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Sample records for a2 mediated tumor

  1. Dual targeting for metastatic breast cancer and tumor neovasculature by EphA2-mediated nanocarriers.

    PubMed

    Guo, Zhaoming; He, Bing; Yuan, Lan; Dai, Wenbing; Zhang, Hua; Wang, Xueqing; Wang, Jiancheng; Zhang, Xuan; Zhang, Qiang

    2015-09-30

    EphA2 is a transmembrane receptor tyrosine kinase that is highly expressed on both tumor neovasculature and some kinds of tumor cells. Here, a homing peptide with a sequence of YSAYPDSVPMMSK (YSA) that binds specifically with EphA2 was utilized to modify the stealth liposomes (YSA-LP). With a particle size of about 85 nm, this functionalized nanocarrier was loaded with fluorescent probe or doxorubicin (DOX) and investigated in vitro and in vivo. In the cellular endocytosis studies in vitro, coumarin-6 loaded YSA-LP exhibited significant specificity to both EphA2-overexpressing tumor cells (MDA-MB-231) and human umbilical vein endothelial cells (HUVEC) via a YSA mediated interaction. In a MDA-MB-231 xenograft tumor mouse model, DiR-loaded YSA-LP showed more lasting accumulation in tumor tissue by small animal imaging compared to unmodified liposomes (LP). Further, YSA-LP greatly facilitated the efficacy of DOX loaded against both tumor cells and tumor angiogenesis in the same mouse model, evidenced by inhibiting tumor growth, metastasis and CD31 expression as well as inducing cancer cell apoptosis. Additionally, YSA-LP (DOX) showed relatively low systemic and cardiac toxicity compared with control groups. In conclusion, YSA might be a promising targeting motif for EphA2-overexpressing tumor cells and tumor neovasculature, which could be used to mediate drug delivery for chemotherapy agents. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Blockade of A2b Adenosine Receptor Reduces Tumor Growth and Immune Suppression Mediated by Myeloid-Derived Suppressor Cells in a Mouse Model of Melanoma12

    PubMed Central

    Iannone, Raffaella; Miele, Lucio; Maiolino, Piera; Pinto, Aldo; Morello, Silvana

    2013-01-01

    The A2b receptor (A2bR) belongs to the adenosine receptor family. Emerging evidence suggest that A2bR is implicated in tumor progression in some murine tumor models, but the therapeutic potential of targeting A2bR in melanoma has not been examined. This study first shows that melanoma-bearing mice treated with Bay 60-6583, a selective A2bR agonist, had increased melanoma growth. This effect was associated with higher levels of immune regulatory mediators interleukin-10 (IL-10) and monocyte chemoattractant protein 1 (MCP-1) and accumulation of tumor-associated CD11b positive Gr1 positive cells (CD11b+Gr1+) myeloid-derived suppressor cells (MDSCs). Depletion of CD11b+Gr1+ cells completely reversed the protumor activity of Bay 60-6583. Conversely, pharmacological blockade of A2bR with PSB1115 reversed immune suppression in the tumor microenvironment, leading to a significant melanoma growth delay. PSB1115 treatment reduced both levels of IL-10 and MCP-1 and CD11b+Gr1+ cell number in melanoma lesions. These effects were associated with higher frequency of tumor-infiltrating CD8 positive (CD8+) T cells and natural killer T (NKT) cells and increased levels of T helper 1 (Th1)-like cytokines. Adoptive transfer of CD11b+Gr1+ cells abrogated the antitumor activity of PSB1115. These data suggest that the antitumor activity of PSB1115 relies on its ability to lower accumulation of tumor-infiltrating MDSCs and restore an efficient antitumor T cell response. The antitumor effect of PSB1115 was not observed in melanoma-bearing nude mice. Furthermore, PSB1115 enhanced the antitumor efficacy of dacarbazine. These data indicate that A2bR antagonists such as PSB1115 should be investigated as adjuvants in the treatment of melanoma. PMID:24403862

  3. EphrinA1-EphA2 interaction-mediated apoptosis and Flt3L-induced immunotherapy inhibits tumor growth in a breast cancer mouse model

    PubMed Central

    Tandon, Manish; Vemula, Sai V.; Sharma, Anurag; Ahi, Yadvinder S.; Mittal, Shalini; Bangari, Dinesh S.; Mittal, Suresh K.

    2014-01-01

    Background The receptor tyrosine kinase EphA2 is overexpressed in several types of cancers and is currently being pursued as a target for breast cancer therapeutics. The EphA2 ligand EphrinA1 induces EphA2 phosphorylation and intracellular internalization and degradation, thus inhibiting tumor progression. The hematopoietic growth factor, FMS-like tyrosine kinase receptor ligand (Flt3L), promotes expansion and mobilization of functional dendritic cells. Methods We tested the EphrinA1-EphA2 interaction in MDA-MB-231 breast cancer cells focusing on the receptor-ligand-mediated apoptosis of breast cancer cells. In order to determine whether the EphrinA1-EphA2 interaction-associated apoptosis and Flt3L-mediated immunotherapy would have an additive effect in inhibiting tumor growth, we used an immunocompetent mouse model of breast cancer to evaluate intratumoral (i.t.) inoculation strategies with human adenovirus (HAd) vectors expressing either EphrinA1 (HAd-EphrinA1-Fc), Flt3L (HAd-Flt3L) or a combination of EphrinA1-Fc + Flt3L (HAd-EphrinA1-Fc + HAd-Flt3L). Results In vitro analysis demonstrated that an EphrinA1-EphA2 interaction led to apoptosis-related changes in breast cancer cells. In vivo, three i.t. inoculations of HAd-EphrinA1-Fc showed potent inhibition of tumor growth. Furthermore, increased inhibition in tumor growth was observed with the combination of HAd-EphrinA1-Fc and HAd-Flt3L accompanied by the generation of an anti-tumor adaptive immune response. Conclusions The results indicating induction of apoptosis and inhibition of mammary tumor growth show the potential therapeutic benefits of HAd-EphrinA1-Fc. In combination with HAd-Flt3L, this represents a promising strategy to effectively induce mammary tumor regression by HAd vector-based therapy. PMID:22228563

  4. Transactivation of the Receptor-tyrosine Kinase Ephrin Receptor A2 Is Required for the Low Molecular Weight Hyaluronan-mediated Angiogenesis That Is implicated in Tumor Progression*

    PubMed Central

    Lennon, Frances E; Mirzapoiazova, Tamara; Mambetsariev, Nurbek; Mambetsariev, Bolot; Salgia, Ravi; Singleton, Patrick A.

    2014-01-01

    Angiogenesis or the formation of new blood vessels is important in the growth and metastatic potential of various cancers. Therefore, understanding the mechanism(s) by which angiogenesis occurs can have important therapeutic implications in numerous malignancies. We and others have demonstrated that low molecular weight hyaluronan (LMW-HA, ∼2500 Da) promotes endothelial cell (EC) barrier disruption and angiogenesis. However, the mechanism(s) by which this occurs is poorly defined. Our data indicate that treatment of human EC with LMW-HA induced CD44v10 association with the receptor-tyrosine kinase, EphA2, transactivation (tyrosine phosphorylation) of EphA2, and recruitment of the PDZ domain scaffolding protein, PATJ, to the cell periphery. Silencing (siRNA) CD44, EphA2, PATJ, or Dbs (RhoGEF) expression blocked LMW-HA-mediated angiogenesis (EC proliferation, migration, and tubule formation). In addition, silencing EphA2, PATJ, Src, or Dbs expression blocked LMW-HA-mediated RhoA activation. To translate our in vitro findings, we utilized a novel anginex/liposomal targeting of murine angiogenic endothelium with either CD44 or EphA2 siRNA and observed inhibition of LMW-HA-induced angiogenesis in implanted Matrigel plugs. Taken together, these results indicate LMW-HA-mediated transactivation of EphA2 is required for PATJ and Dbs membrane recruitment and subsequent RhoA activation required for angiogenesis. These results suggest that targeting downstream effectors of LMW-HA could be a useful therapeutic intervention for angiogenesis-associated diseases including tumor progression. PMID:25023279

  5. Identification of a human telomerase reverse transcriptase peptide of low affinity for HLA A2.1 that induces cytotoxic T lymphocytes and mediates lysis of tumor cells

    PubMed Central

    Hernández, Javier; García-Pons, Francisco; Lone, Yu Chun; Firat, Huseyin; Schmidt, Joseph D.; Langlade-Demoyen, Pierre; Zanetti, Maurizio

    2002-01-01

    Telomerase reverse transcriptase (TRT) is a tumor-associated antigen expressed in the vast majority of human tumors and is presently one of the most promising target candidates for a therapeutic cancer vaccine. TRT is also expressed at low level in selected tissues and should be considered a self antigen. In the present study we sought to develop cytotoxic T lymphocytes (CTL) responses directed against human (h)TRT peptides with low relative affinity for which the available repertoire is to be preferentially spared from tolerance. This was accomplished by using analogue peptides of hTRT whose relative affinity for the MHC was increased by a targeted (→Tyr) substitution in position one. By immunizing HLA A2.1 transgenic mice with these analogue peptides, we identified one such low relative affinity peptide (p572) that is endogenously processed and presented by HLA A2.1 in tumor cells, and is recognized by specific CTL. We used the highly immunogenic analogue peptide to successfully induce TRT-specific CTL in cancer patients and normal donors. CTL against p572-lysed human and mouse tumor cells but not activated autologous B cells. This peptide represents, therefore, an important candidate component of a cancer vaccine based on a TRT substrate and validates the strategy of targeting peptides with low affinity for the MHC for cancer immunotherapy. PMID:12218171

  6. Impaired tumor microenvironment in EphA2-deficient mice inhibits tumor angiogenesis and metastatic progression.

    PubMed

    Brantley-Sieders, Dana M; Fang, Wei Bin; Hicks, Donna J; Zhuang, Guanglei; Shyr, Yu; Chen, Jin

    2005-11-01

    EphA2 belongs to a unique family of receptor tyrosine kinases that play critical roles in development and disease. Since EphA2 is required for ephrin-A1 ligand-induced vascular remodeling and is overexpressed in a variety of vascularized human adenocarcinomas, we assessed tumor angiogenesis and metastatic progression in EphA2-deficient host animals. 4T1 metastatic mammary adenocarcinoma cells transplanted subcutaneously and orthotopically into EphA2-deficient female mice displayed decreased tumor volume, tumor cell survival, microvascular density, and lung metastasis relative to tumor-bearing littermate controls. To determine if the phenotype in EphA2-deficient mice was endothelial cell intrinsic, we also analyzed endothelial cells isolated from EphA2-deficient animals for their ability to incorporate into tumor vessels in vivo, as well as to migrate in response to tumor-derived signals in vitro. EphA2-deficient endothelial cells displayed impaired survival and failed to incorporate into tumor microvessels in vivo, and displayed impaired tumor-mediated migration in vitro relative to controls. These data suggest that host EphA2 receptor tyrosine kinase function is required in the tumor microenvironment for tumor angiogenesis and metastatic progression.

  7. EphrinA1-EphA2 interaction-mediated apoptosis and FMS-like tyrosine kinase 3 receptor ligand-induced immunotherapy inhibit tumor growth in a breast cancer mouse model.

    PubMed

    Tandon, Manish; Vemula, Sai V; Sharma, Anurag; Ahi, Yadvinder S; Mittal, Shalini; Bangari, Dinesh S; Mittal, Suresh K

    2012-02-01

    The receptor tyrosine kinase EphA2 is overexpressed in several types of cancers and is currently being pursued as a target for breast cancer therapeutics. The EphA2 ligand EphrinA1 induces EphA2 phosphorylation and intracellular internalization and degradation, thus inhibiting tumor progression. The hematopoietic growth factor, FMS-like tyrosine kinase 3 receptor ligand (Flt3L), promotes expansion and mobilization of functional dendritic cells. We tested the EphrinA1-EphA2 interaction in MDA-MB-231 breast cancer cells focusing on the receptor-ligand-mediated apoptosis of breast cancer cells. To determine whether EphrinA1-EphA2 interaction-associated apoptosis and Flt3L-mediated immunotherapy would have an additive effect in inhibiting tumor growth, we used an immunocompetent mouse model of breast cancer to evaluate intratumoral (i.t.) inoculation strategies with human adenovirus (HAd) vectors expressing either EphrinA1 (HAd-EphrinA1-Fc), Flt3L (HAd-Flt3L) or a combination of EphrinA1-Fc + Flt3L (HAd-EphrinA1-Fc + HAd-Flt3L). In vitro analysis demonstrated that an EphrinA1-EphA2 interaction led to apoptosis-related changes in breast cancer cells. In vivo, three i.t. inoculations of HAd-EphrinA1-Fc showed potent inhibition of tumor growth. Furthermore, increased inhibition in tumor growth was observed with the combination of HAd-EphrinA1-Fc and HAd-Flt3L accompanied by the generation of an anti-tumor adaptive immune response. The results obtained in the present study, indicating the induction of apoptosis and inhibition of mammary tumor growth, show the potential therapeutic benefits of HAd-EphrinA1-Fc. In combination with HAd-Flt3L, this represents a promising strategy for effectively inducing mammary tumor regression by HAd vector-based therapy. Copyright © 2012 John Wiley & Sons, Ltd.

  8. Autocrine IL-6 mediates pituitary tumor senescence

    PubMed Central

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

    2017-01-01

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

  9. Proinflammatory mediators and genetic background in oncogene mediated tumor progression.

    PubMed

    Russell, John P; Engiles, Julie B; Rothstein, Jay L

    2004-04-01

    RET/PTC3 (RP3) is an oncogenic fusion protein which is frequently expressed in papillary thyroid carcinomas and has been detected in thyroid tissue from patients diagnosed with Hashimoto's thyroiditis. The constitutive activation of the tyrosine kinase domain in the carboxyl-terminal end of RP3 induces signaling pathways within thyrocytes and causes cellular transformation. One of the signaling pathways activated in RP3-expressing cells involves the activity of the transcription factor NF-kappaB and the production of downstream targets including GM-CSF and macrophage chemotactic protein 1. These factors are known to be immunostimulatory, making RP3 a molecular adjuvant and potentially promoting tissue-specific immunity. However compelling, these in vitro data do not reliably predict gene function in vivo or the cumulative effects of time-dependent processes such as angiogenesis, inflammation, or the influence of genetic background. To address these issues, we analyzed the production of proinflammatory mediators in mouse thyroid organs and demonstrate consistency with in vitro studies performed previously that Il1alpha, Il1beta, Il6, and Tnfalpha and the enzyme Cox2 are produced by RP3-transgenic thyroid tissue, but absent from nontransgenic thyroids. Furthermore, we find that that the genetic background of the host is important in the observed RP3-induced inflammation and tumor progression. These findings provide support for the notion that oncogene-induced cytokine secretion is important for the development and progression of thyroid carcinomas in genetically permissive hosts.

  10. Exosomes and tumor-mediated immune suppression

    PubMed Central

    2016-01-01

    Tumor-derived exosomes (TEX) are harbingers of tumor-induced immune suppression: they carry immunosuppressive molecules and factors known to interfere with immune cell functions. By delivering suppressive cargos consisting of proteins similar to those in parent tumor cells to immune cells, TEX directly or indirectly influence the development, maturation, and antitumor activities of immune cells. TEX also deliver genomic DNA, mRNA, and microRNAs to immune cells, thereby reprogramming functions of responder cells to promote tumor progression. TEX carrying tumor-associated antigens can interfere with antitumor immunotherapies. TEX also have the potential to serve as noninvasive biomarkers of tumor progression. In the tumor microenvironment, TEX may be involved in operating numerous signaling pathways responsible for the downregulation of antitumor immunity. PMID:26927673

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

    PubMed Central

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

    2015-01-01

    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. PMID:26460736

  12. Stem and progenitor cell-mediated tumor selective gene therapy.

    PubMed

    Aboody, K S; Najbauer, J; Danks, M K

    2008-05-01

    The poor prognosis for patients with aggressive or metastatic tumors and the toxic side effects of currently available treatments necessitate the development of more effective tumor-selective therapies. Stem/progenitor cells display inherent tumor-tropic properties that can be exploited for targeted delivery of anticancer genes to invasive and metastatic tumors. Therapeutic genes that have been inserted into stem cells and delivered to tumors with high selectivity include prodrug-activating enzymes (cytosine deaminase, carboxylesterase, thymidine kinase), interleukins (IL-2, IL-4, IL-12, IL-23), interferon-beta, apoptosis-promoting genes (tumor necrosis factor-related apoptosis-inducing ligand) and metalloproteinases (PEX). We and others have demonstrated that neural and mesenchymal stem cells can deliver therapeutic genes to elicit a significant antitumor response in animal models of intracranial glioma, medulloblastoma, melanoma brain metastasis, disseminated neuroblastoma and breast cancer lung metastasis. Most studies reported reduction in tumor volume (up to 90%) and increased survival of tumor-bearing animals. Complete cures have also been achieved (90% disease-free survival for >1 year of mice bearing disseminated neuroblastoma tumors). As we learn more about the biology of stem cells and the molecular mechanisms that mediate their tumor-tropism and we identify efficacious gene products for specific tumor types, the clinical utility of cell-based delivery strategies becomes increasingly evident.

  13. Nanoparticle-mediated cryosurgery for tumor therapy.

    PubMed

    Hou, Yi; Sun, Ziqiao; Rao, Wei; Liu, Jing

    2018-02-01

    Cryosurgery is an energy-based surgical technique. It is minimally invasive and has fewer side effects than surgical resection. However, its insufficient freezing to target tumor and unavoidable injury to healthy tissue have restricted its success. Nano-cryosurgery is the combination of cryogenic biomedicine and nanotechnology. Its principle is to introduce a nanoparticle solution into target tissues to maximize heat transfer, lower the end temperature, increase ice ball formation, and prevent healthy tissues from being frozen. This review covers common nanoplatforms for nano-cryosurgery. The characteristics, advantages, potential challenges, future prospects of applying nano-cryosurgery are discussed in detail. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Intracellular targeting of annexin A2 inhibits tumor cell adhesion, migration, and in vivo grafting.

    PubMed

    Staquicini, Daniela I; Rangel, Roberto; Guzman-Rojas, Liliana; Staquicini, Fernanda I; Dobroff, Andrey S; Tarleton, Christy A; Ozbun, Michelle A; Kolonin, Mikhail G; Gelovani, Juri G; Marchiò, Serena; Sidman, Richard L; Hajjar, Katherine A; Arap, Wadih; Pasqualini, Renata

    2017-06-26

    Cytoskeletal-associated proteins play an active role in coordinating the adhesion and migration machinery in cancer progression. To identify functional protein networks and potential inhibitors, we screened an internalizing phage (iPhage) display library in tumor cells, and selected LGRFYAASG as a cytosol-targeting peptide. By affinity purification and mass spectrometry, intracellular annexin A2 was identified as the corresponding binding protein. Consistently, annexin A2 and a cell-internalizing, penetratin-fused version of the selected peptide (LGRFYAASG-pen) co-localized and specifically accumulated in the cytoplasm at the cell edges and cell-cell contacts. Functionally, tumor cells incubated with LGRFYAASG-pen showed disruption of filamentous actin, focal adhesions and caveolae-mediated membrane trafficking, resulting in impaired cell adhesion and migration in vitro. These effects were paralleled by a decrease in the phosphorylation of both focal adhesion kinase (Fak) and protein kinase B (Akt). Likewise, tumor cells pretreated with LGRFYAASG-pen exhibited an impaired capacity to colonize the lungs in vivo in several mouse models. Together, our findings demonstrate an unrecognized functional link between intracellular annexin A2 and tumor cell adhesion, migration and in vivo grafting. Moreover, this work uncovers a new peptide motif that binds to and inhibits intracellular annexin A2 as a candidate therapeutic lead for potential translation into clinical applications.

  15. Nitric oxide short-circuits interleukin-12-mediated tumor regression.

    PubMed

    Egilmez, Nejat K; Harden, Jamie L; Virtuoso, Lauren P; Schwendener, Reto A; Kilinc, Mehmet O

    2011-06-01

    Interleukin-12 (IL-12) can promote tumor regression via activation of multiple lymphocytic and myelocytic effectors. Whereas the cytotoxic mechanisms employed by T/NK/NKT cells in IL-12-mediated tumor kill are well defined, the antitumor role of macrophage-produced cytotoxic metabolites has been more controversial. To this end, we investigated the specific role of nitric oxide (NO), a major macrophage effector molecule, in post-IL-12 tumor regression. Analysis of tumors following a single intratumoral injection of slow-release IL-12 microspheres showed an IFNγ-dependent sevenfold increase in inducible nitric oxide synthase (iNOS) expression within 48 h. Flow cytometric analysis of tumor-resident leukocytes and in vivo depletion studies identified CD11b(+) F4/80(+) Gr1(lo) macrophages as the primary source of iNOS. Blocking of post-therapy iNOS activity with N-nitro-L: -arginine methyl ester (L-NAME) dramatically enhanced tumor suppression revealing the inhibitory effect of NO on IL-12-driven antitumor immunity. Superior tumor regression in mice receiving combination treatment was associated with enhanced survival and proliferation of activated tumor-resident CD8+ T-effector/memory cells (Tem). These findings demonstrate that macrophage-produced NO negatively regulates the antitumor activity of IL-12 via its detrimental effects on CD8+ T cells and identify L-NAME as a potent adjuvant in IL-12 therapy of cancer.

  16. Exosome mediated communication within the tumor microenvironment.

    PubMed

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

    2015-12-10

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

  17. Acid-Mediated Tumor Proteolysis: Contribution of Cysteine Cathepsins12

    PubMed Central

    Rothberg, Jennifer M; Bailey, Kate M; Wojtkowiak, Jonathan W; Ben-Nun, Yael; Bogyo, Matthew; Weber, Ekkehard; Moin, Kamiar; Blum, Galia; Mattingly, Raymond R; Gillies, Robert J; Sloane, Bonnie F

    2013-01-01

    One of the noncellular microenvironmental factors that contribute to malignancy of solid tumors is acidic peritumoral pH. We have previously demonstrated that extracellular acidosis leads to localization of the cysteine pro-tease cathepsin B on the tumor cell membrane and its secretion. The objective of the present study was to determine if an acidic extracellular pH such as that observed in vivo (i.e., pHe 6.8) affects the activity of proteases, e.g., cathepsin B, that contribute to degradation of collagen IV by tumor cells when grown in biologically relevant three-dimensional (3D) cultures. For these studies, we used 1) 3D reconstituted basement membrane overlay cultures of human carcinomas, 2) live cell imaging assays to assess proteolysis, and 3) in vivo imaging of active tumor proteases. At pHe 6.8, there were increases in pericellular active cysteine cathepsins and in degradation of dye-quenched collagen IV, which was partially blocked by a cathepsin B inhibitor. Imaging probes for active cysteine cathepsins localized to tumors in vivo. The amount of bound probe decreased in tumors in bicarbonate-treated mice, a treatment previously shown to increase peritumoral pHe and reduce local invasion of the tumors. Our results are consistent with the acid-mediated invasion hypothesis and with a role for cathepsin B in promoting degradation of a basement membrane protein substrate, i.e., type IV collagen, in an acidic peritumoral environment. PMID:24204192

  18. Elevated Slit2 Activity Impairs VEGF-Induced Angiogenesis and Tumor Neovascularization in EphA2-Deficient Endothelium.

    PubMed

    Youngblood, Victoria; Wang, Shan; Song, Wenqiang; Walter, Debra; Hwang, Yoonha; Chen, Jin; Brantley-Sieders, Dana M

    2015-03-01

    Angiogenic remodeling during embryonic development and in adult tissue homeostasis is orchestrated by cooperative signaling between several distinct molecular pathways, which are often exploited by tumors. Indeed, tumors upregulate proangiogenic molecules while simultaneously suppressing angiostatic pathways to recruit blood vessels for growth, survival, and metastatic spread. Understanding how cancers exploit proangiogenic and antiangiogenic signals is a key step in developing new, molecularly targeted antiangiogenic therapies. While EphA2, a receptor tyrosine kinase (RTK), is required for VEGF-induced angiogenesis, the mechanism through which these pathways intersect remains unclear. Slit2 expression is elevated in EphA2-deficient endothelium, and here it is reported that inhibiting Slit activity rescues VEGF-induced angiogenesis in cell culture and in vivo, as well as VEGF-dependent tumor angiogenesis, in EphA2-deficient endothelial cells and animals. Moreover, blocking Slit activity or Slit2 expression in EphA2-deficient endothelial cells restores VEGF-induced activation of Src and Rac, both of which are required for VEGF-mediated angiogenesis. These data suggest that EphA2 suppression of Slit2 expression and Slit angiostatic activity enables VEGF-induced angiogenesis in vitro and in vivo, providing a plausible mechanism for impaired endothelial responses to VEGF in the absence of EphA2 function. Modulation of angiostatic factor Slit2 by EphA2 receptor regulates endothelial responses to VEGF-mediated angiogenesis and tumor neovascularization. ©2014 American Association for Cancer Research.

  19. Stat3 mediates myeloid cell–dependent tumor angiogenesis in mice

    PubMed Central

    Kujawski, Maciej; Kortylewski, Marcin; Lee, Heehyoung; Herrmann, Andreas; Kay, Heidi; Yu, Hua

    2008-01-01

    The underlying molecular mechanisms that cause immune cells, mediators of our defense system, to promote tumor invasion and angiogenesis remain incompletely understood. Constitutively activated Stat3 in tumor cells has been shown to promote tumor invasion and angiogenesis. Therefore, we sought to determine whether Stat3 activation in tumor-associated inflammatory cells has a similar function. We found that Stat3 signaling mediates multidirectional crosstalk among tumor cells, myeloid cells in the tumor stroma, and ECs that contributes to tumor angiogenesis in mice. Myeloid-derived suppressor cells and macrophages isolated from mouse tumors displayed activated Stat3 and induced angiogenesis in an in vitro tube formation assay via Stat3 induction of angiogenic factors, including VEGF and bFGF. Stat3-regulated factors produced by both tumor cells and tumor-derived myeloid cells also induced constitutive activation of Stat3 in tumor endothelium, and inhibiting Stat3 in ECs substantially reduced in vitro tumor factor–induced endothelial migration and tube formation. In vivo assays demonstrated the requirement for Stat3 signaling in tumor-associated myeloid cells for tumor angiogenesis. Our results indicate that, by virtue of the ability of Stat3 in tumor cells and tumor-derived myeloid cells to upregulate expression of factors that activate Stat3 in ECs, Stat3 mediates multidirectional crosstalk among tumor cells, tumor-associated myeloid cells, and ECs that contributes to tumor angiogenesis. PMID:18776941

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

    PubMed

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

    2015-12-01

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

  1. Regorafenib inhibits colorectal tumor growth through PUMA-mediated apoptosis

    PubMed Central

    Chen, Dongshi; Wei, Liang; Yu, Jian; Zhang, Lin

    2014-01-01

    Purpose Regorafenib, a multi-kinase inhibitor targeting the Ras/Raf/MEK/ERK pathway, has recently been approved for the treatment of metastatic colorectal cancer (CRC). However, the mechanisms of action of regorafenib in CRC cells have been unclear. We investigated how regorafenib suppresses CRC cell growth and potentiates effects of other chemotherapeutic drugs. Experimental Design We determined whether and how regorafenib induces the expression of PUMA, a p53 target and a critical mediator of apoptosis in CRC cells. We also investigated whether PUMA is necessary for the killing and chemosensitization effects of regorafenib in CRC cells. Furthermore, xenograft tumors were used to test if PUMA mediates the in vivo antitumor, antiangiogenic and chemosensitization effects of regorafenib. Results We found that regorafenib treatment induces PUMA in CRC cells irrespective of p53 status through the NF-κB pathway following ERK inhibition and glycogen synthase kinase 3β (GSK3β) activation. Upregulation of PUMA is correlated with apoptosis induction in different CRC cell lines. PUMA is necessary for regorafenib-induced apoptosis in CRC cells. Chemosensitization by regorafenib is mediated by enhanced PUMA induction through different pathways. Furthermore, deficiency in PUMA abrogates the in vivo antitumor, antiangiogenic and chemosensitization effects of regorafenib. Conclusions Our results demonstrate a key role of PUMA in mediating the anticancer effects of regorafenib in CRC cells. They suggest that PUMA induction can be used as an indicator of regorafenib sensitivity, and also provide a rationale for manipulating the apoptotic machinery to improve the therapeutic efficacy of regorafenib and other targeted drugs. PMID:24763611

  2. Elevated Slit2 Activity Impairs VEGF-induced Angiogenesis and Tumor Neovascularization in EphA2-deficient Endothelium

    PubMed Central

    Youngblood, Victoria; Wang, Shan; Song, Wenqiang; Walter, Debra; Hwang, Yoonha; Chen, Jin; Brantley-Sieders, Dana M.

    2015-01-01

    Angiogenic remodeling during embryonic development and in adult tissue homeostasis is orchestrated by cooperative signaling between several distinct molecular pathways, which are often exploited by tumors. Indeed, tumors upregulate pro-angiogenic molecules while simultaneously suppressing angiostatic pathways in order to recruit blood vessels for growth, survival, and metastatic spread. Understanding how cancers exploit pro- and anti-angiogenic signals is a key step in developing new, molecularly targeted anti-angiogenic therapies. While EphA2, a receptor tyrosine kinase (RTK), is required for vascular endothelial growth factor (VEGF)-induced angiogenesis, the mechanism through which these pathways intersect remains unclear. Slit2 expression is elevated in EphA2-deficient endothelium, and here it is reported that inhibiting Slit activity rescues VEGF-induced angiogenesis in cell culture and in vivo, as well as VEGF-dependent tumor angiogenesis, in EphA2-deficient endothelial cells and animals. Moreover, blocking Slit activity or Slit2 expression in EphA2-deficient endothelial cells restores VEGF-induced activation of Src and Rac, both of which are required for VEGF-mediated angiogenesis. These data suggest that EphA2 suppression of Slit2 expression and Slit angiostatic activity enables VEGF-induced angiogenesis in vitro and in vivo, providing a plausible mechanism for impaired endothelial responses to VEGF in the absence of EphA2 function. PMID:25504371

  3. Proteolysis of EphA2 converts it from a tumor suppressor to an oncoprotein

    PubMed Central

    KOSHIKAWA, Naohiko; HOSHINO, Daisuke; TANIGUCHI, Hiroaki; MINEGISHI, Tomoko; TOMARI, Taizo; NAM, Sung-Ouk; AOKI, Mikiko; SUETA, Takayuki; NAKAGAWA, Takashi; MIYAMOTO, Shingo; NABESHIMA, Kazuki; WEAVER, Alissa M.; SEIKI, Motoharu

    2015-01-01

    Eph receptor tyrosine kinases are considered candidate therapeutic targets in cancer, but they can exert opposing effects on cell growth. In presence of its ligands, Eph receptor EphA2 suppresses signaling by other growth factor receptors, including ErbB, whereas ligand-independent activation of EphA2 augments ErbB signaling. To deploy EphA2-targeting drugs effectively in tumors, the anti-oncogenic ligand-dependent activation state of EphA2 must be discriminated from its oncogenic ligand-independent state. Since the molecular basis for the latter is little understood, we investigated how the activation state of EphA2 can be switched in tumor tissue. We found that ligand-binding domain of EphA2 is cleaved frequently by the membrane metalloproteinase MT1-MMP, a powerful modulator of the pericellular environment in tumor cells. EphA2 immunostaining revealed a significant loss of the N-terminal portion of EphA2 in areas of tumor tissue that expressed MT1-MMP. Moreover, EphA2 phosphorylation patterns that signify ligand-independent activation were observed specifically in these areas of tumor tissue. Mechanistic experiments revealed that processing of EphA2 by MT1-MMP promoted ErbB signaling, anchorage-independent growth, and cell migration. Conversely, expression of a proteolysis-resistant mutant of EphA2 prevented tumorigenesis and metastasis of human tumor xenografts in mice. Overall, our results showed how the proteolytic state of EphA2 in tumors determines its effector function and influences its status as a candidate biomarker for targeted therapy. PMID:26130649

  4. Proteolysis of EphA2 Converts It from a Tumor Suppressor to an Oncoprotein.

    PubMed

    Koshikawa, Naohiko; Hoshino, Daisuke; Taniguchi, Hiroaki; Minegishi, Tomoko; Tomari, Taizo; Nam, Sung-Ouk; Aoki, Mikiko; Sueta, Takayuki; Nakagawa, Takashi; Miyamoto, Shingo; Nabeshima, Kazuki; Weaver, Alissa M; Seiki, Motoharu

    2015-08-15

    Eph receptor tyrosine kinases are considered candidate therapeutic targets in cancer, but they can exert opposing effects on cell growth. In the presence of its ligands, Eph receptor EphA2 suppresses signaling by other growth factor receptors, including ErbB, whereas ligand-independent activation of EphA2 augments ErbB signaling. To deploy EphA2-targeting drugs effectively in tumors, the anti-oncogenic ligand-dependent activation state of EphA2 must be discriminated from its oncogenic ligand-independent state. Because the molecular basis for the latter is little understood, we investigated how the activation state of EphA2 can be switched in tumor tissue. We found that ligand-binding domain of EphA2 is cleaved frequently by the membrane metalloproteinase MT1-MMP, a powerful modulator of the pericellular environment in tumor cells. EphA2 immunostaining revealed a significant loss of the N-terminal portion of EphA2 in areas of tumor tissue that expressed MT1-MMP. Moreover, EphA2 phosphorylation patterns that signify ligand-independent activation were observed specifically in these areas of tumor tissue. Mechanistic experiments revealed that processing of EphA2 by MT1-MMP promoted ErbB signaling, anchorage-independent growth, and cell migration. Conversely, expression of a proteolysis-resistant mutant of EphA2 prevented tumorigenesis and metastasis of human tumor xenografts in mice. Overall, our results showed how the proteolytic state of EphA2 in tumors determines its effector function and influences its status as a candidate biomarker for targeted therapy. ©2015 American Association for Cancer Research.

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

    PubMed

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

    2016-08-08

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

  6. The EphA2 receptor drives self-renewal and tumorigenicity in stem-like tumor-propagating cells from human glioblastomas.

    PubMed

    Binda, Elena; Visioli, Alberto; Giani, Fabrizio; Lamorte, Giuseppe; Copetti, Massimiliano; Pitter, Ken L; Huse, Jason T; Cajola, Laura; Zanetti, Nadia; DiMeco, Francesco; De Filippis, Lidia; Mangiola, Annunziato; Maira, Giulio; Anile, Carmelo; De Bonis, Pasquale; Reynolds, Brent A; Pasquale, Elena B; Vescovi, Angelo L

    2012-12-11

    In human glioblastomas (hGBMs), tumor-propagating cells with stem-like characteristics (TPCs) represent a key therapeutic target. We found that the EphA2 receptor tyrosine kinase is overexpressed in hGBM TPCs. Cytofluorimetric sorting into EphA2(High) and EphA2(Low) populations demonstrated that EphA2 expression correlates with the size and tumor-propagating ability of the TPC pool in hGBMs. Both ephrinA1-Fc, which caused EphA2 downregulation in TPCs, and siRNA-mediated knockdown of EPHA2 expression suppressed TPCs self-renewal ex vivo and intracranial tumorigenicity, pointing to EphA2 downregulation as a causal event in the loss of TPCs tumorigenicity. Infusion of ephrinA1-Fc into intracranial xenografts elicited strong tumor-suppressing effects, suggestive of therapeutic applications. Copyright © 2012 Elsevier Inc. All rights reserved.

  7. The EphA2 Receptor Drives Self-Renewal and Tumorigenicity in Stem-Like Tumor-Propagating Cells from Human Glioblastomas

    PubMed Central

    Binda, Elena; Visioli, Alberto; Giani, Fabrizio; Lamorte, Giuseppe; Copetti, Massimiliano; Pitter, Ken L.; Huse, Jason T.; Cajola, Laura; Zanetti, Nadia; DiMeco, Francesco; De Filippis, Lidia; Mangiola, Annunziato; Maira, Giulio; Anile, Carmelo; De Bonis, Pasquale; Reynolds, Brent A.; Pasquale, Elena B.; Vescovi, Angelo L.

    2014-01-01

    SUMMARY In human glioblastomas (hGBMs), tumor-propagating cells with stem-like characteristics (TPCs) represent a key therapeutic target. We found that the EphA2 receptor tyrosine kinase is overexpressed in hGBM TPCs. Cytofluorimetric sorting into EphA2High and EphA2Low populations demonstrated that EphA2 expression correlates with the size and tumor-propagating ability of the TPC pool in hGBMs. Both, ephrinA1-Fc, which caused EphA2 downregulation in TPCs, and siRNA-mediated knockdown of EPHA2 expression suppressed TPCs self-renewal ex vivo and intracranial tumorigenicity, pointing to EphA2 downregulation as a causal event in the loss of TPCs tumorigenicity. Infusion of ephrinA1-Fc into intracranial xenografts elicited strong tumor-suppressing effects, suggestive of therapeutic applications. PMID:23238013

  8. Mitosis-Mediated Intravasation in a Tissue-Engineered Tumor-Microvessel Platform.

    PubMed

    Wong, Andrew D; Searson, Peter C

    2017-11-15

    Intravasation involves the migration of tumor cells across the local endothelium and escape into vessel flow. Although tumor cell invasiveness has been correlated to increased intravasation, the details of transendothelial migration and detachment into circulation are still unclear. Here, we analyzed the intravasation of invasive human breast cancer cells within a tissue-engineered microvessel model of the tumor microenvironment. Using live-cell fluorescence microscopy, we captured 2,330 hours of tumor cell interactions with functional microvessels and provide evidence for a mitosis-mediated mechanism where tumor cells located along the vessel periphery are able to disrupt the vessel endothelium through cell division and detach into circulation. This model provides a framework for understanding the physical and biological parameters of the tumor microenvironment that mediate intravasation of tumor cells across an intact endothelium. Cancer Res; 77(22); 6453-61. ©2017 AACR . ©2017 American Association for Cancer Research.

  9. Enhancement in specific CD8+ T cell recognition of EphA2+ tumors in vitro and in vivo after treatment with ligand agonists.

    PubMed

    Wesa, Amy K; Herrem, Christopher J; Mandic, Maja; Taylor, Jennifer L; Vasquez, Cecilia; Kawabe, Mayumi; Tatsumi, Tomohide; Leibowitz, Michael S; Finke, James H; Bukowski, Ronald M; Bruckheimer, Elizabeth; Kinch, Michael S; Storkus, Walter J

    2008-12-01

    The EphA2 receptor tyrosine kinase is an attractive therapeutic target that is commonly overexpressed on solid tumors, with the degree of overexpression associated with disease progression, metastatic potential, and poor prognosis. Agonistic mAbs or ligand (ephrinA1)-Fc fusion protein are capable of inducing EphA2 internalization and degradation, thereby (at least transiently) eliminating the influence of this oncoprotein. We and others have also shown that EphA2 contains multiple peptide epitopes that can be recognized by effector CD4(+) and CD8(+) T cells isolated from tumor-bearing patients. Herein, we show that "agonist" reagents that trigger the proteasome-dependent degradation of tumor cell EphA2 result in the improved presentation of peptides derived from (both the extracellular and intracellular domains of) EphA2 in MHC class I complexes expressed on the tumor cell membrane for at least 48 h, as manifested by increased recognition by EphA2-specific CD8(+) T cells in vitro. We also observed that while delivery of ephrinA1-Fc fusion protein or agonist mAb into EphA2(+) tumor lesions promotes EphA2 degradation in situ, this single administration of agent does not dramatically alter tumor progression in a humanized SCID model. However, when combined with the adoptive transfer of normally nontherapeutic (human) anti-EphA2 CD8(+) CTL, this dual-agent regimen results in complete tumor eradication. These results suggest that strategies targeting the conditional proteasome-mediated destruction of tumor cell EphA2 may enable EphA2-specific CD8(+) T cells (of modest functional avidity) to realize improved therapeutic potential.

  10. Enhancement in Specific CD8+ T cell Recognition of EphA2+ Tumors In Vitro and In Vivo After Treatment with Ligand Agonists1

    PubMed Central

    Wesa, Amy K.; Herrem, Christopher J.; Mandic, Maja; Taylor, Jennifer L.; Vasquez, Cecilia; Kawabe, Mayumi; Tatsumi, Tomohide; Leibowitz, Michael S.; Finke, James H.; Bukowski, Ronald M.; Bruckheimer, Elizabeth; Kinch, Michael S.; Storkus, Walter J.

    2012-01-01

    The EphA2 receptor tyrosine kinase (RTK) is an attractive therapeutic target that is commonly overexpressed on solid tumors, with the degree of overexpression associated with disease progression, metastatic potential and poor prognosis. Agonistic monoclonal antibodies or ligand (ephrinA1)-Fc fusion protein are capable of inducing EphA2 internalization and degradation, thereby (at least transiently) eliminating the influence of this oncoprotein. We and others have also shown that EphA2 contains multiple peptide epitopes that can be recognized by effector CD4+ and CD8+ T cells isolated from tumor-bearing patients. Herein, we show that “agonist” reagents that trigger the proteasome-dependent degradation of tumor cell EphA2 result in the improved presentation of peptides derived from (both the extracellular and intracellular domains of) EphA2 in MHC class I complexes expressed on the tumor cell membrane for at least 48h, as manifest by increased recognition by EphA2-specific CD8+ T cells in vitro. We also observed that while delivery of ephrinA1-Fc fusion protein or agonist mAb into EphA2+ tumor lesions promotes EphA2 degradation in situ, this single administration of agent does not dramatically alter tumor progression in a Hu-SCID model. However, when combined with the adoptive transfer of normally non-therapeutic (human) anti-EphA2 CD8+ cytotoxic T lymphocytes (CTL), this dual agent regimen results in complete tumor eradication. These results suggest that strategies targeting the conditional proteasome-mediated destruction of tumor cell EphA2 may enable EphA2-specific CD8+ T cells (of modest functional avidity) to realize improved therapeutic potential. PMID:19017961

  11. Tumor-Mediated Suppression of Dendritic Cell Vaccines

    DTIC Science & Technology

    2005-03-01

    In another study by our group [42] using a poorly immunogenic, highly aggressive and metastatic mouse mammary tumor cell line (4T1), we... Drosophila melanogaster . Genetics 1995; 139:1347-58. [25] Savage C, Das P, Finelli AL, Townsend SR, Sun CY, Baird SE, et al. Caenorhabditis elegans...candidates for cancer immunotherapy. A number of tumor-derived products have been suggested to promote tumor establishment and progression by interfering

  12. Cathepsin S-mediated autophagic flux in tumor-associated macrophages accelerate tumor development by promoting M2 polarization

    PubMed Central

    2014-01-01

    Background Tumor-associated macrophages (TAMs) are the major component of tumor-infiltrating leukocytes. TAMs are heterogeneous, with distinct phenotypes influenced by the microenvironment surrounding tumor tissues, but relatively little is known about the key molecular in these cells that contribute to malignant phenotypes. Autophagic activity is a critical factor in tumor development that contributes to enhancing cellular fitness and survival in the hostile tumor microenvironment. However, the molecular basis and relations between autophagy and TAMs polarization remain unclear. Methods Cathepsin S (Cat S) expression was analyzed in human colon carcinoma and normal colon tissues. In vivo effects were evaluated using PancO2 subcutaneous tumor model and SL4 hepatic metastasis model. Immunofluorescence staining, flow cytometry and real-time PCR were done to examine TAMs polarization. Western blotting assay, transmission electron microscopy, mCherry-GFP-LC3 transfection and DQ-BSA degradation assays were carried out to determine its role in regulating autophagy. Results In the present study, we showed that the enhanced expression of Cat S correlated with the severity of histologic grade as well as clinical stage, metastasis, and recurrence, which are known indicators of a relatively poor prognosis of human colon carcinoma. Cat S knockout led to decreased tumor growth and metastasis. Moreover, Cat S knockout inhibited M2 macrophage polarization during tumor development. We further demonstrated that Cat S was required for not only autophagic flux but also the fusion processes of autophagosomes and lysosomes in TAMs. Importantly, we found that Cat S contributed to tumor development by regulating the M2 phenotype of TAMs through the activation of autophagy. Conclusions These results indicated that Cat S-mediated autophagic flux is an important mechanism for inducing M2-type polarization of TAMs, which leads to tumor development. These data provide strong evidence for a

  13. Real-time noninvasive optoacoustic monitoring of nanoparticle-mediated photothermal therapy of tumors

    NASA Astrophysics Data System (ADS)

    Esenaliev, R. O.; Petrov, Y. Y.; Cicenaite, I.; Chumakova, O. V.; Petrova, I. Y.; Patrikeev, I.; Liopo, A.

    2007-02-01

    We proposed and have been developing real-time, noninvasive monitoring of blood oxygenation, total hemoglobin concentration, and thermotherapy including hyperthermia, coagulation, and cryotherapy. In this paper we propose to use the optoacoustic technique for monitoring of nanoparticle-mediated photothermal therapy (NPT) of tumors. NPT is based on heating exogenous strongly-absorbing nanoparticles selectively delivered in tumors. Real-time monitoring of NPT is necessary for precise tumor therapy with minimal damage to normal tissues. In this study we injected PEGylated and non-PEGylated carbon nanoparticles in nude mice bearing human tumors (5-15 mm) and irradiated the tumors for 10 minutes with nanosecond Nd:YAG laser pulses which produced both thermal damage to the tumors and optoacoustic signals for monitoring NPT in real time. Irradiation of tumors was performed during or after (3 or 24 hours) nanoparticle injection. Amplitude and temporal parameters of optoacoustic signals (measured with a custom-made wide-band optoacoustic probe) correlated well with nanoparticle injection, temperature rise in tumors, and tumor coagulation. Substantial thermal damage in large areas of the tumors was produced when optimal irradiation parameters were used. Monte Carlo modeling of light distribution in tumors and optoacoustic theory were applied to study kinetics of nanoparticle concentration in the tumors. Our results demonstrated that the optoacoustic technique can be used for real-time monitoring of NTP and provide precise tumor therapy with minimal damage to normal tissues.

  14. Inflammatory cytokine-mediated evasion of virus-induced tumors from NK cell control.

    PubMed

    Mishra, Rabinarayan; Polic, Bojan; Welsh, Raymond M; Szomolanyi-Tsuda, Eva

    2013-07-15

    Infections with DNA tumor viruses, including members of the polyomavirus family, often result in tumor formation in immune-deficient hosts. The complex control involved in antiviral and antitumor immune responses during these infections can be studied in murine polyomavirus (PyV)-infected mice as a model. We found that NK cells efficiently kill cells derived from PyV-induced salivary gland tumors in vitro in an NKG2D (effector cell)-RAE-1 (target cell)-dependent manner; but in T cell-deficient mice, NK cells only delay but do not prevent the development of PyV-induced tumors. In this article, we show that the PyV-induced tumors have infiltrating functional NK cells. The freshly removed tumors, however, lack surface RAE-1 expression, and the tumor tissues produce soluble factors that downregulate RAE-1. These factors include the proinflammatory cytokines IL-1α, IL-1β, IL-33, and TNF. Each of these cytokines downregulates RAE-1 expression and susceptibility to NK cell-mediated cytotoxicity. CD11b(+)F4/80(+) macrophages infiltrating the PyV-induced tumors produce high amounts of IL-1β and TNF. Thus, our data suggest a new mechanism whereby inflammatory cytokines generated in the tumor environment lead to evasion of NK cell-mediated control of virus-induced tumors.

  15. Cutting edge: granzymes A and B are not essential for perforin-mediated tumor rejection.

    PubMed

    Smyth, Mark J; Street, Shayna E A; Trapani, Joseph A

    2003-07-15

    Controversy still exists regarding the biological function of granzyme serine proteases released with perforin from the cytotoxic granules of NK cells and CTLs. In particular, it is not clear whether the major granzymes, A and B, play an essential role in tumor rejection mediated by the perforin pathway. We have now examined the relative importance of perforin and granzyme A and B clusters in five different tumor models that stringently distinguish their importance. We conclude that granzyme A and B clusters are not essential for CTL- and NK cell-mediated rejection of spontaneous and experimental tumors, raising the likelihood that either perforin alone or in combination with an additional granzyme or granule component(s) mediates cytotoxicity of tumor cells in vivo.

  16. Use of gold nanoshells to mediate heating induced perfusion changes in prostate tumors

    NASA Astrophysics Data System (ADS)

    Shetty, Anil; Elliott, Andrew M.; Schwartz, Jon A.; Wang, James; Esparza-Coss, Emilio; Klumpp, Sherry; Taylor, Brian; Hazle, John D.; Stafford, R. Jason

    2008-02-01

    This study investigates the potential of using gold nanoshells to mediate a thermally induced modulation of tumor vasculature in experimental prostate tumors. We demonstrate that after passive extravasation and retention of the circulating nanoshells from the tumor vasculature into the tumor interstitium, the enhanced nanoshells absorption of near-infrared irradiation over normal vasculature, can be used to increase tumor perfusion or shut it down at powers which result in no observable affects on tissue without nanoshells. Temperature rise was monitored in real time using magnetic resonance temperature imaging and registered with perfusion changes as extrapolated from MR dynamic contrast enhanced (DCE) imaging results before and after each treatment. Results indicate that nanoshell mediated heating can be used to improve perfusion and subsequently enhance drug delivery and radiation effects, or be used to shut down perfusion to assist in thermal ablative therapy delivery.

  17. Ablation of EIF5A2 induces tumor vasculature remodeling and improves tumor response to chemotherapy via regulation of matrix metalloproteinase 2 expression.

    PubMed

    Wang, Feng-Wei; Cai, Mu-Yan; Mai, Shi-Juan; Chen, Jie-Wei; Bai, Hai-Yan; Li, Yan; Liao, Yi-Ji; Li, Chang-Peng; Tian, Xiao-Peng; Kung, Hsiang-Fu; Guan, Xin-Yuan; Xie, Dan

    2014-08-30

    Hepatocellular carcinoma (HCC) is a highly vascularized tumor with poor clinical outcome. Our previous work has shown that eukaryotic initiation factor 5A2 (EIF5A2) over-expression enhances HCC cell metastasis. In this study, EIF5A2 was identified to be an independent risk factor for poor disease-specific survival among HCC patients. Both in vitro and in vivo assays indicated that ablation of endogenous EIF5A2 inhibited tumor angiogenesis by reducing matrix metalloproteinase 2 (MMP-2) expression. Given that MMP-2 degrades collagen IV, a main component of the vascular basement membrane (BM), we subsequently investigated the effect of EIF5A2 on tumor vasculature remodeling using complementary approaches, including fluorescent immunostaining, transmission electron microscopy, tumor perfusion assays and tumor hypoxia assays. Taken together, our results indicate that EIF5A2 silencing increases tumor vessel wall continuity, increases blood perfusion and improves tumor oxygenation. Additionally, we found that ablation of EIF5A2 enhanced the chemosensitivity of HCC cells to 5-Fluorouracil (5-FU). Finally, we demonstrated that EIF5A2 might exert these functions by enhancing MMP-2 activity via activation of p38 MAPK and JNK/c-Jun pathways. This study highlights an important role of EIF5A2 in HCC tumor vessel remodeling and indicates that EIF5A2 represents a potential therapeutic target in the treatment of HCC.

  18. NK Cells and γδ T Cells Mediate Resistance to Polyomavirus–Induced Tumors

    PubMed Central

    Mishra, Rabinarayan; Chen, Alex T.; Welsh, Raymond M.; Szomolanyi-Tsuda, Eva

    2010-01-01

    NK and γδ T cells can eliminate tumor cells in many experimental models, but their effect on the development of tumors caused by virus infections in vivo is not known. Polyomavirus (PyV) induces tumors in neonatally infected mice of susceptible strains and in adult mice with certain immune deficiencies, and CD8+ αβ T cells are regarded as the main effectors in anti-tumor immunity. Here we report that adult TCRβ knockout (KO) mice that lack αβ but have γδ T cells remain tumor-free after PyV infection, whereas TCRβ×δ KO mice that lack all T cells develop tumors. In addition, E26 mice, which lack NK and T cells, develop the tumors earlier than TCRβ×δ KO mice. These observations implicate γδ T and NK cells in the resistance to PyV-induced tumors. Cell lines established from PyV-induced tumors activate NK and γδ T cells both in culture and in vivo and express Rae-1, an NKG2D ligand. Moreover, these PyV tumor cells are killed by NK cells in vitro, and this cytotoxicity is prevented by treatment with NKG2D-blocking antibodies. Our findings demonstrate a protective role for NK and γδ T cells against naturally occurring virus-induced tumors and suggest the involvement of NKG2D-mediated mechanisms. PMID:20523894

  19. Three-Dimensional Scaffolds to Evaluate Tumor Associated Fibroblast-Mediated Suppression of Breast Tumor Specific T Cells

    PubMed Central

    Phan-Lai, Vy; Florczyk, Stephen J.; Kievit, Forrest M.; Wang, Kui; Gad, Ekram; Disis, Nora L.; Zhang, Miqin

    2013-01-01

    In the tumor microenvironment, the signals from tumor-associated fibroblasts (TAF) that suppress antitumor immunity remain unclear. Here, we develop and investigate an in vitro three-dimensional (3D) scaffold model for the novel evaluation of TAF interaction with breast tumor cells and breast specific, neu antigen (p98) reactive T cells. Breast cancer cells seeded on 3D chitosan-alginate (CA) scaffolds showed productive growth and formed distinct tumor spheroids. Antigen specific p98 T cells, but not naïve T cells, bound significantly better to tumor cells on scaffolds. The p98 T cells induced potent tumor cell killing but T helper cell cytokine function was impaired in the presence of TAF co-seeding on scaffolds. We found that the immunosuppression was mediated, in part, by transforming growth factor beta (TGF-b) and interleukin-10 (IL-10). Therefore TAF appear capable of inducing potent T cell suppression. CA scaffolds can provide clinically relevant findings prior to preclinical testing of novel immunotherapies. PMID:23517456

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

    NASA Technical Reports Server (NTRS)

    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.

  1. Magnesium improves cisplatin-mediated tumor killing while protecting against cisplatin-induced nephrotoxicity.

    PubMed

    Kumar, Gopal; Solanki, Malvika H; Xue, Xiangying; Mintz, Rachel; Madankumar, Swati; Chatterjee, Prodyot K; Metz, Christine N

    2017-08-01

    Approximately 30% of all cancer patients treated with cisplatin, a widely used broad-spectrum chemotherapeutic agent, experience acute kidney injury (AKI). Almost all patients receiving cisplatin have magnesium (Mg) losses, which are proposed to aggravate AKI. Currently, there are no methods to successfully treat or prevent cisplatin-AKI. Whereas Mg supplementation has been shown to reduce AKI in experimental models and several small clinical trials, the effects of Mg status on tumor outcomes in immunocompetent tumor-bearing mice and humans have not been investigated. The purpose of this study was to further examine the effects of Mg deficiency (±Mg supplementation) on cisplatin-mediated AKI and tumor killing in immunocompetent mice bearing CT26 colon tumors. Using a model where cisplatin alone (20 mg/kg cumulative dose) produced minimal kidney injury, Mg deficiency significantly worsened cisplatin-mediated AKI, as determined by biochemical markers (blood urea nitrogen and plasma creatinine) and histological renal changes, as well as markers of renal oxidative stress, inflammation, and apoptosis. By contrast, Mg supplementation blocked cisplatin-induced kidney injury. Using LLC-PK 1 renal epithelial cells, we observed that Mg deficiency or inhibition of Mg uptake significantly enhanced cisplatin-induced cytotoxicity, whereas Mg supplementation protected against cytotoxicity. However, neither Mg deficiency nor inhibition of Mg uptake impaired cisplatin-mediated killing of CT26 tumor cells in vitro. Mg deficiency was associated with significantly larger CT26 tumors in BALB/c mice when compared with normal-fed control mice, and Mg deficiency significantly reduced cisplatin-mediated tumor killing in vivo. Finally, Mg supplementation did not compromise cisplatin's anti-tumor efficacy in vivo. Copyright © 2017 the American Physiological Society.

  2. Genes Encoding Phospholipases A2 Mediate Insect Nodulation Reactions to Bacterial Challenge

    USDA-ARS?s Scientific Manuscript database

    We propose that expression of four genes encoding secretory phospholipases A2 (sPLA2) mediates insect nodulation responses to bacterial infection. Nodulation is the quantitatively predominant cellular defense reaction to bacterial infection. This reaction is mediated by eicosanoids, the biosynthesis...

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

    DTIC Science & Technology

    2005-02-01

    Craig A. Hauser , Ph.D. Gabriele Foos, Ph.D. CONTRACTING ORGANIZATION: The Burnham Institute La Jolla, California 92037 REPORT DATE: February 2005 TYPE...NUMBERS Gene Targets in Prostate Tumor Cells that Mediate DAMD17-02-1-0019 Aberrant Growth and Invasiveness 6. AUTHOR(S) Craig A. Hauser , Ph.D. Gabriele...REPORTABLE OUTCOMES Foos G, Hauser CA (2004) The role of Ets transcription factors in mediating cellular transformation. In: Handbook of Experimental

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

    PubMed Central

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

    2016-01-01

    ABSTARCT Bacteria-mediated tumor therapy using Salmonella enterica serovar Typhimurium is a therapeutic option with great potential. Numerous studies explored the potential of Salmonella Typhimurium for therapeutic applications, however reconciling safety with vectorial efficacy remains a major issue. Recently we have described a conditionally attenuated Salmonella vector that is based on genetic lipopolysaccharide modification. This vector combines strong attenuation with appropriate anti-tumor properties by targeting various cancerous tissues in vivo. Therefore, it was promoted as an anti-tumor agent. In this addendum, we summarize these findings and demonstrate additional optimization steps that may further improve the therapeutic efficacy of our vector strain. PMID:26939530

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

    PubMed

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

    2007-12-01

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

  6. Interleukin-1 is required for cancer eradication mediated by tumor-specific Th1 cells.

    PubMed

    Haabeth, Ole Audun Werner; Lorvik, Kristina Berg; Yagita, Hideo; Bogen, Bjarne; Corthay, Alexandre

    The role of inflammation in cancer is controversial as both tumor-promoting and tumor-suppressive aspects of inflammation have been reported. In particular, it has been shown that pro-inflammatory cytokines, like interleukin-1α (IL-1α), IL-1β, IL-6, and tumor necrosis factor α (TNFα), may either promote or suppress cancer. However, the cellular and molecular basis underlying these opposing outcomes remains enigmatic. Using mouse models for myeloma and lymphoma, we have recently reported that inflammation driven by tumor-specific T helper 1 (Th1) cells conferred protection against B-cell cancer and that interferon-γ (IFN-γ) was essential for this process. Here, we have investigated the contribution of several inflammatory mediators. Myeloma eradication by Th1 cells was not affected by inhibition of TNF-α, TNF-related weak inducer of apoptosis (TWEAK), or TNF-related apoptosis-inducing ligand (TRAIL). In contrast, cancer elimination by tumor-specific Th1 cells was severely impaired by the in vivo neutralization of both IL-1α and IL-1β (collectively named IL-1) with IL-1 receptor antagonist (IL-1Ra). The antitumor functions of tumor-specific Th1 cells and tumor-infiltrating macrophages were both affected by IL-1 neutralization. Secretion of the Th1-derived cytokines IL-2 and IFN-γ at the incipient tumor site was severely reduced by IL-1 blockade. Moreover, IL-1 was shown to synergize with IFN-γ for induction of tumoricidal activity in tumor-infiltrating macrophages. This synergy between IL-1 and IFN-γ may explain how inflammation, when driven by tumor-specific Th1 cells, represses rather than promotes cancer. Collectively, the data reveal a central role of inflammation, and more specifically of the canonical pro-inflammatory cytokine IL-1, in enhancing Th1-mediated immunity against cancer.

  7. Macrophages mediate a switch between canonical and non-canonical Wnt pathways in canine mammary tumors.

    PubMed

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

    2014-01-01

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

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

    PubMed Central

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

    2014-01-01

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

  9. Size Dependent Kinetics of Gold Nanorods in EPR Mediated Tumor Delivery

    PubMed Central

    Tong, Xiao; Wang, Zhantong; Sun, Xiaolian; Song, Jibin; Jacobson, Orit; Niu, Gang; Kiesewetter, Dale O.; Chen, Xiaoyuan

    2016-01-01

    Gold nanorods (AuNR) have been intensively used in nanomedicine for cancer diagnostics and therapy, due to their excellent plasmonic photothermal properties. Tuning the size and aspect ratio of AuNR tailors the localized surface plasmon resonance (LSPR) in the NIR spectrum at which biological tissues are transparent, thus enables specific and effective treatment. The AuNR extravasates into tumor interstitium through enhanced permeation and retention (EPR) effect. Efficient AuNR based cancer therapy requires efficient AuNR tumor delivery. However, the size of AuNR can dramatically affect its blood circulation and tumor accumulation. Here we proposed for the first time a systematic framework to investigate the size-dependent kinetics of AuNRs during EPR mediated tumor delivery. By using 64Cu-labeled AuNRs with positron emission tomography (PET) and kinetic modeling, the in vivo uptake and kinetics of 64Cu-AuNR during its blood circulation, tumor accumulation and elimination were studied both in vitro and in vivo. The results of different sized AuNRs were compared and the optimum size of AuNR was suggested for EPR mediated tumor delivery. Our study provides a better understanding of the in vivo behavior of AuNR, which can help future design of nanomaterials for cancer imaging and therapy. PMID:27698939

  10. Nanoparticle-Mediated Photothermal Therapy of Brain Tumors

    NASA Astrophysics Data System (ADS)

    Makkouk, Amani R.; Madsen, Steen J.

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

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

    NASA Astrophysics Data System (ADS)

    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

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

    NASA Astrophysics Data System (ADS)

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

    2017-01-01

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

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

    PubMed Central

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

    2006-01-01

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

  14. The ephrin-A1 ligand and its receptor, EphA2, are expressed during tumor neovascularization.

    PubMed

    Ogawa, K; Pasqualini, R; Lindberg, R A; Kain, R; Freeman, A L; Pasquale, E B

    2000-12-07

    Eph receptor tyrosine kinases and their ephrin ligands have been implicated in embryonic vascular development and in in vivo models of angiogenesis. Eph proteins may also regulate tumor neovascularization, but this role has not been previously investigated. To screen for Eph proteins expressed in tumor blood vessels, we used tumor xenografts grown in nude mice from MDA-MB-435 human breast cancer cells or KS1767 human Kaposi's sarcoma cells. By immunohistochemistry, the ephrin-A1 ligand and one of its receptors, EphA2, were detected throughout tumor vasculature. Double-labeling with anti-CD34 antibodies demonstrated that both ephrin-A1 and EphA2 were expressed in xenograft endothelial cells and also tumor cells. Furthermore, EphA2 was tyrosine-phosphorylated in the xenograft tumors, indicating that it was activated, presumably by interacting with ephrin-A1. Ephrin-A1 and EphA2 were also detected in both the vasculature and tumor cells of surgically removed human cancers. In an in vitro angiogenesis model, a dominant negative form of EphA2 inhibited capillary tube-like formation by human umbilical vein endothelial cells (HUVECs), demonstrating a requirement for EphA receptor signaling. These data suggest that ephrin-A1 and EphA2 play a role in human cancers, at least in part by influencing tumor neovascularization. Eph proteins may represent promising new targets for antiangiogenic cancer treatments.

  15. Malignant astrocytic tumor progression potentiated by JAK-mediated recruitment of myeloid cells

    PubMed Central

    Rajappa, Prajwal; Cobb, William S.; Vartanian, Emma; Huang, Yujie; Daly, Laura; Hoffman, Caitlin; Zhang, Jane; Shen, Beiyi; Yanowitch, Rachel; Garg, Kunal; Cisse, Babacar; Haddock, Sara; Huse, Jason; Pisapia, David J.; Chan, Timothy A.; Lyden, David C.; Bromberg, Jacqueline F.; Greenfield., Jeffrey P.

    2017-01-01

    Purpose While the tumor microenvironment has been known to play an integral role in tumor progression, the function of non-resident bone marrow-derived cells (BMDCs) remains to be determined in neurological tumors. Here we identified the contribution of BMDC recruitment in mediating malignant transformation from low- to high-grade gliomas. Experimental Design We analyzed human blood and tumor samples from patients with low- and high-grade gliomas. A spontaneous platelet derived growth factor (PDGF) murine glioma model (RCAS) was utilized to recapitulate human disease progression. Levels of CD11b+/Gr1+ BMDCs were analyzed at discrete stages of tumor progression. Using bone marrow transplantation, we determined the unique influence of BMDCs in the transition from low- to high-grade glioma. The functional role of these BMDCs was then examined using a JAK 1/2 inhibitor (AZD1480). Results CD11b+ myeloid cells were significantly increased during tumor progression in peripheral blood and tumors of glioma patients. Increases in CD11b+/Gr1+ cells were observed in murine peripheral blood, bone marrow, and tumors during low-grade to high-grade transformation. Transient blockade of CD11b+ cell expansion using a JAK 1/2 Inhibitor (AZD1480) impaired mobilization of these cells and was associated with a reduction in tumor volume, maintenance of a low-grade tumor phenotype and prolongation in survival. Conclusion We demonstrate that impaired recruitment of CD11b+ myeloid cells with a JAK1/2 inhibitor inhibits glioma progression in vivo and prolongs survival in a murine glioma model. PMID:28039266

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

    NASA Astrophysics Data System (ADS)

    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.

  17. Phosphorylation of carbonic anhydrase IX controls its ability to mediate extracellular acidification in hypoxic tumors.

    PubMed

    Ditte, Peter; Dequiedt, Franck; Svastova, Eliska; Hulikova, Alzbeta; Ohradanova-Repic, Anna; Zatovicova, Miriam; Csaderova, Lucia; Kopacek, Juraj; Supuran, Claudiu T; Pastorekova, Silvia; Pastorek, Jaromir

    2011-12-15

    In the hypoxic regions of a tumor, carbonic anhydrase IX (CA IX) is an important transmembrane component of the pH regulatory machinery that participates in bicarbonate transport. Because tumor pH has implications for growth, invasion, and therapy, determining the basis for the contributions of CA IX to the hypoxic tumor microenvironment could lead to new fundamental and practical insights. Here, we report that Thr443 phosphorylation at the intracellular domain of CA IX by protein kinase A (PKA) is critical for its activation in hypoxic cells, with the fullest activity of CA IX also requiring dephosphorylation of Ser448. PKA is activated by cAMP, which is elevated by hypoxia, and we found that attenuating PKA in cells disrupted CA IX-mediated extracellular acidification. Moreover, following hypoxia induction, CA IX colocalized with the sodium-bicarbonate cotransporter and other PKA substrates in the leading edge membranes of migrating tumor cells, in support of the concept that bicarbonate metabolism is spatially regulated at cell surface sites with high local ion transport and pH control. Using chimeric CA IX proteins containing heterologous catalytic domains derived from related CA enzymes, we showed that CA IX activity was modulated chiefly by the intracellular domain where Thr443 is located. Our findings indicate that CA IX is a pivotal mediator of the hypoxia-cAMP-PKA axis, which regulates pH in the hypoxic tumor microenvironment.

  18. EphA2-mediated mesenchymal-amoeboid transition induced by endothelial progenitor cells enhances metastatic spread due to cancer-associated fibroblasts.

    PubMed

    Giannoni, Elisa; Taddei, Maria Letizia; Parri, Matteo; Bianchini, Francesca; Santosuosso, Michela; Grifantini, Renata; Fibbi, Gabriella; Mazzanti, Benedetta; Calorini, Lido; Chiarugi, Paola

    2013-01-01

    Tumor progression is deeply influenced by epigenetic changes induced by tumor stroma. Cancer-associated fibroblasts (CAFs) have been reported to promote epithelial-mesenchymal transition in cancer cells, thereby enhancing their aggressiveness and stem-like properties. As CAFs are able to recruit endothelial progenitor cells (EPCs) to tumor site, we aim to investigate their interplay for prostate carcinoma progression. Both prostate CAFs and cancer cells actively recruit EPCs, known to affect tumor progression through increased vasculogenesis. EPCs synergize with CAFs to further promote epigenetic plasticity of cancer cells, through a mesenchymal-to-amoeboid transition. Indeed, after fibroblasts have engaged epithelial-mesenchymal transition in cancer cells, a further shift towards amoeboid motility is promoted by EPCs through contact-mediated triggering of the bidirectional ephrinA1/EphA2 signaling. The activation of ephrinA1 reverse pathway enhances EPC-induced neo-vascularization, thus promoting tumor growth, while EphA2 forward signaling elicits mesenchymal-amoeboid transition in cancer cells, favoring their adhesion to endothelium, transendothelial migration, and lung metastatic colonization. We therefore underscore that the metastatic advantage given by tumor microenvironment embraces different motility strategies and propose EphA2-targeted tools as useful adjuvants in anti-metastatic treatments.

  19. Systems Pharmacological Analysis of Paclitaxel-Mediated Tumor Priming That Enhances Nanocarrier Deposition and Efficacy

    PubMed Central

    Straubinger, Robert M.; Mager, Donald E.

    2013-01-01

    Paclitaxel (PAC)-mediated apoptosis decompresses and primes tumors for enhanced deposition of nanoparticulate agents such as pegylated liposomal doxorubicin (DXR). A quantitative pharmacokinetic/pharmacodynamic (PK/PD) approach was developed to analyze efficacy and identify optima for PAC combined with sterically stabilized liposome (SSL)-DXR. Using data extracted from diverse literature sources, Cremophor-paclitaxel (Taxol®) PK was described by a carrier-mediated dispositional model and SSL-DXR PK was described by a two-compartment model with first-order drug release. A hybrid-physiologic, well-stirred model with partition coefficients (Kp) captured intratumor concentrations. Apoptotic responses driving tumor priming were modeled using nonlinear, time-dependent transduction functions. The tumor growth model used net first-order growth and death rate constants, and two transit compartments that captured the temporal displacement of tumor exposure versus effect, and apoptotic signals from each agent were used to drive cytotoxic effects of the combination. The final model captured plasma and intratumor PK data, apoptosis induction profiles, and tumor growth for all treatments/sequences. A feedback loop representing PAC-induced apoptosis effects on Kp_DXR enabled the model to capture tumor-priming effects. Simulations to explore time- and sequence-dependent effects of priming indicated that PAC priming increased Kp_DXR 3-fold. The intratumor concentrations producing maximal and half-maximal effects were 18 and 7.2 μg/ml for PAC, and 17.6 and 14.3 μg/ml for SSL-DXR. The duration of drug-induced apoptosis was 27.4 h for PAC and 15.8 h for SSL-DXR. Simulations suggested that PAC administered 24 h before peak priming could increase efficacy 2.5-fold over experimentally reported results. The quantitative approach developed in this article is applicable for evaluating tumor-priming strategies using diverse agents. PMID:23115220

  20. Disruption of CXCR2-mediated MDSC tumor trafficking enhances anti-PD1 efficacy.

    PubMed

    Highfill, Steven L; Cui, Yongzhi; Giles, Amber J; Smith, Jillian P; Zhang, Hua; Morse, Elizabeth; Kaplan, Rosandra N; Mackall, Crystal L

    2014-05-21

    Suppression of the host's immune system plays a major role in cancer progression. Tumor signaling of programmed death 1 (PD1) on T cells and expansion of myeloid-derived suppressor cells (MDSCs) are major mechanisms of tumor immune escape. We sought to target these pathways in rhabdomyosarcoma (RMS), the most common soft tissue sarcoma of childhood. Murine RMS showed high surface expression of PD-L1, and anti-PD1 prevented tumor growth if initiated early after tumor inoculation; however, delayed anti-PD1 had limited benefit. RMS induced robust expansion of CXCR2(+)CD11b(+)Ly6G(hi) MDSCs, and CXCR2 deficiency prevented CD11b(+)Ly6G(hi) MDSC trafficking to the tumor. When tumor trafficking of MDSCs was inhibited by CXCR2 deficiency, or after anti-CXCR2 monoclonal antibody therapy, delayed anti-PD1 treatment induced significant antitumor effects. Thus, CXCR2(+)CD11b(+)Ly6G(hi) MDSCs mediate local immunosuppression, which limits the efficacy of checkpoint blockade in murine RMS. Human pediatric sarcomas also produce CXCR2 ligands, including CXCL8. Patients with metastatic pediatric sarcomas display elevated serum CXCR2 ligands, and elevated CXCL8 is associated with diminished survival in this population. We conclude that accumulation of MDSCs in the tumor bed limits the efficacy of checkpoint blockade in cancer. We also identify CXCR2 as a novel target for modulating tumor immune escape and present evidence that CXCR2(+)CD11b(+)Ly6G(hi) MDSCs are an important suppressive myeloid subset in pediatric sarcomas. These findings present a translatable strategy to improve the efficacy of checkpoint blockade by preventing trafficking of MDSCs to the tumor site. Copyright © 2014, American Association for the Advancement of Science.

  1. Granzyme B and perforin are important for regulatory T cell-mediated suppression of tumor clearance.

    PubMed

    Cao, Xuefang; Cai, Sheng F; Fehniger, Todd A; Song, Jiling; Collins, Lynne I; Piwnica-Worms, David R; Ley, Timothy J

    2007-10-01

    Granzyme B is important for the ability of NK cells and CD8(+) T cells to kill their targets. However, we showed here that granzyme B-deficient mice clear both allogeneic and syngeneic tumor cell lines more efficiently than do wild-type (WT) mice. To determine whether regulatory T (Treg) cells utilize granzyme B to suppress immune responses against these tumors, we examined the expression and function of granzyme B in Treg cells. Granzyme B was not expressed in naive Treg cells but was highly expressed in 5%-30% of CD4(+)Foxp3(+) Treg cells in the tumor environment. Adoptive transfer of WT Treg cells, but not granzyme B- or perforin-deficient Treg cells, into granzyme B-deficient mice partially restored susceptibility to tumor growth; Treg cells derived from the tumor environment could induce NK and CD8(+) T cell death in a granzyme B- and perforin-dependent fashion. Granzyme B and perforin are therefore relevant for Treg cell-mediated suppression of tumor clearance in vivo.

  2. GFAP-Cre-Mediated Transgenic Activation of Bmi1 Results in Pituitary Tumors

    PubMed Central

    Westerman, Bart A.; Blom, Marleen; Tanger, Ellen; van der Valk, Martin; Song, Ji-Ying; van Santen, Marije; Gadiot, Jules; Cornelissen-Steijger, Paulien; Zevenhoven, John; Prosser, Haydn M.; Uren, Anthony; Aronica, Eleonora; van Lohuizen, Maarten

    2012-01-01

    Bmi1 is a member of the polycomb repressive complex 1 and plays different roles during embryonic development, depending on the developmental context. Bmi1 over expression is observed in many types of cancer, including tumors of astroglial and neural origin. Although genetic depletion of Bmi1 has been described to result in tumor inhibitory effects partly through INK4A/Arf mediated senescence and apoptosis and also through INK4A/Arf independent effects, it has not been proven that Bmi1 can be causally involved in the formation of these tumors. To see whether this is the case, we developed two conditional Bmi1 transgenic models that were crossed with GFAP-Cre mice to activate transgenic expression in neural and glial lineages. We show here that these mice generate intermediate and anterior lobe pituitary tumors that are positive for ACTH and beta-endorphin. Combined transgenic expression of Bmi1 together with conditional loss of Rb resulted in pituitary tumors but was insufficient to induce medulloblastoma therefore indicating that the oncogenic function of Bmi1 depends on regulation of p16INK4A/Rb rather than on regulation of p19ARF/p53. Human pituitary adenomas show Bmi1 overexpression in over 50% of the cases, which indicates that Bmi1 could be causally involved in formation of these tumors similarly as in our mouse model. PMID:22574128

  3. GFAP-Cre-mediated transgenic activation of Bmi1 results in pituitary tumors.

    PubMed

    Westerman, Bart A; Blom, Marleen; Tanger, Ellen; van der Valk, Martin; Song, Ji-Ying; van Santen, Marije; Gadiot, Jules; Cornelissen-Steijger, Paulien; Zevenhoven, John; Prosser, Haydn M; Uren, Anthony; Aronica, Eleonora; van Lohuizen, Maarten

    2012-01-01

    Bmi1 is a member of the polycomb repressive complex 1 and plays different roles during embryonic development, depending on the developmental context. Bmi1 over expression is observed in many types of cancer, including tumors of astroglial and neural origin. Although genetic depletion of Bmi1 has been described to result in tumor inhibitory effects partly through INK4A/Arf mediated senescence and apoptosis and also through INK4A/Arf independent effects, it has not been proven that Bmi1 can be causally involved in the formation of these tumors. To see whether this is the case, we developed two conditional Bmi1 transgenic models that were crossed with GFAP-Cre mice to activate transgenic expression in neural and glial lineages. We show here that these mice generate intermediate and anterior lobe pituitary tumors that are positive for ACTH and beta-endorphin. Combined transgenic expression of Bmi1 together with conditional loss of Rb resulted in pituitary tumors but was insufficient to induce medulloblastoma therefore indicating that the oncogenic function of Bmi1 depends on regulation of p16(INK4A)/Rb rather than on regulation of p19(ARF)/p53. Human pituitary adenomas show Bmi1 overexpression in over 50% of the cases, which indicates that Bmi1 could be causally involved in formation of these tumors similarly as in our mouse model.

  4. EphA2-derived peptide vaccine with amphiphilic poly(gamma-glutamic acid) nanoparticles elicits an anti-tumor effect against mouse liver tumor.

    PubMed

    Yamaguchi, Shinjiro; Tatsumi, Tomohide; Takehara, Tetsuo; Sasakawa, Akira; Yamamoto, Masashi; Kohga, Keisuke; Miyagi, Takuya; Kanto, Tatsuya; Hiramastu, Naoki; Akagi, Takami; Akashi, Mitsuru; Hayashi, Norio

    2010-05-01

    The prognosis of liver cancer remains poor, but recent advances in nanotechnology offer promising possibilities for cancer treatment. Novel adjuvant, amphiphilic nanoparticles (NPs) composed of L: -phenylalanine (Phe)-conjugated poly(gamma-glutamic acid) (gamma-PGA-Phe NPs) having excellent capacity for carrying peptides, were found to have the potential for use as a peptide vaccine against tumor models overexpressing artificial antigens, such as ovalbumin (OVA). However, the anti-tumor potential of gamma-PGA-Phe NPs vaccines using much less immunogenic tumor-associated antigen (TAA)-derived peptide needs to be clarified. In this study, we evaluated the effectiveness of immunization with EphA2, recently identified TAA, derived peptide-immobilized gamma-PGA-Phe NPs (Eph-NPs) against mouse liver tumor of MC38 cells (EphA2-positive colon cancer cells). Immunization of normal mice with Eph-NPs resulted in generation of EphA2-specific type-1 CD8+ T cells. Immunization with Eph-NPs tended to provide a degree of anti-MC38 liver tumor protection more than that observed for immunization with the mixture of EphA2-derived peptide and complete Freund's adjuvant (Eph + CFA). Neither Eph-NPs nor Eph + CFA vaccines inhibited tumor growth of BL6, EphA2-negative melanoma cells. Splenocytes isolated from MC38-bearing mice treated with Eph-NPs showed strong and specific cytotoxic activity against MC38 cells. Immunization with Eph + CFA induced liver damage as evidenced by elevation of serum alanine aminotransferase, while Eph-NPs vaccination did not exhibit any toxic damage to the liver. These results demonstrated that immunization with Eph-NPs displayed anti-tumor effects against liver tumor by generating acquired immunity equivalent to the toxic adjuvant CFA, suggesting that safe gamma-PGA-Phe NPs could be applied clinically for the vaccine treatment of liver cancer.

  5. 2,3,7, 8-TETRACHLORODIBENZO-P-DIOXIN (TCDD)-MEDIATED OXIDATIVE STRESS IN FEMALE CYP1A-2 KNOCKOUT (CYP1A2-/-) MICE

    EPA Science Inventory

    2,3,7,8-Tetrachlordibenzo-p-dioxin (TCDD)-Mediated Oxidative Stress in Female CYP1A2 Knockout (CYP1A2-/-) Mice

    Deborah Burgin1, Janet Diliberto2, Linda Birnbaum2
    1UNC Toxicology; 2USEPA/ORD/NHEERL, RTP, NC

    Most of the effects due to TCDD exposure are mediated via...

  6. Endothelial Rab7 GTPase mediates tumor growth and metastasis in lysosomal acid lipase-deficient mice.

    PubMed

    Zhao, Ting; Ding, Xinchun; Yan, Cong; Du, Hong

    2017-11-24

    Tumors depend on their microenvironment for sustained growth, invasion, and metastasis. In this environment, endothelial cells (ECs) are an important stromal cell type interacting with malignant cells to facilitate tumor angiogenesis and cancer cell extravasation. Of note, lysosomal acid lipase (LAL) deficiency facilitates melanoma growth and metastasis. ECs from LAL-deficient ( lal -/- ) mice possess enhanced proliferation, migration, and permeability of inflammatory cells by activating the mammalian target of rapamycin (mTOR) pathway. Here we report that lal -/- ECs facilitated in vivo tumor angiogenesis, growth, and metastasis, largely by stimulating tumor cell proliferation, migration, adhesion, and transendothelial migration via increased expression of IL-6 and monocyte chemoattractant protein 1 (MCP-1). This prompted us to look for lysosomal proteins that are involved in lal -/- EC dysfunctions. We found that lal -/- ECs displayed increased expression of Rab7, a late endosome/lysosome-associated small GTPase. Moreover, Rab7 and mTOR were co-increased and co-localized to lysosomes and physically interacted in lal -/- ECs. Rab7 inhibition reversed lal -/- EC dysfunctions, including decreasing their enhanced migration and permeability of tumor-stimulatory myeloid cells, and suppressed EC-mediated stimulation of in vitro tumor cell transmigration, proliferation, and migration and in vivo tumor growth and metastasis. Finally, Rab7 inhibition reduced overproduction of reactive oxygen species and increased IL-6 and MCP-1 secretion in lal -/- ECs. Our results indicate that metabolic reprogramming resulting from LAL deficiency enhances the ability of ECs to stimulate tumor cell proliferation and metastasis through stimulation of lysosome-anchored Rab7 activity. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  7. Herpes vector-mediated delivery of marker genes to disseminated central nervous system tumors.

    PubMed

    Kramm, C M; Rainov, N G; Sena-Esteves, M; Chase, M; Pechan, P A; Chiocca, E A; Breakefield, X O

    1996-02-10

    The present study investigated the ability of a recombinant herpes simplex virus type 1 (HSV) vector to deliver genes into disseminated brain tumor foci through intrathecal injection of the vector. The animal model was designed to simulate brain tumors with cerebrospinal fluid (CSF) metastases, which are found especially in the pediatric population. 9L gliosarcoma cells were injected both into the right frontal lobe and in through the cisterna magna of adult rats. The HSV vector, hrR3, was inoculated intrathecally 5 days later. This vector is defective in the gene for ribonucleotide reductase, and, therefore, replicates preferentially in dividing cells; it retains an intact HSV-thymidine kinase gene (HSV-tk). Two days after injection of the vector, immunohistochemical staining for HSV thymidine kinase (HSV-TK) revealed expression in frontal tumors, as well as in leptomeningeal tumor foci along the entire neuroaxis. HSV-TK-immunopositive cells were most frequent in small tumors contacting the CSF pathways. Frontal lobe tumors showed the highest density of HSV-TK-immunopositive cells around their periphery with little expression in central parts. Some paraventricular neurons temporarily showed HSV-TK-immunolabeling at this early time point. The number of HSV-TK-immunopositive tumor cells markedly decreased 5 days after injection of the HSV vector. In all animals, some toxicity was observed in the first 2-4 days after virus injection with extensive leptomeningeal inflammation. In conclusion, intrathecal application of HSV vectors can mediate widespread transfer of the therapeutic HSV-tk gene into disseminated tumors throughout the brain and CSF pathways. Although there was marked toxicity associated with intrathecal injection of this vector, this mode of gene delivery offers a promising approach for treatment of CSF-metastases in conjunction with development of less toxic vectors.

  8. Modality of tumor endothelial VEGFR2 silencing-mediated improvement in intratumoral distribution of lipid nanoparticles.

    PubMed

    Yamamoto, Shoshiro; Kato, Akari; Sakurai, Yu; Hada, Tomoya; Harashima, Hideyoshi

    2017-04-10

    The vascular endothelial growth factor (VEGF)-mediated enhancement in vascular permeability is considered to be a major factor in tumor-targeting delivery via the enhanced permeability and retention (EPR) effect. We previously reported that the silencing of the endothelial VEGF receptor (VEGFR2) by a liposomal siRNA system (RGD-MEND) resulted in an enhanced intratumoral distribution of polyethylene glycol (PEG)-modified liposomes (LPs) in a renal cell carcinoma, a type of hypervascularized cancer, although the inhibition of VEGF signaling would be expected to decrease the permeability of the tumor vasculature. We herein report that the enhancement in the intratumoral distribution of LPs by VEGFR2 inhibition was dependent on the vascular type of the tumor (stroma vessel type; SV and tumor vessel type; TV). In the case of TV-type tumors (renal cell carcinoma and hepatocellular carcinoma), inhibiting VEGFR2 improved intratumoral distribution, while no effect was found in the case of SV-type tumors (colorectal cancer). Moreover, through a comparison of the intratumoral distribution of LPs with a variety of physical properties (100nm vs 400nm, neutral vs negative vs positive), VEGFR2 inhibition was found to alter the tumor microenvironment, including heparan sulfate proteoglycans (HSPGs). In addition, the results regarding the effect of the size of nanoparticles indicated that VEGFR2 inhibition improved the penetration of nanoparticles through the vessel wall, but not via permeability, suggesting the involvement of an unknown mechanism. Our findings suggest that a combination of anti-angiogenic therapy and delivery via the EPR effect would be useful in certain cases, and that altering the tumor microenvironment by VEGFR2 blockade has a drastic effect on the intratumoral distribution of nanoparticles. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. LAMP2A overexpression in breast tumors promotes cancer cell survival via chaperone-mediated autophagy.

    PubMed

    Saha, Tapas

    2012-11-01

    Lysosome-associated membrane protein type 2A (LAMP2A) is a key protein in the chaperone-mediated autophagy (CMA) pathway. LAMP2A helps in lysosomal uptake of modified and oxidatively damaged proteins directly into the lumen of lysosomes for degradation and protein turnover. Elevated expression of LAMP2A was observed in breast tumor tissues of all patients under investigation, suggesting a survival mechanism via CMA and LAMP2A. Reduced expression of the CMA substrates, GAPDH and PKM, was observed in most of the breast tumor tissues when compared with the normal adjacent tissues. Reactive oxygen species (ROS) mediated oxidative stress damages regulatory cellular components such as DNA, proteins and/or lipids. Protein carbonyl content (PCC) is widely used as a measure of total protein oxidation in cells. Ectopic expression of LAMP2A reduces PCC and thereby promotes cell survival during oxidative stress. Furthermore, inhibition of LAMP2A stimulates accumulation of GAPDH, AKT1 phosphorylation, generation of ROS, and induction of cellular apoptosis in breast cancer cells. Doxorubicin, which is a chemotherapeutic drug, often becomes ineffective against tumor cells with time due to chemotherapeutic resistance. Breast cancer cells deficient of LAMP2A demonstrate increased sensitivity to the drug. Thus, inhibiting CMA activity in breast tumor cells can be exploited as a potential therapeutic application in the treatment of breast cancer.

  10. Penfluridol suppresses glioblastoma tumor growth by Akt-mediated inhibition of GLI1

    PubMed Central

    Ranjan, Alok; Srivastava, Sanjay K.

    2017-01-01

    Glioblastoma (GBM) is the most common brain tumor with poor survival rate. Our results show that penfluridol, an antipsychotic drug significantly reduced the survival of ten adult and pediatric glioblastoma cell lines with IC50 ranging 2–5 μM after 72 hours of treatment and induced apoptosis. Penfluridol treatment suppressed the phosphorylation of Akt at Ser473 and reduced the expression of GLI1, OCT4, Nanog and Sox2 in several glioblastoma cell lines in a concentration-dependent manner. Inhibiting Akt with LY294002 and siRNA, or inhibiting GLI1 using GANT61, cyclopamine, siRNA and CRISPR/Cas9 resulted in enhanced cell growth suppressive effects of penfluridol. On the other hand, overexpression of GLI1 significantly attenuated the effects of penfluridol. Our results further demonstrated that penfluridol treatment inhibited the growth of U87MG tumors by 65% and 72% in subcutaneous and intracranial in vivo glioblastoma tumor models respectively. Immunohistochemical and western blot analysis of tumors revealed reduced pAkt (Ser 473), GLI1, OCT4 and increase in caspase-3 cleavage and TUNEL staining, confirming in vitro findings. Taken together, our results indicate that overall glioblastoma tumor growth suppression by penfluridol was associated with Akt-mediated inhibition of GLI1. PMID:28380428

  11. Penfluridol suppresses glioblastoma tumor growth by Akt-mediated inhibition of GLI1.

    PubMed

    Ranjan, Alok; Srivastava, Sanjay K

    2017-05-16

    Glioblastoma (GBM) is the most common brain tumor with poor survival rate. Our results show that penfluridol, an antipsychotic drug significantly reduced the survival of ten adult and pediatric glioblastoma cell lines with IC50 ranging 2-5 μM after 72 hours of treatment and induced apoptosis. Penfluridol treatment suppressed the phosphorylation of Akt at Ser473 and reduced the expression of GLI1, OCT4, Nanog and Sox2 in several glioblastoma cell lines in a concentration-dependent manner. Inhibiting Akt with LY294002 and siRNA, or inhibiting GLI1 using GANT61, cyclopamine, siRNA and CRISPR/Cas9 resulted in enhanced cell growth suppressive effects of penfluridol. On the other hand, overexpression of GLI1 significantly attenuated the effects of penfluridol. Our results further demonstrated that penfluridol treatment inhibited the growth of U87MG tumors by 65% and 72% in subcutaneous and intracranial in vivo glioblastoma tumor models respectively. Immunohistochemical and western blot analysis of tumors revealed reduced pAkt (Ser 473), GLI1, OCT4 and increase in caspase-3 cleavage and TUNEL staining, confirming in vitro findings. Taken together, our results indicate that overall glioblastoma tumor growth suppression by penfluridol was associated with Akt-mediated inhibition of GLI1.

  12. Singlet oxygen explicit dosimetry to predict local tumor control for HPPH-mediated photodynamic therapy

    NASA Astrophysics Data System (ADS)

    Penjweini, Rozhin; Kim, Michele M.; Ong, Yi Hong; Zhu, Timothy C.

    2017-02-01

    This preclinical study examines four dosimetric quantities (light fluence, photosensitizer photobleaching ratio, PDT dose, and reacted singlet oxygen ([1O2]rx)) to predict local control rate (LCR) for 2-(1-Hexyloxyethyl)-2-devinyl pyropheophorbide (HPPH)-mediated photodynamic therapy (PDT). Mice bearing radiation-induced fibrosarcoma (RIF) tumors were treated with different in-air fluences (135, 250 and 350 J/cm2) and in-air fluence rates (50, 75 and 150 mW/cm2) at 0.25 mg/kg HPPH and a drug-light interval of 24 hours using a 1 cm diameter collimated laser beam at 665 nm wavelength. A macroscopic model was used to calculate ([1O2]rx)) based on in vivo explicit dosimetry of the initial tissue oxygenation, photosensitizer concentration, and tissue optical properties. PDT dose was defined as a temporal integral of drug concentration and fluence rate (φ) at a 3 mm tumor depth. Light fluence rate was calculated throughout the treatment volume based on Monte-Carlo simulation and measured tissue optical properties. The tumor volume of each mouse was tracked for 30 days after PDT and Kaplan-Meier analyses for LCR were performed based on a tumor volume <=100 mm3, for four dose metrics: fluence, HPPH photobleaching rate, PDT dose, and ([1O2]rx)). The results of this study showed that ([1O2]rx)) is the best dosimetric quantity that can predict tumor response and correlate with LCR.

  13. Role of MicroRNA-26b in Glioma Development and Its Mediated Regulation on EphA2

    PubMed Central

    Wu, Ning; Zhao, Xiangzhong; Liu, Ming; Liu, Haizhou; Yao, Weicheng; Zhang, Yuyan; Cao, Shousong; Lin, Xiukun

    2011-01-01

    Background MicroRNAs (miRNAs) are short, non-coding RNAs that regulate the expression of multiple target genes. Deregulation of miRNAs is common in human tumorigenesis. Low level expression of miR-26b has been found in glioma cells. However, its underlying mechanism of action has not been determined. Methodology/Principal Findings Real-time PCR was employed to measure the expression level of miR-26b in glioma patients and cells. The level of miR-26b was inversely correlated with the grade of glioma. Ectopic expression of miR-26b inhibited the proliferation, migration and invasion of human glioma cells. A binding site for miR-26b was identified in the 3′UTR of EphA2. Over-expression of miR-26b in glioma cells repressed the endogenous level of EphA2 protein. Vasculogenic mimicry (VM) experiments were performed to further confirm the effects of miR-26b on the regulation of EphA2, and the results showed that miR-26b inhibited the VM processes which regulated by EphA2. Significance This study demonstrated that miR-26b may act as a tumor suppressor in glioma and it directly regulates EphA2 expression. EphA2 is a direct target of miR-26b, and the down-regulation of EphA2 mediated by miR-26b is dependent on the binding of miR-26b to a specific response element of microRNA in the 3′UTR region of EphA2 mRNA. PMID:21264258

  14. Low-intensity focused ultrasound mediated localized drug delivery for liver tumors in rabbits.

    PubMed

    Gong, Yuping; Wang, Zhigang; Dong, Guifang; Sun, Yang; Wang, Xi; Rong, Yue; Li, Maoping; Wang, Dong; Ran, Haitao

    2016-09-01

    To explore the antitumor effects of low-intensity focused ultrasound (LIFU) mediated localized drug delivery of adriamycin-microbubble-PLGA nanoparticle complexes on rabbits VX2 liver tumor. ADM-NMCs were prepared by covalent linking of ADM-PLGA nanoparticles (ADM-NPs) to the shell of the microbubbles. A fixed water bag filled with microbubbles was subjected to LIFU and non-focused ultrasound respectively, and the ultrasound images of which were recorded before and after ultrasonication. A total of 54 VX2 liver tumor-burdened rabbits were divided into six groups randomly, including control, ADM-NPs combined with LIFU, microbubbles combined with LIFU, ADM-NPs and microbubbles combined with LIFU, ADM-NMCs combined with LIFU and ADM-NMCs combined with Non-FUS. The tumor volume and volume inhibition rate (VIR) of tumor progression were calculated and compared. Apoptotic cells were labeled by terminal deoxyuridine nick end. Proliferating cell nuclear antigen was detected by immunohistochemistry. The median survival time of the animals were recorded and compared. ADM-NMCs were successfully prepared with an average diameter of 1721 nm. The highest VIR and apoptotic index (AI) were found in the group of ADM-NMCs combined with LIFU while the lowest proliferating index (PI) was simultaneously observed in this group. The median survival time of the rabbits in the ADM-NMCs combined with LIFU group was the longest (71days) among all groups. ADM-NMCs combined with LIFU could inhibit the rabbits VX2 liver tumor progress by delaying the tumor proliferation and accelerating apoptosis, which presents a novel process for liver tumor targeting chemotherapy.

  15. Adoptive transfer of human papillomavirus E7-specific CTL enhances tumor chemoresponse through the perforin/granzyme-mediated pathway.

    PubMed

    Sin, Jeong-Im; Kim, Jung-Min; Bae, Sung Hwa; Lee, In Hee; Park, Jong Sup; Ryoo, Hun Mo

    2009-05-01

    Adoptive cytotoxic T lymphocyte (CTL) therapy has an important implication in treating cancer patients. Here, we investigate whether adoptive transfer of human papillomavirus (HPV) E7-specific CTL can enhance tumor chemoresponse using an established cervical cancer animal model. Cisplatin-based chemotherapy plus CTL therapy showed an improved therapeutic effectiveness, along with antitumor protective responses to a parental tumor cell rechallenge. Cisplatin treatment dose-dependently increased the expression of Fas, intercellular adhesion molecule (ICAM)-1, and major histocompatibility complex (MHC) class I antigens (Ags) on tumor cells in vitro. However, CTL-expressing FasL failed to improve antitumor activity in vitro and in animals, resulting from nonfunctional Fas expressed on tumor cells. In contrast, ethylene glycol tetraacetic acid (EGTA) treatment blocked increased sensitivity of cisplatin-treated tumor cells to CTL-mediated killing in vitro, suggesting an important role of the perforin/granzyme-mediated pathway for improved therapeutic effectiveness. This notion was further confirmed by perforin knockout animal studies. Thus, this study shows that (i) modulation of Ag (Fas, ICAM-1) expression by tumor cells has little effect on their increased sensitivity to CTL-mediated killing, (ii) improved therapeutic effectiveness is mediated mainly through the perforin/granzyme-mediated tumor killing pathway, and (iii) a combination of chemotherapy and adoptive E7-specific CTL transfer augments antitumor therapeutic activity in vivo. This finding may have important implications for treating HPV-associated cervical cancer.

  16. IL-17 promotes tumor angiogenesis through Stat3 pathway mediated upregulation of VEGF in gastric cancer.

    PubMed

    Wu, Xiaoqin; Yang, Tao; Liu, Xiang; Guo, Jia Nian; Xie, Tingting; Ding, Yuanwei; Lin, Manpeng; Yang, Hui

    2016-04-01

    Gastric cancer is the world's second most common malignancy and is a major threat to global health. IL-17, a CD4 T cell-derived mediator of angiogenesis, plays a major role in stimulating angiogenesis by regulating the production of a variety of proangiogenic factors, including the vascular endothelial growth factor (VEGF). The level of VEGF expression correlates with tumor progression and metastasis in gastric cancer tissues. Abnormal activation of signal transducer and activator of transcription 3 (Stat3) rendered the tumor cells highly angiogenic, which is manifested by an increased microvascular density (MVD) and considered it as a potential molecular marker for poor prognosis in gastric cancer angiogenesis. We determined that IL-17A-induced VEGF upregulation and neovascularization through a Stat3-mediated signaling pathway and hypothesized that blocking the Stat3 activation by using JSI-124, an inhibitor of phosphorylated Stat3, could significantly reduce the VEGF expression and can thus prevent angiogenesis. We showed an inhibition of angiogenesis and tumor progression when JSI-124 was treated with IL-17A in the cells and xenografts in an animal model and suggested that targeting the Stat pathway with JSI-124 could derive an effective therapeutic target for gastric cancers and could be a promising drug in gastric cancer treatment.

  17. Tumor suppressor BTG1 promotes PRMT1-mediated ATF4 function in response to cellular stress.

    PubMed

    Yuniati, Laurensia; van der Meer, Laurens T; Tijchon, Esther; van Ingen Schenau, Dorette; van Emst, Liesbeth; Levers, Marloes; Palit, Sander A L; Rodenbach, Caroline; Poelmans, Geert; Hoogerbrugge, Peter M; Shan, Jixiu; Kilberg, Michael S; Scheijen, Blanca; van Leeuwen, Frank N

    2016-01-19

    Cancer cells are frequently exposed to physiological stress conditions such as hypoxia and nutrient limitation. Escape from stress-induced apoptosis is one of the mechanisms used by malignant cells to survive unfavorable conditions. B-cell Translocation Gene 1 (BTG1) is a tumor suppressor that is frequently deleted in acute lymphoblastic leukemia and recurrently mutated in diffuse large B cell lymphoma. Moreover, low BTG1 expression levels have been linked to poor outcome in several solid tumors. How loss of BTG1 function contributes to tumor progression is not well understood. Here, using Btg1 knockout mice, we demonstrate that loss of Btg1 provides a survival advantage to primary mouse embryonic fibroblasts (MEFs) under stress conditions. This pro-survival effect involves regulation of Activating Transcription Factor 4 (ATF4), a key mediator of cellular stress responses. We show that BTG1 interacts with ATF4 and positively modulates its activity by recruiting the protein arginine methyl transferase PRMT1 to methylate ATF4 on arginine residue 239. We further extend these findings to B-cell progenitors, by showing that loss of Btg1 expression enhances stress adaptation of mouse bone marrow-derived B cell progenitors. In conclusion, we have identified the BTG1/PRMT1 complex as a new modifier of ATF4 mediated stress responses.

  18. Tumor suppressor BTG1 promotes PRMT1-mediated ATF4 function in response to cellular stress

    PubMed Central

    Tijchon, Esther; van Ingen Schenau, Dorette; van Emst, Liesbeth; Levers, Marloes; Palit, Sander A.L.; Rodenbach, Caroline; Poelmans, Geert; Hoogerbrugge, Peter M.; Shan, Jixiu; Kilberg, Michael S.; Scheijen, Blanca; van Leeuwen, Frank N.

    2016-01-01

    Cancer cells are frequently exposed to physiological stress conditions such as hypoxia and nutrient limitation. Escape from stress-induced apoptosis is one of the mechanisms used by malignant cells to survive unfavorable conditions. B-cell Translocation Gene 1 (BTG1) is a tumor suppressor that is frequently deleted in acute lymphoblastic leukemia and recurrently mutated in diffuse large B cell lymphoma. Moreover, low BTG1 expression levels have been linked to poor outcome in several solid tumors. How loss of BTG1 function contributes to tumor progression is not well understood. Here, using Btg1 knockout mice, we demonstrate that loss of Btg1 provides a survival advantage to primary mouse embryonic fibroblasts (MEFs) under stress conditions. This pro-survival effect involves regulation of Activating Transcription Factor 4 (ATF4), a key mediator of cellular stress responses. We show that BTG1 interacts with ATF4 and positively modulates its activity by recruiting the protein arginine methyl transferase PRMT1 to methylate ATF4 on arginine residue 239. We further extend these findings to B-cell progenitors, by showing that loss of Btg1 expression enhances stress adaptation of mouse bone marrow-derived B cell progenitors. In conclusion, we have identified the BTG1/PRMT1 complex as a new modifier of ATF4 mediated stress responses. PMID:26657730

  19. Activated cytotoxic lymphocytes promote tumor progression by increasing the ability of 3LL tumor cells to mediate MDSC chemoattraction via Fas signaling

    PubMed Central

    Yang, Fei; Wei, Yinxiang; Cai, Zhijian; Yu, Lei; Jiang, Lingling; Zhang, Chengyan; Yan, Huanmiao; Wang, Qingqing; Cao, Xuetao; Liang, Tingbo; Wang, Jianli

    2015-01-01

    The Fas/FasL system transmits intracellular apoptotic signaling, inducing cell apoptosis. However, Fas signaling also exerts non-apoptotic functions in addition to inducing tumor cell apoptosis. For example, Fas signaling induces lung cancer tumor cells to produce prostaglandin E2 (PGE2) and recruit myeloid-derived suppressor cells (MDSCs). Activated cytotoxic T lymphocytes (CTLs) induce and express high levels of FasL, but the effects of Fas activation initiated by FasL in CTLs on apoptosis-resistant tumor cells remain largely unclear. We purified activated CD8+ T cells from OT-1 mice, evaluated the regulatory effects of Fas activation on tumor cell escape and investigated the relevant mechanisms. We found that CTLs induced tumor cells to secrete PGE2 and increase tumor cell-mediated chemoattraction of MDSCs via Fas signaling, which was favorable to tumor growth. Our results indicate that CTLs may participate in the tumor immune evasion process. To the best of our knowledge, this is a novel mechanism by which CTLs play a role in tumor escape. Our findings implicate a strategy to enhance the antitumor immune response via reduction of negative immune responses to tumors promoted by CTLs through Fas signaling. PMID:24769795

  20. Neoalbaconol inhibits angiogenesis and tumor growth by suppressing EGFR-mediated VEGF production.

    PubMed

    Yu, Xinfang; Li, Wei; Deng, Qipan; You, Shuo; Liu, Haidan; Peng, Songling; Liu, Xiaolan; Lu, Jingchen; Luo, Xiangjian; Yang, Lifang; Tang, Min; Weng, Xinxian; Yi, Wei; Liu, Wenbin; Wu, Shengqi; Ding, Zhihui; Feng, Tao; Zhou, Jian; Fan, Jia; Bode, Ann M; Dong, Zigang; Liu, Jikai; Cao, Ya

    2017-05-01

    Neoalbaconol, derived from Albatrellus confluens, shows anti-cancer activities in the previously study, but its role in angiogenesis is unknown. Here, we determined whether neoalbaconol could attenuate angiogenesis and how does it occur. Data demonstrated that neoalbaconol could inhibit the proliferation of breast cancer cells and induce apoptosis. Also, neoalbaconol suppressed vascular endothelial growth factor (VEGF)-induced human umbilical vascular endothelial cells (HUVECs) proliferation, migration, invasion, and capillary-like tube formation in vitro and reduced tumor angiogenesis in vivo. VEGF receptor activation and the downstream signal transduction cascades activation were inhibited by neoalbaconol. Additionally, neoalbaconol blocked EGFR-mediated VEGF production. EGFR overexpression reversed the neoalbaconol-induced VEGF reduction, confirming the importance of the EGFR inhibition in anti-angiogenesis of neoalbaconol. Furthermore, neoalbaconol inhibited tumor growth and tumor angiogenesis in a breast cancer xenograft model in vivo. Taken together, these results indicate that neoalbaconol could inhibit tumor angiogenesis and growth through direct suppression effects on vascular endothelial cells and reduction of proangiogenic factors in cancer cells. © 2017 Wiley Periodicals, Inc.

  1. RNA-Seq analysis of interferon inducible p204-mediated network in anti-tumor immunity.

    PubMed

    Jian, Jinlong; Wei, Wei; Yin, Guowei; Hettinghouse, Aubryanna; Liu, Chuanju; Shi, Yongxiang

    2018-04-24

    p204, a murine member of the interferon-inducible p200 protein family, and its human analogue, IFI16, have been shown to function as tumor suppressors in vitro, but the molecular events involved, in particular in vivo, remain unclear. Herein we induced the Lewis Lung carcinoma (LLC) murine model of human lung cancer in p204 null mice (KO) and their control littermates (WT). We compared the transcriptome in spleen from WT and p204 KO mice using a high-throughput RNA-sequencing array. A total 30.02 Gb of clean data were obtained, and overall Q30% was greater than 90.54%. More than 75% of clean data from 12 transcriptome samples were mapped to exons. The results showed that only 11 genes exhibited altered expression in untreated p204 KO mice relative to untreated WT mice, while 393 altered genes were identified in tumor-bearing p204 KO mice when compared with tumor-bearing WT mice. Further differentially expressed gene cluster and gene ontology consortium classification revealed that numerous cytokines and their receptors, chemoattractant molecules, and adhesion molecules were significantly induced in p204 KO mice. This study provides novel insights to the p204 network in anti-tumor immune response and also presents a foundation for future work concerning p204-mediated gene expressions and pathways.

  2. A Genome-Wide Loss-of-Function Screen Identifies SLC26A2 as a Novel Mediator of TRAIL Resistance.

    PubMed

    Dimberg, Lina Y; Towers, Christina G; Behbakht, Kian; Hotz, Taylor J; Kim, Jihye; Fosmire, Susan; Porter, Christopher C; Tan, Aik-Choon; Thorburn, Andrew; Ford, Heide L

    2017-04-01

    TRAIL is a potent death-inducing ligand that mediates apoptosis through the extrinsic pathway and serves as an important endogenous tumor suppressor mechanism. Because tumor cells are often killed by TRAIL and normal cells are not, drugs that activate the TRAIL pathway have been thought to have potential clinical value. However, to date, most TRAIL-related clinical trials have largely failed due to the tumor cells having intrinsic or acquired resistance to TRAIL-induced apoptosis. Previous studies to identify resistance mechanisms have focused on targeted analysis of the canonical apoptosis pathway and other known regulators of TRAIL receptor signaling. To identify novel mechanisms of TRAIL resistance in an unbiased way, we performed a genome-wide shRNA screen for genes that regulate TRAIL sensitivity in sublines that had been selected for acquired TRAIL resistance. This screen identified previously unknown mediators of TRAIL resistance including angiotensin II receptor 2, Crk-like protein, T-Box Transcription Factor 2, and solute carrier family 26 member 2 (SLC26A2). SLC26A2 downregulates the TRAIL receptors, DR4 and DR5, and this downregulation is associated with resistance to TRAIL. Its expression is high in numerous tumor types compared with normal cells, and in breast cancer, SLC26A2 is associated with a significant decrease in relapse-free survival. Implication: Our results shed light on novel resistance mechanisms that could affect the efficacy of TRAIL agonist therapies and highlight the possibility of using these proteins as biomarkers to identify TRAIL-resistant tumors, or as potential therapeutic targets in combination with TRAIL. Mol Cancer Res; 15(4); 382-94. ©2017 AACR . ©2017 American Association for Cancer Research.

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

    PubMed

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

    2016-01-12

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

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

    PubMed

    van der Most, Robbert G; Currie, Andrew J; Cleaver, Amanda L; Salmons, Joanne; Nowak, Anna K; Mahendran, Sathish; Larma, Irma; Prosser, Amy; Robinson, Bruce W S; Smyth, Mark J; Scalzo, Anthony A; Degli-Esposti, Mariapia A; Lake, Richard A

    2009-09-10

    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. 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. 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.

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

    PubMed Central

    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

  6. Tumor antigen ROR1 targeted drug delivery mediated selective leukemic but not normal B cell cytotoxicity in chronic lymphocytic leukemia

    PubMed Central

    Mani, Rajeswaran; Mao, Yicheng; Frissora, Frank W.; Chiang, Chi-Ling; Wang, Jiang; Zhao, Yuan; Wu, Yun; Yu, Bo; Yan, Ribai; Mo, Xiaokui; Yu, Lianbo; Flynn, Joseph; Jones, Jeffrey; Andritsos, Leslie; Baskar, Sivasubramanian; Rader, Christoph; Phelps, Mitch A; Chen, Ching-Shih; Lee, Robert J.; Byrd, John C.; Lee, L. James; Muthusamy, Natarajan

    2014-01-01

    Selective cytotoxicity to cancer cells without compromising their normal counterparts pose a huge challenge for traditional drug design. Here we developed a tumor antigen targeted delivery of immunonanoparticle carrying a novel non-immunosuppressive FTY720 derivative OSU-2S with potent cytotoxicity against leukemic B cells. OSU-2S induces activation of protein phosphatase 2A, phosphorylation and nuclear translocation of SHP1S591 and deregulation of multiple cellular processes in chronic lymphocytic leukemia (CLL) resulting in potent cytotoxicity. To preclude OSU-2S mediated effects on these ubiquitous phosphatases in unintended cells and avoid potential adverse effects we developed a OSU-2S targeted delivery immunonanoparticles (2A2-OSU-2S-ILP), that mediated selective cytotoxicity of CLL but not normal B cells through targeting receptor tyrosine kinase ROR1 expressed in leukemic but not normal B cells. Developing a novel spontaneous CLL mouse model expressing human ROR1 (hROR1) in all leukemic B cells, we demonstrate the therapeutic benefit of enhanced survival with 2A2-OSU-2S-ILP in-vivo. The newly developed non-immunosuppressive OSU-2S, its delivery using human CLL directed immunonanoparticles and the novel transgenic mouse model of CLL that expresses hROR1 exclusively in leukemic B cell surface are highly innovative and can be applied to CLL and other ROR1+ malignancies including mantle cell lymphoma and acute lymphoblastic leukemia. PMID:24947019

  7. Does mammographic density mediate risk factor associations with breast cancer? An analysis by tumor characteristics.

    PubMed

    Rice, Megan S; Tamimi, Rulla M; Bertrand, Kimberly A; Scott, Christopher G; Jensen, Matthew R; Norman, Aaron D; Visscher, Daniel W; Chen, Yunn-Yi; Brandt, Kathleen R; Couch, Fergus J; Shepherd, John A; Fan, Bo; Wu, Fang-Fang; Ma, Lin; Collins, Laura C; Cummings, Steven R; Kerlikowske, Karla; Vachon, Celine M

    2018-03-03

    Though mammographic density (MD) has been proposed as an intermediate marker of breast cancer risk, few studies have examined whether the associations between breast cancer risk factors and risk are mediated by MD, particularly by tumor characteristics. Our study population included 3392 cases (1105 premenopausal) and 8882 (3192 premenopausal) controls from four case-control studies. For established risk factors, we estimated the percent of the total risk factor association with breast cancer that was mediated by percent MD (secondarily, by dense area and non-dense area) for invasive breast cancer as well as for subtypes defined by the estrogen receptor (ER+/ER-), progesterone receptor (PR+/PR-), and HER2 (HER2+/HER2-). Analyses were conducted separately in pre- and postmenopausal women. Positive associations between prior breast biopsy and risk of invasive breast cancer as well as all subtypes were partially mediated by percent MD in pre- and postmenopausal women (percent mediated = 11-27%, p ≤ 0.02). In postmenopausal women, nulliparity and hormone therapy use were positively associated with invasive, ER+ , PR+ , and HER2- breast cancer; percent MD partially mediated these associations (percent mediated ≥ 31%, p ≤ 0.02). Further, among postmenopausal women, percent MD partially mediated the positive association between later age at first birth and invasive as well as ER+ breast cancer (percent mediated = 16%, p ≤ 0.05). Percent MD partially mediated the associations between breast biopsy, nulliparity, age at first birth, and hormone therapy with risk of breast cancer, particularly among postmenopausal women, suggesting that these risk factors at least partially influence breast cancer risk through changes in breast tissue composition.

  8. The EphA2 Receptor and EphrinA1 Ligand in Solid Tumors: Function and Therapeutic Targeting

    PubMed Central

    Wykosky, Jill; Debinski, Waldemar

    2013-01-01

    The Eph receptor tyrosine kinases and ephrin ligands have been studied extensively for their roles in developmental processes. In recent years, Eph receptors and ephrins have been found to be integral players in cancer formation and progression. Among these are EphA2 and ephrinA1, which are involved in the development and maintenance of many different types of solid tumors. The function of EphA2 and ephrinA1 in tumorigenesis and tumor progression is complex and seems to be dependent on cell type and microenvironment. These variables affect the expression of the EphA2 and ephrinA1 proteins, the pathways through which they induce signaling, and the functional consequences of that signaling on the behavior of tumor cells and tumor-associated cells. This review will specifically focus on the roles that EphA2 and ephrinA1 play in the different cell types that contribute to the malignancy of solid tumors, with emphasis on the opportunities for therapeutic targeting. PMID:19074825

  9. The EphA2 receptor and ephrinA1 ligand in solid tumors: function and therapeutic targeting.

    PubMed

    Wykosky, Jill; Debinski, Waldemar

    2008-12-01

    The Eph receptor tyrosine kinases and ephrin ligands have been studied extensively for their roles in developmental processes. In recent years, Eph receptors and ephrins have been found to be integral players in cancer formation and progression. Among these are EphA2 and ephrinA1, which are involved in the development and maintenance of many different types of solid tumors. The function of EphA2 and ephrinA1 in tumorigenesis and tumor progression is complex and seems to be dependent on cell type and microenvironment. These variables affect the expression of the EphA2 and ephrinA1 proteins, the pathways through which they induce signaling, and the functional consequences of that signaling on the behavior of tumor cells and tumor-associated cells. This review will specifically focus on the roles that EphA2 and ephrinA1 play in the different cell types that contribute to the malignancy of solid tumors, with emphasis on the opportunities for therapeutic targeting.

  10. Identification of Sleeping Beauty transposon insertions in solid tumors using linker-mediated PCR.

    PubMed

    Janik, Callie L; Starr, Timothy K

    2013-02-01

    Genomic, proteomic, transcriptomic, and epigenomic analyses of human tumors indicate that there are thousands of anomalies within each cancer genome compared to matched normal tissue. Based on these analyses it is evident that there are many undiscovered genetic drivers of cancer(1). Unfortunately these drivers are hidden within a much larger number of passenger anomalies in the genome that do not directly contribute to tumor formation. Another aspect of the cancer genome is that there is considerable genetic heterogeneity within similar tumor types. Each tumor can harbor different mutations that provide a selective advantage for tumor formation(2). Performing an unbiased forward genetic screen in mice provides the tools to generate tumors and analyze their genetic composition, while reducing the background of passenger mutations. The Sleeping Beauty (SB) transposon system is one such method(3). The SB system utilizes mobile vectors (transposons) that can be inserted throughout the genome by the transposase enzyme. Mutations are limited to a specific cell type through the use of a conditional transposase allele that is activated by Cre Recombinase. Many mouse lines exist that express Cre Recombinase in specific tissues. By crossing one of these lines to the conditional transposase allele (e.g. Lox-stop-Lox-SB11), the SB system is activated only in cells that express Cre Recombinase. The Cre Recombinase will excise a stop cassette that blocks expression of the transposase allele, thereby activating transposon mutagenesis within the designated cell type. An SB screen is initiated by breeding three strains of transgenic mice so that the experimental mice carry a conditional transposase allele, a concatamer of transposons, and a tissue-specific Cre Recombinase allele. These mice are allowed to age until tumors form and they become moribund. The mice are then necropsied and genomic DNA is isolated from the tumors. Next, the genomic DNA is subjected to linker-mediated

  11. Targeting genomic rearrangements in tumor cells through Cas9-mediated insertion of a suicide gene.

    PubMed

    Chen, Zhang-Hui; Yu, Yan P; Zuo, Ze-Hua; Nelson, Joel B; Michalopoulos, George K; Monga, Satdatshan; Liu, Silvia; Tseng, George; Luo, Jian-Hua

    2017-06-01

    Specifically targeting genomic rearrangements and mutations in tumor cells remains an elusive goal in cancer therapy. Here, we used Cas9-based genome editing to introduce the gene encoding the prodrug-converting enzyme herpes simplex virus type 1 thymidine kinase (HSV1-tk) into the genomes of cancer cells carrying unique sequences resulting from genome rearrangements. Specifically, we targeted the breakpoints of TMEM135-CCDC67 and MAN2A1-FER fusions in human prostate cancer or hepatocellular carcinoma cells in vitro and in mouse xenografts. We designed one adenovirus to deliver the nickase Cas9 D10A and guide RNAs targeting the breakpoint sequences, and another to deliver an EGFP-HSV1-tk construct flanked by sequences homologous to those surrounding the breakpoint. Infection with both viruses resulted in breakpoint-dependent expression of EGFP-tk and ganciclovir-mediated apoptosis. When mouse xenografts were treated with adenoviruses and ganciclovir, all animals showed decreased tumor burden and no mortality during the study. Thus, Cas9-mediated suicide-gene insertion may be a viable genotype-specific cancer therapy.

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

    PubMed

    Chung, Stephanie Tsang Mui; Geerts, Dirk; Roseman, Kim; Renaud, Ashleigh; Connelly, Linda

    2017-02-01

    It is widely recognized that inflammation promotes breast cancer invasion and metastasis. Given the complex nature of the breast tumor inflammatory microenvironment, much remains to be understood of the molecular mechanisms that govern these effects. We have previously shown that osteoprotegerin knockdown in breast cancer cells resulted in reduced invasion and metastasis. Here we present novel insight into the role of osteoprotegerin in inflammation-driven tumor progression in breast cancer by investigating the link between osteoprotegerin, macrophages and the potent pro-inflammatory cytokine Interleukin-1beta. We used human breast cancer cell lines to investigate the effects of Interleukin-1beta treatment on osteoprotegerin secretion as measured by ELISA. We analyzed public datasets containing human breast cancer genome-wide mRNA expression data to reveal a significant and positive correlation between osteoprotegerin mRNA expression and the mRNA expression of Interleukin-1beta and of monocyte chemoattractant protein CC-chemokine ligand 2. Osteoprotegerin, Interleukin-1beta and CC-chemokine ligand 2 mRNA levels were also examined by qPCR on cDNA from normal and cancerous human breast tissue. We determined the effect of Interleukin-1beta-producing macrophages on osteoprotegerin expression by co-culturing breast cancer cells and differentiated THP-1 macrophages. Immunohistochemistry was performed on human breast tumor tissue microarrays to assess macrophage infiltration and osteoprotegerin expression. To demonstrate that osteoprotegerin mediated functional effects of Interleukin-1beta we performed cell invasion studies with control and OPG siRNA knockdown on Interleukin-1beta-treated breast cancer cells. We report that Interleukin-1beta induces osteoprotegerin secretion, independent of breast cancer subtype and basal osteoprotegerin levels. Co-culture of breast cancer cells with Interleukin-1beta-secreting macrophages resulted in a similar increase in osteoprotegerin

  13. Targeted Nanocurcumin Therapy Using Annexin A2 Anitbody Improves Tumor Accumulation and Therapeutic Efficacy Against Highly Metastatic Breast Cancer.

    PubMed

    Mukerjee, Anindita; Ranjan, Anmalendu P; Vishwanatha, Jamboor K

    2016-07-01

    A major challenge in pharmaceutical research is effective targeting strategies to their sites of action. Emerging knowledge and the current progress in nanotechnology based delivery systems has opened up exciting ways towards successful targeted nanodelivery systems. For cancer therapy, nanoparticle-based drug formulations hold several advantages over free drugs, including improved pharmacokinetics, enhanced tumor accumulation, reduced systemic exposure and side effects and better patient compliance. The goal of this study was to validate the in vivo targeting potential and evaluate the combinatorial therapeutic potential of novel Annexin A2 (AnxA2) antibody-conjugated curcumin loaded poly(lactic-co-glycolic acid) (PLGA) nanoparticles (AnxA2-CPNP) against metastatic breast cancer. As a first step, we demonstrated that the cell-surface expression of AnxA2 is increases during breast cancer progression with very high expression in highly malignant cancer cells and basal expression in non-malignant cells. This confirmed AnxA2 as an excellent target for targeting our curcumin nanoparticles. Our results indicate that AnxA2-CPNP showed increased uptake in highly metastatic breast cancer cells than untargeted nanoparticles due to the differential AnxA2 expression. Cell viability, plasmin generation and wound healing assays reveal that AnxA2-CPNPs effectively inhibited cell proliferation, invasion and migration, key elements for cancer growth and metastasis. Further, angiogenesis assay illustrated that AnxA2-CPNPs decreased the formation of tube capillaries, thus inhibiting neoangiogenesis, a critical element in tumor growth. Live animal imaging demonstrated that AnxA2-PNPs and AnxA2-CPNPs effectively targeted and accumulated in the tumor as seen by the increased fluorescence intensity on the live scans. Xenograft studies in mice showed significant regression of breast tumor as a result of both effective targeting, accumulation and sustained release of curcumin in the tumor

  14. IgE/FcεRI-mediated antigen cross-presentation by dendritic cells enhances anti-tumor immune responses

    PubMed Central

    Platzer, Barbara; Elpek, Kutlu G.; Cremasco, Viviana; Baker, Kristi; Stout, Madeleine M; Schultz, Cornelia; Dehlink, Eleonora; Shade, Kai-Ting C.; Anthony, Robert M.; Blumberg, Richard S.; Turley, Shannon J.; Fiebiger, Edda

    2015-01-01

    SUMMARY Epidemiologic studies discovered an inverse association between Immunoglobulin E (IgE)-mediated allergies and cancer, implying tumor-protective properties of IgE. The underlying immunologic mechanisms remain, however, poorly understood. Antigen cross-presentation by dendritic cells (DCs) is key for anti-tumor immunity because of 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, novel receptor-mediated pathway as 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. PMID:25753415

  15. Hapten-induced contact hypersensitivity, autoimmune reactions, and tumor regression: plausibility of mediating antitumor immunity.

    PubMed

    Erkes, Dan A; Selvan, Senthamil R

    2014-01-01

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

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

    PubMed Central

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

    2017-01-01

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

  17. Feasibility of Affibody Molecule-Based PNA-Mediated Radionuclide Pretargeting of Malignant Tumors

    PubMed Central

    Honarvar, Hadis; Westerlund, Kristina; Altai, Mohamed; Sandström, Mattias; Orlova, Anna; Tolmachev, Vladimir; Karlström, Amelie Eriksson

    2016-01-01

    Affibody molecules are small (7 kDa), non-immunoglobulin scaffold proteins with a potential as targeting agents for radionuclide imaging of cancer. However, high renal re-absorption of Affibody molecules prevents their use for radionuclide therapy with residualizing radiometals. We hypothesized that the use of Affibody-based peptide nucleic acid (PNA)-mediated pretargeting would enable higher accumulation of radiometals in tumors than in kidneys. To test this hypothesis, we designed an Affibody-PNA chimera ZHER2:342-SR-HP1 containing a 15-mer HP1 PNA recognition tag and a complementary HP2 hybridization probe permitting labeling with both 125I and 111In. 111In-ZHER2:342-SR-HP1 bound specifically to HER2-expressing BT474 and SKOV-3 cancer cells in vitro, with a KD of 6±2 pM for binding to SKOV-3 cells. Specific high affinity binding of the radiolabeled complementary PNA probe 111In-/125I-HP2 to ZHER2:342-SR-HP1 pre-treated cells was demonstrated. 111In-ZHER2:342-SR-HP1 demonstrated specific accumulation in SKOV-3 xenografts in BALB/C nu/nu mice and rapid clearance from blood. Pre-saturation of SKOV-3 with non-labeled anti-HER2 Affibody or the use of HER2-negative Ramos xenografts resulted in significantly lower tumor uptake of 111In-ZHER2:342-SR-HP1. The complementary PNA probe 111In/125I-HP2 accumulated in SKOV-3 xenografts when ZHER2:342-SR-HP1 was injected 4 h earlier. The tumor accumulation of 111In/125I-HP2 was negligible without ZHER2:342-SR-HP1 pre-injection. The uptake of 111In-HP2 in SKOV-3 xenografts was 19±2 %ID/g at 1 h after injection. The uptake in blood and kidneys was approximately 50- and 2-fold lower, respectively. In conclusion, we have shown that the use of Affibody-based PNA-mediated pretargeting enables specific delivery of radiometals to tumors and provides higher radiometal concentration in tumors than in kidneys. PMID:26722376

  18. Feasibility of Affibody Molecule-Based PNA-Mediated Radionuclide Pretargeting of Malignant Tumors.

    PubMed

    Honarvar, Hadis; Westerlund, Kristina; Altai, Mohamed; Sandström, Mattias; Orlova, Anna; Tolmachev, Vladimir; Karlström, Amelie Eriksson

    2016-01-01

    Affibody molecules are small (7 kDa), non-immunoglobulin scaffold proteins with a potential as targeting agents for radionuclide imaging of cancer. However, high renal re-absorption of Affibody molecules prevents their use for radionuclide therapy with residualizing radiometals. We hypothesized that the use of Affibody-based peptide nucleic acid (PNA)-mediated pretargeting would enable higher accumulation of radiometals in tumors than in kidneys. To test this hypothesis, we designed an Affibody-PNA chimera ZHER2:342-SR-HP1 containing a 15-mer HP1 PNA recognition tag and a complementary HP2 hybridization probe permitting labeling with both (125)I and (111)In. (111)In-ZHER2:342-SR-HP1 bound specifically to HER2-expressing BT474 and SKOV-3 cancer cells in vitro, with a KD of 6±2 pM for binding to SKOV-3 cells. Specific high affinity binding of the radiolabeled complementary PNA probe (111)In-/(125)I-HP2 to ZHER2:342-SR-HP1 pre-treated cells was demonstrated. (111)In-ZHER2:342-SR-HP1 demonstrated specific accumulation in SKOV-3 xenografts in BALB/C nu/nu mice and rapid clearance from blood. Pre-saturation of SKOV-3 with non-labeled anti-HER2 Affibody or the use of HER2-negative Ramos xenografts resulted in significantly lower tumor uptake of (111)In-ZHER2:342-SR-HP1. The complementary PNA probe (111)In/(125)I-HP2 accumulated in SKOV-3 xenografts when ZHER2:342-SR-HP1 was injected 4 h earlier. The tumor accumulation of (111)In/(125)I-HP2 was negligible without ZHER2:342-SR-HP1 pre-injection. The uptake of (111)In-HP2 in SKOV-3 xenografts was 19±2 %ID/g at 1 h after injection. The uptake in blood and kidneys was approximately 50- and 2-fold lower, respectively. In conclusion, we have shown that the use of Affibody-based PNA-mediated pretargeting enables specific delivery of radiometals to tumors and provides higher radiometal concentration in tumors than in kidneys.

  19. E2f8 mediates tumor suppression in postnatal liver development

    PubMed Central

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

    2016-01-01

    E2F-mediated transcriptional repression of cell cycle–dependent gene expression is critical for the control of cellular proliferation, survival, and development. E2F signaling also interacts with transcriptional programs that are downstream of genetic predictors for cancer development, including hepatocellular carcinoma (HCC). Here, we evaluated the function of the atypical repressor genes E2f7 and E2f8 in adult liver physiology. Using several loss-of-function alleles in mice, we determined that combined deletion of E2f7 and E2f8 in hepatocytes leads to HCC. Temporal-specific ablation strategies revealed that E2f8’s tumor suppressor role is critical during the first 2 weeks of life, which correspond to a highly proliferative stage of postnatal liver development. Disruption of E2F8’s DNA binding activity phenocopied the effects of an E2f8 null allele and led to HCC. Finally, a profile of chromatin occupancy and gene expression in young and tumor-bearing mice identified a set of shared targets for E2F7 and E2F8 whose increased expression during early postnatal liver development is associated with HCC progression in mice. Increased expression of E2F8-specific target genes was also observed in human liver biopsies from HCC patients compared to healthy patients. In summary, these studies suggest that E2F8-mediated transcriptional repression is a critical tumor suppressor mechanism during postnatal liver development. PMID:27454291

  20. 14-3-3 mediated regulation of the tumor suppressor protein, RASSF1A.

    PubMed

    Ghazaleh, Haya Abu; Chow, Renfred S; Choo, Sheryl L; Pham, Diana; Olesen, Jamie D; Wong, Russell X; Onyskiw, Christina; Baksh, Shairaz

    2010-02-01

    Death receptor-dependent apoptosis is an important mechanism of growth control. It has been demonstrated that Ras association domain family protein 1A (RASSF1A) is a tumor suppressor protein involved in death receptor-dependent apoptosis. However, it is unclear how RASSF1A-mediated cell death is initiated. We have now detailed 14-3-3 dependent regulation of RASSF1A-mediated cell death. We demonstrate that basal association of RASSF1A with 14-3-3 was lost following stimulation with tumor necrosis factor alpha (TNFalpha) or TNFalpha related apoptosis inducing ligand (TRAIL). Subsequent to the loss of 14-3-3 association, RASSF1A associated with modulator of apoptosis (MOAP-1) followed by death receptor association with either TNFalpha receptor 1 (TNF-R1) or TRAIL receptor 1 (TRAIL-R1). 14-3-3 association required basal phosphorylation by the serine/threonine kinase, glycogen synthase kinase 3beta (GSK-3beta), on serine 175, 178, and 179. Mutation of these critical serines resulted in the loss of 14-3-3 association and earlier recruitment of RASSF1A to MOAP-1, TNF-R1, and TRAIL-R1. Furthermore, stable cells containing a triple serine mutant of RASSF1A [serine (S) 175 to alanine (A) [S175A], S178A, and S179A] resulted in increased basal cell death, enhanced Annexin V staining and enhanced cleavage of poly (ADP-ribose) polymerase (PARP) following TNFalpha stimulation when compared to stable cells containing wild type RASSF1A. RASSF1A-mediated cell death is, therefore, tightly controlled by 14-3-3 association.

  1. Critical tumor suppressor function mediated by epithelial Mig-6 in endometrial cancer

    PubMed Central

    Kim, Tae Hoon; Lee, Dong-Kee; Cho, Sung-Nam; Orvis, Grant D.; Behringer, Richard R.; Lydon, John P.; Ku, Bon Jeong; McCampbell, Adrienne S.; Broaddus, Russell R.; Jeong, Jae-Wook

    2013-01-01

    Endometrial cancer is preceded by endometrial hyperplasia, unopposed estrogen exposure and genetic alterations, but the precise causes of endometrial cancer remain uncertain. Mig-6, mainly known as a negative regulator of the EGF receptor, is an important mediator of progesterone signaling in the uterus, where it mediates tumor suppression by modulating endometrial stromal-epithelial communications. In this study, we investigated the function of Mig-6 in the uterine epithelium using a tissue-specific gene knockout strategy, in which floxed Mig-6 (Mig-6f/f) mice were crossed to Wnt7a-Cre mice (Wnt7acre+ Mig-6f/f). Wnt7acre+ Mig-6f/f mice developed endometrial hyperplasia and estrogen-dependent endometrial cancer, exhibiting increased proliferation in epithelial cells as well as apoptosis in sub-epithelial stromal cells. We documented increased expression of NOTCH1 and BIRC3 in epithelial cells of Wnt7acre+ Mig-6f/f mice and decreased expression of the progesterone receptor (PR) in stromal cells. Progesterone therapy controls endometrial growth and prevents endometrial cancer, but the effectiveness of progesterone as a treatment for women with endometrial cancer is less clear. We noted that the hyperplasic phenotype of Wnt7acre+ Mig-6f/f mice was prevented by progesterone treatment, whereas this treatment had no effect in PRcre/+ Mig-6f/f mice where Mig-6 was deleted in both the epithelial and stromal compartments of the uterus. In contrast, activation of progesterone signaling in the stroma regulated proliferation and apoptosis in the epithelium via suppression of ERα signaling there. In summary, our results establish that epithelial Mig-6 functions as a critical tumor suppressor that mediates the ability of progesterone to prevent the development of endometrial cancer. PMID:23811943

  2. Tumor

    MedlinePlus

    ... works Sometimes benign tumors may be removed for cosmetic reasons or to improve symptoms. Benign tumors of the brain may be removed because of their location or harmful effect on the surrounding normal brain tissue. If a ...

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

    NASA Astrophysics Data System (ADS)

    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

  4. Murine Dendritic Cells Pulsed with Whole Tumor Lysates Mediate Potent Antitumor Immune Responses in vitro and in vivo

    NASA Astrophysics Data System (ADS)

    Fields, R. C.; Shimizu, K.; Mule, J. J.

    1998-08-01

    The highly efficient nature of dendritic cells (DC) as antigen-presenting cells raises the possibility of uncovering in tumor-bearing hosts very low levels of T cell reactivity to poorly immunogenic tumors that are virtually undetectable by other means. Here, we demonstrate the in vitro and in vivo capacities of murine bone marrow-derived, cytokine-driven DC to elicit potent and specific anti-tumor responses when pulsed with whole tumor lysates. Stimulation of naive spleen-derived T cells by tumor lysate-pulsed DC generated tumor-specific proliferative cytokine release and cytolytic reactivities in vitro. In addition, in two separate strains of mice with histologically distinct tumors, s.c. injections of DC pulsed with whole tumor lysates effectively primed these animals to reject subsequent lethal challenges with viable parental tumor cells and, important to note, also mediated significant reductions in the number of metastases established in the lungs. Tumor rejection depended on host-derived CD8+ T cells and, to a lesser extent, CD4+ T cells. Spleens from mice that had rejected their tumors contained specific precursor cytotoxic T lymphocytes. The use of whole tumor lysates as a source of tumor-associated antigen(s) for pulsing of DC circumvents several limitations encountered with other methods as well as provides certain distinct advantages, which are discussed. These data serve as rationale for our recent initiation of a phase I clinical trial of immunization with autologous tumor lysate-pulsed DC in adult and pediatric cancer patients.

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

    PubMed Central

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

    1996-01-01

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

  6. EphA2 Receptor Signaling Mediates Inflammatory Responses in Lipopolysaccharide-Induced Lung Injury.

    PubMed

    Hong, Ji Young; Shin, Mi Hwa; Chung, Kyung Soo; Kim, Eun Young; Jung, Ji Ye; Kang, Young Ae; Kim, Young Sam; Kim, Se Kyu; Chang, Joon; Park, Moo Suk

    2015-07-01

    Eph receptors and ephrin ligands have several functions including angiogenesis, cell migration, axon guidance, fluid homeostasis, oncogenesis, inflammation and injury repair. The EphA2 receptor potentially mediates the regulation of vascular permeability and inflammation in response to lung injury. Mice were divided into 3 experimental groups to study the role of EphA2 signaling in the lipopolysaccharide (LPS)-induced lung injury model i.e., IgG+phosphate-buffered saline (PBS) group (IgG instillation before PBS exposure), IgG+LPS group (IgG instillation before LPS exposure) and EphA2 monoclonal antibody (mAb)+LPS group (EphA2 mAb pretreatment before LPS exposure). EphA2 and ephrinA1 were upregulated in LPS-induced lung injury. The lung injury score of the EphA2 mAb+LPS group was lower than that of the IgG+LPS group (4.30±2.93 vs. 11.45±1.20, respectively; p=0.004). Cell counts (EphA2 mAb+LPS: 11.33×10(4)±8.84×10(4) vs. IgG+LPS: 208.0×10(4)±122.6×10(4); p=0.018) and total protein concentrations (EphA2 mAb+LPS: 0.52±0.41 mg/mL vs. IgG+LPS: 1.38±1.08 mg/mL; p=0.192) were decreased in EphA2 mAb+LPS group, as compared to the IgG+LPS group. In addition, EphA2 antagonism reduced the expression of phospho-p85, phosphoinositide 3-kinase 110γ, phospho-Akt, nuclear factor κB, and proinflammatory cytokines. This results of the study indicated a role for EphA2-ephrinA1 signaling in the pathogenesis of LPS-induced lung injury. Furthermore, EphA2 antagonism inhibits the phosphoinositide 3-kinase-Akt pathway and attenuates inflammation.

  7. EphA2 Receptor Signaling Mediates Inflammatory Responses in Lipopolysaccharide-Induced Lung Injury

    PubMed Central

    Hong, Ji Young; Shin, Mi Hwa; Chung, Kyung Soo; Kim, Eun Young; Jung, Ji Ye; Kang, Young Ae; Kim, Young Sam; Kim, Se Kyu; Chang, Joon

    2015-01-01

    Background Eph receptors and ephrin ligands have several functions including angiogenesis, cell migration, axon guidance, fluid homeostasis, oncogenesis, inflammation and injury repair. The EphA2 receptor potentially mediates the regulation of vascular permeability and inflammation in response to lung injury. Methods Mice were divided into 3 experimental groups to study the role of EphA2 signaling in the lipopolysaccharide (LPS)-induced lung injury model i.e., IgG+phosphate-buffered saline (PBS) group (IgG instillation before PBS exposure), IgG+LPS group (IgG instillation before LPS exposure) and EphA2 monoclonal antibody (mAb)+LPS group (EphA2 mAb pretreatment before LPS exposure). Results EphA2 and ephrinA1 were upregulated in LPS-induced lung injury. The lung injury score of the EphA2 mAb+LPS group was lower than that of the IgG+LPS group (4.30±2.93 vs. 11.45±1.20, respectively; p=0.004). Cell counts (EphA2 mAb+LPS: 11.33×104±8.84×104 vs. IgG+LPS: 208.0×104±122.6×104; p=0.018) and total protein concentrations (EphA2 mAb+LPS: 0.52±0.41 mg/mL vs. IgG+LPS: 1.38±1.08 mg/mL; p=0.192) were decreased in EphA2 mAb+LPS group, as compared to the IgG+LPS group. In addition, EphA2 antagonism reduced the expression of phospho-p85, phosphoinositide 3-kinase 110γ, phospho-Akt, nuclear factor κB, and proinflammatory cytokines. Conclusion This results of the study indicated a role for EphA2-ephrinA1 signaling in the pathogenesis of LPS-induced lung injury. Furthermore, EphA2 antagonism inhibits the phosphoinositide 3-kinase-Akt pathway and attenuates inflammation. PMID:26175775

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

    PubMed

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

    2017-02-01

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

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

    PubMed

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

    2013-08-01

    Recently, heterozygous mutations in exon 2 of the mediator complex subunit 12 gene have been described in 50% to 70% of uterine leiomyomas; the recurrent nature of these mutations suggests an important role in their pathogenesis. Mediator complex subunit 12 is involved in regulation of transcription and Wnt signaling. So far, little is known about the pathogenesis of the different subtypes of extrauterine leiomyomas and leiomyosarcomas. We performed mutation analysis of mediator complex subunit 12 and immunohistochemistry for β-catenin, using 69 tumors of 64 patients including 19 uterine leiomyomas, 6 abdominal leiomyomas, 9 angioleiomyomas, 5 piloleiomyomas, and 7 uterine and 23 soft tissue leiomyosarcomas. In line with previous observations, 58% of uterine leiomyomas carried a mediator complex subunit 12 mutation. However, all other extrauterine leiomyomas were negative with the exception of 1 abdominal leiomyoma with a likely primary uterine origin. Of the 30 leiomyosarcomas, only 1 uterine tumor harbored a mutation. A new observation is the identification of 3 tumors with a homozygous mutation; a monosomy X or interstitial deletion was excluded. β-Catenin immunohistochemistry showed nuclear positivity in only 55% of the mediator complex subunit 12-mutated uterine leiomyomas, suggesting the involvement of pathways other than canonical Wnt signaling in tumorigenesis. Interestingly, 80% of mediator complex subunit 12 wild-type sporadic piloleiomyomas displayed nuclear β-catenin positivity, indicating its involvement in this leiomyoma subtype. The lack of mediator complex subunit 12 mutations in extrauterine leiomyomas and leiomyosarcomas indicates that these tumors arise through a different pathway, emphasizing the genetic heterogeneity of smooth muscle tumors. Copyright © 2013 Elsevier Inc. All rights reserved.

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

    PubMed Central

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

    2017-01-01

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

  11. EPAS-1 Mediates SP-1-Dependent FBI-1 Expression and Regulates Tumor Cell Survival and Proliferation

    PubMed Central

    Wang, Xiaogang; Cao, Peng; Li, Zhiqing; Wu, Dongyang; Wang, Xi; Liang, Guobiao

    2014-01-01

    Factor binding IST-1 (FBI-1) plays an important role in oncogenic transformation and tumorigenesis. As FBI-1 is over-expressed in multiple human cancers, the regulation of itself would provide new effective options for cancer intervention. In this work, we aimed to study the role that EPAS-1 plays in regulating FBI-1. We use the fact that specificity protein-1 (SP-1) is one of the crucial transcription factors of FBI-1, and that SP-1 can interact with the endothelial pas domain protein-1 (EPAS-1) for the induction of hypoxia related genes. The study showed that EPAS-1 plays an indispensible role in SP-1 transcription factor-mediated FBI-1 induction, and participated in tumor cell survival and proliferation. Thus, EPAS-1 could be a novel target for cancer therapeutics. PMID:25192290

  12. EPAS-1 mediates SP-1-dependent FBI-1 expression and regulates tumor cell survival and proliferation.

    PubMed

    Wang, Xiaogang; Cao, Peng; Li, Zhiqing; Wu, Dongyang; Wang, Xi; Liang, Guobiao

    2014-09-04

    Factor binding IST-1 (FBI-1) plays an important role in oncogenic transformation and tumorigenesis. As FBI-1 is over-expressed in multiple human cancers, the regulation of itself would provide new effective options for cancer intervention. In this work, we aimed to study the role that EPAS-1 plays in regulating FBI-1. We use the fact that specificity protein-1 (SP-1) is one of the crucial transcription factors of FBI-1, and that SP-1 can interact with the endothelial pas domain protein-1 (EPAS-1) for the induction of hypoxia related genes. The study showed that EPAS-1 plays an indispensible role in SP-1 transcription factor-mediated FBI-1 induction, and participated in tumor cell survival and proliferation. Thus, EPAS-1 could be a novel target for cancer therapeutics.

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

    PubMed

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

    2017-07-28

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

  14. Hypoxia-Mediated Epigenetic Regulation of Stemness in Brain Tumor Cells.

    PubMed

    Prasad, Pankaj; Mittal, Shivani Arora; Chongtham, Jonita; Mohanty, Sujata; Srivastava, Tapasya

    2017-06-01

    Activation of pluripotency regulatory circuit is an important event in solid tumor progression and the hypoxic microenvironment is known to enhance the stemness feature of some cells. The distinct population of cancer stem cells (CSCs)/tumor initiating cells exist in a niche and augment invasion, metastasis, and drug resistance. Previously, studies have reported global hypomethylation and site-specific aberrant methylation in gliomas along with other epigenetic modifications as important contributors to genomic instability during glioma progression. Here, we have demonstrated the role of hypoxia-mediated epigenetic modifications in regulating expression of core pluripotency factors, OCT4 and NANOG, in glioma cells. We observe hypoxia-mediated induction of demethylases, ten-eleven-translocation (TET) 1 and 3, but not TET2 in our cell-line model. Immunoprecipitation studies reveal active demethylation and direct binding of TET1 and 3 at the Oct4 and Nanog regulatory regions. Tet1 and 3 silencing assays further confirmed induction of the pluripotency pathway involving Oct4, Nanog, and Stat3, by these paralogues, although with varying degrees. Knockdown of Tet1 and Tet3 inhibited the formation of neurospheres in hypoxic conditions. We observed independent roles of TET1 and TET3 in differentially regulating pluripotency and differentiation associated genes in hypoxia. Overall, this study demonstrates an active demethylation in hypoxia by TET1 and 3 as a mechanism of Oct4 and Nanog overexpression thus contributing to the formation of CSCs in gliomas. Stem Cells 2017;35:1468-1478. © 2017 AlphaMed Press.

  15. Secretome Analysis of an Osteogenic Prostate Tumor Identifies Complex Signaling Networks Mediating Cross-talk of Cancer and Stromal Cells Within the Tumor Microenvironment*

    PubMed Central

    Lee, Yu-Chen; Gajdosik, Martina Srajer; Josic, Djuro; Clifton, James G.; Logothetis, Christopher; Yu-Lee, Li-Yuan; Gallick, Gary E.; Maity, Sankar N.; Lin, Sue-Hwa

    2015-01-01

    A distinct feature of human prostate cancer (PCa) is the development of osteoblastic (bone-forming) bone metastases. Metastatic growth in the bone is supported by factors secreted by PCa cells that activate signaling networks in the tumor microenvironment that augment tumor growth. To better understand these signaling networks and identify potential targets for therapy of bone metastases, we characterized the secretome of a patient-derived xenograft, MDA-PCa-118b (PCa-118b), generated from osteoblastic bone lesion. PCa-118b induces osteoblastic tumors when implanted either in mouse femurs or subcutaneously. To study signaling molecules critical to these unique tumor/microenvironment-mediated events, we performed mass spectrometry on conditioned media of isolated PCa-118b tumor cells, and identified 26 secretory proteins, such as TGF-β2, GDF15, FGF3, FGF19, CXCL1, galectins, and β2-microglobulin, which represent both novel and previously published secreted proteins. RT-PCR using human versus mouse-specific primers showed that TGFβ2, GDF15, FGF3, FGF19, and CXCL1 were secreted from PCa-118b cells. TGFβ2, GDF15, FGF3, and FGF19 function as both autocrine and paracrine factors on tumor cells and stromal cells, that is, endothelial cells and osteoblasts. In contrast, CXCL1 functions as a paracrine factor through the CXCR2 receptor expressed on endothelial cells and osteoblasts. Thus, our study reveals a complex PCa bone metastasis secretome with paracrine and autocrine signaling functions that mediate cross-talk among multiple cell types within the tumor microenvironment. PMID:25527621

  16. MAPK/FoxA2-mediated cigarette smoke-induced squamous metaplasia of bronchial epithelial cells.

    PubMed

    Du, Chunling; Lu, Jinchang; Zhou, Lei; Wu, Bo; Zhou, Feng; Gu, Liang; Xu, Donghui; Sun, Yingxin

    2017-01-01

    To explore the effect of cigarette smoke (CS) on the development of squamous metaplasia in human airway epithelial cells and the role of MAPK- and FoxA2-signaling pathways in the process. In an in vitro study, we treated the bronchial epithelial cell line BEAS2B with CS extract, followed by treatment with the ERK inhibitor U0126, the JNK inhibitor SP600125, or the p38 inhibitor SB203580. In vivo, we used a CS-induced rat model. After treatment with CS with or without MAPK inhibitors for 90 days, lung tissues were harvested. p-ERK, p-p38 and p-JNK protein levels in cells and lung tissue were measured using enzyme-linked immunosorbent assays, mRNA- and protein-expression profiles of FoxA2, E-cadherin, CD44, and ZO1 were measured using quantitative real-time polymerase chain reaction and Western blotting, respectively, and morphological changes in bronchial epithelial cells were observed using lung-tissue staining. In both the in vitro and in vivo studies, phosphorylation of the ERK1/2, JNK, and p38 proteins was significantly increased ( P <0.05) and mRNA and protein expression of E-cadherin and FoxA2 significantly decreased ( P <0.05) compared with the control group. ERK, JNK, and p38 inhibitors reversed the CS-extract-induced changes in E-cadherin, CD44, and ZO1 mRNA and protein expression ( P <0.05), decreased p-ERK, p-p38, and p-JNK protein levels in cells and lung tissue, suppressed bronchial epithelial hyperplasia and local squamous metaplasia, and decreased FoxA2 expression. MAPK and FoxA2 mediate CS-induced squamous metaplasia. MAPK inhibitors upregulate FoxA2, resulting in a reduction in the degree of squamous metaplasia.

  17. Melanoma-associated fibroblasts decrease tumor cell susceptibility to NK cell-mediated killing through matrix-metalloproteinases secretion

    PubMed Central

    Ziani, Linda; Safta-Saadoun, Thouraya Ben; Gourbeix, Johanne; Cavalcanti, Andrea; Robert, Caroline; Favre, Gilles; Chouaib, Salem; Thiery, Jerome

    2017-01-01

    Cancer-associated fibroblasts (CAFs) play a central role in the complex process of tumor-stroma interaction and promote tumor growth. Emerging evidences also suggest that these fibroblasts are involved in the alteration of the anti-tumor immune response by impacting several immune cell populations, especially through their secretion of pro-inflammatory and immunosuppressive factors in the tumor microenvironment. However, the underlying immuno-modulating mechanisms triggered by these fibroblasts are still only partially defined. In this study, we provide evidence that melanoma-associated fibroblasts decrease the susceptibility of melanoma tumor cells to NK-mediated lysis through the secretion of active matrix metalloproteinases. This secretion reduces the expression of the two NKG2D ligands, MICA/B, at the surface of tumor cells and consequently decreases the NKG2D-dependent cytotoxic activity of NK cells against melanoma tumor cells. Together, our data demonstrate that the modification of tumor cell susceptibility to killer cells is an important determinant of the anti-tumor immune response alteration triggered by CAFs. PMID:28423623

  18. Ultrasound-Mediated Tumor Imaging and Nanotherapy using Drug Loaded, Block Copolymer Stabilized Perfluorocarbon Nanoemulsions

    PubMed Central

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

    2011-01-01

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

  19. [Influence of pre-operational medicated dachengqi granule on inflammatory mediator in tumor patients].

    PubMed

    Wang, S; Qi, Q

    1999-06-01

    To find a simple, effective, with few side effect method of pre-cleaning intestine for surgical operation of abdominal malignancy. Thirty-five patients of abdominal malignant tumor were divided into two groups randomly and treated with Dachengqi Granule (DCQG) and routine western management (including oral taking antibiotics and enema with soap solution) respectively. Serum level of nitric oxide (NO), tumor necrosis factor (TNF), intercellular adhesive molecule-1 (ICAM-1), and enteric function recovering of patients were observed before operation, and 1, 3 and 7 days after operation. Time of borborygmus recovering and gas discharging after operation in the DCQG group was earlier than that of the control group, P < 0.05. Serum NO level was raised in both groups after operation, and reaching peak level at 3rd day post-operationally, as compared with pre-operation, P < 0.05, the difference between the two groups was insignificant. Serum TNF level lowered in both groups, but more apparent in the DCQG group, the inter-group difference was significant at the first day of operation, P < 0.05. Serum ICAM-1 level in the DCQG group decreased at the day 3 after operation with significant difference in comparison with pre-operational level, P < 0.05, but in the control group, change of ICAM-1 before and after operation was insignificant. The mean ICAM-1 level of the DCQG group at the day 3 post-operationally was significantly lower than that of the control group, P < 0.05. Compared with the routine management of western medicine, using DCQG for intestine pre-cleaning before operation could obviously lower the operation induced inflammatory reaction of tumor patients, reduce the secretion of inflammatory mediator, improve the recovery of enteric function and reduce the post-operational complication. Therefore, applying DCQG for pre-operational enteric preparing could provide a satisfactory effect in surgical operation of abdominal malignancy.

  20. Cathepsin B facilitates Autophagy mediated apoptosis in SPARC Overexpressed Primitive Neuroectodermal Tumor cells

    PubMed Central

    Bhoopathi, Praveen; Chetty, Chandramu; Gujrati, Meena; Dinh, Dzung H.; Rao, Jasti S.; Lakka, Sajani

    2011-01-01

    Medulloblastoma and neuroblastoma belong to a group of neoplasms designated as primitive neuroectodermal tumors (PNETs). Secreted Protein, Acidic and Rich in Cysteine (SPARC) is a matrix-associated glycoprotein that influences a variety of cellular activities in vitro and in vivo. Here, we provide evidence that expression of SPARC cDNA induces autophagy in PNET cells followed by apoptotic cell death. SPARC-induced autophagy was morphologically characterized by (i) the formation of membrane-bound autophagic vacuoles (AVO), (ii) increase in the levels of microtubule-associated protein light chain 3 (LC3) and (iii) induction of the lysososmal enzyme cathepsin B. Cathepsin B, in turn induced mitochondrial release of cytochrome c and activated caspase-3, events that signify the onset of apoptotic cell death. In agreement with these observations, inhibition of autophagy by 3-MA reduced AVO formation and LC3 and inhibited apoptosis, suggesting that autophagy plays a role in SPARC-mediated apoptosis. Blocking cathepsin B expression with a specific inhibitor of cathepsin B suppressed apoptosis but did not affect autophagy, which suggests that cathepsin B is a molecular link between autophagy and apoptosis. In summary, these findings demonstrate that SPARC expression induces autophagy, which results in the elevation of cathepsin B and subsequent mitochondria-mediated apoptosis. PMID:20339379

  1. Role of tumor-associated macrophages (TAM) in advanced gastric carcinoma: the impact on FasL-mediated counterattack.

    PubMed

    Ohno, Satoshi; Inagawa, Hiroyuki; Dhar, Dipok Kumar; Fujii, Toshiyuki; Ueda, Shuhei; Tachibana, Mitsuo; Ohno, Yumiko; Suzuki, Nobutaka; Inoue, Masaki; Soma, Gen-Ichiro; Nagasue, Naofumi

    2005-01-01

    Exactly what role does tumor-derived Fas ligand (FasL) play in cancer: maintaining the immune privilege site or inducing a pro-inflammatory effect? One possible hypothesis is that tumor-associated macrophages (TAM) act as the mediator that enables apoptosis of anti-tumor immune cells without FasL-related inflammation. We have evaluated the tumor FasL expression and TAM along the tumor margin and/or in cancer stroma, and their impact on the infiltration of immune-competent cells into the tumor nest. Tissue specimens from consecutive 84 advanced gastric carcinoma patients, who had undergone a curative resection, were evaluated for TAM (CD68+ cells), tumor FasL expression and immune status (CD8 + T cells). A high number of TAM significantly correlated with lymph node metastasis, intestinal type tumor and FasL expression. Although TAM had a tendency for an inverse correlation with the number of CD8+ T cells within the tumor nest (nest CD8) (p=0.0592), there was no correlation between FasL expression and nest CD8 (p=0.2158). This inverse association was found to be stronger in cases with both FasL-positive and high TAM tumors than in others (p=0.0139). The combination parameter of FasL-positive and high TAM became an independent prognostic factor in Cox's multivariate analysis, along with the pT status, nest CD8 and tumor cell apoptosis. We suggest that TAM works harmoniously with tumor-derived FasL and serves as a barrier against the infiltration of CD8+ T cells into the cancer nest.

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

    PubMed Central

    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

  3. Growth factor progranulin blocks tumor necrosis factor-α-mediated inhibition of osteoblast differentiation.

    PubMed

    Wang, N; Zhang, J; Yang, J X

    2016-09-09

    Tumor necrosis factor-α (TNF-α) stimulates osteoclast differentiation and suppresses osteoblast differentiation, leading to bone loss and decreased bone mass in local inflammation areas in patients with rheumatoid arthritis. The growth factor progranulin (PGRN) is expressed in various types of cells and play crucial roles in the pathogenesis of atherosclerosis and arthritis by blocking TNF-α. Here, we investigated the role of PGRN in blocking TNF-α-mediated inhibition of osteoblast differentiation and the regulatory mechanism. C2C12 stem cell was induced by bone morphogenetic protein-2 (BMP-2) for osteoblast differentiation. A significant increase in ALP activity (P < 0.001), as well as the expression of ColI, Ocn, and Bsp in the induced cells (P < 0.01 and P < 0.001) were observed; the marker gene expression and ALP activity were inhibited by TNF-α (P < 0.01 and P < 0.001). PGRN significantly blocks the TNF-α-mediated inhibition of osteoblast differentiation, evidenced by the ALP activity (P < 0.05 and P < 0.01), Alizarin red staining, the expression of ColI, Ocn, and Bsp (P < 0.05 and P < 0.01) and the osteoblast key transcription factor gene Runx2 (P < 0.01), Osx (P < 0.05), and ATF4 (P < 0.05). Mechanical study indicated that PGRN significantly blocks the TNF-α-mediated stimulation of NF-kB signaling (P < 0.01 and P < 0.001). PGRN exerts a protective effect on osteoblast differentiation in an inflammatory environment. Thus, we concluded that the treatment of osteoblasts with PGRN could be used in the future to prevent or treat rheumatoid arthritis-associated bone loss.

  4. Laser photobiomodulation of pro-inflammatory mediators on Walker Tumor 256 induced rats.

    PubMed

    Petrellis, Maria Carla; Frigo, Lúcio; Marcos, Rodrigo Labat; Pallotta, Rodney Capp; de Carvalho, Maria Helena Catelli; Muscará, Marcelo Nicolás; Maria, Durvanei Augusto; Lopes-Martins, Rodrigo Álvaro Brandão

    2017-12-01

    Laser photobiomodulation or low-level laser therapy (LLLT) is recognized worldwide for its expansive use in medicine. LLLT has been reported to increase enzymatic activity, increasing the mitochondrial transmembrane potential, leading to an increased energy availability and signal transduction. Nevertheless, an inhibitory effect is also observed by the production of excessive ROS which can result the shutdown of mitochondrial energy production, and finally to apoptosis. However, the mechanism of apoptosis induced by LLLT is still not well understood. The main objective of the present study was to investigate the hypothesis that LLLT induces oxidative stress and stimulates the generation of pro-inflammatory markers interfering in tumor progression. Seventy-two female Walker Tumor induced Wistar rats (eight weeks of age, 200g body weight) were used for this study. TW-256 cells were suspended in phosphate buffered saline and then subcutaneously inoculated at 1×107viabletumorcells/ml per rat into the right flank (tumor-bearing rats). After a period of 14days in order to assess the development of the solid tumor mass, the animals were randomized and distributed in four groups (n=8 animals/group): (1) Control or irradiated by LLLT (2) Laser 1J - 35,7J/cm 2 , (3) Laser 3J - 107,14J/cm 2 and (4) Laser 6J - 214,28J/cm 2 ; (Thera Laser - 660nm, 100mW DMC®, São Carlos, Brazil) at four equidistant points according to their respective treatment groups, conducted three times on alternate days. The regulation and expression of inflammatory mediators IL-1β, IL-6, IL-10, TNF-α was assessed by ELISA and gene expression of COX-1, COX-2, iNOS, eNOS was analyzed by RT-PCR. We found that the 1Joule (J) treated group promoted a significant increase in the levels of different inflammatory markers IL-1β, the gene expression of COX-2, iNOS, which was statistically different (p<0.05) when compared among different treatment and control groups. With Respect IL-6, IL-10, TNF-α levels

  5. Au@Pt nanoparticles as catalase mimics to attenuate tumor hypoxia and enhance immune cell-mediated cytotoxicity

    NASA Astrophysics Data System (ADS)

    Liang, Hong; Wu, Ying; Ou, Xiang-Yu; Li, Jing-Ying; Li, Juan

    2017-11-01

    Hypoxic tumor microenvironment (TME) is closely linked to tumor progression, heterogeneity and immune suppression. Therefore, the development of effective methods to overcome hypoxia and substantially enhance the immunotherapy efficacy remains a desirable goal. Herein, we engineered a biocompatible Au core/Pt shell nanoparticles (Au@Pt NPs) to reoxygenate the TME by reacting with endogenous H2O2. Treatment with Au@Pt NPs appeared to improve oxygen in intracellular environments and decrease hypoxia-inducible factor-1α expression. Furthermore, the integration of high catalytic efficiency of Au@Pt NPs with cytokine-induced killer (CIK) cell immunotherapy, could lead to significantly improve the effect of CIK cell-mediated cytotoxicity. These results suggest great potential of Au@Pt NPs for regulation of the hypoxic TME and enhance immune cell mediated anti-tumor immunity.

  6. Modulation of in Vivo Tumor Radiation Response via Gold Nanoshell-Mediated Vascular-Focused Hyperthermia: Characterizing an Integrated Antihypoxic and Localized Vascular Disrupting Targeting Strategy

    PubMed Central

    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

    2014-01-01

    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

  7. Social Competence in Childhood Brain Tumor Survivors: Feasibility and Preliminary Outcomes of a Peer-Mediated Intervention

    PubMed Central

    Devine, Katie A.; Bukowski, William M.; Sahler, Olle Jane Z.; Ohman-Strickland, Pamela; Smith, Tristram H.; Lown, E. Anne; Patenaude, Andrea Farkas; Korones, David N.; Noll, Robert B.

    2016-01-01

    Objective Evaluate the acceptability, feasibility, and preliminary outcomes of a peer-mediated intervention to improve social competence of brain tumor survivors and classmates. Methods Twelve childhood brain tumor survivors and 217 classroom peers in intervention (n = 8) or comparison (n = 4) classrooms completed measures of social acceptance and reputation at two time points in the year. The intervention (5–8 sessions over 4–6 weeks) taught peer leaders skills for engaging classmates. Individual and classroom outcomes were analyzed with ANCOVA. Results Recruitment rates of families of brain tumor survivors (81%) and schools (100%) were adequate. Peer leaders reported satisfaction with the intervention. Preliminary outcome data trended toward some benefit in increasing the number of friend nominations for survivors of brain tumors but no changes in other peer-reported metrics. Preliminary results also suggested some positive effects on classroom levels of victimization and rejection. Conclusions A peer-mediated intervention was acceptable to families of brain tumor survivors and feasible to implement in schools. Findings warrant a larger trial to evaluate improvements for children with brain tumors and their peers. PMID:27355881

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

    PubMed Central

    Kopechek, Jonathan A.; Park, Eunjoo; Mei, Chang-Sheng; McDannold, Nathan J.; Porter, Tyrone M.

    2014-01-01

    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. PMID:23502252

  9. Systemic tumor-targeted sodium iodide symporter (NIS) gene therapy of hepatocellular carcinoma mediated by B6 peptide polyplexes.

    PubMed

    Urnauer, Sarah; Klutz, Kathrin; Grünwald, Geoffrey K; Morys, Stephan; Schwenk, Nathalie; Zach, Christian; Gildehaus, Franz-Josef; Rödl, Wolfgang; Ogris, Manfred; Wagner, Ernst; Spitzweg, Christine

    2017-05-01

    Nonviral polymer-based gene transfer represents an adaptable system for tumor-targeted gene therapy because various design strategies of shuttle systems, together with the mechanistic concept of active tumor targeting, lead to improved gene delivery vectors resulting in higher tumor specificity, efficacy and safety. Using the sodium iodide symporter (NIS) as a theranostic gene, nonviral gene delivery vehicles based on linear polyethylenimine (LPEI), polyethylene glycol (PEG) and coupled to the synthetic peptide B6 (LPEI-PEG-B6), which specifically binds to tumor cells, were investigated in a hepatocellular carcinoma xenograft model for tumor selectivity and transduction efficiency. In vitro incubation of three different tumor cell lines with LPEI-PEG-B6/NIS resulted in significant increase in iodide uptake activity compared to untargeted and empty vectors. After establishment of subcutaneous HuH7 tumors, NIS-conjugated nanoparticles were injected intravenously followed by analysis of radioiodide biodistribution using 123 I-scintigraphy showing significant perchlorate-sensitive iodide accumulation in tumors of LPEI-PEG-B6/NIS-treated mice (8.0 ± 1.5% ID/g 123 I; biological half-life of 4 h). After four cycles of repetitive polyplex/ 131 I applications, a significant delay of tumor growth was observed, which was associated with markedly improved survival in the therapy group. These results clearly demonstrate that systemic in vivo NIS gene transfer using nanoparticle vectors coupled to B6 tumor targeting ligand is capable of inducing tumor-specific radioiodide uptake. This promising gene therapy approach opens the exciting prospect of NIS-mediated radionuclide therapy in metastatic cancer, together with the possibility of combining several targeting ligands to enhance selective therapeutic efficacy in a broad field of cancer types with various receptor expression profiles. Copyright © 2017 John Wiley & Sons, Ltd.

  10. High Affinity Binders to EphA2 Isolated from Abdurin Scaffold Libraries; Characterization, Binding and Tumor Targeting

    PubMed Central

    Ullman, Christopher; Mathonet, Pascale; Oleksy, Arkadiusz; Diamandakis, Agata; Tomei, Licia; Demartis, Anna; Nardi, Chiara; Sambucini, Sonia; Missineo, Antonino; Alt, Karen; Hagemeyer, Christoph E.; Harris, Matt; Hedt, Amos; Weis, Roland; Gehlsen, Kurt R.

    2015-01-01

    Abdurins are a novel antibody-like scaffold derived from the engineering of a single isolated CH2 domain of human IgG. Previous studies established the prolonged serum half-life of Abdurins, the result of a retained FcRn binding motif. Here we present data on the construction of large, diverse, phage-display and cell-free DNA display libraries and the isolation of high affinity binders to the cancer target, membrane-bound ephrin receptor tyrosine kinase class A2 (EphA2). Antigen binding regions were created by designing combinatorial libraries into the structural loops and Abdurins were selected using phage display methods. Initial binders were reformatted into new maturation libraries and low nanomolar binders were isolated using cell-free DNA display, CIS display. Further characterization confirmed binding of the Abdurins to both human and murine EphA2 proteins and exclusively to cell lines that expressed EphA2, followed by rapid internalization. Two different EphA2 binders were labeled with 64Cu, using a bifunctional MeCOSar chelator, and administered to mice bearing tumors from transplanted human prostate cancer cells, followed by PET/CT imaging. The anti-EphA2 Abdurins localized in the tumors as early as 4 hours after injection and continued to accumulate up to 48 hours when the imaging was completed. These data demonstrate the ability to isolate high affinity binders from the engineered Abdurin scaffold, which retain a long serum half-life, and specifically target tumors in a xenograft model. PMID:26313909

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

    SciTech Connect

    Rattigan, Yanique I.; Patel, Brijesh B.; 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

    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,more » 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.« less

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

    PubMed Central

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

    2012-01-01

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

  13. Nitric oxide mediates insect cellular immunity via phospholipase A2 activation

    USDA-ARS?s Scientific Manuscript database

    After infection or invasion is recognized, biochemical mediators act in signaling insect immune functions. These include biogenic amines, insect cytokines, eicosanoids and nitric oxide (NO). Treating insects or isolated hemocyte populations with different mediators often leads to similar results. Se...

  14. Chemotherapy-Induced IL34 Enhances Immunosuppression by Tumor-Associated Macrophages and Mediates Survival of Chemoresistant Lung Cancer Cells.

    PubMed

    Baghdadi, Muhammad; Wada, Haruka; Nakanishi, Sayaka; Abe, Hirotake; Han, Nanumi; Putra, Wira Eka; Endo, Daisuke; Watari, Hidemichi; Sakuragi, Noriaki; Hida, Yasuhiro; Kaga, Kichizo; Miyagi, Yohei; Yokose, Tomoyuki; Takano, Atsushi; Daigo, Yataro; Seino, Ken-Ichiro

    2016-10-15

    The ability of tumor cells to escape immune destruction and their acquired resistance to chemotherapy are major obstacles to effective cancer therapy. Although immune checkpoint therapies such as anti-PD-1 address these issues in part, clinical responses remain limited to a subpopulation of patients. In this report, we identified IL34 produced by cancer cells as a driver of chemoresistance. In particular, we found that IL34 modulated the functions of tumor-associated macrophages to enhance local immunosuppression and to promote the survival of chemoresistant cancer cells by activating AKT signaling. Targeting IL34 in chemoresistant tumors resulted in a remarkable inhibition of tumor growth when accompanied with chemotherapy. Our results define a pathogenic role for IL34 in mediating immunosuppression and chemoresistance and identify it as a tractable target for anticancer therapy. Cancer Res; 76(20); 6030-42. ©2016 AACR. ©2016 American Association for Cancer Research.

  15. Polyclonal HER2-specific antibodies induced by vaccination mediate receptor internalization and degradation in tumor cells.

    PubMed

    Ren, Xiu-Rong; Wei, Junping; Lei, Gangjun; Wang, Jiangbo; Lu, Jiuyi; Xia, Wenle; Spector, Neil; Barak, Larry S; Clay, Timothy M; Osada, Takuya; Hamilton, Erika; Blackwell, Kimberly; Hobeika, Amy C; Morse, Michael A; Lyerly, H Kim; Chen, Wei

    2012-06-07

    Sustained HER2 signaling at the cell surface is an oncogenic mechanism in a significant proportion of breast cancers. While clinically effective therapies targeting HER2 such as mAbs and tyrosine kinase inhibitors exist, tumors overexpressing HER2 eventually progress despite treatment. Thus, abrogation of persistent HER2 expression at the plasma membrane to synergize with current approaches may represent a novel therapeutic strategy. We generated polyclonal anti-HER2 antibodies (HER2-VIA) by vaccinating mice with an adenovirus expressing human HER2, and assessed their signaling effects in vitro and anti-tumor effects in a xenograft model. In addition, we studied the signaling effects of human HER2-specific antibodies induced by vaccinating breast cancer patients with a HER2 protein vaccine. HER2-VIA bound HER2 at the plasma membrane, initially activating the downstream kinases extracellular signal-regulated protein kinase 1/2 and Akt, but subsequently inducing receptor internalization in clathrin-coated pits in a HER2 kinase-independent manner, followed by ubiquitination and degradation of HER2 into a 130 kDa fragment phosphorylated at tyrosine residues 1,221/1,222 and 1,248. Following vaccination of breast cancer patients with the HER2 protein vaccine, HER2-specific antibodies were detectable and these antibodies bound to cell surface-expressed HER2 and inhibited HER2 signaling through blocking tyrosine 877 phosphorylation of HER2. In contrast to the murine antibodies, human anti-HER2 antibodies induced by protein vaccination did not mediate receptor internalization and degradation. These data provide new insight into HER2 trafficking at the plasma membrane and the changes induced by polyclonal HER2-specific antibodies. The reduction of HER2 membrane expression and HER2 signaling by polyclonal antibodies induced by adenoviral HER2 vaccines supports human clinical trials with this strategy for those breast cancer patients with HER2 therapy-resistant disease.

  16. Nicotine-mediated cell proliferation and tumor progression in smoking-related cancers

    PubMed Central

    Schaal, Courtney; Chellappan, Srikumar P.

    2014-01-01

    Tobacco smoke contains multiple classes of established carcinogens including benzo(a)pyrenes, polycyclic aromatic hydrocarbons, and tobacco specific nitrosamines. Most of these compounds exert their genotoxic effects by forming DNA adducts and generation of reactive oxygen species, causing mutations in vital genes like K-Ras and p53. In addition, tobacco specific nitrosamines can activate nicotinic acetylcholine receptors (nAChRs) and to a certain extent β-Adrenergic receptors (β-ARs), promoting cell proliferation. Further, it has been demonstrated that nicotine, the major addictive component of tobacco smoke, can induce cell cycle progression, angiogenesis, and metastasis of lung and pancreatic cancers. These effects occur mainly through the α7-nAChRs, with possible contribution from the β-ARs and/or epidermal growth factor receptors (EGFRs). This review article will discuss the molecular mechanisms by which nicotine and its oncogenic derivatives such as NNK (4-methylnitrosamino)-1-(3-pyridyl)-1-butanone) and NNN (N-nitrosonornicotine) induce cell cycle progression and promote tumor growth. A variety of signaling cascades are induced by nicotine through nAChRs, including the MAPK/ERK pathway, PI3K/AKT pathway and JAK/STAT signaling. In addition, studies have shown that nAChR activation induces Src kinase in a β-arrestin-1 dependent manner, leading to the inactivation of Rb protein and resulting in the expression of E2F1-regulated proliferative genes. Such nAChR-mediated signaling events enhance the proliferation of cells and render them resistant to apoptosis induced by various agents. These observations highlight the role of nAChRs in promoting the growth and metastasis of tumors and raise the possibility of targeting them for cancer therapy. PMID:24398389

  17. Silencing receptor EphA2 induces apoptosis and attenuates tumor growth in malignant mesothelioma

    PubMed Central

    Mohammed, Kamal A; Wang, Xiaohong; Goldberg, Eugene P; Antony, Veena B; Nasreen, Najmunnisa

    2011-01-01

    Receptor EphA2 over-expression is associated with the aggressive nature of growth in malignant mesothelioma (MM) and silencing EphA2 with interference RNA suppressed MM proliferation. The mechanisms associated with targeting the EphA2 gene in MM were not clear. We sought to determine whether silencing EphA2 induces apoptosis in MM cells by either extrinsic or intrinsic pathways. The receptor EphA2 signaling pathway may provide attractive therapeutic strategy for MM. Apoptosis was determined by Cell Death ELISA in MM Cells transfected with siRNA-EphA2 and control siRNA. The gene expression profile of apoptosis pathways were analyzed by GEArray. Selected genes were further studied by quantitative PCR, Western analysis, and immunofluorescence. Caspases activities were measured by fluorescence spectrometer. Silencing EphA2 expression induced apoptosis in MMC. Apoptosis was characterized by FADD expression, activated caspase-8, caspase-3 and induction of Bax, Bak, and Bid as revealed by GEArray and protein fractionation assays. The expression of FADD, Bid, caspase-8, cytochrome-c and apaf-1 were significantly higher in the cytosolic fractions of EphA2-siRNA transfected cells. Furthermore, blocking the expression of caspase-8 by an inhibitor blunted FADD expression, indicating that caspase-8 is implicated in EphA2-siRNA induced apoptosis in MMC. Our data indicates that targeting the EphA2 gene by siRNA induced both extrinsic and intrinsic apoptotic pathways in MM Cells. Receptor EphA2 inhibition may be an effective approach for inhibiting MM growth and a promising direction for MM therapy. PMID:21968554

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

    PubMed

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

    2017-06-13

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

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

    PubMed Central

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

    2017-01-01

    Increased glycolysis and overexpression of glucose transporters (GLUTs) are physiological characteristics of human malignancies. Based on the so-called Warburg effect, 18flurodeoxyglucose-positron emission tomography (FDG-PET) has successfully developed as clinical modality for the diagnosis and staging of many cancers. To leverage this glucose transporter mediated metabolic disparity between normal and malignant cells, in the current report, we focus on the fluorine substituted series of glucose, mannose and galactose-conjugated (trans-R,R-cyclohexane-1,2-diamine)-2-flouromalonato-platinum(II) complexes for a comprehensive evaluation on their selective tumor targeting. Besides highly improved water solubility, these sugar-conjugates presented improved cytotoxicity than oxaliplatin in glucose tranporters (GLUTs) overexpressing cancer cell lines and exhibited no cross-resistance to cisplatin. For the highly water soluble glucose-conjugated complex (5a), two novel in vivo assessments were conducted and the results revealed that 5a was more efficacious at a lower equitoxic dose (70% MTD) than oxaliplatin (100% MTD) in HT29 xenograft model, and it was significantly more potent than oxaliplatin in leukemia-bearing DBA/2 mice as well even at equimolar dose levels (18% vs 90% MTD). GLUT inhibitor mediated cell viability analysis, GLUT1 knockdown cell line-based cytotoxicity evaluation, and platinum accumulation study demonstrated that the cellular uptake of the sugar-conjugates was regulated by GLUT1. The higher intrinsic DNA reactivity of the sugar-conjugates was confirmed by kinetic study of platinum(II)-guanosine adduct formation. The mechanistic origin of the antitumor effect of the fluorine complexes was found to be forming the bifunctional Pt-guanine-guanine (Pt-GG) intrastrand cross-links with DNA. The results provide a rationale for Warburg effect targeted anticancer drug design. PMID:28467806

  20. Inhibition of cyclooxygenase-2 aggravates secretory phospholipase A2-mediated progression of acute liver injury.

    PubMed

    Bhave, Vishakha S; Donthamsetty, Shashikiran; Latendresse, John R; Mehendale, Harihara M

    2008-04-15

    Our previous study [Bhave, V. S., Donthamsetty, S., Latendresse, J. R., Muskhelishvili, L., and Mehendale, H. M. 2008-this issue. Secretory phospholipase A(2) mediates progression of acute liver injury in the absence of sufficient COX-2. Toxicol Appl Pharmacol] showed that in the absence of sufficient induction and co-presence of cyclooxygenase-2 (COX-2), secretory phospholipase A(2) (sPLA(2)) appearing in the intercellular spaces for cleanup of post-necrotic debris seems to contribute to the progression of toxicant-initiated liver injury, possibly by hydrolysis of membrane phospholipids of hepatocytes in the perinecrotic areas. To further test our hypothesis on the protective role of COX-2, male Fisher-344 rats were administered a selective COX-2 inhibitor, NS-398, and then challenged with a moderately toxic dose of CCl(4). This led to a 5-fold increase in the susceptibility of the COX-2 inhibited rats to CCl(4) hepatotoxicity and mortality. The CCl(4) bioactivating enzyme CYP2E1 protein, CYP2E1 enzyme activity, and the (14)CCl(4)-derived radiolabel covalently bound to the liver proteins were unaffected by the COX-2 inhibitor suggesting that the increased hepatotoxic sensitivity of the COX-2 inhibited rats was not due to higher bioactivation of CCl(4). Further investigation showed that this increased mortality was due to higher plasma and hepatic sPLA(2) activities, inhibited PGE(2) production, and progression of liver injury as compared to the non-intervened rats(.) In conclusion, inhibition of COX-2 mitigates the tissue protective mechanisms associated with COX-2 induction, which promotes sPLA(2)-mediated progression of liver injury in an acute liver toxicity model. Because increased sPLA(2) activity in the intercellular space is associated with increased progression of injury, and induced COX-2 is associated with hepatoprotection, ratios of hepatic COX-2 and sPLA(2) activities may turn out to be a useful tool in predicting the extent of hepatotoxicities.

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

    NASA Astrophysics Data System (ADS)

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

    2017-06-01

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

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

    PubMed

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

    2017-02-28

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

  3. Splicing function of mitotic regulators links R-loop–mediated DNA damage to tumor cell killing

    PubMed Central

    Wan, Yihan; Zheng, Xiaobin; Chen, Haiyang; Guo, Yuxuan; Jiang, Hao; He, Xiaonan

    2015-01-01

    Although studies suggest that perturbing mitotic progression leads to DNA damage and p53 activation, which in turn lead to either cell apoptosis or senescence, it remains unclear how mitotic defects trigger p53 activation. We show that BuGZ and Bub3, which are two mitotic regulators localized in the interphase nucleus, interact with the splicing machinery and are required for pre-mRNA splicing. Similar to inhibition of RNA splicing by pladienolide B, depletion of either BuGZ or Bub3 led to increased formation of RNA–DNA hybrids (R-loops), which led to DNA damage and p53 activation in both human tumor cells and primary cells. Thus, R-loop–mediated DNA damage and p53 activation offer a mechanistic explanation for apoptosis of cancer cells and senescence of primary cells upon disruption of the dual-function mitotic regulators. This demonstrates the importance of understanding the full range of functions of mitotic regulators to develop antitumor drugs. PMID:25918225

  4. Fer tyrosine kinase oligomer mediates and amplifies Src-induced tumor progression.

    PubMed

    Oneyama, C; Yoshikawa, Y; Ninomiya, Y; Iino, T; Tsukita, S; Okada, M

    2016-01-28

    c-Src is upregulated in various human cancers, suggesting its role in malignant progression. However, the molecular circuits of c-Src oncogenic signaling remain elusive. Here we show that Fer tyrosine kinase oligomer mediates and amplifies Src-induced tumor progression. Previously, we showed that transformation of fibroblasts is promoted by the relocation of c-Src to non-raft membranes. In this study, we identified Fer and ezrin as non-raft c-Src targets. c-Src directly activated Fer by initiating its autophosphorylation, which was further amplified by Fer oligomerization. Fer interacted with active c-Src at focal adhesion membranes and activated Fer-phosphorylated ezrin to induce cell transformation. Fer was also crucial for cell transformation induced by v-Src or epidermal growth-factor receptor activation. Furthermore, Fer activation was required for tumorigenesis and invasiveness in some cancer cells in which c-Src is upregulated. We propose that the Src-Fer axis represents a new therapeutic target for treatment of a subset of human cancers.

  5. Role of CYP epoxygenases in A2A AR-mediated relaxation using A2A AR-null and wild-type mice.

    PubMed

    Nayeem, Mohammed A; Poloyac, Samuel M; Falck, John R; Zeldin, Darryl C; Ledent, Catherine; Ponnoth, Dovenia S; Ansari, Habib R; Mustafa, S Jamal

    2008-11-01

    We hypothesized that A2A adenosine receptor (A2A AR) activation causes vasorelaxation through cytochrome P-450 (CYP) epoxygenases and endothelium-derived hyperpolarizing factors, whereas lack of A2A AR activation promotes vasoconstriction through Cyp4a in the mouse aorta. Adenosine 5'-N-ethylcarboxamide (NECA; 10(-6) M), an adenosine analog, caused relaxation in wild-type A2A AR (A2A AR+/+; +33.99 +/- 4.70%, P < 0.05) versus contraction in A2A AR knockout (A2A AR(-/-); -27.52 +/- 4.11%) mouse aortae. An A2A AR-specific antagonist (SCH-58261; 1 microM) changed the NECA (10(-6) M) relaxation response to contraction (-35.82 +/- 4.69%, P < 0.05) in A2A AR+/+ aortae, whereas no effect was noted in A2A AR(-/-) aortae. Significant contraction was seen in the absence of the endothelium in A2A AR+/+ (-2.58 +/- 2.25%) aortae compared with endothelium-intact aortae. An endothelial nitric oxide synthase inhibitor (N-nitro-L-arginine methyl ester; 100 microM) and a cyclooxygenase inhibitor (indomethacin; 10 microM) failed to block NECA-induced relaxation in A2A AR+/+ aortae. A selective inhibitor of CYP epoxygenases (methylsulfonyl-propargyloxyphenylhexanamide; 10 microM) changed NECA-mediated relaxation (-22.74 +/- 5.11% at 10(-6) M) and CGS-21680-mediated relaxation (-18.54 +/- 6.06% at 10(-6) M) to contraction in A2A AR+/+ aortae, whereas no response was noted in A2A AR(-/-) aortae. Furthermore, an epoxyeicosatrienoic acid (EET) antagonist [14,15-epoxyeicosa-5(Z)-enoic acid; 10 microM] was able to block NECA-induced relaxation in A2A AR+/+ aortae, whereas omega-hydroxylase inhibitors (10 microM dibromo-dodecenyl-methylsulfimide and 10 microM HET-0016) changed contraction into relaxation in A2A AR(-/-) aorta. Cyp2c29 protein was upregulated in A2A AR+/+ aortae, whereas Cyp4a was upregulated in A2A AR(-/-) aortae. Higher levels of dihydroxyeicosatrienoic acids (DHETs; 14,15-DHET, 11,12-DHET, and 8,9-DHET, P < 0.05) were found in A2A AR+/+ versus A2A AR(-/-) aortae. EET levels

  6. Group 1B Phospholipase A2Mediated Lysophospholipid Absorption Directly Contributes to Postprandial Hyperglycemia

    PubMed Central

    Labonté, Eric D.; Kirby, R. Jason; Schildmeyer, Nicholas M.; Cannon, April M.; Huggins, Kevin W.; Hui, David Y.

    2007-01-01

    Postprandial hyperglycemia is an early indicator of abnormality in glucose metabolism leading to type 2 diabetes. However, mechanisms that contribute to postprandial hyperglycemia have not been identified. This study showed that mice with targeted inactivation of the group 1B phospholipase A2 (Pla2g1b) gene displayed lower postprandial glycemia than that observed in wild-type mice after being fed a glucose-rich meal. The difference was caused by enhanced postprandial glucose uptake by the liver, heart, and muscle tissues as well as altered postprandial hepatic glucose metabolism in the Pla2g1b−/ − mice. These differences were attributed to a fivefold decrease in the amount of dietary phospholipids absorbed as lysophospholipids in Pla2g1b−/− mice compared with that observed in Pla2g1b+/+ mice. Elevating plasma lysophospholipid levels in Pla2g1b−/− mice via intraperitoneal injection resulted in glucose intolerance similar to that exhibited by Pla2g1b+/+mice. Studies with cultured hepatoma cells revealed that lysophospholipids dose-dependently suppressed insulin-stimulated glycogen synthesis. These results demonstrated that reduction of lysophospholipid absorption enhances insulin-mediated glucose metabolism and is protective against postprandial hyperglycemia. PMID:16567514

  7. Carbonic anhydrase inhibitors. Design of fluorescent sulfonamides as probes of tumor-associated carbonic anhydrase IX that inhibit isozyme IX-mediated acidification of hypoxic tumors.

    PubMed

    Cecchi, Alessandro; Hulikova, Alzbeta; Pastorek, Jaromír; Pastoreková, Silvia; Scozzafava, Andrea; Winum, Jean-Yves; Montero, Jean-Louis; Supuran, Claudiu T

    2005-07-28

    Sulfonamides inhibit the catalytic activity of carbonic anhydrases (CAs, EC 4.2.1.1), enzymes participating in the regulation of acid-base balance and ion transport in many tissues. Carbonic anhydrase IX (CA IX), a transmembrane isoform with predominant association with tumors and limited distribution in normal tissues, is strongly overexpressed by hypoxia. Hypoxia increases the catalytic performance of CA IX contributing to microenvironmental acidosis, which influences cancer progression and treatment outcome. CA IX represents a target for detection and therapy of hypoxic tumors. Sulfonamide CA IX selective inhibitors accumulate only in hypoxic cells containing CA IX, reversing acidification mediated by this enzyme. The design of fluorescent sulfonamides that preferentially inhibit the activity of CA IX, showing reduced penetration through the plasma membranes and binding to hypoxic cells expressing CA IX, is reported here. These inhibitors represent promising candidates for developing anticancer therapies based on tumor-associated CA isozyme inhibition and offer interesting tools for imaging and further investigation of hypoxic tumors.

  8. Resistance of guinea-pig hepatoma cells to complement-mediated lysis induced by ascites fluid or serum from tumor-bearing animals.

    PubMed

    Abe, S; Berczi, I; Sehon, A H

    1977-10-15

    The mechanisms of tumor cell susceptibility and resistance to cytotoxic antibodies were investigated in the guinea-pig ascites hepatoma (line-1 and line-10) system. Treatment of line-specific rabbit antibody-coated tumor cells by ascitic fluid, by serum of tumor bearers or by tumor extract inhibited subsequent complement-mediated lysis. Inhibition by ascitic fluid and serum was not line-specific, but inhibition by tumor extract was line-specific. Treatment of tumor cells with ascitic fluid or tumor extract prior to exposure to specific cytotoxic antibody and complement did not inhibit lysis. Incubation of cytotoxic rabbit antisera with ascitic fluid, tumor-bearer serum or tumor extract neutralized their complement-dependent cytotoxic activity on tumor cells. Tumor-immune guinea-pigs exhibited line-specific delayed cutaneous reactions after injection with ascitic fluid or tumor extract. Studies with indrect immunofluorescence revealed that exposure to ascites fluid or tumor extract caused a rapid shedding of rabbit antibodies from the tumor cell surface. Evidence is presented indicating that the active fraction of ascites fluid was associated with immune complexes consisting of IgG and tumor antigen in excess. The relevance of these findings to tumor escape from immune destruction in vivo is discussed.

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

    PubMed

    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.

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

    PubMed Central

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

    2016-01-01

    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

  11. Complement is a central mediator of radiotherapy-induced tumor-specific immunity and clinical response.

    PubMed

    Surace, Laura; Lysenko, Veronika; Fontana, Andrea Orlando; Cecconi, Virginia; Janssen, Hans; Bicvic, Antonela; Okoniewski, Michal; Pruschy, Martin; Dummer, Reinhard; Neefjes, Jacques; Knuth, Alexander; Gupta, Anurag; van den Broek, Maries

    2015-04-21

    Radiotherapy induces DNA damage and cell death, but recent data suggest that concomitant immune stimulation is an integral part of the therapeutic action of ionizing radiation. It is poorly understood how radiotherapy supports tumor-specific immunity. Here we report that radiotherapy induced tumor cell death and transiently activated complement both in murine and human tumors. The local production of pro-inflammatory anaphylatoxins C3a and C5a was crucial to the tumor response to radiotherapy and concomitant stimulation of tumor-specific immunity. Dexamethasone, a drug frequently given during radiotherapy, limited complement activation and the anti-tumor effects of the immune system. Overall, our findings indicate that anaphylatoxins are key players in radiotherapy-induced tumor-specific immunity and the ensuing clinical responses. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. The natural dietary genistein boosts bacteriophage-mediated cancer cell killing by improving phage-targeted tumor cell transduction.

    PubMed

    Tsafa, Effrosyni; Al-Bahrani, Mariam; Bentayebi, Kaoutar; Przystal, Justyna; Suwan, Keittisak; Hajitou, Amin

    2016-08-09

    Gene therapy has long been regarded as a promising treatment for cancer. However, cancer gene therapy is still facing the challenge of targeting gene delivery vectors specifically to tumors when administered via clinically acceptable non-invasive systemic routes (i.e. intravenous). The bacteria virus, bacteriophage (phage), represents a new generation of promising vectors in systemic gene delivery since their targeting can be achieved through phage capsid display ligands, which enable them to home to specific tumor receptors without the need to ablate any native eukaryotic tropism. We have previously reported a tumor specific bacteriophage vector named adeno-associated virus/phage, or AAVP, in which gene expression is under a recombinant human rAAV2 virus genome targeted to tumors via a ligand-directed phage capsid. However, cancer gene therapy with this tumor-targeted vector achieved variable outcomes ranging from tumor regression to no effect in both experimental and natural preclinical models. Herein, we hypothesized that combining the natural dietary genistein, with proven anticancer activity, would improve bacteriophage anticancer safe therapy. We show that combination treatment with genistein and AAVP increased targeted cancer cell killing by AAVP carrying the gene for Herpes simplex virus thymidine kinase (HSVtk) in 2D tissue cultures and 3D tumor spheroids. We found this increased tumor cell killing was associated with enhanced AAVP-mediated gene expression. Next, we established that genistein protects AAVP against proteasome degradation and enhances vector genome accumulation in the nucleus. Combination of genistein and phage-guided virotherapy is a safe and promising strategy that should be considered in anticancer therapy with AAVP.

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

    PubMed Central

    Li, Qi-hui; Xie, Wen-xia; Li, Xiao-pei; Huang, Ka-te; Du, Zhong-heng; Cong, Wen-jie; Zhou, Long-hua; Ye, Tian-shen; Chen, Jiang-Fan

    2015-01-01

    To study the role of adenosine A2A receptor (A2AR) in mediating the anti-inflammatory effect of electroacupuncture (EA) on synovitis in collagen-induced arthritis (CIA), C57BL/6 mice were divided into five treatment groups: Sham-control, CIA-control, CIA-EA, CIA-SCH58261 (A2AR antagonist), and CIA-EA-SCH58261. All mice except those in the Sham-control group were immunized with collagen II for arthritis induction. EA treatment was administered using the stomach 36 and spleen 6 points, and stimulated with a continuous rectangular wave for 30 min daily. EA treatment and SCH58261 were administered daily from days 35 to 49 (n = 10). After treatment, X-ray radiography of joint bone morphology was established at day 60 and mouse blood was collected for ELISA determination of tumor necrosis factor alpha (TNF-α) levels. Mice were sacrificed and processed for histological examination of pathological changes of joint tissue, including hematoxylin-eosin staining and immunohistochemistry of A2AR expression. EA treatment resulted in significantly reduced pathological scores, TNF-α concentrations, and bone damage X-ray scores. Importantly, the anti-inflammatory and tissue-protective effect of EA treatment was reversed by coadministration of SCH58261. Thus, EA treatment exerts an anti-inflammatory effect resulting in significant protection of cartilage by activation of A2AR in the synovial tissue of CIA. PMID:25784951

  14. Reduced adenosine A2a receptor-mediated efferent arteriolar vasodilation contributes to diabetes-induced glomerular hyperfiltration.

    PubMed

    Persson, Patrik; Hansell, Peter; Palm, Fredrik

    2015-01-01

    Diabetes is associated with increased risk for development of kidney disease, and an increased glomerular filtration rate is an early indication of altered kidney function. Here we determine whether reduced adenosine A2a receptor-mediated vasodilation of the efferent arteriole contributes to the increased glomerular filtration rate in diabetes. The glomerular filtration rate, renal blood flow, and proximal tubular stop flow pressure were investigated in control and streptozotocin-diabetic rats during baseline and after administration of the adenosine A2a receptor antagonist ZM241385 or the adenosine A2a receptor agonist CGS21680. The diabetes-induced glomerular hyperfiltration was reduced by 24% following A2a receptor stimulation but was unaffected by A2a receptor inhibition. Contrarily, glomerular filtration rate in controls increased by 22% after A2a receptor inhibition and was unaffected by A2a stimulation. The increased glomerular filtration rate after A2a receptor inhibition in controls and decreased glomerular filtration rate after A2a receptor activation in diabetics were caused by increased and decreased stop flow pressure, respectively. None of the interventions affected renal blood flow. Thus, the normal adenosine A2a receptor-mediated tonic vasodilation of efferent arterioles is abolished in the diabetic kidney. This causes increased efferent arteriolar resistance resulting in increased filtration fraction and hyperfiltration.

  15. The p75{sup NTR} tumor suppressor induces cell cycle arrest facilitating caspase mediated apoptosis in prostate tumor cells

    SciTech Connect

    Khwaja, Fatima; Tabassum, Arshia; Allen, Jeff

    2006-03-24

    The p75 neurotrophin receptor (p75{sup NTR}) is a death receptor which belongs to the tumor necrosis factor receptor super-family of membrane proteins. This study shows that p75{sup NTR} retarded cell cycle progression by induced accumulation of cells in G0/G1 and a reduction in the S phase of the cell cycle. The rescue of tumor cells from cell cycle progression by a death domain deleted ({delta}DD) dominant-negative antagonist of p75{sup NTR} showed that the death domain transduced anti-proliferative activity in a ligand-independent manner. Conversely, addition of NGF ligand rescued retardation of cell cycle progression with commensurate changes in components of themore » cyclin/cdk holoenzyme complex. In the absence of ligand, p75{sup NTR}-dependent cell cycle arrest facilitated an increase in apoptotic nuclear fragmentation of the prostate cancer cells. Apoptosis of p75{sup NTR} expressing cells occurred via the intrinsic mitochondrial pathway leading to a sequential caspase-9 and -7 cascade. Since the death domain deleted dominant-negative antagonist of p75{sup NTR} rescued intrinsic caspase associated apoptosis in PC-3 cells, this shows p75{sup NTR} was integral to ligand independent induction of apoptosis. Moreover, the ability of ligand to ameliorate the p75{sup NTR}-dependent intrinsic apoptotic cascade indicates that NGF functioned as a survival factor for p75{sup NTR} expressing prostate cancer cells.« less

  16. Racial and Ethnic Differences in Breast Cancer Survival: Mediating Effect of Tumor Characteristics and Sociodemographic and Treatment Factors

    PubMed Central

    Warner, Erica T.; Tamimi, Rulla M.; Hughes, Melissa E.; Ottesen, Rebecca A.; Wong, Yu-Ning; Edge, Stephen B.; Theriault, Richard L.; Blayney, Douglas W.; Niland, Joyce C.; Winer, Eric P.; Weeks, Jane C.; Partridge, Ann H.

    2015-01-01

    Purpose To evaluate the relationship between race/ethnicity and breast cancer–specific survival according to subtype and explore mediating factors. Patients and Methods Participants were women presenting with stage I to III breast cancer between January 2000 and December 2007 at National Comprehensive Cancer Network centers with survival follow-up through December 2009. Cox proportional hazards regression was used to compare breast cancer–specific survival among Asians (n = 533), Hispanics (n = 1,122), and blacks (n = 1,345) with that among whites (n = 14,268), overall and stratified by subtype (luminal A like, luminal B like, human epidermal growth factor receptor 2 type, and triple negative). Model estimates were used to derive mediation proportion and 95% CI for selected risk factors. Results In multivariable adjusted models, overall, blacks had 21% higher risk of breast cancer–specific death (hazard ratio [HR], 1.21; 95% CI, 1.00 to 1.45). For estrogen receptor–positive tumors, black and white survival differences were greatest within 2 years of diagnosis (years 0 to 2: HR, 2.65; 95% CI, 1.34 to 5.24; year 2 to end of follow-up: HR, 1.50; 95% CI, 1.12 to 2.00). Blacks were 76% and 56% more likely to die as a result of luminal A–like and luminal B–like tumors, respectively. No disparities were observed for triple-negative or human epidermal growth factor receptor 2–type tumors. Asians and Hispanics were less likely to die as a result of breast cancer compared with whites (Asians: HR, 0.56; 95% CI, 0.37 to 0.85; Hispanics: HR, 0.74; 95% CI, 0.58 to 0.95). For blacks, tumor characteristics and stage at diagnosis were significant disparity mediators. Body mass index was an important mediator for blacks and Asians. Conclusion Racial disparities in breast cancer survival vary by tumor subtype. Interventions are needed to reduce disparities, particularly in the first 2 years after diagnosis among black women with estrogen receptor–positive tumors. PMID

  17. Racial and Ethnic Differences in Breast Cancer Survival: Mediating Effect of Tumor Characteristics and Sociodemographic and Treatment Factors.

    PubMed

    Warner, Erica T; Tamimi, Rulla M; Hughes, Melissa E; Ottesen, Rebecca A; Wong, Yu-Ning; Edge, Stephen B; Theriault, Richard L; Blayney, Douglas W; Niland, Joyce C; Winer, Eric P; Weeks, Jane C; Partridge, Ann H

    2015-07-10

    To evaluate the relationship between race/ethnicity and breast cancer-specific survival according to subtype and explore mediating factors. Participants were women presenting with stage I to III breast cancer between January 2000 and December 2007 at National Comprehensive Cancer Network centers with survival follow-up through December 2009. Cox proportional hazards regression was used to compare breast cancer-specific survival among Asians (n = 533), Hispanics (n = 1,122), and blacks (n = 1,345) with that among whites (n = 14,268), overall and stratified by subtype (luminal A like, luminal B like, human epidermal growth factor receptor 2 type, and triple negative). Model estimates were used to derive mediation proportion and 95% CI for selected risk factors. In multivariable adjusted models, overall, blacks had 21% higher risk of breast cancer-specific death (hazard ratio [HR], 1.21; 95% CI, 1.00 to 1.45). For estrogen receptor-positive tumors, black and white survival differences were greatest within 2 years of diagnosis (years 0 to 2: HR, 2.65; 95% CI, 1.34 to 5.24; year 2 to end of follow-up: HR, 1.50; 95% CI, 1.12 to 2.00). Blacks were 76% and 56% more likely to die as a result of luminal A-like and luminal B-like tumors, respectively. No disparities were observed for triple-negative or human epidermal growth factor receptor 2-type tumors. Asians and Hispanics were less likely to die as a result of breast cancer compared with whites (Asians: HR, 0.56; 95% CI, 0.37 to 0.85; Hispanics: HR, 0.74; 95% CI, 0.58 to 0.95). For blacks, tumor characteristics and stage at diagnosis were significant disparity mediators. Body mass index was an important mediator for blacks and Asians. Racial disparities in breast cancer survival vary by tumor subtype. Interventions are needed to reduce disparities, particularly in the first 2 years after diagnosis among black women with estrogen receptor-positive tumors. © 2015 by American Society of Clinical Oncology.

  18. Oncolytic Virotherapy: Molecular Targets in Tumor-Selective Replication and Carrier Cell-Mediated Delivery of Oncolytic Viruses

    PubMed Central

    Guo, Z. Sheng; Thorne, Stephen H.; Bartlett, David L.

    2010-01-01

    Tremendous advances have been made in developing oncolytic viruses (OVs) in the last few years. By taking advantage of current knowledge in cancer biology and virology, specific OVs have been genetically engineered to target specific molecules or signal transduction pathways in cancer cells in order to achieve efficient and selective replication. The viral infection and amplification eventually induces cancer cells into cell death pathways and elicits host anti-tumor immune responses to further help eliminate cancer cells. Specifically targeted molecules or signaling pathways (such as RB/E2F/p16, p53, IFN, PKR, EGFR, Ras, Wnt, anti-apoptosis or hypoxia) in cancer cells or tumor microenvironment have been studied and dissected with a variety of OVs such as adenovirus, herpes simplex virus, poxvirus, vesicular stomatitis virus, measles virus, Newcastle disease virus, influenza virus and reovirus, setting the molecular basis for further improvements in the near future. Another exciting new area of research has been the harnessing of naturally tumor-homing cells as carrier cells (or cellular vehicles) to deliver OVs to tumors. The trafficking of these tumor-homing cells (stem cells, immune cells and cancer cells), which support proliferation of the viruses, is mediated by specific chemokines and cell adhesion molecules and we are just beginning to understand the roles of these molecules. Finally, we will highlight some avenues deserving further study in order to achieve the ultimate goals of utilizing various OVs for effective cancer treatment. PMID:18328829

  19. Altered RNA editing in 3′ UTR perturbs microRNA-mediated regulation of oncogenes and tumor-suppressors

    PubMed Central

    Zhang, Liye; Yang, Chih-Sheng; Varelas, Xaralabos; Monti, Stefano

    2016-01-01

    RNA editing is a molecular event that alters specific nucleotides in RNA post-transcriptionally. RNA editing has the potential to impact a variety of cellular processes and is implicated in diseases such as cancer. Yet, the precise mechanisms by which RNA editing controls cellular processes are poorly understood. Here, we characterize sequences altered by RNA editing in patient samples from lymphoma, neuroblastoma and head and neck cancers. We show that A-to-I RNA editing sites are highly conserved across samples of the same tissue type and that most editing sites identified in tumors are also detectable in normal tissues. Next, we identify the significant changes in editing levels of known sites between tumor and paired “normal” tissues across 14 cancer types (627 pairs) from The Cancer Genome Atlas project and show that the complexity of RNA editing regulation cannot be captured by the activity of ADAR family genes alone. Our pan-cancer analysis confirms previous results on individual tumor types and suggests that changes of RNA editing levels in coding and 3′UTR regions could be a general mechanism to promote tumor growth. We also propose a model explaining how altered RNA editing levels affect microRNA-mediated post-transcriptional regulation of oncogenes and tumor-suppressors. PMID:26980570

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed

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

    2016-09-13

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

  2. Myristoylation of Src kinase mediates Src-induced and high-fat diet-accelerated prostate tumor progression in mice.

    PubMed

    Kim, Sungjin; Yang, Xiangkun; Li, Qianjin; Wu, Meng; Costyn, Leah; Beharry, Zanna; Bartlett, Michael G; Cai, Houjian

    2017-11-10

    Exogenous fatty acids provide substrates for energy production and biogenesis of the cytoplasmic membrane, but they also enhance cellular signaling during cancer cell proliferation. However, it remains controversial whether dietary fatty acids are correlated with tumor progression. In this study, we demonstrate that increased Src kinase activity is associated with high-fat diet-accelerated progression of prostate tumors and that Src kinases mediate this pathological process. Moreover, in the in vivo prostate regeneration assay, host SCID mice carrying Src(Y529F)-transduced regeneration tissues were fed a low-fat diet or a high-fat diet and treated with vehicle or dasatinib. The high-fat diet not only accelerated Src-induced prostate tumorigenesis in mice but also compromised the inhibitory effect of the anticancer drug dasatinib on Src kinase oncogenic potential in vivo We further show that myristoylation of Src kinase is essential to facilitate Src-induced and high-fat diet-accelerated tumor progression. Mechanistically, metabolism of exogenous myristic acid increased the biosynthesis of myristoyl CoA and myristoylated Src and promoted Src kinase-mediated oncogenic signaling in human cells. Of the fatty acids tested, only exogenous myristic acid contributed to increased intracellular myristoyl CoA levels. Our results suggest that targeting Src kinase myristoylation, which is required for Src kinase association at the cellular membrane, blocks dietary fat-accelerated tumorigenesis in vivo Our findings uncover the molecular basis of how the metabolism of myristic acid stimulates high-fat diet-mediated prostate tumor progression. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  3. Oncolytic virus-mediated tumor radiosensitization in mice through DNA-PKcs-specific shRNA

    PubMed Central

    Kon, Takashi; Zhang, Xiuwu; Huang, Qian; Yang, Zhonghui; Liu, Shanling; Yan, Bin; Li, Fang; Wang, He; Li, Chuan-Yuan

    2012-01-01

    One of the key issues in cancer radiotherapy research is to sensitize tumor cells to the cell killing effects of ionizing radiation while leaving normal tissues intact. One potential approach to achieve this is through tumor-specific targeting of DNA repair genes. In this study, we engineered a replication-deficient adenovirus encoding a mini shRNA gene targeted to the DNA-PKcs gene, which is involved in double strand break DNA repair, and evaluated its anti-tumor efficacy in combination with radiotherapy. Our shRNA-encoding adenovirus showed significant efficacy in down-regulating the levels of the DNA-PKcs protein that was accompanied by increased radiation sensitivity in the human HCT116 colon cancer cells. However, when delivered intratumorally to xenograft human tumors, minimal anti-tumor effects of the virus were seen either alone or in combination with radiation therapy, suggesting an inefficiency of the non-replicative adenovirus in delivering shRNA genes to the tumor mass. When a conditionally replicative adenovirus targeted to telomerase-positive tumor cells was used in conjunction with the DNA-PKcs-targeted shRNA-encoding non-replicative adenovirus, the efficiency of tumor-specific anti-DNA-PKcs shRNA gene expression was enhanced significantly. Most importantly, this enhanced shRNA expression led to significant anti-tumor efficacy of concurrently delivered radiation therapy. Our results suggest our shRNA-based DNA-PKcs- targeting approach in combination with tumor-targeting replicative adenovirus is a promising method to sensitize solid tumors to radiation therapy. PMID:22924158

  4. M2 polarization of macrophages by Oncostatin M in hypoxic tumor microenvironment is mediated by mTORC2 and promotes tumor growth and metastasis.

    PubMed

    Shrivastava, Richa; Asif, Mohammad; Singh, Varsha; Dubey, Parul; Ahmad Malik, Showkat; Lone, Mehraj-U-Din; Tewari, Brij Nath; Baghel, Khemraj Singh; Pal, Subhashis; Nagar, Geet Kumar; Chattopadhyay, Naibedya; Bhadauria, Smrati

    2018-04-03

    Oncostatin M (OSM), an inflammatory cytokine belonging to the interleukin-6 (IL-6) superfamily, plays a vital role in multitude of physiological and pathological processes. Its role in breast tumor progression and metastasis to distant organs is well documented. Recent reports implicate OSM in macrophage M2 polarization, a key pro-tumoral phenomenon. M2 polarization of macrophages is believed to promote tumor progression by potentiating metastasis and angiogenesis. In the current study, we delineated the mechanism underlying OSM induced macrophage M2 polarization. The findings revealed that OSM skews macrophages towards an M2 polarized phenotype via mTOR signaling complex 2 (mTORC2). mTORC2 relays signals through two effector kinases i.e. PKC-α and Akt. Our results indicated that mTORC2 mediated M2 polarization of macrophages is not dependent on PKC-α and is primarily affected via Akt, particularly Akt1. In vivo studies conducted on 4T1/BALB/c mouse orthotropic model of breast cancer further corroborated these observations wherein i.v. reintroduction of mTORC2 abrogated monocytes into orthotropic mouse model resulted in diminished acquisition of M2 specific attributes by tumor associated macrophages. Metastasis to distant organs like lung, liver and bone was reduced as evident by decrease in formation of focal metastatic lesions in mTORC2 abrogated monocytes mice. Our study pinpoints key role of mTORC2-Akt1 axis in OSM induced macrophage polarization and suggests for possible usage of Oncostatin-M blockade and/or selective mTORC2 inhibition as a potential anti-cancer strategy particularly with reference to metastasis of breast cancer to distant organs such as lung, liver and bone. Copyright © 2018 Elsevier Ltd. All rights reserved.

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

    PubMed Central

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

    2015-01-01

    Non-steroidal anti-inflammatory drugs prevent colorectal cancer by inhibiting cyclooxygenase (COX) enzymes that synthesize tumor-promoting prostaglandins. 15-hydroxyprostaglandin dehydrogenase (15-PGDH) is a tumor suppressor that degrades tumor-promoting prostaglandins. Murine knockout of 15-PGDH increases susceptibility to azoxymethane-induced colon tumors. It also renders these mice resistant to celecoxib, a selective inhibitor of inducible COX-2 during colon neoplasia. Similarly, humans with low colonic 15-PGDH are also resistant to colon adenoma prevention with celecoxib. Here, we used aspirin and sulindac, which inhibit both COX-1 and COX-2, in order to determine if these broader COX inhibitors can prevent colon tumors in 15-PGDH knockout (KO) mice. Unlike celecoxib, sulindac proved highly effective in colon tumor prevention of 15-PGDH KO mice. Significantly, however, aspirin demonstrated no effect on colon tumor incidence in either 15-PGDH wild-type or KO mice, despite a comparable reduction in colonic mucosal Prostaglandin E2 (PGE2) levels by both sulindac and aspirin. Notably, colon tumor prevention activity by sulindac was accompanied by a marked induction of lymphoid aggregates and proximal colonic inflammatory mass lesions, a side effect seen to a lesser degree with celecoxib, but not with aspirin. These findings suggest that sulindac may be the most effective agent for colon cancer prevention in humans with low 15-PGDH, but its use may also be associated with inflammatory lesions in the colon. PMID:25503930

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

    SciTech Connect

    Chen, S.; Wong, S.; Zhao, X.

    2010-05-01

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

  7. Resistance to EGF receptor inhibitors in glioblastoma mediated by phosphorylation of the PTEN tumor suppressor at tyrosine 240.

    PubMed

    Fenton, Tim R; Nathanson, David; Ponte de Albuquerque, Claudio; Kuga, Daisuke; Iwanami, Akio; Dang, Julie; Yang, Huijun; Tanaka, Kazuhiro; Oba-Shinjo, Sueli Mieko; Uno, Miyuki; Inda, Maria del Mar; Wykosky, Jill; Bachoo, Robert M; James, C David; DePinho, Ronald A; Vandenberg, Scott R; Zhou, Huilin; Marie, Suely K N; Mischel, Paul S; Cavenee, Webster K; Furnari, Frank B

    2012-08-28

    Glioblastoma multiforme (GBM) is the most aggressive of the astrocytic malignancies and the most common intracranial tumor in adults. Although the epidermal growth factor receptor (EGFR) is overexpressed and/or mutated in at least 50% of GBM cases and is required for tumor maintenance in animal models, EGFR inhibitors have thus far failed to deliver significant responses in GBM patients. One inherent resistance mechanism in GBM is the coactivation of multiple receptor tyrosine kinases, which generates redundancy in activation of phosphoinositide-3'-kinase (PI3K) signaling. Here we demonstrate that the phosphatase and tensin homolog deleted on chromosome 10 (PTEN) tumor suppressor is frequently phosphorylated at a conserved tyrosine residue, Y240, in GBM clinical samples. Phosphorylation of Y240 is associated with shortened overall survival and resistance to EGFR inhibitor therapy in GBM patients and plays an active role in mediating resistance to EGFR inhibition in vitro. Y240 phosphorylation can be mediated by both fibroblast growth factor receptors and SRC family kinases (SFKs) but does not affect the ability of PTEN to antagonize PI3K signaling. These findings show that, in addition to genetic loss and mutation of PTEN, its modulation by tyrosine phosphorylation has important implications for the development and treatment of GBM.

  8. Second mitochondria-derived activator of caspase (SMAC) mimetic potentiates tumor susceptibility toward natural killer cell-mediated killing.

    PubMed

    Brinkmann, Kerstin; Hombach, Andreas; Seeger, Jens Michael; Wagner-Stippich, Diana; Klubertz, Daniela; Krönke, Martin; Abken, Hinrich; Kashkar, Hamid

    2014-03-01

    Resistance to apoptosis is a hallmark of cancer, and represents an important mechanism of how tumor cells resist immune cell destruction. Mitochondria are the central regulators of the apoptotic machinery by releasing pro-apoptotic factors including cytochrome c and second mitochondria-derived activator of caspase (SMAC) upon mitochondrial outer membrane permeabilization (MOMP). Small molecules activating MOMP such as BH3 mimetics or antagonizers of the inhibitor of apoptosis proteins (IAPs) such as SMAC mimetics have recently engendered new optimism for a more individualized and effective cancer therapy. Here we show that a SMAC mimetic potentiates cancer cell killing by natural killer (NK) cells through reactivation of tumor cell apoptosis. Specifically, the SMAC mimetic enhances the susceptibility of tumor cells toward NK cell-mediated effector mechanisms involving death receptors and cytolytic granules containing perforin and granzymes by relieving caspase activity. Our data highlight for the first time the specific use of SMAC mimetics for boosting immune cell-mediated immunotherapy, representing a novel and promising approach in the treatment of cancer.

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

    PubMed Central

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

    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-based gene therapeutic approach for GBM using adenoviral (Ads) mediated gene delivery of Herpes Simplex Virus Type 1-thymidine kinase (TK) into the tumor mass to induce tumor cells' death combined with an adenovirus expressing fms-like tyrosine kinase 3 ligand (Flt3L) to recruit dendritic cells (DCs) into the tumor microenvironment. This leads to the induction of specific anti-brain tumor immunity and immunological memory. In a model of GBM recurrence, we demonstrate that Flt3L/TK mediated immunological memory is capable of recognizing brain tumor neoantigens absent from the original treated tumor. These data demonstrate that the Flt3L/TK gene therapeutic approach can induce systemic immunological memory capable of recognizing a brain tumor neoantigen in a model of recurrent GBM. PMID:21505426

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

    PubMed

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

    2017-01-20

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

  11. The Mediating Role of Visuospatial Planning Skills on Adaptive Function Among Young-Adult Survivors of Childhood Brain Tumor.

    PubMed

    King, Tricia Z; Smith, Kristen M; Ivanisevic, Mirjana

    2015-08-01

    The Boston Qualitative Scoring System (BQSS) was used as a method to examine executive skills on the Rey-Osterrieth complex figure (ROCF). Young-adult survivors of childhood brain tumor (N = 31) and a demographically-matched comparison group (N = 33) completed the ROCF copy version and Grooved Pegboard, and informants were administered the Scales of Independent Behavior-Revised (SIB-R) and Behavior Rating Inventory of Executive Function (BRIEF). Survivors had significantly lower BQSS planning and SIB-R community living skills and greater perseveration. Mediation analyses found that BQSS planning skills mediate the relationship between group and community living skills. Convergent findings of the BRIEF Planning, and discriminant findings with the BQSS Fragmentation, BRIEF Emotional Control, and Grooved Pegboard support the planning construct as the specific mediator in this model. Together, these findings highlight the role of planning skills in adaptive functions of young-adult survivors of childhood brain tumor. Published by Oxford University Press 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  12. Effects of MDM2 inhibitors on vascular endothelial growth factor-mediated tumor angiogenesis in human breast cancer.

    PubMed

    Xiong, Jing; Yang, Qin; Li, Jiansha; Zhou, Sheng

    2014-01-01

    Mouse double minute 2 (MDM2) is overexpressed in many malignant tumors, and MDM2 levels are associated with poor prognosis of several human cancers, including breast cancer. In the present study, we investigated the function of MDM2 in vascular endothelial growth factor (VEGF)-mediated tumor angiogenesis of breast cancer and the potential value of MDM2 as an anti-angiogenic therapy target for cancer therapy by inhibiting MDM2 with antisense oligonucleotides (ASO) or other antagonist nutlin-3. Anti-MDM2 ASO and nutlin-3 were evaluated for their in vitro and in vivo anti-angiogenesis activities in different human breast cancer models with a different p53 status: MCF-7 cell line containing wild-type p53 and MDA-MB-468 cell line containing mutant p53. MCF-7 and MDA-MB-468 cells were incubated with different concentrations of ASO or nutlin-3 for various periods of time. VEGF gene and protein expression in tumor cells was measured by qPCR and Western blot. The level of VEGF protein secreted in the culture supernatant of treated cells was quantified by enzyme-linked immunosorbent assay (ELISA). Nude mouse xenograft models were further established to determine their effects on tumor growth and angiogenesis. Serum levels of VEGF were measured by ELISA. VEGF expression and microvessel density in tumor tissues were studied by immunohistochemistry. Both angiogenesis and tumor growth were digitally quantified. In both MCF-7 and MDA-MB-468 cells, VEGF expression and secretion were reduced, resulting from specific inhibition of MDM2 expression by ASO. In vivo assay, after administration of ASO, VEGF production reduced and anti-angiogenesis activity occurred in nude mice bearing MCF-7 or MDA-MB-468 xenograft. However, in both models treated with nutlin-3, VEGF production was not changed and anti-angiogenesis activity was not observed. In summary, the ASO construct targeting MDM2 specifically suppresses VEGF expression in vitro and VEGF-mediated tumor angiogenesis in vivo in breast

  13. Adenosine A2Areceptor involves in neuroinflammation-mediated cognitive decline through activating microglia under acute hypobaric hypoxia.

    PubMed

    Chen, Peng-Zhi; He, Wen-Juan; Zhu, Zhi-Ru; E, Guo-Ji; Xu, Gang; Chen, De-Wei; Gao, Yu-Qi

    2018-03-06

    Hypobaric hypoxia (HH) at high altitudes leads to a wide range of cognitive impairments which can handicap human normal activities and performances. However, the underlying mechanism is still unclear. Adenosine A 2A receptors (A 2A Rs) of the brain are pivotal to synaptic plasticity and cognition. Besides, insult-induced up-regulation of A 2A R regulates neuroinflammation and therefore induces brain damages in various neuropathological processes. The present study was designed to determine whether A 2A R-mediate neuroinflammation involves in cognitive impairments under acute HH. A 2A R knock-out and wild-type male mice were exposed to a simulated altitude of 8000 m for 7 consecutive days in a hypobaric chamber and simultaneously received behavioral tests including Morris water maze test and open filed test. A 2A R expression, the activation of microglia and the production of TNF-α were evaluated in the hippocampus by immunohistochemistry and ELISA, respectively. Behavioral tests showed that acute HH exposure caused the dysfunction of spatial memory and mood, while genetic inactivation of A 2A R attenuated the impairment of spatial memory but not that of mood. Double-labeled immunofluorescence showed that A 2A Rs were mainly expressed on microglia and up-regulated in the hippocampus of acute HH model mice. Acute HH also induced the accumulation of microglia and increased production of TNF-α in the hippocampus, which could be markedly inhibited by A 2A R inactivation. These findings indicate that microglia-mediated neuroinflammation triggered by A 2A R activation involves in acute HH-induced spatial memory impairment and that A 2A R could be a new target for the pharmacotherapy of cognitive dysfunction at high altitudes. Copyright © 2018. Published by Elsevier B.V.

  14. Tumor Angiogenesis: MMP-Mediated Induction of Intravasation- and Metastasis-Sustaining Neovasculature

    PubMed Central

    Deryugina, Elena I.; Quigley, James P.

    2016-01-01

    Metastasis is a distinct stage of cancer progression that requires the development of angiogenic blood vessels serving as conduits for tumor cell dissemination. An accumulated body of evidence indicates that metastasis-supporting neovasculature should possess certain structural characteristics allowing for the process of tumor cell intravasation, an active entry of cancer cells into the vessel interior. It appears that the development of tumor vessels with lumens of a distinctive size and their structure supported by a discontinuous pericyte coverage, together constitute critical microarchitectural requirements to: (a) provide accessible points for vessel wall penetration by primary tumor cells; (b) provide enough lumen space for a tumor cell or cell aggregate upon intravasation; and (c) allow for sufficient rate of blood flow to carry away intravasated cells from the primary tumor to the next, proximal or distal site. This review will primarily focus on the functional roles of matrix metalloproteinases (MMPs), which catalytically trigger the development of an intravasation-sustaining neovasculature at the early stages of tumor growth and are also required for the maintenance of a metastasis-supporting state of blood vessels at later stages of cancer progression. PMID:25912949

  15. Modeling stromal determinants of 3D tumor growth to inform PDT-mediated combination treatments

    NASA Astrophysics Data System (ADS)

    Rizvi, I.; Anbil, S.; Celli, J. P.; Alagic, N.; Massodi, I.; Hasan, T.

    2013-03-01

    Advanced stage ovarian carcinoma is characterized by poor prognosis and peritoneal micronodules that exhibit treatment resistance. This is partially due to interactions between multifocal disease and the tumor microenvironment, which includes tumor endothelial cells (TECs) and extracellular matrix components (ECM). Here we describe the development of a three-dimensional model of ovarian cancer that incorporates TECs and ECM. A comparison of several methodologies to generate endothelialized ovarian micronodules along with a preliminary physical characterization is described. This model will allow for detailed investigation of tumor-stroma interactions and how they impact disease progression and treatment response.

  16. HLA-mediated tumor escape mechanisms that may impair immunotherapy clinical outcomes via T-cell activation.

    PubMed

    Rodríguez, Josefa A

    2017-10-01

    Although the immune system provides protection from cancer by means of immunosurveillance, which serves a major function in eliminating cancer cells, it may also lead to cancer immunoediting, molding tumor immunogenicity. Cancer cells exploit several molecular mechanisms to thwart immune-mediated death by disabling cellular components of the immune system associated with tumor recognition and rejection. Human leukocyte antigen (HLA) molecules are mandatory for the immune recognition and subsequent killing of neoplastic cells by the immune system, as tumor antigens must be presented in an HLA-restricted manner to be recognized by T-cell receptors. Impaired HLA-I expression prevents the activation of cytotoxic immune mechanisms, whereas impaired HLA-II expression affects the antigen-presenting capability of antigen presenting cells. Aberrant HLA-G expression by cancer cells favors immune escape by inhibiting the activities of virtually all immune cells. The development of cancer therapies based on T-cell activation must consider these HLA-associated immune evasion mechanisms, as alterations in their expression occur early and frequently in the majority of types of cancer, and have an adverse impact on the clinical response to immunotherapy. Herein, the concept of altered HLA expression as a mechanism exploited by tumors to escape immune control and induce an immunosuppressive environment is reviewed. A number of novel clinical immunotherapeutic approaches used for cancer treatment are also reviewed, and strategies for overcoming the limitations of these immunotherapeutic interventions are proposed.

  17. Populational equilibrium through exosome-mediated Wnt signaling in tumor progression of diffuse large B-cell lymphoma.

    PubMed

    Koch, Raphael; Demant, Martin; Aung, Thiha; Diering, Nina; Cicholas, Anna; Chapuy, Bjoern; Wenzel, Dirk; Lahmann, Marlen; Güntsch, Annemarie; Kiecke, Christina; Becker, Sabrina; Hupfeld, Timo; Venkataramani, Vivek; Ziepert, Marita; Opitz, Lennart; Klapper, Wolfram; Trümper, Lorenz; Wulf, Gerald G

    2014-04-03

    Tumors are composed of phenotypically heterogeneous cell populations. The nongenomic mechanisms underlying transitions and interactions between cell populations are largely unknown. Here, we show that diffuse large B-cell lymphomas possess a self-organized infrastructure comprising side population (SP) and non-SP cells, where transitions between clonogenic states are modulated by exosome-mediated Wnt signaling. DNA methylation modulated SP-non-SP transitions and was correlated with the reciprocal expressions of Wnt signaling pathway agonist Wnt3a in SP cells and the antagonist secreted frizzled-related protein 4 in non-SP cells. Lymphoma SP cells exhibited autonomous clonogenicity and exported Wnt3a via exosomes to neighboring cells, thus modulating population equilibrium in the tumor.

  18. Folic acid-mediated targeting of cowpea mosaic virus particles to tumor cells

    PubMed Central

    Destito, Giuseppe; Yeh, Robert; Rae, Chris S.; Finn, M. G.; Manchester, Marianne

    2007-01-01

    Summary Cowpea mosaic virus (CPMV) is a well-characterized nanoparticle that has been used for a variety of nanobiotechnology applications. CPMV interacts with several mammalian cell lines and tissues in vivo. To overcome natural CPMV targeting and re-direct CPMV particles to cells of interest, we attached a novel folic acid-PEG conjugate using the copper-catalyzed azide-alkyne cycloaddition reaction. PEGylation of CPMV completely eliminated background binding of the virus to tumor cells. The PEG-folate moiety allowed CPMV specific recognition of tumor cells bearing the folate receptor. In addition, by testing CPMV formulations with different amounts of the PEG-FA moiety displayed on the surface, we show that higher-density loading of targeting ligands on CPMV may not be necessary for efficient targeting to tumor cells. These studies help to define the requirements for efficiently targeting nanoparticles and protein cages to tumors. PMID:17961827

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

    PubMed

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

    2015-02-01

    Non-steroidal anti-inflammatory drugs prevent colorectal cancer by inhibiting cyclooxygenase (COX) enzymes that synthesize tumor-promoting prostaglandins. 15-hydroxyprostaglandin dehydrogenase (15-PGDH) is a tumor suppressor that degrades tumor-promoting prostaglandins. Murine knockout of 15-PGDH increases susceptibility to azoxymethane-induced colon tumors. It also renders these mice resistant to celecoxib, a selective inhibitor of inducible COX-2 during colon neoplasia. Similarly, humans with low colonic 15-PGDH are also resistant to colon adenoma prevention with celecoxib. Here, we used aspirin and sulindac, which inhibit both COX-1 and COX-2, in order to determine if these broader COX inhibitors can prevent colon tumors in 15-PGDH knockout (KO) mice. Unlike celecoxib, sulindac proved highly effective in colon tumor prevention of 15-PGDH KO mice. Significantly, however, aspirin demonstrated no effect on colon tumor incidence in either 15-PGDH wild-type or KO mice, despite a comparable reduction in colonic mucosal Prostaglandin E₂ (PGE₂) levels by both sulindac and aspirin. Notably, colon tumor prevention activity by sulindac was accompanied by a marked induction of lymphoid aggregates and proximal colonic inflammatory mass lesions, a side effect seen to a lesser degree with celecoxib, but not with aspirin. These findings suggest that sulindac may be the most effective agent for colon cancer prevention in humans with low 15-PGDH, but its use may also be associated with inflammatory lesions in the colon. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  20. Indolyl-quinuclidinols inhibit ENOX activity and endothelial cell morphogenesis while enhancing radiation-mediated control of tumor vasculature

    PubMed Central

    Geng, Ling; Rachakonda, Girish; Morré, D. James; Morré, Dorothy M.; Crooks, Peter A.; Sonar, Vijayakumar N.; Roti, Joseph L. Roti; Rogers, Buck E.; Greco, Suellen; Ye, Fei; Salleng, Kenneth J.; Sasi, Soumya; Freeman, Michael L.; Sekhar, Konjeti R.

    2009-01-01

    There is a need for novel strategies that target tumor vasculature, specifically those that synergize with cytotoxic therapy, in order to overcome resistance that can develop with current therapeutics. A chemistry-driven drug discovery screen was employed to identify novel compounds that inhibit endothelial cell tubule formation. Cell-based phenotypic screening revealed that noncytotoxic concentrations of (Z)-(±)-2-(1-benzenesulfonylindol-3-ylmethylene)-1-azabicyclo[2. 2.2]octan-3-ol (analog I) and (Z)-(±)-2-(1-benzylindol-3-ylmethylene)-1-azabicyclo[2.2.2]octan-3-ol (analog II) inhibited endothelial cell migration and the ability to form capillary-like structures in Matrigel by ≥70%. The ability to undergo neoangiogenesis, as measured in a window-chamber model, was also inhibited by 70%. Screening of biochemical pathways revealed that analog II inhibited the enzyme ENOX1 (EC50 = 10 μM). Retroviral-mediated shRNA suppression of endothelial ENOX1 expression inhibited cell migration and tubule formation, recapitulating the effects observed with the small-molecule analogs. Genetic or chemical suppression of ENOX1 significantly increased radiation-mediated Caspase3-activated apoptosis, coincident with suppression of p70S6K1 phosphorylation. Administration of analog II prior to fractionated X-irradiation significantly diminished the number and density of tumor microvessels, as well as delayed syngeneic and xenograft tumor growth compared to results obtained with radiation alone. Analysis of necropsies suggests that the analog was well tolerated. These results suggest that targeting ENOX1 activity represents a novel therapeutic strategy for enhancing the radiation response of tumors.—Geng, L., Rachakonda, G., Morré, D. J., Morré, D. M., Crooks, P. A., Sonar, V. N., Roti Roti, J. L., Rogers, B. E., Greco, S., Ye, F., Salleng, K. J., Sasi, S., Freeman, M. L., Sekhar, K. R. Indolyl-quinuclidinols inhibit ENOX activity and endothelial cell morphogenesis while

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

    SciTech Connect

    Liu, Ying; Zhou, Mei; Luo, Dan

    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, anaerobicmore » 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.« less

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

    PubMed

    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

  3. Annexin A2 Mediates Mycoplasma pneumoniae Community-Acquired Respiratory Distress Syndrome Toxin Binding to Eukaryotic Cells

    PubMed Central

    Somarajan, Sudha R.; Al-Asadi, Fadi; Ramasamy, Kumaraguruparan; Pandranki, Lavanya

    2014-01-01

    ABSTRACT Mycoplasma pneumoniae synthesizes a novel human surfactant protein A (SP-A)-binding cytotoxin, designated community-acquired respiratory distress syndrome (CARDS) toxin, that exhibits ADP-ribosylating and vacuolating activities in mammalian cells and is directly linked to a range of acute and chronic airway diseases, including asthma. In our attempt to detect additional CARDS toxin-binding proteins, we subjected the membrane fraction of human A549 airway cells to affinity chromatography using recombinant CARDS toxin as bait. A 36-kDa A549 cell membrane protein bound to CARDS toxin and was identified by time of flight (TOF) mass spectroscopy as annexin A2 (AnxA2) and verified by immunoblotting with anti-AnxA2 monoclonal antibody. Dose-dependent binding of CARDS toxin to recombinant AnxA2 reinforced the specificity of the interaction, and further studies revealed that the carboxy terminus of CARDS toxin mediated binding to AnxA2. In addition, pretreatment of viable A549 cells with anti-AnxA2 monoclonal antibody or AnxA2 small interfering RNA (siRNA) reduced toxin binding and internalization. Immunofluorescence analysis of CARDS toxin-treated A549 cells demonstrated the colocalization of CARDS toxin with cell surface-associated AnxA2 upon initial binding and with intracellular AnxA2 following toxin internalization. HepG2 cells, which express low levels of AnxA2, were transfected with a plasmid expressing AnxA2 protein, resulting in enhanced binding of CARDS toxin and increased vacuolization. In addition, NCI-H441 cells, which express both AnxA2 and SP-A, upon AnxA2 siRNA transfection, showed decreased binding and subsequent vacuolization. These results indicate that CARDS toxin recognizes AnxA2 as a functional receptor, leading to CARDS toxin-induced changes in mammalian cells. PMID:25139904

  4. Adenosine receptor A2b on hematopoietic cells mediates LPS-induced migration of PMNs into the lung interstitium.

    PubMed

    Konrad, Franziska M; Witte, Esther; Vollmer, Irene; Stark, Stefanie; Reutershan, Jörg

    2012-09-01

    Uncontrolled transmigration of polymorphonuclear leukocytes (PMNs) into the different compartments of the lungs (intravascular, interstitial, alveolar) is a critical event in the early stage of acute lung injury and acute respiratory distress syndrome. Adenosine receptor A(2b) is highly expressed in the inflamed lungs and has been suggested to mediate cell trafficking. In a murine model of LPS-induced lung inflammation, we investigated the role of A(2b) on migration of PMNs into the different compartments of the lung. In A(2b)(-/-) mice, LPS-induced accumulation of PMNs was significantly higher in the interstitium, but not in the alveolar space. In addition, pulmonary clearance of PMNs was delayed in A(2b)(-/-) mice. Using chimeric mice, we identified A(2b) on hematopoietic cells as crucial for PMN migration. A(2b) did not affect the release of relevant chemokines into the alveolar space. LPS-induced microvascular permeability was under the control of A(2b) on both hematopoietic and nonhematopoietic cells. Activation of A(2b) on endothelial cells also reduced formation of LPS-induced stress fibers, highlighting its role for endothelial integrity. A specific A(2b) agonist (BAY 60-6583) was effective in decreasing PMN migration into the lung interstitium and microvascular permeability. In addition, in vitro transmigration of human PMNs through a layer of human endothelial or epithelial cells was A(2b) dependent. Activation of A(2b) on human PMNs reduced oxidative burst activity. Together, our results demonstrate anti-inflammatory effects of A(2b) on two major characteristics of acute lung injury, with a distinct role of hematopoietic A(2b) for cell trafficking and endothelial A(2b) for microvascular permeability.

  5. Singlet oxygen explicit dosimetry to predict long-term local tumor control for Photofrin-mediated photodynamic therapy

    NASA Astrophysics Data System (ADS)

    Penjweini, Rozhin; Kim, Michele M.; Ong, Yi Hong; Zhu, Timothy C.

    2017-02-01

    Although photodynamic therapy (PDT) is an established modality for the treatment of cancer, current dosimetric quantities do not account for the variations in PDT oxygen consumption for different fluence rates (φ). In this study we examine the efficacy of reacted singlet oxygen concentration ([1O2]rx) to predict long-term local control rate (LCR) for Photofrin-mediated PDT. Radiation-induced fibrosarcoma (RIF) tumors in the right shoulders of female C3H mice are treated with different in-air fluences of 225-540 J/cm2 and in-air fluence rate (φair) of 50 and 75 mW/cm2 at 5 mg/kg Photofrin and a drug-light interval of 24 hours using a 1 cm diameter collimated laser beam at 630 nm wavelength. [1O2]rx is calculated by using a macroscopic model based on explicit dosimetry of Photofrin concentration, tissue optical properties, tissue oxygenation and blood flow changes during PDT. The tumor volume of each mouse is tracked for 90 days after PDT and Kaplan-Meier analyses for LCR are performed based on a tumor volume <=100 mm3, for the four dose metrics light fluence, photosensitizer photobleaching rate, PDT dose and [1O2]rx. PDT dose is defined as a temporal integral of photosensitizer concentration and Φ at a 3 mm tumor depth. φ is calculated throughout the treatment volume based on Monte-Carlo simulation and measured tissue optical properties. Our preliminary studies show that [1O2]rx is the best dosimetric quantity that can predict tumor response and correlate with LCR. Moreover, [1O2]rx calculated using the blood flow changes was in agreement with [1O2]rx calculated based on the actual tissue oxygenation.

  6. Near-infrared mediated tumor destruction by photothermal effect of PANI-Np in vivo

    NASA Astrophysics Data System (ADS)

    Ibarra, L. E.; Yslas, E. I.; Molina, M. A.; Rivarola, C. R.; Romanini, S.; Barbero, C. A.; Rivarola, V. A.; Bertuzzi, M. L.

    2013-06-01

    Photothermal therapy is a therapy in which photon energy is converted into heat to kill cancer. The purpose of this study is to evaluate the in vivo efficacy of photothermal therapy, toxicity and hepatic and renal function of polyaniline nanoparticles (PANI-Np) in a tumor-bearing mice model. The in vivo efficacy of nanoparticles, following NIR light exposure, was assessed by examining tumor growth over time compared to the untreated control. Signs of drug toxicity and the histopathology and morphology of tumor and tissues, after intratumoral injection treatment, were examined or monitored. Excellent photothermal therapy efficacy is achieved upon intratumoral injection of PANI-Np followed by near-infrared light exposure. These results suggest that PANI-Np could be considered as an effective photothermal agent and pave the way to future cancer therapeutics.

  7. Mechanisms involved in hemoglobin-mediated oxidation of lipids in washed fish muscle and inhibitory effects of phospholipase A2.

    PubMed

    Tatiyaborworntham, Nantawat; Richards, Mark P

    2017-11-13

    Hemoglobin (Hb) is a lipid oxidation promoter in fish muscle. Phospholipase A2 (PLA2; EC 3.1.1.4) is linked to an increased resistance to lipid oxidation of frozen-thawed cod fillets via an unknown mechanism. The present study aimed to investigate the mechanism of Hb-mediated lipid oxidation with a focus on ferryl Hb and methemoglobin (metHb), the pro-oxidative Hb species, and to examine how porcine pancreatic PLA2 inhibits Hb-mediated lipid oxidation in washed cod muscle (WCM). Lipid hydroperoxides (LOOHs) and thiobarbituric acid reactive substances (TBARS) were measured as primary and secondary lipid oxidation products, respectively. The formation of metHb and ferryl Hb was also monitored. Ferryl Hb and metHb formed during the Hb-mediated lipid oxidation. PLA2 inhibited the formation of LOOHs and TBARS and suppressed the formation of metHb and ferryl Hb. WCM was pre-oxidized by hemin to increase the amount of LOOHs. PLA2 promoted the depletion of LOOHs in the pre-oxidized WCM with limited TBARS formation at the expense of the heme moiety of Hb. The results of the present study suggest that ferryl Hb may play a role in Hb-mediated lipid oxidation and that PLA2 from pig pancreas may work together with Hb as a novel antioxidant with an ability to remove pre-formed LOOHs from a lipid substrate. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  8. Angiogenesis-targeting microbubbles combined with ultrasound-mediated gene therapy in brain tumors.

    PubMed

    Chang, En-Ling; Ting, Chien-Yu; Hsu, Po-Hong; Lin, Yu-Chun; Liao, En-Chi; Huang, Chiung-Yin; Chang, Yuan-Chih; Chan, Hong-Lin; Chiang, Chi-Shiun; Liu, Hao-Li; Wei, Kuo-Chen; Fan, Ching-Hsiang; Yeh, Chih-Kuang

    2017-06-10

    The major challenges in gene therapy for brain cancer are poor transgene expression due to the blood-brain barrier (BBB) and neurologic damage caused by conventional intracerebral injection. Non-viral gene delivery using ultrasound-targeted microbubbles (MBs) oscillation via the systematic transvascular route is attractive, but there is currently no high-yielding and targeted gene expression method. In this study, we developed a non-viral and angiogenesis-targeting gene delivery approach for efficient brain tumor gene therapy without brain damage. We developed a VEGFR2-targeted and cationic microbubbles (VCMBs) gene vector for use with transcranial focused ultrasound (FUS) exposure to allow transient gene delivery. The system was tested in a brain tumor model using the firefly luciferase gene and herpes simplex virus type 1 thymidine kinase/ganciclovir (pHSV-TK/GCV) with VCMBs under FUS exposure for transgene expression and anti-tumor effect. In vitro data showed that VCMBs have a high DNA-loading efficiency and high affinity for cancer cells. In vivo data confirmed that this technique enhanced gene delivery into tumor tissues without affecting normal brain tissues. The VCMBs group resulted in higher luciferase expression (3.8 fold) relative to the CMBs group (1.9 fold), and the direct injection group. The tumor volume on day 25 was significantly smaller in rats treated with the pHSV-TK/GCV system using VCMBs under FUS (9.7±5.2mm 3 ) than in the direct injection group (40.1±4.3mm 3 ). We demonstrated the successful use of DNA-loaded VCMBs and FUS for non-viral, non-invasive and targeted gene delivery to brain tumors. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Enhancing cancer immunotherapy through nanotechnology-mediated tumor infiltration and activation of immune cells.

    PubMed

    Shen, Haifa; Sun, Tong; Hoang, Hanh H; Burchfield, Jana S; Hamilton, Gillian F; Mittendorf, Elizabeth A; Ferrari, Mauro

    2017-12-01

    Cancer immunotherapy has become arguably the most promising advancement in cancer research and therapy in recent years. The efficacy of cancer immunotherapy is critically dependent on specific physiological and physical processes - collectively referred to as transport barriers - including the activation of T cells by antigen presenting cells, T cells migration to and penetration into the tumor microenvironment, and movement of nutrients and other immune cells through the tumor microenvironment. Nanotechnology-based approaches have great potential to help overcome these transport barriers. In this review, we discuss the ways that nanotechnology is being leveraged to improve the efficacy and potency of various cancer immunotherapies. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

    NASA Astrophysics Data System (ADS)

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

    2007-02-01

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

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

    PubMed

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

    2017-02-01

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

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

    PubMed

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

    2014-01-01

    Immune suppression is well documented during tumor progression, which includes loss of effect of T cells and expansion of T regulatory (Treg) cells. IL-7 plays a key role in the proliferation, survival and homeostasis of T cells and displays a potent antitumor activity in vivo. In the present study, we investigated the antitumor effect of IL-7 in Meth A model. IL-7 inhibited tumor growth and prolonged the survival of tumor-bearing mice with corresponding increases in the frequency of CD4 and CD8 T cells, Th1 (CD4(+)IFN-γ(+)), Tc1 (CD8(+)IFN-γ(+)) and T cells cytolytic activity against Meth A cells. Neutralization of CD4 or CD8 T cells reversed the antitumor benefit of IL-7. Furthermore, IL-7 decreased regulatory T Foxp3 as well as cells suppressive activity with a reciprocal increase in SMAD7. In addition, we observed an increase of the serum concentrations of IL-6 and IFN-γ, and a significant decrease of TGF-β and IL-10 after IL-7 treatment. Taken together, these results indicate that IL-7 augments T cell-mediated antitumor immunity and improves the effect of antitumor in Meth A model. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Dormant tumor cells expressing LOXL2 acquire a stem-like phenotype mediating their transition to proliferative growth.

    PubMed

    Weidenfeld, Keren; Schif-Zuck, Sagi; Abu-Tayeh, Hanan; Kang, Keunsoo; Kessler, Ofra; Weissmann, Marina; Neufeld, Gera; Barkan, Dalit

    2016-11-01

    Recurrence of breast cancer disease years after treatment appears to arise from disseminated dormant tumor cells (DTC). The mechanisms underlying the outgrowth of DTC remain largely unknown. Here we demonstrate that dormant MCF-7 cells expressing LOXL2 acquire a cancer stem cell (CSC)-like phenotype, mediating their outgrowth in the 3D BME system that models tumor dormancy and outgrowth. Similarly, MCF-7-LOXL2 cells colonizing the lung transitioned from dormancy to metastatic outgrowth whereas MCF-7 cells remained dormant. Notably, epithelial to mesenchymal transition (EMT) of MCF-7-LOXL2 cells was required for their CSC-like properties and their transition to metastatic outgrowth. These findings were further supported by clinical data demonstrating that increase in LOXL2 mRNA levels correlates with increase in the mRNA levels of EMT and stem cells markers, and is also associated with decrease in relapse free survival of breast cancer patients. Notably, conditional hypoxia induced expression of endogenous LOXL2 in MCF-7 cells promoted EMT and the acquisition of a CSC-like phenotype, while knockdown of LOXL2 inhibited this transition. Overall, our results demonstrate that expression of LOXL2 endowed DTC with CSC-like phenotype driving their transition to metastatic outgrowth and this stem-like phenotype is dependent on EMT that can be driven by the tumor microenvironment.

  14. EGFR-Targeted Granzyme B Expressed in NK Cells Enhances Natural Cytotoxicity and Mediates Specific Killing of Tumor Cells

    PubMed Central

    Oberoi, Pranav; Jabulowsky, Robert A.; Bähr-Mahmud, Hayat; Wels, Winfried S.

    2013-01-01

    Natural killer (NK) cells are highly specialized effectors of the innate immune system that hold promise for adoptive cancer immunotherapy. Their cell killing activity is primarily mediated by the pro-apoptotic serine protease granzyme B (GrB), which enters targets cells with the help of the pore-forming protein perforin. We investigated expression of a chimeric GrB fusion protein in NK cells as a means to augment their antitumoral activity. For selective targeting to tumor cells, we fused the epidermal growth factor receptor (EGFR) peptide ligand transforming growth factor α (TGFα) to human pre-pro-GrB. Established human NKL natural killer cells transduced with a lentiviral vector expressed this GrB-TGFα (GrB-T) molecule in amounts comparable to endogenous wildtype GrB. Activation of the genetically modified NK cells by cognate target cells resulted in the release of GrB-T together with endogenous granzymes and perforin, which augmented the effector cells' natural cytotoxicity against NK-sensitive tumor cells. Likewise, GrB-T was released into the extracellular space upon induction of degranulation with PMA and ionomycin. Secreted GrB-T fusion protein displayed specific binding to EGFR-overexpressing tumor cells, enzymatic activity, and selective target cell killing in the presence of an endosomolytic activity. Our data demonstrate that ectopic expression of a targeted GrB fusion protein in NK cells is feasible and can enhance antitumoral activity of the effector cells. PMID:23573299

  15. Tumor suppressor KAI1 affects integrin {alpha}v{beta}3-mediated ovarian cancer cell adhesion, motility, and proliferation

    SciTech Connect

    Ruseva, Zlatna; Geiger, Pamina Xenia Charlotte; Hutzler, Peter

    2009-06-10

    The tetraspanin KAI1 had been described as a metastasis suppressor in many different cancer types, a function for which associations of KAI1 with adhesion and signaling receptors of the integrin superfamily likely play a role. In ovarian cancer, integrin {alpha}v{beta}3 correlates with tumor progression and its elevation in vitro provoked enhanced cell adhesion accompanied by significant increases in cell motility and proliferation in the presence of its major ligand vitronectin. In the present study, we characterized integrin {alpha}v{beta}3-mediated tumor biological effects as a function of cellular KAI1 restoration and proved for the first time that KAI1, besides its already knownmore » physical crosstalk with {beta}1-integrins, also colocalizes with integrin {alpha}v{beta}3. Functionally, elevated KAI1 levels drastically increased integrin {alpha}v{beta}3/vitronectin-dependent ovarian cancer cell adhesion. Since an intermediate level of cell adhesive strength is required for optimal cell migration, we next studied ovarian cancer cell motility as a function of KAI1 restoration. By time lapse video microscopy, we found impaired integrin {alpha}v{beta}3/vitronectin-mediated cell migration most probably due to strongly enhanced cellular immobilization onto the adhesion-supporting matrix. Moreover, KAI1 reexpression significantly diminished cell proliferation. These data strongly indicate that KAI1 may suppress ovarian cancer progression by inhibiting integrin {alpha}v{beta}3/vitronectin-provoked tumor cell motility and proliferation as important hallmarks of the oncogenic process.« less

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

    PubMed

    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.

  17. Electric field-mediated transport of plasmid DNA in tumor interstitium in vivo.

    PubMed

    Henshaw, Joshua W; Zaharoff, David A; Mossop, Brian J; Yuan, Fan

    2007-11-01

    Local pulsed electric field application is a method for improving non-viral gene delivery. Mechanisms of the improvement include electroporation and electrophoresis. To understand how electrophoresis affects pDNA delivery in vivo, we quantified the magnitude of electric field-induced interstitial transport of pDNA in 4T1 and B16.F10 tumors implanted in mouse dorsal skin-fold chambers. Four different electric pulse sequences were used in this study, each consisted of 10 identical pulses that were 100 or 400 V/cm in strength and 20 or 50 ms in duration. The interval between consecutive pulses was 1 s. The largest distance of transport was obtained with the 400 V/cm and 50 ms pulse, and was 0.23 and 0.22 microm/pulse in 4T1 and B16.F10 tumors, respectively. There were no significant differences in transport distances between 4T1 and B16.F10 tumors. Results from in vivo mapping and numerical simulations revealed an approximately uniform intratumoral electric field that was predominantly in the direction of the applied field. The data in the study suggested that interstitial transport of pDNA induced by a sequence of ten electric pulses was ineffective for macroscopic delivery of genes in tumors. However, the induced transport was more efficient than passive diffusion.

  18. Targeting MUC1 mediated tumor stromal metabolic interaction in Triple negative Breast Cancer

    DTIC Science & Technology

    2016-11-01

    phosphorylation of MUC1 enhances invasiveness in pancreatic adenocarcinoma cells. Cancer Res, 2007. 67(11): p. 5201-10. 9. Behrens, M.E., et al., The reactive tumor...stabilizes and activates hypoxia-inducible factor 1 alpha to regulate metabolism in pancreatic cancer. Proc Natl Acad Sci U S A, 2012. 109(34): p

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

    DTIC Science & Technology

    2016-11-01

    phosphorylation of MUC1 enhances invasiveness in pancreatic adenocarcinoma cells. Cancer Res, 2007. 67(11): p. 5201-10. 9. Behrens, M.E., et al., The reactive tumor...stabilizes and activates hypoxia-inducible factor 1 alpha to regulate metabolism in pancreatic cancer. Proc Natl Acad Sci U S A, 2012. 109(34): p

  20. NQO1-Mediated Tumor-Selective Lethality and Radiosensitization for Head and Neck Cancer.

    PubMed

    Li, Long-Shan; Reddy, Srilakshmi; Lin, Zhen-Hua; Liu, Shuangping; Park, Hyunsil; Chun, Stephen G; Bornmann, William G; Thibodeaux, Joel; Yan, Jingsheng; Chakrabarti, Gaurab; Xie, Xian-Jin; Sumer, Baran D; Boothman, David A; Yordy, John S

    2016-07-01

    Ionizing radiation (IR) is a key therapeutic regimen for many head and neck cancers (HNC). However, the 5-year overall survival rate for locally advanced HNCs is approximately 50% and better therapeutic efficacy is needed. quinone oxidoreductase 1 (NQO1) is overexpressed in many cancers, and β-lapachone (β-lap), a unique NQO1 bioactivatable drug, exploits this enzyme to release massive reactive oxygen species (ROS) that synergize with IR to kill by programmed necrosis. β-Lap represents a novel therapeutic opportunity in HNC leading to tumor-selective lethality that will enhance the efficacy of IR. Immunohistochemical staining and Western blot assays were used to assess the expression levels of NQO1 in HNC cells and tumors. Forty-five percent of endogenous HNCs expressed elevated NQO1 levels. In addition, multiple HNC cell lines and tumors demonstrated elevated levels of NQO1 expression and activity and were tested for anticancer lethality and radiosensitization by β-lap using long-term survival assays. The combination of nontoxic β-lap doses and IR significantly enhanced NQO1-dependent tumor cell lethality, increased ROS, TUNEL-positive cells, DNA damage, NAD(+), and ATP consumption, and resulted in significant antitumor efficacy and prolonged survival in two xenograft murine HNC models, demonstrating β-lap radiosensitization of HNCs through a NQO1-dependent mechanism. This translational study offers a potential biomarker-driven strategy using NQO1 expression to select tumors susceptible to β-lap-induced radiosensitization. Mol Cancer Ther; 15(7); 1757-67. ©2016 AACR. ©2016 American Association for Cancer Research.

  1. First demonstration of gold nanorods-mediated photodynamic therapeutic destruction of tumors via near infra-red light activation.

    PubMed

    Vankayala, Raviraj; Huang, Yu-Kuan; Kalluru, Poliraju; Chiang, Chi-Shiun; Hwang, Kuo Chu

    2014-04-24

    Previously, a large volume of papers reports that gold nanorods (Au NRs) are able to effectively kill cancer cells upon high laser doses (usually 808 nm, 1-48 W/cm²) irradiation, leading to hyperthermia-induced destruction of cancer cells, i.e, photothermal therapy (PTT) effects. Combination of Au NRs-mediated PTT and organic photosensitizers-mediated photodynamic therapy (PDT) were also reported to achieve synergistic PTT and PDT effects on killing cancer cells. Herein, we demonstrate for the first time that Au NRs alone can sensitize formation of singlet oxygen (¹O₂) and exert dramatic PDT effects on complete destrcution of tumors in mice under very low LED/laser doses of single photon NIR (915 nm, <130 mW/cm²) light excitation. By changing the NIR light excitation wavelengths, Au NRs-mediated phototherapeutic effects can be switched from PDT to PTT or combination of both. Both PDT and PTT effects were confirmed by measurements of reactive oxygen species (ROS) and heat shock protein (HSP 70), singlet oxygen sensor green (SOSG) sensing, and sodium azide quenching in cellular experiments. In vivo mice experiments further show that the PDT effect via irradiation of Au NRs by 915 nm can destruct the B16F0 melanoma tumor in mice far more effectively than doxorubicin (a clinically used anti-cancer drug) as well as the PTT effect (via irradiation of Au NRs by 780 nm light). In addition, we show that Au NRs can emit single photon-induced fluorescence to illustrate their in vivo locations/distribution. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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

    PubMed Central

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

    2017-01-01

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

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

    SciTech Connect

    Kasid, A.; Morecki, S.; Aebersold, P.

    1990-01-01

    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 (Neo{sup R}) using the retroviral vector N2. The transduced TIL populations were stable and polyclonal with respect to the intact Neo{sup R} gene integration andmore » expressed high levels of neomycin phosphotransferase activity. The Neo{sup R} 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 {beta}- and {gamma}-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 {beta} and {gamma} chains following transduction and selection of TILs in the neomycin analog G418. Human TILs expressed mRNA for tumor necrosis factors ({alpha} and {beta}) 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.« less

  4. Engineered Salmonella enterica serovar Typhimurium overcomes limitations of anti-bacterial immunity in bacteria-mediated tumor therapy

    PubMed Central

    Felgner, Sebastian; Kocijancic, Dino; Frahm, Michael; Heise, Ulrike; Rohde, Manfred; Zimmermann, Kurt; Falk, Christine; Weiss, Siegfried

    2018-01-01

    ABSTRACT Cancer is one of the leading causes of death in the industrialized world and represents a tremendous social and economic burden. As conventional therapies fail to provide a sustainable cure for most cancer patients, the emerging unique immune therapeutic approach of bacteria-mediated tumor therapy (BMTT) is marching towards a feasible solution. Although promising results have been obtained with BMTT using various preclinical tumor models, for advancement a major concern is immunity against the bacterial vector itself. Pre-exposure to the therapeutic agent under field conditions is a reasonable expectation and may limit the therapeutic efficacy of BMTT. In the present study, we investigated the therapeutic potential of Salmonella and E. coli vector strains in naïve and immunized tumor bearing mice. Pre-exposure to the therapeutic agent caused a significant aberrant phenotype of the microenvironment of colonized tumors and limited the in vivo efficacy of established BMTT vector strains Salmonella SL7207 and E. coli Symbioflor-2. Using targeted genetic engineering, we generated the optimized auxotrophic Salmonella vector strain SF200 (ΔlpxR9 ΔpagL7 ΔpagP8 ΔaroA ΔydiV ΔfliF) harboring modifications in Lipid A and flagella synthesis. This combination of mutations resulted in an increased immune-stimulatory capacity and as such the strain was able to overcome the efficacy-limiting effects of pre-exposure. Thus, we conclude that any limitations of BMTT concerning anti-bacterial immunity may be countered by strategies that optimize the immune-stimulatory capacity of the attenuated vector strains. PMID:29308303

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

    PubMed Central

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

    2014-01-01

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

  6. A novel T cell receptor single-chain signaling complex mediates antigen-specific T cell activity and tumor control.

    PubMed

    Stone, Jennifer D; Harris, Daniel T; Soto, Carolina M; Chervin, Adam S; Aggen, David H; Roy, Edward J; Kranz, David M

    2014-11-01

    Adoptive transfer of genetically modified T cells to treat cancer has shown promise in several clinical trials. Two main strategies have been applied to redirect T cells against cancer: (1) introduction of a full-length T cell receptor (TCR) specific for a tumor-associated peptide-MHC, or (2) introduction of a chimeric antigen receptor, including an antibody fragment specific for a tumor cell surface antigen, linked intracellularly to T cell signaling domains. Each strategy has advantages and disadvantages for clinical applications. Here, we present data on the in vitro and in vivo effectiveness of a single-chain signaling receptor incorporating a TCR variable fragment as the targeting element (referred to as TCR-SCS). This receptor contained a single-chain TCR (Vα-linker-Vβ) from a high-affinity TCR called m33, linked to the intracellular signaling domains of CD28 and CD3ζ. This format avoided mispairing with endogenous TCR chains and mediated specific T cell activity when expressed in either CD4 or CD8 T cells. TCR-SCS-transduced CD8-negative cells showed an intriguing sensitivity, compared to full-length TCRs, to higher densities of less stable pepMHC targets. T cells that expressed this peptide-specific receptor persisted in vivo, and exhibited polyfunctional responses. Growth of metastatic antigen-positive tumors was significantly inhibited by T cells that expressed this receptor, and tumor cells that escaped were antigen-loss variants. TCR-SCS receptors represent an alternative targeting receptor strategy that combines the advantages of single-chain expression, avoidance of TCR chain mispairing, and targeting of intracellular antigens presented in complex with MHC proteins.

  7. Singlet oxygen explicit dosimetry to predict long-term local tumor control for BPD-mediated photodynamic therapy

    NASA Astrophysics Data System (ADS)

    Kim, Michele M.; Penjweini, Rozhin; Ong, Yi Hong; Zhu, Timothy C.

    2017-02-01

    Photodynamic therapy (PDT) is a well-established treatment modality for cancer and other malignant diseases; however, quantities such as light fluence, photosensitizer photobleaching rate, and PDT dose do not fully account for all of the dynamic interactions between the key components involved. In particular, fluence rate (Φ) effects are not accounted for, which has a large effect on the oxygen consumption rate. In this preclinical study, reacted singlet oxygen [1O2]rx was investigated as a dosimetric quantity for PDT outcome. The ability of [1O2]rx to predict the long-term local tumor control rate (LCR) for BPD-mediated PDT was examined. Mice bearing radioactivelyinduced fibrosarcoma (RIF) tumors were treated with different in-air fluences (250, 300, and 350 J/cm2) and in-air ϕ (75, 100, and150 mW/cm2) with a BPD dose of 1 mg/kg and a drug-light interval of 3 hours. Treatment was delivered with a collimated laser beam of 1 cm diameter at 690 nm. Explicit dosimetry of initial tissue oxygen concentration, tissue optical properties, and BPD concentration was used to calculate [1O2]rx. Φ was calculated for the treatment volume based on Monte-Carlo simulations and measured tissue optical properties. Kaplan-Meier analyses for LCR were done for an endpoint of tumor volume <= 100 mm3 using four dose metrics: light fluence, photosensitizer photobleaching rate, PDT dose, and [1O2]rx. PDT dose was defined as the product of the timeintegral of photosensitizer concentration and Φ at a 3 mm tumor depth. Preliminary studies show that [1O2]rx better correlates with LCR and is an effective dosimetric quantity that can predict treatment outcome.

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

    PubMed Central

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

    2017-01-01

    Opioid tolerance and the potential for addiction is a significant burden associated with pain management, yet its precise underlying mechanism and prevention remain elusive. Immune signaling contributes to the decreased efficacy of opioids, and we recently demonstrated that Toll-like receptor 4 (TLR4)-mediated neuroinflammation in the periaqueductal gray (PAG) drives tolerance. Tumor necrosis factor (TNF), a product of TLR4 signaling, promotes inflammation and facilitates glutamatergic signaling, key components of opioid tolerance. Therefore, we hypothesize that TLR4-mediated opioid tolerance requires TNF signaling. By expression of a dominant-negative TNF peptide via lentiviral vector injection in rat PAG to sequester soluble TNF (solTNF), we demonstrate that solTNF mediates morphine tolerance induced by TLR4 signaling, stimulates neuroinflammation (increased IL-1β and TLR4 mRNA), and disrupts glutamate reuptake (decreased GLT-1 and GLAST mRNA). We further demonstrate the efficacy of the brain-permeant PEGylated version of the anti-solTNF peptide, XPro1595, injected systemically, to normalize morphine-induced CNS neuroinflammation and morphine- and endotoxin-induced changes in glutamate transport, effectively preserving the efficacy of morphine analgesia and eliminating tolerance. Our findings provide a novel pharmacological target for the prevention of opioid-induced immune signaling, tolerance, and addiction. PMID:27461080

  9. JNK-NQO1 axis drives TAp73-mediated tumor suppression upon oxidative and proteasomal stress.

    PubMed

    Kostecka, A; Sznarkowska, A; Meller, K; Acedo, P; Shi, Y; Mohammad Sakil, H A; Kawiak, A; Lion, M; Królicka, A; Wilhelm, M; Inga, A; Zawacka-Pankau, J

    2014-10-23

    Hyperproliferating cancer cells produce energy mainly from aerobic glycolysis, which results in elevated ROS levels. Thus aggressive tumors often possess enhanced anti-oxidant capacity that impedes many current anti-cancer therapies. Additionally, in ROS-compromised cancer cells ubiquitin proteasome system (UPS) is often deregulated for timely removal of oxidized proteins, thus enabling cell survival. Taken that UPS maintains the turnover of factors controlling cell cycle and apoptosis--such as p53 or p73, it represents a promising target for pharmaceutical intervention. Enhancing oxidative insult in already ROS-compromised cancer cells appears as an attractive anti-tumor scenario. TAp73 is a bona fide tumor suppressor that drives the chemosensitivity of some cancers to cisplatin or γ-radiation. It is an important drug target in tumors where p53 is lost or mutated. Here we discovered a novel synergistic mechanism leading to potent p73 activation and cancer cell death by oxidative stress and inhibition of 20S proteasomes. Using a small-molecule inhibitor of 20S proteasome and ROS-inducer--withaferin A (WA), we found that WA-induced ROS activates JNK kinase and stabilizes phase II anti-oxidant response effector NF-E2-related transcription factor (NRF2). This results in activation of Nrf2 target--NQO1 (NADPH quinone oxidoreductase), and TAp73 protein stabilization. The observed effect was ablated by the ROS scavenger--NAC. Concurrently, stress-activated JNK phosphorylates TAp73 at multiple serine and threonine residues, which is crucial to ablate TAp73/MDM2 complex and to promote TAp73 transcriptional function and induction of robust apoptosis. Taken together our data demonstrate that ROS insult in combination with the inhibition of 20S proteasome and TAp73 activation endows synthetic lethality in cancer cells. Thus, our results may enable the establishment of a novel pharmacological strategy to exploit the enhanced sensitivity of tumors to elevated ROS and

  10. A novel inhibitor of proteasome deubiquitinating activity renders tumor cells sensitive to TRAIL-mediated apoptosis by natural killer cells and T cells.

    PubMed

    Sarhan, Dhifaf; Wennerberg, Erik; D'Arcy, Padraig; Gurajada, Deepthy; Linder, Stig; Lundqvist, Andreas

    2013-08-01

    The proteasome inhibitor bortezomib simultaneously renders tumor cells sensitive to killing by natural killer (NK) cells and resistant to killing by tumor-specific T cells. Here, we show that b-AP15, a novel inhibitor of proteasome deubiquitinating activity, sensitizes tumors to both NK and T cell-mediated killing. Exposure to b-AP15 significantly increased the susceptibility of tumor cell lines of various origins to NK (p < 0.0002) and T cell (p = 0.02)-mediated cytotoxicity. Treatment with b-AP15 resulted in increased tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) receptor-2 expression (p = 0.03) and decreased cFLIP expression in tumor cells in vitro. In tumor-bearing SCID/Beige mice, treatment with b-AP15 followed by infusion of either human NK cells or tumor-specific T cells resulted in a significantly delayed tumor progression compared with mice treated with NK cells (p = 0.006), T cells (p < 0.0001) or b-AP15 alone (p = 0.003). Combined infusion of NK and T cells in tumor-bearing BALB/c mice following treatment with b-AP15 resulted in a significantly prolonged long-term survival compared with mice treated with b-AP15 and NK or T cells (p ≤ 0.01). Our findings show that b-AP15-induced sensitization to TRAIL-mediated apoptosis could be used as a novel strategy to augment the anticancer effects of adoptively infused NK and T cells in patients with cancer.

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

    PubMed Central

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

    2015-01-01

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

  12. Annexin II-Mediated Ca++ Influx Regulates Endothelial Cell (EC) Apoptosis and Tumor Angiogenesis

    DTIC Science & Technology

    2005-10-01

    strategies. J Cell Biol, 152: 777-784, 2001. 20. Rifkin, D. B., Mazzieri, R ., Munger, J . S., Noguera , I., and Sung, J . Proteolytic control of growth...independent prognostic indicator in early-stage breast carcinoma. J Natl Cancer Inst, 84: 1875-1887, 1992 . 3. Weidner, N. and Folkman, J . Tumoral...angiostatin binding protein in endothelial cells. J of Surgical Research, 86, 1999. 14. Tuszynski, G. P., Sharma, M. R ., Rothman, V. L., and Sharna, M. C

  13. NQO1-mediated tumor-selective lethality and radiosensitization for head and neck cancer

    PubMed Central

    Li, Long-Shan; Reddy, Srilakshmi; Lin, Zhen-Hua; Liu, Shuangping; Park, Hyunsil; Chun, Stephen G.; Bornmann, William G.; Thibodeaux, Joel; Yan, Jingsheng; Chakrabarti, Gaurab; Xie, Xian-Jin; Sumer, Baran D.; Boothman, David A.; Yordy, John S.

    2016-01-01

    Ionizing radiation (IR) is a key therapeutic regimen for many head and neck cancers (HNCs). However, the 5-year overall survival rate for locally-advanced HNCs is ∼50% and better therapeutic efficacy is needed. NAD(P)H:quinone oxidoreductase 1 (NQO1) is over-expressed in many cancers, and β-lapachone (β-lap), an unique NQO1 bioactivatable drug, exploits this enzyme to release massive reactive oxygen species (ROS) levels that synergizes with IR to kill by programmed necrosis. β-Lap represents a novel therapeutic opportunity in HNC leading to tumor-selective lethality that will enhance the efficacy of ionizing radiation. Immunohistochemical staining and western blot assays were used to assess the expression levels of NQO1 in HNC cells and tumors. Forty-five percent of endogenous HNCs express elevated NQO1 levels. In addition, multiple HNC cell lines and tumors demonstrated elevated levels of NQO1 expression and activity and were tested for anticancer lethality and radiosensitization by β-lap using long-term survival assays. The combination of nontoxic β-lap doses and IR significantly enhanced NQO1-dependenttumor cell lethality, increased ROS, TUNEL positive cells, DNA damage, NAD+ and adenosine triphosphate (ATP) consumption, and resulted in significantantitumor efficacy and prolonged survival in two xenograft murine HNC models, demonstrating β-Lap radiosensitization of HNCs through a NQO1-dependent mechanism. This translational study offers a potential biomarker-driven strategy using NQO1 expression to select tumors susceptible to β-lap-induced radiosensitization. PMID:27196777

  14. Microtubule-mediated transport of the tumor-suppressor protein Merlin and its mutants.

    PubMed

    Benseñor, Lorena B; Barlan, Kari; Rice, Sarah E; Fehon, Richard G; Gelfand, Vladimir I

    2010-04-20

    The neurofibromatosis type 2 (NF2) tumor-suppressor protein Merlin is a member of the ERM family of proteins that links the cytoskeleton to the plasma membrane. In humans, mutations in the NF2 gene cause neurofibromatosis type-2 (NF2), a cancer syndrome characterized by the development of tumors of the nervous system. Previous reports have suggested that the subcellular distribution of Merlin is critical to its function, and that several NF2 mutants that lack tumor-suppressor activity present improper localization. Here we used a Drosophila cell culture model to study the distribution and mechanism of intracellular transport of Merlin and its mutants. We found that Drosophila Merlin formed cytoplasmic particles that move bidirectionally along microtubules. A single NF2-causing amino acid substitution in the FERM domain dramatically inhibited Merlin particle movement. Surprisingly, the presence of this immotile Merlin mutant also inhibited trafficking of the WT protein. Analysis of the movement of WT protein using RNAi and pull-downs showed that Merlin particles are associated with and moved by microtubule motors (kinesin-1 and cytoplasmic dynein), and that binding of motors and movement is regulated by Merlin phosphorylation. Inhibition of Merlin transport by expression of the dominant-negative mutant or depletion of kinesin-1 results in increased nuclear accumulation of the transcriptional coactivator Yorkie. These results demonstrate the requirement of microtubule-dependent transport for Merlin function.

  15. IL-17-Dependent, IFN-γ-Independent Tumor Rejection is Mediated by Cytotoxic T Lymphocytes and Occurs at Extraocular Sites, but is Excluded from the Eye

    PubMed Central

    Coursey, Terry G.; Chen, Peter W.; Niederkorn, Jerry Y.

    2011-01-01

    Although intraocular tumors reside in an immune privileged site where immune responses are suppressed, some tumors are rejected nonetheless. An example of this is the rejection of intraocular adenovirus-induced (Ad5E1) tumors in C57BL/6 mice. We previously identified an Ad5E1 tumor clone in which the rejection is IFN-γ-dependent and culminates in the destruction of both the tumor and the eye. Although Ad5E1 tumors are not rejected when transplanted into the eyes of IFN-γ KO mice, they are rejected following subcutaneous transplantation (SC). Thus, outside of the eye Ad5E1 tumors elicit a form of tumor immunity that is IFN-γ-independent. Here, we demonstrate that IFN-γ-independent SC rejection requires both CD4+ and CD8+ T cells. Furthermore, SC tumor rejection requires IL-17, which is produced by IFN-γ-deficient CD4+ T cells in response to tumor antigens (TAs). Splenocytes from CD4-depleted IFN-γ KO mice produce significantly less IL-17 compared to splenocytes from isotype-treated IFN-γ KO animals in response to TAs. Furthermore, depletion of IL-17 decreases CTL activity against Ad5E1 tumor cells. In this model we propose that in the absence of IFN-γ, CD4+ T cells produce IL-17 in response to TAs, which increases CTL activity that mediates tumor rejection. However, this does not occur in the eye. IL-6 production within the eye is severely reduced, which is consistent with the failure to induce Th17 cells within the intraocular tumors. By contrast, the SC environment is replete with IL-6 and supports the induction of Th17 cells. Therefore, IFN-γ-independent tumor rejection is excluded from the eye and may represent a newly recognized form of ocular immune privilege. PMID:21918192

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

    PubMed Central

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

    2017-01-01

    Metastasis requires tumor cells to navigate through a stiff stroma and squeeze through confined microenvironments. Whether tumors exploit unique biophysical properties to metastasize remains unclear. Data show that invading mammary tumor cells, when cultured in a stiffened three-dimensional extracellular matrix that recapitulates the primary tumor stroma, adopt a basal-like phenotype. Metastatic tumor cells and basal-like tumor cells exert higher integrin-mediated traction forces at the bulk and molecular levels, consistent with a motor-clutch model in which motors and clutches are both increased. Basal-like nonmalignant mammary epithelial cells also display an altered integrin adhesion molecular organization at the nanoscale and recruit a suite of paxillin-associated proteins implicated in invasion and metastasis. Phosphorylation of paxillin by Src family kinases, which regulates adhesion turnover, is similarly enhanced in the metastatic and basal-like tumor cells, fostered by a stiff matrix, and critical for tumor cell invasion in our assays. Bioinformatics reveals an unappreciated relationship between Src kinases, paxillin, and survival of breast cancer patients. Thus adoption of the basal-like adhesion phenotype may favor the recruitment of molecules that facilitate tumor metastasis to integrin-based adhesions. Analysis of the physical properties of tumor cells and integrin adhesion composition in biopsies may be predictive of patient outcome. PMID:28381423

  17. Ankyrin Repeat and SOCS Box 3 (ASB3) Mediates Ubiquitination and Degradation of Tumor Necrosis Factor Receptor II

    PubMed Central

    Chung, Alicia S.; Guan, Ying-jie; Yuan, Zheng-Long; Albina, Jorge E.; Chin, Y. Eugene

    2005-01-01

    Ankyrin repeat and SOCS box (ASB) family members have a C-terminal SOCS box and an N-terminal ankyrin-related sequence of variable repeats belonging to the SOCS superfamily. While SH2-domain-bearing SOCS proteins are mainly involved in the negative feedback regulation of the protein tyrosine kinase-STAT pathway in response to a variety of cytokines, the roles of ASB family members remain largely unknown. To investigate ASB functions, we screened for ASB3-interacting factors by using antibody array technology and identified tumor necrosis factor receptor II (TNF-R2) as an ASB3 binding target. ASB3 expression and activities are required for (i) TNF-R2 ubiquitination both in vivo and in vitro, (ii) TNF-R2 proteolysis via the proteasome pathway, and (iii) the inhibition of TNF-R2-mediated Jun N-terminal protein kinase (JNK) activation. While the ankyrin repeats of ASB3 interact with the C-terminal 37 amino acids of TNF-R2, the SOCS box of ASB3 is responsible for recruiting the E3 ubiquitin ligase adaptors Elongins-B/C, leading to TNF-R2 ubiquitination on multiple lysine residues within its C-terminal region. Downregulation of ASB3 expression by a small interfering RNA inhibited TNF-R2 degradation and potentiated TNF-R2-mediated cytotoxicity. The data presented here implicate ASB3 as a negative regulator of TNF-R2-mediated cellular responses to TNF-α by direct targeting of TNF-R2 for ubiquitination and proteasome-mediated degradation. PMID:15899873

  18. Shiga Toxin 1-Induced Inflammatory Response in Lipopolysaccharide-Sensitized Astrocytes Is Mediated by Endogenous Tumor Necrosis Factor Alpha▿

    PubMed Central

    Landoni, Verónica I.; de Campos-Nebel, Marcelo; Schierloh, Pablo; Calatayud, Cecilia; Fernandez, Gabriela C.; Ramos, M. Victoria; Rearte, Bárbara; Palermo, Marina S.; Isturiz, Martín A.

    2010-01-01

    Hemolytic-uremic syndrome (HUS) is generally caused by Shiga toxin (Stx)-producing Escherichia coli. Endothelial dysfunction mediated by Stx is a central aspect in HUS development. However, inflammatory mediators such as bacterial lipopolysaccharide (LPS) and polymorphonuclear neutrophils (PMN) contribute to HUS pathophysiology by potentiating Stx effects. Acute renal failure is the main feature of HUS, but in severe cases, patients can develop neurological complications, which are usually associated with death. Although the mechanisms of neurological damage remain uncertain, alterations of the blood-brain barrier associated with brain endothelial injury is clear. Astrocytes (ASTs) are the most abundant inflammatory cells of the brain that modulate the normal function of brain endothelium and neurons. The aim of this study was to evaluate the effects of Stx type 1 (Stx1) alone or in combination with LPS in ASTs. Although Stx1 induced a weak inflammatory response, pretreatment with LPS sensitized ASTs to Stx1-mediated effects. Moreover, LPS increased the level of expression of the Stx receptor and its internalization. An early inflammatory response, characterized by the release of tumor necrosis factor alpha (TNF-α) and nitric oxide and PMN-chemoattractant activity, was induced by Stx1 in LPS-sensitized ASTs, whereas activation, evidenced by higher levels of glial fibrillary acid protein and cell death, was induced later. Furthermore, increased adhesion and PMN-mediated cytotoxicity were observed after Stx1 treatment in LPS-sensitized ASTs. These effects were dependent on NF-κB activation or AST-derived TNF-α. Our results suggest that TNF-α is a pivotal effector molecule that amplifies Stx1 effects on LPS-sensitized ASTs, contributing to brain inflammation and leading to endothelial and neuronal injury. PMID:20008539

  19. An ARF-independent c-Myc-activated tumor suppression pathway mediated by ribosomal protein-Mdm2 interaction

    PubMed Central

    Macias, Everardo; Jin, Aiwen; Deisenroth, Chad; Bhat, Krishna; Mao, Hua; Lindström, Mikael S.; Zhang, Yanping

    2013-01-01

    Summary In vitro studies have shown that inhibition of ribosomal biogenesis can activate p53 through ribosomal protein (RP)-mediated suppression of Mdm2 E3 ligase activity. To study the physiological significance of the RP-Mdm2 interaction, we generated mice carrying a cancer-associated cysteine-to-phenylalanine substitution in the zinc finger of Mdm2 that disrupted its binding to RPL5 and RPL11. Mice harboring this mutation, although retain normal p53 response to DNA damage, lack p53 response to perturbations in ribosome biogenesis. Loss of RP-Mdm2 interaction significantly accelerates Eμ-Myc induced lymphomagenesis. Furthermore, ribosomal perturbation induced p53 response does not require tumor suppressor p19Arf. Collectively, our findings establish RP-Mdm2 interaction as a genuine p53 stress-signaling pathway activated by aberrant ribosomal biogenesis and essential for safeguarding against oncogenic c-Myc-induced tumorigenesis. PMID:20832751

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

    PubMed

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

    2016-10-01

    Glioblastomas are characterized by transcriptionally distinct subtypes, but despite possible clinical relevance, their regulation remains poorly understood. The commonly used molecular classification systems for GBM all identify a subtype with high expression of mesenchymal marker transcripts, strongly associated with invasive growth. We used a comprehensive data-driven network modeling technique (augmented sparse inverse covariance selection, aSICS) to define separate genomic, epigenetic, and transcriptional regulators of glioblastoma subtypes. Our model identified Annexin A2 (ANXA2) as a novel methylation-controlled positive regulator of the mesenchymal subtype. Subsequent evaluation in two independent cohorts established ANXA2 expression as a prognostic factor that is dependent on ANXA2 promoter methylation. ANXA2 knockdown in primary glioblastoma stem cell-like cultures suppressed known mesenchymal master regulators, and abrogated cell proliferation and invasion. Our results place ANXA2 at the apex of a regulatory cascade that determines glioblastoma mesenchymal transformation and validate aSICS as a general methodology to uncover regulators of cancer subtypes. Copyright © 2016. Published by Elsevier B.V.

  1. A 2-Oxoglutarate-Dependent Dioxygenase Mediates the Biosynthesis of Glucoraphasatin in Radish1[OPEN

    PubMed Central

    Kitashiba, Hiroyasu; Li, Feng; Fukino, Nobuko; Ohara, Takayoshi; Nishio, Takeshi; Ishida, Masahiko

    2017-01-01

    Glucosinolates (GSLs) are secondary metabolites whose degradation products confer intrinsic flavors and aromas to Brassicaceae vegetables. Several structures of GSLs are known in the Brassicaceae, and the biosynthetic pathway and regulatory networks have been elucidated in Arabidopsis (Arabidopsis thaliana). GSLs are precursors of chemical defense substances against herbivorous pests. Specific GSLs can act as feeding blockers or stimulants, depending on the pest species. Natural selection has led to diversity in the GSL composition even within individual species. However, in radish (Raphanus sativus), glucoraphasatin (4-methylthio-3-butenyl glucosinolate) accounts for more than 90% of the total GSLs, and little compositional variation is observed. Because glucoraphasatin is not contained in other members of the Brassicaceae, like Arabidopsis and cabbage (Brassica oleracea), the biosynthetic pathways for glucoraphasatin remain unclear. In this report, we identified and characterized a gene encoding GLUCORAPHASATIN SYNTHASE 1 (GRS1) by genetic mapping using a mutant that genetically lacks glucoraphasatin. Transgenic Arabidopsis, which overexpressed GRS1 cDNA, accumulated glucoraphasatin in the leaves. GRS1 encodes a 2-oxoglutarate-dependent dioxygenase, and it is abundantly expressed in the leaf. To further investigate the biosynthesis and transportation of GSLs in radish, we grafted a grs1 plant onto a wild-type plant. The grafting experiment revealed a leaf-to-root long-distance glucoraphasatin transport system in radish and showed that the composition of GSLs differed among the organs. Based on these observations, we propose a characteristic biosynthesis pathway for glucoraphasatin in radish. Our results should be useful in metabolite engineering for breeding of high-value vegetables. PMID:28100450

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

    PubMed Central

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

    2016-01-01

    Tumor cells are confronted to a type I collagen rich environment which regulates cell proliferation and invasion. Biological aging has been associated with structural changes of type I collagen. Here, we address the effect of collagen aging on cell proliferation in a three-dimensional context (3D). We provide evidence for an inhibitory effect of adult collagen, but not of the old one, on proliferation of human fibrosarcoma HT-1080 cells. This effect involves both the activation of the tyrosine kinase Discoidin Domain Receptor 2 (DDR2) and the tyrosine phosphatase SHP-2. DDR2 and SHP-2 were less activated in old collagen. DDR2 inhibition decreased SHP-2 phosphorylation in adult collagen and increased cell proliferation to a level similar to that observed in old collagen. In the presence of old collagen, a high level of JAK2 and ERK1/2 phosphorylation was observed while expression of the cell cycle negative regulator p21CIP1 was decreased. Inhibition of DDR2 kinase function also led to an increase in ERK1/2 phosphorylation and a decrease in p21CIP1 expression. Similar signaling profile was observed when DDR2 was inhibited in adult collagen. Altogether, these data suggest that biological collagen aging could increase tumor cell proliferation by reducingthe activation of the key matrix sensor DDR2. PMID:27121132

  3. [Tumor cell targetability of folate receptor-mediated mitoxantrone albumin nanoparticles].

    PubMed

    Zhang, Liang-ke; Hou, Shi-xiang; Mao, Sheng-jun; Wei, Da-peng; Song, Xiang-rong

    2006-01-01

    To study the tumor cell targetability of folate-conjugated mitoxantone-loaded albumin nanoparticles (MTO-BSANP-folate). Bovine albumin nanoparticles were prepared by desolvation method. The activated folic acid (N-hydroxysuccinimide ester of folic acid) was conjuated to the surface of BSANP via the amino groups. The MTO-BSANP-folate was prepared by mixing folate-conjugated albumin nanoparticles with mitoxantrone and then cross-linked by glutaraldehyde. 3HTdR and flow cytometry were used to evaluate the targetability of MTO-BSANP-folate. The encapsulation rate of folate-conjugated mitoxantrone albumin nanoparticles was (96.55 +/- 0.96)% and the drug loading was (9.66 +/- 0.10)%. The results of 3HTdR showed that the efficacy of MTO-BSANP-folate in killing SKOV3 cells was higher than that of MTO-BSANP-folate, and the results of flow cytometry showed that the apoptosis-promoting effect of MTO-BSANP-folate was 3.5-4.5 times higher than that of MTO-BSANP. MTO-BSANP-folate could be targeted, via folate receptor, to the tumor cells rich in folate receptors.

  4. α-Mangostin Reduced ER Stress-mediated Tumor Growth through Autophagy Activation.

    PubMed

    Kim, Sung-Jin; Hong, Eun-Hye; Lee, Bo-Ra; Park, Moon-Ho; Kim, Ji-Won; Pyun, A-Rim; Kim, Yeon-Jeong; Chang, Sun-Young; Chin, Young-Won; Ko, Hyun-Jeong

    2012-12-01

    α-Mangostin is a xanthon derivative contained in the fruit hull of mangosteen (Garcinia mangostana L.), and the administration of α-Mangostin inhibited the growth of transplanted colon cancer, Her/CT26 cells which expressed Her-2/neu as tumor antigen. Although α-Mangostin was reported to have inhibitory activity against sarco/endoplasmic reticulum Ca(2+) ATPase like thapsigargin, it showed different activity for autophagy regulation. In the current study, we found that α-Mangostin induced autophagy activation in mouse intestinal epithelial cells, as GFP-LC3 transgenic mice were orally administered with 20 mg/kg of α-Mangostin daily for three days. However, the activation of autophagy by α-Mangostin did not significantly increase OVA-specific T cell proliferation. As we assessed ER stress by using XBP-1 reporter system and phosphorylation of eIF2α, thapsigargin-induced ER stress was significantly reduced by α-Mangostin. However, coadministration of thapsigargin with α-Mangostin completely blocked the antitumor activity of α-Mangostin, suggesting ER stress with autophagy blockade accelerated tumor growth in mouse colon cancer model. Thus the antitumor activity of α-Mangostin can be ascribable to the autophagy activation rather than ER stress induction.

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

    PubMed Central

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

    2010-01-01

    Parafibromin, a component of the RNA polymerase II-associated PAF1 complex, is a tumor suppressor linked to hyperparathyroidism-jaw tumor syndrome and sporadic parathyroid carcinoma. Parafibromin induces cell cycle arrest by repressing cyclin D1 via an unknown mechanism. Here, we show that parafibromin interacts with the histone methyltransferase, SUV39H1, and functions as a transcriptional repressor. The central region (128–227 amino acids) of parafibromin is important for both the interaction with SUV39H1 and transcriptional repression. Parafibromin associated with the promoter and coding regions of cyclin D1 and was required for the recruitment of SUV39H1 and the induction of H3 K9 methylation but not H3 K4 methylation. RNA interference analysis showed that SUV39H1 was critical for cyclin D1 repression. These data suggest that parafibromin plays an unexpected role as a repressor in addition to its widely known activity associated with transcriptional activation. Parafibromin as a part of the PAF1 complex might downregulate cyclin D1 expression by integrating repressive H3 K9 methylation during transcription. PMID:19906718

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

    PubMed

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

    2010-01-01

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

  7. Mosaic analysis and tumor induction in zebrafish by microsatellite instability-mediated stochastic gene expression.

    PubMed

    Koole, Wouter; Tijsterman, Marcel

    2014-07-01

    Mosaic analysis, in which two or more populations of cells with differing genotypes are studied in a single animal, is a powerful approach to study developmental mechanisms and gene function in vivo. Over recent years, several genetic methods have been developed to achieve mosaicism in zebrafish, but despite their advances, limitations remain and different approaches and further refinements are warranted. Here, we describe an alternative approach for creating somatic mosaicism in zebrafish that relies on the instability of microsatellite sequences during replication. We placed the coding sequences of various marker proteins downstream of a microsatellite and out-of-frame; in vivo frameshifting into the proper reading frame results in expression of the protein in random individual cells that are surrounded by wild-type cells. We optimized this approach for the binary Gal4-UAS expression system by generating a driver line and effector lines that stochastically express Gal4-VP16 or UAS:H2A-EGFP and self-maintaining UAS:H2A-EGFP-Kaloop, respectively. To demonstrate the utility of this system, we stochastically expressed a constitutively active form of the human oncogene H-RAS and show the occurrence of hyperpigmentation and sporadic tumors within 5 days. Our data demonstrate that inducing somatic mosaicism through microsatellite instability can be a valuable approach for mosaic analysis and tumor induction in Danio rerio. © 2014. Published by The Company of Biologists Ltd.

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

    PubMed

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

    2016-05-03

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

  9. MicroRNA-140 mediates RB tumor suppressor function to control stem cell-like activity through interleukin-6

    PubMed Central

    Yoshida, Akiyo; Kitajima, Shunsuke; Li, Fengkai; Cheng, Chaoyang; Takegami, Yujiro; Kohno, Susumu; Wan, Yuan Song; Hayashi, Naoyuki; Muranaka, Hayato; Nishimoto, Yuuki; Nagatani, Naoko; Nishiuchi, Takumi; Thai, Tran C; Suzuki, Sawako; Nakao, Shinji; Tanaka, Tomoaki; Hirose, Osamu; Barbie, David A.; Takahashi, Chiaki

    2017-01-01

    We established an in vitro cell culture system to determine novel activities of the retinoblastoma (Rb) protein during tumor progression. Rb depletion in p53-null mouse-derived soft tissue sarcoma cells induced a spherogenic phenotype. Cells retrieved from Rb-depleted spheres exhibited slower proliferation and less efficient BrdU incorporation, however, much higher spherogenic activity and aggressive behavior. We discovered six miRNAs, including mmu-miR-18a, -25, -29b, -140, -337, and -1839, whose expression levels correlated tightly with the Rb status and spherogenic activity. Among these, mmu-miR-140 appeared to be positively controlled by Rb and to antagonize the effect of Rb depletion on spherogenesis and tumorigenesis. Furthermore, among genes potentially targeted by mmu-miR-140, Il-6 was upregulated by Rb depletion and downregulated by mmu-mir-140 overexpression. Altogether, we demonstrate the possibility that mmu-mir-140 mediates the Rb function to downregulate Il-6 by targeting its 3′-untranslated region. Finally, we detected the same relationship among RB, hsa-miR-140 and IL-6 in a human breast cancer cell line MCF-7. Because IL-6 is a critical modulator of malignant features of cancer cells and the RB pathway is impaired in the majority of cancers, hsa-miR-140 might be a promising therapeutic tool that disrupts linkage between tumor suppressor inactivation and pro-inflammatory cytokine response. PMID:28099924

  10. MicroRNA-140 mediates RB tumor suppressor function to control stem cell-like activity through interleukin-6.

    PubMed

    Yoshida, Akiyo; Kitajima, Shunsuke; Li, Fengkai; Cheng, Chaoyang; Takegami, Yujiro; Kohno, Susumu; Wan, Yuan Song; Hayashi, Naoyuki; Muranaka, Hayato; Nishimoto, Yuuki; Nagatani, Naoko; Nishiuchi, Takumi; Thai, Tran C; Suzuki, Sawako; Nakao, Shinji; Tanaka, Tomoaki; Hirose, Osamu; Barbie, David A; Takahashi, Chiaki

    2017-02-21

    We established an in vitro cell culture system to determine novel activities of the retinoblastoma (Rb) protein during tumor progression. Rb depletion in p53-null mouse-derived soft tissue sarcoma cells induced a spherogenic phenotype. Cells retrieved from Rb-depleted spheres exhibited slower proliferation and less efficient BrdU incorporation, however, much higher spherogenic activity and aggressive behavior. We discovered six miRNAs, including mmu-miR-18a, -25, -29b, -140, -337, and -1839, whose expression levels correlated tightly with the Rb status and spherogenic activity. Among these, mmu-miR-140 appeared to be positively controlled by Rb and to antagonize the effect of Rb depletion on spherogenesis and tumorigenesis. Furthermore, among genes potentially targeted by mmu-miR-140, Il-6 was upregulated by Rb depletion and downregulated by mmu-mir-140 overexpression. Altogether, we demonstrate the possibility that mmu-mir-140 mediates the Rb function to downregulate Il-6 by targeting its 3'-untranslated region. Finally, we detected the same relationship among RB, hsa-miR-140 and IL-6 in a human breast cancer cell line MCF-7. Because IL-6 is a critical modulator of malignant features of cancer cells and the RB pathway is impaired in the majority of cancers, hsa-miR-140 might be a promising therapeutic tool that disrupts linkage between tumor suppressor inactivation and pro-inflammatory cytokine response.

  11. The tumor antagonistic steroidal alkaloid Solanidine prompts the intrinsic suicidal signal mediated DFF-40 nuclear import and nucleosomal disruption.

    PubMed

    Malojirao, Vikas H; Vigneshwaran, V; Thirusangu, Prabhu; Mahmood, Riaz; Prabhakar, B T

    2018-04-15

    Aim Deformity in the cellular homeostatic event associated with cell survival and apoptosis are committing factors for carcinogenesis. Interventions of these events by pharmacologically active agent gain predominance in cancer treatment. In current investigation Solanidine, a steroidal alkaloid was evaluated on tumorigenesis by targeting death signal using multiple tumor cells and model systems. Anti-proliferative effect was evaluated using cytotoxic studies. Prolonged cytotoxic effect of Solanidine was examined by colony formation assay. Exhibition of apoptotic hallmark induced by Solanidine was examined using FACS analysis, Annexin-V staining, Acridine orange staining, TUNEL assay. Altered gene expression was evaluated using Immunoblot, Immunofluorescence and Immunohistochemistry technique. In-vitro results were revalidated in EAC solid tumor and CAM xenograft model. Solanidine exerts its potential effect in a target specific manner. The cytotoxic/anticlonogenic activity was due to induction of typical cellular apoptotic hallmarks and cell cycle blockage at S-G2/M phase. The molecular events underlying this effect is through activation of intrinsic pathway via Bax, Bad and Cytochrome c activation by neutralizing Bcl-2 expression, along with downregulated PI3K/Akt survival signal. As a consequence, downstream pro apoptogenic gene, active Caspase-3 was over expressed by Solanidine to cleave its substrate PARP and promotes nuclear import of DFF-40. Anti-carcinogenic aptitude was further confirmed by murine solid tumors and in-vivo CAM xenograft studies. Solanidine emerged as active molecule against tomorigenesis by activating nuclear import of DFF-40 mediated nucleosomal disruption and cell demise. It can be developed as a potential apoptogenic small molecule for cancer therapy. Copyright © 2018 Elsevier Inc. All rights reserved.

  12. The Fbw7 tumor suppressor targets KLF5 for ubiquitin-mediated degradation and suppresses breast cell proliferation.

    PubMed

    Zhao, Dong; Zheng, Han-Qiu; Zhou, Zhongmei; Chen, Ceshi

    2010-06-01

    Fbw7 is a tumor suppressor frequently inactivated in cancers. The KLF5 transcription factor promotes breast cell proliferation and tumorigenesis through upregulating FGF-BP. The KLF5 protein degrades rapidly through the ubiquitin proteasome pathway. Here, we show that the Skp1-CUL1-Fbw7 E3 ubiquitin ligase complex (SCF(Fbw7)) targets KLF5 for ubiquitin-mediated degradation in a GSK3beta-mediated KLF5 phosphorylation-dependent manner. Mutation of the critical S303 residue in the KLF5 Cdc4 phospho-degrons motif ((303)SPPSS) abolishes the protein interaction, ubiquitination, and degradation by Fbw7. Inactivation of endogenous Fbw7 remarkably increases the endogenous KLF5 protein abundances. Endogenous Fbw7 suppresses the FGF-BP gene expression and breast cell proliferation through targeting KLF5 for degradation. These findings suggest that Fbw7 inhibits breast cell proliferation at least partially through targeting KLF5 for proteolysis. This new regulatory mechanism of KLF5 degradation may result in useful diagnostic and therapeutic targets for breast cancer and other cancers. Copyright 2010 AACR.

  13. Phase I trial of ISIS 104838, a 2'-methoxyethyl modified antisense oligonucleotide targeting tumor necrosis factor-alpha.

    PubMed

    Sewell, K Lea; Geary, Richard S; Baker, Brenda F; Glover, Josephine M; Mant, Timothy G K; Yu, Rosie Z; Tami, Joseph A; Dorr, F Andrew

    2002-12-01

    ISIS 104838 is a 20-mer phosphorothioate antisense oligonucleotide (ASO) that binds tumor necrosis factor-alpha (TNF-alpha) mRNA. It carries a 2'-methoxyethyl modification on the five 3' and 5' nucleotide sugars, with 10 central unmodified deoxynucleotides. ISIS 104838 was identified from a 264 ASO screen in phorbol myristate acetate-activated keratinocytes, and the dose response was assessed in lipopolysaccharide (LPS)-activated monocytes. Healthy males received multiple intravenous (i.v.) ISIS 104838 infusions in a placebo-controlled dose escalation trial (0.1-6 mg/kg). Additional volunteers received single or multiple subcutaneous (s.c.) injections. ISIS 104838 suppressed TNF-alpha protein by 85% in stimulated keratinocytes. The IC50 for TNF-alpha mRNA inhibition in stimulated monocytes was <1 microM. For i.v., C(max) occurred at the end of infusion. The effective plasma half-life was 15 to 45 min at 0.1 to 0.5 mg/kg and 1 to 1.8 h for higher doses. The apparent terminal plasma elimination half-life approximated 25 days. Obese subjects had higher plasma levels following equivalent mg/kg doses. For s.c. injections, C(max) occurred at 2 to 4 h and was lower than with equivalent i.v. dosing. Plasma bioavailability compared with i.v. was 82% following a 200 mg/ml s.c. injection. Transient activated partial thromboplastin time prolongation occurred after i.v. infusions and minimally after s.c. injections. Two subjects experienced rash, one a reversible platelet decrease, and mild injection site tenderness was noted. TNF-alpha production by peripheral blood leukocytes, induced ex vivo by LPS, was decreased by ISIS 104838 (p < 0.01). ISIS 104838, a second-generation antisense oligonucleotide, was generally well tolerated intravenously and subcutaneously. The pharmacokinetics support an infrequent dosing interval. Inhibition of TNF-alpha production ex vivo was demonstrated.

  14. Tumor-Targeting of EGFR Inhibitors by Hypoxia-Mediated Activation**

    PubMed Central

    Kryeziu, Kushtrim; Pichler, Verena; Roller, Alexander; Berger, Walter; Heffeter, Petra; Kowol, Christian R.

    2015-01-01

    The development of receptor tyrosine-kinase inhibitors (TKIs) was a major step forward in cancer treatment. However, the therapy with TKIs is limited by strong side effects and drug resistance. The aim of this study was the design of novel epidermal growth factor receptor (EGFR) inhibitors that are specifically activated in malignant tissue. Thus, a CoIII-based prodrug strategy for the targeted release of an EGFR inhibitor triggered by hypoxia in the solid tumor was used. New inhibitors with chelating moieties were prepared and tested for their EGFR-inhibitory potential. The most promising candidate was coupled to CoIII and the biological activity tested in cell culture. Indeed, hypoxic activation and subsequent EGFR inhibition was proven. Finally, the compound was tested in vivo, also revealing potent anticancer activity. PMID:25079700

  15. XEDAR as a putative colorectal tumor suppressor that mediates p53-regulated anoikis pathway.

    PubMed

    Tanikawa, C; Furukawa, Y; Yoshida, N; Arakawa, H; Nakamura, Y; Matsuda, K

    2009-08-27

    Colorectal cancers with mutations in the p53 gene have an invasive property, but its underlying mechanism is not fully understood. Through the screening of two data sets of the genome-wide expression profile, one for p53-introduced cells and the other for the numbers of cancer tissues, we report here X-linked ectodermal dysplasia receptor (XEDAR), a member of the TNFR superfamily, as a novel p53 target that has a crucial role in colorectal carcinogenesis. p53 upregulated XEDAR expression through two p53-binding sites within intron 1 of the XEDAR gene. We also found a significant correlation between decreased XEDAR expressions and p53 gene mutations in breast and lung cancer cell lines (P=0.0043 and P=0.0122, respectively). Furthermore, promoter hypermethylation of the XEDAR gene was detected in 20 of 20 colorectal cancer cell lines (100%) and in 6 of 12 colorectal cancer tissues (50%), respectively. Thus, the XEDAR expression was suppressed to <25% of surrounding normal tissues in 12 of 18 colorectal cancer tissues (66.7%) due to either its epigenetic alterations and/or p53 mutations. We also found that XEDAR interacted with and subsequently caused the accumulation of FAS protein, another member of p53-inducible TNFR. Moreover, XEDAR negatively regulated FAK, a central component of focal adhesion. As a result, inactivation of XEDAR resulted in the enhancement of cell adhesion and spreading, as well as resistance to p53-induced apoptosis. Taken together, our findings showed that XEDAR is a putative tumor suppressor that could prevent malignant transformation and tumor progression by regulating apoptosis and anoikis.

  16. Tumor necrosis factor mediates temporomandibular joint bone tissue resorption in rheumatoid arthritis.

    PubMed

    Ahmed, Neveen; Petersson, Arne; Catrina, Anca Irinel; Mustafa, Hamid; Alstergren, Per

    2015-04-01

    To investigate if TNF, IL-1 or their endogenous controls, in relation to ACPA, are associated with radiological signs of ongoing temporomandibular joint (TMJ) bone tissue resorption and disc displacement in RA patients. Twenty-two consecutive outpatients with TMJ of RA were included. Systemic inflammatory activity was assessed by DAS28. The number of painful regions in the body and ESR, CRP, RF and ACPA were analyzed. TMJ synovial fluid and blood samples were obtained and analyzed for TNF, TNFsRII, IL-1ra, IL-1sRII and ACPA. The ratios between the mediators and their endogenous control receptors were used in the statistical analysis. Magnetic resonance imaging was performed in closed- and open-mouth positions and evaluated regarding disc position and presence of condylar and temporal erosions of the TMJ. A high TNF level in relation to TNFsRII in TMJ synovial fluid correlated to the degree of TMJ condylar erosion. A high IL-1ra level in relation to TNF in TMJ synovial fluid was also correlated to the degree of TMJ condylar erosion. The total degree of TMJ condylar erosion was correlated with the number of painful regions. This study indicates that TNF in TMJ synovial fluid mediates TMJ cartilage and bone tissue resorption in RA. The study also suggests that the degree of endogenous cytokine control is of importance for development of bone tissue destruction.

  17. Glycyrrhizin Protects against Acetaminophen-Induced Acute Liver Injury via Alleviating Tumor Necrosis Factor α–Mediated Apoptosis

    PubMed Central

    Yan, Tingting; Wang, Hong; Zhao, Min; Yagai, Tomoki; Chai, Yingying; Krausz, Kristopher W.; Xie, Cen; Cheng, Xuefang; Zhang, Jun; Che, Yuan; Li, Feiyan; Wu, Yuzheng; Brocker, Chad N.; Gonzalez, Frank J.

    2016-01-01

    Acetaminophen (APAP) overdose is the leading cause of drug-induced acute liver failure in Western countries. Glycyrrhizin (GL), a potent hepatoprotective constituent extracted from the traditional Chinese medicine liquorice, has potential clinical use in treating APAP-induced liver failure. The present study determined the hepatoprotective effects and underlying mechanisms of action of GL and its active metabolite glycyrrhetinic acid (GA). Various administration routes and pharmacokinetics–pharmacodynamics analyses were used to differentiate the effects of GL and GA on APAP toxicity in mice. Mice deficient in cytochrome P450 2E1 enzyme (CYP2E1) or receptor interacting protein 3 (RIPK3) and their relative wild-type littermates were subjected to histologic and biochemical analyses to determine the potential mechanisms. Hepatocyte death mediated by tumor necrosis factor α (TNFα)/caspase was analyzed by use of human liver-derived LO2 cells. The pharmacokinetics–pharmacodynamics analysis using various administration routes revealed that GL but not GA potently attenuated APAP-induced liver injury. The protective effect of GL was found only with intraperitoneal and intravenous administration and not with gastric administration. CYP2E1-mediated metabolic activation and RIPK3-mediated necroptosis were unrelated to GL’s protective effect. However, GL inhibited hepatocyte apoptosis via interference with TNFα-induced apoptotic hepatocyte death. These results demonstrate that GL rapidly attenuates APAP-induced liver injury by directly inhibiting TNFα-induced hepatocyte apoptosis. The protective effect against APAP-induced liver toxicity by GL in mice suggests the therapeutic potential of GL for the treatment of APAP overdose. PMID:26965985

  18. Unmasking of a protective tumor necrosis factor receptor I-mediated signal in the collagen-induced arthritis model.

    PubMed

    Williams-Skipp, Cheryll; Raman, Thiagarajan; Valuck, Robert J; Watkins, Herschel; Palmer, Brent E; Scheinman, Robert I

    2009-02-01

    To examine the relative importance of tumor necrosis factor receptor I (TNFRI) signaling in the hematopoietic tissue compartment in the progression of collagen-induced arthritis (CIA), a model of rheumatoid arthritis (RA). DBA/1 mice were administered a lethal radiation dose and were then rescued with bone marrow derived from either DBA/1 or TNFRI(-/-) mice. CIA was then induced, and disease progression was characterized. Surprisingly, mice with CIA that received TNFRI(-/-) donor marrow developed increased disease severity as compared with control mice with CIA. This could not be attributed to an increased primary response to collagen or to the contribution of a non-DBA genetic background. In mice that received TNFRI(-/-) bone marrow, histologic markers of advanced disease were evident shortly after initiation of the immune response to collagen and long before clinical evidence of disease. Serum TNFalpha was undetectable, whereas serum interleukin-12 p40 levels were increased, at the end point of the study in mice that received TNFRI(-/-) bone marrow. These data raise the intriguing possibility of the existence of an antiinflammatory, TNFRI-mediated circuit in the hematopoietic compartment. This circuit bears a resemblance to the switch in TNFalpha function that has been observed during the resolution of bacterial infections. These data suggest that TNFRI-mediated signals in the radioresistant tissues contribute to disease progression, whereas TNFRI-mediated signals in the radiosensitive tissues can contribute to protection from disease. We thus put forward the hypothesis that the degree of response to TNFalpha blockade in RA is dependent in part on the relative genetic strengths of these 2 pathways.

  19. A Small Molecule Agonist of EphA2 Receptor Tyrosine Kinase Inhibits Tumor Cell Migration In Vitro and Prostate Cancer Metastasis In Vivo

    PubMed Central

    Guo, Hong; Miao, Hui; Tochtrop, Gregory P.; Hsieh, Jer-Tsong; Page, Phillip; Liu, Lili; Lindner, Daniel J.; Acharya, Chayan; MacKerell, Alexander D.; Ficker, Eckhard; Song, Jianxing; Wang, Bingcheng

    2012-01-01

    During tumor progression, EphA2 receptor can gain ligand-independent pro-oncogenic functions due to Akt activation and reduced ephrin-A ligand engagement. The effects can be reversed by ligand stimulation, which triggers the intrinsic tumor suppressive signaling pathways of EphA2 including inhibition of PI3/Akt and Ras/ERK pathways. These observations argue for development of small molecule agonists for EphA2 as potential tumor intervention agents. Through virtual screening and cell-based assays, we report here the identification and characterization of doxazosin as a novel small molecule agonist for EphA2 and EphA4, but not for other Eph receptors tested. NMR studies revealed extensive contacts of doxazosin with EphA2/A4, recapitulating both hydrophobic and electrostatic interactions recently found in the EphA2/ephrin-A1 complex. Clinically used as an α1-adrenoreceptor antagonist (Cardura®) for treating hypertension and benign prostate hyperplasia, doxazosin activated EphA2 independent of α1-adrenoreceptor. Similar to ephrin-A1, doxazosin inhibited Akt and ERK kinase activities in an EphA2-dependent manner. Treatment with doxazosin triggered EphA2 receptor internalization, and suppressed haptotactic and chemotactic migration of prostate cancer, breast cancer, and glioma cells. Moreover, in an orthotopic xenograft model, doxazosin reduced distal metastasis of human prostate cancer cells and prolonged survival in recipient mice. To our knowledge, doxazosin is the first small molecule agonist of a receptor tyrosine kinase that is capable of inhibiting malignant behaviors in vitro and in vivo. PMID:22916121

  20. EphA2 is a Mediator of Vemurafenib Resistance and a Novel Therapeutic Target in Melanoma

    PubMed Central

    Miao, Benchun; Ji, Zhenyu; Tan, Li; Taylor, Michael; Zhang, Jianming; Choi, Hwan Geun; Frederick, Dennie T.; Kumar, Raj; Wargo, Jennifer A.; Flaherty, Keith T.; Gray, Nathanael S.; Tsao, Hensin

    2015-01-01

    BRAF(V600E) is the most common oncogenic lesion in melanoma and results in constitutive activation of the mitogen-activated protein kinase (MAPK) pathway and uncontrolled cell growth. Selective BRAF inhibitors such as vemurafenib have been shown to neutralize oncogenic signaling, restrain cellular growth and improve patient outcome. Although several mechanisms of vemurafenib resistance have been described, directed solutions to overcome these resistance lesions are still lacking. Herein, we found that vemurafenib resistance can be (i) mediated by EphA2- a member of the largest receptor tyrosine kinases (RTK) subfamily erythropoietin-producing hepatocellular (Eph) receptors and (ii) associated with a greater phenotypic dependence on EphA2. Furthermore, we developed a series of first-in-class EphA2 inhibitors and show that these new compounds potently induce apoptosis, suppress viability and abrogate tumorigenic growth of melanoma cells, including those that are resistant to vemurafenib. These results provide proof-of-concept that RTK-guided growth, and therapeutic resistance, can be prospectively defined and selectively targeted. PMID:25542448

  1. Eosinophilic esophagitis, celiac disease, and immunoglobulin E-mediated allergy in a 2-year-old child.

    PubMed

    Sánchez-García, S; Ibáñez, M D; Martinez-Gómez, M J; Escudero, C; Vereda, A; Fernández-Rodríguez, M; Rodríguez del Río, P

    2011-01-01

    Celiac disease, eosinophilic esophagitis, and urticaria are 3 manifestations of food allergy with different pathogenic mechanisms. We report the case of a 2-year-old child with digestive symptoms, slow growth, and severe asthma. The results of skin prick tests were positive to several foods. Endoscopy revealed eosinophilic esophagitis and celiac disease. Treatment consisted of a gluten-free diet and a 1-month course of oral corticosteroids. Endoscopy and biopsy findings were normal at 5 years of age. A gluten-free diet is the basis of treatment of celiac disease, but the role of an elimination diet in eosinophilic esophagitis is not well established. Our patient also developed urticaria when exposed to milk and egg.We present, to our knowledge, the first report of a patient with celiac disease, eosinophilic esophagitis, and immediate-type immunoglobulin E-mediated food allergy.

  2. CD40 dependent exacerbation of immune mediated hepatitis by hepatic CD11b+ Gr-1+ myeloid derived suppressor cells in tumor bearing mice

    PubMed Central

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

    2015-01-01

    Immunosuppressive CD11b+Gr-1+ myeloid-derived suppressor cells (MDSC) accumulate in the livers of tumor-bearing mice. We studied hepatic MDSC in two murine models of immune mediated hepatitis. Unexpectedly, treatment of tumor bearing mice with Concanavalin A or α-Galactosylceramide resulted in increased ALT and AST serum levels in comparison to tumor free mice. Adoptive transfer of hepatic MDSC into naïve mice exacerbated Concanavalin A induced liver damage. Hepatic CD11b+Gr-1+ cells revealed a polarized pro-inflammatory gene signature after Concanavalin A treatment. An interferon gamma- dependent up-regulation of CD40 on hepatic CD11b+Gr-1+ cells along with an up-regulation of CD80, CD86, and CD1d after Concanavalin A treatment was observed. Concanavalin A treatment resulted in a loss of suppressor function by tumor-induced CD11b+Gr-1+ MDSC as well as enhanced reactive oxygen species-mediated hepatotoxicity. CD40 knockdown in hepatic MDSC led to increased arginase activity upon Concanavalin A treatment and lower ALT/AST serum levels. Finally, blockade of arginase activity in Cd40−/− tumor-induced myeloid cells resulted in exacerbation of hepatitis and increased reactive oxygen species production in vivo. Our findings indicate that in a setting of acute hepatitis, tumor-induced hepatic MDSC act as pro-inflammatory immune effector cells capable of killing hepatocytes in a CD40-dependent manner. PMID:25616156

  3. Claudin 1 mediates tumor necrosis factor alpha-induced cell migration in human gastric cancer cells.

    PubMed

    Shiozaki, Atsushi; Shimizu, Hiroki; Ichikawa, Daisuke; Konishi, Hirotaka; Komatsu, Shuhei; Kubota, Takeshi; Fujiwara, Hitoshi; Okamoto, Kazuma; Iitaka, Daisuke; Nakashima, Shingo; Nako, Yoshito; Liu, Mingyao; Otsuji, Eigo

    2014-12-21

    To investigate the role of claudin 1 in the regulation of genes involved in cell migration and tumor necrosis factor alpha (TNF-α)-induced gene expression in human gastric adenocarcinoma cells. Knockdown experiments were conducted with claudin 1 small interfering RNA (siRNA), and the effects on the cell cycle, apoptosis, migration and invasion were analyzed in human gastric adenocarcinoma MKN28 cells. The gene expression profiles of cells were analyzed by microarray and bioinformatics. The knockdown of claudin 1 significantly inhibited cell proliferation, migration and invasion, and increased apoptosis. Microarray analysis identified 245 genes whose expression levels were altered by the knockdown of claudin 1. Pathway analysis showed that the top-ranked molecular and cellular function was the cellular movement related pathway, which involved MMP7, TNF-SF10, TGFBR1, and CCL2. Furthermore, TNF- and nuclear frctor-κB were the top-ranked upstream regulators related to claudin 1. TNF-α treatment increased claudin 1 expression and cell migration in MKN28 cells. Microarray analysis indicated that the depletion of claudin 1 inhibited 80% of the TNF-α-induced mRNA expression changes. Further, TNF-α did not enhance cell migration in the claudin 1 siRNA transfected cells. These results suggest that claudin 1 is an important messenger that regulates TNF-α-induced gene expression and migration in gastric cancer cells. A deeper understanding of these cellular processes may be helpful in establishing new therapeutic strategies for gastric cancer.

  4. Tumor exosome-mediated promotion of adhesion to mesothelial cells in gastric cancer cells

    PubMed Central

    Arita, Tomohiro; Ichikawa, Daisuke; Konishi, Hirotaka; Komatsu, Shuhei; Shiozaki, Atsushi; Ogino, Shinpei; Fujita, Yuji; Hiramoto, Hidekazu; Hamada, Junichi; Shoda, Katsutoshi; Kosuga, Toshiyuki; Fujiwara, Hitoshi; Okamoto, Kazuma; Otsuji, Eigo

    2016-01-01

    Background Peritoneal metastasis consists of a highly complex series of steps, and the details of the underlying molecular mechanism remain largely unclear. In this study, the effects of tumor-derived exosomes (TEX) on the progression of gastric cancers were investigated in peritoneal metastasis. Results TEX were internalized in both mesothelial and gastric cancer cells in a cellular origin non-specific manner. Internalization of TEX into mesothelial cells promoted significant adhesion between mesothelial and gastric cancer cells, and TEX internalization into gastric cancer cells significantly promoted migratory ability, while internalization of mesothelial cell-derived exosomes did not. Expression of adhesion-related molecules, such as fibronectin 1 (FN1) and laminin gamma 1 (LAMC1), were increased in mesothelial cells after internalization of TEX from gastric cancer cell line and malignant pleural effusion. Methods TEX were extracted from cell-conditioned medium by ultracentrifugation. The effects of TEX on the malignant potential of gastric cancer were investigated in adhesion, invasion, and proliferation assays. PCR array as well as western blotting were performed to determine the underlying molecular mechanisms. The molecular changes in mesothelial cell after internalization of TEX derived from malignant pleural effusion were also confirmed. Conclusions TEX may play a critical role in the development of peritoneal metastasis of gastric cancer, which may be partially due to inducing increased expression of adhesion molecules in mesothelial cells. PMID:27487135

  5. Tumor exosome-mediated promotion of adhesion to mesothelial cells in gastric cancer cells.

    PubMed

    Arita, Tomohiro; Ichikawa, Daisuke; Konishi, Hirotaka; Komatsu, Shuhei; Shiozaki, Atsushi; Ogino, Shinpei; Fujita, Yuji; Hiramoto, Hidekazu; Hamada, Junichi; Shoda, Katsutoshi; Kosuga, Toshiyuki; Fujiwara, Hitoshi; Okamoto, Kazuma; Otsuji, Eigo

    2016-08-30

    Peritoneal metastasis consists of a highly complex series of steps, and the details of the underlying molecular mechanism remain largely unclear. In this study, the effects of tumor-derived exosomes (TEX) on the progression of gastric cancers were investigated in peritoneal metastasis. TEX were internalized in both mesothelial and gastric cancer cells in a cellular origin non-specific manner. Internalization of TEX into mesothelial cells promoted significant adhesion between mesothelial and gastric cancer cells, and TEX internalization into gastric cancer cells significantly promoted migratory ability, while internalization of mesothelial cell-derived exosomes did not. Expression of adhesion-related molecules, such as fibronectin 1 (FN1) and laminin gamma 1 (LAMC1), were increased in mesothelial cells after internalization of TEX from gastric cancer cell line and malignant pleural effusion. TEX were extracted from cell-conditioned medium by ultracentrifugation. The effects of TEX on the malignant potential of gastric cancer were investigated in adhesion, invasion, and proliferation assays. PCR array as well as western blotting were performed to determine the underlying molecular mechanisms. The molecular changes in mesothelial cell after internalization of TEX derived from malignant pleural effusion were also confirmed. TEX may play a critical role in the development of peritoneal metastasis of gastric cancer, which may be partially due to inducing increased expression of adhesion molecules in mesothelial cells.

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

    SciTech Connect

    Kurayoshi, Kenta; Ozono, Eiko; Iwanaga, Ritsuko

    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 (suicidemore » 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

  7. Soy Protein Isolate Protects Against Ethanol-Mediated Tumor Progression in Diethylnitrosamine-Treated Male Mice.

    PubMed

    Mercer, Kelly E; Pulliam, Casey; Hennings, Leah; Lai, Keith; Cleves, Mario; Jones, Ellen; Drake, Richard R; Ronis, Martin

    2016-06-01

    In this study, diethylnitrosamine-treated male mice were assigned to three groups: (i) a 35% high fat ethanol liquid diet (EtOH) with casein as the protein source, (ii) the same EtOH liquid diet with soy protein isolate as the sole protein source (EtOH/SPI), (iii) and a chow group. EtOH feeding continued for 16 weeks. As expected, EtOH increased the incidence and multiplicity of basophilic lesions and adenomas compared with the chow group, P < 0.05. Soy protein replacement of casein in the EtOH diet significantly reduced adenoma progression when compared with the EtOH and EtOH/SPI group (P < 0.05). Tumor reduction in the EtOH/SPI group corresponded to reduced liver injury associated with decreased hepatic Tnfα and Cd14 antigen (Cd14) expression and decreased nuclear accumulation of NF-κB1 protein compared with the EtOH group (P < 0.05). Detection of sphingolipids using high-resolution matrix-assisted laser desorption/ionization-Fourier transform ion cyclotron resonance (MALDI-FTICR) imaging mass spectrometry revealed increased accumulation of long acyl chain ceramide species, and sphingosine-1-phosphate (S1P) in the EtOH group that were significantly reduced in the EtOH/SPI group. Chronic EtOH feeding also increased mRNA expression of β-catenin transcriptional targets, including cyclin D1 (Ccnd1), matrix metallopeptidase 7 (Mmp7), and glutamine synthetase (Glns), which were reduced in the EtOH/SPI group (P < 0.05). We conclude that soy prevents tumorigenesis by reducing proinflammatory and oxidative environment resulting from EtOH-induced hepatic injury, and by reducing hepatocyte proliferation through inhibition of β-catenin signaling. These mechanisms may involve changes in sphingolipid signaling. Cancer Prev Res; 9(6); 466-75. ©2016 AACR. ©2016 American Association for Cancer Research.

  8. Jagged mediates differences in normal and tumor angiogenesis by affecting tip-stalk fate decision

    PubMed Central

    Boareto, Marcelo; Jolly, Mohit Kumar; Ben-Jacob, Eshel; Onuchic, José N.

    2015-01-01

    Angiogenesis is critical during development, wound repair, and cancer progression. During angiogenesis, some endothelial cells adopt a tip phenotype to lead the formation of new branching vessels; the trailing stalk cells proliferate to develop the vessel. Notch and VEGF signaling mediate the selection of these tip endothelial cells. However, how Jagged, a Notch ligand that is overexpressed in cancer, affects angiogenesis remains elusive. Here, by developing a theoretical framework for Notch-Delta-Jagged-VEGF signaling, we found that higher production levels of Jagged destabilizes the tip and stalk cell fates and can give rise to a hybrid tip/stalk phenotype that leads to poorly perfused and chaotic angiogenesis, which is a hallmark of cancer. Consistently, the signaling interactions that restrict Notch-Jagged signaling, such as Fringe, cis-inhibition, and increased production of Delta, stabilize tip and stalk fates and limit the existence of hybrid tip/stalk phenotype. Our results underline how overexpression of Jagged can transform physiological angiogenesis into pathological one. PMID:26153421

  9. Tumor Necrosis Factor-Mediated Survival of CD169+ Cells Promotes Immune Activation during Vesicular Stomatitis Virus Infection

    PubMed Central

    2017-01-01

    ABSTRACT Innate immune activation is essential to mount an effective antiviral response and to prime adaptive immunity. Although a crucial role of CD169+ cells during vesicular stomatitis virus (VSV) infections is increasingly recognized, factors regulating CD169+ cells during viral infections remain unclear. Here, we show that tumor necrosis factor is produced by CD11b+ Ly6C+ Ly6G+ cells following infection with VSV. The absence of TNF or TNF receptor 1 (TNFR1) resulted in reduced numbers of CD169+ cells and in reduced type I interferon (IFN-I) production during VSV infection, with a severe disease outcome. Specifically, TNF triggered RelA translocation into the nuclei of CD169+ cells; this translocation was inhibited when the paracaspase MALT-1 was absent. Consequently, MALT1 deficiency resulted in reduced VSV replication, defective innate immune activation, and development of severe disease. These findings indicate that TNF mediates the maintenance of CD169+ cells and innate and adaptive immune activation during VSV infection. IMPORTANCE Over the last decade, strategically placed CD169+ metallophilic macrophages in the marginal zone of the murine spleen and lymph nodes (LN) have been shown to play a very important role in host defense against viral pathogens. CD169+ macrophages have been shown to activate innate and adaptive immunity via “enforced virus replication,” a controlled amplification of virus particles. However, the factors regulating the CD169+ macrophages remain to be studied. In this paper, we show that after vesicular stomatitis virus infection, phagocytes produce tumor necrosis factor (TNF), which signals via TNFR1, and promote enforced virus replication in CD169+ macrophages. Consequently, lack of TNF or TNFR1 resulted in defective immune activation and VSV clearance. PMID:29142134

  10. SV40 Infection of Mesenchymal Stromal Cells From Wharton's Jelly Drives the Production of Inflammatory and Tumoral Mediators.

    PubMed

    Cason, Carolina; Campisciano, Giuseppina; Zanotta, Nunzia; Valencic, Erica; Delbue, Serena; Bella, Ramona; Comar, Manola

    2017-11-01

    The Mesenchymal Stromal Cells from umbilical cord Wharton's jelly (WJSCs) are a source of cells with high potentiality for the treatment of human immunological disorders. Footprints of the oncogenic viruses Simian Virus 40 (SV40) and JC Virus (JCPyV) have been recently detected in human WJSCs specimens. The aim of this study is to evaluate if WJSCs can be efficiently infected by these Polyomaviruses and if they can potentially exert tumoral activity. Cell culture experiments indicated that WJSCs could sustain both SV40 and JCPyV infections. A transient and lytic replication was observed for JCPyV, while SV40 persistently infected WJSCs over a long period of time, releasing a viral progeny at low titer without evident cytopathic effect (CPE). Considering the association between SV40 and human tumors and the reported ability of the oncogenic viruses to drive the host innate immune response to cell transformation, the expression profile of a large panel of immune mediators was evaluated in supernatants by the Bioplex platform. RANTES, IL-3, MIG, and IL-12p40, involved in chronic inflammation, cells differentiation, and transformation, were constantly measured at high concentration comparing to control. These findings represent a new aspect of SV40 biological activity in the humans, highlighting its interaction with specific host cellular pathways. In view of these results, it seems to be increasingly urgent to consider Polyomaviruses in the management of WJSCs for their safely use as promising therapeutic source. J. Cell. Physiol. 232: 3060-3066, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

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

    SciTech Connect

    Zhuo, Baobiao; Li, Yuan; Li, Zhengwei

    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 proliferationmore » 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.« less

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

    PubMed Central

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

    2013-01-01

    Background Snail is an important transcription factor implicated in several tumor progression and can be induced by reactive oxygen species (ROS). Areca quid chewing is a major risk factor of oral squamous cell carcinoma (OSCC). Therefore, we hypothesize that the major areca nut alkaloid arecoline may induce Snail via ROS and involve in the pathogenesis of areca quid chewing-associated OSCC. Methodology/Principal Finding Thirty-six OSCC and ten normal oral epithelium specimens were examined by immunohistochemistry and analyzed by the clinico-pathological profiles. Cytotoxicity, 2′, 7′-dichlorofluorescein diacetate assay, and western blot were used to investigate the effects of arecoline in human oral keratinocytes (HOKs) and oral epithelial cell line OECM-1 cells. In addition, antioxidants N-acetyl-L-cysteine (NAC), curcumin, and epigallocatechin-3 gallate (EGCG) were added to find the possible regulatory mechanisms. Initially, Snail expression was significantly higher in OSCC specimens (p<0.05). Elevated Snail expression was associated with lymph node metastasis (p = 0.031) and poor differentiation (p = 0.017). Arecoline enhanced the generation of intracellular ROS at the concentration higher than 40 µg/ml (p<0.05). Arecoline was also found to induced Snail expression in a dose- and time-dependent manner (p<0.05). Treatment with NAC, curcumin, and EGCG markedly inhibited arecoline induced Snail expression (p<0.05). Conclusion/Significance: Our results suggest that Snail overexpression in areca quid chewing-associated OSCC is associated with tumors differentiation and lymph node metastasis. Arecoline-upregulated Snail expression may be mediated by ROS generation. In addition, arecoline induced Snail expression was downregulated by NAC, curcumin, and EGCG. PMID:23874481

  13. Tumor Necrosis Factor-Mediated Survival of CD169+ Cells Promotes Immune Activation during Vesicular Stomatitis Virus Infection.

    PubMed

    Shinde, Prashant V; Xu, Haifeng C; Maney, Sathish Kumar; Kloetgen, Andreas; Namineni, Sukumar; Zhuang, Yuan; Honke, Nadine; Shaabani, Namir; Bellora, Nicolas; Doerrenberg, Mareike; Trilling, Mirko; Pozdeev, Vitaly I; van Rooijen, Nico; Scheu, Stefanie; Pfeffer, Klaus; Crocker, Paul R; Tanaka, Masato; Duggimpudi, Sujitha; Knolle, Percy; Heikenwalder, Mathias; Ruland, Jürgen; Mak, Tak W; Brenner, Dirk; Pandyra, Aleksandra A; Hoell, Jessica I; Borkhardt, Arndt; Häussinger, Dieter; Lang, Karl S; Lang, Philipp A

    2018-02-01

    Innate immune activation is essential to mount an effective antiviral response and to prime adaptive immunity. Although a crucial role of CD169 + cells during vesicular stomatitis virus (VSV) infections is increasingly recognized, factors regulating CD169 + cells during viral infections remain unclear. Here, we show that tumor necrosis factor is produced by CD11b + Ly6C + Ly6G + cells following infection with VSV. The absence of TNF or TNF receptor 1 (TNFR1) resulted in reduced numbers of CD169 + cells and in reduced type I interferon (IFN-I) production during VSV infection, with a severe disease outcome. Specifically, TNF triggered RelA translocation into the nuclei of CD169 + cells; this translocation was inhibited when the paracaspase MALT-1 was absent. Consequently, MALT1 deficiency resulted in reduced VSV replication, defective innate immune activation, and development of severe disease. These findings indicate that TNF mediates the maintenance of CD169 + cells and innate and adaptive immune activation during VSV infection. IMPORTANCE Over the last decade, strategically placed CD169 + metallophilic macrophages in the marginal zone of the murine spleen and lymph nodes (LN) have been shown to play a very important role in host defense against viral pathogens. CD169 + macrophages have been shown to activate innate and adaptive immunity via "enforced virus replication," a controlled amplification of virus particles. However, the factors regulating the CD169 + macrophages remain to be studied. In this paper, we show that after vesicular stomatitis virus infection, phagocytes produce tumor necrosis factor (TNF), which signals via TNFR1, and promote enforced virus replication in CD169 + macrophages. Consequently, lack of TNF or TNFR1 resulted in defective immune activation and VSV clearance. Copyright © 2018 Shinde et al.

  14. The proinflammatory mediator Platelet Activating Factor is an effective substrate for human group X secreted phospholipase A2.

    PubMed

    Gora, Sarah; Lambeau, Gerard; Bollinger, James G; Gelb, Michael; Ninio, Ewa; Karabina, Sonia-Athina

    2006-09-01

    Platelet Activating Factor (PAF) is a potent mediator of inflammation whose biological activity depends on the acetyl group esterified at the sn-2 position of the molecule. PAF-acetylhydrolase (PAF-AH), a secreted calcium-independent phospholipase A(2), is known to inactivate PAF by formation of lyso-PAF and acetate. However, PAF-AH deficient patients are not susceptible to the biological effects of inhaled PAF in airway inflammation, suggesting that other enzymes may regulate extracellular levels of PAF. We therefore examined the hydrolytic activity of the recently described human group X secreted phospholipase A(2) (hGX sPLA(2)) towards PAF. Among different sPLA(2)s, hGX sPLA(2) has the highest affinity towards phosphatidylcholine (PC), the major phospholipid of cellular membranes and plasma lipoproteins. Our results show that unlike group IIA, group V, and the pancreatic group IB sPLA(2), recombinant hGX sPLA(2) can efficiently hydrolyze PAF. The hydrolysis of PAF by hGX sPLA(2) rises abruptly when the concentration of PAF passes through its critical micelle concentration suggesting that the enzyme undergoes interfacial binding and activation to PAF. In conclusion, our study shows that hGX sPLA(2) may be a novel player in PAF regulation during inflammatory processes.

  15. Nano-graphene oxide-mediated In vivo fluorescence imaging and bimodal photodynamic and photothermal destruction of tumors.

    PubMed

    Kalluru, Poliraju; Vankayala, Raviraj; Chiang, Chi-Shiun; Hwang, Kuo Chu

    2016-07-01

    Cancer is one of the major life-threatening diseases among human beings. Developing a simple, cost-effective and biocompatible approach to treat cancers using ultra-low doses of light is a grand challenge in clinical cancer treatments. In this study, we report for the first time that nano-sized graphene oxide (GO) exhibits single-photon excitation wavelength dependent photoluminescence in the visible and short near-infrared (NIR) region, suitable for in vivo multi-color fluorescence imaging. We also demonstrate in both in vitro and in vivo experiments to show that nano GO can sensitize the formation of singlet oxygen to exert combined nanomaterial-mediated photodynamic therapeutic (NmPDT) and photothermal therapy (NmPTT) effects on the destruction of B16F0 melanoma tumors in mice using ultra-low doses (∼0.36 W/cm(2)) of NIR (980 nm) light. The average half-life span of the mice treated by the GO-PEG-folate-mediated NmPDT effects is beyond 30 days, which is ∼1.8 times longer than the mice treated with doxorubicin (17 days). Overall, the current study points out a successful example of using GO-PEG-folate nanocomposite as a theranostic nanomedicine to exert simultaneously in vivo fluorescent imaging as well as combined NmPDT and NmPTT effects for clinical cancer treatments. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

    PubMed

    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. © 2014 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

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

    SciTech Connect

    Zhu, Xinghua; Miao, Xiaobing; Wu, Yaxun

    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 anmore » 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.« less

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

    SciTech Connect

    Aravindan, Natarajan, E-mail: naravind@ouhsc.edu; Aravindan, Sheeja; Pandian, Vijayabaskar

    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 cellsmore » 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.« less

  19. Styrene respiratory tract toxicity and mouse lung tumors are mediated by CYP2F-generated metabolites.

    PubMed

    Cruzan, George; Carlson, Gary P; Johnson, Keith A; Andrews, Larry S; Banton, Marcy I; Bevan, Christopher; Cushman, Janette R

    2002-06-01

    Mice are particularly sensitive to respiratory tract toxicity following styrene exposure. Inhalation of styrene by mice results in cytotoxicity in terminal bronchioles, followed by increased incidence of bronchioloalveolar tumors, as well as degeneration and atrophy of nasal olfactory epithelium. In rats, no effects on terminal bronchioles are seen, but effects in the nasal olfactory epithelium do occur, although to a lesser degree and from higher exposure concentrations. In addition, cytotoxicity and tumor formation are not related to blood levels of styrene or styrene oxide (SO) as measured in chronic studies. Whole-body metabolism studies have indicated major differences in styrene metabolism between rats and mice. The major differences are 4- to 10-fold more ring-oxidation and phenylacetaldehyde pathways in mice compared to rats. The data indicate that local metabolism of styrene is responsible for cytotoxicity in the respiratory tract. Cytotoxicity is seen in tissues that are high in CYP2F P450 isoforms. These tissues have been demonstrated to produce a high ratio of R-SO compared to S-SO (at least 2.4 : 1). In other rat tissues the ratio is less than 1, while in mouse liver the ratio is about 1.1. Inhibition of CYP2F with 5-phenyl-1-pentyne prevents the styrene-induced cytotoxicity in mouse terminal bronchioles and nasal olfactory epithelium. R-SO has been shown to be more toxic to mouse terminal bronchioles than S-SO. In addition, 4-vinylphenol (ring oxidation of styrene) has been shown to be highly toxic to mouse terminal bronchioles and is also metabolized by CYP2F. In human nasal and lung tissues, styrene metabolism to SO is below the limit of detection in nearly all samples, and the most active sample of lung was approximately 100-fold less active than mouse lung tissue. We conclude that styrene respiratory tract toxicity in mice and rats, including mouse lung tumors, are mediated by CYP2F-generated metabolites. The PBPK model predicts that humans do not

  20. Group X Phospholipase A2 Stimulates the Proliferation of Colon Cancer Cells by Producing Various Lipid Mediators

    PubMed Central

    Surrel, Fanny; Jemel, Ikram; Boilard, Eric; Bollinger, James G.; Payré, Christine; Mounier, Carine M.; Talvinen, Kati A.; Laine, Veli J. O.; Nevalainen, Timo J.; Gelb, Michael H.

    2009-01-01

    Among mammalian secreted phospholipases A2 (sPLA2s), the group X enzyme has the most potent hydrolyzing capacity toward phosphatidylcholine, the major phospholipid of cell membrane and lipoproteins. This enzyme has recently been implicated in chronic inflammatory diseases such as atherosclerosis and asthma and may also play a role in colon tumorigenesis. We show here that group X sPLA2 [mouse (m)GX] is one of the most highly expressed PLA2 in the mouse colon and that recombinant mouse and human enzymes stimulate proliferation and mitogen-activated protein kinase activation of various colon cell lines, including Colon-26 cancer cells. Among various recombinant sPLA2s, mGX is the most potent enzyme to stimulate cell proliferation. Based on the use of sPLA2 inhibitors, catalytic site mutants, and small interfering RNA silencing of cytosolic PLA2α and M-type sPLA2 receptor, we demonstrate that mGX promotes cell proliferation independently of the receptor and via its intrinsic catalytic activity and production of free arachidonic acid and lysophospholipids, which are mitogenic by themselves. mGX can also elicit the production of large amounts of prostaglandin E2 and other eicosanoids from Colon-26 cells, but these lipid mediators do not play a role in mGX-induced cell proliferation because inhibitors of cyclooxygenases and lipoxygenases do not prevent sPLA2 mitogenic effects. Together, our results indicate that group X sPLA2 may play an important role in colon tumorigenesis by promoting cancer cell proliferation and releasing various lipid mediators involved in other key events in cancer progression. PMID:19602573

  1. Group X phospholipase A2 stimulates the proliferation of colon cancer cells by producing various lipid mediators.

    PubMed

    Surrel, Fanny; Jemel, Ikram; Boilard, Eric; Bollinger, James G; Payré, Christine; Mounier, Carine M; Talvinen, Kati A; Laine, Veli J O; Nevalainen, Timo J; Gelb, Michael H; Lambeau, Gérard

    2009-10-01

    Among mammalian secreted phospholipases A2 (sPLA(2)s), the group X enzyme has the most potent hydrolyzing capacity toward phosphatidylcholine, the major phospholipid of cell membrane and lipoproteins. This enzyme has recently been implicated in chronic inflammatory diseases such as atherosclerosis and asthma and may also play a role in colon tumorigenesis. We show here that group X sPLA(2) [mouse (m)GX] is one of the most highly expressed PLA(2) in the mouse colon and that recombinant mouse and human enzymes stimulate proliferation and mitogen-activated protein kinase activation of various colon cell lines, including Colon-26 cancer cells. Among various recombinant sPLA(2)s, mGX is the most potent enzyme to stimulate cell proliferation. Based on the use of sPLA(2) inhibitors, catalytic site mutants, and small interfering RNA silencing of cytosolic PLA(2)alpha and M-type sPLA(2) receptor, we demonstrate that mGX promotes cell proliferation independently of the receptor and via its intrinsic catalytic activity and production of free arachidonic acid and lysophospholipids, which are mitogenic by themselves. mGX can also elicit the production of large amounts of prostaglandin E2 and other eicosanoids from Colon-26 cells, but these lipid mediators do not play a role in mGX-induced cell proliferation because inhibitors of cyclooxygenases and lipoxygenases do not prevent sPLA(2) mitogenic effects. Together, our results indicate that group X sPLA(2) may play an important role in colon tumorigenesis by promoting cancer cell proliferation and releasing various lipid mediators involved in other key events in cancer progression.

  2. The phzA2-G2 Transcript Exhibits Direct RsmA-Mediated Activation in Pseudomonas aeruginosa M18

    PubMed Central

    Ren, Bin; Shen, Huifeng; Lu, Zhi John; Liu, Haiming; Xu, Yuquan

    2014-01-01

    In bacteria, RNA-binding proteins of the RsmA/CsrA family act as post-transcriptional regulators that modulate translation initiation at target transcripts. The Pseudomonas aeruginosa genome contains two phenazine biosynthetic (phz) gene clusters, phzA1-G1 (phz1) and phzA2-G2 (phz2), each of which is responsible for phenazine-1-carboxylic acid (PCA) biosynthesis. In the present study, we show that RsmA exhibits differential gene regulation on two phz clusters in P. aeruginosa M18 at the post-transcriptional level. Based on the sequence analysis, four GGA motifs, the potential RsmA binding sites, are found on the 5′-untranslated region (UTR) of the phz2 transcript. Studies with a series of lacZ reporter fusions, and gel mobility shift assays suggest that the third GGA motif (S3), located 21 nucleotides upstream of the Shine-Dalgarno (SD) sequence, is involved in direct RsmA-mediated activation of phz2 expression. We therefore propose a novel model in which the binding of RsmA to the target S3 results in the destabilization of the stem-loop structure and the enhancement of ribosome access. This model could be fully supported by RNA structure prediction, free energy calculations, and nucleotide replacement studies. In contrast, various RsmA-mediated translation repression mechanisms have been identified in which RsmA binds near the SD sequence of target transcripts, thereby blocking ribosome access. Similarly, RsmA is shown to negatively regulate phz1 expression. Our new findings suggest that the differential regulation exerted by RsmA on the two phz clusters may confer an advantage to P. aeruginosa over other pseudomonads containing only a single phz cluster in their genomes. PMID:24586939

  3. P2X7 Integrates PI3K/AKT and AMPK-PRAS40-mTOR Signaling Pathways to Mediate Tumor Cell Death

    PubMed Central

    Bai, Aiping; Zhang, Chunqing; Li, Linglin; Enjyoji, Keiichi; Junger, Wolfgang G.; Robson, Simon C.; Wu, Yan

    2013-01-01

    Background Extracellular adenosine triphosphate (ATP) functions as a novel danger signal that boosts antitumor immunity and can also directly kill tumor cells. We have previously reported that chronic exposure of tumor cells to ATP provokes P2X7-mediated tumor cell death, by as yet incompletely defined molecular mechanisms. Methodology/Principal Findings Here, we show that acute exposure of tumor cells to ATP results in rapid cytotoxic effects impacting several aspects of cell growth/survival, leading to inhibition of tumor growth in vitro and in vivo. Using agonist and antagonist studies together with generation of P2X7 deficient tumor cell lines by lentiviral shRNA delivery system, we confirm P2X7 to be the central control node transmitting extracellular ATP signals. We identify that downstream intracellular signaling regulatory networks implicate two signaling pathways: the known P2X7-PI3K/AKT axis and remarkably a novel P2X7-AMPK-PRAS40-mTOR axis. When exposed to high levels of extracellular ATP, these two signaling axes perturb the balance between growth and autophagy, thereby promoting tumor cell death. Conclusions Our study defines novel molecular mechanisms underpinning the antitumor actions of P2X7 and provides a further rationale for purine-based drugs in targeted cancer therapy. PMID:23565201

  4. Adenoviruses-mediated RNA interference targeting cytosolic phospholipase A2α attenuates focal ischemic brain damage in mice.

    PubMed

    Wu, Huijun; Liu, Hui; Zuo, Fengtong; Zhang, Lihua

    2018-04-01

    Cerebral ischemia injury is a clinical, frequently occurring disease, which causes a heavy burden on society and families. It has been demonstrated that cytosolic phospholipase A2α (cPLA2α) is significant in neurological injury caused by ischemic brain injury, and inhibition of cPLA2α may reduce stroke injury. In the present study, the role of cPLA2α was investigated in a mouse model of middle cerebral artery occlusion and/or reperfusion (MCAO/R) using an effective cPLA2α inhibitor and adenoviruses‑mediated RNA interference. The most effective recombinant adenovirus encoding cPLA2α small interfering RNA (pAd‑siRNA‑cPLA2α) was constructed and selected. MCAO/R surgery is used to construct the model of focal ischemic brain damage in mice. Adenoviruses‑mediated RNA interference targeting cPLA2α was administered by stereotactic surgery 2 h before the MCAO/R. The expression/activity of cPLA2α and cPLA2α‑derived injurious lipid mediators was assessed. pAd‑siRNA‑cPLA2α‑treated animals (RNA interference; RNAi group) were compared with pAd-siRNA-control-treated animals (negative group) with regard to neurological deficit, motor function, pathological changes, apoptosis, and infarct volume. The RNAi group animals reduced the expression level of cPLA2α, as determined by western blotting and reverse transcription‑quantitative polymerase chain reaction, the improvement of locomotor function was evaluated by rotarod test, and the decrease of apoptosis was evaluated by terminal deoxynucleotidyl transferase dUTP nick end‑labeling staining. The decreased infarct areas were evaluated by 2,3,5‑triphenyltetrazolium chloride staining. The expression levels of prostaglandin E2, leukotrienes B4, lysophosphatidylcholine and free fatty acids were reduced in the RNAi group when compared with the negative control group. Thus, the data indicates that the expression level of cPLA2α was effectively controlled by pAd‑siRNA‑cPLA2α treatment. p

  5. GITR engagement in combination with CTLA-4 blockade completely abrogates immunosuppression mediated by human liver tumor-derived regulatory T cells ex vivo.

    PubMed

    Pedroza-Gonzalez, Alexander; Zhou, Guoying; Singh, Simar Pal; Boor, Patrick Pc; Pan, Qiuwei; Grunhagen, Dirk; de Jonge, Jeroen; Tran, Tc Khe; Verhoef, Cornelis; IJzermans, Jan Nm; Janssen, Harry LA; Biermann, Katharina; Kwekkeboom, Jaap; Sprengers, Dave

    2015-12-01

    In liver cancer tumor-infiltrating regulatory T cells (Ti-Treg) are potent suppressors of tumor-specific T-cell responses and express high levels of the Treg-associated molecules cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) and glucocorticoid-induced tumor necrosis factor receptor (GITR). In this study, we have evaluated the capacity of GITR-ligation, CTLA-4-blockade and a combination of both treatments to alleviate immunosuppression mediated by Ti-Treg. Using ex vivo isolated cells from individuals with hepatocellular carcinoma (HCC) or liver metastases from colorectal cancer (LM-CRC) we show that treatment with a soluble form of the natural ligand of GITR (GITRL), or with blocking antibodies to CTLA-4, reduces the suppression mediated by human liver tumor-infiltrating CD4 + Foxp3+ Treg, thereby restoring proliferation and cytokine production by effector T cells. Importantly, combined treatment with low doses of both molecules exhibited stronger recovery of T cell function compared with either treatment alone. Our data suggest that in patients with primary and secondary liver cancer both GITR-ligation and anti-CTLA-4 mAb can improve the antitumor immunity by abrogating Ti-Treg mediated suppression.

  6. Development and optimization of a tumor targeting system based on microbial synthesized PHA biopolymers and PhaP mediated functional modification.

    PubMed

    Fan, Fan; Wang, Leilei; Ouyang, Zhenlin; Wen, Yurong; Lu, Xiaoyun

    2018-04-01

    Polyhydroxyalkanoate (PHA) is a class of microbial synthesized biodegradable and biocompatible aliphatic polymer which has been developed into nanoparticles (NPs) for sustained release of hydrophobic compounds. Taking advantage of the natural PHA binding protein PhaP which could be steadily adsorbed onto PHA NPs through hydrophobic interaction, a tumor targeting system was developed in this study by presenting an epidermal growth factor receptor (EGFR)-targeting peptide (ETP) on the surface of PHA NPs, via PhaP mediated adsorption. To reveal the effects of residual emulsifiers on PhaP mediated ETP modification and optimize the tumor targeting capacity of the system, a novel emulsifier-free PHA NPs (EF-NPs) was fabricated together with other two kinds of conventional emulsifier-required PHA NPs (PVA-NPs and P68-NPs, which were prepared with poly(vinyl alcohol) (PVA) and Pluronic F68 as emulsifiers, respectively). By analyzing the surface hydrophobicity, the amount of adsorbed fusion protein, and the cellular uptake of all kinds of PHA NPs, our results demonstrated that EF-NPs with stronger surface hydrophobicity were the most proper formulation for further PhaP mediated ETP functionalization. The residual PVA and Pluronic F68 affected the modification efficiency and secondary structure of ETP-PhaP fusion protein, and finally obstructed the targeting effect of ETP-PhaP modified PVA-NPs and P68-NPs to EGFR over-expressed tumor cells. The animal experiment further confirmed the effectiveness and feasibility of in vivo application of ETP-PhaP functionalized EF-NPs, indicating that it could be served as a promising tumor targeting system with satisfactory EGFR targeting ability. This PhaP mediated bio-modification process also opens a wide way for developing various PHA-based targeting systems by presenting different tumor or other tissue-specific targeting peptides.

  7. Folate Receptor-Mediated Enhanced and Specific Delivery of Far-Red Light-Activatable Prodrugs of Combretastatin A-4 to FR-Positive Tumor

    PubMed Central

    2015-01-01

    We examined the concept of a novel prodrug strategy in which anticancer drug can be locally released by visible/near IR light, taking advantage of the photodynamic process and photo-unclick chemistry. Our most recently formulated prodrug of combretastatin A-4, Pc-(L-CA4)2, showed multifunctionality for fluorescence imaging, light-activated drug release, and the combined effects of PDT and local chemotherapy. In this formulation, L is a singlet oxygen cleavable linker. Here, we advanced this multifunctional prodrug by adding a tumor-targeting group, folic acid (FA). We designed and prepared four FA-conjugated prodrugs 1–4 (CA4-L-Pc-PEGn-FA: n = 0, 2, 18, ∼45) and one non-FA-conjugated prodrug 5 (CA4-L-Pc-PEG18-boc). Prodrugs 3 and 4 had a longer PEG spacer and showed higher hydrophilicity, enhanced uptake to colon 26 cells via FR-mediated mechanisms, and more specific localization to SC colon 26 tumors in Balb/c mice than prodrugs 1 and 2. Prodrug 4 also showed higher and more specific uptake to tumors, resulting in selective tumor damage and more effective antitumor efficacy than non-FA-conjugated prodrug 5. FR-mediated targeting seemed to be an effective strategy to spare normal tissues surrounding tumors in the illuminated area during treatment with this prodrug. PMID:25351441

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

    PubMed

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

    2014-12-17

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

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

    PubMed Central

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

    1991-01-01

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

  10. Macrophages promote coal tar pitch extract-induced tumorigenesis of BEAS-2B cells and tumor metastasis in nude mice mediated by AP-1.

    PubMed

    Zhang, Peng; Jin, Yue-Fei; Zhang, Qiao; Wu, Yi-Ming; Wu, Wei-Dong; Yao, Wu; Wu, Yong-Jun; Li, Zhi-Tao; Zhao, Yong; Liu, Yu; Feng, Fei-Fei

    2014-01-01

    We sought to evaluate the role of tumor associated macrophages (TAMs) on the promotion of coal tar pitch extract (CTPE)-induced tumorigenesis of human bronchial epithelial cells (BEAS-2B) and tumor metastasis in nude mice, and related mechanisms. BEAS-2B cells were first treated with 2.4 mg/mL CTPE for 72 hours. After removal of CTPE, the cells were continuously cultured and passaged using trypsin-EDTA. THP-1 cells were used as macrophage-like cells. BEAS-2B cells under different conditions (n=6/ group) were injected into the back necks of nude mice, and alterations of tumor xenograft growth, indicative of tumorigenicity, and tumor metastasis were determined. Pathological changes (tumor nests and microvascular lesions) of HE-stained tumor tissues were also evaluated. The expression of AP-1(c-Jun) in xenografts and metastatic tumors was determined using immunohistochemistry. Tumor size and weight in nude mice transplanted with the mixture of CTPE-induced passage 30 BEAS-2B and THP-1 cells (2:1) were increased compared to those from the CTPE-treated BEAS-2B cells at passage 30 alone at different observation time points. Tumor metastasis to lymph nodes and liver was only detected after transplantation of a mixture the two kinds of cells. The numbers of tumor nests and microvascular lesions, and the expression levels of AP-1 (c-Jun) in tumors from the mixture of two kinds of cells were increased apparently in contrast to those in tumor from the CTPE-treated BEAS-2B cells of passage 30 alone. In addition, there was positive correlation between AP-1 (c-Jun) expression level and the number of microvascular lesions, or between AP-1 (c-Jun) expression level and tumor metastasis in these two groups. TAMs not only facilitate tumorigenesis transformation of CTPE-induced BEAS-2B cells, but also promote tumor growth, angiogenesis and metastasis in nude mice in vivo, which may be mediated by AP-1.

  11. Spatial organization of Hippo signaling at the plasma membrane mediated by the tumor suppressor Merlin/NF2.

    PubMed

    Yin, Feng; Yu, Jianzhong; Zheng, Yonggang; Chen, Qian; Zhang, Nailing; Pan, Duojia

    2013-09-12

    Although Merlin/NF2 was discovered two decades ago as a tumor suppressor underlying Neurofibromatosis type II, its precise molecular mechanism remains poorly understood. Recent studies in Drosophila revealed a potential link between Merlin and the Hippo pathway by placing Merlin genetically upstream of the kinase Hpo/Mst. In contrast to the commonly depicted linear model of Merlin functioning through Hpo/Mst, here we show that in both Drosophila and mammals, Merlin promotes downstream Hippo signaling without activating the intrinsic kinase activity of Hpo/Mst. Instead, Merlin directly binds and recruits the effector kinase Wts/Lats to the plasma membrane. Membrane recruitment, in turn, promotes Wts phosphorylation by the Hpo-Sav kinase complex. We further show that disruption of the actin cytoskeleton promotes Merlin-Wts interactions, which implicates Merlin in actin-mediated regulation of Hippo signaling. Our findings elucidate an important molecular function of Merlin and highlight the plasma membrane as a critical subcellular compartment for Hippo signal transduction. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. Allicin sensitizes hepatocellular cancer cells to anti-tumor activity of 5-fluorouracil through ROS-mediated mitochondrial pathway.

    PubMed

    Zou, Xuejing; Liang, Jiyun; Sun, Jingyuan; Hu, Xiaoyun; Lei, Ling; Wu, Dehua; Liu, Li

    2016-08-01

    Drug resistance and hepatic dysfunction are the two major factors that limit the application of chemotherapy for hepatocellular carcinoma (HCC). It has been reported that allicin has the hepatic protective effect and antitumor activity. Hence allicin may be an ideal enhancer to chemotherapy regimen of HCC. In the present study, we demonstrated that allicin enhanced 5-fluorouracil (5-FU) inducing cytotoxicity in HCC cells. In vivo experiment, combined treatment group with allicin (5 mg/kg/d; every two days for 3 weeks) and 5-FU (20 mg/kg/d; 5 consecutive days) showed a dramatic inhibitory effect on the growth of HCC xenograft tumors in nude mice. The co-treatment group showed highly apoptotic level compared with 5-FU treated alone. Cells combined treatment with allicin and 5-FU increased intracellular reactive oxygen species (ROS) level, reduced mitochondrial membrane potential (ΔΨm), activated caspase-3 and PARP, and down-regulated Bcl-2 compared with DMSO, allicin and 5-FU treated alone. Moreover, the increase of activated caspase-3 and PARP was blocked by the ROS inhibitor antioxidant N-acetyl cysteine (NAC). In conclusion, this is the first study to demonstrate that allicin sensitized HCC cells to 5-FU induced apoptosis through ROS-mediated mitochondrial pathway. These results provided evidences for the combination used of allicin and 5-FU as a novel chemotherapy regimen in HCC. Copyright © 2016 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

  13. Bevacizumab-mediated tumor vasculature remodelling improves tumor infiltration and antitumor efficacy of GD2-CAR T cells in a human neuroblastoma preclinical model.

    PubMed

    Bocca, Paola; Di Carlo, Emma; Caruana, Ignazio; Emionite, Laura; Cilli, Michele; De Angelis, Biagio; Quintarelli, Concetta; Pezzolo, Annalisa; Raffaghello, Lizzia; Morandi, Fabio; Locatelli, Franco; Pistoia, Vito; Prigione, Ignazia

    2017-01-01

    GD2-redirected chimeric antigen receptor (CAR) T lymphocytes represent a promising therapeutic option for immunotherapy of neuroblastoma (NB). However, despite the encouraging therapeutic effects observed in some hematological malignancies, clinical results of CAR T cell immunotherapy in solid tumors are still modest. Tumor driven neo-angiogenesis supports an immunosuppressive microenvironment that influences treatment responses and is amenable to targeting with antiangiogenic drugs. The latter agents promote lymphocyte tumor infiltration by transiently reprogramming tumor vasculature, and may represent a valid combinatorial approach with CAR T cell immunotherapy. In light of these considerations, we investigated the anti-NB activity of GD2-CAR T cells combined with bevacizumab (BEV) in an orthotopic xenograft model of human NB. Two weeks after tumor implantation, mice received BEV or GD2-CAR T cells or both by single intravenous administration. GD2-CAR T cells exerted a significant anti-NB activity only in combination with BEV, even at the lowest concentration tested, which per se did not inhibit tumor growth. When combined with BEV, GD2-CAR T cells massively infiltrated tumor mass where they produced interferon-γ (IFN-γ), which, in turn, induced expression of CXCL10 by NB cells. IFN-γ, and possibly other cytokines, upregulated NB cell expression of PD-L1, while tumor infiltrating GD2-CAR T cells expressed PD-1. Thus, the PD-1/PD-L1 axis can limit the anti-tumor efficacy of the GD2-CAR T cell/BEV association. This study provides a strong rationale for testing the combination of GD2-CAR T cells with BEV in a clinical trial enrolling NB patients. PD-L1 silencing or blocking strategies may further enhance the efficacy of such combination.

  14. Accelerated Tumor Growth Mediated by Sub-lytic Levels of Antibody-Induced Complement Activation is Associated with Activation of the PI3K/AKT Survival Pathway

    PubMed Central

    Wu, Xiaohong; Ragupathi, Govind; Panageas, Katherine; Hong, Feng; Livingston, Philip O.

    2013-01-01

    Purpose We addressed the possibility that low levels of tumor cell bound antibodies targeting gangliosides might accelerate tumor growth. Experimental Design To test this hypothesis, we treated mice with a range of mAb doses against GM2, GD2, GD3 and CD20 after challenge with tumors expressing these antigens and tested the activity of the same mAbs in-vitro. We also explored the mechanisms behind the complement-mediated tumor growth acceleration that we observed and an approach to overcome it. Results Serologically detectable levels of IgM-mAb against GM2 are able to delay or prevent tumor growth of high GM2-expressing cell lines both in-vitro and in a SCID mouse model, while very low levels of this mAb resulted in slight but consistent acceleration of tumor growth in both settings. Surprisingly, this is not restricted to IgM antibodies targeting GM2 but consistent against IgG-mAb targeting GD3 as well. These findings were mirrored by in-vitro studies with antibodies against these antigens as well as GD2 and CD20 (with Rituxan), and shown to be complement-dependent in all cases. Complement-mediated accelerated growth of cultured tumor cell lines initiated by low mAb levels was associated with activation of the PI3K/AKT survival pathway and significantly elevated levels of both p-AKT and p-PRAS40. This complement-mediated PI3K-activation and accelerated tumor growth in-vitro and in-vivo are eliminated by PI3K-inhibitors NVP-BEZ235 and Wortmannin. These PI3K-inhibitors also significantly increased efficacy of high doses of these 4 mAbs. Conclusion Our findings suggest that manipulation of the PI3K/AKT pathway and its signaling network can significantly increase the potency of passively administered mAbs and vaccine-induced-antibodies targeting a variety of tumor-cell-surface-antigens. PMID:23833306

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

    EPA Science Inventory

    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...

  16. Does the Loss of Stromal Caveolin-1 Remodel the Tumor Microenvironment by Activating Src-Mediated PEAK1 and PI3K Pathways

    DTIC Science & Technology

    2017-11-01

    display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE November 2017 2. REPORT TYPE Final 3...communication originating from extracellular vesicles (EVs). We demonstrate that in the context of prostate cancer, EV populations isolated from human...Determine whether EVs, EV-depleted conditioned medium, or both are the functional mediators of angiogenesis and tumor cell migration and invasion . 2

  17. Protein kinase A can block EphA2 receptor–mediated cell repulsion by increasing EphA2 S897 phosphorylation

    PubMed Central

    Barquilla, Antonio; Lamberto, Ilaria; Noberini, Roberta; Heynen-Genel, Susanne; Brill, Laurence M.; Pasquale, Elena B.

    2016-01-01

    The EphA2 receptor tyrosine kinase plays key roles in tissue homeostasis and disease processes such as cancer, pathological angiogenesis, and inflammation through two distinct signaling mechanisms. EphA2 “canonical” signaling involves ephrin-A ligand binding, tyrosine autophosphorylation, and kinase activity; EphA2 “noncanonical” signaling involves phosphorylation of serine 897 (S897) by AKT and RSK kinases. To identify small molecules counteracting EphA2 canonical signaling, we developed a high-content screening platform measuring inhibition of ephrin-A1–induced PC3 prostate cancer cell retraction. Surprisingly, most hits from a screened collection of pharmacologically active compounds are agents that elevate intracellular cAMP by activating G protein–coupled receptors such as the β2-adrenoceptor. We found that cAMP promotes phosphorylation of S897 by protein kinase A (PKA) as well as increases the phosphorylation of several nearby serine/threonine residues, which constitute a phosphorylation hotspot. Whereas EphA2 canonical and noncanonical signaling have been viewed as mutually exclusive, we show that S897 phosphorylation by PKA can coexist with EphA2 tyrosine phosphorylation and block cell retraction induced by EphA2 kinase activity. Our findings reveal a novel paradigm in EphA2 function involving the interplay of canonical and noncanonical signaling and highlight the ability of the β2-adrenoceptor/cAMP/PKA axis to rewire EphA2 signaling in a subset of cancer cells. PMID:27385333

  18. Curcumin inhibits urothelial tumor development by suppressing IGF2 and IGF2-mediated PI3K/AKT/mTOR signaling pathway.

    PubMed

    Tian, Binqiang; Zhao, Yingmei; Liang, Tao; Ye, Xuxiao; Li, Zuowei; Yan, Dongliang; Fu, Qiang; Li, Yonghui

    2017-08-01

    We have previously reported that curcumin inhibits urothelial tumor development in a rat bladder carcinogenesis model. In this study, we report that curcumin inhibits urothelial tumor development by suppressing IGF2 and IGF2-mediated PI3K/AKT/mTOR signaling pathway. Curcumin inhibits IGF2 expression at the transcriptional level and decreases the phosphorylation levels of IGF1R and IRS-1 in bladder cancer cells and N-methyl-N-nitrosourea (MNU)-induced urothelial tumor tissue. Ectopic expression of IGF2 and IGF1R, but not IGF1, in bladder cancer cells restored this process, suggesting that IGF2 is a target of curcumin. Moreover, introduction of constitutively active AKT1 abolished the inhibitory effect of curcumin on cell proliferation, migration, and restored the phosphorylation levels of 4E-BP1 and S6K1, suggesting that curcumin functions via suppressing IGF2-mediated AKT/mTOR signaling pathway. In summary, our results reveal that suppressing IGF2 and IGF2-mediated PI3K/AKT/mTOR signaling pathway is one of the mechanisms of action of curcumin. Our findings suggest a new therapeutic strategy against human bladder cancer caused by aberrant activation of IGF2, which are useful for translational application of curcumin.

  19. Systemic agonistic anti-CD40 treatment of tumor bearing mice modulates hepatic myeloid suppressive cells and causes immune-mediated liver damage

    PubMed Central

    Medina-Echeverz, José; Ma, Chi; Duffy, Austin; Eggert, Tobias; Hawk, Nga; Kleiner, David E.; Korangy, Firouzeh; Greten, Tim F.

    2015-01-01

    Immune stimulatory monoclonal antibodies are currently evaluated as anti tumor agents. Although overall toxicity appears to be moderate, liver toxicities have been reported and are not completely understood. We studied the effect of systemic CD40 antibody treatment on myeloid cells in spleen and liver. Naïve and tumor-bearing mice were treated systemically with agonistic anti-CD40 antibody. Immune cell subsets in liver and spleen, serum transaminases and liver histologies were analyzed after antibody administration. Nox2−/−, Cd40−/− as well as bone marrow chimeric mice were used to study the mechanism by which agonistic anti-CD40 mediates its effects in vivo. Suppressor function of murine and human tumor-induced myeloid derived suppressive cells was studied upon CD40 ligation. Agonistic CD40 antibody caused liver damage within 24 hours after injection in two unrelated tumor models and mice strains. Using bone marrow chimeras we demonstrated that CD40 antibody-induced hepatitis in tumor-bearing mice was dependent on the presence of CD40-expressing hematopoietic cells. Agonistic CD40 ligation-dependent liver damage was induced by the generation of reactive oxygen species. Furthermore, agonistic CD40 antibody resulted in increased CD80 and CD40 positive liver CD11b+Gr-1+ immature myeloid cells. CD40 ligation on tumor-induced murine and human CD14+HLA-DRlow PBMC from cancer patients reduced their immune suppressor function. Collectively, agonistic CD40 antibody treatment activated tumor-induced, myeloid cells, caused myeloid dependent hepatotoxicity and ameliorated the suppressor function of murine and human MDSC. Collectively, our data suggests that CD40 may mature immunosuppressive myeloid cells and thereby cause liver damage in mice with an accumulation of tumor-induced hepatic MDSC. PMID:25637366

  20. p53-mediated up-regulation of CD95 is not involved in genotoxic drug-induced apoptosis of human breast tumor cells.

    PubMed

    Ruiz-Ruiz, M C; López-Rivas, A

    1999-03-01

    Induction of CD95 (Fas/APO-1) and CD95 ligand during chemotherapeutic treatment may contribute to the death by apoptosis of some tumor cells. In this study, we have analyzed the role of the CD95 system in genotoxic drug-induced death of human breast tumor cells. Incubation of the breast tumor cell lines MCF-7 and EVSA-T with doxorubicin or methotrexate caused apoptosis after 48 h of treatment. These drugs induced a marked increase in the level of CD95 mRNA and protein in wild-type p53-expressing MCF-7 cells. On the contrary, the breast cancer cell line EVSA-T that expresses high levels of an inactive form of p53, did not up-regulate CD95 upon drug treatment. Elevation of CD95 expression by DNA-damaging drugs was notably blocked in MCF-7 cells expressing the human papillomavirus type 16 E6 protein (E6 cells) which prevented p53 accumulation upon DNA damage. However, E6 cells were still killed by the drugs. Furthermore, the genotoxic drugs did not induce the expression of CD95 ligand in MCF-7 cells at doses that caused apoptosis in these breast tumor cells. Moreover, drug-induced apoptosis of breast tumor cells was not prevented in the presence of either a CD95 antagonistic antibody or a CD95 ligand blocking antibody. We also observed a strong synergism between lower doses of DNA-damaging drugs and CD95 agonistic antibody in the induction of apoptosis in MCF-7 cells. In summary, our data indicate that drug-induced apoptosis of breast tumor cells occurs by a CD95/CD95L-independent mechanism although by elevating the tumor suppressor proteins p53 and CD95, genotoxic drugs may sensitize breast tumor cells to CD95-mediated apoptosis.

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

    PubMed

    Zhi, Feng; Dong, Haifeng; Jia, Xuefeng; Guo, Wenjie; Lu, Huiting; Yang, Yilin; Ju, Huangxian; Zhang, Xueji; Hu, Yiqiao

    2013-01-01

    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-21)PPGADR. 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.

  2. Chronic constriction injury-induced nociception is relieved by nanomedicine-mediated decrease of rat hippocampal tumor necrosis factor.

    PubMed

    Gerard, Elizabeth; Spengler, Robert N; Bonoiu, Adela C; Mahajan, Supriya D; Davidson, Bruce A; Ding, Hong; Kumar, Rajiv; Prasad, Paras N; Knight, Paul R; Ignatowski, Tracey A

    2015-07-01

    Neuropathic pain is a chronic pain syndrome that arises from nerve injury. Current treatments only offer limited relief, clearly indicating the need for more effective therapeutic strategies. Previously, we demonstrated that proinflammatory tumor necrosis factor-alpha (TNF) is a key mediator of neuropathic pain pathogenesis; TNF is elevated at sites of neuronal injury, in the spinal cord, and supraspinally during the initial development of pain. The inhibition of TNF action along pain pathways outside higher brain centers results in transient decreases in pain perception. The objective of this study was to determine whether specific blockade of TNF in the hippocampus, a site of pain integration, could prove efficacious in reducing sciatic nerve chronic constriction injury (CCI)-induced pain behavior. Small inhibitory RNA directed against TNF mRNA was complexed to gold nanorods (GNR-TNF siRNA; TNF nanoplexes) and injected into the contralateral hippocampus of rats 4 days after unilateral CCI. Withdrawal latencies to a noxious thermal stimulus (hyperalgesia) and withdrawal to innocuous forces (allodynia) were recorded up to 10 days and compared with baseline values and sham-operated rats. Thermal hyperalgesia was dramatically decreased in CCI rats receiving hippocampal TNF nanoplexes; and mechanical allodynia was transiently relieved. TNF levels (bioactive protein, TNF immunoreactivity) in hippocampal tissue were decreased. The observation that TNF nanoplex injection into the hippocampus alleviated neuropathic pain-like behavior advances our previous findings that hippocampal TNF levels modulate pain perception. These data provide evidence that targeting TNF in the brain using nanoparticle-protected siRNA may be an effective strategy for treatment of neuropathic pain.

  3. Adenosine A(2A) agonist and A(2B) antagonist mediate an inhibition of inflammation-induced contractile disturbance of a rat gastrointestinal preparation.

    PubMed

    Michael, Sebastian; Warstat, Claudia; Michel, Fabien; Yan, Luo; Müller, Christa E; Nieber, Karen

    2010-03-01

    Adenosine can show anti-inflammatory as well as pro-inflammatory activities. The contribution of the specific adenosine receptor subtypes in various cells, tissues and organs is complex. In this study, we examined the effect of the adenosine A(2A) receptor agonist CGS 21680 and the A(2B)R antagonist PSB-1115 on acute inflammation induced experimentally by 2,4,6-trinitrobenzenesulfonic acid (TNBS) on rat ileum/jejunum preparations. Pre-incubation of the ileum/jejunum segments with TNBS for 30 min resulted in a concentration-dependent inhibition of acetylcholine (ACh)-induced contractions. Pharmacological activation of the A(2A)R with CGS 21680 (0.1-10 microM) pre-incubated simultaneously with TNBS (10 mM) prevented concentration-dependently the TNBS-induced inhibition of the ACh contractions. Stimulation of A(2B)R with the selective agonist BAY 60-6583 (10 microM) did neither result in an increase nor in a further decrease of ACh-induced contractions compared to the TNBS-induced inhibition. The simultaneous pre-incubation of the ileum/jejunum segments with TNBS (10 mM) and the selective A(2B)R antagonist PSB-1115 (100 microM) inhibited the contraction-decreasing effect of TNBS. The effects of the A(2A)R agonist and the A(2B)R antagonist were in the same range as the effect induced by 1 microM methotrexate. The combination of the A(2A)R agonist CGS 21680 and the A(2B)R antagonist PSB-1115 at subthreshold concentrations of both agents found a significant amelioration of the TNBS-diminished contractility. Our results demonstrate that the activation of A(2A) receptors or the blockade of the A(2B) receptors can prevent the inflammation-induced disturbance of the ACh-induced contraction in TNBS pre-treated small intestinal preparations. The combination of both may be useful for the treatment of inflammatory bowel diseases.

  4. Blocking heme oxygenase-1 by zinc protoporphyrin reduces tumor hypoxia-mediated VEGF release and inhibits tumor angiogenesis as a potential therapeutic agent against colorectal cancer.

    PubMed

    Cheng, Chun-Chia; Guan, Siao-Syun; Yang, Hao-Jhih; Chang, Chun-Chao; Luo, Tsai-Yueh; Chang, Jungshan; Ho, Ai-Sheng

    2016-01-28

    Hypoxia in tumor niche is one of important factors to start regeneration of blood vessels, leading to increase survival, proliferation, and invasion in cancer cells. Under hypoxia microenvironment, furthermore, steadily increased hypoxia-inducible factor -1α (HIF-1α) is observed, and can increase vascular endothelial growth factor (VEGF) expression and promote angiogenesis. Zinc protoporphyrin (ZnPP), a heme oxygenase-1 (HO-1) inhibitor, is potential to inhibit tumor proliferation and progression. However, the mechanism of ZnPP in inhibition of tumor is not completely clear. We hypothesize that ZnPP may modulate HIF-1α through inhibiting HO-1, and then inhibit angiogenesis and tumor progression. This study aimed to dissect the mechanism of ZnPP in tumor suppression. We observed the amount of VEGF was increased in the sera of the colorectal cancer (CRC) patients (n = 34, p < 0.05). Furthermore, increased VEGF expression was also measured in colorectal cancer cells, HCT-15, culturing under mimicking hypoxic condition. It suggested that hypoxia induced VEGF production from cancer cells. VEGF production was significantly reduced from HCT-15 cells after exposure to HIF-1α inhibitor KC7F2, suggesting that HIF-1α regulated VEGF production. Moreover, we observed that the HO-1 inhibitor ZnPP inhibited the expressions of HIF-1α and VEGF coupled with cell proliferations of HCT-15 cells, suggesting that ZnPP blocked HIF-1α expression, and then inhibited the consequent VEGF production. In the xenograft model, we also observed that the animals exposed to ZnPP displayed much smaller tumor nodules and less degree of angiogenesis with decreased expression of the angiogenesis marker, αvβ3 integrin, compared to that in normal control. This study demonstrated that VEGF level in serum was elevated in the patients with CRC. The HO-1 inhibitor, ZnPP, possessed the properties of anti-tumor agent by decreasing HIF-1α levels, blocking VEGF production, impairing tumor

  5. Effect of the efflux pump QepA2 combined with chromosomally mediated mechanisms on quinolone resistance and bacterial fitness in Escherichia coli.

    PubMed

    Machuca, Jesús; Briales, Alejandra; Díaz-de-Alba, Paula; Martínez-Martínez, Luis; Pascual, Álvaro; Rodríguez-Martínez, José-Manuel

    2015-09-01

    The aim of the study was to determine the interplay between the plasmid-mediated qepA2 gene and multiple chromosomally mediated fluoroquinolone resistance determinants in the development of fluoroquinolone resistance in Escherichia coli and its influence on bacterial fitness. E. coli ATCC 25922 and derived isogenic strains harbouring different chromosomally mediated fluoroquinolone resistance determinants were electroporated with pBK-CMV vector encoding QepA2. The MICs of fluoroquinolones were determined by standardized microdilution. The mutant prevention concentration (MPC) was evaluated. Bacterial fitness was analysed using ΔlacZ system competition assays. The ciprofloxacin MIC for strains harbouring the qepA2 gene was 4- to 8-fold higher compared with strains without the qepA2 gene. The qepA2 gene also increased the MPC of ciprofloxacin 4- to 16-fold. Combination of the qepA2 gene plus two to three additional mechanisms conferred a clinically relevant resistance level. The presence of the qepA2 gene was associated with fitness costs in strains with mutations in the gyrA and/or parC genes, although the presence of an additional deletion of the marR gene compensated for this fitness cost by increasing bacterial fitness by 5%-23%. The additive effect of chromosomally mediated fluoroquinolone resistance mechanisms and the qepA2 gene led to clinical levels of fluoroquinolone resistance. Under competitive conditions, the qepA2 gene had a biological cost in E. coli that was compensated for by the presence of an additional deletion in the marR gene. © The Author 2015. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  6. Immune-Mediated Fever in the Dog. Occurrence of Antinuclear Antibodies, Rheumatoid Factor, Tumor Necrosis Factor and Interleukin-6 in Serum

    PubMed Central

    Bohnhorst, Øvrebø; Hanssen, I; Moen, Torolf

    2002-01-01

    Contents of antinuclear antibodies (ANA), rheumatoid factor (RF), tumor necrosis factor (TNF-α) and interleukin-6 (IL-6) were measured in serum from 20 dogs with immune-mediated fever. Seven out of 20 patients were ANA positive, 1 out of 20 was positive to antibodies against extractable nuclear antigens (ENA), 1 out of 20 was positive to antibodies against deoxynucleoproteins (DNP), 2 out of 13 were RF positive and none out of 20 patients had antibodies against native DNA in the serum. TNF-α was not detected in any serum of 15 dogs with immune-mediated fever, while 10 out of 13 presented with elevated IL-6. The results varied between patients, but the IL-6 level was high in most of them. This indicate a role for IL-6 in the pathogenesis of immune-mediated fever in most cases. PMID:12564546

  7. Tumor Cells Surviving Exposure to Proton or Photon Radiation Share a Common Immunogenic Modulation Signature, Rendering Them More Sensitive to T Cell–Mediated Killing

    SciTech Connect

    Gameiro, Sofia R.; Malamas, Anthony S.; Bernstein, Michael B.

    2016-05-01

    Purpose: To provide the foundation for combining immunotherapy to induce tumor antigen–specific T cells with proton radiation therapy to exploit the activity of those T cells. Methods and Materials: Using cell lines of tumors frequently treated with proton radiation, such as prostate, breast, lung, and chordoma, we examined the effect of proton radiation on the viability and induction of immunogenic modulation in tumor cells by flow cytometric and immunofluorescent analysis of surface phenotype and the functional immune consequences. Results: These studies show for the first time that (1) proton and photon radiation induced comparable up-regulation of surface molecules involved in immune recognition (histocompatibilitymore » leukocyte antigen, intercellular adhesion molecule 1, and the tumor-associated antigens carcinoembryonic antigen and mucin 1); (2) proton radiation mediated calreticulin cell-surface expression, increasing sensitivity to cytotoxic T-lymphocyte killing of tumor cells; and (3) cancer stem cells, which are resistant to the direct cytolytic activity of proton radiation, nonetheless up-regulated calreticulin after radiation in a manner similar to non-cancer stem cells. Conclusions: These findings offer a rationale for the use of proton radiation in combination with immunotherapy, including for patients who have failed radiation therapy alone or have limited treatment options.« less

  8. 3-Bromopyruvate and sodium citrate target glycolysis, suppress survivin, and induce mitochondrial-mediated apoptosis in gastric cancer cells and inhibit gastric orthotopic transplantation tumor growth

    PubMed Central

    WANG, TING-AN; ZHANG, XIAO-DONG; GUO, XING-YU; XIAN, SHU-LIN; LU, YUN-FEI

    2016-01-01

    Glycolysis is the primary method utilized by cancer cells to produce the energy (adenosine triphosphate, ATP) required for cell proliferation. Therefore, inhibition of glycolysis may inhibit tumor growth. We previously found that both 3-bromopyruvate (3-BrPA) and sodium citrate (SCT) can inhibit glycolysis in vitro; however, the underlying inhibitory mechanisms remain unclear. In the present study, we used a human gastric cancer cell line (SGC-7901) and an orthotopic transplantation tumor model in nude mice to explore the specific mechanisms of 3-BrPA and SCT. We found that both 3-BrPA and SCT effectively suppressed cancer cell proliferation, arrested the cell cycle, induced apoptosis, and decreased the production of lactate and ATP. 3-BrPA significantly reduced the glycolytic enzyme hexokinase activity, while SCT selectively inhibited phosphofructokinase-1 activity. Furthermore, 3-BrPA and SCT upregulated the expression of pro-apoptotic proteins (Bax, cytochrome c, and cleaved caspase-3) and downregulated the expression of anti-apoptotic proteins (Bcl-2 and survivin). Finally, our animal model of gastric cancer indicated that intraperitoneal injection of 3-BrPA and SCT suppressed orthotopic transplantation tumor growth and induced tumor apoptosis. Taken together, these results suggest that 3-BrPA and SCT selectively suppress glycolytic enzymes, decrease ATP production, induce mitochondrial-mediated apoptosis, downregulate survivin, and inhibit tumor growth. Moreover, an intraperitoneal injection is an effective form of administration of 3-BrPA and SCT. PMID:26708213

  9. Antisecretory Factor-mediated Inhibition of Cell Volume Dynamics Produces Anti-tumor Activity in Glioblastoma. | Office of Cancer Genomics

    Cancer.gov

    Interstitial fluid pressure (IFP) presents a barrier to drug uptake in solid tumors, including the aggressive primary brain tumor glioblastoma multiforme (GBM). It remains unclear how fluid dynamics impacts tumor progression and can be targeted therapeutically. To address this issue, a novel telemetry-based approach was developed to measure changes in IFP during progression of GBM xenografts. Antisecretory factor (AF) is an endogenous protein that displays anti-secretory effects in animals and patients.

  10. A Novel Anti-CEACAM5 Monoclonal Antibody, CC4, Suppresses Colorectal Tumor Growth and Enhances NK Cells-Mediated Tumor Immunity

    PubMed Central

    Lu, Di; Wang, Ping; Xing, Shu; Coll, Jean-Luc; Yang, Dongling; Yan, Xiyun

    2011-01-01

    Carcinoembryonic antigen (CEA, CEACAM5, and CD66e) has been found to be associated with various types of cancers, particularly colorectal carcinoma, and developed to be a molecular target for cancer diagnosis and therapy. In present study, we generated a novel anti-CEACAM5 monoclonal antibody, namely mAb CC4, by immunizing mice with living colorectal cancer LS174T cells. Immunohistochemical studies found that mAb CC4 specifically and strongly binds to tumor tissues, especially colorectal adenocarcinoma. In xenografted mice, mAb CC4 is specifically accumulated in tumor site and remarkably represses colorectal tumor growth. In vitro functional analysis showed that mAb CC4 significantly suppresses cell proliferation, migration and aggregation of colorectal cancer cells and also raises strong ADCC reaction. More interestingly, mAb CC4 is able to enhance NK cytotoxicity against MHC-I-deficient colorectal cancer cells by blocking intercellular interaction between epithelial CEACAM5 and NK inhibitory receptor CEACAM1. These data suggest that mAb CC4 has the potential to be developed as a novel tumor-targeting carrier and cancer therapeutic. PMID:21731662

  11. Targeting Vascular Endothelial-Cadherin in Tumor-Associated Blood Vessels Promotes T-cell-Mediated Immunotherapy.

    PubMed

    Zhao, Yang; Ting, Ka Ka; Li, Jia; Cogger, Victoria C; Chen, Jinbiao; Johansson-Percival, Anna; Ngiow, Shin Foong; Holst, Jeff; Grau, Georges; Goel, Shom; Muller, Thorleif; Dejana, Elisabetta; McCaughan, Geoff; Smyth, Mark J; Ganss, Ruth; Vadas, Mathew A; Gamble, Jennifer R

    2017-08-15

    T-cell infiltration of solid tumors is associated with improved prognosis and favorable responses to immunotherapy. Mechanisms that enable tumor infiltration of CD8 + T cells have not been defined, nor have drugs that assist this process been discovered. Here we address these issues with a focus on VE-cadherin, a major endothelial cell-specific junctional protein that controls vascular integrity. A decrease in VE-cadherin expression is associated with tumor pathology. We developed an oligonucleotide-based inhibitor (CD5-2), which disrupted the interaction of VE-cadherin with its regulator miR-27a, resulting in increased VE-cadherin expression. Administration of CD5-2 in tumor-bearing mice enhanced expression of VE-cadherin in tumor endothelium, activating TIE-2 and tight junction pathways and normalizing vessel structure and function. CD5-2 administration also enhanced tumor-specific T-cell infiltration and spatially redistributed CD8 + T cells within the tumor parenchyma. Finally, CD5-2 treatment enhanced the efficacy of anti-PD-1 blocking antibody. Our work establishes a role for VE-cadherin in T-cell infiltration in tumors and offers a preclinical proof of concept for CD5-2 as a therapeutic modifier of cancer immunotherapy via effects on the tumor vasculature. Cancer Res; 77(16); 4434-47. ©2017 AACR . ©2017 American Association for Cancer Research.

  12. Radiation and inhibition of angiogenesis by canstatin synergize to induce HIF-1α–mediated tumor apoptotic switch

    PubMed Central

    Magnon, Claire; Opolon, Paule; Ricard, Marcel; Connault, Elisabeth; Ardouin, Patrice; Galaup, Ariane; Métivier, Didier; Bidart, Jean-Michel; Germain, Stéphane; Perricaudet, Michel; Schlumberger, Martin

    2007-01-01

    Tumor radioresponsiveness depends on endothelial cell death, which leads in turn to tumor hypoxia. Radiation-induced hypoxia was recently shown to trigger tumor radioresistance by activating angiogenesis through hypoxia-inducible factor 1–regulated (HIF-1–regulated) cytokines. We show here that combining targeted radioiodide therapy with angiogenic inhibitors, such as canstatin, enhances direct tumor cell apoptosis, thereby overcoming radio-induced HIF-1–dependent tumor survival pathways in vitro and in vivo. We found that following dual therapy, HIF-1α increases the activity of the canstatin-induced αvβ5 signaling tumor apoptotic pathway and concomitantly abrogates mitotic checkpoint and tetraploidy triggered by radiation. Apoptosis in conjunction with mitotic catastrophe leads to lethal tumor damage. We discovered that HIF-1 displays a radiosensitizing activity that is highly dependent on treatment modalities by regulating key apoptotic molecular pathways. Our findings therefore support a crucial role for angiogenesis inhibitors in shifting the fate of radiation-induced HIF-1α activity from hypoxia-induced tumor radioresistance to hypoxia-induced tumor apoptosis. This study provides a basis for developing new biology-based clinically relevant strategies to improve the efficacy of radiation oncology, using HIF-1 as an ally for cancer therapy. PMID:17557121

  13. AAVrh.10-mediated genetic delivery of bevacizumab to the pleura to provide local anti-VEGF to suppress growth of metastatic lung tumors.

    PubMed

    Watanabe, M; Boyer, J L; Crystal, R G

    2010-08-01

    Vascular endothelial growth factor (VEGF) produced by tumor cells has a central role in stimulating angiogenesis required for tumor growth. Humanized monoclonal anti-VEGF antibody (bevacizumab, Avastin), approved as a treatment for non-squamous, non-small cell lung cancer, requires administration every 3 weeks. We hypothesized that an intrapleural administration of an adeno-associated virus (AAV) vector expressing an anti-VEGF-A antibody equivalent of bevacizumab would result in sustained anti-VEGF-A localized expression within the lung and suppress metastatic tumor growth. The AAV vector AAVrh.10alphaVEGF encodes the light chain and heavy chain complementary DNAs of monoclonal antibody A.4.6.1, a murine antibody that specifically recognizes human VEGF-A with the same antigen-binding site as bevacizumab. A metastatic lung tumor model was established in severe combined immunodeficient mice by intravenous administration of human DU145 prostate carcinoma cells. Intrapleural administration of AAVrh.10alphaVEGF directed long-term expression of the anti-human VEGF-A antibody in lung, as shown by sustained, high-level anti-human VEGF titers in lung epithelial lining fluid for 40 weeks, which was the duration of the study. In the AAVrh.10alphaVEGF-treated animals, tumor growth was significantly suppressed (P<0.05), the numbers of blood vessels and mitotic nuclei in the tumor was decreased (P<0.05) and there was increased survival (P<0.05). Thus, intrapleural administration of an AAVrh.10 vector, encoding the murine monoclonal antibody equivalent of bevacizumab, effectively suppresses the growth of metastatic lung tumors, suggesting AAV-mediated gene transfer to the pleura to deliver bevacizumab locally to the lung as a novel alternative platform to conventional monoclonal antibody therapy.

  14. Metal based imaging probes of DO3A-Act-Met for LAT1 mediated methionine specific tumors: synthesis and preclinical evaluation.

    PubMed

    Kadiyala, K Ganesh; Datta, Anupama; Tanwar, Jyoti; Adhikari, Anupriya; Kumar, B S Hemanth; Chuttani, Krishna; Thirumal, Meganathan; Mishra, Anil K

    2015-03-01

    Tumor cells are known to have an elevated requirement for methionine due to increased protein synthesis and trans-methylation reactions. A methionine based macrocyclic tumor imaging system, DO3A-Act-Met, has been designed to provide a novel platform for tumor imaging via modalities, PET/MRI using metal ions, (68)Ga and (157)Gd. Synthesis of DO3A-Act-Met was confirmed through NMR and mass spectrometric techniques. Cytotoxicity of complexes was evaluated using MTT assay whereas receptor binding and trans-stimulation studies were performed on EAT and U-87 MG cell lines. Tumor targeting was assessed through imaging and biodistribution experiments on U-87 MG xenograft model. DO3A-Act-Met was synthesized and radiolabeled with (68)Ga in high radiochemical purity (85-92%). The receptor binding assay on EAT cells predicted high binding affinity with Kd of 0.78 nM. Efflux of (35)S-L-methionine trans-stimulated by extracellular DO3A-Act-Met on U-87MG cells suggested an L-system transport. MR studies revealed a longitudinal relaxivity of 4.35 mM(-1) s(-1) for Gd-DO3A-Act-Met and a 25% signal enhancement at tumor site. The biodistribution studies in U-87MG xenografts validated tumor specificity. DO3A-Act-Met, a methionine conjugated probe is a promising agent for targeted molecular imaging, exhibiting high specificity towards tumor owing to its essential role in proliferation of cancer cells mediated through LAT1.

  15. Tumor site-specific silencing of NF-κB p65 by targeted hollow gold nanospheres-mediated photothermal transfection

    PubMed Central

    Lu, Wei; Zhang, Guodong; Zhang, Rui; Flores, Leo G; Huang, Qian; Gelovani, Juri G; Li, Chun

    2010-01-01

    Nuclear factor-κB (NF-κB) transcription factor is a critical regulator of the expression of genes involved in tumor formation and progression. Successful RNA interference (RNAi) therapeutics targeting NF-κB is challenged by siRNA delivery systems, which can render targeted in vivo delivery, efficient endo-lysosomal escape and dynamic control over activation of RNAi. Here, we report near-infrared light-inducible NF-κB down-regulation through folate receptor-targeted hollow gold nanospheres carrying siRNA recognizing NF-κB p65 subunit. Using micro-positron emission tomography/computed tomography imaging, the targeted nanoconstructs exhibited significantly higher tumor uptake in nude mice-bearing HeLa cervical cancer xenografts than non-targeted nanoparticles following intravenous administration. Mediated by hollow gold nanospheres, controllable cytoplasmic delivery of siRNA was obtained upon near-infrared light irradiation through photothermal effect. Efficient down-regulation of NF-κB p65 was achieved only in tumors irradiated with near-infrared light, but not in non-irradiated tumors grown in the same mice. Liver, spleen, kidney, and lung were not affected by the treatments, in spite of significant uptake of the siRNA nanoparticles in these organs. We term this mode of action “photothermal transfection”. Combined treatments with p65 siRNA photothermal transfection and irinotecan caused substantially enhanced tumor apoptosis and significant tumor growth delay compared with other treatment regimens. Therefore, photothermal transfection of NF-κB p65 siRNA could effectively sensitize the tumor to chemotherapeutic agents. Because NIR light can penetrate skin and be delivered with high spatiotemporal control, therapeutic RNAi may benefit from this novel transfection strategy while avoiding unwanted side effect. PMID:20388791

  16. Anti-Tumor Activity of a Novel Compound-CDF Is Mediated by Regulating miR-21, miR-200, and PTEN in Pancreatic Cancer

    PubMed Central

    Kong, Dejuan; Sarkar, Sanila H.; Wang, Zhiwei; Banerjee, Sanjeev; Aboukameel, Amro; Padhye, Subhash; Philip, Philip A.; Sarkar, Fazlul H.

    2011-01-01

    Background The existence of cancer stem cells (CSCs) or cancer stem-like cells in a tumor mass is believed to be responsible for tumor recurrence because of their intrinsic and extrinsic drug-resistance characteristics. Therefore, targeted killing of CSCs would be a newer strategy for the prevention of tumor recurrence and/or treatment by overcoming drug-resistance. We have developed a novel synthetic compound-CDF, which showed greater bioavailability in animal tissues such as pancreas, and also induced cell growth inhibition and apoptosis, which was mediated by inactivation of NF-κB, COX-2, and VEGF in pancreatic cancer (PC) cells. Methodology/Principal Findings In the current study we showed, for the first time, that CDF could significantly inhibit the sphere-forming ability (pancreatospheres) of PC cells consistent with increased disintegration of pancreatospheres, which was associated with attenuation of CSC markers (CD44 and EpCAM), especially in gemcitabine-resistant (MIAPaCa-2) PC cells containing high proportion of CSCs consistent with increased miR-21 and decreased miR-200. In a xenograft mouse model of human PC, CDF treatment significantly inhibited tumor growth, which was associated with decreased NF-κB DNA binding activity, COX-2, and miR-21 expression, and increased PTEN and miR-200 expression in tumor remnants. Conclusions/Significance These results strongly suggest that the anti-tumor activity of CDF is associated with inhibition of CSC function via down-regulation of CSC-associated signaling pathways. Therefore, CDF could be useful for the prevention of tumor recurrence and/or treatment of PC with better treatment outcome in the future. PMID:21408027

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

    PubMed

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

    2017-09-01

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

  18. Three-dimensional microfluidic collagen hydrogels for investigating flow-mediated tumor-endothelial signaling and vascular organization.

    PubMed

    Buchanan, Cara F; Voigt, Elizabeth E; Szot, Christopher S; Freeman, Joseph W; Vlachos, Pavlos P; Rylander, Marissa Nichole

    2014-01-01

    Hyperpermeable tumor vessels are responsible for elevated interstitial fluid pressure and altered flow patterns within the tumor microenvironment. These aberrant hydrodynamic stresses may enhance tumor development by stimulating the angiogenic activity of endothelial cells lining the tumor vasculature. However, it is currently not known to what extent shear forces affect endothelial organization or paracrine signaling during tumor angiogenesis. The objective of this study was to develop a three-dimensional (3D), in vitro microfluidic tumor vascular model for coculture of tumor and endothelial cells under varying flow shear stress conditions. A central microchannel embedded within a collagen hydrogel functions as a single neovessel through which tumor-relevant hydrodynamic stresses are introduced and quantified using microparticle image velocimetry (μ-PIV). This is the first use of μ-PIV in a tumor representative, 3D collagen matrix comprised of cylindrical microchannels, rather than planar geometries, to experimentally measure flow velocity and shear stress. Results demonstrate that endothelial cells develop a confluent endothelium on the microchannel lumen that maintains integrity under physiological flow shear stresses. Furthermore, this system provides downstream molecular analysis capability, as demonstrated by quantitative RT-PCR, in which, tumor cells significantly increase expression of proangiogenic genes in response to coculture with endothelial cells under low flow conditions. This work demonstrates that the microfluidic in vitro cell culture model can withstand a range of physiological flow rates and permit quantitative measurement of wall shear stress at the fluid-collagen interface using μ-PIV optical flow diagnostics, ultimately serving as a versatile platform for elucidating the role of fluid forces on tumor-endothelial cross talk.

  19. Protease-activated Receptor-2 (PAR-2)-mediated Nf-κB Activation Suppresses Inflammation-associated Tumor Suppressor MicroRNAs in Oral Squamous Cell Carcinoma*

    PubMed Central

    Johnson, Jeff J.; Miller, Daniel L.; Jiang, Rong; Liu, Yueying; Shi, Zonggao; Tarwater, Laura; Williams, Russell; Balsara, Rashna; Sauter, Edward R.; Stack, M. Sharon

    2016-01-01

    Oral cancer is the sixth most common cause of death from cancer with an estimated 400,000 deaths worldwide and a low (50%) 5-year survival rate. The most common form of oral cancer is oral squamous cell carcinoma (OSCC). OSCC is highly inflammatory and invasive, and the degree of inflammation correlates with tumor aggressiveness. The G protein-coupled receptor protease-activated receptor-2 (PAR-2) plays a key role in inflammation. PAR-2 is activated via proteolytic cleavage by trypsin-like serine proteases, including kallikrein-5 (KLK5), or by treatment with activating peptides. PAR-2 activation induces G protein-α-mediated signaling, mobilizing intracellular calcium and Nf-κB signaling, leading to the increased expression of pro-inflammatory mRNAs. Little is known, however, about PAR-2 regulation of inflammation-related microRNAs. Here, we assess PAR-2 expression and function in OSCC cell lines and tissues. Stimulation of PAR-2 activates Nf-κB signaling, resulting in RelA nuclear translocation and enhanced expression of pro-inflammatory mRNAs. Concomitantly, suppression of the anti-inflammatory tumor suppressor microRNAs let-7d, miR-23b, and miR-200c was observed following PAR-2 stimulation. Analysis of orthotopic oral tumors generated by cells with reduced KLK5 expression showed smaller, less aggressive lesions with reduced inflammatory infiltrate relative to tumors generated by KLK5-expressing control cells. Together, these data support a model wherein KLK5-mediated PAR-2 activation regulates the expression of inflammation-associated mRNAs and microRNAs, thereby modulating progression of oral tumors. PMID:26839311

  20. Soluble monomeric EphrinA1 is released from tumor cells and is a functional ligand for the EphA2 receptor

    PubMed Central

    Wykosky, J; Palma, E; Gibo, DM; Ringler, S; Turner, CP; Debinski, W

    2013-01-01

    The ephrinA1 ligand exerts antioncogenic effects in tumor cells through activation and downregulation of the EphA2 receptor and has been described as a membrane-anchored protein requiring clustering for function. However, while investigating the ephrinA1/EphA2 system in the pathobiology of glioblastoma multiforme (GBM), we uncovered that ephrinA1 is released from GBM and breast adenocarcinoma cells as a soluble, monomeric protein and is a functional form of the ligand in this state. Conditioned media containing a soluble monomer of ephrinA1 caused EphA2 internalization and downregulation, dramatic alteration of cell morphology and suppression of the Ras–MAPK pathway. Moreover, soluble monomeric ephrinA1 was functional in a physiological context, eliciting collapse of embryonic neuronal growth cones. We also found that ephrinA1 is cleaved from the plasma membrane of GBM cells, an event which involves the action of a metalloprotease. Thus, the ephrinA1 ligand can, indeed, function as a soluble monomer and may act in a paracrine manner on the EphA2 receptor without the need for juxtacrine interactions. These findings have important implications for further deciphering the function of these proteins in pathology and physiology, as well as for the design of ephrinA1-based EphA2-targeted antitumor therapeutics. PMID:18794797

  1. Soluble monomeric EphrinA1 is released from tumor cells and is a functional ligand for the EphA2 receptor.

    PubMed

    Wykosky, J; Palma, E; Gibo, D M; Ringler, S; Turner, C P; Debinski, W

    2008-12-11

    The ephrinA1 ligand exerts antioncogenic effects in tumor cells through activation and downregulation of the EphA2 receptor and has been described as a membrane-anchored protein requiring clustering for function. However, while investigating the ephrinA1/EphA2 system in the pathobiology of glioblastoma multiforme (GBM), we uncovered that ephrinA1 is released from GBM and breast adenocarcinoma cells as a soluble, monomeric protein and is a functional form of the ligand in this state. Conditioned media containing a soluble monomer of ephrinA1 caused EphA2 internalization and downregulation, dramatic alteration of cell morphology and suppression of the Ras-MAPK pathway. Moreover, soluble monomeric ephrinA1 was functional in a physiological context, eliciting collapse of embryonic neuronal growth cones. We also found that ephrinA1 is cleaved from the plasma membrane of GBM cells, an event which involves the action of a metalloprotease. Thus, the ephrinA1 ligand can, indeed, function as a soluble monomer and may act in a paracrine manner on the EphA2 receptor without the need for juxtacrine interactions. These findings have important implications for further deciphering the function of these proteins in pathology and physiology, as well as for the design of ephrinA1-based EphA2-targeted antitumor therapeutics.

  2. Reduced NADPH oxidase type 2 activity mediates sleep fragmentation-induced effects on TC1 tumors in mice.

    PubMed

    Zheng, Jiamao; Almendros, Isaac; Wang, Yang; Zhang, Shelley X; Carreras, Alba; Qiao, Zhuanhong; Gozal, David

    2015-02-01

    The molecular mechanisms underlying how sleep fragmentation (SF) influences cancer growth and progression remain largely elusive. Here, we present evidence that SF reduced ROS production by downregulating gp91 phox expression and activity in TC1 cell tumor associated macrophages (TAMs), while genetic ablation of phagocytic Nox2 activity increased tumor cell proliferation, motility, invasion, and extravasation in vitro . Importantly, the in vivo studies using immunocompetent syngeneic murine tumor models suggested that Nox2 deficiency mimics SF-induced TAMs infiltration and subsequent tumor growth and invasion. Taken together, these studies reveal that perturbed sleep could adversely affect innate immunity within the tumor by altering Nox2 expression and activity, and indicate that selective potentiation of Nox2 activity may present a novel therapeutic strategy in the treatment of cancer.

  3. Reduced NADPH oxidase type 2 activity mediates sleep fragmentation-induced effects on TC1 tumors in mice

    PubMed Central

    Zheng, Jiamao; Almendros, Isaac; Wang, Yang; Zhang, Shelley X; Carreras, Alba; Qiao, Zhuanhong; Gozal, David

    2015-01-01

    The molecular mechanisms underlying how sleep fragmentation (SF) influences cancer growth and progression remain largely elusive. Here, we present evidence that SF reduced ROS production by downregulating gp91phox expression and activity in TC1 cell tumor associated macrophages (TAMs), while genetic ablation of phagocytic Nox2 activity increased tumor cell proliferation, motility, invasion, and extravasation in vitro. Importantly, the in vivo studies using immunocompetent syngeneic murine tumor models suggested that Nox2 deficiency mimics SF-induced TAMs infiltration and subsequent tumor growth and invasion. Taken together, these studies reveal that perturbed sleep could adversely affect innate immunity within the tumor by altering Nox2 expression and activity, and indicate that selective potentiation of Nox2 activity may present a novel therapeutic strategy in the treatment of cancer. PMID:25949873

  4. IFN-γ-independent intraocular tumor rejection is mediated by a macrophage-dependent process that leaves the eye intact

    PubMed Central

    Coursey, Terry G.; Chen, Peter W.; Niederkorn, Jerry Y.

    2012-01-01

    Intraocular tumors reside in an immune-privileged site, yet in certain circumstances, they can undergo immune rejection. Ocular tumor rejection can follow one of two pathways. One pathway is CD4+ T cell-dependent and culminates in ischemic necrosis of the tumor and phthisis (atrophy) of the eye. A second pathway is also CD4+ T cell-dependent but does not inflict collateral injury to ocular tissues, and the eye is preserved. We isolated two clones of a murine tumor, Ad5E1 that undergo profoundly different forms of immune rejection in the eye. Clone 2.1 tumors undergo an ischemic necrotizing form of rejection that requires IFN-γ, T cells, and ocular macrophages and culminates in destruction of the eye. By contrast, the second clone of Ad5E1, clone 4, undergoes rejection that also requires T cells and ocular macrophages, but leaves the eye in pristine condition (nonphthisical rejection). Here, we demonstrate that nonphthisical tumor rejection of clone 4 tumors is IFN-γ-independent but requires an ocular macrophage population that contains M1 and M2 macrophages. Clone 4 tumor-bearing eyes displayed ten- and 15-fold increases in M2- and M1-associated markers Arg1 and NO2, respectively. This is in sharp contrast to previous results with clone 2.1 tumor rejection, in which M2 markers were undetectable, and the eye was destroyed. These results suggest that the presence of M2 macrophages tempers the immune rejection of intraocular tumors and promotes immune effectors that inflict minimal injury to innocent bystander cells and thereby preserve the integrity and function of the eye. PMID:22693246

  5. Three-Dimensional Microfluidic Collagen Hydrogels for Investigating Flow-Mediated Tumor-Endothelial Signaling and Vascular Organization

    PubMed Central

    Voigt, Elizabeth E.; Szot, Christopher S.; Freeman, Joseph W.; Vlachos, Pavlos P.; Rylander, Marissa Nichole

    2014-01-01

    Hyperpermeable tumor vessels are responsible for elevated interstitial fluid pressure and altered flow patterns within the tumor microenvironment. These aberrant hydrodynamic stresses may enhance tumor development by stimulating the angiogenic activity of endothelial cells lining the tumor vasculature. However, it is currently not known to what extent shear forces affect endothelial organization or paracrine signaling during tumor angiogenesis. The objective of this study was to develop a three-dimensional (3D), in vitro microfluidic tumor vascular model for coculture of tumor and endothelial cells under varying flow shear stress conditions. A central microchannel embedded within a collagen hydrogel functions as a single neovessel through which tumor-relevant hydrodynamic stresses are introduced and quantified using microparticle image velocimetry (μ-PIV). This is the first use of μ-PIV in a tumor representative, 3D collagen matrix comprised of cylindrical microchannels, rather than planar geometries, to experimentally measure flow velocity and shear stress. Results demonstrate that endothelial cells develop a confluent endothelium on the microchannel lumen that maintains integrity under physiological flow shear stresses. Furthermore, this system provides downstream molecular analysis capability, as demonstrated by quantitative RT-PCR, in which, tumor cells significantly increase expression of proangiogenic genes in response to coculture with endothelial cells under low flow conditions. This work demonstrates that the microfluidic in vitro cell culture model can withstand a range of physiological flow rates and permit quantitative measurement of wall shear stress at the fluid–collagen interface using μ-PIV optical flow diagnostics, ultimately serving as a versatile platform for elucidating the role of fluid forces on tumor–endothelial cross talk. PMID:23730946

  6. Ecto-5′-Nucleotidase (CD73)-Mediated Formation of Adenosine Is Critical for the Striatal Adenosine A2A Receptor Functions

    PubMed Central

    Augusto, Elisabete; Matos, Marco; Sévigny, Jean; El-Tayeb, Ali; Bynoe, Margaret S.; Müller, Christa E.

    2013-01-01

    Adenosine is a neuromodulator acting through inhibitory A1 receptors (A1Rs) and facilitatory A2ARs, which have similar affinities for adenosine. It has been shown that the activity of intracellular adenosine kinase preferentially controls the activation of A1Rs, but the source of the adenosine activating A2ARs is unknown. We now show that ecto-5′-nucleotidase (CD73), the major enzyme able to convert extracellular AMP into adenosine, colocalizes with A2ARs in the basal ganglia. In addition to astrocytes, striatal CD73 is prominently localized to postsynaptic sites. Notably, CD73 coimmunoprecipitated with A2ARs and proximity ligation assays confirmed the close proximity of CD73 and A2ARs in the striatum. Accordingly, the cAMP formation in synaptosomes as well as the hypolocomotion induced by a novel A2AR prodrug that requires CD73 metabolization to activate A2ARs were observed in wild-type mice, but not in CD73 knock-out (KO) mice or A2AR KO mice. Moreover, CD73 KO mice displayed increased working memory performance and a blunted amphetamine-induced sensitization, mimicking the phenotype of global or forebrain-A2AR KO mice, as well as upon pharmacological A2AR blockade. These results show that CD73-mediated formation of extracellular adenosine is responsible for the activation of striatal A2AR function. This study points to CD73 as a new target that can fine-tune A2AR activity, and a novel therapeutic target to manipulate A2AR-mediated control of striatal function and neurodegeneration. PMID:23843511

  7. The YAP1/SIX2 axis is required for DDX3-mediated tumor aggressiveness and cetuximab resistance in KRAS-wild-type colorectal cancer

    PubMed Central

    Wu, De-Wei; Lin, Po-Lin; Wang, Lee; Huang, Chi-Chou; Lee, Huei

    2017-01-01

    The mechanism underlying tumor aggressiveness and cetuximab (CTX) resistance in KRAS-wild-type (KRAS -WT) colorectal cancer remains obscure. We here provide evidence that DDX3 promoted soft agar growth and invasiveness of KRAS-WT cells, as already confirmed in KRAS-mutated cells. Mechanistically, increased KRAS expression induced ROS production, which elevated HIF-1α and YAP1 expression. Increased HIF-1α persistently promoted DDX3 expression via a KRAS/ROS/HIF-1α feedback loop. DDX3-mediated aggressiveness and CTX resistance were regulated by the YAP1/SIX2 axis in KRAS-WT cells and further confirmed in animal models. Kaplan-Meier and Cox regression analysis indicated that DDX3, KRAS, and YAP1 expression had prognostic value for OS and RFS in KRAS-WT and KRAS-mutated tumors, but SIX2 and YAP1/SIX2 were prognostic value only in KRAS-WT patients. The observation from patients seemed to support the mechanistic action of cell and animal models. We therefore suggest that combining YAP1 inhibitors with CTX may therefore suppress DDX3-mediated tumor aggressiveness and enhance CTX sensitivity in KRAS-WT colorectal cancer. PMID:28435452

  8. Acquisition of tumor cell phenotypic diversity along the EMT spectrum under hypoxic pressure: Consequences on susceptibility to cell-mediated cytotoxicity.

    PubMed

    Terry, Stéphane; Buart, Stéphanie; Tan, Tuan Zea; Gros, Gwendoline; Noman, Muhammad Zaeem; Lorens, James B; Mami-Chouaib, Fathia; Thiery, Jean Paul; Chouaib, Salem

    2017-01-01

    Tumor escape to immunosurveillance and resistance to immune attacks present a major hurdle in cancer therapy, especially in the current era of new cancer immunotherapies. We report here that hypoxia, a hallmark of most solid tumors, orchestrates carcinoma cell heterogeneity through the induction of phenotypic diversity and the acquisition of distinct epithelial-mesenchymal transition (EMT) states. Using lung adenocarcinoma cells derived from a non-metastatic patient, we demonstrated that hypoxic stress induced phenotypic diversity along the EMT spectrum, with induction of EMT transcription factors (EMT-TFs) SNAI1, SNAI2, TWIST1, and ZEB2 in a hypoxia-inducible factor-1α (HIF1A)-dependent or -independent manner. Analysis of hypoxia-exposed tumor subclones, with pronounced epithelial or mesenchymal phenotypes, revealed that mesenchymal subclones exhibited an increased propensity to resist cytotoxic T lymphocytes (CTL), and natural killer (NK) cell-mediated lysis by a mechanism involving defective immune synapse signaling. Additionally, targeting EMT-TFs, or inhibition of TGF-β signaling, attenuated mesenchymal subclone susceptibility to immune attack. Together, these findings uncover hypoxia-induced EMT and heterogeneity as a novel driving escape mechanism to lymphocyte-mediated cytotoxicity, with the potential to provide new therapeutic opportunities for cancer patients.

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

    PubMed Central

    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

  10. Characterization of p53-mediated up-regulation of CD95 gene expression upon genotoxic treatment in human breast tumor cells.

    PubMed

    Ruiz-Ruiz, Carmen; Robledo, Gema; Cano, Eva; Redondo, Juan Miguel; Lopez-Rivas, Abelardo

    2003-08-22

    Death receptor CD95 gene expression is frequently low in human breast tumors and is up-regulated by genotoxic treatments in a p53-dependent manner. We have evaluated the relative contribution of promoter and intronic p53 consensus sites to the regulation of the human CD95 gene in breast tumor cells following doxorubicin treatment. Deletion constructs of the promoter region and site-directed mutagenesis of p53 consensus sites in a fragment spanning 1448 bp of the 5'-promoter demonstrate that these sites are not involved in the observed up-regulation of the CD95 gene upon doxorubicin treatment. In contrast, a p53 consensus site located within the first intron of CD95 gene is absolutely required for the inducible expression of CD95 upon genotoxic treatment in breast tumor cells. Analysis of the transcriptional activity of the two most common p53 mutants found in human breast tumors that are associated with resistance to doxorubicin reveals that these mutations completely eliminate the ability of p53 protein to transactivate CD95 gene expression. On the other hand, Bcl-2 overexpression albeit preventing doxorubicin-induced apoptosis, has no effect on p53-mediated CD95 up-regulation in breast tumor cells. Altogether, these results indicate the lack of involvement of p53 consensus sites of the CD95 promoter region and the pivotal role of intronic p53-responsive element in the regulation of human CD95 gene expression in breast tumor cells. Our results also suggest that in breast cancer patients with certain mutations in the p53 gene, expression of death receptor CD95 in response to genotoxic treatments could be severely compromised.

  11. Choindroitinase ABC I-Mediated Enhancement of Oncolytic Virus Spread and Anti Tumor Efficacy: A Mathematical Model

    PubMed Central

    Kim, Yangjin; Lee, Hyun Geun; Dmitrieva, Nina; Kim, Junseok; Kaur, Balveen; Friedman, Avner

    2014-01-01

    Oncolytic viruses are genetically engineered viruses that are designed to kill cancer cells while doing minimal damage to normal healthy tissue. After being injected into a tumor, they infect cancer cells, multiply inside them, and when a cancer cell is killed they move on to spread and infect other cancer cells. Chondroitinase ABC (Chase-ABC) is a bacterial enzyme that can remove a major glioma ECM component, chondroitin sulfate glycosoamino glycans from proteoglycans without any deleterious effects in vivo. It has been shown that Chase-ABC treatment is able to promote the spread of the viruses, increasing the efficacy of the viral treatment. In this paper we develop a mathematical model to investigate the effect of the Chase-ABC on the treatment of glioma by oncolytic viruses (OV). We show that the model's predictions agree with experimental results for a spherical glioma. We then use the model to test various treatment options in the heterogeneous microenvironment of the brain. The model predicts that separate injections of OV, one into the center of the tumor and another outside the tumor will result in better outcome than if the total injection is outside the tumor. In particular, the injection of the ECM-degrading enzyme (Chase-ABC) on the periphery of the main tumor core need to be administered in an optimal strategy in order to infect and eradicate the infiltrating glioma cells outside the tumor core in addition to proliferative cells in the bulk of tumor core. The model also predicts that the size of tumor satellites and distance between the primary tumor and multifocal/satellite lesions may be an important factor for the efficacy of the viral therapy with Chase treatment. PMID:25047810

  12. FasL Mediates T-Cell Eradication of Tumor Cells Presenting Low Levels of Antigens | Center for Cancer Research

    Cancer.gov

    One approach to cancer immunotherapy, as opposed to therapeutic vaccination, is the transfusion of large numbers of tumor-specific killer T cells (cytotoxic T cells or CTLs) into patients. The body’s own defense killer T cells are a subgroup of T lymphocytes (a type of white blood cells) that are capable of inducing death in tumor cells. CTLs can cause the death of target cells either by releasing granules containing toxic molecules including perforin, or by producing a membrane protein called Fas ligand (FasL) which on interaction with the tumor cell results in cell death.

  13. A marine sponge alkaloid derivative 4-chloro fascaplysin inhibits tumor growth and VEGF mediated angiogenesis by disrupting PI3K/Akt/mTOR signaling cascade.

    PubMed

    Sharma, Sonia; Guru, Santosh Kumar; Manda, Sudhakar; Kumar, Ashok; Mintoo, Mubashir J; Prasad, Venna Deva; Sharma, Parduman R; Mondhe, Dilip M; Bharate, Sandip B; Bhushan, Shashi

    2017-09-25

    Tumor angiogenesis and PI3K/Akt/mTOR pathway are two major molecular objectives for the treatment and management of breast cancer. Here we first time report the molecular mechanism of a marine sponge alkaloid derivative 4-chloro fascapysin (4-CF) for its anticancer and antiangiogenesis potential. It simultaneously targets multiple cancer and angiogenesis dynamics, such as proliferation, chemotaxis cell migration, and invasion, growth factors signaling cascade, autophagy and apoptosis in HUVEC and MDAMB-231 breast cancer cells. It inhibited the VEGF mediated microvessel sprouting and blood vessel formation in the matrigel plug of C57/BL6J mice. It inhibits the tumor growth in ET (solid) mouse tumor model. It significantly inhibited cell survival through PI3K/Akt/mTOR pathway, with attendant effects on key pro-angiogenesis factors like HIF-1α, eNOS and MMP-2/9. The cytotoxicity of 4-CF was reversed by co-treatment with the VEGF and Akt inhibitors sunitinib and perifosine, respectively or by the addition of neutralizing VEGF antibodies. The apoptotic potential of 4-CF was through mitochondrial dependent as illustrated through loss of mitochondrial membrane potential. The safety profile of 4-CF was acceptable as it exhibits five times high cytotoxic IC50 value in normal cells as well as no apparent toxicities in experimental tumor mice at therapeutic doses. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Mapping a functional cancer genome atlas of tumor suppressors in mouse liver using AAV-CRISPR–mediated direct in vivo screening

    PubMed Central

    Wang, Guangchuan; Chow, Ryan D.; Ye, Lupeng; Guzman, Christopher D.; Dai, Xiaoyun; Dong, Matthew B.; Zhang, Feng; Sharp, Phillip A.; Platt, Randall J.; Chen, Sidi

    2018-01-01

    Cancer genomics consortia have charted the landscapes of numerous human cancers. Whereas some mutations were found in classical oncogenes and tumor suppressors, others have not yet been functionally studied in vivo. To date, a comprehensive assessment of how these genes influence oncogenesis is lacking. We performed direct high-throughput in vivo mapping of functional variants in an autochthonous mouse model of cancer. Using adeno-associated viruses (AAVs) carrying a single-guide RNA (sgRNA) library targeting putative tumor suppressor genes significantly mutated in human cancers, we directly pool-mutagenized the livers of Cre-inducible CRISPR (clustered regularly interspaced short palindromic repeats)–associated protein 9 (Cas9) mice. All mice that received the AAV-mTSG library developed liver cancer and died within 4 months. We used molecular inversion probe sequencing of the sgRNA target sites to chart the mutational landscape of these tumors, revealing the functional consequence of multiple variants in driving liver tumorigenesis in immunocompetent mice. AAV-mediated autochthonous CRISPR screens provide a powerful means for mapping a provisional functional cancer genome atlas of tumor suppressors in vivo. PMID:29503867

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

    SciTech Connect

    Yu, Zhendong, E-mail: zdyu@hotmail.com; Wang, Hao; Zhang, Libin

    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/prodrugmore » system.« less

  16. Synergistic roles of granzymes A and B in mediating target cell death by rat basophilic leukemia mast cell tumors also expressing cytolysin/perforin

    PubMed Central

    1995-01-01

    We have studied the cytotoxic activity of rat basophilic leukemia (RBL) cells transfected with cDNAs for the cytotoxic T lymphocyte (CTL) granule components, cytolysin (perforin), granzyme A, and granzyme B. With red cell targets, cytolysin expression conferred potent hemolytic activity, which was not influenced by coexpression of granzymes. With tumor targets, RBL cells expressing cytolysin alone were weakly cytotoxic, but both cytolytic and nucleolytic activity were enhanced by coexpression of granzyme B. RBL cells expressing all three CTL granule components showed still higher cytotoxic activities, with apoptotic target death. Analysis of the cytotoxic activity of individual transfectant clones showed that cytolytic and nucleolytic activity correlated with granzyme expression but was independent of cytolysin expression within the range examined. A synergism between granzymes A and B was apparent when the triple transfectant was compared with RBL cells expressing cytolysin and one granzyme. These data implicate granzymes as the major mediators of tumor target damage by cytotoxic lymphocytes. PMID:7869027

  17. Composition of PLGA and PEI/DNA nanoparticles improves ultrasound-mediated gene delivery in solid tumors in vivo.

    PubMed

    Chumakova, Olga V; Liopo, Anton V; Andreev, Valery G; Cicenaite, Inga; Evers, B Mark; Chakrabarty, Shilla; Pappas, Todd C; Esenaliev, Rinat O

    2008-03-18

    The goal of this study was to enhance gene delivery and tumor cell transfection in vivo by using a combination of ultrasonication with complex nanoparticles consisting of two types of nanoparticles: PEI/DNA beta-gal plasmid with highly positive zeta-potential and air-filled poly (lactic-co-glycolic acid) (PLGA) particles (with negative zeta-potential) manufactured in our laboratory. The PLGA/PEI/DNA nanoparticles were a colloid with positive zeta-potential and injected i.v. in nude mice with DU145 human prostate tumors. We found that the combination of PLGA/PEI/DNA nanoparticles with ultrasonication substantially enhanced tumor cell transfection in vivo. The overexpression of beta-gal gene was evaluated histochemically and by Western blot analysis. At least an 8-fold increase of the cell transfection efficacy was obtained in irradiated tumors compared to non-irradiated controls, while little to no cell death was produced by ultrasonication.

  18. The tumor suppressors p33ING1 and p33ING2 interact with alien in vivo and enhance alien-mediated gene silencing.

    PubMed

    Fegers, Inga; Kob, Robert; Eckey, Maren; Schmidt, Oliver; Goeman, Frauke; Papaioannou, Maria; Escher, Niko; von Eggeling, Ferdinand; Melle, Christian; Baniahmad, Aria

    2007-11-01

    The tumor suppressor p33ING1 is involved in DNA repair and cell cycle regulation. Furthermore, p33ING1 is a transcriptional silencer that recognizes the histone mark for trimethylated lysine 4 at histone H3. Interestingly, expression of p33ING1 and p33ING2 is able to induce premature senescence in primary human fibroblasts. The corepressor Alien is involved in gene silencing mediated by selected members of nuclear hormone receptors. In addition, Alien acts as a corepressor for E2F1, a member of the E2F cell cycle regulatory family. Furthermore, recent findings suggest that Alien is complexed with transcription factors participating in DNA repair and chromatin. Here, using a proteomic approach by surface-enhanced laser desorption ionization and mass spectrometry (SELDI-MS) combined with immunological techniques, we show that Alien interacts in vivo with the tumor suppressor p33ING1 as well as with the related tumor suppressor candidate p33ING2. The interaction of Alien with p33ING1 and p33ING2 was confirmed in vitro with GST-pull-down, suggesting a direct binding of Alien to these factors. The binding domain was mapped to a central region of Alien. Functionally, the expression of p33ING1 or p33ING2 enhances the Alien-mediated silencing, suggesting that the interaction plays a role in transcriptional regulation. Thus, the findings suggest that the identified interaction between Alien and the tumor suppressors p33ING1 and p33ING2 reveals a novel cellular protein network.

  19. Survival of residual neutrophils and accelerated myelopoiesis limit the efficacy of antibody-mediated depletion of Ly-6G+ cells in tumor-bearing mice.

    PubMed

    Moses, Katrin; Klein, Johanna C; Männ, Linda; Klingberg, Anika; Gunzer, Matthias; Brandau, Sven

    2016-06-01

    Expansion of Ly-6G(+) myeloid cells has been reported in most murine cancer models. However, divergent findings exist regarding the role and effect of these cells on host immunity and tumor progression. Antibody-mediated depletion of Ly-6G(+) cells is a common technique to assess the in vivo relevance of these cells. Interpretation of results crucially depends on the efficacy and course of depletion. We established murine head and neck cancer models and analyzed the efficacy of antibody-mediated depletion by flow cytometry, conventional histology, and intravital imaging with a novel Ly-6G-transgenic mouse model. The first phase of depletion was characterized by effective elimination of Ly-6G(+) cells from the peripheral blood. Nevertheless, viable, resistant cells were found to reside in the tumor tissue and spleen. This peripheral depletion phase was associated with high systemic levels of granulocyte colony-stimulating factor and KC and enhanced splenic production of Ly-6G(+) cells. Even under sustained treatment with either αGr-1 or αLy-6G antibodies, peripheral blood depletion ended after approximately 1 wk and was followed by reappearance of immature Ly-6G(+) cells with an immunoregulatory phenotype. Reappearance of these depletion-resistant immature cells was enhanced in tumor-bearing, compared with naïve, control mice. Collectively, our data suggest that depletion of Ly-6G(+) myeloid cells in tumor-bearing mice is counteracted by the persistence of intratumoral cells, enhanced extramedullary granulopoiesis, and accelerated reappearance of immature cells. Hence, extensive monitoring of in vivo kinetics and tissue distribution of Ly-6G(+) cells is required in depletion studies. © Society for Leukocyte Biology.

  20. Genetic and Methylation-Induced Loss of miR-181a2/181b2 within chr9q33.3 Facilitates Tumor Growth of Cervical Cancer through the PIK3R3/Akt/FoxO Signaling Pathway.

    PubMed

    Mei, Qian; Li, Xiang; Zhang, Kang; Wu, Zhiqiang; Li, Xiaolei; Meng, Yuanguang; Guo, Mingzhou; Luo, Guangbin; Fu, Xiaobing; Han, Weidong

    2017-01-15

    Loss of Chr9q31-33 is one of the most common chromosome imbalances of cervical cancer, but the underlying mechanism has not been well documented. The loss of heterozygosity (LOH) status of Chr9q31-33 was investigated utilizing 26 microsatellite markers. We detected the expression of miR-181a2/181b2 by qRT-PCR analysis of cervical cancer cell lines and 100 paired tumor samples and corresponding adjacent non-tumor tissues. Kaplan-Meier and Cox proportional hazard regression analyses were performed to identify the prognostic value of miR-181a2/181b2. Regulation of expression was analyzed by methylation-specific PCR. The tumor-suppressing effects of miR-181a2/181b2 were determined in vitro and in vivo The target gene and signaling pathway that mediated the function of miR-181a2/181b2 were also identified. Chr9q33.3 was identified as one of the most deleted regions in cervical cancer. Underexpression of miR-181a2/181b2 was detected in 46% of cervical cancer and was induced by the LOH of chr9q33.3 and promoter hypermethylation. Attenuated miR-181a2/181b2 expression predicted a poor prognostic phenotype and advanced clinical stage of cervical cancer. miR-181a2/181b2 prominently dampened cell-cycle progression, suppressed cell growth, and promoted apoptosis of tumor cells in vitro They also effectively impeded tumor formation and growth in vivo miR-181a2/181b2 exert the tumor suppressor ability by depressing the direct target PIK3R3 (p55γ) and consequently modulating the PIK3R3/Akt/FoxO signaling pathway. We demonstrated a cause-and-effect event beginning from loss of chr9q33.3, a frequent event in cervical cancer, to the underexpression of miR-181a2/181b2, leading to the elevated activation of the PI3K pathway. Clin Cancer Res; 23(2); 575-86. ©2016 AACR. ©2016 American Association for Cancer Research.

  1. Self-Assembly of Gold Nanoparticles Shows Microenvironment-Mediated Dynamic Switching and Enhanced Brain Tumor Targeting.

    PubMed

    Feng, Qishuai; Shen, Yajing; Fu, Yingjie; Muroski, Megan E; Zhang, Peng; Wang, Qiaoyue; Xu, Chang; Lesniak, Maciej S; Li, Gang; Cheng, Yu

    2017-01-01

    Inorganic nanoparticles with unique physical properties have been explored as nanomedicines for brain tumor treatment. However, the clinical applications of the inorganic formulations are often hindered by the biological barriers and failure to be bioeliminated. The size of the nanoparticle is an essential design parameter which plays a significant role to affect the tumor targeting and biodistribution. Here, we report a feasible approach for the assembly of gold nanoparticles into ~80 nm nanospheres as a drug delivery platform for enhanced retention in brain tumors with the ability to be dynamically switched into the single formulation for excretion. These nanoassemblies can target epidermal growth factor receptors on cancer cells and are responsive to tumor microenvironmental characteristics, including high vascular permeability and acidic and redox conditions. Anticancer drug release was controlled by a pH-responsive mechanism. Intracellular L-glutathione (GSH) triggered the complete breakdown of nanoassemblies to single gold nanoparticles. Furthermore, in vivo studies have shown that nanospheres display enhanced tumor-targeting efficiency and therapeutic effects relative to single-nanoparticle formulations. Hence, gold nanoassemblies present an effective targeting strategy for brain tumor treatment.

  2. Inflammatory myofibroblastic tumors of the lung carrying a chimeric A2M-ALK gene: report of 2 infantile cases and review of the differential diagnosis of infantile pulmonary lesions.

    PubMed

    Tanaka, Mio; Kohashi, Kenichi; Kushitani, Kei; Yoshida, Misa; Kurihara, Sho; Kawashima, Masumi; Ueda, Yuka; Souzaki, Ryota; Kinoshita, Yoshiaki; Oda, Yoshinao; Takeshima, Yukio; Hiyama, Eiso; Taguchi, Tomoaki; Tanaka, Yukichi

    2017-08-01

    We report 2 infantile cases of pulmonary tumor carrying a chimeric A2M-ALK gene. A2M-ALK is a newly identified anaplastic lymphoma kinase (ALK)-related chimeric gene from a tumor diagnosed as fetal lung interstitial tumor (FLIT). FLIT is a recently recognized infantile pulmonary lesion defined as a mass-like lesion that morphologically resembles the fetal lung. Grossly, FLIT characteristically appears as a well-circumscribed spongy mass, whereas the tumors in these patients were solid and firm. Histologically, the tumors showed intrapulmonary lesions composed of densely proliferating polygonal or spindle-shaped mesenchymal cells with diffuse and dense infiltrations of inflammatory cells forming microcystic or micropapillary structures lined by thyroid transcription factor 1-positive pneumocytes, favoring inflammatory myofibroblastic tumor rather than FLIT. The proliferating cells were immunoreactive for ALK, and A2M-ALK was identified in both tumors with reverse-transcription polymerase chain reaction. The dense infiltration of inflammatory cells, immunoreactivity for ALK, and identification of an ALK-related chimeric gene suggested a diagnosis of inflammatory myofibroblastic tumor. Histologically, most reported FLITs show sparse inflammatory infiltrates and a relatively low density of interstitial cells in the septa, although prominent infiltration of inflammatory cells and high cellularity of interstitial cells are seen in some FLITs. The present cases suggest that ALK rearrangements, including the chimeric A2M-ALK gene, may be present in these infantile pulmonary lesions, especially those with inflammatory cell infiltration. We propose that these infantile pulmonary lesions containing a chimeric A2M-ALK gene be categorized as a specific type of inflammatory myofibroblastic tumor that develops exclusively in neonates and infants. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Interplay among Drosophila transcription factors Ets21c, Fos and Ftz-F1 drives JNK-mediated tumor malignancy

    PubMed Central

    Külshammer, Eva; Mundorf, Juliane; Kilinc, Merve; Frommolt, Peter; Wagle, Prerana; Uhlirova, Mirka

    2015-01-01

    ABSTRACT 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 study

  4. Metformin can block precancerous progression to invasive tumors of bladder through inhibiting STAT3-mediated signaling pathways.

    PubMed

    Pan, Qi; Yang, Guo-Liang; Yang, Jiang-Hua; Lin, Shi-Long; Liu, Ning; Liu, Shan-Shan; Liu, Meng-Yao; Zhang, Lian-Hua; Huang, Yi-Ran; Shen, Ru-long; Liu, Qiang; Gao, Jian-Xin; Bo, Juan-Jie

    2015-08-07

    Metformin is the first line of oral antidiabetic drug in the biguanide class for treatment of type 2 diabetes. Increasing evidence has suggested that it is a potential anti-tumor drug. However, the mechanisms underlying inhibiting tumor development remain elusive, especially in bladder tumors. T24 and J82 cell lines were used as an in vitro model, and 24 female SD rats were used to build an N-methyl-N-nitrosourea (MNU)-induced orthotopic rat bladder cancer model. Transfection of lentivirus-based shRNA was used to construct the STAT3-KNOCKDOWN T24 cell line. After metformin treatment, the viability of bladde cancer cells was determined by CCK8. Cell cycle distribution and apoptosis were assessed by flow cytometry. The migration and invasion abilities of cells were evaluated by wound healing and transwell asssays. The inactivation of stat3 pahtway was examined by qRTPCR, western blot and Immunofluorescence. Metformin can effectively inhibit precancerous progression to invasive cancer in an MNU-induced rat orthotopic bladder tumor model, although it could not completely suppress normal cells transforming into tumor cells. While the MNU could induce 50 % rats (4/8) to develop invasive bladder cancers, the rats co-administrated with metformin failed to develop invasive tumors but retained at precancerous or non-invasive stages, exhibiting as dysplasia, papillary tumor and/or carcinoma in situ (CIS). Accordingly, phosphorylation of signal transducer and activator of transcription 3 (STAT3), which is a well known oncogene, was significantly inhibited in the tumors of rats treated with metformin. In vitro experiments revealed that the metformin could efficiently inhibit STAT3 activation, which was associated with the cell cycle arrest, reduction of cell proliferation, migration and invasiveness, and increase in apoptotic cell death of bladder cancer cell lines. These findings provide for the first time the evidence that metformin can block precancerous lesions progressing

  5. Disruption of the GluA2/GAPDH complex using TAT-GluA2NT1-3-2 peptide protects against AMPAR-mediated excitotoxicity after epilepsy.

    PubMed

    Zhang, Jinghui; Qiao, Nana; Ding, Xiufang; Wang, Jiwen

    2018-03-21

    Excitotoxicity and neuronal death following epilepsy involve α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs). It forms a protein complex with glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and co-internalizes upon activation of AMPA receptors after epilepsy. Disruption of the GluA2/GAPDH complex with an interfering peptide, TAT-GluA2NT1-3-2, protects cells against AMPAR-mediated excitotoxicity, which have been identified in in-vitro and in-vivo models of brain ischemia. We postulated that disruption of the GluA2/GAPDH interaction with the TAT-GluA2NT1-3-2 peptide would also protect against AMPAR-induced neuronal injury in an in-vivo model of status epilepticus (SE). In the present study, we divided pilocarpine-induced SE Wistar rats into three main groups: the TAT-GluA2NT1-3-2 peptide group, the TAT-GluA2NT-scram peptide group, and the normal saline group, and injected different doses of peptides stereotaxically into the hippocampus of SE rats to investigate whether the GluA2/GAPDH interaction could be disrupted by our TAT-GluA2NT1-3-2 peptide and determine its most appropriate dose. Then, the dose was administered stereotaxically at different time points after SE to determine the best administration time of neuronal protection. We found that the TAT-GluA2NT1-3-2 peptide can disrupt the GluA2/GAPDH interaction and protects against epilepsy-induced neuronal damage. The GluA2/GAPDH interaction may be a novel therapeutic target for epilepsy.

  6. EphrinA1 inhibits malignant mesothelioma tumor growth via let-7 microRNA-mediated repression of the RAS oncogene.

    PubMed

    Khodayari, N; Mohammed, K A; Goldberg, E P; Nasreen, N

    2011-11-01

    EphrinA1 binding with receptor EphA2 suppresses malignant mesothelioma (MM) growth. The mechanisms whereby EphrinA1 attenuates the MM cell (MMC) growth are not clear. In this study, we report that the activation of MMCs with EphrinA1 leads to an induction of let-7 microRNA (miRNA) expression, repression of RAS proto-oncogene and the attenuation of MM tumor growth. The expression of miRNAs was determined by reverse transcription-quantitative polymerase chain reaction and in situ hybridization. RAS expression was determined by q-PCR, western blotting and immunofluorescence. MMC proliferation and tumor growth were determined by WST-1 and Matrigel assay, respectively. EphrinA1 activation induced several fold increases in let-7a1, let-7a3, let-7f1 and let-7f2 miRNA expression in MMCs. In contrast, EphrinA1 activation significantly downregulated H-RAS, K-RAS and N-RAS expression and inhibited MMC proliferation and tumor growth. In MMCs transfected with 2'-O-methyl antisense oligonucleotides to let-7 miRNA, EphrinA1 activation failed to inhibit the proliferative response and tumor growth. In mismatch antisense oligonucleotide-treated MMCs, the proliferation and tumor growth were comparable to untreated proliferating cells. Furthermore, the transfection of MMCs with let-7a miRNA precursor inhibited RAS expression and attenuated MMC tumor growth. Our data revealed that EphrinA1 signaling induces let-7 miRNA expression and attenuates MM tumor growth by targeting RAS proto-oncogene in MMCs.

  7. A Copper-Mediated Disulfiram-Loaded pH-Triggered PEG-Shedding TAT Peptide-Modified Lipid Nanocapsules for Use in Tumor Therapy.

    PubMed

    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.

  8. The effects of RNA interference mediated VEGF gene silencing on biological behavior of renal cell carcinoma and transplanted renal tumor in nude mice.

    PubMed

    Wang, Qi; Wang, Shuai; Sun, Si-Qiao; Cheng, Zhi-Hua; Zhang, Yang; Chen, Guang; Gu, Meng; Yao, Hai-Jun; Wang, Zhong; Zhou, Juan; Peng, Yu-Bing; Xu, Ming-Xi; Zhang, Ke; Sun, Xi-Wei

    2016-01-01

    This study was to explore the effects of RNA interference mediated vascular endothelial growth factor (VEGF) gene silencing on biological behavior of renal cell carcinoma (RCC), transplanted renal tumor and angiogenesis in nude mice. The specific siRNA sequence targeting VEGF were designed and synthesized to construct hVEGF-siRNA plasmid which was transfected into RCC 786-O cells. Reverse transcriptase-polymerase chain reaction (RT-PCR) was used for the detection of VEGF gene expression and western blot was adopted for the examination of VEGF protein expression. The 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to detect cell growth as well as cell migration and invasion. The transplanted renal tumor models in nude mice were established, and the growth condition of nude mice, and VEGF protein expression in transplanted tumor slices and the microvessel density (MVD) were detected. The expression level of VEGF mRNA in VEGF-siRNA group was significant lower than that in the control group and negative group, suggesting that establishment of plasmid specifically inhibited the expression of VEGF gene The expression level of VEGF protein in VEGF-siRNA group was significant lower than that in the control group and negative group. VEGF gene silencing has the significant inhibition effects on proliferation, migration and invasion of RCC 786-O cells. The tumor weight, VEGF protein positive rate and MVD in VEGF-siRNA group were significant lower than those in negative group and blank group. The VEGF gene silencing could inhibit the cell proliferation, migration and invasion of RCC 786-O cells; inhibition of VEGF protein expression could prevent transplanted RCC growth and tumor angiogenesis.

  9. Tumor cells switch to mitochondrial oxidative phosphorylation under radiation via mTOR-mediated hexokinase II inhibition--a Warburg-reversing effect.

    PubMed

    Lu, Chung-Ling; Qin, Lili; Liu, Hsin-Chen; Candas, Demet; Fan, Ming; Li, Jian Jian

    2015-01-01

    A unique feature of cancer cells is to convert glucose into lactate to produce cellular energy, even under the presence of oxygen. Called aerobic glycolysis [The Warburg Effect] it has been extensively studied and the concept of aerobic glycolysis in tumor cells is generally accepted. However, it is not clear if aerobic glycolysis in tumor cells is fixed, or can be reversed, especially under therapeutic stress conditions. Here, we report that mTOR, a critical regulator in cell proliferation, can be relocated to mitochondria, and as a result, enhances oxidative phosphorylation and reduces glycolysis. Three tumor cell lines (breast cancer MCF-7, colon cancer HCT116 and glioblastoma U87) showed a quick relocation of mTOR to mitochondria after irradiation with a single dose 5 Gy, which was companied with decreased lactate production, increased mitochondrial ATP generation and oxygen consumption. Inhibition of mTOR by rapamycin blocked radiation-induced mTOR mitochondrial relocation and the shift of glycolysis to mitochondrial respiration, and reduced the clonogenic survival. In irradiated cells, mTOR formed a complex with Hexokinase II [HK II], a key mitochondrial protein in regulation of glycolysis, causing reduced HK II enzymatic activity. These results support a novel mechanism by which tumor cells can quickly adapt to genotoxic conditions via mTOR-mediated reprogramming of bioenergetics from predominantly aerobic glycolysis to mitochondrial oxidative phosphorylation. Such a "waking-up" pathway for mitochondrial bioenergetics demonstrates a flexible feature in the energy metabolism of cancer cells, and may be required for additional cellular energy consumption for damage repair and survival. Thus, the reversible cellular energy metabolisms should be considered in blocking tumor metabolism and may be targeted to sensitize them in anti-cancer therapy.

  10. Small interfering RNA-mediated reduction in heterogeneous nuclear ribonucleoparticule A1/A2 proteins induces apoptosis in human cancer cells but not in normal mortal cell lines.

    PubMed

    Patry, Caroline; Bouchard, Louise; Labrecque, Pascale; Gendron, Daniel; Lemieux, Bruno; Toutant, Johanne; Lapointe, Elvy; Wellinger, Raymund; Chabot, Benoit

    2003-11-15

    To prevent their recognition as DNA breaks, the ends of linear chromosomes are organized into telomeres, which are made of proteins bound to telomere-specific, double-stranded repeats and to single-stranded DNA extensions, the G-tails. The mammalian heterogeneous nuclear ribonucleoparticule A1 and A2 proteins can bind with high affinity to such G-tails. Moreover, previous work established that in certain mouse cells a severe reduction in the level of A1 is associated with shortened telomeric repeat tracts, and restoring A1 expression increases telomere length. Here, we document that the expression of A1/A2 proteins is elevated in a variety of human cancers, whereas A1/A2 expression is lower or absent in normal tissues. To determine whether the status of A1/A2 proteins could be improved from cancer markers to cancer targets, we used small interfering RNA-mediated RNA interference to elicit a reduction in A1/A2 proteins in a variety of human cell lines. We show that this treatment provoked specific and rapid cell death by apoptosis in cell lines derived from cervical, colon, breast, ovarian, and brain cancers. Cancer cell lines that lack p53 or express a defective p53 protein were equally sensitive to a small interfering RNA-mediated decrease in A1/A2 expression. The reduction in A1/A2 levels in HeLa cells was associated with a change in the distribution of the lengths of G-tails, an event not observed when apoptosis was induced with staurosporine. Remarkably, comparable decreases in the expression of A1/A2 in several mortal human fibroblastic and epithelial cell lines did not promote cell death. Thus, manipulating the level and activity of A1/A2 proteins may constitute a potent and specific approach in the treatment of human cancers of various origins.

  11. Roflumilast restores cAMP/PKA/CREB signaling axis for FtMt-mediated tumor inhibition of ovarian cancer.

    PubMed

    Gong, Shipeng; Chen, Yongning; Meng, Fanliang; Zhang, Yadi; Wu, Huan; Wu, Fei

    2017-12-22

    The abrogation of cAMP generation by overexpression of PDE isoforms promotes the inflammatory pathology, and the PDE inhibitors have showed the potential anti-inflammation effects in clinical. However, the function of PDE inhibitors in cancer treatment remains unclear. We here investigated the role of PDE4 inhibitor Roflumilast in the treatment of ovarian cancer. We found that Roflumilast could effectively inhibit the proliferation, and induce apoptosis and cell cycle arrest in two ovarian cancer cell lines OVCAR3 and SKOV3. Meanwhile, the cAMP/PKA/CREB signals was activated by Roflumilast, which was accompanied by the up-regulation of mitochondrial ferritin (FtMt) level. Interestingly, forced expression of FtMt in ovarian cancer enhanced the apoptosis and inhibited tumor growth and the PKA inhibitor H89 and knockdown of CREB significantly repressed the expression of FtMt to restore the tumor proliferation and inhibit apoptosis. In addition, we found that Roflumilast-induced phosphorylated CREB directly promoted transcription of FtMt, indicating that Roflumilast up-regulated the expression of FtMt in ovarian cancer via cAMP/PKA/CREB signals. The anti-tumor role of Roflumilast in vivo was also demonstrated, the treatment of roflumilast effectively inhibited tumor proliferation and elevated the FtMt expression to restrict the tumor growth via the activation of cAMP/PKA/CREB signals in ovarian cancer.

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

    SciTech Connect

    Chung, Jin Sil; Lee, Sora; Yoo, Young Do, E-mail: ydy1130@korea.ac.kr

    2014-08-08

    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 nuclearmore » 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.« less

  13. The S100A10 subunit of the annexin A2 heterotetramer facilitates L2-mediated human papillomavirus infection.

    PubMed

    Woodham, Andrew W; Da Silva, Diane M; Skeate, Joseph G; Raff, Adam B; Ambroso, Mark R; Brand, Heike E; Isas, J Mario; Langen, Ralf; Kast, W Martin

    2012-01-01

    Mucosotropic, high-risk human papillomaviruses (HPV) are sexually transmitted viruses that are causally associated with the development of cervical cancer. The most common high-risk genotype, HPV16, is an obligatory intracellular virus that must gain entry into host epithelial cells and deliver its double stranded DNA to the nucleus. HPV capsid proteins play a vital role in these steps. Despite the critical nature of these capsid protein-host cell interactions, the precise cellular components necessary for HPV16 infection of epithelial cells remains unknown. Several neutralizing epitopes have been identified for the HPV16 L2 minor capsid protein that can inhibit infection after initial attachment of the virus to the cell surface, which suggests an L2-specific secondary receptor or cofactor is required for infection, but so far no specific L2-receptor has been identified. Here, we demonstrate that the annexin A2 heterotetramer (A2t) contributes to HPV16 infection and co-immunoprecipitates with HPV16 particles on the surface of epithelial cells in an L2-dependent manner. Inhibiting A2t with an endogenous annexin A2 ligand, secretory leukocyte protease inhibitor (SLPI), or with an annexin A2 antibody significantly reduces HPV16 infection. With electron paramagnetic resonance, we demonstrate that a previously identified neutralizing epitope of L2 (aa 108-120) specifically interacts with the S100A10 subunit of A2t. Additionally, mutation of this L2 region significantly reduces binding to A2t and HPV16 pseudovirus infection. Furthermore, downregulation of A2t with shRNA significantly decreases capsid internalization and infection by HPV16. Taken together, these findings indicate that A2t contributes to HPV16 internalization and infection of epithelial cells and this interaction is dependent on the presence of the L2 minor capsid protein.

  14. The S100A10 Subunit of the Annexin A2 Heterotetramer Facilitates L2-Mediated Human Papillomavirus Infection

    PubMed Central

    Woodham, Andrew W.; Da Silva, Diane M.; Skeate, Joseph G.; Raff, Adam B.; Ambroso, Mark R.; Brand, Heike E.; Isas, J. Mario; Langen, Ralf; Kast, W. Martin

    2012-01-01

    Mucosotropic, high-risk human papillomaviruses (HPV) are sexually transmitted viruses that are causally associated with the development of cervical cancer. The most common high-risk genotype, HPV16, is an obligatory intracellular virus that must gain entry into host epithelial cells and deliver its double stranded DNA to the nucleus. HPV capsid proteins play a vital role in these steps. Despite the critical nature of these capsid protein-host cell interactions, the precise cellular components necessary for HPV16 infection of epithelial cells remains unknown. Several neutralizing epitopes have been identified for the HPV16 L2 minor capsid protein that can inhibit infection after initial attachment of the virus to the cell surface, which suggests an L2-specific secondary receptor or cofactor is required for infection, but so far no specific L2-receptor has been identified. Here, we demonstrate that the annexin A2 heterotetramer (A2t) contributes to HPV16 infection and co-immunoprecipitates with HPV16 particles on the surface of epithelial cells in an L2-dependent manner. Inhibiting A2t with an endogenous annexin A2 ligand, secretory leukocyte protease inhibitor (SLPI), or with an annexin A2 antibody significantly reduces HPV16 infection. With electron paramagnetic resonance, we demonstrate that a previously identified neutralizing epitope of L2 (aa 108–120) specifically interacts with the S100A10 subunit of A2t. Additionally, mutation of this L2 region significantly reduces binding to A2t and HPV16 pseudovirus infection. Furthermore, downregulation of A2t with shRNA significantly decreases capsid internalization and infection by HPV16. Taken together, these findings indicate that A2t contributes to HPV16 internalization and infection of epithelial cells and this interaction is dependent on the presence of the L2 minor capsid protein. PMID:22927980

  15. Proapoptotic Protein Smac Mediates Apoptosis in Cisplatin-resistant Ovarian Cancer Cells When Treated with the Anti-tumor Agent AT101*

    PubMed Central

    Hu, Wenbin; Wang, Fang; Tang, Jingsheng; Liu, Xinyu; Yuan, Zhu; Nie, Chunlai; Wei, Yuquan

    2012-01-01

    Chemoresistance of ovarian cancer has been previously attributed to the expression and activation of Bcl-2 family proteins. BH3-mimetic molecules possessing potential anticancer activity are able to inhibit antiapoptotic Bcl-2 family proteins. AT101 (R-(−)-gossypol), a natural BH3-mimetic molecule, has shown anti-tumor activity as a single agent and in combination with standard anticancer therapies in a variety of tumor models. Here, we report the effect of AT101 on apoptosis in cisplatin-resistant ovarian cancer cells and identify the major molecular events that determine sensitivity. AT101 induced cell apoptosis by activating Bax through a conformational change, translocation, and oligomerization. The inhibition of Bax expression only partially prevented caspase-3 cleavage. However, the gene silencing of Bax had no effect on mitochondrial Smac release. Further experiments demonstrated that Smac reduction inhibited caspase-3 activation and attenuated cell apoptosis. More importantly, the inhibition of Smac or overexpression of XIAP attenuated Bax activation in ovarian cells. Furthermore, our data indicate that the Akt-p53 pathway is involved in the regulation of Smac release. Taken together, our data demonstrate the role of Smac and the molecular mechanisms of AT101-induced apoptosis of chemoresistant ovarian cancer cells. Our findings suggest that AT101 not only triggers Bax activation but also induces mitochondrial Smac release. Activated Smac can enhance Bax-mediated cellular apoptosis. Therefore, Smac mediates Bax activation to determine the threshold for overcoming cisplatin resistance in ovarian cancer cells. PMID:22052903

  16. Proapoptotic protein Smac mediates apoptosis in cisplatin-resistant ovarian cancer cells when treated with the anti-tumor agent AT101.

    PubMed

    Hu, Wenbin; Wang, Fang; Tang, Jingsheng; Liu, Xinyu; Yuan, Zhu; Nie, Chunlai; Wei, Yuquan

    2012-01-02

    Chemoresistance of ovarian cancer has been previously attributed to the expression and activation of Bcl-2 family proteins. BH3-mimetic molecules possessing potential anticancer activity are able to inhibit antiapoptotic Bcl-2 family proteins. AT101 (R-(-)-gossypol), a natural BH3-mimetic molecule, has shown anti-tumor activity as a single agent and in combination with standard anticancer therapies in a variety of tumor models. Here, we report the effect of AT101 on apoptosis in cisplatin-resistant ovarian cancer cells and identify the major molecular events that determine sensitivity. AT101 induced cell apoptosis by activating Bax through a conformational change, translocation, and oligomerization. The inhibition of Bax expression only partially prevented caspase-3 cleavage. However, the gene silencing of Bax had no effect on mitochondrial Smac release. Further experiments demonstrated that Smac reduction inhibited caspase-3 activation and attenuated cell apoptosis. More importantly, the inhibition of Smac or overexpression of XIAP attenuated Bax activation in ovarian cells. Furthermore, our data indicate that the Akt-p53 pathway is involved in the regulation of Smac release. Taken together, our data demonstrate the role of Smac and the molecular mechanisms of AT101-induced apoptosis of chemoresistant ovarian cancer cells. Our findings suggest that AT101 not only triggers Bax activation but also induces mitochondrial Smac release. Activated Smac can enhance Bax-mediated cellular apoptosis. Therefore, Smac mediates Bax activation to determine the threshold for overcoming cisplatin resistance in ovarian cancer cells.

  17. Scavenger receptor-mediated delivery of muramyl dipeptide activates antitumor efficacy of macrophages by enhanced secretion of tumor-suppressive cytokines.

    PubMed

    Srividya, S; Roy, R P; Basu, S K; Mukhopadhyay, A

    2000-05-01

    We showed that muramyl dipeptide (MDP) conjugated to maleylated bovine serum albumin (MBSA) was internalized by macrophages (Mphi) through scavenger receptor (SCR)-mediated endocytosis, which leads to 50-fold higher cytotoxic activity against non-Mphi tumor cells compared with that elicited by free MDP-treated Mphi. The enhanced cytotoxic effect of MBSA-MDP was found to be a result of higher secretion of interleukin (IL)-1, IL-6, tumor necrosis factor alpha (TNF-alpha), and nitric oxide (NO) because the addition of antibodies directed against IL-1, IL-6, or TNF-alpha in combination with Mphi cultures totally abrogated the tumoricidal activity of MBSA-MDP. It is interesting to note that MBSA-MDP triggers the secretion of IL-12, whereas IL-10, a Mphi suppressor cytokine, could be detected only on free MDP treatment. The cytotoxic activity of MBSA-MDP was inhibited by indomethacin, indicating a regulatory role for prostaglandin E2 (PGE2). Efficient SCR-mediated intracellular delivery of MDP leading to elimination of cancer cells suggests the immunotherapeutic potential of this approach for treatment of neoplasia.

  18. Enhanced anti-tumor activity by the combination of a conditionally replicating adenovirus mediated interleukin-24 and dacarbazine against melanoma cells via induction of apoptosis.

    PubMed

    Jiang, Guan; Liu, Yan-Qun; Wei, Zhi-Ping; Pei, Dong-Sheng; Mao, Li-Jun; Zheng, Jun-Nian

    2010-08-28

    Malignant melanoma is one of the most lethal and aggressive human malignancies. It is notoriously resistant to all of the current therapeutic modalities, including chemotherapy. Suppressed apoptosis and extraordinary invasiveness are the distinctive features that contribute to the malignancy of melanoma. Dacarbazine (DTIC) has been considered as the gold standard for melanoma treatment with a response rate of 15-20%. Unfortunately, the resistance to this chemotherapeutic agent occurs frequently. ZD55-IL-24 is a selective conditionally replicating adenovirus that can mediate the expression of interleukin-24 (IL-24) gene, which has a strong anti-tumor effect. In this study, we hypothesized that a combination of ZD55-IL-24-mediated gene virotherapy and chemotherapy using DTIC would produce an increased cytotoxicity against human melanoma cells in comparison with these agents alone. Our results showed that the combination of ZD55-IL-24 and DTIC significantly enhanced the anti-tumor activity by more effectively inducing apoptosis in melanoma cells than either agent used alone without any overlapping toxicity against normal cells. This additive or synergistic effect of ZD55-IL-24 in combination with DTIC in killing human malignant melanoma cells implies a promising novel approach for melanoma therapy. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

  19. Hemagglutinin protease secreted by V. cholerae induced apoptosis in breast cancer cells by ROS mediated intrinsic pathway and regresses tumor growth in mice model.

    PubMed

    Ray, Tanusree; Chakrabarti, Monoj Kumar; Pal, Amit

    2016-02-01

    Conventional anticancer therapies are effective but have side effects, so alternative targets are being developed. Bacterial toxins that can kill cells or alter the cellular processes like proliferation, apoptosis and differentiation have been reported for cancer treatment. In this study we have shown antitumor activity of hemagglutinin protease (HAP) secreted by Vibrio cholerae. One µg of HAP showed potent antitumor activity when injected into Ehrlich ascites carcinoma (EAC) tumors in Swiss albino mice. Weekly administration of this dose is able to significantly diminish a large tumor volume within 3 weeks and increases the survival rates of cancerous mice. HAP showed apoptotic activity on EAC and other malignant cells. Increased level of pro-apoptotic p53 with increased ratio of pro-apoptotic Bax to anti-apoptotic Bcl-2 signify that HAP induced apoptogenic signals lead to death of the tumor cells. In vivo and ex vivo studies suggest that mitochondrial dependent intrinsic pathway is responsible for this apoptosis. The level of ROS in malignant cells is reported to be higher than the normal healthy cells. HAP induces oxidative stress and increases the level of ROS in malignant cells which is significantly higher than the normal healthy cells. As a result the malignant cells cross the threshold level of ROS for cell survival faster than normal healthy cells. This mechanism causes HAP mediated apoptosis in malignant cells, but normal cells remain unaltered in the same environment. Our study suggests that HAP may be used as a new candidate drug for cancer therapy.

  20. Chlorella sorokiniana induces mitochondrial-mediated apoptosis in human non-small cell lung cancer cells and inhibits xenograft tumor growth in vivo.

    PubMed

    Lin, Ping-Yi; Tsai, Ching-Tsan; Chuang, Wan-Ling; Chao, Ya-Hsuan; Pan, I-Horng; Chen, Yu-Kuo; Lin, Chi-Chen; Wang, Bing-Yen

    2017-02-01

    Lung cancer is one of the leading causes of cancer related deaths worldwide. Marine microalgae are a source of biologically active compounds and are widely consumed as a nutritional supplement in East Asian countries. It has been reported that Chlorella or Chlorella extracts have various beneficial pharmacological compounds that modulate immune responses; however, no studies have investigated the anti-cancer effects of Chlorella sorokiniana (CS) on non-small cell lung cancer (NSCLC). In this study, we evaluated the anti-cancer effects of CS in two human NSCLC cell lines (A549 and CL1-5 human lung adenocarcinoma cells), and its effects on tumor growth in a subcutaneous xenograft tumor model. We also investigated the possible molecular mechanisms governing the pharmacological function of CS. Our results showed that exposure of the two cell lines to CS resulted in a concentration-dependent reduction in cell viability. In addition, the percentage of apoptotic cells increased in a dose-dependent manner, suggesting that CS might induce apoptosis in human NSCLC cells. Western blot analysis revealed that exposure to CS resulted in increased protein expression of the cleaved/activated forms of caspase-3, caspase-9, and PARP, except caspase-8. ZDEVD (caspase-3 inhibitor) and Z-LEHD (caspase-9 inhibitor) were sufficient at preventing apoptosis in both A549 and CL1-5 cells, proving that CS induced cell death via the mitochondria-mediated apoptotic pathway. Exposure of A549 and CL1-5 cells to CS for 24 h resulted in decreased expression of Bcl-2 protein and increased expression of Bax protein as well as decreased expression of two IAP family proteins, survivin and XIAP. We demonstrated that CS induces mitochondrial-mediated apoptosis in NSCLC cells via downregulation of Bcl-2, XIAP and survivin. In addition, we also found that the tumors growth of subcutaneous xenograft in vivo was markedly inhibited after oral intake of CS.

  1. Importance of the interaction between immune cells and tumor vasculature mediated by thalidomide in cancer treatment (Review).

    PubMed

    Wang, Xin; Shen, Yanwei; Li, Shuting; Lv, Meng; Zhang, Xiaoman; Yang, Jiao; Wang, Fan; Yang, Jin

    2016-10-01

    Over the past 60 years, thalidomide has metamorphosized from a drug prescribed to treat morning sickness in pregnant women, which was subsequently found to induce birth defects, into a highly effective therapy for treating leprosy and multiple myeloma. Several mechanisms have been proposed to explain the anticancer effects of thalidomide, including antiangiogenic and immunomodulatory activities. At present, evidence suggests that thalidomide may induce vessel maturation. Vascular normalization may be an effective strategy to enhance cancer immunotherapy. Numerous studies have shown that the tumor infiltrating immune cell subsets are important in regulating the process of tumor angiogenesis. The mechanisms associated with antiangiogenesis and the potent immunomodulatory effects of thalidomide obtained the most support. The studies of the antiangiogenic activity of thalidomide were guided in a novel direction by a hypothesis regarding the vascular normalization of tumors. Hence, thalidomide is effective in cancer treatment due to the interaction between immune cells and tumor vasculature. This mechanism provides new avenues to explore for the treatment of cancer.

  2. The role of slow and persistent TTX-resistant sodium currents in acute tumor necrosis factor-α-mediated increase in nociceptors excitability

    PubMed Central

    Gudes, Sagi; Barkai, Omer; Caspi, Yaki; Katz, Ben; Lev, Shaya

    2014-01-01

    Tetrodotoxin-resistant (TTX-r) sodium channels are key players in determining the input-output properties of peripheral nociceptive neurons. Changes in gating kinetics or in expression levels of these channels by proinflammatory mediators are likely to cause the hyperexcitability of nociceptive neurons and pain hypersensitivity observed during inflammation. Proinflammatory mediator, tumor necrosis factor-α (TNF-α), is secreted during inflammation and is associated with the early onset, as well as long-lasting, inflammation-mediated increase in excitability of peripheral nociceptive neurons. Here we studied the underlying mechanisms of the rapid component of TNF-α-mediated nociceptive hyperexcitability and acute pain hypersensitivity. We showed that TNF-α leads to rapid onset, cyclooxygenase-independent pain hypersensitivity in adult rats. Furthermore, TNF-α rapidly and substantially increases nociceptive excitability in vitro, by decreasing action potential threshold, increasing neuronal gain and decreasing accommodation. We extended on previous studies entailing p38 MAPK-dependent increase in TTX-r sodium currents by showing that TNF-α via p38 MAPK leads to increased availability of TTX-r sodium channels by partial relief of voltage dependence of their slow inactivation, thereby contributing to increase in neuronal gain. Moreover, we showed that TNF-α also in a p38 MAPK-dependent manner increases persistent TTX-r current by shifting the voltage dependence of activation to a hyperpolarized direction, thus producing an increase in inward current at functionally critical subthreshold voltages. Our results suggest that rapid modulation of the gating of TTX-r sodium channels plays a major role in the mediated nociceptive hyperexcitability of TNF-α during acute inflammation and may lead to development of effective treatments for inflammatory pain, without modulating the inflammation-induced healing processes. PMID:25355965

  3. Microenvironment mediated alterations to metabolic pathways confer increased chemo-resistance in CD133+ tumor initiating cells.

    PubMed

    Nomura, Alice; Dauer, Patricia; Gupta, Vineet; McGinn, Olivia; Arora, Nivedita; Majumdar, Kaustav; Uhlrich, Charles; Dalluge, Joseph; Dudeja, Vikas; Saluja, Ashok; Banerjee, Sulagna

    2016-08-30

    Chemoresistance in pancreatic cancer has been attributed to tumor-initiating cells (TICs), a minor sub-population of tumor cells. However, the mechanism of chemo-resistance in these cells is still unclear.In the current study, immunohistochemical analysis of LSL-KrasG12D; LSL-Trp53R172H;PdxCre (KPC) murine tumors indicated that hypoxic regions developed through tumor progression. This hypoxic "niche" correlated with increased CD133+ population that had an increased HIF1A activity. Consistent with this observation, CD133+ cells had increased glucose uptake and activity of glycolytic pathway enzymes compared to CD133- cells. Mass spectrometric analysis (UPLC-TQD) following metabolic labeling of CD133+ cells with [13C]-U6 glucose confirmed this observation. Furthermore, although both populations had functionally active mitochondria, CD133+ cells had low mitochondrial complex I and complex IV activity and lesser accumulation of ROS in response to standard chemotherapeutic compounds like paclitaxel, 5FU and gemcitabine. CD133+ cells also showed increased resistance to all three chemotherapeutic compounds and treatment with Glut1 inhibitor (STF31) reversed this resistance, promoting apoptotic death in these cells similar to CD133- cells.Our study indicates that the altered metabolic profile of CD133+ pancreatic TIC protects them against apoptosis, by reducing accumulation of ROS induced by standard chemotherapeutic agents, thereby confering chemoresistance. Since resistance to existing chemotherapy contributes to the poor prognosis in pancreatic cancer, our study paves the way for identifying novel therapeutic targets for managing chemoresistance and tumor recurrence in pancreatic cancer.

  4. PIK3CA mutations enable targeting of a breast tumor dependency through mTOR-mediated MCL-1 translation

    PubMed Central

    Anderson, Grace R.; Wardell, Suzanne E.; Cakir, Merve; Crawford, Lorin; Leeds, Jim C.; Nussbaum, Daniel P.; Shankar, Pallavi S.; Soderquist, Ryan S.; Stein, Elizabeth M.; Tingley, Jennifer P.; Winter, Peter S.; Zieser-Misenheimer, Elizabeth K.; Alley, Holly M.; Yllanes, Alexander; Haney, Victoria; Blackwell, Kimberly L.; McCall, Shannon J.; McDonnell, Donald P.; Wood, Kris C.

    2017-01-01

    Therapies that efficiently induce apoptosis are likely to be required for durable clinical responses in patients with solid tumors. Using a pharmacological screening approach, we discovered that the combined inhibition of BCL-XL and the mTOR/4E-BP axis results in selective and synergistic induction of apoptosis in cellular and animal models of PIK3CA mutant breast cancers, including triple negative tumors. Mechanistically, inhibition of mTOR/4E-BP suppresses MCL-1 protein translation only in PIK3CA mutant tumors, creating a synthetic dependence on BCL-XL. This dual dependence on BCL-XL and MCL-1, but not on BCL-2, appears to be a fundamental property of diverse breast cancer cell lines, xenografts, and patient-derived tumors that is independent of molecular subtype or PIK3CA mutational status. Further, this dependence distinguishes breast cancers from normal breast epithelial cells, which are neither primed for apoptosis nor dependent on BCL-XL/MCL-1, suggesting a potential therapeutic window. By tilting the balance of pro- to anti-apoptotic signals in the mitochondria, dual inhibition of MCL-1 and BCL-XL also sensitizes breast cancer cells to standard of care cytotoxic and targeted chemotherapies. Together, these results suggest that patients with PIK3CA mutant breast cancers may benefit from combined treatment with inhibitors of BCL-XL and the mTOR/4E-BP axis, whereas alternative methods of inhibiting MCL-1 and BCL-XL may be effective in tumors lacking PIK3CA mutations. PMID:27974663

  5. VEGF is an important mediator of tumor angiogenesis in malignant lesions in a genetically engineered mouse model of lung adenocarcinoma.

    PubMed

    Majeti, Bharat K; Lee, Joseph H; Simmons, Brett H; Shojaei, Farbod

    2013-04-29

    VEGF is one of the key drivers of physiological or pathological angiogenesis hence several VEGF inhibitors are in different stages of clinical development. To further dissect the role of VEGF in different stages of tumor progression in lung tumors, we utilized KrasG12D-LSL GEMMs (genetically engineered mouse models). Intranasal delivery of adenoviruses expressing cre recombinase in KrasG12D-LSL mice results in the expression of mutant Kras that leads to development of tumor lesions ranging from adenomatous hyperplasia to large adenoma and adenocarcinoma over time in lung. In the current study, we treated KrasG12D-LSL mice at 14 weeks post inhalation with three different angiogenic inhibitors including axitinib and PF-00337210 both of which are selective inhibitors of VEGFR and sunitinib which targets VEGFR, C-SF1-R, PDGFR and KIT. Pathology findings showed no significant difference in percentage of adenomatous hyperplastic lesions between the vehicle vs. any of the treatments suggesting that angiogenesis may not play a major role at early stages of tumorigenesis. However, each inhibitor suppressed percentage of benign adenoma lesions and almost fully inhibited growth of adenocarcinoma lesions in the recipients which was consistent with a reduction in tumor vasculature. Treatment with sunitinib which is a multi-targeted RTKI did not provide any advantage compared to selective VEGFR inhibitor further emphasizing role of VEGF in tumor angiogenesis in this model. Overall, our studies indicate significance of VEGF and angiogenesis in a spontaneous model of lung tumorigenesis and provide a proof of mechanism for anti-cancer activity of VEGF inhibitors in this model.

  6. Delta-ALA-mediated fluorescence spectroscopy of gastrointestinal tumors: comparison of in vivo and in vitro results

    NASA Astrophysics Data System (ADS)

    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. Attention-mediated neurocognitive profiles in survivors of pediatric brain tumors: comparison to children with neurodevelopmental ADHD.

    PubMed

    Hardy, Kristina K; Willard, Victoria W; Gioia, Anthony; Sharkey, Christina; Walsh, Karin S

    2018-04-09

    Attention and working memory symptoms are among the most common late effects in survivors of pediatric brain tumors, and are often associated with academic and psychosocial difficulties. Diagnostic and treatment approaches derived from the literature on attention-deficit hyperactivity disorder (ADHD) have frequently been applied to survivors, yet the extent of overlap in cognitive profiles between these groups is unclear. The objective of the present study is to compare neurocognition in survivors of brain tumors and children with neurodevelopmental ADHD. Neuropsychological data were abstracted from clinically referred brain tumor survivors (n = 105, Mage = 12.0 y, 52.4% male) and children with ADHD (n = 178, Mage = 11.1 y, 64.0% male). Data consist of a battery of parent-report questionnaires and performance-based neuropsychological measures. Twenty-five survivors (23.8%) of pediatric brain tumors met symptom criteria for ADHD. Participants with neurodevelopmental ADHD and survivors who met ADHD criteria had significantly greater parent- (P < 0.001) and teacher-reported (P < 0.001) working memory and behavior regulation difficulties than survivors of tumor who did not meet criteria. Children with ADHD symptoms also performed worse on measures of sustained attention than survivors without ADHD symptoms (P < 0.001). Additionally, survivors with ADHD symptoms had greater performance-based working memory difficulties than either survivors without attention problems or children with neurodevelopmental ADHD (P = 0.002). Nearly a quarter of survivors with attention symptoms have functional profiles that are similar to children with neurodevelopmental ADHD. They also experience more neurocognitive impairments than survivors without attentional difficulties, particularly in working memory. Screening for ADHD symptoms may help providers triage a subset of individuals in need of earlier or additional neuropsychological assessment.

  8. p75 Neurotrophin Receptor Cleavage by α- and γ-Secretases Is Required for Neurotrophin-mediated Proliferation of Brain Tumor-initiating Cells*

    PubMed Central

    Forsyth, Peter A.; Krishna, Niveditha; Lawn, Samuel; Valadez, J. Gerardo; Qu, Xiaotao; Fenstermacher, David A.; Fournier, Michelle; Potthast, Lisa; Chinnaiyan, Prakash; Gibney, Geoffrey T.; Zeinieh, Michele; Barker, Philip A.; Carter, Bruce D.; Cooper, Michael K.; Kenchappa, Rajappa S.

    2014-01-01

    Malignant gliomas are highly invasive, proliferative, and resistant to treatment. Previously, we have shown that p75 neurotrophin receptor (p75NTR) is a novel mediator of invasion of human glioma cells. However, the role of p75NTR in glioma proliferation is unknown. Here we used brain tumor-initiating cells (BTICs) and show that BTICs express neurotrophin receptors (p75NTR, TrkA, TrkB, and TrkC) and their ligands (NGF, brain-derived neurotrophic factor, and neurotrophin 3) and secrete NGF. Down-regulation of p75NTR significantly decreased proliferation of BTICs. Conversely, exogenouous NGF stimulated BTIC proliferation through α- and γ-secretase-mediated p75NTR cleavage and release of its intracellular domain (ICD). In contrast, overexpression of the p75NTR ICD induced proliferation. Interestingly, inhibition of Trk signaling blocked NGF-stimulated BTIC proliferation and p75NTR cleavage, indicating a role of Trk in p75NTR signaling. Further, blocking p75NTR cleavage attenuated Akt activation in BTICs, suggesting role of Akt in p75NTR-mediated proliferation. We also found that p75NTR, α-secretases, and the four subunits of the γ-secretase enzyme were elevated in glioblastoma multiformes patients. Importantly, the ICD of p75NTR was commonly found in malignant glioma patient specimens, suggesting that the receptor is activated and cleaved in patient tumors. These results suggest that p75NTR proteolysis is required for BTIC proliferation and is a novel potential clinical target. PMID:24519935

  9. Augmented Serum Amyloid A1/2 Mediated by TNF-induced NF-κB in Human Serous Ovarian Epithelial Tumors

    PubMed Central

    Choi, Hyeongjwa; Ignacio, Rosa Mistica C.; Lee, Eun-Sook; Wilson, Andrew J.; Khabele, Dineo

    2017-01-01

    Tumor necrosis factor-α (TNF) is well known to be involved in the immune system and ovarian inflammation. Ovarian cancer is an inflammation-related malignancy that lacks early screening strategies, resulting in late diagnosis followed by high mortality. Based on our previous data, TNF induced abundant serum amyloid A (SAA), an acute phase protein linked to inflammation, in ovarian granulosal cells. To date, the regulation and expression of SAA in ovarian cancer is not fully elucidated. Here, we investigated the relationship between TNF and SAA by comparing human normal ovarian tissues and serous ovarian tumors. We found that SAA1/2 was significantly expressed in tumor tissues, but no or trace expression levels in normal tissues. TNF was also significantly upregulated in ovarian tumor tissues compared to normal tissues. Moreover, TNF significantly increased SAA1/2 levels in human ovarian cancer cell lines, OVCAR-3 and SKOV-3, in a time-dependent manner. Since the SAA1 promoter contains two nuclear factor (NF)-κB sites, we examined whether TNF regulates SAA1 promoter activity. Deletion analysis revealed that the proximal NF-κB site (−95/−85) played a critical role in regulating TNF-induced SAA1 promoter activity. Within 2 h after intraperitoneal injection of lipopolysaccharide, a product known to stimulate release of TNF, SAA preferably localized to ovarian epithelial cells and the thecal-interstitial layers compared to granulosal cell layers. Based on Gene Expression Omnibus (GEO) database, SAA1/2 and TNF were dominantly expressed in advanced grade ovarian cancer. Taken together, the accumulation of SAA1/2 in ovarian cancer could be mediated by TNF-induced NF-κB activation. PMID:28458624

  10. Rexinoid-triggered differentiation and tumor-selective apoptosis of acute myeloid leukemia by protein kinase A-mediated desubordination of retinoid X receptor.

    PubMed

    Altucci, Lucia; Rossin, Aurélie; Hirsch, Oliver; Nebbioso, Angela; Vitoux, Dominique; Wilhelm, Emmanuelle; Guidez, Fabien; De Simone, Mariacarla; Schiavone, Ettore Mariano; Grimwade, David; Zelent, Arthur; de Thé, Hugues; Gronemeyer, Hinrich

    2005-10-01

    Apart from PML-retinoic acid receptor-alpha (RARalpha) acute promyelocytic leukemia all other acute myeloid leukemias (AML) are unresponsive to retinoid differentiation therapy. However, elevating the levels of cyclic AMP (cAMP) confers onto retinoid X receptor (RXR)-selective agonists ("rexinoids") the ability to induce terminal granulocyte differentiation and apoptosis of all-trans retinoic acid-resistant and insensitive AML cells and patients' blasts. Protein kinase A activation leads to corepressor release from the RAR subunit of the RAR-RXR heterodimer, resulting in "desubordination" of otherwise silent RXR, which acquires transcriptional competence in response to cognate ligands. Rexinoid-cAMP induction of endogenous RARbeta is blunted in mouse embryo fibroblasts lacking RARs, but reintroduction of exogenous RARalpha reestablishes responsiveness, thus confirming that the RARalpha-RXR heterodimer is the rexinoid mediator. The apoptogenic effect of this treatment involves enhanced expression of the death receptor DR5 and its cognate ligand, tumor necrosis factor-related apoptosis inducing ligand, both of which are known to induce apoptosis in a tumor cell-selective manner and lead to the activation of initiator caspases. Immunohistochemistry confirmed induction of tumor necrosis factor-related apoptosis inducing ligand and DR5 in AML patient blasts cultured ex vivo. AML patients' blasts responded to rexinoid-cAMP combination treatment with induction of maturation and apoptosis, independent of karyotype, immunophenotype, and French-American-British classification status. Clonogenic assays revealed complete inhibition of blast clonogenicity in four out of five tested samples. Our results suggest that despite the genetic, morphologic, and clinical variability of this disease, the combination of rexinoids and cAMP-elevating drugs, such as phosphodiesterase inhibitors, might lead to a novel therapeutic option for AML patients by inducing a tumor-selective death

  11. Unimpaired Autoreactive T-Cell Traffic Within the Central Nervous System During Tumor Necrosis Factor Receptor-Mediated inhibition of Experimental Autoimmune Encephalomyelitis

    NASA Astrophysics Data System (ADS)

    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.

  12. Norbixin Protects Retinal Pigmented Epithelium Cells and Photoreceptors against A2E-Mediated Phototoxicity In Vitro and In Vivo

    PubMed Central

    Monteiro, Elodie; Brazhnikova, Elena; Lesage, Laëtitia; Balducci, Christine; Guibout, Louis; Feraille, Laurence; Elena, Pierre-Paul; Sahel, José-Alain; Veillet, Stanislas; Lafont, René

    2016-01-01

    The accumulation of N-retinylidene-N-retinylethanolamine (A2E, a toxic by-product of the visual pigment cycle) in the retinal pigment epithelium (RPE) is a major cause of visual impairment in the elderly. Photooxidation of A2E results in retinal pigment epithelium degeneration followed by that of associated photoreceptors. Present treatments rely on nutrient supplementation with antioxidants. 9’-cis-Norbixin (a natural diapocarotenoid, 97% purity) was prepared from Bixa orellana seeds. It was first evaluated in primary cultures of porcine retinal pigment epithelium cells challenged with A2E and illuminated with blue light, and it provided an improved photo-protection as compared with lutein or zeaxanthin. In Abca4-/- Rdh8-/- mice (a model of dry AMD), intravitreally-injected norbixin maintained the electroretinogram and protected photoreceptors against light damage. In a standard rat blue-light model of photodamage, norbixin was at least equally as active as phenyl-N-tert-butylnitrone, a free radical spin-trap. Chronic experiments performed with Abca4-/- Rdh8-/- mice treated orally for 3 months with norbixin showed a reduced A2E accumulation in the retina. Norbixin appears promising for developing an oral treatment of macular degeneration. A drug candidate (BIO201) with 9’-cis-norbixin as the active principle ingredient is under development, and its potential will be assessed in a forthcoming clinical trial. PMID:27992460

  13. Neutrophil-derived 5′-Adenosine Monophosphate Promotes Endothelial Barrier Function via CD73-mediated Conversion to Adenosine and Endothelial A2B Receptor Activation

    PubMed Central

    Lennon, Paul F.; Taylor, Cormac T.; Stahl, Gregory L.; Colgan, Sean P.

    1998-01-01

    During episodes of inflammation, polymorphonuclear leukocyte (PMN) transendothelial migration has the potential to disturb vascular barrier function and give rise to intravascular fluid extravasation and edema. However, little is known regarding innate mechanisms that dampen fluid loss during PMN-endothelial interactions. Using an in vitro endothelial paracellular permeability model, we observed a PMN-mediated decrease in endothelial paracellular permeability. A similar decrease was elicited by cell-free supernatants from activated PMN (FMLP 10−6 M), suggesting the presence of a PMN-derived soluble mediator(s). Biophysical and biochemical analysis of PMN supernatants revealed a role for PMN-derived 5′-adenosine monophosphate (AMP) and its metabolite, adenosine, in modulation of endothelial paracellular permeability. Supernatants from activated PMN contained micromolar concentrations of bioactive 5′-AMP and adenosine. Furthermore, exposure of endothelial monolayers to authentic 5′-AMP and adenosine increased endothelial barrier function more than twofold in both human umbilical vein endothelial cells and human microvascular endothelial cells. 5′-AMP bioactivity required endothelial CD73-mediated conversion of 5′-AMP to adenosine via its 5′-ectonucleotidase activity. Decreased endothelial paracellular permeability occurred through adenosine A2B receptor activation and was accompanied by a parallel increase in intracellular cAMP. We conclude that activated PMN release soluble mediators, such as 5′-AMP and adenosine, that promote endothelial barrier function. During inflammation, this pathway may limit potentially deleterious increases in endothelial paracellular permeability and could serve as a basic mechanism of endothelial resealing during PMN transendothelial migration. PMID:9782120

  14. Tumor suppressor in lung cancer-1 (TSLC1) mediated by dual-regulated oncolytic adenovirus exerts specific antitumor actions in a mouse model.

    PubMed

    Lei, Wen; Liu, Hong-bin; Wang, Shi-bing; Zhou, Xiu-mei; Zheng, Shui-di; Guo, Ke-ni; Ma, Bu-yun; Xia, Yu-long; Tan, Wen-song; Liu, Xin-yuan; Wang, Yi-gang

    2013-04-01

    The tumor suppressor in lung cancer-1 (TSLC1) is a candidate tumor suppressor of lung cancer, and frequently inactivated in primary non-small cell lung cancer (NSCLC). In this study, we investigated the effects of TSLC1 mediated by a dual-regulated oncolytic adenovirus on lung cancer, and the mechanisms underlying the antitumor actions. The recombinant virus Ad·sp-E1A(Δ24)-TSLC1 was constructed by inserting the TSLC1 gene into the dual-regulated Ad·sp-E1A(Δ24) vector, which contained the survivin promoter and a 24 bp deletion within E1A. The antitumor effects of Ad·sp-E1A(Δ24)-TSLC1 were evaluated in NCI-H460, A549, and H1299 lung cancer cell lines and the normal fibroblast cell line MRC-5, as well as in A549 xenograft model in nude mice. Cell viability was assessed using MTT assay. The expression of TSLC1 and activation of the caspase signaling pathway were detected by Western blot analyses. The tumor tissues from the xenograft models were examined using H&E staining, IHC, TUNEL, and TEM analyses. Infection of A549 lung cancer cells with Ad·sp-E1A(Δ24)-TSLC1 induced high level expression of TSLC1. Furthermore, the Ad·sp-E1A(Δ24)-TSLC1 virus dose-dependently suppressed the viability of NCI-H460, A549, and H1299 lung cancer cells, and did not affect MRC-5 normal fibroblast cells. Infection of NCI-H460, A549, and H1299 lung cancer cells with Ad·sp-E1A(Δ24)-TSLC1 induced apoptosis, and increased activation of caspase-8, caspase-3 and PARP. In A549 xenograft model in nude mice, intratumoral injection of Ad·sp-E1A(Δ24)-TSLC1 significantly suppressed the tumor volume, and increased the survival rate (from less than 15% to 87.5% at d 60). Histological studies showed that injection of Ad·sp-E1A(Δ24)-TSLC1 caused tumor cell apoptosis and virus particle propagation in tumor tissues. The oncolytic adenovirus Ad·sp-E1A(Δ24)-TSLC1 exhibits specific antitumor effects, and is a promising agent for the treatment of lung cancer.

  15. Peptide-Mediated Tumor Targeting by a Degradable Nano Gene Delivery Vector Based on Pluronic-Modified Polyethylenimine

    NASA Astrophysics Data System (ADS)

    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.

  16. Suppression of colorectal cancer subcutaneous xenograft and experimental lung metastasis using nanoparticle-mediated drug delivery to tumor neovasculature.

    PubMed

    Wang, Chao; Zhao, Mei; Liu, Ya-Rong; Luan, Xin; Guan, Ying-Yun; Lu, Qin; Yu, De-Hong; Bai, Fan; Chen, Hong-Zhuan; Fang, Chao

    2014-01-01

    Antiangiogenic therapy is a validated approach for colorectal cancer (CRC) treatment. However, diverse adverse effects inevitably appear due to the off-target effect of the approved antiangiogenic inhibitors on the physiological functions and homeostasis. This study was to investigate a new tumor vessel targeting nanoparticulate drug delivery system, F56 peptide conjugated nanoparticles loading vincristine (F56-VCR-NP), for the effective treatment of CRC subcutaneous xenograft and experimental lung metastasis model. The controlled release behavior and in vivo pharmacokinetic profile of F56-VCR-NP were characterized. The tumor vessel targeting and antiangiogenic activity of F56-VCR-NP was evaluated in human umbilical vein endothelial cells (HUVEC, a classical cell model mimicking tumor vascular EC), subcutaneous human HCT-15 xenograft in immunodeficient nude mice, and experimental CT-26 lung metastasis model in immunocompetent mice. The therapeutic efficacy (animal survival and toxicity) was further investigated in the model of CT-26 lung metastasis in mice. F56-VCR-NP could achieve 30-day controlled drug release in PBS (pH 7.4) and exhibited favorable long-circulating feature in vivo. F56-VCR-NP could accurately target the CRC neovasculature and elicit nanoparticle internalization in the tumor vascular EC, where the antiangiogenic VCR-induced dramatic EC apoptosis and necrosis of CRC tissue. F56-VCR-NP significantly prolonged the mouse survival with no obvious toxicity (weight loss and anepithymia) in the CT-26 lung metastasis mice model, and this pronounced antitumor effect was closely related with the decreased microvessel density in the metastases. The present nanoparticle-based targeted antiangiogenic therapy may provide a new promising approach for the therapy of CRC and lung metastasis, which deserves further translational research. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Heat-shock induction of tumor-derived danger signals mediates rapid monocyte differentiation into clinically effective dendritic cells.

    PubMed

    Aguilera, Raquel; Saffie, Carlos; Tittarelli, Andrés; González, Fermín E; Ramírez, Marcos; Reyes, Diego; Pereda, Cristián; Hevia, Daniel; García, Tamara; Salazar, Lorena; Ferreira, Arturo; Hermoso, Marcela; Mendoza-Naranjo, Ariadna; Ferrada, Carlos; Garrido, Paola; López, Mercedes N; Salazar-Onfray, Flavio

    2011-04-15

    This study characterizes, biologically and clinically, a novel type of dendritic cells (DC) produced in the short term and called tumor antigen-presenting cells (TAPCells). In particular, we identified factors present in a lysate derived from heat-shocked allogeneic melanoma cells (TRIMEL) that are associated with TAPCells' enhanced capability to induce CD8(+) T-cell responses in vitro and in vaccinated melanoma patients. First, extensive phenotypic and functional characterization of TAPCells was performed, followed by vaccination of 45 melanoma patients with four doses of TAPCells over a period of 2 months. Specific delayed-type hypersensitivity (DTH) reaction was analyzed posttreatment and correlated with overall survival rates. Furthermore, heat-shock (HS)-induced factors present in TRIMEL and their effects on DC activation were identified and studied. TRIMEL induced a committed, mature, DC-like phenotype in TAPCells and effectively activated melanoma-specific CD4(+) and CD8(+) T cells. Clinically, 64% of vaccinated patients showed positive DTH reaction against TRIMEL, and this was associated with improved overall survival. HS treatment of tumor cells increased calreticulin (CRT) plasma membrane translocation and induced the release of high-mobility group box 1 proteins (HMGB1). Both CRT and HMGB1 mobilization were associated with enhanced TAPCells' maturation and antigen (Ag) cross-presentation, respectively. DTH infiltration analysis revealed the presence of CD8(+)/CD45RO(+) T cells, thus confirming TAPCells' ability to cross-present Ags in vivo. Our results indicate that lysates derived from heat-shocked tumor cells are an optimal source of tumor-associated Ags, which are crucial for the generation of DCs with improved Ag cross-presentation capacity and clinically effective immunogenicity. ©2011 AACR.

  18. Peptide-Mediated Tumor Targeting by a Degradable Nano Gene Delivery Vector Based on Pluronic-Modified Polyethylenimine.

    PubMed

    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.

  19. Flt3L in combination with HSV1-TK-mediated gene therapy reverses brain tumor-induced behavioral deficits.

    PubMed

    King, Gwendalyn D; Kroeger, Kurt M; Bresee, Catherine J; Candolfi, Marianela; Liu, Chunyan; Manalo, Charlene M; Muhammad, A K M Ghulam; Pechnick, Robert N; Lowenstein, Pedro R; Castro, Maria G

    2008-04-01

    Glioblastoma multiforme (GBM) is an invasive and aggressive primary brain tumor which is associated with a dismal prognosis. We have earlier developed a macroscopic, intracranial, syngeneic GBM model, in which treatment with adenoviral vectors (Ads) expressing herpes simplex virus type 1 thymidine kinase (HSV1-TK) plus ganciclovir (GCV) resulted in survival of approximately 20% of the animals. In this model, treatment with Ads expressing Fms-like tyrosine kinase 3 ligand (Flt3L), in combination with Ad-HSV1-TK improves the survival rate to approximately 70% and induces systemic antitumor immunity. We hypothesized that the growth of a large intracranial tumor mass would cause behavioral abnormalities that can be reversed by the combined gene therapy. We assessed the behavior and neuropathology of tumor-bearing animals treated with the combined gene therapy, 3 days after treatment, in long-term survivors, and in a recurrent model of glioma. We demonstrate that the intracranial GBM induces behavioral deficits that are resolved after treatment with Ad-Flt3L/Ad-TK (+GCV). Neuropathological analysis of long-term survivors revealed an overall recovery of normal brain architecture. The lack of long-term behavioral deficits and limited neuropathological abnormalities demonstrate the efficacy and safety of the combined Ad-Flt3L/Ad-TK gene therapy for GBM. These findings can serve to underpin further developments of this therapeutic modality, leading toward implementation of a Phase I clinical trial.

  20. Ergosterol peroxide isolated from Ganoderma lucidum abolishes microRNA miR-378-mediated tumor cells on chemoresistance.

    PubMed

    Wu, Qing-Ping; Xie, Yi-Zhen; Deng, Zhaoqun; Li, Xiang-Min; Yang, Weining; Jiao, Chun-Wei; Fang, Ling; Li, Sen-Zhu; Pan, Hong-Hui; Yee, Albert J; Lee, Daniel Y; Li, Chong; Zhang, Zhi; Guo, Jun; Yang, Burton B

    2012-01-01

    Due to an altered expression of oncogenic factors and tumor suppressors, aggressive cancer cells have an intrinsic or acquired resistance to chemotherapeutic agents. This typically contributes to cancer recurrence after chemotherapy. microRNAs are short non-coding RNAs that are involved in both cell self-renewal and cancer development. Here we report that tumor cells transfected with miR-378 acquired properties of aggressive cancer cells. Overexpression of miR-378 enhanced both cell survival and colony formation, and contributed to multiple drug resistance. Higher concentrations of chemotherapeutic drugs were needed to induce death of miR-378-transfected cells than to induce death of control cells. We found that the biologically active component isolated from Ganoderma lucidum could overcome the drug-resistance conferred by miR-378. We purified and identified the biologically active component of Ganoderma lucidum as ergosterol peroxide. We demonstrated that ergosterol peroxide produced greater activity in inducing death of miR-378 cells than the GFP cells. Lower concentrations of ergosterol peroxide were needed to induce death of the miR-378-transfected cells than in the control cells. With further clinical development, ergosterol peroxide represents a promising new reagent that can overcome the drug-resistance of tumor cells.

  1. Ergosterol Peroxide Isolated from Ganoderma lucidum Abolishes MicroRNA miR-378-Mediated Tumor Cells on Chemoresistance

    PubMed Central

    Li, Xiang-Min; Yang, Weining; Jiao, Chun-Wei; Fang, Ling; Li, Sen-Zhu; Pan, Hong-Hui; Yee, Albert J.; Lee, Daniel Y.; Li, Chong; Zhang, Zhi; Guo, Jun; Yang, Burton B.

    2012-01-01

    Due to an altered expression of oncogenic factors and tumor suppressors, aggressive cancer cells have an intrinsic or acquired resistance to chemotherapeutic agents. This typically contributes to cancer recurrence after chemotherapy. microRNAs are short non-coding RNAs that are involved in both cell self-renewal and cancer development. Here we report that tumor cells transfected with miR-378 acquired properties of aggressive cancer cells. Overexpression of miR-378 enhanced both cell survival and colony formation, and contributed to multiple drug resistance. Higher concentrations of chemotherapeutic drugs were needed to induce death of miR-378-transfected cells than to induce death of control cells. We found that the biologically active component isolated from Ganoderma lucidum could overcome the drug-resistance conferred by miR-378. We purified and identified the biologically active component of Ganoderma lucidum as ergosterol peroxide. We demonstrated that ergosterol peroxide produced greater activity in inducing death of miR-378 cells than the GFP cells. Lower concentrations of ergosterol peroxide were needed to induce death of the miR-378-transfected cells than in the control cells. With further clinical development, ergosterol peroxide represents a promising new reagent that can overcome the drug-resistance of tumor cells. PMID:22952996

  2. Apoptosis mediated chemosensitization of tumor cells to 5-fluorouracil on supplementation of fish oil in experimental colon carcinoma.

    PubMed

    Rani, Isha; Sharma, Bhoomika; Kumar, Sandeep; Kaur, Satinder; Agnihotri, Navneet

    2017-03-01

    5-Fluorouracil has been considered as a cornerstone therapy for colorectal cancer; however, it suffers from low therapeutic response rate and severe side effects. Therefore, there is an urgent need to increase the clinical efficacy of 5-fluorouracil. Recently, fish oil rich in n-3 polyunsaturated fatty acids has been reported to chemosensitize tumor cells to anti-cancer drugs. This study is designed to understand the underlying mechanisms of synergistic effect of fish oil and 5-fluorouracil by evaluation of tumor cell-associated markers such as apoptosis and DNA damage. The colon cancer was developed by administration of N,N-dimethylhydrazine dihydrochloride and dextran sulfate sodium salt. Further these animals were treated with 5-fluorouracil, fish oil, or a combination of both. In carcinogen-treated animals, a decrease in DNA damage and apoptotic index was observed. There was also a decrease in the expression of Fas, FasL, caspase 8, and Bax, and an increase in Bcl-2. In contrast, administration of 5-fluorouracil and fish oil as an adjuvant increased both DNA damage and apoptotic index by activation of both extrinsic and intrinsic apoptotic pathways as compared to the other groups. The increased pro-apoptotic effect by synergism of 5-fluorouracil and fish oil may be attributed to the incorporation of n-3 polyunsaturated fatty acids in membrane, which alters membrane fluidity in cancer cells. In conclusion, this study highlights that the induction of apoptotic pathway by fish oil may increase the susceptibility of tumors to chemotherapeutic regimens.

  3. Caffeine mediates sustained inactivation of breast cancer-associated myofibroblasts via up-regulation of tumor suppressor genes.

    PubMed

    Al-Ansari, Mysoon M; Aboussekhra, Abdelilah

    2014-01-01

    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. 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. 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.

  4. Immunostimulatory properties and enhanced TNF- α mediated cellular immunity for tumor therapy by C60(OH)20 nanoparticles

    NASA Astrophysics Data System (ADS)

    Liu, Ying; Jiao, Fang; Qiu, Yang; Li, Wei; Qu, Ying; Tian, Chixia; Li, Yufeng; Bai, Ru; Lao, Fang; Zhao, Yuliang; Chai, Zhifang; Chen, Chunying

    2009-10-01

    Publications concerning the mechanism of biological activity, especially the immunological mechanism of C60(OH)20 nanoparticles, are relatively limited. However, the structure and characteristics of this carbon allotrope have been widely investigated. In this paper, we have demonstrated that water-soluble C60(OH)20 nanoparticles have an efficient anti-tumor activity in vivo, and show specific immunomodulatory effects to the immune cells, such as T cells and macrophages, both in vivo and in vitro. For example, C60(OH)20 nanoparticles can increase the production of T-helper cell type 1 (Th1) cytokines (IL-2, IFN- γ and TNF-α), and decrease the production of Th2 cytokines (IL-4, IL-5 and IL-6) in serum samples. On the other hand, C60(OH)20 nanoparticles show almost no adverse effect to the viability of immune cells in vitro but stimulate the immune cells to release more cytokines, in particular TNF- α, which plays a key role in the cellular immune process to help eliminate abnormal cells. TNF- α production increased almost three-fold in treated T lymphocytes and macrophages. Accordingly, we conclude that C60(OH)20 nanoparticles have an efficient anti-tumor activity and this effect is associated with an increased CD4+/CD8+ lymphocyte ratio and the enhancement of TNF- α production. The data suggest that C60(OH)20 nanoparticles can improve the immune response to help to scavenge and kill tumor cells.

  5. Annexin A2 Promotes the Migration and Invasion of Human Hepatocellular Carcinoma Cells In Vitro by Regulating the Shedding of CD147-Harboring Microvesicles from Tumor Cells

    PubMed Central

    Cai, Lei; Song, Zhen-Shun; Cao, Da-Yong; Tao, Kai-Shan; Zhou, Wen-Ping; Chen, Zhi-Nan; Dou, Ke-Feng

    2013-01-01

    It has been reported that Annexin A2 (ANXA2) is up-regulated in hepatocellular carcinoma (HCC), but the roles of ANXA2 in the migration and invasion of HCC cells have not been determined. In this study, we found that ANXA2-specific siRNA (si-ANXA2) significantly inhibited the migration and invasion of HCC cells co-cultured with fibroblasts in vitro. In addition, the production of MMP-2 by fibroblasts cultured in supernatant collected from si-ANXA2-transfected HCC cells was notably down-regulated. ANXA2 was also found to be co-localized and co-immunoprecipitated with CD147. Further investigation revealed that the expression of ANXA2 in HCC cells affected the shedding of CD147-harboring membrane microvesicles, acting as a vehicle for CD147 in tumor-stromal interactions and thereby regulating the production of MMP-2 by fibroblasts. Together, these results suggest that ANXA2 enhances the migration and invasion potential of HCC cells in vitro by regulating the trafficking of CD147-harboring membrane microvesicles. PMID:23950866

  6. Ibrutinib interferes with the cell-mediated anti-tumor activities of therapeutic CD20 antibodies: implications for combination therapy

    PubMed Central

    Roit, Fabio Da; Engelberts, Patrick J.; Taylor, Ronald P.; Breij, Esther C.W.; Gritti, Giuseppe; Rambaldi, Alessandro; Introna, Martino; Parren, Paul W.H.I.; Beurskens, Frank J.; Golay, Josée

    2015-01-01

    The novel Bruton tyrosine kinase inhibitor ibrutinib and phosphatidyl-4-5-biphosphate 3-kinase-δ inhibitor idelalisib are promising drugs for the treatment of chronic lymphocytic leukemia and B-cell non-Hodgkin lymphoma, either alone or in combination with anti-CD20 antibodies. We investigated 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, and antibody-dependent cellular cytotoxicity by these cells, as well as phagocytosis by macrophages or neutrophils were inhibited by ibrutinib with a half maximal effective concentration of 0.3–3 μM. Analysis of anti-CD20 mediated activation of natural killer cells isolated from patients on continued oral ibrutinib treatment suggested that repeated drug dosing inhibits these cells in vivo. Finally we show that the phosphatidyl-4-5-biphosphate 3-kinase-δ inhibitor idelalisib similarly inhibited the immune cell-mediated mechanisms induced by anti-CD20 antibodies, although the effects of this drug at 10 μM were weaker than those observed with ibrutinib at the same concentration. We conclude that the design of combined treatment schedules of anti-CD20 antibodies with these kinase inhibitors should consider the multiple negative interactions between these two classes of drugs. PMID:25344523

  7. Pituitary Tumors

    MedlinePlus

    ... Tumor Symptoms Diagnosis Types of Tumors Tumor Grade Risk Factors Brain Tumor Statistics ABTA Publications Brain Tumor Dictionary Upcoming Webinars Anytime Learning Brain Tumor Educational Presentations Adolescent & Pediatric Brain Tumors In Children Pediatric Brain Tumor ...

  8. Ultrasound-targeted microbubble destruction-mediated Foxp3 knockdown may suppress the tumor growth of HCC mice by relieving immunosuppressive Tregs function.

    PubMed

    Shi, Chunying; Zhang, Yu; Yang, Haichao; Dong, Tianxiu; Chen, Yaodong; Xu, Yutong; Yang, Xiuhua; Liu, Pengfei

    2018-01-01

    The aim of the present study was to investigate the effect of Forkhead family transcription factor P3 (Foxp3) knockdown on the function of cluster of differentiation (CD)4 + CD25 + regulatory T cell (Tregs) and the tumor growth of a hepatocellular carcinoma (HCC) mouse model. CD4 + CD25 + Tregs and CD4 + CD25 - T cells were sorted from peripheral blood mononuclear cells (PBMCs) of patients with HCC. Then, ultrasound-targeted microbubble destruction (UTMD)-mediated Foxp3-microRNA (miRNA) was transfected into Tregs. Subsequently, CD4 + CD25 - T cells were co-cultured with PBMC and Tregs without Foxp3-miRNA (Foxp3 + Tregs) or Tregs with Foxp3-miRNA (Foxp3 - Tregs) and the proliferation-inhibition ratio of CD4 + CD25 - T cells was detected using a Cell Counting Kit-8. Additionally, HCC mice were treated with UTMD-mediated Foxp3-shRNA, the tumor volume was calculated and the content of CD4 + and CD25 + T cells in the blood were detected using flow cytometry. The content of interferon-γ (IFN-γ), interleukin (IL)-2, IL-10, transforming growth factor-β (TGF-β) and vascular endothelial growth factor (VEGF) in cultural supernatant and serum were detected by ELISA analysis. Foxp3 - Tregs significantly reduced the inhibition effect of Foxp3 + Tregs on the proliferation of CD4 + CD25 - T cells (P<0.01). The content of IFN-γ and IL-2 significantly increased, while IL-10 and TGF-β significantly decreased in the co-cultured system of Foxp3 - Tregs compared with the co-cultured system of Foxp3 + Tregs (P<0.01). Following treatment with Foxp3-shRNA, the average tumor volume, ratio of Tregs/CD4 + T cells and level of IL-10, TGF-β and VEGF significantly decreased, however, the level of IFN-γ and IL-2 significantly increased compared with un-treated HCC mice (P<0.05). Foxp3 knockdown may suppress the tumor growth of HCC mice through relieving the immunosuppressive function of Tregs.

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

    PubMed Central

    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

  10. Cleavage of p53-Vimentin Complex Enhances Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand-Mediated Apoptosis of Rheumatoid Arthritis Synovial Fibroblasts

    PubMed Central

    Yang, Xinwen; Wang, Jianhua; Liu, Cunren; Grizzle, William E.; Yu, Shaohua; Zhang, Shuangqin; Barnes, Stephen; Koopman, William J.; Mountz, John D.; Kimberly, Robert P.; Zhang, Huang-Ge

    2005-01-01

    Rheumatoid arthritis synovial fibroblasts (RASFs) contribute to arthritic cartilage degradation. Although RASFs are normally resistant to apoptosis, Apo2L/tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-based gene therapy has been successfully used in a mouse model of arthritis. We investigated this further by treating human RASFs with nontoxic doses of the proteasome inhibitor lactacystin. Treatment induced cytosolic accumulation of p53 and enhanced the susceptibility of RASFs to apoptosis mediated by TRAIL-R2 (DR5) but not Fas. A specific role for p53 in TRAIL-R2-mediated apoptosis was indicated by the ability of p53 siRNA to significantly reduce RASF apoptosis and by the reduced apoptosis of RASFs bearing p53 mutations on treatment with anti-DR5 antibody or anti-DR5 antibody plus lactacystin. p53 immunoprecipitation followed by mass spectrometry identified a vimentin-p53 complex, an interaction that was confirmed by reciprocal vimentin-p53 immunoprecipitation and by co-immunofluorescence. Interestingly, human caspase-4 cleaved human vimentin, and blockade of caspase-4 with a chemical inhibitor or with specific siRNA significantly inhibited TRAIL-R2-mediated apoptosis of RASFs. Furthermore, blockade of caspase-4 was paralleled by persistence of a cytosolic pattern of p53 and absence of p53 translocation to the nucleus. Taken together, our findings suggest a unique role for caspase-4 in cleaving vimentin and releasing cytosolic p53 for nuclear translocation, events that may regulate the sensitivity of RASFs to receptor-mediated apoptosis. PMID:16127151

  11. Pathophysiology of isoprostanes in the cardiovascular system: implications of isoprostane-mediated thromboxane A2 receptor activation.

    PubMed

    Bauer, Jochen; Ripperger, Anne; Frantz, Stefan; Ergün, Süleyman; Schwedhelm, Edzard; Benndorf, Ralf A

    2014-07-01

    Isoprostanes are free radical-catalysed PG-like products of unsaturated fatty acids, such as arachidonic acid, which are widely recognized as reliable markers of systemic lipid peroxidation and oxidative stress in vivo. Moreover, activation of enzymes, such as COX-2, may contribute to isoprostane formation. Indeed, formation of isoprostanes is considerably increased in various diseases which have been linked to oxidative stress, such as cardiovascular disease (CVD), and may predict the atherosclerotic burden and the risk of cardiovascular complications in the latter patients. In addition, several isoprostanes may directly contribute to the functional consequences of oxidant stress via activation of the TxA2 prostanoid receptor (TP), for example, by affecting endothelial cell function and regeneration, vascular tone, haemostasis and ischaemia/reperfusion injury. In this context, experimental and clinical data suggest that selected isoprostanes may represent important alternative activators of the TP receptor when endogenous TxA2 levels are low, for example, in aspirin-treated individuals with CVD. In this review, we will summarize the current understanding of isoprostane formation, biochemistry and (patho) physiology in the cardiovascular context. © 2014 The British Pharmacological Society.

  12. Pathophysiology of isoprostanes in the cardiovascular system: implications of isoprostane-mediated thromboxane A2 receptor activation

    PubMed Central

    Bauer, Jochen; Ripperger, Anne; Frantz, Stefan; Ergün, Süleyman; Schwedhelm, Edzard; Benndorf, Ralf A

    2014-01-01

    Isoprostanes are free radical-catalysed PG-like products of unsaturated fatty acids, such as arachidonic acid, which are widely recognized as reliable markers of systemic lipid peroxidation and oxidative stress in vivo. Moreover, activation of enzymes, such as COX-2, may contribute to isoprostane formation. Indeed, formation of isoprostanes is considerably increased in various diseases which have been linked to oxidative stress, such as cardiovascular disease (CVD), and may predict the atherosclerotic burden and the risk of cardiovascular complications in the latter patients. In addition, several isoprostanes may directly contribute to the functional consequences of oxidant stress via activation of the TxA2 prostanoid receptor (TP), for example, by affecting endothelial cell function and regeneration, vascular tone, haemostasis and ischaemia/reperfusion injury. In this context, experimental and clinical data suggest that selected isoprostanes may represent important alternative activators of the TP receptor when endogenous TxA2 levels are low, for example, in aspirin-treated individuals with CVD. In this review, we will summarize the current understanding of isoprostane formation, biochemistry and (patho) physiology in the cardiovascular context. PMID:24646155

  13. Auxins action on Glycine max secretory phospholipase A2 is mediated by the interfacial properties imposed by the phytohormones.

    PubMed

    Mariani, María Elisa; Madoery, Ricardo Román; Fidelio, Gerardo Daniel

    2015-07-01

    Secretory phospholipase A2 (sPLA2) are soluble enzymes that catalyze the conversion of phospholipids to lysophospholipids and free fatty acids at membrane interfaces. The effect of IAA and IPA auxins over the activity of recombinant sPLA2 isoforms from Glycine max was studied using membrane model systems including mixed micelles and Langmuir lipid monolayers. Both phytohormones stimulate the activity of both plant sPLA2 using DLPC/Triton mixed micelles as substrate. To elucidate the mechanism of action of the phytohormones, we showed that both auxins are able to self-penetrate lipid monolayers and cause an increment in surface pressure and an expansion of lipid/phytohormone mixed interfaces. The stimulating effect of auxins over phospholipase A2 activity was still present when using Langmuir mixed monolayers as organized substrate regardless of sPLA2 source (plant or animal). All the data suggest that the stimulating effect of auxins over sPLA2 is due to a more favorable interfacial environment rather to a direct effect over the enzyme. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  14. Caffeine Mediates Sustained Inactivation of Breast Cancer-Associated Myofibroblasts via Up-Regulation of Tumor Suppressor Genes

    PubMed Central

    Al-Ansari, Mysoon M.; Aboussekhra, Abdelilah

    2014-01-01

    Background Active cancer-associated fibroblasts (CAFs) or myofibroblasts play important roles not only in the development and progression of breast carcinomas, but also in their prognosis and treatment. Therefore, targeting these cells through suppressing their supportive procarcinogenic paracrine effects is mandatory for improving the current therapies that are mainly targeting tumor cells. To this end, we investigated the effect of the natural and pharmacologically safe molecule, caffeine, on CAF cells and their various procarcinogenic effects. Methodology/Principal Findings We have shown here that caffeine up-regulates the tumor suppressor proteins p16, p21, p53 and Cav-1, and reduces the expression/secretion of various cytokines (IL-6, TGF-β, SDF-1 and MMP-2), and down-regulates α-SMA. Furthermore, caffeine suppressed the migratory/invasiveness abilities of CAF cells through PTEN-dependent Akt/Erk1/2 inactivation. Moreover, caffeine reduced the paracrine pro-invasion/−migration effects of CAF cells on breast cancer cells. These results indicate that caffeine can inactivate breast stromal myofibroblasts. This has been confirmed by showing that caffeine also suppresses the paracrine pro-angiogenic effect of CAF cells through down-regulating HIF-1αand its downstream effector VEGF-A. Interestingly, these effects were sustained in absence of caffeine. Conclusion/Significance The present findings provide a proof of principle that breast cancer myofibroblasts can be inactivated, and thereby caffeine may provide a safe and effective prevention against breast tumor growth/recurrence through inhibition of the procarcinogenic effects of active stromal fibroblasts. PMID:24595168

  15. HDAC inhibitor valproic acid enhances tumor cell kill in adenovirus-HSVtk mediated suicide gene therapy in HNSCC xenograft mouse model.

    PubMed

    Kothari, Vishal; Joshi, Ganesh; Nama, Srikanth; Somasundaram, Kumaravel; Mulherkar, Rita

    2010-02-01

    Safety, efficacy and enhanced transgene expression are the primary concerns while using any vector for gene therapy. One of the widely used vectors in clinical trials is adenovirus which provides a safe way to deliver the therapeutic gene. However, adenovirus has poor transduction efficiency in vivo since most tumor cells express low coxsackie and adenovirus receptors. Similarly transgene expression remains low, possibly because of the chromatization of adenoviral genome upon infection in eukaryotic cells, an effect mediated by histone deacetylases (HDACs). Using a recombinant adenovirus (Ad-HSVtk) carrying the herpes simplex thymidine kinase (HSVtk) and GFP genes we demonstrate that HDAC inhibitor valproic acid can bring about an increase in CAR expression on host cells and thereby enhanced Ad-HSVtk infectivity. It also resulted in an increase in transgene (HSVtk and GFP) expression. This, in turn, resulted in increased cell kill of HNSCC cells, following ganciclovir treatment in vitro as well as in vivo in a xenograft nude mouse model.

  16. Focal Adhesion- and IGF1R-Dependent Survival and Migratory Pathways Mediate Tumor Resistance to mTORC1/2 Inhibition.

    PubMed

    Yoon, Sang-Oh; Shin, Sejeong; Karreth, Florian A; Buel, Gwen R; Jedrychowski, Mark P; Plas, David R; Dedhar, Shoukat; Gygi, Steven P; Roux, Philippe P; Dephoure, Noah; Blenis, John

    2017-08-03

    Aberrant signaling by the mammalian target of rapamycin (mTOR) contributes to the devastating features of cancer cells. Thus, mTOR is a critical therapeutic target and catalytic inhibitors are being investigated as anti-cancer drugs. Although mTOR inhibitors initially block cell proliferation, cell viability and migration in some cancer cells are quickly restored. Despite sustained inhibition of mTORC1/2 signaling, Akt, a kinase regulating cell survival and migration, regains phosphorylation at its regulatory sites. Mechanistically, mTORC1/2 inhibition promotes reorganization of integrin/focal adhesion kinase-mediated adhesomes, induction of IGFR/IR-dependent PI3K activation, and Akt phosphorylation via an integrin/FAK/IGFR-dependent process. This resistance mechanism contributes to xenograft tumor cell growth, which is prevented with mTOR plus IGFR inhibitors, supporting this combination as a therapeutic approach for cancers. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. The chemokine CCL5 induces CCR1-mediated hyperalgesia in mice inoculated with NCTC 2472 tumoral cells.

    PubMed

    Pevida, M; Lastra, A; Meana, Á; Hidalgo, A; Baamonde, A; Menéndez, Luis

    2014-02-14

    Although the expression of the chemokine receptor CCR1 has been demonstrated in several structures related to nociception, supporting the nociceptive role of chemokines able to activate it, the involvement of CCR1 in neoplastic pain has not been previously assessed. We have assayed the effects of a CCR1 antagonist, J113863, in two murine models of neoplastic hyperalgesia based on the intratibial injection of either NCTC 2472 fibrosarcoma cells, able to induce osteolytic bone injury, or B16-F10 melanoma cells, associated to mixed osteolytic/osteoblastic bone pathological features. The systemic administration of J113863 inhibited thermal and mechanical hyperalgesia but not mechanical allodynia in mice inoculated with NCTC 2472 cells. Moreover, in these mice, thermal hyperalgesia was counteracted following the peritumoral (10-30μg) but not spinal (3-5μg) administration of J113863. In contrast, hyperalgesia and allodynia measured in mice inoculated with B16-F10 cells remained unaffected after the administration of J113863. The inoculation of tumoral cells did not modify the levels of CCL3 at tumor or spinal cord. In contrast, although the concentration of CCL5 remained unmodified in mice inoculated with B16-F10 cells, increased levels of this chemokine were measured in tumor-bearing limbs, but not the spinal cord, of mice inoculated with NCTC 2472 cells. Increased levels of CCL5 were also found following the incubation of NCTC 2472, but not B16-F10, cells in the corresponding culture medium. The intraplantar injection of CCL5 (0.5ng) to naïve mice evoked thermal hyperalgesia prevented by the coadministration of J113863 or the CCR5 antagonist, d-Ala-peptide T-amide (DAPTA), demonstrating that CCL5 can induce thermal hyperalgesia in mice through the activation of CCR1 or CCR5. However, contrasting with the inhibitory effect evoked by J113863, the systemic administration of DAPTA did not prevent tumoral hyperalgesia. Finally, the peritumoral administration of an anti

  18. Antibody-mediated blockade of integrin alpha v beta 6 inhibits tumor progression in vivo by a transforming growth factor-beta-regulated mechanism.

    PubMed

    Van Aarsen, Louise A Koopman; Leone, Diane R; Ho, Steffan; Dolinski, Brian M; McCoon, Patricia E; LePage, Doreen J; Kelly, Rebecca; Heaney, Glenna; Rayhorn, Paul; Reid, Carl; Simon, Kenneth J; Horan, Gerald S; Tao, Nianjun; Gardner, Humphrey A; Skelly, Marilyn M; Gown, Allen M; Thomas, Gareth J; Weinreb, Paul H; Fawell, Stephen E; Violette, Shelia M

    2008-01-15

    The alpha(v)beta(6) integrin is up-regulated on epithelial malignancies and has been implicated in various aspects of cancer progression. Immunohistochemical analysis of alpha(v)beta(6) expression in 10 human tumor types showed increased expression relative to normal tissues. Squamous carcinomas of the cervix, skin, esophagus, and head and neck exhibited the highest frequency of expression, with positive immunostaining in 92% (n = 46), 84% (n = 49), 68% (n = 56), and 64% (n = 100) of cases, respectively. We studied the role of alpha(v)beta(6) in Detroit 562 human pharyngeal carcinoma cells in vitro and in vivo. Prominent alpha(v)beta(6) expression was detected on tumor xenografts at the tumor-stroma interface resembling the expression on human head and neck carcinomas. Nonetheless, coculturing cells in vitro with matrix proteins did not up-regulate alpha(v)beta(6) expression. Detroit 562 cells showed alpha(v)beta(6)-dependent adhesion and activation of transforming growth factor-beta (TGF-beta) that was inhibited >90% with an alpha(v)beta(6) blocking antibody, 6.3G9. Although both recombinant soluble TGF-beta receptor type-II (rsTGF-beta RII-Fc) and 6.3G9 inhibited TGF-beta-mediated Smad2/3 phosphorylation in vitro, there was no effect on proliferation. Conversely, in vivo, 6.3G9 and rsTGF-beta RII-Fc inhibited xenograft tumor growth by 50% (n = 10, P < 0.05) and >90% (n = 10, P < 0.001), respectively, suggesting a role for the microenvironment in this response. However, stromal collagen and smooth muscle actin content in xenograft sections were unchanged with treatments. Although further studies are required to consolidate in vitro and in vivo results and define the mechanisms of tumor inhibition by alpha(v)beta(6) antibodies, our findings support a role for alpha(v)beta(6) in human cancer and underscore the therapeutic potential of function blocking alpha(v)beta(6) antibodies.

  19. Dynamics of circulating hypoxia-mediated miRNAs and tumor response in patients with high-grade glioma treated with bevacizumab.

    PubMed

    Siegal, Tali; Charbit, Hanna; Paldor, Iddo; Zelikovitch, Bracha; Canello, Tamar; Benis, Arriel; Wong, Michael L; Morokoff, Andrew P; Kaye, Andrew H; Lavon, Iris

    2016-10-01

    OBJECTIVE Bevacizumab is an antiangiogenic agent under investigation for use in patients with high-grade glioma. It produces a high rate of radiological response; however, this response should be interpreted with caution because it may reflect normalization of the tumor vasculature and not necessarily a true antitumor effect. The authors previously demonstrated that 4 hypoxia-mediated microRNAs (miRNA)-miR-210, miR-21, miR-10b, and miR-196b-are upregulated in glioma as compared with normal brain tissue. The authors hypothesized that the regulation and expression of these miRNAs would be altered in response to bevacizumab treatment. The object of this study was to perform longitudinal monitoring of circulating miRNA levels in patients undergoing bevacizumab treatment and to correlate it with tumor response. METHODS A total of 120 serum samples from 28 patients with high-grade glioma were prospectively collected prior to bevacizumab (n = 15) or temozolomide (TMZ; n = 13) treatment and then longitudinally during treatment. Quantification of the 4 miRNAs was evaluated by real-time polymerase chain reaction using total RNA extracted from the serum. At each time point, tumor response was assessed by Response Assessment in Neuro-Oncology criteria and by performing MRI using fluid attenuated inversion recovery (FLAIR) and contrast-enhanced images. RESULTS As compared with pretreatment levels, high levels of miR-10b and miR-21 were observed in the majority of patients throughout the bevacizumab treatment period. miR-10b and miR-21 levels correlated negatively and significantly with changes in enhancing tumor diameters (r = -0.648, p < 0.0001) in the bevacizumab group but not in the TMZ group. FLAIR images and the RANO assessment did not correlate with the sum quantification of these miRNAs in either group. CONCLUSIONS Circulating levels of miR-10b and miR-21 probably reflect the antiangiogenic effect of therapy, but their role as biomarkers for tumor response remains

  20. Epstein-Barr virus in tumor-infiltrating B cells of myasthenia gravis thymoma: an innocent bystander or an autoimmunity mediator?

    PubMed Central

    Cavalcante, Paola; Marcuzzo, Stefania; Franzi, Sara; Galbardi, Barbara; Maggi, Lorenzo; Motta, Teresio; Ghislandi, Raffaella; Buzzi, Antonella; Spinelli, Luisella; Novellino, Lorenzo; Baggi, Fulvio; Antozzi, Carlo; Conforti, Fabio; De Pas, Tommaso Martino; Barberis, Massimo; Bernasconi, Pia; Mantegazza, Renato

    2017-01-01

    The thymus plays a key role in myasthenia gravis (MG), a B cell-mediated autoimmune disorder affecting neuromuscular junction. Most MG patients have thymic abnormalities, including hyperplasia and thymoma, a neoplasm of thymic epithelial cells. Epstein-Barr virus (EBV) is associated with autoimmune diseases and tumors. Recently, we showed EBV persistence and reactivation in hyperplastic MG thymuses, suggesting that EBV might contribute to intra-thymic B cell dysregulation in MG patients. Here, we investigated EBV involvement in thymoma-associated MG, by searching for EBV markers in MG (n=26) and non-MG (n=14) thymomas. EBV DNA and EBV-encoded small nuclear RNA (EBER) 1 transcript were detected in 14/26 (53.8%) and 22/26 (84.6%) MG thymomas, and only in 3 of 14 (21.4%) non-MG thymomas. Latent EBNA2 and late gp350/220 lytic transcripts were undetectable in all, but one, thymomas, and early lytic BZLF1 transcript was absent in all samples, suggesting that early infection events and EBV reactivation were very rare in thymomas. EBER1 and 2-positive cells were detected in MG, but not in non-MG, thymomas, as well as cells expressing EBV latency proteins (EBNA1, LMP1, LMP2A), that were mainly of B cell phenotype, indicating EBV association with MG rather than with thymoma. Toll-like receptor (TLR) 3 transcriptional levels were higher in MG than non-MG thymomas and positively correlated with EBER1 levels, suggesting a role for EBERs in TLR3 activation. Our findings show that EBV is commonly present in thymoma-infiltrating B cells of myasthenic patients, indicating a contribution of EBV to B cell-mediated autoreactivity in MG associated with thymic tumor. PMID:29221139

  1. Induction of p21(WAF1/CIP1) and inhibition of Cdk2 mediated by the tumor suppressor p16(INK4a).

    PubMed

    Mitra, J; Dai, C Y; Somasundaram, K; El-Deiry, W S; Satyamoorthy, K; Herlyn, M; Enders, G H

    1999-05-01

    The tumor suppressor p16(INK4a) inhibits cyclin-dependent kinases 4 and 6. This activates the retinoblastoma protein (pRB) and, through incompletely understood events, arrests the cell division cycle. To permit biochemical analysis of the arrest, we generated U2-OS osteogenic sarcoma cell clones in which p16 transcription could be induced. In these clones, binding of p16 to cdk4 and cdk6 abrogated binding of cyclin D1, p27(KIP1), and p21(WAF1/CIP1). Concomitantly, the total cellular level of p21 increased severalfold via a posttranscriptional mechanism. Most cyclin E-cdk2 complexes associated with p21 and became inactive, expression of cyclin A was curtailed, and DNA synthesis was strongly inhibited. Induction of p21 alone, in a sibling clone, to the level observed during p16 induction substantially reproduced these effects. Overexpression of either cyclin E or A prevented p16 from mediating arrest. We then extended these studies to HCT 116 colorectal carcinoma cells and a p21-null clone derived by homologous recombination. In the parental cells, p16 expression also augmented total cellular and cdk2-bound p21. Moreover, p16 strongly inhibited DNA synthesis in the parental cells but not in the p21-null derivative. These findings indicate that p21-mediated inhibition of cdk2 contributes to the cell cycle arrest imposed by p16 and is a potential point of cooperation between the p16/pRB and p14(ARF)/p53 tumor suppressor pathways.

  2. Down-regulation of RBP-J mediated by microRNA-133a suppresses dendritic cells and functions as a potential tumor suppressor in osteosarcoma.

    PubMed

    Gao, Xuren; Han, Dong; Fan, Weimin

    2016-12-10

    In recent years, immunotherapy for the treatment of tumors have been established. Dendritic cells (DCs) are extremely efficient and professional antigen presenting cells (APCs), which are an important target for immune therapeutic interventions in cancer. In present study, we investigated whether RBP-J signaling regulated by miR-133a was involved in the DCs mediated tumor suppressor in osteosarcoma. DCs were isolated from 30 osteosarcoma patients and 30 healthy subjects. Mouse macrophage-like cell line RAW264.7 were cultured and osteosarcoma mouse model with injection of murine osteosarcoma cell line S180 were established. In osteosarcoma patients, miR-133a expression level of DCs was increased, and RBP-J expression in mRNA and protein levels were decreased. MiR-133a inhibitor promoted maturation and activation of DCs in osteosarcoma patients. In osteosarcoma mouse model, miR-133a mimic suppressed the maturation and activation of spleen DCs, while miR-133a inhibitor promoted them. Overexpression of miR-133a decreased therapeutic effect of DCs on osteosarcoma mice. In RAW264.7 cells, miR-133a was observed to target RBP-J and regulate its expression. MiR-133a mimic inhibited the maturation of DCs in cells exposed to LPS, the effect of which was reversed by overexpression of RBP-J. RBP-J mediated by miR-133a probably contributed to the regulation of DCs maturation and activation in osteosarcoma, which functioned as a therapeutic target for the immunotherapy in cancers. Copyright © 2016. Published by Elsevier Inc.

  3. Hypoxia pathway and hypoxia-mediated extensive extramedullary hematopoiesis are involved in ursolic acid's anti-metastatic effect in 4T1 tumor bearing mice.

    PubMed

    Gao, Jian-Li; Shui, Yan-Mei; Jiang, Wei; Huang, En-Yi; Shou, Qi-Yang; Ji, Xin; He, Bai-Cheng; Lv, Gui-Yuan; He, Tong-Chuan

    2016-11-01

    Hypoxic in the tumor mass is leading to the myeloproliferative-like disease (leukemoid reaction) and anemia of body, which characterized by strong extensive extramedullary hematopoiesis (EMH) in spleen. As the key transcription factor of hypoxia, hypoxia-inducible factor-1 (HIF-1) activates the expression of genes essential for EMH processes including enhanced blood cell production and angiogenesis. We found ursolic acid (UA), a natural pentacyclic triterpenoid carboxylic acid, inhibited growth of breast cancer both in vivo and in vitro. The suppression was mediated through the inhibition of multiple cell pathways linked to inflammation, proliferation, angiogenesis, and metastasis. UA also suppressed the leukemoid reaction and the EMH phenomenon of the tumor bearing mice without any significant suppression on body weight (i.p. by 20 mg/kg for 28 days). This is associated with the significant decrease in white blood cells (WBC), platelets (PLT) and spleen weight. During this process, we also detected the down-regulation of cell proliferative genes (PCNA, and β-catenin), and metastatic genes (VEGF, and HIF-1α), as well as the depression of nuclear protein intensity of HIF-1α. Furthermore, the expression of E2F1, p53 and MDM2 genes were increased in UA group when the VEGF and HIF-1α was over-expressed. Cancer cells were sensitive to UA treating after the silencing of HIF-1α and the response of Hypoxic pathway reporter to UA was suppressed when HIF-1α was over expressed. Overall, our results from experimental and predictive studies suggest that the anticancer activity of UA may be at least in part caused by suppressing the cancer hypoxia and hypoxia-mediated EMH.

  4. Hypoxia pathway and hypoxia-mediated extensive extramedullary hematopoiesis are involved in ursolic acid's anti-metastatic effect in 4T1 tumor bearing mice

    PubMed Central

    Gao, Jian-Li; Shui, Yan-Mei; Jiang, Wei; Huang, En-Yi; Shou, Qi-Yang; Ji, Xin; He, Bai-Cheng; Lv, Gui-Yuan; He, Tong-Chuan

    2016-01-01

    Hypoxic in the tumor mass is leading to the myeloproliferative-like disease (leukemoid reaction) and anemia of body, which characterized by strong extensive extramedullary hematopoiesis (EMH) in spleen. As the key transcription factor of hypoxia, hypoxia-inducible factor-1 (HIF-1) activates the expression of genes essential for EMH processes including enhanced blood cell production and angiogenesis. We found ursolic acid (UA), a natural pentacyclic triterpenoid carboxylic acid, inhibited growth of breast cancer both in vivo and in vitro. The suppression was mediated through the inhibition of multiple cell pathways linked to inflammation, proliferation, angiogenesis, and metastasis. UA also suppressed the leukemoid reaction and the EMH phenomenon of the tumor bearing mice without any significant suppression on body weight (i.p. by 20 mg/kg for 28 days). This is associated with the significant decrease in white blood cells (WBC), platelets (PLT) and spleen weight. During this process, we also detected the down-regulation of cell proliferative genes (PCNA, and β-catenin), and metastatic genes (VEGF, and HIF-1α), as well as the depression of nuclear protein intensity of HIF-1α. Furthermore, the expression of E2F1, p53 and MDM2 genes were increased in UA group when the VEGF and HIF-1α was over-expressed. Cancer cells were sensitive to UA treating after the silencing of HIF-1α and the response of Hypoxic pathway reporter to UA was suppressed when HIF-1α was over expressed. Overall, our results from experimental and predictive studies suggest that the anticancer activity of UA may be at least in part caused by suppressing the cancer hypoxia and hypoxia-mediated EMH. PMID:27708244

  5. Atelocollagen-mediated in vivo siRNA transfection in ovarian carcinoma is influenced by tumor site, siRNA target and administration route

    PubMed Central

    Meryet-Figuière, Matthieu; Lecerf, Charlotte; Varin, Emilie; Coll, Jean-Luc; Louis, Marie-Hélène; Dutoit, Soizic; Giffard, Florence; Blanc-Fournier, Cécile; Hedir, Siham; Vigneron, Nicolas; Brotin, Emilie; Pelletier, Laurent; Josserand, Véronique; Denoyelle, Christophe; Poulain, Laurent

    2017-01-01

    Ovarian cancer is the leading cause of death from gynecological malignancies worldwide, and innate or acquired chemoresistance of ovarian cancer cells is the major cause of therapeutic failure. It has been demonstrated that the concomitant inhibition of Bcl-xL and Mcl-1 anti-apoptotic activities is able to trigger apoptosis in chemoresistant ovarian cancer cells. In this context, siRNA-mediated Bcl-xL and Mcl-1 inhibition constitutes an appealing strategy by which to eliminate chemoresistant cancer cells. However, the safest and most efficient way to vectorize siRNAs in vivo is still under debate. In the present study, using in vivo bioluminescence imaging, we evaluated the interest of atelocollagen to vectorize siRNAs by intraperitoneal (i.p.) or intravenous (i.v.) administration in 2 xenografted ovarian cancer models (peritoneal carcinomatosis and subcutaneous tumors in nude mice). Whereas i.p. administration of atelocollagen-vectorized siRNA in the peritoneal carcinomatosis model did not induce any gene downregulation, a 70% transient downregulation of luciferase expression was achieved after i.v. injection of atelocollagen-vectorized siRNA in the subcutaneous (s.c.) model. However, the use of siRNA targeting Bcl-xL or Mcl-1 did not induce target-specific downregulation in vivo in nude mice. Our results therefore show that atelocollagen complex formulation, the administration route, tumor site and the identity of the siRNA target influence the efficiency of atelocollagen-mediated siRNA delivery. PMID:28791387

  6. CD4+ T cell-mediated cytotoxicity eliminates primary tumor cells in metastatic melanoma through high MHC class II expression and can be enhanced by inhibitory receptor blockade.

    PubMed

    Yan, Hongxia; Hou, Xianglian; Li, Tianhang; Zhao, Li; Yuan, Xiaozhou; Fu, Hongjun; Zhu, Ruijie

    2016-10-05

    Metastatic melanoma is a rapidly progressing disease with high mortality rate and limited treatment options. Immunotherapy based on tumor-targeting cytotoxic T cell responses represents a promising strategy. To assist in its development, we examined the possibility and efficacy of using CD4 + cytotoxic T cells. The regulatory mechanisms controlling CD4 + T cell-mediated cytotoxicity were also investigated. We found that naturally occurring granzyme B and perforin-expressing CD4 + cytotoxic T cells can be recovered from metastatic melanoma patients at significantly elevated frequencies compared to those from healthy controls. These CD4 + cytotoxic T cells were also capable of killing autologous tumor cells harvested from metastatic melanoma, independent of CD8 + T cells or any other cell types. However, several restricting factors were observed. First, the cytolytic activity by CD4 + T cells required high MHC class II expression on melanoma cells, which was not satisfied in a subset of melanomas. Second, the granzyme B and perforin release by activated CD4 + cytotoxic T cells was reduced after coculturing with autologous melanoma cells, characterized by low LAMP-1 expression and low granzyme B and perforin secretion in the supernatant. This suggested that inhibitory mechanisms were present to suppress CD4 + cytotoxic T cells. Indeed, blockade of PD-1 and CTLA-4 had increased the cytolytic activity of CD4 + T cells but was only effective in MHC class II high but not MHC class II low melanomas. Together, our study showed that CD4 + T cell-mediated cytotoxicity could eliminate primary melanoma cells but the efficacy depended on MHC class II expression.

  7. Thyroid tumor formation in the male mouse induced by fluopyram is mediated by activation of hepatic CAR/PXR nuclear receptors.

    PubMed

    Rouquié, D; Tinwell, H; Blanck, O; Schorsch, F; Geter, D; Wason, S; Bars, R

    2014-12-01

    Fluopyram, a broad spectrum fungicide, caused an increased incidence of thyroid follicular cell (TFC) adenomas in males at the highest dose evaluated (750ppm equating to 105mg/kg/day) in the mouse oncogenicity study. A series of short-term mechanistic studies were conducted in the male mouse to characterize the mode of action (MOA) for the thyroid tumor formation and to determine if No Observed Effect Levels (NOELs) exist for each key event identified. The proposed MOA consists of an initial effect on the liver by activating the constitutive androstane (Car) and pregnane X (Pxr) nuclear receptors causing increased elimination of thyroid hormones followed by an increased secretion of thyroid stimulating hormone (TSH). This change in TSH secretion results in an increase of TFC proliferation which leads to hyperplasia and eventually adenomas after chronic exposure. Car/Pxr nuclear receptors were shown to be activated as indicated by increased activity of specific Phase I enzymes (PROD and BROD, respectively). Furthermore, evidence of increased T4 metabolism was provided by the induction of phase II enzymes known to preferentially use T4 as a substrate. Additional support for the proposed MOA was provided by demonstrating increased Tsh β transcripts in the pituitary gland. Finally, increased TFC proliferation was observed after 28days of treatment. In these dose-response studies, clear NOELs were established for phase 2 liver enzyme activities, TSH changes and TFC proliferation. Furthermore, compelling evidence for Car/Pxr activation being the molecular initiating event for these thyroid tumors was provided by the absence of the sequential key events responsible for the TCF tumors in Car/Pxr KO mice when exposed to fluopyram. In conclusion, fluopyram thyroid toxicity is mediated by activation of hepatic Car/Pxr receptors and shows a threshold dependent MOA. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. CYP2F2-generated metabolites, not styrene oxide, are a key event mediating the mode of action of styrene-induced mouse lung tumors.

    PubMed

    Cruzan, G; Bus, J; Hotchkiss, J; Harkema, J; Banton, M; Sarang, S

    2012-02-01

    Styrene induces lung tumors in mice but not in rats. Although metabolism of styrene to 7,8-styrene oxide (SO) by CYP2E1 has been suggested as a mediator of styrene toxicity, lung toxicity is not attenuated in CYP2E1 knockout mice. However, styrene and/or SO metabolism by mouse lung Clara cell-localized CYP2F2 to ring-oxidized cytotoxic metabolite(s) has been postulated as a key metabolic gateway responsible for both lung toxicity and possible tumorigenicity. To test this hypothesis, the lung toxicity of styrene and SO was evaluated in C57BL/6 (WT) and CYP2F2⁻/⁻ knockout mice treated with styrene (400 mg/kg/day, gavage, or 200 or 400 mg/kg/day, ip) or S- or R-SO (200 mg/kg/day, ip) for 5 days. Styrene treated WT mice displayed significant necrosis and exfoliation of Clara cells, and cumulative BrdU-labeling index of S-phase cells was markedly increased in terminal bronchioles of WT mice exposed to styrene or S- or RSO. In contrast, Clara and terminal bronchiole cell toxicity was not observed in CYP2F2⁻/⁻ mice exposed to either styrene or SO. This study clearly demonstrates that the mouse lung toxicity of both styrene and SO is critically dependent on metabolism by CYP2F2. Importantly, the human isoform of CYP2F, CYP2F1, is expressed at much lower levels and likely does not catalyze significant styrene metabolism, supporting the hypothesis that styrene-induced mouse lung tumors may not quantitatively, or possibly qualitatively, predict lung tumor potential in humans. Copyright © 2011 Elsevier Inc. All rights reserved.

  9. Neutrophils control the magnitude and spread of the immune response in a thromboxane A2-mediated process

    PubMed Central

    Yang, Chiao-Wen

    2013-01-01

    Neutrophils are obligate cells entering lymph nodes shortly after immunization with protein antigens in adjuvants, starting during the first hour and continuing for several days in two distinct waves. Previously, we demonstrated the strong suppressive effects of neutrophils on CD4 T cell and B cell responses, using either neutrophil-depleting antibodies or genetically neutropenic mice. In this study, we find that neutrophils are the major cells controlling the spread of T cell responses to distal lymph nodes. Although in the presence of neutrophils, ∼75% of the response was restricted to the draining node, in their absence, most of the response was found in distal nodes. Prostanoids were responsible for the rapid entry of neutrophils into the draining nodes, as well as for the two distinct neutrophil effects: the modulation of the magnitude of the cellular response, and in its spread outside the draining nodes. Neutrophil-produced thromboxane A2 was the key eicosanoid controlling both effects. Adoptive transfer of neutrophils into mice genetically deficient in neutrophils indicated their role in both. These functions of neutrophils are important in infections and vaccinations with adjuvants where neutrophils are abundant in the initial stages. PMID:23337807

  10. Peroxisome Proliferator-activated Receptor-α-mediated Transcription of miR-199a2 Attenuates Endothelin-1 Expression via Hypoxia-inducible Factor-1α*

    PubMed Central

    Li, Chen; Mpollo, Marthe-Sandrine Eiymo Mwa; Gonsalves, Caryn S.; Tahara, Stanley M.; Malik, Punam; Kalra, Vijay K.

    2014-01-01

    Endothelin-1, a potent vasoconstrictor, plays an important role in pulmonary hypertension (PH) in sickle cell disease (SCD). Our previous studies show that higher levels of placenta growth factor (PlGF), secreted by erythroid precursor cells, correlate with increased plasma levels of endothelin-1 (ET-1) and other functional markers of PH in SCD. PlGF-mediated ET-1 expression occurs via activation of hypoxia-inducible factor-1α (HIF-1α). However, relatively less is understood regarding how PlGF-mediated expression of HIF-1α and its downstream effector ET-1 are post-transcriptionally regulated. Herein, we show that PlGF treatment of endothelial cells resulted in reduced levels of miR-199a2, which targeted the 3′-UTR of HIF-1α mRNA and concomitantly led to augmented ET-1 expression. Plasma levels of miR-199a2 in SCD subjects were significantly lower with reciprocally high levels of plasma ET-1, unlike unaffected controls. This observation provided a molecular link between miR-199a2 and high levels of ET-1 in SCD. Furthermore, we show that miR-199a2 located in the DNM3os transcription unit was co-transcriptionally regulated by peroxisome proliferator-activated receptor α (PPARα). Binding of the latter to PPARα cis-elements in the promoter of DNM3os was demonstrated by promoter mutational analysis and ChIP. Additionally, we show that fenofibrate, a PPARα agonist, increased the expression of miR-199a2 and DNM3os; the former was responsible for reduced expression of HIF-1α and ET-1. In vivo studies of fenofibrate-fed Berkeley sickle mice resulted in increased levels of miR-199a2 and reduced levels of ET-1 in lung tissues. Our studies provide a potential therapeutic approach whereby fenofibrate-induced miR-199a2 expression can ameliorate PH by reduction of ET-1 levels. PMID:25389292

  11. Human MHC Class I-restricted high avidity CD4+ T cells generated by co-transfer of TCR and CD8 mediate efficient tumor rejection in vivo

    PubMed Central

    Xue, Shao-An; Gao, Liquan; Ahmadi, Maryam; Ghorashian, Sara; Barros, Rafael D; Pospori, Constandina; Holler, Angelika; Wright, Graham; Thomas, Sharyn; Topp, Max; Morris, Emma C; Stauss, Hans J.

    2013-01-01

    In this study, we generated human MHC Class I-restricted CD4+ T cells specific for Epstein-Barr virus (EBV) and cytomegalovirus (CMV), two herpesviridae associated with lymphoma, nasopharyngeal carcinoma and medulloblastoma, respectively. Retroviral transfer of virus-specific, HLA-A2-restricted TCR-coding genes generated CD4+ T cells that recognized HLA-A2/peptide multimers and produced cytokines when stimulated with MHC Class II-deficient cells presenting the relevant viral peptides in the context of HLA-A2. Peptide titration revealed that CD4+ T cells had a 10-fold lower avidity than CD8+ T cells expressing the same TCR. The impaired avidity of CD4+ T cells was corrected by simultaneously transferring TCR- and CD8-coding genes. The CD8 co-receptor did not alter the cytokine signature of CD4+ T cells, which remained distinct from that of CD8+ T cells. Using the xenogeneic NOD/SCID mouse model, we demonstrated that human CD4+ T cells expressing a specific TCR and CD8 can confer efficient protection against the growth of tumors expressing the EBV or CMV antigens recognized by the TCR. In summary, we describe a robust approach for generating therapeutic CD4+ T cells capable of providing MHC Class I-restricted immunity against MHC Class II-negative tumors in vivo. PMID:23483821

  12. ARRB1-Mediated Regulation of E2F Target Genes in Nicotine-Induced Growth of Lung Tumors

    PubMed Central

    Dasgupta, Piyali; Rizwani, Wasia; Pillai, Smitha; Davis, Rebecca; Banerjee, Sarmistha; Hug, Kevin; Lloyd, Mark; Coppola, Domenico; Haura, Eric

    2011-01-01

    Background Nicotine induces the proliferation of non–small cell lung cancer (NSCLC) cells via nicotinic acetylcholine receptors and the arrestin, β1 (ARRB1) protein. However, whether ARRB1 translocates to the nucleus upon nicotinic acetylcholine receptor activation and how it regulates growth of human NSCLCs are not known. Methods We investigated nuclear localization of ARRB1 in human NSCLC cell lines (A549 and H1650), normal lung cell lines (NHBE and SAEC), and lung cancer tissue microarray. A549 cells were transfected with ARRB1-specific short hairpin RNA (A549-sh) to knockdown ARRB1 expression, or with empty vector (A549-EV), to examine the role of ARRB1 in the mitogenic and antiapoptotic effects of nicotine, binding of ARRB1 to E2F transcription factors, and the role of ARRB1 in nicotine-induced expression of E2F-regulated survival and proliferative genes cell division cycle 6 homolog (CDC6), thymidylate synthetase (TYMS), and baculoviral IAP repeat–containing 5 (BIRC5). Real-time polymerase chain reaction was performed for quantitative analysis of mRNA expression. Chromatin immunoprecipitation assays were performed on A549 cells and fresh-frozen human NSCLC tumors (n = 8) to examine the binding of ARRB1, E1A binding protein (EP300), and acetylated histone 3 (Ac-H3) on the E2F-regulated genes. All statistical tests were two-sided. Results Nicotine induced the nuclear translocation of ARRB1 in NSCLC and normal lung cells, and lung tumor tissues from smokers showed an increased nuclear localization. The mitogenic and antiapoptotic effects of nicotine were reduced in A549-sh cells. Nuclear ARRB1 bound to E2F transcription factors in normal lung cells, NSCLC cells, and tumors. Nicotine treatment induced a statistically significant increased expression of E2F-regulated genes in A549-EV but not in A549-sh cells; the maximum difference being observed in BIRC5 (A549-EV vs A549-sh, mean fold-increase in mRNA level upon nicotine treatment = 20.7-fold, 95% confidence

  13. Curcumin exhibits anti-tumor effect and attenuates cellular migration via Slit-2 mediated down-regulation of SDF-1 and CXCR4 in endometrial adenocarcinoma cells.

    PubMed

    Sirohi, Vijay Kumar; Popli, Pooja; Sankhwar, Pushplata; Kaushal, Jyoti Bala; Gupta, Kanchan; Manohar, Murli; Dwivedi, Anila

    2017-06-01

    Although curcumin shows anti-proliferative and anti-inflammatory activities in various cancers, the effect of curcumin on cellular migration in endometrial adenocarcinoma cells remains to be understood. The current investigation was aimed to explore the anti-proliferative and anti-migratory effects of curcumin and its mechanism of action in endometrial cancer cells. Our in-vitro and in-vivo experimental studies showed that curcumin inhibited the proliferation of endometrial cancer cells and suppressed the tumor growth in Ishikawa xenograft mouse model. Curcumin induced ROS-mediated apoptosis in endometrial cancer cells. Curcumin suppressed the migration rate of Ishikawa and Hec-1B cells as analyzed by scratch wound assay. In transwell migration studies, knock down of Slit-2 reversed the anti-migratory effect of curcumin in these cell lines. Curcumin significantly up-regulated the expression of Slit-2 in Ishikawa, Hec-1B and primary endometrial cancer cells while it down-regulated the expression of stromal cell-derived factor-1 (SDF-1) and CXCR4 which in turn, suppressed the expression of matrix metallopeptidases (MMP) 2 and 9, thus attenuating the migration of endometrial cancer cells. In summary, we have demonstrated that curcumin has inhibitory effect on cellular migration via Slit-2 mediated down-regulation of CXCR4, SDF-1, and MMP2/MMP9 in endometrial carcinoma cells. These findings helped explore the role of Slit-2 in endometrial cancer cells. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Andrographolide induces apoptotic and non-apoptotic death and enhances tumor necrosis factor-related apoptosis-inducing ligand-mediated apoptosis in gastric cancer cells.

    PubMed

    Lim, Sung-Chul; Jeon, Ho Jong; Kee, Keun Hong; Lee, Mi Ja; Hong, Ran; Han, Song Iy

    2017-05-01

    Andrographolide, a natural compound isolated from Andrographis paniculata , has been reported to possess antitumor activity. In the present study, the effect of andrographolide in human gastric cancer (GC) cells was investigated. Andrographolide induced cell death with apoptotic and non-apoptotic features. At a low concentration, andrographolide potentiated apoptosis and reduction of clonogenicity triggered by recombinant human tumor necrosis factor-related apoptosis-inducing ligand (rhTRAIL). Exposure of GC cells to andrographolide altered the expression level of several growth-inhibiting and apoptosis-regulating proteins, including death receptors. It was demonstrated that activity of the TRAIL-R2 (DR5) pathway was critical in the development of andrographolide-mediated rhTRAIL sensitization, since its inhibition significantly reduced the extent of apoptosis induced by the combination of rhTRAIL and andrographolide. In addition, andrographolide increased reactive oxygen species (ROS) generation in a dose-dependent manner. N-acetyl cysteine prevented andrographolide-mediated DR5 induction and the apoptotic effect induced by the combination of rhTRAIL and andrographolide. Collectively, the present study demonstrated that andrographolide enhances TRAIL-induced apoptosis through induction of DR5 expression. This effect appears to involve ROS generation in GCs.

  15. The tumor suppressor gene WWOX links the canonical and noncanonical NF-κB pathways in HTLV-I Tax-mediated tumorigenesis

    PubMed Central

    Fu, Jing; Qu, Zhaoxia; Yan, Pengrong; Ishikawa, Chie; Aqeilan, Rami I.; Rabson, Arnold B.

    2011-01-01

    Both the canonical and noncanonical nuclear factor κB (NF-κB) pathways have been linked to tumorigenesis. However, it remains unknown whether and how the 2 signaling pathways cooperate during tumorigenesis. We report that inhibition of the noncanonical NF-κB pathway significantly delays tumorigenesis mediated by the viral oncoprotein Tax. One function of noncanonical NF-κB activation was to repress expression of the WWOX tumor suppressor gene. Notably, WWOX specifically inhibited Tax-induced activation of the canonical, but not the noncanonical NF-κB pathway. Mechanistic studies indicated that WWOX blocked Tax-induced inhibitors of κB kinaseα (IKKα) recruitment to RelA and subsequent RelA phosphorylation at S536. In contrast, WWOX Y33R, a mutant unable to block the IKKα recruitment and RelA phosphorylation, lost the ability to inhibit Tax-mediated tumorigenesis. These data provide one important mechanism by which Tax coordinates the 2 NF-κB pathways for tumorigenesis. These data also suggest a novel role of WWOX in NF-κB regulation and viral tumorigenesis. PMID:21115974

  16. INPP4B-mediated tumor resistance is associated with modulation of glucose metabolism via hexokinase 2 regulation in laryngeal cancer cells

    SciTech Connect

    Min, Joong Won; Kim, Kwang Il; Kim, Hyun-Ah

    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 andmore » 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.« less

  17. The ancient cytokine IL-17D is regulated by Nrf2 and mediates tumor and virus surveillance.

    PubMed

    Seelige, Ruth; Washington, Allen; Bui, Jack D

    2017-03-01

    Early stage immune responses can dictate the severity and outcome of inflammatory processes such as tumor growth and viral infection. Cytokines such as the interleukin 17 (IL-17) family and cellular stress defense (e.g., anti-oxidant) pathways have evolved early and regulate disease surveillance in vertebrates and invertebrates as far back as Caenorhabditis elegans. Our group has recently found a new role for nuclear factor erythroid-derived 2-like 2 (Nrf2) in regulating early anti-cancer immune responses by inducing IL-17D and recruiting natural killer (NK) cells. In this Cytokine Stimulus, we discuss recent findings that encourage boosting the Nrf2/IL-17D/NK cell axis for the treatment of cancer and viral infection. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Cambrian origin of the CYP27C1-mediated vitamin A1-to-A2switch, a key mechanism of vertebrate sensory plasticity.

    PubMed

    Morshedian, Ala; Toomey, Matthew B; Pollock, Gabriel E; Frederiksen, Rikard; Enright, Jennifer M; McCormick, Stephen D; Cornwall, M Carter; Fain, Gordon L; Corbo, Joseph C

    2017-07-01

    The spectral composition of ambient light varies across both space and time. Many species of jawed vertebrates adapt to this variation by tuning the sensitivity of their photoreceptors via the expression of CYP27C1, an enzyme that converts vitamin A 1 into vitamin A 2 , thereby shifting the ratio of vitamin A 1 -based rhodopsin to red-shifted vitamin A 2 -based porphyropsin in the eye. Here, we show that the sea lamprey ( Petromyzon marinus ), a jawless vertebrate that diverged from jawed vertebrates during the Cambrian period (approx. 500 Ma), dynamically shifts its photoreceptor spectral sensitivity via vitamin A 1 -to-A 2 chromophore exchange as it transitions between photically divergent aquatic habitats. We further show that this shift correlates with high-level expression of the lamprey orthologue of CYP27C1, specifically in the retinal pigment epithelium as in jawed vertebrates. Our results suggest that the CYP27C1-mediated vitamin A 1 -to-A 2 switch is an evolutionarily ancient mechanism of sensory plasticity that appeared not long after the origin of vertebrates.

  19. Cambrian origin of the CYP27C1-mediated vitamin A1-to-A2 switch, a key mechanism of vertebrate sensory plasticity

    USGS Publications Warehouse

    Morshedian, Ala; Toomery, Matthew B.; Pollock, Gabriel E.; Frederiksen, Rikard; Enright, Jennifer; McCormick, Stephen; Cornwall, M. Carter; Fain, Gordon L.; Corbo, Joseph C.

    2017-01-01

    The spectral composition of ambient light varies across both space and time. Many species of jawed vertebrates adapt to this variation by tuning the sensitivity of their photoreceptors via the expression of CYP27C1, an enzyme that converts vitamin A1 into vitamin A2, thereby shifting the ratio of vitamin A1-based rhodopsin to red-shifted vitamin A2-based porphyropsin in the eye. Here, we show that the sea lamprey (Petromyzon marinus), a jawless vertebrate that diverged from jawed vertebrates during the Cambrian period (approx. 500 Ma), dynamically shifts its photoreceptor spectral sensitivity via vitamin A1-to-A2 chromophore exchange as it transitions between photically divergent aquatic habitats. We further show that this shift correlates with high-level expression of the lamprey orthologue of CYP27C1, specifically in the retinal pigment epithelium as in jawed vertebrates. Our results suggest that the CYP27C1-mediated vitamin A1-to-A2 switch is an evolutionarily ancient mechanism of sensory plasticity that appeared not long after the origin of vertebrates.

  20. The effect of caffeine to increase reaction time in the rat during a test of attention is mediated through antagonism of adenosine A2A receptors.

    PubMed

    Higgins, Guy A; Grzelak, Michael E; Pond, Annamarie J; Cohen-Williams, Mary E; Hodgson, Robert A; Varty, Geoffrey B

    2007-12-11

    Caffeine produces effects on cognitive function particularly relating to aspects of attention such as reaction time. Considering the plasma exposure levels following regular caffeine intake, and the affinity of caffeine for known protein targets, these effects are likely mediated by either the adenosine A(1) or A(2A) receptor. In the present studies, two rat strains [Long-Evans (LE) and CD] were trained to asymptote performance in a test of selective attention, the 5-choice serial reaction time task (5-CSRTT). Next, the effects of caffeine were compared to the selective A(2A) antagonists, SCH 412348 and KW-6002 (Istradefylline), and the A(1) antagonist, DPCPX. Further studies compared the psychostimulant effects of each drug. Finally, we tested the A(2A) agonist, CGS-21680, on 5-CSRTT performance and given the antipsychotic potential of this drug class, studied the interaction between CGS-21680 and amphetamine in this task. Caffeine (3-10mg/kg IP) increased reaction time in both LE and CD rats, with no effect on accuracy, an effect replicated by SCH 412348 (0.1-1mg/kg PO) and KW-6002 (1-3mg/kg PO), but not DPCPX (3-30 mg/kg PO). At least with SCH 412348, these effects were at doses that were not overtly psychostimulant. In contrast, CGS-21680 (0.03-0. 3mg/kg IP) slowed reaction speed and increased omissions. Interestingly, at a comparatively low dose of 0.03 mg/kg, CGS-21680 attenuated the increased premature responding produced by amphetamine (1mg/kg IP). The present results suggest that the attention-enhancing effects of caffeine are mediated through A(2A) receptor blockade, and selective A(2A) receptor antagonists may have potential as therapies for attention-related disorders. Furthermore, the improvement in response control in amphetamine-treated rats following CGS-21680 pretreatment supports the view that A(2A) agonists have potential as novel antipsychotics.

  1. A2B adenosine receptor contributes to penile erection via PI3K/AKT signaling cascade-mediated eNOS activation

    PubMed Central

    Wen, Jiaming; Grenz, Almut; Zhang, Yujin; Dai, Yingbo; Kellems, Rodney E.; Blackburn, Michael R.; Eltzschig, Holger K.; Xia, Yang

    2011-01-01

    Normal penile erection is under the control of multiple factors and signaling pathways. Although adenosine signaling is implicated in normal and abnormal penile erection, the exact role and the underlying mechanism for adenosine signaling in penile physiology remain elusive. Here we report that shear stress leads to increased adenosine release from endothelial cells. Subsequently, we determined that ecto-5′-nucleotidase (CD73) is a key enzyme required for the production of elevated adenosine from ATP released by shear-stressed endothelial cells. Mechanistically, we demonstrate that shear stress-mediated elevated adenosine functions through the adenosine A2B receptor (A2BR) to activate the PI3K/AKT signaling cascade and subsequent increased endothelial nitric oxide synthase (eNOS) phosphorylation. These in vitro studies led us to discover further that adenosine was induced during sustained penile erection and contributes to PI3K/AKT activation and subsequent eNOS phosphorylation via A2BR signaling in intact animal. Finally, we demonstrate that lowering adenosine in wild-type mice or genetic deletion of A2BR in mutant mice significantly attenuated PI3K/AKT activation, eNOS phosphorylation, and subsequent impaired penile erection featured with the reduction of ratio of maximal intracavernosal pressure to systemic arterial pressure from 0.49 ± 0.03 to 0.41 ± 0.05 and 0.38 ± 0.04, respectively (both P<0.05). Overall, using biochemical, cellular, genetic, and physiological approaches, our findings reveal that adenosine is a novel molecule signaling via A2BR activation, contributing to penile erection via PI3K/AKT-dependent eNOS activation. These studies suggest that this signaling pathway may be a novel therapeutic target for erectile disorders.—Wen, J., Grenz, A., Zhang, Y., Dai, Y., Kellems, R. E., Blackburn, M. R., Eltzschig, H. K., Xia, Y. A2B adenosine receptor contributes to penile erection via PI3K/AKT signaling cascade-mediated eNOS activation. PMID

  2. Ectopic expression of UGT84A2 delayed flowering by indole-3-butyric acid-mediated transcriptional repression of ARF6 and ARF8 genes in Arabidopsis.

    PubMed

    Zhang, Gui-Zhi; Jin, Shang-Hui; Li, Pan; Jiang, Xiao-Yi; Li, Yan-Jie; Hou, Bing-Kai

    2017-12-01

    Ectopic expression of auxin glycosyltransferase UGT84A2 in Arabidopsis can delay flowering through increased indole-3-butyric acid and suppressed transcription of ARF6, ARF8 and flowering-related genes FT, SOC1, AP1 and LFY. Auxins are critical regulators for plant growth and developmental processes. Auxin homeostasis is thus an important issue for plant biology. Here, we identified an indole-3-butyric acid (IBA)-specific glycosyltransferase, UGT84A2, and characterized its role in Arabidopsis flowering development. UGT84A2 could catalyze the glycosylation of IBA, but not indole-3-acetic acid (IAA). UGT84A2 transcription expression was clearly induced by IBA. When ectopically expressing in Arabidopsis, UGT84A2 caused obvious delay in flowering. Correspondingly, the increase of IBA level, the down-regulation of AUXIN RESPONSE FACTOR 6 (ARF6) and ARF8, and the down-regulation of flowering-related genes such as FLOWERING LOCUS T (FT), SUPPRESSOR OF OVEREXPRESSION OF CO1(SOC1), APETALA1 (AP1), and LEAFY(LFY) were observed in transgenic plants. When exogenously applying IBA to wild-type plants, the late flowering phenotype, the down-regulation of ARF6, ARF8 and flowering-related genes recurred. We examined the arf6arf8 double mutants and found that the expression of flowering-related genes was also substantially decreased in these mutants. Together, our results suggest that glycosyltransferase UGT84A2 may be involved in flowering regulation through indole-3-butyric acid-mediated transcriptional repression of ARF6, ARF8 and downstream flowering pathway genes.

  3. Selective A2A receptor antagonist prevents microglia-mediated neuroinflammation and protects retinal ganglion cells from high intraocular pressure-induced transient ischemic injury.

    PubMed

    Madeira, Maria H; Boia, Raquel; Elvas, Filipe; Martins, Tiago; Cunha, Rodrigo A; Ambrósio, António Francisco; Santiago, Ana Raquel

    2016-03-01

    Glaucoma is a leading cause of vision loss and blindness worldwide, characterized by chronic and progressive neuronal loss. Reactive microglial cells have been recognized as a neuropathologic feature, contributing to local inflammation and retinal neurodegeneration. In a recent in vitro work (organotypic cultures), we demonstrated that blockade of adenosine A2A receptor (A2AR) prevents the neuroinflammatory response and affords protection to retinal ganglion cells (RGCs) against exposure to elevated hydrostatic pressure (EHP), to mimic elevated intraocular pressure (IOP), the main risk factor for glaucoma development. Herein, we investigated whether a selective A2AR antagonist (SCH 58261) could modulate retinal microglia reactivity and their inflammatory response. Furthermore, we took advantage of the high IOP-induced transient ischemia (ischemia-reperfusion, I-R) animal model to evaluate the protective role of A2AR blockade in the control of retinal neuroinflammation and neurodegeneration. Primary microglial cell cultures were challenged either with lipopolysaccharide or with EHP, in the presence or absence of A2AR antagonist SCH 58261 (50 nM). In addition, I-R injury was induced in adult Wistar rats after intravitreal administration of SCH 58261 (100 nM, 5 μL). Our results showed that SCH 58261 attenuated microglia reactivity and the increased expression and release of proinflammatory cytokines. Moreover, intravitreal administration of SCH 58261 prevented I-R-induced cell death and RGC loss, by controlling microglial-mediated neuroinflammatory response. These results prompt the proposal that A2AR blockade may have great potential in the management of retinal neurodegenerative diseases characterized by microglia reactivity and RGC death, such as glaucoma and ischemic diseases. Copyright © 2016 Elsevier Inc. All rights reserved.