Tumor progression toward malignancy often requires a metabolic rewiring of cancer cells to meet changes in metabolic demand to forefront nutrient and oxygen withdrawal, together with strong anabolic requests to match high proliferation rate. Tumor microenvironment highly contributes to metabolic rewiring of cancer cells, fostering complete nutrient exploitation, favoring OXPHOS of lipids and glutamine at the expense of glycolysis and enhancing exchanges via extracellular microvesicles or exosomes of proteins, lipids and small RNAs among tumor and stromal cells. Noteworthy, the same molecular drivers of metabolic reprogramming within tumor and stroma are also able to elicit motility, survival and self-renewal on cancer cells, thereby sustaining successful escaping strategies to circumvent the hostile hypoxic, acidic and inflammatory environment. This review highlights the emerging role of nutrients and vesicle-mediated exchanges among tumor and stromal cells, defining their molecular pathways and offering new perspectives to develop treatments targeting this complex metabolic rewiring. PMID:26546872

  19. Structure and Function of HLA-A*02-Restricted Hantaan Virus Cytotoxic T-Cell Epitope That Mediates Effective Protective Responses in HLA-A2.1/K(b) Transgenic Mice.

    Science.gov (United States)

    Ma, Ying; Cheng, Linfeng; Yuan, Bin; Zhang, Yusi; Zhang, Chunmei; Zhang, Yun; Tang, Kang; Zhuang, Ran; Chen, Lihua; Yang, Kun; Zhang, Fanglin; Jin, Boquan

    2016-01-01

    Hantavirus infections cause severe emerging diseases in humans and are associated with high mortality rates; therefore, they have become a global public health concern. Our previous study showed that the CD8(+) T-cell epitope aa129-aa137 (FVVPILLKA, FA9) of the Hantaan virus (HTNV) nucleoprotein (NP), restricted by human leukocyte antigen (HLA)-A*02, induced specific CD8(+) T-cell responses that controlled HTNV infection in humans. However, the in vivo immunogenicity of peptide FA9 and the effect of FA9-specific CD8(+) T-cell immunity remain unclear. Here, based on a detailed structural analysis of the peptide FA9/HLA-A*0201 complex and functional investigations using HLA-A2.1/K(b) transgenic (Tg) mice, we found that the overall structure of the peptide FA9/HLA-A*0201 complex displayed a typical MHC class I fold with Val2 and Ala9 as primary anchor residues and Val3 and Leu7 as secondary anchor residues that allow peptide FA9 to bind tightly with an HLA-A*0201 molecule. Residues in the middle portion of peptide FA9 extruding out of the binding groove may be the sites that allow for recognition by T-cell receptors. Immunization with peptide FA9 in HLA-A2.1/K(b) Tg mice induced FA9-specific cytotoxic T-cell responses characterized by the induction of high expression levels of interferon-γ, tumor necrosis factor-α, granzyme B, and CD107a. In an HTNV challenge trial, significant reductions in the levels of both the antigens and the HTNV RNA loads were observed in the liver, spleen, and kidneys of Tg mice pre-vaccinated with peptide FA9. Thus, our findings highlight the ability of HTNV epitope-specific CD8(+) T-cell immunity to control HTNV and support the possibility that the HTNV-NP FA9 peptide, naturally processed in vivo in an HLA-A*02-restriction manner, may be a good candidate for the development HTNV peptide vaccines. PMID:27551282

  20. Structure and Function of HLA-A*02-Restricted Hantaan Virus Cytotoxic T-Cell Epitope That Mediates Effective Protective Responses in HLA-A2.1/Kb Transgenic Mice

    Science.gov (United States)

    Ma, Ying; Cheng, Linfeng; Yuan, Bin; Zhang, Yusi; Zhang, Chunmei; Zhang, Yun; Tang, Kang; Zhuang, Ran; Chen, Lihua; Yang, Kun; Zhang, Fanglin; Jin, Boquan

    2016-01-01

    Hantavirus infections cause severe emerging diseases in humans and are associated with high mortality rates; therefore, they have become a global public health concern. Our previous study showed that the CD8+ T-cell epitope aa129–aa137 (FVVPILLKA, FA9) of the Hantaan virus (HTNV) nucleoprotein (NP), restricted by human leukocyte antigen (HLA)-A*02, induced specific CD8+ T-cell responses that controlled HTNV infection in humans. However, the in vivo immunogenicity of peptide FA9 and the effect of FA9-specific CD8+ T-cell immunity remain unclear. Here, based on a detailed structural analysis of the peptide FA9/HLA-A*0201 complex and functional investigations using HLA-A2.1/Kb transgenic (Tg) mice, we found that the overall structure of the peptide FA9/HLA-A*0201 complex displayed a typical MHC class I fold with Val2 and Ala9 as primary anchor residues and Val3 and Leu7 as secondary anchor residues that allow peptide FA9 to bind tightly with an HLA-A*0201 molecule. Residues in the middle portion of peptide FA9 extruding out of the binding groove may be the sites that allow for recognition by T-cell receptors. Immunization with peptide FA9 in HLA-A2.1/Kb Tg mice induced FA9-specific cytotoxic T-cell responses characterized by the induction of high expression levels of interferon-γ, tumor necrosis factor-α, granzyme B, and CD107a. In an HTNV challenge trial, significant reductions in the levels of both the antigens and the HTNV RNA loads were observed in the liver, spleen, and kidneys of Tg mice pre-vaccinated with peptide FA9. Thus, our findings highlight the ability of HTNV epitope-specific CD8+ T-cell immunity to control HTNV and support the possibility that the HTNV-NP FA9 peptide, naturally processed in vivo in an HLA-A*02-restriction manner, may be a good candidate for the development HTNV peptide vaccines. PMID:27551282

  1. Prolonged adenosine A1 receptor activation in hypoxia and pial vessel disruption focal cortical ischemia facilitates clathrin-mediated AMPA receptor endocytosis and long-lasting synaptic inhibition in rat hippocampal CA3-CA1 synapses: differential regulation of GluA2 and GluA1 subunits by p38 MAPK and JNK.

    Science.gov (United States)

    Chen, Zhicheng; Xiong, Cherry; Pancyr, Cassandra; Stockwell, Jocelyn; Walz, Wolfgang; Cayabyab, Francisco S

    2014-07-16

    Activation of presynaptic adenosine A1 receptors (A1Rs) causes substantial synaptic depression during hypoxia/cerebral ischemia, but postsynaptic actions of A1Rs are less clear. We found that A1Rs and GluA2-containing AMPA receptors (AMPARs) form stable protein complexes from hippocampal brain homogenates and cultured hippocampal neurons from Sprague Dawley rats. In contrast, adenosine A2A receptors (A2ARs) did not coprecipitate or colocalize with GluA2-containing AMPARs. Prolonged stimulation of A1Rs with the agonist N(6)-cyclopentyladenosine (CPA) caused adenosine-induced persistent synaptic depression (APSD) in hippocampal brain slices, and APSD levels were blunted by inhibiting clathrin-mediated endocytosis of GluA2 subunits with the Tat-GluA2-3Y peptide. Using biotinylation and membrane fractionation assays, prolonged CPA incubation showed significant depletion of GluA2/GluA1 surface expression from hippocampal brain slices and cultured neurons. Tat-GluA2-3Y peptide or dynamin inhibitor Dynasore prevented CPA-induced GluA2/GluA1 internalization. Confocal imaging analysis confirmed that functional A1Rs, but not A2ARs, are required for clathrin-mediated AMPAR endocytosis in hippocampal neurons. Pharmacological inhibitors or shRNA knockdown of p38 MAPK and JNK prevented A1R-mediated internalization of GluA2 but not GluA1 subunits. Tat-GluA2-3Y peptide or A1R antagonist 8-cyclopentyl-1,3-dipropylxanthine also prevented hypoxia-mediated GluA2/GluA1 internalization. Finally, in a pial vessel disruption cortical stroke model, a unilateral cortical lesion compared with sham surgery reduced hippocampal GluA2, GluA1, and A1R surface expression and also caused synaptic depression in hippocampal slices that was consistent with AMPAR downregulation and decreased probability of transmitter release. Together, these results indicate a previously unknown mechanism for A1R-induced persistent synaptic depression involving clathrin-mediated GluA2 and GluA1 internalization that

  2. Mediation Analysis

    OpenAIRE

    David P. MacKinnon; Fairchild, Amanda J.; Fritz, Matthew S.

    2007-01-01

    Mediating variables are prominent in psychological theory and research. A mediating variable transmits the effect of an independent variable on a dependent variable. Differences between mediating variables and confounders, moderators, and covariates are outlined. Statistical methods to assess mediation and modern comprehensive approaches are described. Future directions for mediation analysis are discussed.

  3. Tumor necrosis factor-α-mediated threonine 435 phosphorylation of p65 nuclear factor-κB subunit in endothelial cells induces vasogenic edema and neutrophil infiltration in the rat piriform cortex following status epilepticus

    Directory of Open Access Journals (Sweden)

    Kim Ji-Eun

    2012-01-01

    Full Text Available Abstract Background Status epilepticus (SE induces severe vasogenic edema in the piriform cortex (PC accompanied by neuronal and astroglial damages. To elucidate the mechanism of SE-induced vasogenic edema, we investigated the roles of tumor necrosis factor (TNF-α in blood-brain barrier (BBB disruption during vasogenic edema and its related events in rat epilepsy models provoked by pilocarpine-induced SE. Methods SE was induced by pilocarpine in rats that were intracerebroventricularly infused with saline-, and soluble TNF p55 receptor (sTNFp55R prior to SE induction. Thereafter, we performed Fluoro-Jade B staining and immunohistochemical studies for TNF-α and NF-κB subunits. Results Following SE, most activated microglia showed strong TNF-α immunoreactivity. In addition, TNF p75 receptor expression was detected in endothelial cells as well as astrocytes. In addition, only p65-Thr435 phosphorylation was increased in endothelial cells accompanied by SMI-71 expression (an endothelial barrier antigen. Neutralization of TNF-α by soluble TNF p55 receptor (sTNFp55R infusion attenuated SE-induced vasogenic edema and neuronal damages via inhibition of p65-Thr435 phosphorylation in endothelial cells. Furthermore, sTNFp55R infusion reduced SE-induced neutrophil infiltration in the PC. Conclusion These findings suggest that impairments of endothelial cell functions via TNF-α-mediated p65-Thr 485 NF-κB phosphorylation may be involved in SE-induced vasogenic edema. Subsequently, vasogenic edema results in extensive neutrophil infiltration and neuronal-astroglial loss.

  4. miR-181a Induces Macrophage Polarized to M2 Phenotype and Promotes M2 Macrophage-mediated Tumor Cell Metastasis by Targeting KLF6 and C/EBPα

    Science.gov (United States)

    Bi, Jia; Zeng, Xianxin; Zhao, Lin; Wei, Qian; Yu, Lifeng; Wang, Xinnan; Yu, Zhaojin; Cao, Yaming; Shan, Fengping; Wei, Minjie

    2016-01-01

    Macrophages can acquire a variety of polarization status and functions: classically activated macrophages (M1 macrophages); alternatively activated macrophages (M2 macrophages). However, the molecular basis of the process is still unclear. Here, this study addresses that microRNA-181a (miR-181a) is a key molecule controlling macrophage polarization. We found that miR-181a is overexpressed in M2 macrophages than in M1 macrophages. miR-181a expression was decreased when M2 phenotype converted to M1, whereas it increased when M1 phenotype converted to M2. Overexpression of miR-181a in M1 macrophages diminished M1 phenotype expression while promoting polarization to the M2 phenotype. In contrast, knockdown of miR-181a in M2 macrophages promoted M1 polarization and diminished M2 phenotype expression. Mechanistically, Bioinformatic analysis revealed that Kruppel-like factor 6 (KLF6) and CCAAT/enhancer binding protein-α (C/EBPα) is a potential target of miR-181a and luciferase assay confirmed that KLF6 and C/EBPα translation is suppressed by miR-181a through interaction with the 3′UTR of KLF6 and C/EBPα mRNA. Further analysis showed that induction of miR-181a suppressed KLF6 and C/EBPα protein expression. Importantly, miR-181a also diminishes M2 macrophages-mediated migration and invasion capacity of tumor cells. Collectively, our results suggest that miR-181a plays a significant role in regulating macrophage polarization through directly target KLF6 and C/EBPα. PMID:27673564

  5. Imaging Tumor Necrosis with Ferumoxytol.

    Directory of Open Access Journals (Sweden)

    Maryam Aghighi

    Full Text Available Ultra-small superparamagnetic iron oxide nanoparticles (USPIO are promising contrast agents for magnetic resonance imaging (MRI. USPIO mediated proton relaxation rate enhancement is strongly dependent on compartmentalization of the agent and can vary depending on their intracellular or extracellular location in the tumor microenvironment. We compared the T1- and T2-enhancement pattern of intracellular and extracellular USPIO in mouse models of cancer and pilot data from patients. A better understanding of these MR signal effects will enable non-invasive characterizations of the composition of the tumor microenvironment.Six 4T1 and six MMTV-PyMT mammary tumors were grown in mice and imaged with ferumoxytol-enhanced MRI. R1 relaxation rates were calculated for different tumor types and different tumor areas and compared with histology. The transendothelial leakage rate of ferumoxytol was obtained by our measured relaxivity of ferumoxytol and compared between different tumor types, using a t-test. Additionally, 3 patients with malignant sarcomas were imaged with ferumoxytol-enhanced MRI. T1- and T2-enhancement patterns were compared with histopathology in a descriptive manner as a proof of concept for clinical translation of our observations.4T1 tumors showed central areas of high signal on T1 and low signal on T2 weighted MR images, which corresponded to extracellular nanoparticles in a necrotic core on histopathology. MMTV-PyMT tumors showed little change on T1 but decreased signal on T2 weighted images, which correlated to compartmentalized nanoparticles in tumor associated macrophages. Only 4T1 tumors demonstrated significantly increased R1 relaxation rates of the tumor core compared to the tumor periphery (p<0.001. Transendothelial USPIO leakage was significantly higher for 4T1 tumors (3.4±0.9x10-3 mL/min/100cm3 compared to MMTV-PyMT tumors (1.0±0.9x10-3 mL/min/100 cm3. Likewise, ferumoxytol imaging in patients showed similar findings with

  6. Imaging probe for tumor malignancy

    Science.gov (United States)

    Tanaka, Shotaro; Kizaka-Kondoh, Shinae; Hiraoka, Hasahiro

    2009-02-01

    Solid tumors possess unique microenvironments that are exposed to chronic hypoxic conditions ("tumor hypoxia"). Although more than half a century has passed since it was suggested that tumor hypoxia correlated with poor treatment outcomes and contributed to cancer recurrence, a fundamental solution to this problem has yet to be found. Hypoxia-inducible factor (HIF-1) is the main transcription factor that regulates the cellular response to hypoxia. It induces various genes whose functions are strongly associated with malignant alteration of the entire tumor. The cellular changes induced by HIF-1 are extremely important targets of cancer therapy, particularly in therapy against refractory cancers. Imaging of the HIF-1-active microenvironment is therefore important for cancer therapy. To image HIF-1activity in vivo, we developed a PTD-ODD fusion protein, POHA, which was uniquely labeled with near-infrared fluorescent dye at the C-terminal. POHA has two functional domains: protein transduction domain (PTD) and VHL-mediated protein destruction motif in oxygen-dependent degradation (ODD) domain of the alpha subunit of HIF-1 (HIF-1α). It can therefore be delivered to the entire body and remain stabilized in the HIF-1-active cells. When it was intravenously injected into tumor-bearing mice, a tumor-specific fluorescence signal was detected in the tumor 6 h after the injection. These results suggest that POHA can be used an imaging probe for tumor malignancy.

  7. Anti-tumor effect of ultrasound microbubbles mediated suicide gene on ovarian carcinoma cells%超声微泡介导自杀基因对卵巢癌细胞的抗瘤效应

    Institute of Scientific and Technical Information of China (English)

    杨艳; 樊萍; 杨竹; 甘胜伟; 王志刚

    2012-01-01

    To explore the anti-tumor effect of ultrasound microbubbles mediated suicide gene on ovarian carcinoma SKOV3 cells. Methods Under the conditions of optimal ultrasound transfection parameters, pORF-HSV1TK plas-mid was transfected into SKOV3 cells by ultrasound mediated microbubbles. Then the cells were divided into negative control group (group C), ultrasound wave irradiation group (group U), liposome group (group L, positive control group), li-posome and ultrasound wave irradiation group (group L + U), liposome, microbubbles and ultrasound wave irradiation group (group L+M+U) as well as microbubbles and ultrasound wave irradiation group (group M+U). The expression of HSV1 TK was detected by using RT-PCR, the inhibition rates of proliferation of SKOV3 cells were detected by using MTT, the changes of quantity and morphology of SKOV3 cells was observed by using light microscope, and the rate of early apop-tosis and cell cycle was detected by using flow cytometry (FCM). Results The expression of HSV1 TK mRNA was the most obvious in group L+M+U. The inhibition rate of proliferation induced by HSV1TK/GCV in SKOV3 was stronger than those in other groups (all P<0. 05). Compared with other groups, SKOV3 cells in group L+M+U decreased significantly with the most abnormal morphology by light microscope. The rate of early apoptosis of SKOV3 cells in group L+M + U was (49. 13±0. 82) % , most of SKOV3 cell cycles were blocked in G1 phase (P<0. 05). Conclusion Ultrasound-mediated microbubbles can enhance the anti-tumor effect of HSV1 TK/GCV system by inhibiting the proliferation of SKOV3 cells and inducing the apoptosis of SKOV3 cells, and the cell cycle is blocked in G1 phase.%目的 探讨超声微泡介导自杀基因对卵巢癌SKOV3细胞抗瘤效应的机制.方法 采用最适超声转染参数,以超声介导微泡转染pORF-HSV1 TK质粒,将SKOV3细胞分成6组:阴性对照组(C组)、超声辐照组(U组)、脂质体组(L组,阳性对照组)、脂质体+超声辐照

  8. Imaging of brain tumors

    International Nuclear Information System (INIS)

    The contents are diagnostic approaches, general features of tumors -hydrocephalus, edema, attenuation and/or intensity value, hemorrhage, fat, contrast enhancement, intra-axial supratentorial tumors - tumors of glial origin, oligodendrogliomas, ependymomas, subependymomas, subependymal giant cell astrocytomas, choroid plexus papilloma; midline tumors - colloid cysts, craniopharyngiomas; pineal region tumors and miscellaneous tumors i.e. primary intracerebral lymphoma, primitive neuroectodermal tumors, hemangioblastomas; extraaxial tumors - meningiomas; nerve sheath tumors -schwannomas, epidermoids, dermoids, lipomas, arachnoid cysts; metastatic tumors (8 refs.)

  9. Testicular tumors

    Directory of Open Access Journals (Sweden)

    Giovanni Rosti

    2011-12-01

    Full Text Available Germ cell tumors of the testes represent a unique paradigm of diseases which can be cured even in extremely advanced phase. Unfortunately, this makes them unique among adult solid tumors. Seminoma and non seminoma are relatively rare with approximatively 25,000 patients in Europe per year, but numbers are increasing world wide. Different strategies are needed depending on stage and prognostic scores. Seminoma is extremely sensitive to radiation therapy and chemotherapy, while all germ cell tumors show a very good response to chemotherapy. Clinical stage I seminoma is currently treated with radiation, single course carboplatin or surveillance policy. Clinical stage I non seminoma can also be approached with different strategies such as retroperitoneal lymph node dissection, observation or one-two courses of standard chemotherapy. Stage II seminoma may be treated with either radiation or chemotherapy, while for all advanced stages chemotherapy is mandatory. Since the mid-eighties PEB (Cisplatin, Etoposide and Bleomycin is the regimen of choice and no other schedule has proved superior in terms of efficacy. Surgery on the residual disease is crucial to the whole strategy and should be performed or attempted in all cases. Consequently, the correct treatment strategy for these tumors does not depend only on the ability of a single physician, but on a skilled team specialized in this particular tumor. Second line therapies (VeIP, PEI, TIP can cure 25%–40% of patients, but improved strategies for resistant tumors are desperately needed. High-dose chemotherapy has shown very good results in some studies while being less impressive in others. In any case, it should remain an option for relapsing patients and could be used in some cases of upfront chemotherapy in patients with slow marker decline, but this should only be considered in referring centers.

  10. Promotion of Tumor Invasion by Cooperation of Granulocytes and Macrophages Activated by Anti-tumor Antibodies

    Directory of Open Access Journals (Sweden)

    Emilio Barbera-Guillem

    1999-11-01

    Full Text Available We investigated the potential role of anti-tumor antibodies and tumor antigens in the formation of immune complexes which promote matrix degradation and angiogenesis. B-cell deficient or B-cell depleted mice showed a reduction in tumor invasion and metastasis. In vitro invasion assays and in vivo models of metastasis showed that anti-sTn antibodies and sTn tumor antigens form complexes which induce granulocytes and macrophages together to mediate tumor invasion and metastasis by processes including extracellular matrix degradation and angiogenesis. These results suggest the existence of a tumor promoting role of a B-cell immune response induced by shed tumor associated antigens of solid, nonlymphoid tumors.

  11. Human neutrophils facilitate tumor cell transendothelial migration.

    LENUS (Irish Health Repository)

    Wu, Q D

    2012-02-03

    Tumor cell extravasation plays a key role in tumor metastasis. However, the precise mechanisms by which tumor cells migrate through normal vascular endothelium remain unclear. In this study, using an in vitro transendothelial migration model, we show that human polymorphonuclear neutrophils (PMN) assist the human breast tumor cell line MDA-MB-231 to cross the endothelial barrier. We found that tumor-conditioned medium (TCM) downregulated PMN cytocidal function, delayed PMN apoptosis, and concomitantly upregulated PMN adhesion molecule expression. These PMN treated with TCM attached to tumor cells and facilitated tumor cell migration through different endothelial monolayers. In contrast, MDA-MB-231 cells alone did not transmigrate. FACScan analysis revealed that these tumor cells expressed high levels of intercellular adhesion molecule-1 (ICAM-1) but did not express CD11a, CD11b, or CD18. Blockage of CD11b and CD18 on PMN and of ICAM-1 on MDA-MB-231 cells significantly attenuated TCM-treated, PMN-mediated tumor cell migration. These tumor cells still possessed the ability to proliferate after PMN-assisted transmigration. These results indicate that TCM-treated PMN may serve as a carrier to assist tumor cell transendothelial migration and suggest that tumor cells can exploit PMN and alter their function to facilitate their extravasation.

  12. Superior sulcus tumors (Pancoast tumors).

    Science.gov (United States)

    Marulli, Giuseppe; Battistella, Lucia; Mammana, Marco; Calabrese, Francesca; Rea, Federico

    2016-06-01

    Superior Sulcus Tumors, frequently termed as Pancoast tumors, are a wide range of tumors invading the apical chest wall. Due to its localization in the apex of the lung, with the potential invasion of the lower part of the brachial plexus, first ribs, vertebrae, subclavian vessels or stellate ganglion, the superior sulcus tumors cause characteristic symptoms, like arm or shoulder pain or Horner's syndrome. The management of superior sulcus tumors has dramatically evolved over the past 50 years. Originally deemed universally fatal, in 1956, Shaw and Paulson introduced a new treatment paradigm with combined radiotherapy and surgery ensuring 5-year survival of approximately 30%. During the 1990s, following the need to improve systemic as well as local control, a trimodality approach including induction concurrent chemoradiotherapy followed by surgical resection was introduced, reaching 5-year survival rates up to 44% and becoming the standard of care. Many efforts have been persecuted, also, to obtain higher complete resection rates using appropriate surgical approaches and involving multidisciplinary team including spine surgeon or vascular surgeon. Other potential treatment options are under consideration like prophylactic cranial irradiation or the addition of other chemotherapy agents or biologic agents to the trimodality approach.

  13. Primary melanoma tumor inhibits metastasis through alterations in systemic hemostasis.

    Science.gov (United States)

    Kirstein, Jennifer M; Hague, M Nicole; McGowan, Patricia M; Tuck, Alan B; Chambers, Ann F

    2016-08-01

    Progression from a primary tumor to distant metastases requires extensive interactions between tumor cells and their microenvironment. The primary tumor is not only the source of metastatic cells but also can also modulate host responses to these cells, leading to an enhancement or inhibition of metastasis. Tumor-mediated stimulation of bone marrow can result in pre-metastatic niche formation and increased metastasis. However, a primary tumor can also inhibit metastasis through concomitant tumor resistance-inhibition of metastatic growth by existing tumor mass. Here, we report that the presence of a B16F10 primary tumor significantly restricted numbers and sizes of experimental lung metastases through reduction of circulating platelets and reduced formation of metastatic tumor cell-associated thrombi. Tumor-bearing mice displayed splenomegaly, correlated with primary tumor size and platelet count. Reduction in platelet numbers in tumor-bearing animals was responsible for metastatic inhibition, as restoration of platelet numbers using isolated platelets re-established both tumor cell-associated thrombus formation and experimental metastasis. Consumption of platelets due to a B16F10 primary tumor is a form of concomitant tumor resistance and demonstrates the systemic impact of a growing tumor. Understanding the interplay between primary tumors and metastases is essential, as clarification of concomitant tumor resistance mechanisms may allow inhibition of metastatic growth following tumor resection. Key messages Mice with a primary B16F10 tumor had reduced metastasis vs. mice without a primary tumor. Tumor-bearing mice had splenomegaly and fewer platelets and tumor-associated thrombi. Restoring platelets restored tumor-associated thrombi and increased metastasis. This work shows the impact that a primary tumor can have on systemic metastasis. Understanding these interactions may lead to improved ways to inhibit metastasis. PMID:27048169

  14. Systemic CD8+ T cell-mediated tumoricidal effects by intratumoral treatment of oncolytic herpes simplex virus with the agonistic monoclonal antibody for murine glucocorticoid-induced tumor necrosis factor receptor.

    Directory of Open Access Journals (Sweden)

    Mikiya Ishihara

    Full Text Available Oncolytic virotherapy combined with immunomodulators is a novel noninvasive strategy for cancer treatment. In this study, we examined the tumoricidal effects of oncolytic HF10, a naturally occurring mutant of herpes simplex virus type-1, combined with an agonistic DTA-1 monoclonal antibody specific for the glucocorticoid-induced tumor necrosis factor receptor. Two murine tumor models were used to evaluate the therapeutic efficacies of HF10 virotherapy combined with DTA-1. The kinetics and immunological mechanisms of DTA-1 in HF10 infection were examined using flow cytometry and immunohistochemistry. Intratumoral administration of HF10 in combination with DTA-1 at a low dose resulted in a more vigorous attenuation of growth of the untreated contralateral as well as the treated tumors than treatment with either HF10 or DTA-1 alone. An accumulation of CD8(+ T cells, including tumor- and herpes simplex virus type-1-specific populations, and a decrease in the number of CD4(+ Foxp3(+ T regulatory cells were seen in both HF10- and DTA-1-treated tumors. Studies using Fc-digested DTA-1 and Fcγ receptor knockout mice demonstrated the direct participation of DTA-1 in regulatory T cell depletion by antibody-dependent cellular cytotoxicity primarily via macrophages. These results indicated the potential therapeutic efficacy of a glucocorticoid-induced tumor necrosis factor receptor-specific monoclonal antibody in oncolytic virotherapy at local tumor sites.

  15. Decrease in self-esteem mediates the association between symptoms of social phobia and depression in middle adolescence in a sex-specific manner: a 2-year follow-up of a prospective population cohort study

    OpenAIRE

    VÀÀnÀnen, Juha-Matti; Isomaa, Rasmus; Kaltiala-Heino, Riittakerttu; Fröjd, Sari; Helminen, Mika; Marttunen, Mauri

    2014-01-01

    Abstract Background Social phobia and depression are common, highly comorbid disorders in middle adolescence. The mechanism underlying this comorbidity, however, is unclear. Decrease in self-esteem caused by the initial disorder might play a decisive role in the development of the subsequent disorder. The present study aimed to determine whether the association between symptoms of social phobia and depression is mediated by decrease in self-esteem in ...

  16. Tetrathiomolybdate inhibits head and neck cancer metastasis by decreasing tumor cell motility, invasiveness and by promoting tumor cell anoikis

    Directory of Open Access Journals (Sweden)

    Merajver Sofia D

    2010-08-01

    Full Text Available Abstract Background The metastatic spread of solid tumors is directly or indirectly responsible for most cancer-related deaths. Tumor metastasis is very complex and this process requires a tumor cell to acquire enhanced motility, invasiveness and anoikis resistance to successfully establish a tumor at a distal site. Metastatic potential of tumor cells is directly correlated with the expression levels of several angiogenic cytokines. Copper is a mandatory cofactor for the function of many of these angiogenic mediators as well as other proteins that play an important role in tumor cell motility and invasiveness. We have previously shown that tetrathiomolybdate (TM is a potent chelator of copper and it mediates its anti-tumor effects by suppressing tumor angiogenesis. However, very little is known about the effect of TM on tumor cell function and tumor metastasis. In this study, we explored the mechanisms underlying TM-mediated inhibition of tumor metastasis. Results We used two in vivo models to examine the effects of TM on tumor metastasis. Animals treated with TM showed a significant decrease in lung metastasis in both in vivo models as compared to the control group. In addition, tumor cells from the lungs of TM treated animals developed significantly smaller colonies and these colonies had significantly fewer tumor cells. TM treatment significantly decreased tumor cell motility and invasiveness by inhibiting lysyl oxidase (LOX activity, FAK activation and MMP2 levels. Furthermore, TM treatment significantly enhanced tumor cell anoikis by activating p38 MAPK cell death pathway and by downregulating XIAP survival protein expression. Conclusions Taken together, these results suggest that TM is a potent suppressor of head and neck tumor metastasis by modulating key regulators of tumor cell motility, invasiveness and anoikis resistance.

  17. Brain tumor - primary - adults

    Science.gov (United States)

    ... Vestibular schwannoma (acoustic neuroma) - adults; Meningioma - adults; Cancer - brain tumor (adults) ... Primary brain tumors include any tumor that starts in the brain. Primary brain tumors can start from brain cells, ...

  18. Brain tumor - children

    Science.gov (United States)

    ... children; Neuroglioma - children; Oligodendroglioma - children; Meningioma - children; Cancer - brain tumor (children) ... The cause of primary brain tumors is unknown. Primary brain tumors may ... (spread to nearby areas) Cancerous (malignant) Brain tumors ...

  19. Tumor-Derived CXCL1 Promotes Lung Cancer Growth via Recruitment of Tumor-Associated Neutrophils

    Directory of Open Access Journals (Sweden)

    Ming Yuan

    2016-01-01

    Full Text Available Neutrophils have a traditional role in inflammatory process and act as the first line of defense against infections. Although their contribution to tumorigenesis and progression is still controversial, accumulating evidence recently has demonstrated that tumor-associated neutrophils (TANs play a key role in multiple aspects of cancer biology. Here, we detected that chemokine CXCL1 was dramatically elevated in serum from 3LL tumor-bearing mice. In vitro, 3LL cells constitutively expressed and secreted higher level of CXCL1. Furthermore, knocking down CXCL1 expression in 3LL cells significantly hindered tumor growth by inhibiting recruitment of neutrophils from peripheral blood into tumor tissues. Additionally, tumor-infiltrated neutrophils expressed higher levels of MPO and Fas/FasL, which may be involved in TAN-mediated inhibition of CD4+ and CD8+ T cells. These results demonstrate that tumor-derived CXCL1 contributes to TANs infiltration in lung cancer which promotes tumor growth.

  20. Pediatric brain tumors

    Energy Technology Data Exchange (ETDEWEB)

    Poussaint, Tina Y. [Department of Radiology, Boston, MA (United States); Panigrahy, Ashok [Children' s Hospital of Pittsburgh of University of Pittsburgh Medical Center, Department of Radiology, Pittsburgh, PA (United States); Huisman, Thierry A.G.M. [Charlotte R. Bloomberg Children' s Center, Johns Hopkins Hospital, Division of Pediatric Radiology and Pediatric Neuroradiology, Baltimore, MD (United States)

    2015-09-15

    Among all causes of death in children from solid tumors, pediatric brain tumors are the most common. This article includes an overview of a subset of infratentorial and supratentorial tumors with a focus on tumor imaging features and molecular advances and treatments of these tumors. Key to understanding the imaging features of brain tumors is a firm grasp of other disease processes that can mimic tumor on imaging. We also review imaging features of a common subset of tumor mimics. (orig.)

  1. Tumor-altered dendritic cell function: implications for anti-tumor immunity

    Directory of Open Access Journals (Sweden)

    Kristian Michael Hargadon

    2013-07-01

    Full Text Available Dendritic cells are key regulators of both innate and adaptive immunity, and the array of immunoregulatory functions exhibited by these cells is dictated by their differentiation, maturation, and activation status. Although a major role for these cells in the induction of immunity to pathogens has long been appreciated, data accumulated over the last several years has demonstrated that DC are also critical regulators of anti-tumor immune responses. However, despite the potential for stimulation of robust anti-tumor immunity by DC, tumor-altered DC function has been observed in many cancer patients and tumor-bearing animals and is often associated with tumor immune escape. Such dysfunction has significant implications for both the induction of natural anti-tumor immune responses as well as the efficacy of immunotherapeutic strategies that target endogenous DC in situ or that employ exogenous DC as part of anti-cancer immunization maneuvers. In this review, the major types of tumor-altered DC function will be described, with emphasis on recent insights into the mechanistic bases for the inhibition of DC differentiation from hematopoietic precursors, the altered programming of DC precursors to differentiate into myeloid-derived suppressor cells or tumor-associated macrophages, the suppression of DC maturation and activation, and the induction of immunoregulatory DC by tumors, tumor-derived factors, and tumor-associated cells within the milieu of the tumor microenvironment. The impact of these tumor-altered cells on the quality of the overall anti-tumor immune response will also be discussed. Finally, this review will also highlight questions concerning tumor-altered DC function that remain unanswered, and it will address factors that have limited advances in the study of this phenomenon in order to focus future research efforts in the field on identifying strategies for interfering with tumor-associated DC dysfunction and improving DC-mediated anti-tumor

  2. Mouse Leydig Tumor Cells

    Directory of Open Access Journals (Sweden)

    Bo-Syong Pan

    2011-01-01

    Full Text Available Cordycepin is a natural pure compound extracted from Cordyceps sinensis (CS. We have demonstrated that CS stimulates steroidogenesis in primary mouse Leydig cell and activates apoptosis in MA-10 mouse Leydig tumor cells. It is highly possible that cordycepin is the main component in CS modulating Leydig cell functions. Thus, our aim was to investigate the steroidogenic and apoptotic effects with potential mechanism of cordycepin on MA-10 mouse Leydig tumor cells. Results showed that cordycepin significantly stimulated progesterone production in dose- and time-dependent manners. Adenosine receptor (AR subtype agonists were further used to treat MA-10 cells, showing that A1, A 2A , A 2B , and A3, AR agonists could stimulate progesterone production. However, StAR promoter activity and protein expression remained of no difference among all cordycepin treatments, suggesting that cordycepin might activate AR, but not stimulated StAR protein to regulate MA-10 cell steroidogenesis. Meanwhile, cordycepin could also induce apoptotic cell death in MA-10 cells. Moreover, four AR subtype agonists induced cell death in a dose-dependent manner, and four AR subtype antagonists could all rescue cell death under cordycepin treatment in MA-10 cells. In conclusion, cordycepin could activate adenosine subtype receptors and simultaneously induce steroidogenesis and apoptosis in MA-10 mouse Leydig tumor cells.

  3. Teratoid Wilms′ tumor - A rare renal tumor

    Directory of Open Access Journals (Sweden)

    Biswanath Mukhopadhyay

    2011-01-01

    Full Text Available Teratoid Wilms′ tumor is an extremely rare renal tumor. We report a case of unilateral teratoid Wilms′ tumor in a 4-year-old girl. The patient was admitted with a right-sided abdominal mass. The mass was arising from the right kidney. Radical nephrectomy was done and the patient had an uneventful recovery. Histopathology report showed teratoid Wilms′ tumor.

  4. [Tumor surgery].

    Science.gov (United States)

    Hausamen, J E

    2000-05-01

    Surgery is still the primary therapeutic approach in treatment of tumors in the head and neck area, dating back to the early nineteenth century. More than 150 years ago, hemimaxillectomies and mandibular resections as well as hemiglossectomies were already performed by leading surgeons. The block principle we are now following dates back to Crile, who also established the principle of cervical lymph node dissection. Ablative oncologic surgery has always been closely linked with plastic and reconstructive surgery, rendering radical surgical interventions possible without disfiguring patients. The development of facial reconstructive surgery proceeded in stages, in the first instance as secondary reconstruction using tube pedicled flaps. The change to the concept of primary reconstruction occurred via arterialized skin flaps and myocutaneous flaps to the widely accepted and performed free tissue transfer. Free bone grafting, inaugurated earlier and still representing the majority of bone grafting, has been supplemented for certain reconstructive purposes by free vascularized bone transfer from various donor sites. Although the five-year-survival rate of carcinoma of the oral cavity has remained unchanged in the past 30 years, distinctive improvements in tumor surgery can be recorded. This is primarily based on improved diagnostics such as modern imaging techniques and the refinement of surgical techniques. The DOSAK has worked out distinctive guidelines for effective ablative oncologic surgery. Surgical approaches offering wide exposure and carrying low morbidity play a decisive role in radical resections. For this reason, midfacial degloving offers an essential improvement for the resection of midface tumors, especially from an aesthetic point of view. Tumors situated deep behind the viscerocranium at the skull base can be clearly exposed either through a lateral approach following a temporary osteotomy of the mandibular ramus or a transmandibular, transmaxillar, or

  5. Studies of Tumor Suppressor Genes via Chromosome Engineering

    Directory of Open Access Journals (Sweden)

    Hiroyuki Kugoh

    2015-12-01

    Full Text Available The development and progression of malignant tumors likely result from consecutive accumulation of genetic alterations, including dysfunctional tumor suppressor genes. However, the signaling mechanisms that underlie the development of tumors have not yet been completely elucidated. Discovery of novel tumor-related genes plays a crucial role in our understanding of the development and progression of malignant tumors. Chromosome engineering technology based on microcell-mediated chromosome transfer (MMCT is an effective approach for identification of tumor suppressor genes. The studies have revealed at least five tumor suppression effects. The discovery of novel tumor suppressor genes provide greater understanding of the complex signaling pathways that underlie the development and progression of malignant tumors. These advances are being exploited to develop targeted drugs and new biological therapies for cancer.

  6. Biological characterization of cetuximab-conjugated gold nanoparticles in a tumor animal model

    Science.gov (United States)

    Kao, Hao-Wen; Lin, Yi-Yu; Chen, Chao-Cheng; Chi, Kwan-Hwa; Tien, Der-Chi; Hsia, Chien-Chung; Lin, Wuu-Jyh; Chen, Fu-Du; Lin, Ming-Hsien; Wang, Hsin-Ell

    2014-07-01

    Gold nanoparticles (AuNPs) are widely applied to the diagnosis and treatment of cancer and can be modified to contain target-specific ligands via gold-thiolate bonding. This study investigated the pharmacokinetics and microdistribution of antibody-mediated active targeting gold nanoparticles in mice with subcutaneous lung carcinoma. We conjugated AuNPs with cetuximab (C225), an antibody-targeting epidermal growth factor receptor (EGFR), and then labeled with In-111, which created EGFR-targeted AuNPs. In vitro studies showed that after a 2 h incubation, the uptake of C225-conjugated AuNPs in high EGFR-expression A549 cells was 14.9-fold higher than that of PEGylated AuNPs; furthermore, uptake was also higher at 3.8-fold when MCF7 cells with lower EGFR-expression were used. MicroSPECT/CT imaging and a biodistribution study conducted by using a A549 tumor xenograft mouse model provided evidence of elevated uptake of the C225-conjugated AuNPs into the tumor cells as a result of active targeting. Moreover, the microdistribution of PEGylated AuNPs revealed that a large portion of AuNPs remained in the tumor interstitium, whereas the C225-conjugated AuNPs displayed enhanced internalization via antibody-mediated endocytosis. Our findings suggest that the anti-EGFR antibody-conjugated AuNPs are likely to be a plausible nano-sized vehicle for drug delivery to EGFR-expressing tumors.

  7. Simultaneous Targeting of Tumor Antigens and the Tumor Vasculature using T Lymphocyte Transfer Synergize to Induce Regression of Established Tumors in Mice

    Science.gov (United States)

    Chinnasamy, Dhanalakshmi; Tran, Eric; Yu, Zhiya; Morgan, Richard A.; Restifo, Nicholas P.; Rosenberg, Steven A.

    2013-01-01

    Most systemic cancer therapies target tumor cells directly though there is increasing interest in targeting the tumor stroma that can comprise a substantial portion of the tumor mass. We report here a synergy between two T cell therapies, one directed against the stromal tumor vasculature and the other directed against antigens expressed on the tumor cell. Simultaneous transfer of genetically engineered syngeneic T cells expressing a chimeric antigen receptor targeting the Vascular Endothelial Growth Factor Receptor-2 (VEGFR-2; KDR) that is over expressed on tumor vasculature and T cells specific for the tumor antigens gp100 (PMEL), TRP-1 (TYRP1), or TRP-2 (DCT) synergistically eradicated established B16 melanoma tumors in mice and dramatically increased the tumor-free survival of mice compared to treatment with either cell type alone or T cells coexpressing these two targeting molecules. Host lymphodepletion prior to cell transfer was required to mediate the anti-tumor effect. The synergistic antitumor response was accompanied by a significant increase in the infiltration and expansion and/or persistence of the adoptively transferred tumor antigen-specific T cells in the tumor microenvironment and thus enhanced their anti-tumor potency. The data presented here emphasize the possible beneficial effects of combining anti-angiogenic with tumor-specific immunotherapeutic approaches for the treatment of patients with cancer. PMID:23633494

  8. Combination PPARγ and RXR Agonist Treatment in Melanoma Cells: Functional Importance of S100A2

    Directory of Open Access Journals (Sweden)

    Joshua P. Klopper

    2010-01-01

    Full Text Available Nuclear hormone receptors, including RXR and PPARγ, represent novel therapeutic targets in melanoma. We have previously shown that the DRO subline of the amelanotic melanoma A375 responds to rexinoid and thiazolidinedione (TZD treatment in vitro and in vivo. We performed microarray analysis of A375(DRO after TZD and combination rexinoid/TZD treatment in which the calcium binding protein S100A2 had increased expression after rexinoid or TZD treatment and a synergistic increase to combination treatment. Increased S100A2 expression is dependent on an intact PPARγ receptor, but it is not sufficient to mediate the antiproliferative effects of rexinoid/TZD treatment. Over expression of S100A2 enhanced the effect of rexinoid and TZD treatment while inhibition of S100A2 expression attenuated the response to rexinoid/TZD treatment, suggesting that S100A2 is necessary for optimal response to RXR and PPARγ activation by respective ligands. In summary, we have identified potential downstream mediators of rexinoid and TZD treatment in a poorly differentiated melanoma and found that alterations in S100A2 expression affect RXR and PPARγ signaling in A375(DRO cells. These studies provide insight into potential mechanisms of tumor response or resistance to these novel therapies.

  9. Acacia ferruginea inhibits tumor progression by regulating inflammatory mediators-(TNF-a, iNOS, COX-2, IL-1β, IL-6, IFN-γ, IL-2, GM-CSF) and pro-angiogenic growth factor- VEGF.

    Science.gov (United States)

    Sakthivel, Kunnathur Murugesan; Guruvayoorappan, Chandrasekaran

    2013-01-01

    The aim of the present investigation was to evaluate the effect of A ferruginea extract on Dalton's lymphoma ascites (DLA) induced tumours in BALB/c mice. Experimental animals received A ferruginea extract (10 mg/ kg.b.wt) intraperitoneally for 14 consecutive days after DLA tumor challenge. Treatment with extract significantly increased the life span, total white blood cell (WBC) count and haemoglobin (Hb) content and decreased the level of serum aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), gamma glutamyl transferase (γ-GT) and nitric oxide (NO) in DLA bearing ascites tumor models. In addition, administration of extract significantly decreased the tumour volume and body weight in a DLA bearing solid tumor model. The levels of pro-inflammatory cytokines such as tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), interleukin-6 (IL-6) and granulocyte monocyte-colony stimulating factor (GM-CSF), as well as pro-angiogenic growth factors such as vascular endothelial growth factor (VEGF) and inducible nitric oxide synthase (iNOS) were elevated in solid tumour controls, but significantly reduced by A ferruginea administration. On the other hand, the extract stimulated the production of interleukin-2 (IL-2) and interferon-gamma (IFN-γ) in animals with DLA induced solid tumours. Increase in CD4+ T-cell population suggested strong immunostimulant activity for this extract. GC/MS and LC/MS analysis showed quinone, quinoline, imidazolidine, pyrrolidine, cyclopentenone, thiazole, pyrazole, catechin and coumarin derivatives as major compounds present in the A ferruginea methanolic extract. Thus, the outcome of the present study suggests that A ferruginea extract has immunomodulatory and tumor inhibitory activities and has the potential to be developed as a natural anticancer agent. PMID:23886206

  10. Chemokines in tumor development and progression

    Energy Technology Data Exchange (ETDEWEB)

    Mukaida, Naofumi, E-mail: naofumim@kenroku.kanazawa-u.ac.jp [Division of Molecular Bioregulation, Cancer Research Institute, Kanazawa University, Kakuma-machi, Kanazawa 920-1192 (Japan); Japan Science and Technology Agency, Core Research for Evolutional Science and Technology, Chiyoda-ku, Tokyo 102-0075 (Japan); Baba, Tomohisa [Division of Molecular Bioregulation, Cancer Research Institute, Kanazawa University, Kakuma-machi, Kanazawa 920-1192 (Japan)

    2012-01-15

    Chemokines were originally identified as mediators of the inflammatory process and regulators of leukocyte trafficking. Subsequent studies revealed their essential roles in leukocyte physiology and pathology. Moreover, chemokines have profound effects on other types of cells associated with the inflammatory response, such as endothelial cells and fibroblasts. Thus, chemokines are crucial for cancer-related inflammation, which can promote tumor development and progression. Increasing evidence points to the vital effects of several chemokines on the proliferative and invasive properties of tumor cells. The wide range of activities of chemokines in tumorigenesis highlights their roles in tumor development and progression.

  11. Effect of DMSA-Fe3O4 nano-magnetic fluid-mediated thermotherapy on rabbit VX2 tumor%石见穿醇提取物对血管内皮细胞生物学行为的影响

    Institute of Scientific and Technical Information of China (English)

    张善兰; 钱晓萍; 刘宝瑞; 胡静; 万莉; 李茹恬; 禹立霞

    2012-01-01

    Objective To investigate the effect of DMSA-Fe3 O4 nano-magnetic fluid-mediated thennotherapy on rabbit VX2 tumor. Methods After establishment of VX2 soft-tissue tumor model of hind limb.20 rabbits were randomly divided into 4 groups of ACmodel control),B(magnetic fluid local injection plus hyperthermia), C (magnetic fluid arterial infusion plus hyperthermia) and D (magnetic fluid intravenous injection plus hyperthermia). CT measurements of tumor size were performed at 2 weeks after treatment. Results In groups of B and C.the temperatures of the center of tumor were [(46. 01 ± 1. 97 )℃ and (40. 38 + 1. 50)℃] and those of tumor marginal zone were [(40. 35±1. 36)℃and (42. 57±1. 80) ℃], respectively, which were significantly higher than [(35. 73 ±1. 32)V and (35. 37±1. 55)℃] in normal muscle tissues and [(35. 69 + 1. 05)℃ and (35. 25± 1.15)℃] in the rectum (P<0.05). The tumor temperatures after thennotherapy were not significantly increased in groups of A and D. On the 14th day after treated, the tumor growth rates of groups of B and C were ( 441. 04 ± 29. 61) % and (354. 81 ± 59. 51) %, respectively, which were significantly lower than (1119. 90± 179. 40)% of group A and (1099. 90 ± 215.11)% of group D (P<0. 05). Conclusion DMSA-Fe3 O4 nano-magnetic fluid-mediated thermotherapy can effectively inhibit the growth of rabbit VX2 tumor.%目的 探讨石见穿醇提取物体外对血管内皮细胞生物学行为的影响.方法 采用人脐静脉内皮细胞( HUVECs)原代培养模型,通过MTT法观察石见穿醇提取物对HUVECs及人肝癌HepG2细胞增殖的影响;通过Transwell小室迁移、体外小管形成实验,观察石见穿醇提取物对HUVECs迁移、小管形成能力的影响.结果 12.5-200 μg/ml的石见穿醇提取物作用于HUVECs48 h,细胞增殖抑制率为17.73%-59.70%,明显高于其作用于人肝癌HepG2细胞的7.19%-39.66%(P<0.01);12.5-200 μg/ml石见穿醇提取物作用HUVECs 12 h

  12. Proliferation behavior of E. coli in a three-dimensional in vitro tumor model.

    Science.gov (United States)

    Elliott, Nelita; Lee, Tae; You, Lingchong; Yuan, Fan

    2011-06-01

    Advances in genetic engineering of non-pathogenic Escherichia coli (E. coli) have made this organism an attractive candidate for gene delivery vehicle. However, proliferation and transport behaviors of E. coli in three-dimensional (3D) tumor environment are still unclear. To this end, we developed a novel microfluidics-based tumor model that permitted direct in situ visualization of E. coli in a 3D environment with densely packed tumor cells (B16.F10 or EMT6). The E. coli was engineered to co-express two proteins invasin and mCherry (inv(+)) so that they had the ability to enter mammalian cells and could be visualized via fluorescence microscopy. E. coli expressing mCherry alone (inv(-)) was used as the control counterpart. The inv(-) bacteria proliferated to a higher extent than inv(+) bacteria in both the 3D tumor model and a 2D monolayer culture model. Meanwhile, the proliferation appeared to be tumor cell type dependent since bacteria did not proliferate as well in the EMT6 model compared to the B16.F10 model. These differences in bacterial proliferation were likely to be caused by inhibitors secreted by tumor cells, as suggested by our data from the bacterial-tumor cell monolayer co-culture experiment. The bacterial proliferation provided a driving force for E. coli spreading in the 3D interstitial space of tumors. These findings are useful for researchers to develop novel strategies for improvement of bacteria-mediated oncolysis or gene delivery in cancer treatment.

  13. Complex Mediation

    DEFF Research Database (Denmark)

    Bødker, Susanne; Andersen, P