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Sample records for natural antitumor resistance

  1. An Update on Antitumor Activity of Naturally Occurring Chalcones

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    En-Hui Zhang

    2013-01-01

    Full Text Available Chalcones, which have characteristic 1,3-diaryl-2-propen-1-one skeleton, are mainly produced in roots, rhizomes, heartwood, leaves, and seeds of genera Angelica, Sophora, Glycyrrhiza, Humulus, Scutellaria, Parartocarpus, Ficus, Dorstenia, Morus, Artocarpus, and so forth. They have become of interest in the research and development of natural antitumor agents over the past decades due to their broad range of mechanisms including anti-initiation, induction of apoptosis, antiproliferation, antimetastasis, antiangiogenesis, and so forth. This review summarizes the studies on the antitumor activity of naturally occurring chalcones and their underlying mechanisms in detail during the past decades.

  2. Neurofibromin 1 Impairs Natural Killer T-Cell-Dependent Antitumor Immunity against a T-Cell Lymphoma

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    Jianyun Liu

    2018-01-01

    Full Text Available Neurofibromin 1 (NF1 is a tumor suppressor gene encoding a Ras GTPase that negatively regulates Ras signaling pathways. Mutations in NF1 are linked to neurofibromatosis type 1, juvenile myelomonocytic leukemia and Watson syndrome. In terms of antitumor immunity, CD1d-dependent natural killer T (NKT cells play an important role in the innate antitumor immune response. Generally, Type-I NKT cells protect (and Type-II NKT cells impair host antitumor immunity. We have previously shown that CD1d-mediated antigen presentation to NKT cells is regulated by cell signaling pathways. To study whether a haploinsufficiency in NF1 would affect CD1d-dependent activation of NKT cells, we analyzed the NKT-cell population as well as the functional expression of CD1d in Nf1+/− mice. Nf1+/− mice were found to have similar levels of NKT cells as wildtype (WT littermates. Interestingly, however, reduced CD1d expression was observed in Nf1+/− mice compared with their WT littermates. When inoculated with a T-cell lymphoma in vivo, Nf1+/− mice survived longer than their WT littermates. Furthermore, blocking CD1d in vivo significantly enhanced antitumor activity in WT, but not in Nf1+/− mice. In contrast, a deficiency in Type-I NKT cells increased antitumor activity in Nf1+/− mice, but not in WT littermates. Therefore, these data suggest that normal NF1 expression impairs CD1d-mediated NKT-cell activation and antitumor activity against a T-cell lymphoma.

  3. Effective photodynamic therapy in drug-resistant prostate cancer cells utilizing a non-viral antitumor vector (a secondary publication).

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    Yamauchi, Masaya; Honda, Norihiro; Hazama, Hisanao; Tachikawa, Shoji; Nakamura, Hiroyuki; Kaneda, Yasufumi; Awazu, Kunio

    2016-03-31

    There is an urgent need to develop an efficient strategy for the treatment of drug-resistant prostate cancer. Photodynamic therapy (PDT), in which low incident levels of laser energy are used to activate a photosensitizer taken up by tumor cells, is expected as a novel therapy for the treatment of prostate cancer because of the minimal invasive nature of PDT. The present study was designed to assess the efficacy of a novel vector approach combined with a conventional porphyrin-based photosensitizer. Our group focused on a non-viral vector (hemagglutinating virus of Japan envelope; HVJ-E) combined with protoporphyrin IX (PpIX) lipid, termed the porphyrus envelope (PE). It has been previously confirmed that HVJ-E has drug-delivering properties and can induce cancer-specific cell death. The PE (HVJ-E contained in PpIX lipid) was developed as a novel photosensitizer. In this study, the antitumor and PDT efficacy of the PE against hormone-antagonistic human prostate cancer cells (PC-3) were evaluated. Our results demonstrated that, under specific circumstances, PDT using the PE was very effective against PC-3 cells. A novel therapy for drug-resistant prostate cancer based on this vector approach is eagerly anticipated.

  4. Circumvention of the multidrug-resistance protein (MRP-1) by an antitumor drug through specific inhibition of gene transcription in breast tumor cells.

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    Mansilla, Sylvia; Rojas, Marta; Bataller, Marc; Priebe, Waldemar; Portugal, José

    2007-04-01

    Multidrug-resistance protein 1 (MRP-1) confers resistance to a number of clinically important chemotherapeutic agents. The promoter of the mrp-1 gene contains an Sp1-binding site, which we targeted using the antitumor bis-anthracycline WP631. When MCF-7/VP breast cancer cells, which overexpress MRP-1 protein, were incubated with WP631 the expression of the multidrug-resistance protein gene decreased. Conversely, doxorubicin did not alter mrp-1 gene expression. The inhibition of gene expression was followed by a decrease in the activity of the MRP-1 protein. The IC(75) for WP631 (drug concentration required to inhibit cell growth by 75%) circumvented the drug-efflux pump, without addition of resistant modifiers. After treatment with WP631, MCF-7/VP cells were committed to die after entering mitosis (mitotic catastrophe), while treatment with doxorubicin did not affect cell growth. This is the first report on an antitumor drug molecule inhibiting the mrp-1 gene directly, rather than being simply a poor substrate for the transporter-mediated efflux. However, both situations appeared to coexist, thereby a superior cytotoxic effect was attained. Ours results suggest that WP631 offers great potential for the clinical treatment of tumors displaying a multidrug-resistance phenotype.

  5. Antitumor effects of cecropin B-LHRH’ on drug-resistant ovarian and endometrial cancer cells

    International Nuclear Information System (INIS)

    Li, Xiaoyong; Shen, Bo; Chen, Qi; Zhang, Xiaohui; Ye, Yiqing; Wang, Fengmei; Zhang, Xinmei

    2016-01-01

    Luteinizing hormone-releasing hormone receptor (LHRHr) represents a promising therapeutic target for treating sex hormone-dependent tumors. We coupled cecropin B, an antimicrobial peptide, to LHRH’, a form of LHRH modified at carboxyl-terminal residues 4–10, which binds to LHRHr without interfering with luteinizing hormone (LH) and follicle-stimulating hormone (FSH) secretion. This study aimed to assess the antitumor effects of cecropin B-LHRH’ (CB-LHRH’) in drug-resistant ovarian and endometrial cancers. To evaluate the antitumor effects of CB-LHRH’, three drug resistant ovarian cancer cell lines (SKOV-3, ES-2, NIH:OVCAR-3) and an endometrial cancer cell line (HEC-1A) were treated with CB-LHRH’. Cell morphology changes were assessed using inverted and electron microscopes. In addition, cell growth and cell cytotoxicity were measured by MTT assay and LDH release, respectively. In addition, hemolysis was measured. Furthermore, radioligand receptor binding, hypersensitization and minimal inhibitory concentrations (against Staphylococcus aureus, Klebsiella pneumoniae, Escherichia coli, Enterobacter cloacae, Pseudomonas aeruginosa, and Acinetobacter baumannii) were determined. Finally, the impact on tumor growth in BALB/c-nu mice was assessed in an ES-2 xenograft model. CB-LHRH’ bound LHRHr with high-affinity (dissociation constant, Kd = 0.252 ± 0.061nM). Interestingly, CB-LHRH’ significantly inhibited the cell viability of SKOV-3, ES-2, NIH:OVCAR-3 and HEC-1A, but not that of normal eukaryotic cells. CB-LHRH’ was active against bacteria at micromolar concentrations, and caused no hypersensitivity in guinea pigs. Furthermore, CB-LHRH’ inhibited tumor growth with a 23.8 and 20.4 % reduction in tumor weight at 50 and 25 mg/kg.d, respectively. CB-LHRH’ is a candidate for targeted chemotherapy against ovarian and endometrial cancers

  6. RhoB mediates antitumor synergy of combined ixabepilone and sunitinib in human ovarian serous cancer.

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    Vishnu, Prakash; Colon-Otero, Gerardo; Kennedy, Gregory T; Marlow, Laura A; Kennedy, William P; Wu, Kevin J; Santoso, Joseph T; Copland, John A

    2012-03-01

    The aim was to evaluate antitumor activity of the combination of ixabepilone and sunitinib in pre-clinical models of chemotherapy naïve and refractory epithelial ovarian tumors, and to investigate the mechanism of synergy of such drug combination. HOVTAX2 cell line was derived from a metastatic serous papillary epithelial ovarian tumor (EOC) and a paclitaxel-resistant derivative was established. Dose response curves for ixabepilone and sunitinib were generated and synergy was determined using combination indexes. The molecular mechanism of antitumor synergy was examined using shRNA silencing. The combination of ixabepilone and sunitinib demonstrated robust antitumor synergy in naïve and paclitaxel-resistant HOVTAX2 cell lines due to increased apoptosis. The GTPase, RhoB, was synergistically upregulated in cells treated with ixabepilone and sunitinib. Using shRNA, RhoB was demonstrated to mediate antitumor synergy. These results were validated in two other EOC cell lines. Ixabepilone plus sunitinib demonstrated antitumor synergy via RhoB in naïve and paclitaxel-resistant cells resulting in apoptosis. This study demonstrates a novel mechanism of action leading to antitumor synergy and provides 'proof-of-principle' for combining molecular targeted agents with cytotoxic chemotherapy to improve antitumor efficacy. RhoB could be envisioned as an early biomarker of response to therapy in a planned Phase II clinical trial to assess the efficacy of ixabepilone combined with a receptor tyrosine kinase inhibitor such as sunitinib. To the best of our knowledge, this is the first demonstration of antitumor synergy between these two classes of drugs in EOC and the pivotal role of RhoB in this synergy. Copyright © 2011 Elsevier Inc. All rights reserved.

  7. Antitumor Responses of Invariant Natural Killer T Cells

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    Jennie B. Altman

    2015-01-01

    Full Text Available Natural killer T (NKT cells are innate-like lymphocytes that were first described in the late 1980s. Since their initial description, numerous studies have collectively shed light on their development and effector function. These studies have highlighted the unique requirements for the activation of these lymphocytes and the functional responses that distinguish these cells from other effector lymphocyte populations such as conventional T cells and NK cells. This body of literature suggests that NKT cells play diverse nonredundant roles in a number of disease processes, including the initiation and propagation of airway hyperreactivity, protection against a variety of pathogens, development of autoimmunity, and mediation of allograft responses. In this review, however, we focus on the role of a specific lineage of NKT cells in antitumor immunity. Specifically, we describe the development of invariant NKT (iNKT cells and the factors that are critical for their acquisition of effector function. Next, we delineate the mechanisms by which iNKT cells influence and modulate the activity of other immune cells to directly or indirectly affect tumor growth. Finally, we review the successes and failures of clinical trials employing iNKT cell-based immunotherapies and explore the future prospects for the use of such strategies.

  8. Cigarette smoke alters the invariant natural killer T cell function and may inhibit anti-tumor responses.

    LENUS (Irish Health Repository)

    Hogan, Andrew E

    2011-09-01

    Invariant natural killer T (iNKT) cells are a minor subset of human T cells which express the invariant T cell receptor Vα24 Jα18 and recognize glycolipids presented on CD1d. Invariant NKT cells are important immune regulators and can initiate anti-tumor responses through early potent cytokine production. Studies show that iNKT cells are defective in certain cancers. Cigarette smoke contains many carcinogens and is implicated directly and indirectly in many cancers. We investigated the effects of cigarette smoke on the circulating iNKT cell number and function. We found that the iNKT cell frequency is significantly reduced in cigarette smoking subjects. Invariant NKT cells exposed to cigarette smoke extract (CSE) showed significant defects in cytokine production and the ability to kill target cells. CSE inhibits the upregulation of CD107 but not CD69 or CD56 on iNKT cells. These findings suggest that CSE has a specific effect on iNKT cell anti-tumor responses, which may contribute to the role of smoking in the development of cancer.

  9. Potentiation of antitumor immunity in tumor-bearing mice by a degraded D-manno-D-glucan (DMG), a new antitumor polysaccharide.

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    Nakajima, H; Kita, Y; Hashimoto, S; Tsukada, W; Abe, S; Mizuno, D

    1983-12-01

    DMG, a degraded D-manno-D-glucan from the culture fluid of Microellobosporia grisea, inhibited the growth of murine syngeneic MM46 mammary carcinoma. Mice in which the tumor had completely regressed by DMG treatment showed tumor-specific antitumor resistance. The antitumor action of DMG was studied by examining the influences of DMG on tumor-specific and non-specific immune responses in tumor-bearing hosts. The tumor-specific delayed hypersensitivity reaction appeared transiently on day 7 after tumor inoculation but had decreased by day 15 in untreated tumor-bearing mice. In contrast, the reaction was retained and augmented in DMG-treated tumor-bearing mice. The tumor-neutralizing activity of spleen cells from DMG-treated tumor-bearing mice, tested by a Winn assay, was tumor-specific and significantly higher than that of untreated tumor-bearing mice. The tumor-neutralizing activity of peritoneal cells and the in vitro cytostatic activity of peritoneal macrophages in response to lymphokine supernatants containing macrophage activation factor were also augmented by DMG treatment. In contrast, the level of antitumor antibody in the serum increased with time, irrespective of DMG administration. Thus, DMG potentiated cellular antitumor effector mechanisms.

  10. Hypoxia-targeting antitumor prodrugs and photosensitizers

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    Zhang Zhouen; Nishimoto, S.I.

    2006-01-01

    Tumor hypoxia has been identified as a key subject for tumor therapy, since hypoxic tumor cells show resistance to treatment of tumor tissues by radiotherapy, chemotherapy and phototherapy. For improvement of tumor radiotherapy, we have proposed a series of radiation-activated prodrugs that could selectively release antitumor agent 5-fluorouracil or 5-fluorodeoxyuridine under hypoxic conditions. Recently, we attempted to develop two families of novel hypoxia-targeting antitumor agents, considering that tumor-hypoxic environment is favorable to biological and photochemical reductions. The first family of prodrugs was derived from camptothecin as a potent topoisomerase I inhibitor and several bioreductive motifs. These prodrugs could be activated by NADPH-cytochrome P450 reductase or DT-diaphorase to release free camptothecin, and thereby showed hypoxia-selective cytotoxictiy towards tumor cells. These prodrugs were also applicable to the real-time monitoring of activation and antitumor effect by fluorometry. Furthermore, the camptothecin-bioreductive motif conjugates was confirmed to show an oxygen-independent DAN photocleaving activity, which could overcome a drawback of back electron transfer occurring in the photosensitized one-electron oxidation of DNA. Thus, these camptothecin derivatives could be useful to both chemotherapy and phototherapy for hypoxic tumor cells. The second family of prodrugs harnessed UV light for cancer therapy, incorporating the antitumor agent 5-fluorourcil and the photolabile 2-nitrobenzyl chromophores. The attachment of a tumor-homing cyclic peptide CNGRC was also employed to construct the prototype of tumor-targeting photoactiaved antitumor prodrug. These novel prodrugs released high yield of 5-fluorourcil upon UV irradiation at λ ex =365 nm, while being quite stable in the dark. The photoactivation mechanism was also clarified by means of nanosecond laser flash photolysis. (authors)

  11. The antitumor natural product tanshinone IIA inhibits protein kinase C and acts synergistically with 17-AAG.

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    Lv, Chao; Zeng, Hua-Wu; Wang, Jin-Xin; Yuan, Xing; Zhang, Chuang; Fang, Ting; Yang, Pei-Ming; Wu, Tong; Zhou, Yu-Dong; Nagle, Dale G; Zhang, Wei-Dong

    2018-02-07

    Tanshinone IIA (Tan IIA), the primary bioactive compound derived from the traditional Chinese medicine (TCM) Salvia miltiorrhiza Bunge, has been reported to possess antitumor activity. However, its antitumor mechanisms are not fully understood. To resolve the potential antitumor mechanism(s) of Tan IIA, its gene expression profiles from our database was analyzed by connectivity map (CMAP) and the CMAP-based mechanistic predictions were confirmed/validated in further studies. Specifically, Tan IIA inhibited total protein kinase C (PKC) activity and selectively suppressed the expression of cytosolic and plasma membrane PKC isoforms ζ and ε. The Ras/MAPK pathway that is closely regulated by the PKC signaling is also inhibited by Tan IIA. While Tan IIA did not inhibit heat shock protein 90 (Hsp90), it synergistically enhanced the antitumor efficacy of the Hsp90 inhibitors 17-AAG and ganetespib in human breast cancer MCF-7 cells. In addition, Tan IIA significantly inhibited PI3K/Akt/mTOR signaling, and induced both cell cycle arrest and autophagy. Collectively, these studies provide new insights into the molecular mechanisms responsible for antitumor activity of Tan IIA.

  12. Antitumor Activities of Kushen: Literature Review

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    Mingyu Sun

    2012-01-01

    Full Text Available To discover and develop novel natural compounds with therapeutic selectivity or that can preferentially kill cancer cells without significant toxicity to normal cells is an important area in cancer chemotherapy. Kushen, the dried roots of Sophora flavescens Aiton, has a long history of use in traditional Chinese medicine to treat inflammatory diseases and cancer. Kushen alkaloids (KS-As and kushen flavonoids (KS-Fs are well-characterized components in kushen. KS-As containing oxymatrine, matrine, and total alkaloids have been developed in China as anticancer drugs. More potent antitumor activities were identified in KS-Fs than in KS-As in vitro and in vivo. KS-Fs may be developed as novel antitumor agents.

  13. Reprogramming antitumor immunity against chemoresistant ovarian cancer by a CXCR4 antagonist-armed viral oncotherapy

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    Marcin P Komorowski

    2016-01-01

    Full Text Available Ovarian cancer remains the most lethal gynecologic malignancy owing to late detection, intrinsic and acquired chemoresistance, and remarkable heterogeneity. Here, we explored approaches to inhibit metastatic growth of murine and human ovarian tumor variants resistant to paclitaxel and carboplatin by oncolytic vaccinia virus expressing a CXCR4 antagonist to target the CXCL12 chemokine/CXCR4 receptor signaling axis alone or in combination with doxorubicin. The resistant variants exhibited augmented expression of the hyaluronan receptor CD44 and CXCR4 along with elevated Akt and ERK1/2 activation and displayed an increased susceptibility to viral infection compared with the parental counterparts. The infected cultures were more sensitive to doxorubicin-mediated killing both in vitro and in tumor-challenged mice. Mechanistically, the combination treatment increased apoptosis and phagocytosis of tumor material by dendritic cells associated with induction of antitumor immunity. Targeting syngeneic tumors with this regimen increased intratumoral infiltration of antitumor CD8+ T cells. This was further enhanced by reducing the immunosuppressive network by the virally-delivered CXCR4 antagonist, which augmented antitumor immune responses and led to tumor-free survival. Our results define novel strategies for treatment of drug-resistant ovarian cancer that increase immunogenic cell death and reverse the immunosuppressive tumor microenvironment, culminating in antitumor immune responses that control metastatic tumor growth.

  14. Natural disease resistance in threatened staghorn corals.

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    Steven V Vollmer

    Full Text Available Disease epidemics have caused extensive damage to tropical coral reefs and to the reef-building corals themselves, yet nothing is known about the abilities of the coral host to resist disease infection. Understanding the potential for natural disease resistance in corals is critically important, especially in the Caribbean where the two ecologically dominant shallow-water corals, Acropora cervicornis and A. palmata, have suffered an unprecedented mass die-off due to White Band Disease (WBD, and are now listed as threatened under the US Threatened Species Act and as critically endangered under the IUCN Red List criteria. Here we examine the potential for natural resistance to WBD in the staghorn coral Acropora cervicornis by combining microsatellite genotype information with in situ transmission assays and field monitoring of WBD on tagged genotypes. We show that six percent of staghorn coral genotypes (3 out of 49 are resistant to WBD. This natural resistance to WBD in staghorn corals represents the first evidence of host disease resistance in scleractinian corals and demonstrates that staghorn corals have an innate ability to resist WBD infection. These resistant staghorn coral genotypes may explain why pockets of Acropora have been able to survive the WBD epidemic. Understanding disease resistance in these corals may be the critical link to restoring populations of these once dominant corals throughout their range.

  15. Naturally occurring immunomodulators with antitumor activity: An insight on their mechanisms of action.

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    Mohamed, Shimaa Ibrahim Abdelmonym; Jantan, Ibrahim; Haque, Md Areeful

    2017-09-01

    Natural products with immunomodulatory activity are widely used in treatment of many diseases including autoimmune diseases, inflammatory disorders in addition to cancer. They gained a great interest in the last decades as therapeutic agents since they provide inexpensive and less toxic products than the synthetic chemotherapeutic agents. Immunomodulators are the agents that have the ability to boost or suppress the host defense response that can be used as a prophylaxis as well as in combination with other therapeutic modalities. The anticancer activity of these immunomodulators is due to their anti-inflammatory, antioxidant, and induction of apoptosis, anti-angiogenesis, and anti-metastasis effect. These natural immunomodulators such as genistein, curcumin, and resveratrol can be used as prophylaxis against the initiation of cancer besides the inhibition of tumor growth and proliferation. Whereas, immunostimulants can elicit and activate humoral and cell-mediated immune responses against the tumor that facilitate the recognition and destruction of the already existing tumor. This review represents the recent studies on various natural immunomodulators with antitumor effects. We have focused on the relationship between their anticancer activity and immunomodulatory mechanisms. The mechanisms of action of various immunomodulators such as polyphenolic compounds, flavonoids, organosulfur compounds, capsaicin, vinca alkaloids, bromelain, betulinic acid and zerumbone, the affected cancerous cell lines in addition to the targeted molecules and transcriptional pathways have been review and critically analyzed. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Predation and selection for antibiotic resistance in natural environments

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    Leisner, Jørgen; Jørgensen, Niels O. G.; Middelboe, Mathias

    2016-01-01

    Genes encoding resistance to antibiotics appear, like the antibiotics themselves, to be ancient, originating long before the rise of the era of anthropogenic antibiotics. However, detailed understanding of the specific biological advantages of antibiotic resistance in natural environments is still...... lacking, thus limiting our efforts to prevent environmental influx of resistance genes. Here, we propose that antibiotic-resistant cells not only evade predation from antibiotic producers but also take advantage of nutrients released from cells that are killed by the antibiotic-producing bacteria. Thus......, predation is potentially an important mechanism for driving antibiotic resistance during slow or stationary phase of growth when nutrients are deprived. This adds to explain the ancient nature and widespread occurrence of antibiotic resistance in natural environments unaffected by anthropogenic antibiotics...

  17. Resistance to minor groove binders.

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    Colmegna, Benedetta; Uboldi, Sarah; Erba, Eugenio; D'Incalci, Maurizio

    2014-03-01

    In this paper multiple resistance mechanisms to minor groove binders (MGBs) are overviewed. MGBs with antitumor properties are natural products or their derivatives and, as expected, they are all substrates of P-glycoprotein (P-gp). However, a moderate expression of P-gp does not appear to reduce the sensitivity to trabectedin, the only MGB so far approved for clinical use. Resistance to this drug is often related to transcriptional mechanisms and to DNA repair pathways, particularly defects in transcription-coupled nucleotide excision repair (TC-NER). Therefore tumors resistant to trabectedin may become hypersensitive to UV rays and other DNA damaging agents acting in the major groove, such as Platinum (Pt) complexes. If this is confirmed in clinic, that will provide the rationale to combine trabectedin sequentially with Pt derivates.

  18. Ectopic expression of X-linked lymphocyte-regulated protein pM1 renders tumor cells resistant to antitumor immunity.

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    Kang, Tae Heung; Noh, Kyung Hee; Kim, Jin Hee; Bae, Hyun Cheol; Lin, Ken Y; Monie, Archana; Pai, Sara I; Hung, Chien-Fu; Wu, T-C; Kim, Tae Woo

    2010-04-15

    Tumor immune escape is a major obstacle in cancer immunotherapy, but the mechanisms involved remain poorly understood. We have previously developed an immune evasion tumor model using an in vivo immune selection strategy and revealed Akt-mediated immune resistance to antitumor immunity induced by various cancer immunotherapeutic agents. In the current study, we used microarray gene analysis to identify an Akt-activating candidate molecule overexpressed in immune-resistant tumors compared with parental tumors. X-linked lymphocyte-regulated protein pM1 (XLR) gene was the most upregulated in immune-resistant tumors compared with parental tumor cells. Furthermore, the retroviral transduction of XLR in parental tumor cells led to activation of Akt, resulting in upregulation of antiapoptotic proteins and the induction of immune resistance phenotype in parental tumor cells. In addition, we found that transduction of parental tumor cells with other homologous genes from the mouse XLR family, such as synaptonemal complex protein 3 (SCP3) and XLR-related, meiosis-regulated protein (XMR) and its human counterpart of SCP3 (hSCP3), also led to activation of Akt, resulting in the upregulation of antiapoptotic proteins and induction of immune resistance phenotype. Importantly, characterization of a panel of human cervical cancers revealed relatively higher expression levels of hSCP3 in human cervical cancer tissue compared with normal cervical tissue. Thus, our data indicate that ectopic expression of XLR and its homologues in tumor cells represents a potentially important mechanism for tumor immune evasion and serves as a promising molecular target for cancer immunotherapy. (c) 2010 AACR.

  19. Antitumor and Antimicrobial Activity of Some Cyclic Tetrapeptides and Tripeptides Derived from Marine Bacteria

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    Subrata Chakraborty

    2015-05-01

    Full Text Available Marine derived cyclo(Gly-l-Ser-l-Pro-l-Glu was selected as a lead to evaluate antitumor-antibiotic activity. Histidine was chosen to replace the serine residue to form cyclo(Gly-l-His-l-Pro-l-Glu. Cyclic tetrapeptides (CtetPs were then synthesized using a solution phase method, and subjected to antitumor and antibiotic assays. The benzyl group protected CtetPs derivatives, showed better activity against antibiotic-resistant Staphylococcus aureus in the range of 60–120 μM. Benzyl group protected CtetPs 3 and 4, exhibited antitumor activity against several cell lines at a concentration of 80–108 μM. However, shortening the size of the ring to the cyclic tripeptide (CtriP scaffold, cyclo(Gly-l-Ser-l-Pro, cyclo(Ser-l-Pro-l-Glu and their analogues showed no antibiotic or antitumor activity. This phenomenon can be explained from their backbone structures.

  20. Inhibition of eukaryotic translation elongation by the antitumor natural product Mycalamide B.

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    Dang, Yongjun; Schneider-Poetsch, Tilman; Eyler, Daniel E; Jewett, John C; Bhat, Shridhar; Rawal, Viresh H; Green, Rachel; Liu, Jun O

    2011-08-01

    Mycalamide B (MycB) is a marine sponge-derived natural product with potent antitumor activity. Although it has been shown to inhibit protein synthesis, the molecular mechanism of action by MycB remains incompletely understood. We verified the inhibition of translation elongation by in vitro HCV IRES dual luciferase assays, ribosome assembly, and in vivo [(35)S]methinione labeling experiments. Similar to cycloheximide (CHX), MycB inhibits translation elongation through blockade of eEF2-mediated translocation without affecting the eEF1A-mediated loading of tRNA onto the ribosome, AUG recognition, or dipeptide synthesis. Using chemical footprinting, we identified the MycB binding site proximal to the C3993 28S rRNA residue on the large ribosomal subunit. However, there are also subtle, but significant differences in the detailed mechanisms of action of MycB and CHX. First, MycB arrests the ribosome on the mRNA one codon ahead of CHX. Second, MycB specifically blocked tRNA binding to the E-site of the large ribosomal subunit. Moreover, they display different polysome profiles in vivo. Together, these observations shed new light on the mechanism of inhibition of translation elongation by MycB.

  1. Molecular mechanisms of bortezomib resistant adenocarcinoma cells.

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    Erika Suzuki

    Full Text Available Bortezomib (Velcade™ is a reversible proteasome inhibitor that is approved for the treatment of multiple myeloma (MM. Despite its demonstrated clinical success, some patients are deprived of treatment due to primary refractoriness or development of resistance during therapy. To investigate the role of the duration of proteasome inhibition in the anti-tumor response of bortezomib, we established clonal isolates of HT-29 adenocarcinoma cells adapted to continuous exposure of bortezomib. These cells were ~30-fold resistant to bortezomib. Two novel and distinct mutations in the β5 subunit, Cys63Phe, located distal to the binding site in a helix critical for drug binding, and Arg24Cys, found in the propeptide region were found in all resistant clones. The latter mutation is a natural variant found to be elevated in frequency in patients with MM. Proteasome activity and levels of both the constitutive and immunoproteasome were increased in resistant cells, which correlated to an increase in subunit gene expression. These changes correlated with a more rapid recovery of proteasome activity following brief exposure to bortezomib. Increased recovery rate was not due to increased proteasome turnover as similar findings were seen in cells co-treated with cycloheximide. When we exposed resistant cells to the irreversible proteasome inhibitor carfilzomib we noted a slower rate of recovery of proteasome activity as compared to bortezomib in both parental and resistant cells. Importantly, carfilzomib maintained its cytotoxic potential in the bortezomib resistant cell lines. Therefore, resistance to bortezomib, can be overcome with irreversible inhibitors, suggesting prolonged proteasome inhibition induces a more potent anti-tumor response.

  2. Comparative study of the antitumor effect of natural monoterpenes: relationship to cell cycle analysis

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    Abdeslam Jaafari

    2012-06-01

    Full Text Available Monoterpenes have been identified as responsible of important therapeutic effects of plant-extracts. In this work, we try to compare the cytotoxic effect of six monoterpenes (carvacrol, thymol, carveol, carvone, eugenol and isopulegol as well as their molecular mechanisms. The in vitro antitumor activity of the tested products, evaluated against five tumor cell lines, show that the carvacrol is the most cytotoxic monoterpene. The investigation of an eventual synergistic effect of the six natural monoterpenes with two anticancer drugs revealed that there is a significant synergy between them (p<5%. On the other hand, the effect of the tested products on cell cycle progression was examined by flow cytometry after DNA staining in order to investigate the molecular mechanism of their cytotoxic activity. The results revealed that carvacrol and carveol stopped the cell cycle progression in S phase; however, thymol and isopulegol stopped it in G0/G1 phase. Regarding carvone and eugenol, no effect on cell cycle was observed.

  3. Nonlocal nature of the resistance in classical ballistic transport

    International Nuclear Information System (INIS)

    Sukhorukov, E.V.; Levinson, I.B.

    1990-01-01

    An investigation is made of the resistance of ballistic microstructures formed in the two-dimensional electron gas of a GaAs/AlGaAs heterojunction representing combinations of long channels. It is shown that the nonlocal nature of the resistance (dependence on the measurement method) is unrelated to the quantum nature of the electron behavior, but is solely due to the ballistic nature of microstructures and does not disappear in the classical limit. An analog of the Landauer equation is obtained for the resistance measured by the four-probe method allowing for the geometry of the measuring probes

  4. Antibacterial, antioxidant and antitumor properties of Moroccan medicinal plants: A review

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    Abdelhakim Bouyahya

    2017-01-01

    Full Text Available Aromatic and medicinal plants have been traditionally used since antiquity to fight against illnesses. Recently, several researches have focused on the pharmacological properties and various bioactivities of natural products are extracted from medicinal plants, including the properties of antibacterial, antitumor and antioxidant activities. The products of medicinal plants are the secondary metabolites belonging to different compound classes such as essential oils, polyphenols, flavonoids and other phytochemical classes. In Morocco, medicinal plants are the major source of bioactive compounds and the majority of them are used in phytotherapy. The biological potential of various Moroccan medicinal plants attracts a lot of interest in the literature. They include antibacterial, antioxidant and antitumor investigations. In this context, this work aims at discussing antibacterial, antitumor and antioxidant properties of Moroccan medicinal plants.

  5. Oral Metronomic Topotecan Sensitizes Crizotinib Antitumor Activity in ALKF1174L Drug-Resistant Neuroblastoma Preclinical Models

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    Libo Zhang

    2017-08-01

    Full Text Available BACKGROUND: Anaplastic lymphoma kinase (ALK inhibitor crizotinib has proven to be effective in the treatment of ALK-mutated neuroblastoma, but crizotinib resistance was commonly observed in patients. We aimed to overcome crizotinib resistance by combining with the MEK inhibitor trametinib or low-dose metronomic (LDM topotecan in preclinical neuroblastoma models. METHODS: We selected a panel of neuroblastoma cell lines carrying various ALK genetic aberrations to assess the therapeutic efficacy on cell proliferation in vitro. Downstream signals of ALK activation, including phosphorylation of ERK1/2, Akt as well as HIF-1α expression were evaluated under normoxic and hypoxic conditions. Tumor growth inhibition was further assessed in NOD/SCID xenograft mouse models. RESULTS: All NBL cell lines responded to crizotinib treatment but at variable ED50 levels, ranging from 0.25 to 5.58 μM. ALK-mutated cell lines SH-SY5Y, KELLY, LAN-5, and CHLA-20 are more sensitive than ALK wild-type cell lines. In addition, we demonstrated that under hypoxic conditions, all NBL cell lines showed marked decrease of ED50s when compared to normoxia except for KELLY cells. Taking into consideration the hypoxia sensitivity to crizotinib, combined treatment with crizotinib and LDM topotecan demonstrated a synergistic effect in ALKF1174L-mutated SH-SY5Y cells. In vivo, single-agent crizotinib showed limited antitumor activity in ALKF1174L-mutated SH-SY5Y and KELLY xenograft models; however, when combined with topotecan, significantly delayed tumor development was achieved in both SH-SY5Y and KELLY tumor models. CONCLUSIONS: Oral metronomic topotecan reversed crizotinib drug resistance in the ALKF1174L-mutated neuroblastoma preclinical model.

  6. The multifaceted roles of antibiotics and antibiotic resistance in nature

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    Saswati eSengupta

    2013-03-01

    Full Text Available Antibiotics are chemotherapeutic agents, which have been a very powerful tool in the clinical management of bacterial diseases since the 1940s. However, benefits offered by these magic bullets have been substantially lost in subsequent days following the widespread emergence and dissemination of antibiotic resistant strains. While it is obvious that excessive and imprudent use of antibiotics significantly contributes to the emergence of resistant strains, antibiotic-resistance is also observed in natural bacteria of remote places unlikely to be impacted by human intervention. Both antibiotic biosynthetic genes and resistance-conferring genes have been known to evolve billions of years ago, long before clinical use of antibiotics. Hence it appears that antibiotics and antibiotics resistance determinants have some other roles in nature, which often elude our attention because of overemphasis on the therapeutic importance of antibiotics and the crisis imposed by the antibiotic-resistance in pathogens. In the natural milieu, antibiotics are often found to be present in subinhibitory concentrations acting as signalling molecules supporting quorum sensing and biofilm formation. They also play an important role in the production of virulence factors and influence host-parasite interactions (e.g., phagocytosis, adherence to the target cell and so on. The evolutionary and ecological aspects of antibiotics and antibiotic-resistance in the naturally occurring microbial community are little understood. Therefore, the actual role of antibiotics in nature warrants in-depth investigations. Studies on such an intriguing behaviour of the microorganisms promise insight into the intricacies of the microbial physiology and are likely to provide some lead in controlling the emergence and subsequent dissemination of antibiotic resistance. This article highlights some of the recent findings on the role of antibiotics and genes that confer resistance to antibiotics in

  7. Amplexicaule A exerts anti-tumor effects by inducing apoptosis in human breast cancer

    Science.gov (United States)

    Shu, Guangwen; Wan, Dingrong; He, Feng; Loaec, Morgann; Ding, Yali; Li, Jun; Dovat, Sinisa; Yang, Gaungzhong; Song, Chunhua

    2016-01-01

    Chemotherapy is the main treatment for patients with breast cancer metastases, but natural alternatives have been receiving attention for their potential as novel anti-tumor reagents. Amplexicaule A (APA) is a flavonoid glucoside isolated from rhizomes of Polygonum amplexicaule D. Don var. sinense Forb (PADF). We found that APA has anti-tumor effects in a breast cancer xenograft mouse model and induces apoptosis in breast cancer cell lines. APA increased levels of cleaved caspase-3,-8,-9 and PARP, which resulted from suppression of MCL-1 and BCL-2 expression in the cells. APA also inactivated the Akt/mTOR pathway in breast cancer cells. Thus, APA exerts a strong anti-tumor effect on breast cancer cells, most likely through induction of apoptosis. Our study is the first to identify this novel anti-tumor compound and provides a new strategy for isolation and separation of single compounds from herbs. PMID:26943775

  8. Antitumor efficacy of triple monoclonal antibody inhibition of epidermal growth factor receptor (EGFR) with MM151 in EGFR-dependent and in cetuximab-resistant human colorectal cancer cells

    Science.gov (United States)

    Napolitano, Stefania; Martini, Giulia; Martinelli, Erika; Della Corte, Carminia Maria; Morgillo, Floriana; Belli, Valentina; Cardone, Claudia; Matrone, Nunzia; Ciardiello, Fortunato; Troiani, Teresa

    2017-01-01

    Purpose We investigated the effect of triple monoclonal antibody inhibition of EGFR to overcome acquired resistance to first generation of anti-EGFR inhibitors. Experimental design MM151 is a mixture of three different monoclonal IgG1 antibodies directed toward three different, non-overlapping, epitopes of the EGFR. We performed an in vivo study by using human CRC cell lines (SW48, LIM 1215 and CACO2) which are sensitive to EGFR inhibitors, in order to evaluate the activity of MM151 as compared to standard anti-EGFR mAbs, such as cetuximab, as single agent or in a sequential strategy of combination MM151 with irinotecan (induction therapy) followed by MM151 with a selective MEK1/2 inhibitor (MEKi) (maintenance therapy). Furthermore, the ability of MM151 to overcome acquired resistance to cetuximab has been also evaluated in cetuximab-refractory CRC models. Results MM151 shown stronger antitumor activity as compared to cetuximab. The maintenance treatment with MM151 plus MEKi resulted the most effective therapeutic modality. In fact, this combination caused an almost complete suppression of tumor growth in SW48, LIM 1215 and CACO2 xenografts model at 30 week. Moreover, in this treatment group, mice with no evidence of tumor were more than double as compared to single agent treated mice. Its superior activity has also been demonstrated, in cetuximab-refractory CRC models. Conclusions These results provide experimental evidence that more efficient and complete EGFR blockade may determine better antitumor activity and could contribute to prevent and/or overcome acquired resistance to EGFR inhibitors. PMID:29137301

  9. Amplexicaule A exerts anti-tumor effects by inducing apoptosis in human breast cancer

    OpenAIRE

    Xiang, Meixian; Su, Hanwen; Shu, Guangwen; Wan, Dingrong; He, Feng; Loaec, Morgann; Ding, Yali; Li, Jun; Dovat, Sinisa; Yang, Gaungzhong; Song, Chunhua

    2016-01-01

    Chemotherapy is the main treatment for patients with breast cancer metastases, but natural alternatives have been receiving attention for their potential as novel anti-tumor reagents. Amplexicaule A (APA) is a flavonoid glucoside isolated from rhizomes of Polygonum amplexicaule D. Don var. sinense Forb (PADF). We found that APA has anti-tumor effects in a breast cancer xenograft mouse model and induces apoptosis in breast cancer cell lines. APA increased levels of cleaved caspase-3,-8,-9 and ...

  10. Antitumoral activity of marine organism; Actividad antitumoral de los organismos marinos

    Energy Technology Data Exchange (ETDEWEB)

    Valdes Iglesias, O [Centro de Bioproductos Marinos, La Habana (Cuba); Perez Gil, R; Colom, Y [Instituno Nacional de Oncologia y Radiobiologia (INOR), La Habana (Cuba)

    2010-07-01

    The study of the natural products from marine organism constitute a relatively recent scientific researcher field with high potentialities tanking in consideration that the oceans cover the three of the four parts of the earth. Poryphera and Bryozoans have been the Phylum more studied owning to the vulnerability, their soft body, their habitat on rocks, their slow movement and bright colors, for these reason these organisms are able to produce chemical substances as defense methods against depredators. Same mechanism is exhibit by the seaweeds with the production of secondary metabolites . In the present communication are exposed the main results obtained on the world a Cuba until the present in the looking for of substances with antitumor action from marine organism.

  11. Antioxidant Intake and Antitumor Therapy: Toward Nutritional Recommendations for Optimal Results

    Science.gov (United States)

    Mut-Salud, Nuria; Álvarez, Pablo Juan; Garrido, Jose Manuel; Carrasco, Esther; Aránega, Antonia; Rodríguez-Serrano, Fernando

    2016-01-01

    The role of the induction of oxidative stress as the mechanism of action of many antitumor drugs is acquiring an increasing interest. In such cases, the antitumor therapy success may be conditioned by the antioxidants present in our own body, which can be synthesized de novo (endogenous) or incorporated through the diet and nutritional supplements (exogenous). In this paper, we have reviewed different aspects of antioxidants, including their classification, natural sources, importance in diet, consumption of nutritional supplements, and the impact of antioxidants on health. Moreover, we have focused especially on the study of the interaction between antioxidants and antitumor therapy, considering both radiotherapy and chemotherapy. In this regard, we found that the convenience of administration of antioxidants during cancer treatment still remains a very controversial issue. In general terms, antioxidants could promote or suppress the effectiveness of antitumor treatment and even protect healthy tissues against damage induced by oxidative stress. The effects may depend on many factors discussed in the paper. These factors should be taken into consideration in order to achieve precise nutritional recommendations for patients. The evidence at the moment suggests that the supplementation or restriction of exogenous antioxidants during cancer treatment, as appropriate, could contribute to improving its efficiency. PMID:26682013

  12. Antioxidant Intake and Antitumor Therapy: Toward Nutritional Recommendations for Optimal Results

    Directory of Open Access Journals (Sweden)

    Nuria Mut-Salud

    2016-01-01

    Full Text Available The role of the induction of oxidative stress as the mechanism of action of many antitumor drugs is acquiring an increasing interest. In such cases, the antitumor therapy success may be conditioned by the antioxidants present in our own body, which can be synthesized de novo (endogenous or incorporated through the diet and nutritional supplements (exogenous. In this paper, we have reviewed different aspects of antioxidants, including their classification, natural sources, importance in diet, consumption of nutritional supplements, and the impact of antioxidants on health. Moreover, we have focused especially on the study of the interaction between antioxidants and antitumor therapy, considering both radiotherapy and chemotherapy. In this regard, we found that the convenience of administration of antioxidants during cancer treatment still remains a very controversial issue. In general terms, antioxidants could promote or suppress the effectiveness of antitumor treatment and even protect healthy tissues against damage induced by oxidative stress. The effects may depend on many factors discussed in the paper. These factors should be taken into consideration in order to achieve precise nutritional recommendations for patients. The evidence at the moment suggests that the supplementation or restriction of exogenous antioxidants during cancer treatment, as appropriate, could contribute to improving its efficiency.

  13. Medicinal Plants and Other Living Organisms with Antitumor Potential against Lung Cancer

    Directory of Open Access Journals (Sweden)

    Luara de Sousa Monteiro

    2014-01-01

    Full Text Available Lung cancer is a disease with high morbidity and mortality rates. As a result, it is often associated with a significant amount of suffering and a general decrease in the quality of life. Herbal medicines are recognized as an attractive approach to lung cancer therapy with little side effects and are a major source of new drugs. The aim of this work was to review the medicinal plants and other living organisms with antitumor potential against lung cancer. The assays were conducted with animals and humans, and Lewis lung carcinoma was the most used experimental model. China, Japan, South Korea, and Ethiopia were the countries that most published studies of species with antitumor activity. Of the 38 plants evaluated, 27 demonstrated antitumor activity. In addition, six other living organisms were cited for antitumor activity against lung cancer. Mechanisms of action, combination with chemotherapeutic drugs, and new technologies to increase activity and reduce the toxicity of the treatment are discussed. This review was based on the NAPRALERT databank, Web of Science, and Chemical Abstracts. This work shows that natural products from plants continue to be a rich source of herbal medicines or biologically active compounds against cancer.

  14. Chemically crosslinked nanogels of PEGylated poly ethyleneimine (L-histidine substituted) synthesized via metal ion coordinated self-assembly for delivery of methotrexate: Cytocompatibility, cellular delivery and antitumor activity in resistant cells

    Energy Technology Data Exchange (ETDEWEB)

    Abolmaali, Samira Sadat, E-mail: s.abolmaali@gmail.com [Pharmaceutical Nanotechnology Department, Shiraz University of Medical Sciences, Shiraz 71345 (Iran, Islamic Republic of); Tamaddon, Ali Mohammad, E-mail: amtamadon@gmail.com [Center for Nanotechnology in Drug Delivery, Shiraz University of Medical Sciences, Shiraz 71345 (Iran, Islamic Republic of); Mohammadi, Samaneh, E-mail: samaneh.mohammadi1986@gmail.com [Center for Nanotechnology in Drug Delivery, Shiraz University of Medical Sciences, Shiraz 71345 (Iran, Islamic Republic of); Amoozgar, Zohreh, E-mail: zohreh_amoozgar@dfci.harvard.edu [Department of Cancer Immunology and Aids, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA 02115 (United States); Dinarvand, Rasoul, E-mail: dinarvand@tums.ac.ir [Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran 14174 (Iran, Islamic Republic of)

    2016-05-01

    Self-assembled nanogels were engineered by forming Zn{sup 2+}-coordinated micellar templates of PEGylated poly ethyleneimine (PEG-g-PEI), chemical crosslinking and subsequent removal of the metal ion. Creation of stable micellar templates is a crucial step for preparing the nanogels. To this aim, imidazole moieties were introduced to the polymer by Fmoc-L-histidine using carbodiimide chemistry. It was hypothesized the nanogels loaded with methotrexate (MTX), a chemotherapeutic agent, circumvent impaired carrier activity in HepG2 cells (MTX-resistant hepatocellular carcinoma). So, the nanogels were post-loaded with MTX and characterized by {sup 1}H-NMR, FTIR, dynamic light scattering-zeta potential, atomic force microscopy, and drug release experiments. Cellular uptake and the antitumor activity of MTX-loaded nanogels were investigated by flow cytometry and MTT assay. Discrete, spherical and uniform nanogels, with sizes about 77–83 nm and a relatively high drug loading (54 ± 4% w/w), showed a low polydispersity and neutral surface charges. The MTX-loaded nanogels, unlike empty nanogels, lowered viability of HepG2 cells; the nanogels demonstrated cell-cycle arrest and apoptosis comparably higher than MTX as free drug that was shown to be through i) cellular uptake of the nanogels by clathrin-mediated transport and ii) endosomolytic activity of the nanogels in HepG2 cells. These findings indicate the potential antitumor application of this preparation, which has to be investigated in-vivo. - Highlights: • Nanogel synthesis through chemical crosslinking of the transition metal ion coordinated polymer self-assembly • An enhanced cytocompatibility if compared to unmodified polymer • A noticeable endocytic cellular internalization and endosomolytic activity • A specific antitumor cytotoxicity, cell cycle arrest and apoptosis in resistant tumor cells.

  15. A novel HDAC inhibitor, CG200745, inhibits pancreatic cancer cell growth and overcomes gemcitabine resistance.

    Science.gov (United States)

    Lee, Hee Seung; Park, Soo Been; Kim, Sun A; Kwon, Sool Ki; Cha, Hyunju; Lee, Do Young; Ro, Seonggu; Cho, Joong Myung; Song, Si Young

    2017-01-30

    Pancreatic cancer is predominantly lethal, and is primarily treated using gemcitabine, with increasing resistance. Therefore, novel agents that increase tumor sensitivity to gemcitabine are needed. Histone deacetylase (HDAC) inhibitors are emerging therapeutic agents, since HDAC plays an important role in cancer initiation and progression. We evaluated the antitumor effect of a novel HDAC inhibitor, CG200745, combined with gemcitabine/erlotinib on pancreatic cancer cells and gemcitabine-resistant pancreatic cancer cells. Three pancreatic cancer-cell lines were used to evaluate the antitumor effect of CG200745 combined with gemcitabine/erlotinib. CG200745 induced the expression of apoptotic proteins (PARP and caspase-3) and increased the levels of acetylated histone H3. CG200745 with gemcitabine/erlotinib showed significant growth inhibition and synergistic antitumor effects in vitro. In vivo, gemcitabine/erlotinib and CG200745 reduced tumor size up to 50%. CG200745 enhanced the sensitivity of gemcitabine-resistant pancreatic cancer cells to gemcitabine, and decreased the level of ATP-binding cassette-transporter genes, especially multidrug resistance protein 3 (MRP3) and MRP4. The novel HDAC inhibitor, CG200745, with gemcitabine/erlotinib had a synergistic anti-tumor effect on pancreatic cancer cells. CG200745 significantly improved pancreatic cancer sensitivity to gemcitabine, with a prominent antitumor effect on gemcitabine-resistant pancreatic cancer cells. Therefore, improved clinical outcome is expected in the future.

  16. Antitumoral, antioxidant, and antimelanogenesis potencies of Hawthorn, a potential natural agent in the treatment of melanoma.

    Science.gov (United States)

    Mustapha, Nadia; Mokdad-Bzéouich, Imèn; Maatouk, Mouna; Ghedira, Kamel; Hennebelle, Thierry; Chekir-Ghedira, Leila

    2016-06-01

    The lack of an efficient agent that does not have the disadvantage of low activity (kojic acid), high cytotoxicity, and mutagenicity (hydroquinone), poor skin penetration (arbutin), or low stability in formulation (glabridin) led us to continue our research on new antipigmentation/skin-lightening agents. Therefore, research of natural products that can modulate the metabolism of pigmentation is of great interest. Otherwise, malignant melanoma is one of the most aggressive forms of skin cancer, with high metastatic potential, and currently, there is no effective chemotherapy against invasive melanoma. Therefore, it is necessary to develop new drugs with potent activity and weak side effects against melanoma. The in-vitro anticancer effect of hawthorn was analyzed against B16F10 melanoma cells using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The effect of isolated compounds from hawthorn on melanogenesis in B16F10 melanoma cells was investigated by measuring the amounts of melanin and tyrosinase spectrophotometrically at 475 nm. Balb/c mice models inoculated with B16F10 mouse tumor cells were used to evaluate the in-vivo antitumoral potential of hawthorn by assessing its effect on the growth of transplanted tumors. The antioxidant potential of tested samples was evaluated in B16F10 and primary human keratinocyte cells using a cellular antioxidant activity assay. Hawthorn tested samples inhibited effectively the growth of melanoma cells in vitro. Furthermore, it appears that tested samples from hawthorn reduced melanogenesis by inhibiting the tyrosinase activity of B16F10 cells in a dose-dependent manner. In-vivo studies showed that hawthorn total oligomer flavonoids extract treatment at a dose of 150 mg/kg body weight for 21 days in implanted tumor mice resulted in significant inhibition of the tumor growth volume and weight. In addition, tested samples showed significant cellular antioxidant capacity against the reactive oxygen species

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

    Directory of Open Access Journals (Sweden)

    Kristian Michael Hargadon

    2013-07-01

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

  18. GADD45ß, an anti-tumor gene, inhibits avian leukosis virus subgroup J replication in chickens

    Science.gov (United States)

    Avian leukosis virus subgroup J (ALV-J) is a retrovirus that induces neoplasia, hepatomegaly, immunosuppression and poor performance in chickens. The tumorigenic and pathogenic mechanisms of ALV-J remain a hot topic. To explore anti-tumor genes that confer genetic resistance to ALV-J infection in ch...

  19. CCL3 Enhances Antitumor Immune Priming in the Lymph Node via IFNγ with Dependency on Natural Killer Cells

    Directory of Open Access Journals (Sweden)

    Frederick Allen

    2017-10-01

    Full Text Available Lymph node (LN plays a critical role in tumor cell survival outside of the primary tumor sites and dictates overall clinical response in many tumor types (1, 2. Previously, we and others have demonstrated that CCL3 plays an essential role in orchestrating T cell—antigen-presenting cell (APC encounters in the draining LN following vaccination, and such interactions enhance the magnitude of the memory T cell pool (3–5. In the current study, we investigate the cellular responses in the tumor-draining lymph nodes (TDLNs of a CCL3-secreting CT26 colon tumor (L3TU as compared to wild-type tumor (WTTU during the priming phase of an antitumor response (≤10 days. In comparison to WTTU, inoculation of L3TU resulted in suppressed tumor growth, a phenomenon that is accompanied by altered in vivo inflammatory responses on several fronts. Autologous tumor-derived CCL3 (aCCL3 secretion by L3TU bolstered the recruitment of T- and B-lymphocytes, tissue-migratory CD103+ dendritic cells (DCs, and CD49b+ natural killer (NK cells, resulting in significant increases in the differentiation and activation of multiple Interferon-gamma (IFNγ-producing leukocytes in the TDLN. During this early phase of immune priming, NK cells constitute the major producers of IFNγ in the TDLN. CCL3 also enhances CD8+ T cell proliferation and differentiation by augmenting DC capacity to drive T cell activation in the TDLN. Our results revealed that CCL3-dependent IFNγ production and CCL3-induced DC maturation drive the priming of effective antitumor immunity in the TDLN.

  20. The role of radiotherapy for the induction of antitumor immune responses

    International Nuclear Information System (INIS)

    Multhoff, G.; Helmholtz-Zentrum Muenchen; Gaipl, U.S.; Niedermann, G.

    2012-01-01

    Effective radiotherapy is aimed to control the growth of the primary carcinoma and to induce a long-term specific antitumor immune response against the primary tumor, recurrence and metastases. The contribution covers the following issues: T cells and tumor specific immune responses, dendritic cells (DCs) start adaptive immune responses, NK (natural killer) cells for HLA independent tumor control, abscopal effects of radiotherapy, combination of radiotherapy and immune therapy, radiotherapy contribution to the induction of immunogenic cell death, combinability of radiotherapy and DC activation, combinability of radiotherapy and NK cell therapy. It turns out that the combination of radio-chemotherapy and immune therapy can change the microenvironment initiating antitumor immune reactions that inhibit the recurrence risk and the development of metastases.

  1. Potent antitumor bifunctional DNA alkylating agents, synthesis and biological activities of 3a-aza-cyclopenta[a]indenes.

    Science.gov (United States)

    Kakadiya, Rajesh; Dong, Huajin; Lee, Pei-Chih; Kapuriya, Naval; Zhang, Xiuguo; Chou, Ting-Chao; Lee, Te-Chang; Kapuriya, Kalpana; Shah, Anamik; Su, Tsann-Long

    2009-08-01

    A series of bifunctional DNA interstrand cross-linking agents, bis(hydroxymethyl)- and bis(carbamates)-8H-3a-azacyclopenta[a]indene-1-yl derivatives were synthesized for antitumor evaluation. The preliminary antitumor studies revealed that these agents exhibited potent cytotoxicity in vitro and antitumor therapeutic efficacy against human tumor xenografts in vivo. Furthermore, these derivatives have little or no cross-resistance to either Taxol or Vinblastine. Remarkably, complete tumor remission in nude mice bearing human breast carcinoma MX-1 xenograft by 13a,b and 14g,h and significant suppression against prostate adenocarcinoma PC3 xenograft by 13b were achieved at the maximum tolerable dose with relatively low toxicity. In addition, these agents induce DNA interstrand cross-linking and substantial G2/M phase arrest in human non-small lung carcinoma H1299 cells. The current studies suggested that these agents are promising candidates for preclinical studies.

  2. A novel STAT inhibitor, OPB-31121, has a significant antitumor effect on leukemia with STAT-addictive oncokinases

    International Nuclear Information System (INIS)

    Hayakawa, F; Sugimoto, K; Harada, Y; Hashimoto, N; Ohi, N; Kurahashi, S; Naoe, T

    2013-01-01

    Signal transduction and activator of transcription (STAT) proteins are extracellular ligand-responsive transcription factors that mediate cell proliferation, apoptosis, differentiation, development and the immune response. Aberrant signals of STAT induce uncontrolled cell proliferation and apoptosis resistance and are strongly involved in cancer. STAT has been identified as a promising target for antitumor drugs, but to date most trials have not been successful. Here, we demonstrated that a novel STAT inhibitor, OPB-31121, strongly inhibited STAT3 and STAT5 phosphorylation without upstream kinase inhibition, and induced significant growth inhibition in various hematopoietic malignant cells. Investigation of various cell lines suggested that OPB-31121 is particularly effective against multiple myeloma, Burkitt lymphoma and leukemia harboring BCR–ABL, FLT3/ITD and JAK2 V617F, oncokinases with their oncogenicities dependent on STAT3/5. Using an immunodeficient mouse transplantation system, we showed the significant antitumor effect of OPB-31121 against primary human leukemia cells harboring these aberrant kinases and its safety for normal human cord blood cells. Finally, we demonstrated a model to overcome drug resistance to upstream kinase inhibitors with a STAT inhibitor. These results suggested that OPB-31121 is a promising antitumor drug. Phase I trials have been performed in Korea and Hong Kong, and a phase I/II trial is underway in Japan

  3. Antitumor Activity of a 5-Hydroxy-1H-Pyrrol-2-(5H-One-Based Synthetic Small Molecule In Vitro and In Vivo.

    Directory of Open Access Journals (Sweden)

    Yunyun Geng

    Full Text Available Alternative chemo-reagents are in great demand because chemotherapy resistance is one of the major challenges in current cancer treatment. 5-hydoxy-1H-pyrrol-2-(5H-one is an important N-heterocyclic scaffold that is present in natural products and medicinal chemistry. However, its antitumor activity has not been systematically explored. In this study, we screened a panel of 5-hydoxy-1H-pyrrol-2-(5H-one derivatives and identified compound 1d as possessing strong anti-proliferative activity in multiple cancer cell lines. Cell cycle analysis revealed that 1d can induce S-phase cell cycle arrest and that HCT116 was sensitive to 1d-induced apoptosis. Further analysis indicated that 1d preferentially induced DNA damage and p53 activation in HCT116 cells and that 1d-induced apoptosis is partly dependent on p53. Furthermore, we showed that 1d significantly suppressed tumor growth in xenograft tumor models in vivo. Taken together, our results suggest that 5-hydoxy-1H-pyrrol-2-(5H-one derivatives bear potential antitumor activity and that 1d is an effective agent for cancer treatment.

  4. Triclosan treatment decreased the antitumor effect of sorafenib on hepatocellular carcinoma cells

    Directory of Open Access Journals (Sweden)

    Wu M

    2018-05-01

    Full Text Available Man Wu,1,2 Guanren Zhao,2 Xiaomei Zhuang,1 Tianhong Zhang,1 Ce Zhang,2 Wenpeng Zhang,1 Zhenqing Zhang1 1State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Institute of Pharmacology and Toxicology, Beijing, China; 2Department of Pharmacy, The 309th Hospital of PLA, Beijing, China Background: Triclosan is a widely applied antimicrobial agent which affects the endocrine system and homeostasis; it may also promote the cirrhosis and hepatocellular carcinoma (HCC growth in a mice model. The exact roles of triclosan in regulating human hepatocellular carcinoma development and treatment remain unknown. Methods: MHCC97-H, a highly aggressive HCC cell line, was treated with indicated concentration of triclosan or sorafenib. The expression of drug-resistance genes was examined by qPCR. The clearance or metabolism of sorafenib was determined by liquid chromatograph-mass spectrometer/mass spectrometer (LC-MS/MS. MTT assay was used to examine the MHCC97-H cell proliferation. Nude mice were used to exam the anti-tumor effect of sorafenib on subcutaneous and intrahepatic growth of MHCC97-H cells. Results: In the present study, triclosan could induce the expression of drug-resistance genes in MHCC97-H cells (a highly aggressive HCC cell line, accelerate the clearance of sorafenib, and attenuate the anti-proliferation effect of this molecular targeted agent in MHCC97-H cells. Triclosan decreased the antitumor effect of sorafenib on subcutaneous and intrahepatic growth of MHCC97-H in nude mice. Conclusion: By discovering the fact that triclosan treatment enhances sorafenib resistance in HCC cells, this work suggests exposure of triclosan is detrimental to HCC patients during chemotherapy. Keywords: HCC, triclosan, sorafenib resistance, drug clearance 

  5. Addressing the Natural Antibiotic Resistome in Studies of Soil Resistance

    Science.gov (United States)

    The environment is recognized as a source and a reservoir of antibiotic resistance (AR). Many antibiotic compounds are derived from bacteria and fungi that are naturally present in the environment. These microbes carry genes encoding resistance to the antibiotic that they produce and their resistanc...

  6. Antitumoral activity of marine organism

    International Nuclear Information System (INIS)

    Valdes Iglesias, O; Perez Gil, R; Colom, Y

    2010-01-01

    The study of the natural products from marine organism constitute a relatively recent scientific researcher field with high potentialities tanking in consideration that the oceans cover the three of the four parts of the earth. Poryphera and Bryozoans have been the Phylum more studied owning to the vulnerability, their soft body, their habitat on rocks, their slow movement and bright colors, for these reason these organisms are able to produce chemical substances as defense methods against depredators. Same mechanism is exhibit by the seaweeds with the production of secondary metabolites . In the present communication are exposed the main results obtained on the world a Cuba until the present in the looking for of substances with antitumor action from marine organism

  7. Natural variation of rice blast resistance gene Pi-d2

    Science.gov (United States)

    Studying natural variation of rice resistance (R) genes in cultivated and wild rice relatives can predict resistance stability to rice blast fungus. In the present study, the protein coding regions of rice R gene Pi-d2 in 35 rice accessions of subgroups, aus (AUS), indica (IND), temperate japonica (...

  8. Anti-tumor effects of an engineered “killer” transfer RNA

    International Nuclear Information System (INIS)

    Zhou, Dong-hui; Lee, Jiyoung; Frankenberger, Casey; Geslain, Renaud; Rosner, Marsha; Pan, Tao

    2012-01-01

    Highlights: ► tRNA with anti-cancer effects. ► tRNA induced protein misfolding. ► tRNA as anti-tumor agent. -- Abstract: A hallmark of cancer cells is their ability to continuously divide; and rapid proliferation requires increased protein translation. Elevating levels of misfolded proteins can elicit growth arrest due to ER stress and decreased global translation. Failure to correct prolonged ER stress eventually results in cell death via apoptosis. tRNA Ser (AAU) is an engineered human tRNA Ser with an anticodon coding for isoleucine. Here we test the possibility that tRNA Ser (AAU) can be an effective killing agent of breast cancer cells and can effectively inhibit tumor-formation in mice. We found that tRNA Ser (AAU) exert strong effects on breast cancer translation activity, cell viability, and tumor formation. Translation is strongly inhibited by tRNA Ser (AAU) in both tumorigenic and non-tumorigenic cells. tRNA Ser (AAU) significantly decreased the number of viable cells over time. A short time treatment with tRNA Ser (AAU) was sufficient to eliminate breast tumor formation in a xenograft mouse model. Our results indicate that tRNA Ser (AAU) can inhibit breast cancer metabolism, growth and tumor formation. This RNA has strong anti-cancer effects and presents an opportunity for its development into an anti-tumor agent. Because tRNA Ser (AAU) corrupts the protein synthesis mechanism that is an integral component of the cell, it would be extremely difficult for tumor cells to evolve and develop resistance against this anti-tumor agent.

  9. Biomarkers and mechanisms of natural disease resistance in dairy cows

    NARCIS (Netherlands)

    Altena, van S.E.C.

    2016-01-01

    The aim of this thesis was to define and test biomarkers for disease resistance in dairy cows and to determine the underlying mechanism in natural disease resistance. The health status of the cows is an important issue in dairy farming. Due to the mandatory reduction in the use of antibiotics,

  10. Natural Killer Dendritic Cells Enhance Immune Responses Elicited by α-Galactosylceramide-Stimulated Natural Killer T Cells

    Directory of Open Access Journals (Sweden)

    Sung Won Lee

    2013-01-01

    Full Text Available Natural killer dendritic cells (NKDCs possess potent anti-tumor activity, but the cellular effect of NKDC interactions with other innate immune cells is unclear. In this study, we demonstrate that the interaction of NKDCs and natural killer T (NKT cells is required for the anti-tumor immune responses that are elicited by α-galactosylceramide (α-GC in mice. The rapid and strong expression of interferon-γ by NKDCs after α-GC stimulation was dependent on NKT cells. Various NK and DC molecular markers and cytotoxic molecules were up-regulated following α-GC administration. This up-regulation could improve NKDC presentation of tumor antigens and increase cytotoxicity against tumor cells. NKDCs were required for the stimulation of DCs, NK cells, and NKT cells. The strong anti-tumor immune responses elicited by α-GC may be due to the down-regulation of regulatory T cells. Furthermore, the depletion of NKDCs dampened the tumor clearance mediated by α-GC-stimulated NKT cells in vivo. Taken together, these results indicate that complex interactions of innate immune cells might be required to achieve optimal anti-tumor immune responses during the early stages of tumorigenesis.

  11. Priming of plant resistance by natural compounds. Hexanoic acid as a model

    Directory of Open Access Journals (Sweden)

    Paz eAranega Bou

    2014-10-01

    Full Text Available Some alternative control strategies of currently emerging plant diseases are based on the use of resistance inducers. This review highlights the recent advances made in the characterization of natural compounds that induce resistance by a priming mechanism. These include vitamins, chitosans, oligogalacturonides, volatile organic compounds, azelaic and pipecolic acid, among others. Overall, other than providing novel disease control strategies that meet environmental regulations, natural priming agents are valuable tools to help unravel the complex mechanisms underlying the induced resistance phenomenon. The data presented in this review reflect the novel contributions made from studying these natural plant inducers, with special emphasis placed on hexanoic acid (Hx, proposed herein as a model tool for this research field. Hx is a potent natural priming agent of proven efficiency in a wide range of host plants and pathogens. It can early activate broad-spectrum defenses by inducing callose deposition and the SA and JA pathways. Later it can prime pathogen-specific responses according to the pathogen’s lifestyle. Interestingly, Hx primes redox-related genes to produce an anti-oxidant protective effect, which might be critical for limiting the infection of necrotrophs. Our Hx-induced resistance (Hx-IR findings also strongly suggest that it is an attractive tool for the molecular characterization of the plant alarmed state, with the added advantage of it being a natural compound.

  12. Fraction From Lycium barbarum Polysaccharides Reduces Immunotoxicity and Enhances Antitumor Activity of Doxorubicin in Mice.

    Science.gov (United States)

    Deng, Xiangliang; Luo, Shuang; Luo, Xia; Hu, Minghua; Ma, Fangli; Wang, Yuanyuan; Zhou, Lian; Huang, Rongrong

    2018-01-01

    The aim of the present study was to investigate whether fraction from Lycium barbarum polysaccharide (LBP) could reduce immunotoxicity and enhance antitumor activity of doxorubicin (Dox) in mice. A water-soluble LBP fraction, designated LBP3, was isolated from edible Chinese herbal Lycium barbarum and used in this study. To investigate the effect of LBP3 on Dox-induced immunotoxicity, tumor-free mice were used and treated with either normal saline, Dox, or Dox plus LBP3. To investigate the effect of LBP3 on antitumor activity of Dox, H22 tumor-bearing mice were used and treated with either normal saline, Dox, LBP3, or Dox plus LBP3. The results showed that LBP3 did not protect against the body weight loss caused by Dox, but it promoted the recovery of body weight starting at day 5 after Dox treatment in tumor-free mice. LBP3 also improved peripheral blood lymphocyte counts, promoted cell cycle recovery in bone marrow cells, and restored the cytotoxicity of natural killer cells. Furthermore, in H22 tumor-bearing mice, LBP3 enhanced antitumor activity of Dox and improved peripheral blood lymphocyte counts and the cytotoxicity of splenocytes. In brief, our results demonstrated that LBP3 could reduce the immunotoxicity and enhance antitumor activity of Dox.

  13. Microbial Resistance to Triclosan: A Case Study in Natural Selection

    Science.gov (United States)

    Serafini, Amanda; Matthews, Dorothy M.

    2009-01-01

    Natural selection is the mechanism of evolution caused by the environmental selection of organisms most fit to reproduce, sometimes explained as "survival of the fittest." An example of evolution by natural selection is the development of bacteria that are resistant to antimicrobial agents as a result of exposure to these agents. Triclosan, which…

  14. The role of natural environments in the evolution of resistance traits in pathogenic bacteria

    OpenAIRE

    Martinez, Jose L.

    2009-01-01

    Antibiotics are among the most valuable compounds used for fighting human diseases. Unfortunately, pathogenic bacteria have evolved towards resistance. One important and frequently forgotten aspect of antibiotics and their resistance genes is that they evolved in non-clinical (natural) environments before the use of antibiotics by humans. Given that the biosphere is mainly formed by micro-organisms, learning the functional role of antibiotics and their resistance elements in nature has releva...

  15. Partial characterization, antioxidant and antitumor activities of polysaccharides from Philomycusbilineatus.

    Science.gov (United States)

    He, Rongjun; Ye, Jiaming; Zhao, Yuejun; Su, Weike

    2014-04-01

    Four polysaccharides (PBP60-A, PBP60-B, PBP60-C and PBP60-D) were purified from slug (Philomycusbilineatus) by ion-exchange chromatography. The antioxidant activities were studied by ABTS, DPPH, hydroxyl radical, superoxide radical and reducing power assay. In vitro antitumor activities were evaluated by MTT assay. Results demonstrated that PBP60-A was mainly composed of Man, Rha, Glc, Gal, Xyl and Fuc in a mole ratio of 6.13:3.08:8.97:5.22:2.46:1.13. PBP60-B was composed of Man, GlcN, Rha, GalN, GlcU, Glc, Gal, Xyl and Fuc in a mole ratio of 0.90:0.31:1.15:0.37:0.24:1.02:3.84:0.93:1.99. PBP60-C and PBP60-D were composed of Man, GlcN, Rha, GalN, GlcU, Glc, Gal, Xyl, Fuc and an unknown monosaccharide. Antioxidant tests indicated that four polysaccharides exhibited significant antioxidant activities in a dose-dependent manner. PBP60-D presented relative stronger antioxidant activity. PBP60-C showed higher antitumor activity against A549 and MCF-7 cells in vitro. At concentration of500 μg/mL, the antitumor activities of PBP60-C on theA549 and MCF-7 cells were 65.30% and 42.45%, respectively. These results indicated that polysaccharides from Philomycusbilineatus could be explored as potential natural antioxidants and cancer prevention agents. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Andrographolide enhanced 5-fluorouracil-induced antitumor effect in colorectal cancer via inhibition of c-MET pathway

    Directory of Open Access Journals (Sweden)

    Su M

    2017-11-01

    Full Text Available Meng Su,1 Baoli Qin,1 Fang Liu,2 Yuze Chen,2 Rui Zhang2 1Department of Internal Medicine, 2Department of Colorectal Surgery, Cancer Hospital of China Medical University, Liaoning Cancer Hospital and Institute, Liaoning, China Abstract: Colorectal cancer (CRC is the third most common malignant neoplasm worldwide. 5-Fluorouracil (5-Fu is the most important chemotherapeutic drug used for the treatment of CRC. However, resistance to 5-Fu therapies is a growing concern in CRC clinical practice recently. Andrographolide (Andro is a main bioactive constituent of the herb Andrographis paniculata, which has various biological effects including anti-inflammation and antitumor activities. In the present study, we investigated the effects of combined Andro with 5-Fu against CRC HCT-116 cells. In vitro studies showed that Andro synergistically enhanced the anti-proliferation effect of 5-Fu on HCT-116 cells due to increased apoptotic cells. Meanwhile, results of the enzyme linked immunosorbent assay indicated that the level of phosphorylated cellular-mesenchymal to epithelial transition factor (p-MET was decreased by the combination treatment. Further study suggested that Andro promoted the antitumor effect of 5-Fu by downregulating the level of p-MET. In conclusion, these results confirmed the synergistic antitumor activity of Andro on CRC and provide evidence for possible clinical application of Andro for enhancing the antitumor effect of 5-Fu in CRC treatment. Keywords: Andro, 5-Fu, HCT-116 cells, apoptosis, p-MET

  17. Sensitivity to ionizing radiation and chemotherapeutic agents in gemcitabine-resistant human tumor cell lines

    NARCIS (Netherlands)

    van Bree, Chris; Castro Kreder, Natasja; Loves, Willem J. P.; Franken, Nicolaas A. P.; Peters, Godefridus J.; Haveman, Jaap

    2002-01-01

    Purpose: To determine cross-resistance to anti-tumor treatments in 2',2'difluorodeoxycytidine (dFdC, gemcitabine)-resistant human tumor cells. Methods and Materials: Human lung carcinoma cells SW-1573 (SWp) were made resistant to dFdC (SWg). Sensitivity to cisplatin (cDDP), paclitaxel,

  18. Microencapsulation of anti-tumor, antibiotic and thrombolytic drugs in microgravity

    Science.gov (United States)

    Morrison, Dennis R.; Mosier, Benjamin; Cassanto, John

    1994-01-01

    Encapsulation of cytotoxic or labile drugs enables targeted delivery and sustained release kinetics that are not available with intravenous injection. A new liquid-liquid diffusion process has been developed for forming unique microcapsules that contain both aqueous and hydrocarbon soluble drugs. Microgravity experiments, on sounding rockets (1989-92) and Shuttle missions STS-52 (1992) and STS-56 (1993) using an automated Materials Dispersion Apparatus, produced multi-lamellar microcapsules containing both Cis-platinum (anti-tumor drug) and iodinated poppy seed oil (a radiocontrast medium), surrounded by a polyglyceride skin. Microcapsules formed with amoxicillin (antibiotic) or urokinase (a clot dissolving enzyme), co-encapsulated with IPO, are still intact after two years. Microcapsules were formed with the drug so concentrated that crystals formed inside. Multi-layered microspheres, with both hydrophobic drug compartments, can enable diffusion of complementary drugs from the same microcapsule, e.g. antibiotics and immuno-stimulants to treat resistant infections or multiple fibrinolytic drugs to dissolve emboli. Co-encapsulation of enough radio-contrast medium enables oncologists to monitor the delivery of anti-tumor microcapsules to target tumors using computerized tomography and radiography that would track the distribution of microcapsules after release from the intra-arterial catheter. These microcapsules could have important applications in chemotheraphy of certain liver, kidney, brain and other tumors.

  19. Transgenerational Effects Alter Plant Defense and Resistance in Nature

    Science.gov (United States)

    Colicchio, Jack

    2017-01-01

    Trichomes, or leaf hairs, are epidermal extensions that take a variety of forms and perform many functions in plants, including herbivore defense. In this study, I document genetically determined variation, within-generation plasticity, and a direct role of trichomes in herbivore defense for Mimulus guttatus. After establishing the relationship between trichomes and herbivory, I test for transgenerational effects of wounding on trichome density and herbivore resistance. Patterns of inter-annual variation in herbivore density and the high cost of plant defense makes plant-herbivore interactions a system in which transgenerational phenotypic plasticity (TPP) is apt to evolve. Here, I demonstrate that parental damage alters offspring trichome density and herbivore resistance in nature. Moreover, this response varies between populations. This is among the first studies to demonstrate that TPP contributes to variation in nature, and also suggests that selection can modify TPP in response to local conditions. PMID:28102915

  20. Evaluation of antitumor, immunomodulatory and free radical scavenging effects of a new herbal prescription seaweed complex preparation

    Science.gov (United States)

    Liu, Xin; Shao, Changlun; Kong, Wenwen; Fang, Yuchun; Wang, Changyun

    2013-09-01

    Seaweed Complex Preparation (SCP) is a clinical traditional Chinese medicine preparation which is composed of seven traditional Chinese herbs, and it has been used for treatment of lung cancer, liver cancer and digestive cancer. However, little information is available about the pharmacodynamic basis. The antitumor, immunomodulatory and free radical scavenging effects of SCP were evaluated in this study. Transplanted tumor in vivo method was used to determine the antitumor effect. The effects on splenocyte proliferation and phagocytosis of macrophages in tumor-bearing mice were measured by the MTT method and the phagocytizing cock red blood cell (CRBC) method respectively. The scavenging activities of SCP on DPPH and hydroxyl radicals in vitro were investigated. It was found that the medium-dose and high-dose of SCP could significantly inhibit the growth of transplanted hepatic tumor of murine hepatocarcinoma cell line H22, and promote proliferation of splenocytes and phagocytosis of macrophages. SCP possessed noticeable scavenging activities on DPPH and hydroxyl radicals. The antitumor effects of SCP might be achieved by improving immune system and scavenging free radicals, which is in accordance with the viewpoint of traditional Chinese medicine in promoting the body resistance and eliminating pathogenic factors for cancer treatment.

  1. Anti-tumor effects of an engineered 'killer' transfer RNA

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Dong-hui [Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60637 (United States); Lee, Jiyoung; Frankenberger, Casey [Ben May Department for Cancer Research, University of Chicago, Chicago, IL 60637 (United States); Geslain, Renaud, E-mail: rgeslain@depaul.edu [Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60637 (United States); Department of Biology, DePaul University, Chicago, IL 60614 (United States); Rosner, Marsha, E-mail: m-rosner@uchicago.edu [Ben May Department for Cancer Research, University of Chicago, Chicago, IL 60637 (United States); Pan, Tao, E-mail: taopan@uchicago.edu [Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60637 (United States)

    2012-10-12

    Highlights: Black-Right-Pointing-Pointer tRNA with anti-cancer effects. Black-Right-Pointing-Pointer tRNA induced protein misfolding. Black-Right-Pointing-Pointer tRNA as anti-tumor agent. -- Abstract: A hallmark of cancer cells is their ability to continuously divide; and rapid proliferation requires increased protein translation. Elevating levels of misfolded proteins can elicit growth arrest due to ER stress and decreased global translation. Failure to correct prolonged ER stress eventually results in cell death via apoptosis. tRNA{sup Ser}(AAU) is an engineered human tRNA{sup Ser} with an anticodon coding for isoleucine. Here we test the possibility that tRNA{sup Ser}(AAU) can be an effective killing agent of breast cancer cells and can effectively inhibit tumor-formation in mice. We found that tRNA{sup Ser}(AAU) exert strong effects on breast cancer translation activity, cell viability, and tumor formation. Translation is strongly inhibited by tRNA{sup Ser}(AAU) in both tumorigenic and non-tumorigenic cells. tRNA{sup Ser}(AAU) significantly decreased the number of viable cells over time. A short time treatment with tRNA{sup Ser}(AAU) was sufficient to eliminate breast tumor formation in a xenograft mouse model. Our results indicate that tRNA{sup Ser}(AAU) can inhibit breast cancer metabolism, growth and tumor formation. This RNA has strong anti-cancer effects and presents an opportunity for its development into an anti-tumor agent. Because tRNA{sup Ser}(AAU) corrupts the protein synthesis mechanism that is an integral component of the cell, it would be extremely difficult for tumor cells to evolve and develop resistance against this anti-tumor agent.

  2. In vitro testing of curcumin based composites coatings as antitumoral systems against osteosarcoma cells

    Science.gov (United States)

    Tirca, I.; Mitran, V.; Marascu, V.; Brajnicov, S.; Ion, V.; Stokker-Cheregi, F.; Popovici, I. A.; Cimpean, A.; Dinca, V.; Dinescu, M.

    2017-12-01

    In this work, we propose a new design for biodegradable composite coatings obtained by laser methods, which are aimed at evaluating the effects of active antitumoral elements on osteosarcoma cells. Our approach relies on embedding curcumin, which is a natural polyphenol having antitumoral properties, within biodegradable copolymer coatings (i.e. polyvinyl alcohol-polyethylene glycol - PVA-PEG) by using matrix assisted pulsed laser evaporation (MAPLE). The structural and morphological characteristics of the coatings were tailored by using different solvents (water, ethanol, benzene, dimethylsufoxide) as deposition matrix. The morphological characteristics of the resulting films were investigated by atomic force microscopy (AFM), whereas their chemical composition was characterized by Fourier transform infrared spectroscopy (FTIR). These characteristics were correlated with the degradation behavior by using ellipsometry (SE) and AFM measurements data. The in vitro study of the MG-63 osteosarcoma cell behavior indicates that the developed hybrid coatings significantly decreased osteosarcoma cell viability and proliferation potential. The physico-chemical characteristics of the thin films, along with the preliminary in vitro analyses, suggest that our developed polymeric hybrid coatings represent an efficient way to tackle the design of antitumoral surfaces, with applications in biomedicine.

  3. Transgenerational effects alter plant defence and resistance in nature.

    Science.gov (United States)

    Colicchio, J

    2017-04-01

    Trichomes, or leaf hairs, are epidermal extensions that take a variety of forms and perform many functions in plants, including herbivore defence. In this study, I document genetically determined variation, within-generation plasticity, and a direct role of trichomes in herbivore defence for Mimulus guttatus. After establishing the relationship between trichomes and herbivory, I test for transgenerational effects of wounding on trichome density and herbivore resistance. Patterns of interannual variation in herbivore density and the high cost of plant defence makes plant-herbivore interactions a system in which transgenerational phenotypic plasticity (TPP) is apt to evolve. Here, I demonstrate that parental damage alters offspring trichome density and herbivore resistance in nature. Moreover, this response varies between populations. This is among the first studies to demonstrate that TPP contributes to variation in nature, and also suggests that selection can modify TPP in response to local conditions. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

  4. Overcoming tumor resistance by heterologous adeno-poxvirus combination therapy

    Directory of Open Access Journals (Sweden)

    Markus Vähä-Koskela

    2014-01-01

    Full Text Available Successful cancer control relies on overcoming resistance to cell death and on activation of host antitumor immunity. Oncolytic viruses are particularly attractive in this regard, as they lyse infected tumor cells and trigger robust immune responses during the infection. However, repeated injections of the same virus promote antiviral rather than antitumor immunity and tumors may mount innate antiviral defenses to restrict oncolytic virus replication. In this article, we have explored if alternating the therapy virus could circumvent these problems. We demonstrate in two virus-resistant animal models a substantial delay in antiviral immune- and innate cellular response induction by alternating injections of two immunologically distinct oncolytic viruses, adenovirus, and vaccinia virus. Our results are in support of clinical development of heterologous adeno-/vaccinia virus therapy of cancer.

  5. A Chemoinformatics Approach to the Discovery of Lead-Like Molecules from Marine and Microbial Sources En Route to Antitumor and Antibiotic Drugs

    Science.gov (United States)

    Pereira, Florbela; Latino, Diogo A. R. S.; Gaudêncio, Susana P.

    2014-01-01

    The comprehensive information of small molecules and their biological activities in the PubChem database allows chemoinformatic researchers to access and make use of large-scale biological activity data to improve the precision of drug profiling. A Quantitative Structure–Activity Relationship approach, for classification, was used for the prediction of active/inactive compounds relatively to overall biological activity, antitumor and antibiotic activities using a data set of 1804 compounds from PubChem. Using the best classification models for antibiotic and antitumor activities a data set of marine and microbial natural products from the AntiMarin database were screened—57 and 16 new lead compounds for antibiotic and antitumor drug design were proposed, respectively. All compounds proposed by our approach are classified as non-antibiotic and non-antitumor compounds in the AntiMarin database. Recently several of the lead-like compounds proposed by us were reported as being active in the literature. PMID:24473174

  6. Secretion of Rhoptry and Dense Granule Effector Proteins by Nonreplicating Toxoplasma gondii Uracil Auxotrophs Controls the Development of Antitumor Immunity.

    Directory of Open Access Journals (Sweden)

    Barbara A Fox

    2016-07-01

    Full Text Available Nonreplicating type I uracil auxotrophic mutants of Toxoplasma gondii possess a potent ability to activate therapeutic immunity to established solid tumors by reversing immune suppression in the tumor microenvironment. Here we engineered targeted deletions of parasite secreted effector proteins using a genetically tractable Δku80 vaccine strain to show that the secretion of specific rhoptry (ROP and dense granule (GRA proteins by uracil auxotrophic mutants of T. gondii in conjunction with host cell invasion activates antitumor immunity through host responses involving CD8α+ dendritic cells, the IL-12/interferon-gamma (IFN-γ TH1 axis, as well as CD4+ and CD8+ T cells. Deletion of parasitophorous vacuole membrane (PVM associated proteins ROP5, ROP17, ROP18, ROP35 or ROP38, intravacuolar network associated dense granule proteins GRA2 or GRA12, and GRA24 which traffics past the PVM to the host cell nucleus severely abrogated the antitumor response. In contrast, deletion of other secreted effector molecules such as GRA15, GRA16, or ROP16 that manipulate host cell signaling and transcriptional pathways, or deletion of PVM associated ROP21 or GRA3 molecules did not affect the antitumor activity. Association of ROP18 with the PVM was found to be essential for the development of the antitumor responses. Surprisingly, the ROP18 kinase activity required for resistance to IFN-γ activated host innate immunity related GTPases and virulence was not essential for the antitumor response. These data show that PVM functions of parasite secreted effector molecules, including ROP18, manipulate host cell responses through ROP18 kinase virulence independent mechanisms to activate potent antitumor responses. Our results demonstrate that PVM associated rhoptry effector proteins secreted prior to host cell invasion and dense granule effector proteins localized to the intravacuolar network and host nucleus that are secreted after host cell invasion coordinately

  7. Structure, chain conformation and antitumor activity of a novel polysaccharide from Lentinus edodes.

    Science.gov (United States)

    Yu, Zhang; Ming, Gu; Kaiping, Wang; Zhixiang, Chen; Liquan, Dai; Jingyu, Liu; Fang, Zeng

    2010-12-01

    A water-soluble polysaccharide LT1 was isolated from the basidiocarps of Lentinus edodes by hot water extraction and ethanol precipitations, further purified by gel chromatography. The Mw of LT1 was estimated to be 642 kDa by using HPGPC. Chemical and spectroscopic studies illustrated that LT1 has a backbone chain composed of 1 → 4-linked and 1 → 3-linked glucopyranosyl residues and has branches of single glucosyl stubs at C-6 of β-(1 → 4)-linked glucopyranosyl. AFM and Congo-red test revealed that LT1 existed as triple helix chain in 0.10 M NaOH solution or distilled water. Our studies showed that LT1 presented significant antitumor bioactivities on Sarcoma180 solid tumor cell implanted in BALB/c mice, which implies that LT1 could be potentially applied as a natural antitumor drug. Copyright © 2010 Elsevier B.V. All rights reserved.

  8. Factors underlying the natural resistance of animals against snake venoms

    Directory of Open Access Journals (Sweden)

    H. Moussatché

    1989-01-01

    Full Text Available The existence of mammals and reptilia with a natural resistance to snake venoms is known since a long time. This fact has been subjected to the study by several research workers. Our experiments showed us that in the marsupial Didelphis marsupialis, a mammal highly resistant to the venom of Bothrops jararaca, and other Bothrops venoms, has a genetically origin protein, a alpha-1, acid glycoprotein, now highly purified, with protective action in mice against the jararaca snake venom.

  9. The roots of modern oncology: from discovery of new antitumor anthracyclines to their clinical use.

    Science.gov (United States)

    Cassinelli, Giuseppe

    2016-06-02

    In May 1960, the Farmitalia CEO Dr. Bertini and the director of the Istituto Nazionale dei Tumori of Milan Prof. Bucalossi (talent scout and city's Mayor) signed a research agreement for the discovery and development up to clinical trials of new natural antitumor agents. This agreement can be considered as a pioneering and fruitful example of a translational discovery program with relevant transatlantic connections. Owing to an eclectic Streptomyces, found near Castel del Monte (Apulia), and to the skilled and motivated participants of both institutions, a new natural antitumor drug, daunomycin, was ready for clinical trials within 3 years. Patent interference by the Farmitalia French partner was overcome by the good quality of the Italian drug and by the cooperation between Prof. Di Marco, director of the Istituto Ricerche Farmitalia Research Laboratories for Microbiology and Chemotherapy, and Prof. Karnofsky, head of the Sloan-Kettering Cancer Institute of New York, leading to the first transatlantic clinical trials. The search for daunomycin's sister anthracyclines led to the discovery and development of adriamycin, one of the best drugs born in Milan. This was the second act prologue of the history of Italian antitumor discovery and clinical oncology, which started in July 1969 when Prof. Di Marco sent Prof. Bonadonna the first vials of adriamycin (doxorubicin) to be tested in clinical trials. This article reviews the Milan scene in the 1960s, a city admired and noted for the outstanding scientific achievements of its private and public institutions in drugs and industrial product discovery.

  10. Rhenium–platinum antitumor systems

    Directory of Open Access Journals (Sweden)

    A. V. Shtemenko

    2017-04-01

    Full Text Available This review provides an overlook of design (in short, antitumor and other biological activity of quadruple-bonded cluster dirhenium(III compounds and their synergism with cisplatin. In particular, we describe the work of the rhenium-platinum antitumor system (introduction of rhenium and platinum compounds. Among known metal-based anticancer drugs and drug candidates dirhenium(III compounds differ profoundly due to their strong antiradical and antioxidant properties determined by quadruple bond unsaturation. Such advantages of metal complexes as more expressed redox chemical propertie should be exploited for creating more efficient anticancer drugs. Combination of drugs leads to synergistic effects and/or to lowe­ring toxicity of platinides and is very promising in cancer chemotherapy. The review covers the follo­wing items: design of quadruple bonded dirhenium(III clusters, their spectral and antiradical properties (in short; interaction of the dirhenium(III compounds with lipids and formation of liposomes; interaction of the dirhenium(III compounds with erythrocytes and their antihemolytic activity in the models of hemolytic anemia; anticancer activity of dirhenium clusters and work of the rhenium-platinum antitumor system; antianemic and antioxidant properties of the dirhenium(III compounds in the model of tumor growth; interaction of the dirhenium(III compounds with nucleobases and DNA. Some modern trends in the field of bioinorganic and medicinal chemi­stry are also considered regarding their connection to the rhenium-platinum system efficiency: use of combinational therapy and nanomaterials; involvement of some biologically active ligands and redox-activation strategy, etc.

  11. Variability of resistance in Black Bengal goats naturally infected with Haemonchus contortus.

    Science.gov (United States)

    Kumar, Ratnesh; Ranjan, Sanjeev; Vishnu, P Guru; Negi, Mamta; Senapati, P K; Charita, V Gnani

    2015-03-01

    A total 290 Black Bengal goats (6 buck, 109 doe and 175 kids born from 11 sires) were studied to evaluate the variability of resistance in Black Bengal goats naturally infected with Haemonchus contortus. The variability of resistance in Black Bengal goat was studied for both genetic and non-genetic factors like village, sex, age dam, sire, dam resistance group and offspring resistance group. Male kids have slightly higher resistance than female kids although it was not significant. Resistance of kids was increased as age increases and kid population showed significantly different resistance status among the offspring resistant groups. The doe population showed significantly different LEPG as per the resistance group in all the collections. The present study found that the resistance of kids under sire were varied significantly and observed that the kids under sire 1, 6-8 were significantly more resistant than the kids of the sire 2, 5 and 11 in 3rd collection and it is also noticed that maternal genetic effect has a very little impact on resistance of kids. Males (buck) were most resistant and the kids were least resistant and the resistance of dam was in between the male and kids population.

  12. Antimicrobial peptides with selective antitumor mechanisms: prospect for anticancer applications.

    Science.gov (United States)

    Deslouches, Berthony; Di, Y Peter

    2017-07-11

    In the last several decades, there have been significant advances in anticancer therapy. However, the development of resistance to cancer drugs and the lack of specificity related to actively dividing cells leading to toxic side effects have undermined these achievements. As a result, there is considerable interest in alternative drugs with novel antitumor mechanisms. In addition to the recent approach using immunotherapy, an effective but much cheaper therapeutic option of pharmaceutical drugs would still provide the best choice for cancer patients as the first line treatment. Ribosomally synthesized cationic antimicrobial peptides (AMPs) or host defense peptides (HDP) display broad-spectrum activity against bacteria based on electrostatic interactions with negatively charged lipids on the bacterial surface. Because of increased proportions of phosphatidylserine (negatively charged) on the surface of cancer cells compared to normal cells, cationic amphipathic peptides could be an effective source of anticancer agents that are both selective and refractory to current resistance mechanisms. We reviewed herein the prospect for AMP application to cancer treatment, with a focus on modes of action of cationic AMPs.

  13. Antitumor activity of anti-C-ERC/mesothelin monoclonal antibody in vivo.

    Science.gov (United States)

    Inami, Koichi; Abe, Masaaki; Takeda, Kazuyoshi; Hagiwara, Yoshiaki; Maeda, Masahiro; Segawa, Tatsuya; Suyama, Masafumi; Watanabe, Sumio; Hino, Okio

    2010-04-01

    Mesothelioma is an aggressive cancer often caused by chronic asbestos exposure, and its prognosis is very poor despite the therapies currently used. Due to the long latency period between asbestos exposure and tumor development, the worldwide incidence will increase substantially in the next decades. Thus, novel effective therapies are warranted to improve the prognosis. The ERC/mesothelin gene (MSLN) is expressed in wide variety of human cancers, including mesotheliomas, and encodes a precursor protein cleaved by proteases to generate C-ERC/mesothelin and N-ERC/mesothelin. In this study, we investigated the antitumor activity of C-ERC/mesothelin-specific mouse monoclonal antibody, 22A31, against tumors derived from a human mesothelioma cell line, ACC-MESO-4, in a xenograft experimental model using female BALB/c athymic nude mice. Treatment with 22A31 did not inhibit cell proliferation of ACC-MESO-4 in vitro; however, therapeutic treatment with 22A31 drastically inhibited tumor growth in vivo. 22A31 induced antibody-dependent cell-mediated cytotoxicity by natural killer (NK) cells, but not macrophages, in vitro. Consistently, the F(ab')(2) fragment of 22A31 did not inhibit tumor growth in vivo, nor did it induce antibody-dependent cell mediated cytotoxicity (ADCC) in vitro. Moreover, NK cell depletion diminished the antitumor effect of 22A31. Thus, 22A31 induced NK cell-mediated ADCC and exerted antitumor activity in vivo. 22A31 could have potential as a therapeutic tool to treat C-ERC/mesothelin-expressing cancers including mesothelioma.

  14. Analysis and consideration for the US criteria of nuclear fuel cycle facilities to resist natural disasters

    International Nuclear Information System (INIS)

    Shen Hong

    2013-01-01

    Natural disasters pose a threat to the safety of nuclear facilities. Fukushima nuclear accident tells us that nuclear safety in siting, design and construction shall be strengthened in case of external events caused by natural disasters. This paper first analyzes the DOE criteria of nuclear fuel cycle facilities to resist natural disasters. Then to develop our national criteria for natural disaster resistance of nuclear fuel cycle facilities is suggested, so as to ensure the safety of these facilities. (authors)

  15. Sensitivity to ionizing radiation and chemotherapeutic agents in gemcitabine-resistant human tumor cell lines

    International Nuclear Information System (INIS)

    Bree, Chris van; Kreder, Natasja Castro; Loves, Willem J.P.; Franken, Nicolaas A.P.; Peters, Godefridus J.; Haveman, Jaap

    2002-01-01

    Purpose: To determine cross-resistance to anti-tumor treatments in 2',2'difluorodeoxycytidine (dFdC, gemcitabine)-resistant human tumor cells. Methods and Materials: Human lung carcinoma cells SW-1573 (SWp) were made resistant to dFdC (SWg). Sensitivity to cisplatin (cDDP), paclitaxel, 5-fluorouracil (5-FU), methotrexate (MTX), cytarabine (ara-C), and dFdC was measured by a proliferation assay. Radiosensitivity and radioenhancement by dFdC of this cell panel and the human ovarian carcinoma cell line A2780 and its dFdC-resistant variant AG6000 were determined by clonogenic assay. Bivariate flowcytometry was performed to study cell cycle changes. Results: In the SWg, a complete deoxycytidine kinase (dCK) deficiency was found on mRNA and protein level. This was accompanied by a 10-fold decrease in dCK activity which resulted in the >1000-fold resistance to dFdC. Sensitivity to other anti-tumor drugs was not altered, except for ara-C (>100-fold resistance). Radiosensitivity was not altered in the dFdC-resistant cell lines SWg and AG6000. High concentrations (50-100 μM dFdC) induced radioenhancement in the dFdC-resistant cell lines similar to the radioenhancement obtained at lower concentrations (10 nM dFdC) in the parental lines. An early S-phase arrest was found in all cell lines after dFdC treatment where radioenhancement was achieved. Conclusions: In the dFdC-resistant lung tumor cell line SWg, the deficiency in dCK is related to the resistance to dFdC and ara-C. No cross-resistance was observed to other anti-tumor drugs used for the treatment in lung cancer. Sensitivity to ionizing radiation was not altered in two different dFdC-resistant cell lines. Resistance to dFdC does not eliminate the ability of dFdC to sensitize cells to radiation

  16. The anti-tumor effect and biological activities of the extract JMM6 ...

    African Journals Online (AJOL)

    Juglans mandshurica Maxim is a traditional herbal medicines in China, and its anti-tumor bioactivities are of research interest. Bioassay-guided fractionation method was employed to isolate anti-tumor compounds from the stem barks of the Juglans mandshurica Maxim. The anti-tumor effect and biological activities of the ...

  17. Polyclonal type II natural killer T cells require PLZF and SAP for their development and contribute to CpG-mediated antitumor response

    Science.gov (United States)

    Zhao, Jie; Weng, Xiufang; Bagchi, Sreya; Wang, Chyung-Ru

    2014-01-01

    CD1d-restricted natural killer T (NKT) cells are innate-like T cells with potent immunomodulatory function via rapid production of both Th1 and Th2 cytokines. NKT cells comprise well-characterized type I NKT cells, which can be detected by α-galactosylceramide-loaded CD1d tetramers, and less-studied type II NKT cells, which do not recognize α-galactosylceramide. Here we characterized type II NKT cells on a polyclonal level by using a Jα18-deficient IL-4 reporter mouse model. This model allows us to track type II NTK cells by the GFP+TCRβ+ phenotype in the thymus and liver. We found type II NKT cells, like type I NKT cells, exhibit an activated phenotype and are dependent on the transcriptional regulator promyelocytic leukemia zinc finger (PLZF) and the adaptor molecule signaling lymphocyte activation molecule-associated protein (SAP) for their development. Type II NKT cells are potently activated by β-D-glucopyranosylceramide (β-GlcCer) but not sulfatide or phospholipids in a CD1d-dependent manner, with the stimulatory capacity of β-GlcCer influenced by acyl chain length. Compared with type I NKT cells, type II NKT cells produce lower levels of IFN-γ but comparable amounts of IL-13 in response to polyclonal T-cell receptor stimulation, suggesting they may play different roles in regulating immune responses. Furthermore, type II NKT cells can be activated by CpG oligodeoxynucletides to produce IFN-γ, but not IL-4 or IL-13. Importantly, CpG-activated type II NKT cells contribute to the antitumor effect of CpG in the B16 melanoma model. Taken together, our data reveal the characteristics of polyclonal type II NKT cells and their potential role in antitumor immunotherapy. PMID:24550295

  18. Synthesis and Biological Evaluation of Novel Furozan-Based Nitric Oxide-Releasing Derivatives of Oridonin as Potential Anti-Tumor Agents

    Directory of Open Access Journals (Sweden)

    Hao Cai

    2012-06-01

    Full Text Available To search for novel nitric oxide (NO releasing anti-tumor agents, a series of novel furoxan/oridonin hybrids were designed and synthesized. Firstly, the nitrate/nitrite levels in the cell lysates were tested by a Griess assay and the results showed that these furoxan-based NO-releasing derivatives could produce high levels of NO in vitro. Then the anti-proliferative activity of these hybrids against four human cancer cell lines was also determined, among which, 9h exhibited the most potential anti-tumor activity with IC50 values of 1.82 µM against K562, 1.81 µM against MGC-803 and 0.86 µM against Bel-7402, respectively. Preliminary structure-activity relationship was concluded based on the experimental data obtained. These results suggested that NO-donor/natural product hybrids may provide a promising approach for the discovery of novel anti-tumor agents.

  19. Mechanisms of resistance to alkylating agents

    OpenAIRE

    Damia, G.; D‘Incalci, M.

    1998-01-01

    Alkylating agents are the most widely used anticancer drugs whose main target is the DNA, although how exactly the DNA lesions cause cell death is still not clear. The emergence of resistance to this class of drugs as well as to other antitumor agents is one of the major causes of failure of cancer treatment. This paper reviews some of the best characterized mechanisms of resistance to alkylating agents. Pre- and post-target mechanisms are recognized, the former able to limit the formation of...

  20. Polymorphisms in the HIV-1 gp41 env gene, natural resistance to enfuvirtide (T-20) and pol resistance among pregnant Brazilian women.

    Science.gov (United States)

    Reis, Mônica Nogueira da Guarda; de Alcântara, Keila Correa; Cardoso, Ludimila Paula Vaz; Stefani, Mariane Martins Araújo

    2014-01-01

    The selective pressure of antiretroviral drugs (ARVs) targeting HIV-1 pol can promote drug resistance mutations in other genomic regions, such as env. Drug resistance among women should be monitored to avoid horizontal and mother-to-child transmission. To describe natural resistance to T-20 (enfuvirtide), gp41 env polymorphisms, mutations in pol and HIV-1 subtypes, 124 pregnant women were recruited. For 98 patients, the gp41 env, protease (PR) and reverse transcriptase (RT) fragments were sequenced. The patients were ARV naïve (n = 30), taking mother-to-child transmission prophylaxis (n = 50), or being treated with highly active ARV therapy/HAART (n = 18). The Stanford and IAS/USA databases and other sources were used to analyze PR/RT, gp41 env resistance mutations. The HIV-1 genetic diversity was analyzed by REGA/phylogenetic analyses. The patients' median age was 25 years (range, 16-42), 18.4% had AIDS. The frequency of natural resistance to T-20 (N42D, L44M, and R46M-low-impact mutations) was 6.1% (6/98); 20.4% (20/98) had compensatory mutations in HR2. The prevalence of transmitted drug resistance in the pol was 13.3% (4/30), and the prevalence of secondary drug resistance was 33.3% (6/18). Two patients were infected with multidrug resistant/MDR viruses. The analysis of HIV-1 subtypes (PR/RT/gp41) revealed that 61.2% (60/98) were subtype B, 12.2% (12/98) were subtype C, 4.1% (4/98) were subtype F1, and 22.4% (22/98) were possible recombinants (BF1 = 20.4%; BC = 2%). Natural resistance to T-20 was not associated with pol resistance or previous ARV use. The high rate of secondary resistance, including MDR, indicates that the number of women that may need T-20 salvage therapy may be higher than anticipated. © 2013 Wiley Periodicals, Inc.

  1. Acquired IFNγ resistance impairs anti-tumor immunity and gives rise to T-cell-resistant melanoma lesions

    Science.gov (United States)

    Sucker, Antje; Zhao, Fang; Pieper, Natalia; Heeke, Christina; Maltaner, Raffaela; Stadtler, Nadine; Real, Birgit; Bielefeld, Nicola; Howe, Sebastian; Weide, Benjamin; Gutzmer, Ralf; Utikal, Jochen; Loquai, Carmen; Gogas, Helen; Klein-Hitpass, Ludger; Zeschnigk, Michael; Westendorf, Astrid M.; Trilling, Mirko; Horn, Susanne; Schilling, Bastian; Schadendorf, Dirk; Griewank, Klaus G.; Paschen, Annette

    2017-01-01

    Melanoma treatment has been revolutionized by antibody-based immunotherapies. IFNγ secretion by CD8+ T cells is critical for therapy efficacy having anti-proliferative and pro-apoptotic effects on tumour cells. Our study demonstrates a genetic evolution of IFNγ resistance in different melanoma patient models. Chromosomal alterations and subsequent inactivating mutations in genes of the IFNγ signalling cascade, most often JAK1 or JAK2, protect melanoma cells from anti-tumour IFNγ activity. JAK1/2 mutants further evolve into T-cell-resistant HLA class I-negative lesions with genes involved in antigen presentation silenced and no longer inducible by IFNγ. Allelic JAK1/2 losses predisposing to IFNγ resistance development are frequent in melanoma. Subclones harbouring inactivating mutations emerge under various immunotherapies but are also detectable in pre-treatment biopsies. Our data demonstrate that JAK1/2 deficiency protects melanoma from anti-tumour IFNγ activity and results in T-cell-resistant HLA class I-negative lesions. Screening for mechanisms of IFNγ resistance should be considered in therapeutic decision-making. PMID:28561041

  2. Flavonoids Isolated From the Flowers of Limonium bicolor and their In vitro Antitumor Evaluation.

    Science.gov (United States)

    Chen, Jian; Teng, Jiehui; Ma, Li; Tong, Haiying; Ren, Bingru; Wang, Linshan; Li, Weilin

    2017-01-01

    Limonium bicolor , a halophytic species, can grow in saline or saline-alkali soil, is well known as a traditional Chinese medicine. Recently it attracted much attention for its treatment for cancer. The present study was performed to evaluate this species from the phytochemical standpoint and the possible relationship between the antitumor activity and its natural products. The chemical constituents from the flowers of L. bicolor were investigated through bioassay-guided fractionation and isolation. All the individual compounds were characterized by spectroscopic analysis and their potential antitumor activity was tested against three different human tumor cell lines by MTT assays. The EtOAc extract was proven as the most potent fraction and further fractionation led to the isolation of 15 natural flavonoids, which were characterized as luteolin (1), acacetin (2), quercetin (3), isorhamnetin (4), kaempferol (5), eriodictyol (6), kaempferol-3-O-α-L-rhamnoside (7), kaempferol-3-O-β-D-glucoside (8), quercetin-3-O-α-L-rhamnoside (9), quercetin-3-O-β-D-glucoside (10), quercetin-3-O-β-D-galactoside (11), myricetin-3-O-α-L-rhamnoside (12), kaempferol-3-O-(6″-O-galloyl)-β-D-glucoside (13), hesperidin (14) and rutin (15). The biotesting results demonstrated that both compounds 1 and 3 showed good cytotoxicity against human colon cancer cells (LOVO). Compound 5 exhibited relative greater growth inhibition against both human breast cancer cells (MCF-7) and osteosarcoma cell lines (U2-OS) at the concentration of 100 μg/mL. On the basis of these findings, the flavonoids were deduced to be potentially responsible for the antitumor activity of L. bicolor . The preliminary structure-activity relationship analysis suggests that the 3-O-glycosylation moiety in natural flavonoids was not essential for the antiproliferative activity on LOVO and U2-OS cells. The phytochemical investigation of Limonium bicolor led to the isolation of 15 flavonoids.The biotesting of the

  3. Potential mechanisms of resistance to microtubule inhibitors.

    Science.gov (United States)

    Kavallaris, Maria; Annereau, Jean-Philippe; Barret, Jean-Marc

    2008-06-01

    Antimitotic drugs targeting the microtubules, such as the taxanes and vinca alkaloids, are widely used in the treatment of neoplastic diseases. Development of drug resistance over time, however, limits the efficacy of these agents and poses a clinical challenge to long-term improvement of patient outcomes. Understanding the mechanism(s) of drug resistance becomes paramount to allowing for alternative, if not improved, therapeutic options that might circumvent this challenge. Vinflunine, a novel microtubule inhibitor, has shown superior preclinical antitumor activity, and displays a different pattern of resistance, compared with other agents in the vinca alkaloid class.

  4. Interplay between Natural Killer Cells and Anti-HER2 Antibodies: Perspectives for Breast Cancer Immunotherapy

    Directory of Open Access Journals (Sweden)

    Aura Muntasell

    2017-11-01

    Full Text Available Overexpression of the human epidermal growth factor receptor 2 (HER2 defines a subgroup of breast tumors with aggressive behavior. The addition of HER2-targeted antibodies (i.e., trastuzumab, pertuzumab to chemotherapy significantly improves relapse-free and overall survival in patients with early-stage and advanced disease. Nonetheless, considerable proportions of patients develop resistance to treatment, highlighting the need for additional and co-adjuvant therapeutic strategies. HER2-specific antibodies can trigger natural killer (NK cell-mediated antibody-dependent cellular cytotoxicity and indirectly enhance the development of tumor-specific T cell immunity; both mechanisms contributing to their antitumor efficacy in preclinical models. Antibody-dependent NK cell activation results in the release of cytotoxic granules as well as the secretion of pro-inflammatory cytokines (i.e., IFNγ and TNFα and chemokines. Hence, NK cell tumor suppressive functions include direct cytolytic killing of tumor cells as well as the regulation of subsequent antitumor adaptive immunity. Albeit tumors with gene expression signatures associated to the presence of cytotoxic lymphocyte infiltrates benefit from trastuzumab-based treatment, NK cell-related biomarkers of response/resistance to HER2-specific therapeutic antibodies in breast cancer patients remain elusive. Several variables, including (i the configuration of the patient NK cell repertoire; (ii tumor molecular features (i.e., estrogen receptor expression; (iii concomitant therapeutic regimens (i.e., chemotherapeutic agents, tyrosine kinase inhibitors; and (iv evasion mechanisms developed by progressive breast tumors, have been shown to quantitatively and qualitatively influence antibody-triggered NK cell responses. In this review, we discuss possible interventions for restoring/enhancing the therapeutic activity of HER2 therapeutic antibodies by harnessing NK cell antitumor potential through

  5. Environmental and Sustainable Technology Evaluation: Mold-resistant Lonseal flooring--Lonseal, Inc., Lonwood Natural

    Science.gov (United States)

    The test program measured the mold resistance of Lonseal Lonwood Natural flooring. One additional ancillary test for emissions of VOCs and formaldehyde was performed. Lonwood Natural flooring is a sheet vinyl product with an embossed wood-grain texture. Constructed in multiple la...

  6. Reduced pyrazinamidase activity and the natural resistance of Mycobacterium kansasii to the antituberculosis drug pyrazinamide.

    Science.gov (United States)

    Sun, Z; Zhang, Y

    1999-03-01

    Pyrazinamide (PZA), an analog of nicotinamide, is a prodrug that requires conversion to the bactericidal compound pyrazinoic acid (POA) by the bacterial pyrazinamidase (PZase) activity of nicotinamidase to show activity against Mycobacterium tuberculosis. Mutations leading to a loss of PZase activity cause PZA resistance in M. tuberculosis. M. kansasii is naturally resistant to PZA and has reduced PZase activity along with an apparently detectable nicotinamidase activity. The role of the reduction in PZase activity in the natural PZA resistance of M. kansasii is unknown. The MICs of PZA and POA for M. kansasii were determined to be 500 and 125 micrograms/ml, respectively. Using [14C]PZA and [14C]nicotinamide, we found that M. kansasii had about 5-fold-less PZase activity and about 25-fold-less nicotinamidase activity than M. tuberculosis. The M. kansasii pncA gene was cloned on a 1.8-kb BamHI DNA fragment, using M. avium pncA probe. Sequence analysis showed that the M. kansasii pncA gene encoded a protein with homology to its counterparts from M. tuberculosis (69.9%), M. avium (65.6%), and Escherichia coli (28.5%). Transformation of naturally PZA-resistant M. bovis BCG with M. kansasii pncA conferred partial PZA susceptibility. Transformation of M. kansasii with M. avium pncA caused functional expression of PZase and high-level susceptibility to PZA, indicating that the natural PZA resistance in M. kansasii results from a reduced PZase activity. Like M. tuberculosis, M. kansasii accumulated POA in the cells at an acidic pH; however, due to its highly active POA efflux pump, the naturally PZA-resistant species M. smegmatis did not. These findings suggest the existence of a weak POA efflux mechanism in M. kansasii.

  7. Tivantinib (ARQ-197) exhibits anti-tumor activity with down-regulation of FAK in oral squamous cell carcinoma

    International Nuclear Information System (INIS)

    Xi, Wei-Hong; Yang, Li-Yun; Cao, Zhong-Yi; Qian, Yong

    2015-01-01

    Oral squamous cell carcinoma (OSCC) is one of the most common cancers worldwide and the 5 years survival rate of the patients is about 60% in the USA, due to acquired chemotherapeutic resistance and metastasis of the disease. In this study, we found that tivantinib, a selective MET inhibitor, suppresses OCSS cell proliferation and colony formation, however, anti-tumor activities induced by tivantinib are independent of the inhibition of MET signaling pathway. In addition, tivantinib cause G2/M cell cycle arrest and caspases-dependent apoptosis in OSCC cell lines. We also found that tivantinib dose-dependently suppressed the activation and expression of FAK. In all, these data suggested that tivantinib may be developed as a chemotherapeutic agent to effectively treat certain cancers including OSCC. - Highlights: • Tivantinib suppresses OSCC cell growth independent of the inhibition of HGF/MET signaling pathway. • Tivantinib blocks cell cycle and induces caspases-mediated apoptosis. • Tivantinib elicits its anti-tumor activity with the inhibition of FAK signaling pathway

  8. Tivantinib (ARQ-197) exhibits anti-tumor activity with down-regulation of FAK in oral squamous cell carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Xi, Wei-Hong [Department of Oral and Maxillofacial Surgery, First Affiliated Hospital, Nanchang University, Nanchang 330006 (China); Yang, Li-Yun [Department of Blood Transfusion, First Affiliated Hospital, Nanchang University, Nanchang 330006 (China); Cao, Zhong-Yi, E-mail: m18070383032@163.com [Department of Oral and Maxillofacial Surgery, First Affiliated Hospital, Nanchang University, Nanchang 330006 (China); Qian, Yong, E-mail: yfykqkqy@163.com [Department of Oral and Maxillofacial Surgery, First Affiliated Hospital, Nanchang University, Nanchang 330006 (China)

    2015-02-20

    Oral squamous cell carcinoma (OSCC) is one of the most common cancers worldwide and the 5 years survival rate of the patients is about 60% in the USA, due to acquired chemotherapeutic resistance and metastasis of the disease. In this study, we found that tivantinib, a selective MET inhibitor, suppresses OCSS cell proliferation and colony formation, however, anti-tumor activities induced by tivantinib are independent of the inhibition of MET signaling pathway. In addition, tivantinib cause G2/M cell cycle arrest and caspases-dependent apoptosis in OSCC cell lines. We also found that tivantinib dose-dependently suppressed the activation and expression of FAK. In all, these data suggested that tivantinib may be developed as a chemotherapeutic agent to effectively treat certain cancers including OSCC. - Highlights: • Tivantinib suppresses OSCC cell growth independent of the inhibition of HGF/MET signaling pathway. • Tivantinib blocks cell cycle and induces caspases-mediated apoptosis. • Tivantinib elicits its anti-tumor activity with the inhibition of FAK signaling pathway.

  9. Marine Natural Products as Models to Circumvent Multidrug Resistance

    Directory of Open Access Journals (Sweden)

    Solida Long

    2016-07-01

    Full Text Available Multidrug resistance (MDR to anticancer drugs is a serious health problem that in many cases leads to cancer treatment failure. The ATP binding cassette (ABC transporter P-glycoprotein (P-gp, which leads to premature efflux of drugs from cancer cells, is often responsible for MDR. On the other hand, a strategy to search for modulators from natural products to overcome MDR had been in place during the last decades. However, Nature limits the amount of some natural products, which has led to the development of synthetic strategies to increase their availability. This review summarizes the research findings on marine natural products and derivatives, mainly alkaloids, polyoxygenated sterols, polyketides, terpenoids, diketopiperazines, and peptides, with P-gp inhibitory activity highlighting the established structure-activity relationships. The synthetic pathways for the total synthesis of the most promising members and analogs are also presented. It is expected that the data gathered during the last decades concerning their synthesis and MDR-inhibiting activities will help medicinal chemists develop potential drug candidates using marine natural products as models which can deliver new ABC transporter inhibitor scaffolds.

  10. The hTERT promoter enhances the antitumor activity of an oncolytic adenovirus under a hypoxic microenvironment.

    Directory of Open Access Journals (Sweden)

    Yuuri Hashimoto

    Full Text Available Hypoxia is a microenvironmental factor that contributes to the invasion, progression and metastasis of tumor cells. Hypoxic tumor cells often show more resistance to conventional chemoradiotherapy than normoxic tumor cells, suggesting the requirement of novel antitumor therapies to efficiently eliminate the hypoxic tumor cells. We previously generated a tumor-specific replication-competent oncolytic adenovirus (OBP-301: Telomelysin, in which the human telomerase reverse transcriptase (hTERT promoter drives viral E1 expression. Since the promoter activity of the hTERT gene has been shown to be upregulated by hypoxia, we hypothesized that, under hypoxic conditions, the antitumor effect of OBP-301 with the hTERT promoter would be more efficient than that of the wild-type adenovirus 5 (Ad5. In this study, we investigated the antitumor effects of OBP-301 and Ad5 against human cancer cells under a normoxic (20% oxygen or a hypoxic (1% oxygen condition. Hypoxic condition induced nuclear accumulation of the hypoxia-inducible factor-1α and upregulation of hTERT promoter activity in human cancer cells. The cytopathic activity of OBP-301 was significantly higher than that of Ad5 under hypoxic condition. Consistent with their cytopathic activity, the replication of OBP-301 was significantly higher than that of Ad5 under the hypoxic condition. OBP-301-mediated E1A was expressed within hypoxic areas of human xenograft tumors in mice. These results suggest that the cytopathic activity of OBP-301 against hypoxic tumor cells is mediated through hypoxia-mediated activation of the hTERT promoter. Regulation of oncolytic adenoviruses by the hTERT promoter is a promising antitumor strategy, not only for induction of tumor-specific oncolysis, but also for efficient elimination of hypoxic tumor cells.

  11. Anti-tumor effect of polysaccharides from rhizome of Curculigo ...

    African Journals Online (AJOL)

    The anti-tumor effect of PDC on cervical cancer was investigated in vivo in mice injected with Hela cells. The parameters measured were tumor volume and weight. In vitro anti-tumor effects of PDC were assessed by measuring expressions of caspase-3, caspase-9 and P53 proteins in Hela cells via ELISA assay. Thymus ...

  12. Anti-tumor and anti-angiogenic ergosterols from Ganoderma lucidum

    Science.gov (United States)

    Chen, Shaodan; Yong, Tianqiao; Zhang, Yifang; Su, Jiyan; Jiao, Chunwei; Xie, Yizhen

    2017-10-01

    This study was carried out to isolate chemical constituents from the lipid enriched fraction of Ganoderma lucidum extract and to evaluate their anti-proliferative effect on cancer cell lines and human umbilical vein endothelial cells. Ergosterol derivatives (1-14) were isolated from the lipid enriched fraction of G. lucidum. Their structures were established on the basis of spectroscopic analyses or by comparison of mass and NMR spectral data with those reported previously. Amongst, compound 1 was isolated and identified as a new compound. All the compounds were evaluated for their inhibitory effect on tumor cells and human umbilical vein endothelial cells in vitro. Compounds 9-13 displayed inhibitory activity against two tumor cell lines and human umbilical vein endothelial cells, which indicated that these four compounds had both anti-tumor and anti-angiogenesis activities. Compound 2 had significant selective inhibition against two tumor cell lines, while 3 exhibited selective inhibition against human umbilical vein endothelial cells. The structure–activity relationships for inhibiting human HepG2 cells were revealed by 3D-QASR. Ergosterol content in different parts of the raw material and products of G. lucidum was quantified. This study provides a basis for further development and utilization of ergosterol derivatives as natural nutraceuticals and functional food ingredients, or as source of new potential antitumor or anti-angiogenesis chemotherapy agent.

  13. Antitumor and Immunomodulatory Effects of Polysaccharides from Broken-Spore of Ganoderma lucidum

    Directory of Open Access Journals (Sweden)

    Peng-Yun eWang

    2012-07-01

    Full Text Available The antitumor activity of Gl-BSP, a polysaccharide isolated from boiling water extract of the broken-spores of Ganoderma lucidum (Leyss ex Fr Karst. and its possible mechanism were investigated in vivo and in vitro. It was showed that Gl-BSP (50, 100, 200 mg/kg exhibited antitumor effect against Sarcoma 180 (S180 in BALB/c mice. The Gl-BSP was not cytotoxicity in S180 cells and PG cells (human lung carcinoma cell in vitro. However, Gl-BSP-treated serum potently inhibited S180 cells and PG cells proliferation in vitro. Moreover, Gl-BSP could promote the splenic lymphocyte proliferation induced by Con A or LPS, enhance nature killer cell (NK cell cytotoxic activity, augment the percentage of neutral red (NR phagocytosis by macrophages, and increase the percentage of the CD4+ or CD8+ subset in S180-bearing BALB/c mice. The level of IFN-γ, TNF-α and NO of serum apparently was increased by Gl-BSP. Gl-BSP also showed immunomodulatory activities in tumor-bearing mice. Furthermore,It was proved that neutralization with anti-TNF-α and/or anti-IFN-γ significantly diminished growth inhibition induced by Gl-BSP –treated serum in S180 or PG cells. Blocking effect was noted in the combination of anti-TNF-α and anti-IFN-γ. These observations suggest that the antitumor activity of Gl-BSP may mainly relate to the activation of the immune response of the host organism by the stimulation of NK cells, T cells, and macrophages.

  14. Molecular mechanisms of drug resistance in natural Leishmania populations vary with genetic background.

    Directory of Open Access Journals (Sweden)

    Saskia Decuypere

    Full Text Available The evolution of drug-resistance in pathogens is a major global health threat. Elucidating the molecular basis of pathogen drug-resistance has been the focus of many studies but rarely is it known whether a drug-resistance mechanism identified is universal for the studied pathogen; it has seldom been clarified whether drug-resistance mechanisms vary with the pathogen's genotype. Nevertheless this is of critical importance in gaining an understanding of the complexity of this global threat and in underpinning epidemiological surveillance of pathogen drug resistance in the field. This study aimed to assess the molecular and phenotypic heterogeneity that emerges in natural parasite populations under drug treatment pressure. We studied lines of the protozoan parasite Leishmania (L. donovani with differential susceptibility to antimonial drugs; the lines being derived from clinical isolates belonging to two distinct genetic populations that circulate in the leishmaniasis endemic region of Nepal. Parasite pathways known to be affected by antimonial drugs were characterised on five experimental levels in the lines of the two populations. Characterisation of DNA sequence, gene expression, protein expression and thiol levels revealed a number of molecular features that mark antimonial-resistant parasites in only one of the two populations studied. A final series of in vitro stress phenotyping experiments confirmed this heterogeneity amongst drug-resistant parasites from the two populations. These data provide evidence that the molecular changes associated with antimonial-resistance in natural Leishmania populations depend on the genetic background of the Leishmania population, which has resulted in a divergent set of resistance markers in the Leishmania populations. This heterogeneity of parasite adaptations provides severe challenges for the control of drug resistance in the field and the design of molecular surveillance tools for widespread

  15. Evaluation of cytotoxic and antitumoral properties of Tessaria absinthioides (Hook & Arn DC, "pájaro bobo", aqueous extract

    Directory of Open Access Journals (Sweden)

    Fabio A. Persia

    2017-08-01

    Full Text Available Higher plants have provided various natural derived drugs used currently in western medicine. Tessaria absinthioides (Hook. & Arn. DC, Asteraceae, is a native plant from South-America with reported ethnopharmacological and culinary uses. Despite recent scientific reports about plants properties, there is not a well conducted research about its anticancer and potential toxic effects. The current work demonstrates the plant aqueous extract composition; the in vitro induced cytotoxicity, and explores, in vivo, its oral toxicity and antitumoral effects. Composition of aqueous extract was determined by phytochemical reactions. Cytotoxicity was tested in tumoral (Hela, Gli-37, HCT-116 and MCF-7 and non-tumoral (HBL-100 cells, using MTT assay. Oral toxicity and the antitumor activity against colorectal carcinoma were studied in rodents. The chemical analysis revealed the presence of flavonoids, carbohydrates, sterols, terpenes and tannins. Cytotoxicity towards tumoral cells was observed (CV50: 3.0 to 14.8 ug/ml; while in non-tumoral cells, extracts evidenced a selective reduced toxicity (CV50: 29.5 ug/ml. Oral administration of the extract does not induce acute nor dose-repeated toxicity at doses up to 2000 mg/kg and 1000 mg/kg/day, respectively. The antitumoral effect was confirmed by a significant increase in a median survival from 24 weeks (non-treated to 30 weeks (T. absinthioides treated. The present data indicate that T. absinthioides extract exhibits cytotoxicity against cancer cell lines, with no-toxic effects and significant antitumoral effects in colorectal cancer when is orally administrated. In conclusion, T. absinthioides possesses selective cytotoxicity and antitumoral activities, making its plant derivatives products promising for cancer research and treatment.

  16. A QSAR approach for virtual screening of lead-like molecules en route to antitumor and antibiotic drugs from marine and microbial natural products

    Directory of Open Access Journals (Sweden)

    Florbela Pereira

    2014-05-01

    Figure 1. The unreported 15 lead antibiotic MNPs and MbNPs from AntiMarin database, using the best Rfs antibiotic model with a probability of being antibiotic greater than or equal to 0.8. Figure 2. The selected 4 lead antitumor MNPs and MbNPs from the AntiMarin database, using the best Rfs antitumor model with a probability of being antitumor greater than or equal to 0.8. The present work corroborates by one side the results of our previous work6 and enables the presentation of a new set of possible lead like bioactive compounds. Additionally, it is shown the usefulness of quantum-chemical descriptors in the discrimination of biological active and inactive compounds. The use of the εHOMO quantum-chemical descriptor in the discrimination of large scale data sets of lead-like or drug-like compounds has never been reported. This approach results in the reduction, in great extent, of the number of compounds used in real screens, and it reinforces the results of our previous work. Furthermore, besides the virtual screening, the computational methods can be very useful to build appropriate databases, allowing for effective shortcuts of NP extracts dereplication procedures, which will certainly result in increasing the efficiency of drug discovery.

  17. Antitumor effect of malaria parasite infection in a murine Lewis lung cancer model through induction of innate and adaptive immunity.

    Science.gov (United States)

    Chen, Lili; He, Zhengxiang; Qin, Li; Li, Qinyan; Shi, Xibao; Zhao, Siting; Chen, Ling; Zhong, Nanshan; Chen, Xiaoping

    2011-01-01

    Lung cancer is the most common malignancy in humans and its high fatality means that no effective treatment is available. Developing new therapeutic strategies for lung cancer is urgently needed. Malaria has been reported to stimulate host immune responses, which are believed to be efficacious for combating some clinical cancers. This study is aimed to provide evidence that malaria parasite infection is therapeutic for lung cancer. Antitumor effect of malaria infection was examined in both subcutaneously and intravenously implanted murine Lewis lung cancer (LLC) model. The results showed that malaria infection inhibited LLC growth and metastasis and prolonged the survival of tumor-bearing mice. Histological analysis of tumors from mice infected with malaria revealed that angiogenesis was inhibited, which correlated with increased terminal deoxynucleotidyl transferase-mediated (TUNEL) staining and decreased Ki-67 expression in tumors. Through natural killer (NK) cell cytotoxicity activity, cytokine assays, enzyme-linked immunospot assay, lymphocyte proliferation, and flow cytometry, we demonstrated that malaria infection provided anti-tumor effects by inducing both a potent anti-tumor innate immune response, including the secretion of IFN-γ and TNF-α and the activation of NK cells as well as adaptive anti-tumor immunity with increasing tumor-specific T-cell proliferation and cytolytic activity of CD8(+) T cells. Notably, tumor-bearing mice infected with the parasite developed long-lasting and effective tumor-specific immunity. Consequently, we found that malaria parasite infection could enhance the immune response of lung cancer DNA vaccine pcDNA3.1-hMUC1 and the combination produced a synergistic antitumor effect. Malaria infection significantly suppresses LLC growth via induction of innate and adaptive antitumor responses in a mouse model. These data suggest that the malaria parasite may provide a novel strategy or therapeutic vaccine vector for anti-lung cancer

  18. Antitumor effect of malaria parasite infection in a murine Lewis lung cancer model through induction of innate and adaptive immunity.

    Directory of Open Access Journals (Sweden)

    Lili Chen

    Full Text Available BACKGROUND: Lung cancer is the most common malignancy in humans and its high fatality means that no effective treatment is available. Developing new therapeutic strategies for lung cancer is urgently needed. Malaria has been reported to stimulate host immune responses, which are believed to be efficacious for combating some clinical cancers. This study is aimed to provide evidence that malaria parasite infection is therapeutic for lung cancer. METHODOLOGY/PRINCIPAL FINDINGS: Antitumor effect of malaria infection was examined in both subcutaneously and intravenously implanted murine Lewis lung cancer (LLC model. The results showed that malaria infection inhibited LLC growth and metastasis and prolonged the survival of tumor-bearing mice. Histological analysis of tumors from mice infected with malaria revealed that angiogenesis was inhibited, which correlated with increased terminal deoxynucleotidyl transferase-mediated (TUNEL staining and decreased Ki-67 expression in tumors. Through natural killer (NK cell cytotoxicity activity, cytokine assays, enzyme-linked immunospot assay, lymphocyte proliferation, and flow cytometry, we demonstrated that malaria infection provided anti-tumor effects by inducing both a potent anti-tumor innate immune response, including the secretion of IFN-γ and TNF-α and the activation of NK cells as well as adaptive anti-tumor immunity with increasing tumor-specific T-cell proliferation and cytolytic activity of CD8(+ T cells. Notably, tumor-bearing mice infected with the parasite developed long-lasting and effective tumor-specific immunity. Consequently, we found that malaria parasite infection could enhance the immune response of lung cancer DNA vaccine pcDNA3.1-hMUC1 and the combination produced a synergistic antitumor effect. CONCLUSIONS/SIGNIFICANCE: Malaria infection significantly suppresses LLC growth via induction of innate and adaptive antitumor responses in a mouse model. These data suggest that the malaria

  19. In vitro and in vivo antitumor activity of crude extracts obtained from Brazilian Chromobacterium sp isolates

    Energy Technology Data Exchange (ETDEWEB)

    Menezes, C.B.A.; Silva, B.P. [Universidade Estadual de Campinas, Centro Pluridisciplinar de Pesquisas Químicas, Biológicas e Agrícolas, Campinas, SP (Brazil); Universidade de São Paulo, Interunidades em Biotecnologia, São Paulo, SP (Brazil); Sousa, I.M.O.; Ruiz, A.L.T.G.; Spindola, H.M. [Universidade Estadual de Campinas, Centro Pluridisciplinar de Pesquisas Químicas, Biológicas e Agrícolas, Campinas, SP (Brazil); Cabral, E.; Eberlin, M.N. [Instituto de Química, Universidade Estadual de Campinas, Laboratório Thomson Mass Spectrometry, Campinas, SP (Brazil); Tinti, S.V.; Carvalho, J.E. [Universidade Estadual de Campinas, Centro Pluridisciplinar de Pesquisas Químicas, Biológicas e Agrícolas, Campinas, SP (Brazil); Foglio, M.A.; Fantinatti-Garboggini, F. [Universidade Estadual de Campinas, Centro Pluridisciplinar de Pesquisas Químicas, Biológicas e Agrícolas, Campinas, SP (Brazil); Universidade de São Paulo, Interunidades em Biotecnologia, São Paulo, SP (Brazil)

    2012-10-23

    Natural products produced by microorganisms have been an important source of new substances and lead compounds for the pharmaceutical industry. Chromobacterium violaceum is a Gram-negative β-proteobacterium, abundant in water and soil in tropical and subtropical regions and it produces violacein, a pigment that has shown great pharmaceutical potential. Crude extracts of five Brazilian isolates of Chromobacterium sp (0.25, 2.5, 25, and 250 µg/mL) were evaluated in an in vitro antitumor activity assay with nine human tumor cells. Secondary metabolic profiles were analyzed by liquid chromatography and electrospray ionization mass spectrometry resulting in the identification of violacein in all extracts, whereas FK228 was detected only in EtCE 308 and EtCE 592 extracts. AcCE and EtCE 310 extracts showed selectivity for NCI/ADR-RES cells in the in vitro assay and were evaluated in vivo in the solid Ehrlich tumor model, resulting in 50.3 and 54.6% growth inhibition, respectively. The crude extracts of Chromobacterium sp isolates showed potential and selective antitumor activities for certain human tumor cells, making them a potential source of lead compounds. Furthermore, the results suggest that other compounds, in addition to violacein, deoxyviolacein and FK228, may be involved in the antitumor effect observed.

  20. In vitro and in vivo antitumor activity of crude extracts obtained from Brazilian Chromobacterium sp isolates

    Directory of Open Access Journals (Sweden)

    C.B.A. Menezes

    2013-01-01

    Full Text Available Natural products produced by microorganisms have been an important source of new substances and lead compounds for the pharmaceutical industry. Chromobacterium violaceum is a Gram-negative β-proteobacterium, abundant in water and soil in tropical and subtropical regions and it produces violacein, a pigment that has shown great pharmaceutical potential. Crude extracts of five Brazilian isolates of Chromobacterium sp (0.25, 2.5, 25, and 250 µg/mL were evaluated in an in vitro antitumor activity assay with nine human tumor cells. Secondary metabolic profiles were analyzed by liquid chromatography and electrospray ionization mass spectrometry resulting in the identification of violacein in all extracts, whereas FK228 was detected only in EtCE 308 and EtCE 592 extracts. AcCE and EtCE 310 extracts showed selectivity for NCI/ADR-RES cells in the in vitro assay and were evaluated in vivo in the solid Ehrlich tumor model, resulting in 50.3 and 54.6% growth inhibition, respectively. The crude extracts of Chromobacterium sp isolates showed potential and selective antitumor activities for certain human tumor cells, making them a potential source of lead compounds. Furthermore, the results suggest that other compounds, in addition to violacein, deoxyviolacein and FK228, may be involved in the antitumor effect observed.

  1. In vitro and in vivo antitumor activity of crude extracts obtained from Brazilian Chromobacterium sp isolates

    International Nuclear Information System (INIS)

    Menezes, C.B.A.; Silva, B.P.; Sousa, I.M.O.; Ruiz, A.L.T.G.; Spindola, H.M.; Cabral, E.; Eberlin, M.N.; Tinti, S.V.; Carvalho, J.E.; Foglio, M.A.; Fantinatti-Garboggini, F.

    2012-01-01

    Natural products produced by microorganisms have been an important source of new substances and lead compounds for the pharmaceutical industry. Chromobacterium violaceum is a Gram-negative β-proteobacterium, abundant in water and soil in tropical and subtropical regions and it produces violacein, a pigment that has shown great pharmaceutical potential. Crude extracts of five Brazilian isolates of Chromobacterium sp (0.25, 2.5, 25, and 250 µg/mL) were evaluated in an in vitro antitumor activity assay with nine human tumor cells. Secondary metabolic profiles were analyzed by liquid chromatography and electrospray ionization mass spectrometry resulting in the identification of violacein in all extracts, whereas FK228 was detected only in EtCE 308 and EtCE 592 extracts. AcCE and EtCE 310 extracts showed selectivity for NCI/ADR-RES cells in the in vitro assay and were evaluated in vivo in the solid Ehrlich tumor model, resulting in 50.3 and 54.6% growth inhibition, respectively. The crude extracts of Chromobacterium sp isolates showed potential and selective antitumor activities for certain human tumor cells, making them a potential source of lead compounds. Furthermore, the results suggest that other compounds, in addition to violacein, deoxyviolacein and FK228, may be involved in the antitumor effect observed

  2. Aldo-keto reductase and alcohol dehydrogenase contribute to benznidazole natural resistance in Trypanosoma cruzi.

    Science.gov (United States)

    González, Laura; García-Huertas, Paola; Triana-Chávez, Omar; García, Gabriela Andrea; Murta, Silvane Maria Fonseca; Mejía-Jaramillo, Ana M

    2017-12-01

    The improvement of Chagas disease treatment is focused not only on the development of new drugs but also in understanding mechanisms of action and resistance to drugs conventionally used. Thus, some strategies aim to detect specific changes in proteins between sensitive and resistant parasites and to evaluate the role played in these processes by functional genomics. In this work, we used a natural Trypanosoma cruzi population resistant to benznidazole, which has clones with different susceptibilities to this drug without alterations in the NTR I gene. Using 2DE-gel electrophoresis, the aldo-keto reductase and the alcohol dehydrogenase proteins were found up regulated in the natural resistant clone and therefore their possible role in the resistance to benznidazole and glyoxal was investigated. Both genes were overexpressed in a drug sensitive T. cruzi clone and the biological changes in response to these compounds were evaluated. The results showed that the overexpression of these proteins enhances resistance to benznidazole and glyoxal in T. cruzi. Moreover, a decrease in mitochondrial and cell membrane damage was observed, accompanied by a drop in the intracellular concentration of reactive oxygen species after treatment. Our results suggest that these proteins are involved in the mechanism of action of benznidazole. © 2017 John Wiley & Sons Ltd.

  3. Effects of extractives and ash on natural resistance of four woods to xylophogous termites

    Directory of Open Access Journals (Sweden)

    Juarez Benigno Paes

    2013-09-01

    Full Text Available This study tested the natural resistance of wood of four tree species to Nasutitermes corniger Motsch. xylophogous termite attack and correlate the resistance with the amount of extract and ash in the chemical composition of the tested species. The species evaluated were Anadenanthera colubrina (Vell. Brenan. var. cebil (Gris. Alts., Tabebuia aurea (Mart. Bureau., Amburana cearensis (Allem. A.C.Sm. and Eucalyptus camaldulensis Dehnh. Test samples with dimensions of 2.00 x 10.16 x 0.64 cm (radial x longitudinal x tangential were obtained at two positions (external heartwood and sapwood of each species. The samples were exposed to action of termites for 45 days in food preference assay. The content of wood extractives was obtained through the sawdust that went through sieve of 40 mesh and were retained in the 60 mesh. The natural resistance was not associated with wood extractive contents. The wood more resistant to termite attack was the Anadenanthera colubrina var. cebil in the two positions (external heartwood and sapwood and Eucalyptus camaldulensis wood presented the greatest wear. The biological resistance of wood was correlated with ash content, i.e., the species with the highest levels was the most resistant to termite attack.

  4. Synthesis, Characterization and in Vitro Antitumor Activity of Platinum(II Oxalato Complexes Involving 7-Azaindole Derivatives as Coligands

    Directory of Open Access Journals (Sweden)

    Pavel Štarha

    2014-07-01

    Full Text Available The platinum(II oxalato complexes [Pt(ox(naza2] (1–3 were synthesized and characterized by elemental analysis (C, H, N, multinuclear NMR spectroscopy (1H, 13C, 15N, 195Pt and electrospray ionization mass spectrometry (ESI-MS; naza = 4-chloro-7-azaindole (4Claza; 1, 3-bromo-7-azaindole (3Braza; 2 or 4-bromo-7-azaindole (4Braza; 3. The prepared substances were screened for their in vitro antitumor activity on the osteosarcoma (HOS and breast adenocarcinoma (MCF7 human cancer cell lines, where 2 showed moderate antitumor effect (IC50 = 27.5 μM, and 18.3 μM, respectively. The complex 2 was further tested on a panel of six others human cancer cell lines, including the malignant melanoma (G361, cervix carcinoma (HeLa, ovarian carcinoma (A2780, cisplatin-resistant ovarian carcinoma (A2780R, lung carcinoma (A549 and prostate adenocarcinoma (LNCaP. This substance was found to be moderate antitumor effective against G361 (IC50 = 17.3 μM, HeLa (IC50 = 31.8 μM and A2780 (IC50 = 19.2 μM cell lines. The complex 2 was also studied by NMR for its solution stability and by ESI-MS experiments for its ability to interact with biomolecules, such as cysteine, glutathione or guanosine 5'-monophosphate.

  5. Expression of microRNA-15b and the glycosyltransferase GCNT3 correlates with antitumor efficacy of Rosemary diterpenes in colon and pancreatic cancer.

    Directory of Open Access Journals (Sweden)

    Margarita González-Vallinas

    Full Text Available Colorectal and pancreatic cancers remain important contributors to cancer mortality burden and, therefore, new therapeutic approaches are urgently needed. Rosemary (Rosmarinus officinalis L. extracts and its components have been reported as natural potent antiproliferative agents against cancer cells. However, to potentially apply rosemary as a complementary approach for cancer therapy, additional information regarding the most effective composition, its antitumor effect in vivo and its main molecular mediators is still needed. In this work, five carnosic acid-rich supercritical rosemary extracts with different chemical compositions have been assayed for their antitumor activity both in vivo (in nude mice and in vitro against colon and pancreatic cancer cells. We found that the antitumor effect of carnosic acid together with carnosol was higher than the sum of their effects separately, which supports the use of the rosemary extract as a whole. In addition, gene and microRNA expression analyses have been performed to ascertain its antitumor mechanism, revealing that up-regulation of the metabolic-related gene GCNT3 and down-regulation of its potential epigenetic modulator miR-15b correlate with the antitumor effect of rosemary. Moreover, plasmatic miR-15b down-regulation was detected after in vivo treatment with rosemary. Our results support the use of carnosic acid-rich rosemary extract as a complementary approach in colon and pancreatic cancer and indicate that GCNT3 expression may be involved in its antitumor mechanism and that miR-15b might be used as a non-invasive biomarker to monitor rosemary anticancer effect.

  6. Vaccination with OK-432 followed by TC-1 tumor lysate leads to significant antitumor effects.

    Science.gov (United States)

    Chen, I-Ju; Yen, Chih-Feng; Lin, Kun-Ju; Lee, Chyi-Long; Soong, Yung-Kuei; Lai, Chyong-Huey; Lin, Cheng-Tao

    2011-07-01

    Human papillomavirus (HPV) infects large numbers of women worldwide and is present in more than 99% of all cervical cancer. TC-1 cell is a cell line with high expression of E7 antigen of HPV type 16 and its cell lysate has been demonstrated as an ideal inducer of E7-specific, antitumor immunity. OK-432 (Picibanil), a penicillin-killed Streptococcus pyogenes, has been reported with potent immunomodulation properties in cancer treatment by stimulating the maturation of dendritic cells (DCs) and secretion of Th-1 type cytokines. The current study demonstrated that a protocol to immunize the C57BL/6 mice with OK-432 followed by treatment with TC-1 lysate can generate markedly increased immune responses of E7-specific CD4(+) T cells and a moderate increase of natural killer (NK) cell, as well as a satisfactorily protective and therapeutic antitumor effect by triggering the DCs to prime T cells. Depletion of lymphocyte subset in vivo suggested that the antitumor effects could be dominantly executed by CD8+ T cells and followed by NK cells, and both of these reactions were induced by the generation of robust E7-specific CD4(+) T helper cell response. These findings warrant OK-432 combination with tumor-lysate as an effective and safe vaccine in future clinical application of cervical cancer.

  7. Vaccination with Necroptotic Cancer Cells Induces Efficient Anti-tumor Immunity

    Directory of Open Access Journals (Sweden)

    Tania Løve Aaes

    2016-04-01

    Full Text Available Successful immunogenic apoptosis in experimental cancer therapy depends on the induction of strong host anti-tumor responses. Given that tumors are often resistant to apoptosis, it is important to identify alternative molecular mechanisms that elicit immunogenic cell death. We have developed a genetic model in which direct dimerization of FADD combined with inducible expression of RIPK3 promotes necroptosis. We report that necroptotic cancer cells release damage-associated molecular patterns and promote maturation of dendritic cells, the cross-priming of cytotoxic T cells, and the production of IFN-γ in response to tumor antigen stimulation. Using both FADD-dependent and FADD-independent RIPK3 induction systems, we demonstrate the efficient vaccination potential of immunogenic necroptotic cells. Our study broadens the current concept of immunogenic cell death and opens doors for the development of new strategies in cancer therapy.

  8. 3-bromopyruvate and buthionine sulfoximine effectively kill anoikis-resistant hepatocellular carcinoma cells.

    Directory of Open Access Journals (Sweden)

    Minjong Lee

    Full Text Available Acquisition of anoikis resistance is a prerequisite for metastasis in hepatocellular carcinoma (HCC. However, little is known about how energy metabolism and antioxidant systems are altered in anoikis-resistant (AR HCC cells. We evaluated anti-tumor effects of a combination treatment of 3-bromopyruvate (3-BP and buthionine sulfoximine (BSO in AR HCC cells.We compared glycolysis, reactive oxygen species (ROS production, and chemoresistance among Huh-BAT, HepG2 HCC cells, and the corresponding AR cells. Expression of hexokinase II, gamma-glutamylcysteine synthetase (rGCS, and epithelial-mesenchymal transition (EMT markers in AR cells was assessed. Anti-tumor effects of a combination treatment of 3-BP and BSO were evaluated in AR cells and an HCC xenograft mouse model.AR HCC cells showed significantly higher chemoresistance, glycolysis and lower ROS production than attached cells. Expression of hexokinase II, rGCS, and EMT markers was higher in AR HCC cells than attached cells. A combination treatment of 3-BP/BSO effectively suppressed proliferation of AR HCC cells through apoptosis by blocking glycolysis and enhancing ROS levels. In xenograft mouse models, tumor growth derived from AR HCC cells was significantly suppressed in the group treated with 3-BP/BSO compared to the group treated with 3-BP or sorafenib.These results demonstrated that a combination treatment of 3-BP/BSO had a synergistic anti-tumor effect in an AR HCC model. This strategy may be an effective adjuvant therapy for patients with sorafenib-resistant HCC.

  9. 3-bromopyruvate and buthionine sulfoximine effectively kill anoikis-resistant hepatocellular carcinoma cells.

    Science.gov (United States)

    Lee, Minjong; Jo, Ara; Lee, Seulki; Kim, Jong Bin; Chang, Young; Nam, Joon Yeul; Cho, Hyeki; Cho, Young Youn; Cho, Eun Ju; Lee, Jeong-Hoon; Yu, Su Jong; Yoon, Jung-Hwan; Kim, Yoon Jun

    2017-01-01

    Acquisition of anoikis resistance is a prerequisite for metastasis in hepatocellular carcinoma (HCC). However, little is known about how energy metabolism and antioxidant systems are altered in anoikis-resistant (AR) HCC cells. We evaluated anti-tumor effects of a combination treatment of 3-bromopyruvate (3-BP) and buthionine sulfoximine (BSO) in AR HCC cells. We compared glycolysis, reactive oxygen species (ROS) production, and chemoresistance among Huh-BAT, HepG2 HCC cells, and the corresponding AR cells. Expression of hexokinase II, gamma-glutamylcysteine synthetase (rGCS), and epithelial-mesenchymal transition (EMT) markers in AR cells was assessed. Anti-tumor effects of a combination treatment of 3-BP and BSO were evaluated in AR cells and an HCC xenograft mouse model. AR HCC cells showed significantly higher chemoresistance, glycolysis and lower ROS production than attached cells. Expression of hexokinase II, rGCS, and EMT markers was higher in AR HCC cells than attached cells. A combination treatment of 3-BP/BSO effectively suppressed proliferation of AR HCC cells through apoptosis by blocking glycolysis and enhancing ROS levels. In xenograft mouse models, tumor growth derived from AR HCC cells was significantly suppressed in the group treated with 3-BP/BSO compared to the group treated with 3-BP or sorafenib. These results demonstrated that a combination treatment of 3-BP/BSO had a synergistic anti-tumor effect in an AR HCC model. This strategy may be an effective adjuvant therapy for patients with sorafenib-resistant HCC.

  10. Fluorescent nanodiamonds engage innate immune effector cells: A potential vehicle for targeted anti-tumor immunotherapy.

    Science.gov (United States)

    Suarez-Kelly, Lorena P; Campbell, Amanda R; Rampersaud, Isaac V; Bumb, Ambika; Wang, Min S; Butchar, Jonathan P; Tridandapani, Susheela; Yu, Lianbo; Rampersaud, Arfaan A; Carson, William E

    2017-04-01

    Fluorescent nanodiamonds (FNDs) are nontoxic, infinitely photostable, and emit fluorescence in the near infrared region. Natural killer (NK) cells and monocytes are part of the innate immune system and are crucial to the control of carcinogenesis. FND-mediated stimulation of these cells may serve as a strategy to enhance anti-tumor activity. FNDs were fabricated with a diameter of 70±28 nm. Innate immune cell FND uptake, viability, surface marker expression, and cytokine production were evaluated in vitro. Evaluation of fluorescence emission from the FNDs was conducted in an animal model. In vitro results demonstrated that treatment of immune cells with FNDs resulted in significant dose-dependent FND uptake, no compromise in cell viability, and immune cell activation. FNDs were visualized in an animal model. Hence, FNDs may serve as novel agents with "track and trace" capabilities to stimulate innate immune cell anti-tumor responses, especially as FNDs are amenable to surface-conjugation with immunomodulatory molecules. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Homeostatic T Cell Expansion to Induce Anti-Tumor Autoimmunity in Breast Cancer

    National Research Council Canada - National Science Library

    Baccala, Roberto

    2007-01-01

    ... that (a) homeostatic T-cell proliferation consistently elicits anti-tumor responses; (b) irradiation is more effective than Tcell depletion by antibodies in inducing anti-tumor responses mediated by homeostatic T-cell proliferation...

  12. Antitumor effect of degalactosylated gc-globulin on orthotopic grafted lung cancer in mice.

    Science.gov (United States)

    Hirota, Keiji; Nakagawa, Yoshinori; Takeuchi, Ryota; Uto, Yoshihiro; Hori, Hitoshi; Onizuka, Shinya; Terada, Hiroshi

    2013-07-01

    Group-specific component (Gc)-globulin-derived macrophage-activating factor (GcMAF) generated by a cascade of catalytic reactions with deglycosidase enzymes exerts antitumor activity. We hypothesized that degalactosyl Gc-globulin (DG3), a precursor of GcMAF, also plays a role in recovery from cancer as well as GcMAF due to progression of deglycosylation by generally resident sialidases and mannosidases. We prepared the subtypes of DG3, such as 1f1f and 1s1s and its 22 homodimers, by using vitamin D3-binding Sepharose CL-6B and examined their antitumor activity in mice bearing Lewis lung carcinoma cells, by counting the number of nodules formed in their lungs. Antitumor activity of DG3 was observed regardless of its subtype, being equivalent to that of GcMAF. The injection route of DG3 affected its antitumor activity, with subcutaneous and intramuscular administration being more favorable than the intraperitoneal or intravenous route. In order to obtain significant antitumor activity, more than 160 ng/kg of DG3 were required. DG3 proved to be promising as an antitumor agent, similarly to GcMAF.

  13. Levels of natural resistance to Boophilus microplus (Acari: Ixodidae in Carora breed bulls

    Directory of Open Access Journals (Sweden)

    Roy D. Meléndez

    1998-09-01

    Full Text Available Boophilus microplus infestation is one of the most serious limitations to cattle industry in tropical regions, even though bovines show natural resistance to ticks. This resistance was evaluated in Cross-bred Carora Bulls (CCB a tropicalized dairy breed from Venezuela. Seven CCB were experimentally infested with B. microplus larvae, "Mozo" strain, they were considered tick-naive because they had never been infested with ticks. The mean inoculum size applied on each bull was 6 477 larvae. After life cycle was completed adult female body weight (BW, egg mass weight (EW, egg hatching rate (%EH, and reproductive index (RI were recorded. Results revealed a high variability in the levels of resistance to B. microplus. Thus, one animal showed greater resistance (Dunnett, p< 0.05 for the analyzed parameters in contrast with three non-resistant bulls. The others had moderate resistance. The trait "resistance" should be included togheter with other traits often used in genetic selection of cattle.

  14. Hydroxyurea derivatives of irofulven with improved antitumor efficacy.

    Science.gov (United States)

    Staake, Michael D; Kashinatham, Alisala; McMorris, Trevor C; Estes, Leita A; Kelner, Michael J

    2016-04-01

    Irofulven is a semi-synthetic derivative of Illudin S, a toxic sesquiterpene isolated from the mushroom Omphalotus illudens. Irofulven has displayed significant antitumor activity in various clinical trials but displayed a limited therapeutic index. A new derivative of irofulven was prepared by reacting hydroxyurea with irofulven under acidic conditions. Acetylation of this new compound with acetic anhydride produced a second derivative. Both of these new derivatives displayed significant antitumor activity in vitro and in vivo comparable to or exceeding that of irofulven. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Naturally selected hepatitis C virus polymorphisms confer broad neutralizing antibody resistance.

    Science.gov (United States)

    Bailey, Justin R; Wasilewski, Lisa N; Snider, Anna E; El-Diwany, Ramy; Osburn, William O; Keck, Zhenyong; Foung, Steven K H; Ray, Stuart C

    2015-01-01

    For hepatitis C virus (HCV) and other highly variable viruses, broadly neutralizing mAbs are an important guide for vaccine development. The development of resistance to anti-HCV mAbs is poorly understood, in part due to a lack of neutralization testing against diverse, representative panels of HCV variants. Here, we developed a neutralization panel expressing diverse, naturally occurring HCV envelopes (E1E2s) and used this panel to characterize neutralizing breadth and resistance mechanisms of 18 previously described broadly neutralizing anti-HCV human mAbs. The observed mAb resistance could not be attributed to polymorphisms in E1E2 at known mAb-binding residues. Additionally, hierarchical clustering analysis of neutralization resistance patterns revealed relationships between mAbs that were not predicted by prior epitope mapping, identifying 3 distinct neutralization clusters. Using this clustering analysis and envelope sequence data, we identified polymorphisms in E2 that confer resistance to multiple broadly neutralizing mAbs. These polymorphisms, which are not at mAb contact residues, also conferred resistance to neutralization by plasma from HCV-infected subjects. Together, our method of neutralization clustering with sequence analysis reveals that polymorphisms at noncontact residues may be a major immune evasion mechanism for HCV, facilitating viral persistence and presenting a challenge for HCV vaccine development.

  16. Advances in induced resistance by natural compounds: towards new options for woody crop protection

    Directory of Open Access Journals (Sweden)

    Eugenio Llorens

    Full Text Available ABSTRACT: The activation of defensive responses of plants is a promising tool for controlling pests in conventional agriculture. Over the last few years, several compounds have been studied to protect crops from pests, without displaying direct toxicity for pathogenic organisms. These compounds have the ability to induce a priming state on the plants that results in resistance (or tolerance against subsequent infection by a pathogen. In terms of molecular response, induced plant defense involves a broad number of physical and biochemical changes such as callose deposition or phenolic compounds, activation of salicylic and/or jasmonic acid pathways or synthesis of defense-related enzymes. Despite the large number of studies performed to ascertain the physiological and biochemical basis of induced resistance, only a few resistance-activating compounds have been studied as a real alternative to classic means of control and the studies geared towards incorporating induced resistance into disease management programs are relatively rare. The incorporation of natural resistance inducer in pest management programs of woody crops, alone or in combination with classical methods, could be a reliable method for reducing the amount of chemical residues in the environment. In this review, we discuss the current knowledge of induced resistance in woody crops, focusing on the mode of action of compounds authorized for conventional agriculture. We conclude by discussing the environmental and economic advantages of applying resistance inducers to conventional agriculture with special emphasis on natural compounds.

  17. Dll4 blockade potentiates the anti-tumor effects of VEGF inhibition in renal cell carcinoma patient-derived xenografts.

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    Kiersten Marie Miles

    Full Text Available The Notch ligand Delta-like 4 (Dll4 is highly expressed in vascular endothelium and has been shown to play a pivotal role in regulating tumor angiogenesis. Blockade of the Dll4-Notch pathway in preclinical cancer models has been associated with non-productive angiogenesis and reduced tumor growth. Given the cross-talk between the vascular endothelial growth factor (VEGF and Delta-Notch pathways in tumor angiogenesis, we examined the activity of a function-blocking Dll4 antibody, REGN1035, alone and in combination with anti-VEGF therapy in renal cell carcinoma (RCC.Severe combined immunodeficiency (SCID mice bearing patient-derived clear cell RCC xenografts were treated with REGN1035 and in combination with the multi-targeted tyrosine kinase inhibitor sunitinib or the VEGF blocker ziv-aflibercept. Immunohistochemical and immunofluorescent analyses were carried out, as well as magnetic resonance imaging (MRI examinations pre and 24 hours and 2 weeks post treatment. Single agent treatment with REGN1035 resulted in significant tumor growth inhibition (36-62% that was equivalent to or exceeded the single agent anti-tumor activity of the VEGF pathway inhibitors sunitinib (38-54% and ziv-aflibercept (46%. Importantly, combination treatments with REGN1035 plus VEGF inhibitors resulted in enhanced anti-tumor effects (72-80% growth inhibition, including some tumor regression. Magnetic resonance imaging showed a marked decrease in tumor perfusion in all treatment groups. Interestingly, anti-tumor efficacy of the combination of REGN1035 and ziv-aflibercept was also observed in a sunitinib resistant ccRCC model.Overall, these findings demonstrate the potent anti-tumor activity of Dll4 blockade in RCC patient-derived tumors and a combination benefit for the simultaneous targeting of the Dll4 and VEGF signaling pathways, highlighting the therapeutic potential of this treatment modality in RCC.

  18. Intratumoral IL-12 and TNF-alpha-loaded microspheres lead to regression of breast cancer and systemic antitumor immunity.

    Science.gov (United States)

    Sabel, Michael S; Skitzki, Joseph; Stoolman, Lloyd; Egilmez, Nejat K; Mathiowitz, Edith; Bailey, Nicola; Chang, Wen-Jian; Chang, Alfred E

    2004-02-01

    Local, sustained delivery of cytokines at a tumor can enhance induction of antitumor immunity and may be a feasible neoadjuvant immunotherapy for breast cancer. We evaluated the ability of intratumoral poly-lactic-acid-encapsulated microspheres (PLAM) containing interleukin 12 (IL-12), tumor necrosis factor alpha (TNF-alpha), and granulocyte-macrophage colony stimulating factor (GM-CSF) in a murine model of breast cancer to generate a specific antitumor response. BALB/c mice with established MT-901 tumors underwent resection or treatment with a single intratumoral injection of PLAM containing IL-12, TNF-alpha, or GM-CSF, alone or in combination. Two weeks later, lymph nodes and spleens were harvested, activated with anti-CD3 monoclonal antibodies (mAb) and rhIL-2, and assessed for antitumor reactivity by an interferon gamma (IFNgamma) release assay. Tumor-infiltrating lymphocyte (TIL) analysis was performed on days 2 and 5 after treatment by mechanically processing the tumors to create a single cell suspension, followed by three-color fluorescence-activated cell sorter (FACS) analysis. Intratumoral injection of cytokine-loaded PLAM significantly suppressed tumor growth, with the combination of IL-12 and TNF-alpha leading to increased infiltration by polymorphonuclear cells and CD8+ T-cells in comparison with controls. The induction of tumor-specific reactive T-cells in the nodes and spleens, as measured by IFN-gamma production, was highest with IL-12 and TNF-alpha. This treatment resulted in resistance to tumor rechallenge. A single intratumoral injection of IL-12 and TNF-alpha-loaded PLAM into a breast tumor leads to infiltration by polymorphonuclear cells and CD8+ T-cells with subsequent tumor regression. In addition, this local therapy induces specific antitumor T-cells in the lymph nodes and spleens, resulting in memory immune response.

  19. Role of efflux pumps and intracellular thiols in natural antimony resistant isolates of Leishmania donovani.

    Directory of Open Access Journals (Sweden)

    Smita Rai

    Full Text Available BACKGROUND: In view of the recent upsurge in the phenomenon of therapeutic failure, drug resistance in Leishmania, developed under natural field conditions, has become a great concern yet little understood. Accordingly, the study of determinants of antimony resistance is urgently warranted. Efflux transporters have been reported in Leishmania but their role in clinical resistance is still unknown. The present study was designed to elucidate the mechanism of natural antimony resistance in L. donovani field isolates by analyzing the functionality of efflux pump(s and expression profiles of known genes involved in transport and thiol based redox metabolism. METHODOLOGY/PRINCIPAL FINDINGS: We selected 7 clinical isolates (2 sensitive and 5 resistant in addition to laboratory sensitive reference and SbIII resistant mutant strains for the present study. Functional characterization using flow cytometry identified efflux pumps that transported substrates of both P-gp and MRPA and were inhibited by the calmodulin antagonist trifluoperazine. For the first time, verapamil sensitive efflux pumps for rhodamine 123 were observed in L. donovani that were differentially active in resistant isolates. RT-PCR confirmed the over-expression of MRPA in isolates with high resistance index only. Resistant isolates also exhibited consistent down regulation of AQP1 and elevated intracellular thiol levels which were accompanied with increased expression of ODC and TR genes. Interestingly, γ-GCS is not implicated in clinical resistance in L. donovani isolates. CONCLUSIONS/SIGNIFICANCE: Here we demonstrate for the first time, the role of P-gp type plasma membrane efflux transporter(s in antimony resistance in L. donovani field isolates. Further, decreased levels of AQP1 and elevated thiols levels have emerged as biomarkers for clinical resistance.

  20. Celecoxib decreases growth and angiogenesis and promotes apoptosis in a tumor cell line resistant to chemotherapy

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    Carlos Rosas

    2014-01-01

    Full Text Available BACKGROUND: During the last few years it has been shown in several laboratories that Celecoxib (Cx, a non-steroidal anti-inflammatory agent (NSAID normally used for pain and arthritis, mediates antitumor and antiangiogenic effects. However, the effects of this drug on a tumor cell line resistant to chemotherapeutical drugs used in cancer have not been described. Herein we evaluate the angiogenic and antitumor effects of Cx in the development of a drug-resistant mammary adenocarcinoma tumor (TA3-MTXR. RESULTS: Cx reduces angiogenesis in the chick embryonic chorioallantoic membrane assay (CAM, inhibits the growth and microvascular density of the murine TA3-MTXR tumor, reduces microvascular density of tumor metastases, promotes apoptosis and reduces vascular endothelial growth factor (VEGF production and cell proliferation in the tumor. CONCLUSION: The antiangiogenic and antitumor Cx effects correlate with its activity on other tumor cell lines, suggesting that Prostaglandins (PGs and VEGF production are involved. These results open the possibility of using Celecoxib combined with other experimental therapies, ideally aiming to get synergic effects.

  1. EFFECTS OF EXTRACTIVES AND DENSITY ON NATURAL RESISTANCE OF WOODS TO TERMITE Nasutitermes corniger

    Directory of Open Access Journals (Sweden)

    Juarez Benigno Paes

    2015-12-01

    Full Text Available The evaluation of the natural resistance of wood to wood-destroying organisms is of fundamental importance in the choice of species to be used in buildings and furniture industry. Thus, the effects of extractives and wood density on biological resistance of Acacia mangium, Casuarina equisetifolia, Corymbia torelliana, Eucalyptus cloeziana, Tectona grandis and Caesalpinia echinata woods to the xylophagous termite Nasutitermes corniger was evaluated under laboratory conditions. Test samples, with dimensions of 2.00 x 2.54 x 0.64 cm (radial x tangential x longitudinal in four positions in pith-bark direction (internal heart, intermediate heart, outer heart and sapwood were taken. The woods were exposed to termite action for 28 days in no-choice feeding test. The samples not selected for the termite test were turned into sawdust and the extractive contents were obtained using the shavings that passed through the sieve of 40 and were retained in the sieve of 60 mesh. The wood natural resistance, within the pith-bark positions, for the studied species, is not correlated with the density and extractive content. However, among the woods, those with higher density and extractive content are more resistant. The woods with greater biological resistance to the termite Nasutitermes corniger (smaller mass loss, waste and survival time of insects are Corymbia torelliana and Caesalpinia echinata and of less resistance is Casuarina equisetifolia.

  2. Antitumor Immunity Is Controlled by Tetraspanin Proteins

    Directory of Open Access Journals (Sweden)

    Fleur Schaper

    2018-05-01

    Full Text Available Antitumor immunity is shaped by the different types of immune cells that are present in the tumor microenvironment (TME. In particular, environmental signals (for instance, soluble factors or cell–cell contact transmitted through the plasma membrane determine whether immune cells are activated or inhibited. Tetraspanin proteins are emerging as central building blocks of the plasma membrane by their capacity to cluster immune receptors, enzymes, and signaling molecules into the tetraspanin web. Whereas some tetraspanins (CD81, CD151, CD9 are widely and broadly expressed, others (CD53, CD37, Tssc6 have an expression pattern restricted to hematopoietic cells. Studies using genetic mouse models have identified important immunological functions of these tetraspanins on different leukocyte subsets, and as such, may be involved in the immune response against tumors. While multiple studies have been performed with regards to deciphering the function of tetraspanins on cancer cells, the effect of tetraspanins on immune cells in the antitumor response remains understudied. In this review, we will focus on tetraspanins expressed by immune cells and discuss their potential role in antitumor immunity. New insights in tetraspanin function in the TME and possible prognostic and therapeutic roles of tetraspanins will be discussed.

  3. Antitumor activity in RAS-driven tumors by blocking AKT and MEK.

    Science.gov (United States)

    Tolcher, Anthony W; Khan, Khurum; Ong, Michael; Banerji, Udai; Papadimitrakopoulou, Vassiliki; Gandara, David R; Patnaik, Amita; Baird, Richard D; Olmos, David; Garrett, Christopher R; Skolnik, Jeffrey M; Rubin, Eric H; Smith, Paul D; Huang, Pearl; Learoyd, Maria; Shannon, Keith A; Morosky, Anne; Tetteh, Ernestina; Jou, Ying-Ming; Papadopoulos, Kyriakos P; Moreno, Victor; Kaiser, Brianne; Yap, Timothy A; Yan, Li; de Bono, Johann S

    2015-02-15

    KRAS is the most commonly mutated oncogene in human tumors. KRAS-mutant cells may exhibit resistance to the allosteric MEK1/2 inhibitor selumetinib (AZD6244; ARRY-142886) and allosteric AKT inhibitors (such as MK-2206), the combination of which may overcome resistance to both monotherapies. We conducted a dose/schedule-finding study evaluating MK-2206 and selumetinib in patients with advanced treatment-refractory solid tumors. Recommended dosing schedules were defined as MK-2206 at 135 mg weekly and selumetinib at 100 mg once daily. Grade 3 rash was the most common dose-limiting toxicity (DLT); other DLTs included grade 4 lipase increase, grade 3 stomatitis, diarrhea, and fatigue, and grade 3 and grade 2 retinal pigment epithelium detachment. There were no meaningful pharmacokinetic drug-drug interactions. Clinical antitumor activity included RECIST 1.0-confirmed partial responses in non-small cell lung cancer and low-grade ovarian carcinoma. Responses in KRAS-mutant cancers were generally durable. Clinical cotargeting of MEK and AKT signaling may be an important therapeutic strategy in KRAS-driven human malignancies (Trial NCT number NCT01021748). ©2014 American Association for Cancer Research.

  4. Hepatic natural killer cells exclusively kill splenic/blood natural killer-resistant tumor cells by the perforin/granzyme pathway

    NARCIS (Netherlands)

    Vermijlen, David; Luo, Dianzhong; Froelich, Christopher J.; Medema, Jan Paul; Kummer, Jean Alain; Willems, Erik; Braet, Filip; Wisse, Eddie

    2002-01-01

    Hepatic natural killer (NK) cells are located in the liver sinusoids adherent to the endothelium. Human and rat hepatic NK cells induce cytolysis in tumor cells that are resistant to splenic or blood NK cells. To investigate the mechanism of cell death, we examined the capacity of isolated, pure

  5. Natural convection heat transfer between vertical channel with flow resistance at the lower end

    International Nuclear Information System (INIS)

    Iwamoto, S.; Nishimura, S.; Ishihara, I.

    2003-01-01

    For natural convection in the geometrically complicated channel, the convection flow is suppressed by flow resistance due to such channel itself and the lopsided flow may take place. This could result in serious influences on the heat transfer in the channel. In order to investigate fundamentally the natural convection flow and heat transfer in such the channel, the vertical channel in which wall was heated with uniform heat flux and the flow resistance was given by small clearance between the lower end of channel and a wide horizontal floor. Flow pattern was observed by illuminating smoke filled in the channel and heat transfer rate was measured. (author)

  6. Cacao families and parents selected as resistant to natural infection of Moniliophthora perniciosa

    Directory of Open Access Journals (Sweden)

    Carolina S. Benjamin

    2016-07-01

    Full Text Available The known sources of resistance to witches’ broom (WB, a severe disease of cacao, are limited. Aiming to identify families and parents resistant to Moniliophthora perniciosa, a population of 22 families was evaluated by assessing the number of brooms formed per tree during 10 years under field conditions. The population was established in randomized blocks with three replications of 12 plants each. Significant differences were observed among families. The most outstanding families were NA33 x RB39 and RB39 x P4B, which presented the lowest WB incidence during 10 years. The increase in natural field infection of Scavina clones families and their descendants were clearly demonstrated after 2006. The existence of additive effects for resistance appears clearly for families, which had other source of resistance associated with Scavina. Clones RB39, RB36, P4B, NA33 and CSUL3 are promising parents for pyramiding resistance genes and increasing the stability and durability of resistance to WB.

  7. A novel ABCG-like transporter of Trypanosoma cruzi is involved in natural resistance to benznidazole

    Directory of Open Access Journals (Sweden)

    Bianca Zingales

    2015-05-01

    Full Text Available Benznidazole (BZ is one of the two drugs used for Chagas disease treatment. Nevertheless therapeutic failures of BZ have been reported, which were mostly attributed to variable drug susceptibility among Trypanosoma cruzi strains. ATP-binding cassette (ABC transporters are involved in a variety of translocation processes and some members have been implicated in drug resistance. Here we report the characterisation of the first T. cruzi ABCG transporter gene, named TcABCG1, which is over-expressed in parasite strains naturally resistant to BZ. Comparison of TcABCG1 gene sequence of two TcI BZ-resistant strains with CL Brener BZ-susceptible strain showed several single nucleotide polymorphisms, which determined 11 amino acid changes. CL Brener transfected with TcI transporter genes showed 40-47% increased resistance to BZ, whereas no statistical significant increment in drug resistance was observed when CL Brener was transfected with the homologous gene. Only in the parasites transfected with TcI genes there was 2-2.6-fold increased abundance of TcABCG1 transporter protein. The analysis in wild type strains also suggests that the level of TcABCG1 transporter is related to BZ natural resistance. The characteristics of untranslated regions of TcABCG1 genes of BZ-susceptible and resistant strains were investigated by computational tools.

  8. Antitumor and angiostatic peptides from frog skin secretions.

    Science.gov (United States)

    van Zoggel, Hanneke; Hamma-Kourbali, Yamina; Galanth, Cécile; Ladram, Ali; Nicolas, Pierre; Courty, José; Amiche, Mohamed; Delbé, Jean

    2012-01-01

    The discovery of new molecules with potential antitumor activity continues to be of great importance in cancer research. In this respect, natural antimicrobial peptides isolated from various animal species including humans and amphibians have been found to be of particular interest. Here, we report the presence of two anti-proliferative peptides active against cancer cells in the skin secretions of the South American tree frog, Phyllomedusa bicolor. The crude skin exudate was fractioned by size exclusion gel followed by reverse-phase HPLC chromatography. After these two purification steps, we identified two fractions that exhibited anti-proliferative activity. Sequence analysis indicated that this activity was due to two antimicrobial α-helical cationic peptides of the dermaseptin family (dermaseptins B2 and B3). This result was confirmed using synthetic dermaseptins. When tested in vitro, synthetic B2 and B3 dermaseptins inhibited the proliferation of the human prostatic adenocarcinoma PC-3 cell line by more than 90%, with an EC(50) of around 2-3 μM. No effect was observed on the growth of the NIH-3T3 non-tumor mouse cell line with Drs B2, whereas a slight inhibiting effect was observed with Drs B3 at high dose. In addition, the two fractions obtained after size exclusion chromatography also inhibited PC-3 cell colony formation in soft agar. Interestingly, inhibition of the proliferation and differentiation of activated adult bovine aortic endothelial cells was observed in cells treated with these two fractions. Dermaseptins B2 and B3 could, therefore, represent interesting new pharmacological molecules with antitumor and angiostatic properties for the development of a new class of anticancer drugs.

  9. ENHANCEMENT OF RESISTANCE TO OXIDATIVE DEGRADATION OF NATURAL RUBBER THROUGH LATEX DEGRADATION

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    A fully characterised natural rubber latex was subjected to mechanical degradation by stirring at intervals. The resistance to oxidative degradation of the different samples were studied by measuring the Plasticity retention indices (PRI).The results show that there is an enhancement of the PRI from 57% for the undegraded rubber to 79% for the one-hour degraded sample. Further degradation resulted in decrease of PRI as time of degradation increased. Therefore, the one-hour degraded sample is a special rubber with high oxidation resistance which is of great importance in engineering.

  10. Antitumor effect of combination of the inhibitors of two new oncotargets: proton pumps and reverse transcriptase.

    Science.gov (United States)

    Lugini, Luana; Sciamanna, Ilaria; Federici, Cristina; Iessi, Elisabetta; Spugnini, Enrico Pierluigi; Fais, Stefano

    2017-01-17

    Tumor therapy needs new approaches in order to improve efficacy and reduce toxicity of the current treatments. The acidic microenvironment and the expression of high levels of endogenous non-telomerase reverse transcriptase (RT) are common features of malignant tumor cells. The anti-acidic proton pump inhibitor Lansoprazole (LAN) and the non-nucleoside RT inhibitor Efavirenz (EFV) have shown independent antitumor efficacy. LAN has shown to counteract drug tumor resistance. We tested the hypothesis that combination of LAN and EFV may improve the overall antitumor effects. We thus pretreated human metastatic melanoma cells with LAN and then with EFV, both in 2D and 3D spheroid models. We evaluated the treatment effect by proliferation and cell death/apoptosis assays in classical and in pulse administration experiments. The action of EFV was negatively affected by the tumor microenvironmental acidity, and LAN pretreatment overcame the problem. LAN potentiated the cytotoxicity of EFV to melanoma cells and, when administered during the drug interruption period, prevented the replacement of tumor cell growth.This study supports the implementation of the current therapies with combination of Proton Pumps and Reverse Transcriptase inhibitors.

  11. Anti-tumor activities of luteolin and silibinin in glioblastoma cells: overexpression of miR-7-1-3p augmented luteolin and silibinin to inhibit autophagy and induce apoptosis in glioblastoma in vivo.

    Science.gov (United States)

    Chakrabarti, Mrinmay; Ray, Swapan K

    2016-03-01

    Glioblastoma is the deadliest brain tumor in humans. High systemic toxicity of conventional chemotherapies prompted the search for natural compounds for controlling glioblastoma. The natural flavonoids luteolin (LUT) and silibinin (SIL) have anti-tumor activities. LUT inhibits autophagy, cell proliferation, metastasis, and angiogenesis and induces apoptosis; while SIL activates caspase-8 cascades to induce apoptosis. However, synergistic anti-tumor effects of LUT and SIL in glioblastoma remain unknown. Overexpression of tumor suppressor microRNA (miR) could enhance the anti-tumor effects of LUT and SIL. Here, we showed that 20 µM LUT and 50 µM SIL worked synergistically for inhibiting growth of two different human glioblastoma U87MG (wild-type p53) and T98G (mutant p53) cell lines and natural combination therapy was more effective than conventional chemotherapy (10 µM BCNU or 100 µM TMZ). Combination of LUT and SIL caused inhibition of growth of glioblastoma cells due to induction of significant amounts of apoptosis and complete inhibition of invasion and migration. Further, combination of LUT and SIL inhibited rapamycin (RAPA)-induced autophagy, a survival mechanism, with suppression of PKCα and promotion of apoptosis through down regulation of iNOS and significant increase in expression of the tumor suppressor miR-7-1-3p in glioblastoma cells. Our in vivo studies confirmed that overexpression of miR-7-1-3p augmented anti-tumor activities of LUT and SIL in RAPA pre-treated both U87MG and T98G tumors. In conclusion, our results clearly demonstrated that overexpression of miR-7-1-3p augmented the anti-tumor activities of LUT and SIL to inhibit autophagy and induce apoptosis for controlling growth of different human glioblastomas in vivo.

  12. Immunopotentiation by a new antitumor polysaccharide, DMG, a degraded D-manno-D-glucan from Microellobosporia grisea culture fluid.

    Science.gov (United States)

    Nakajima, H; Kita, Y; Takashi, T; Akasaki, M; Yamaguchi, F; Ozawa, S; Tsukada, W; Abe, S; Mizuno, D

    1984-03-01

    The immunopharmacological behavior of DMG, an antitumor polysaccharide, was studied in mice. DMG administered ip or sc stimulated peritoneal macrophages to produce high levels of interleukin-1 activity, which can amplify successive immune responses. DMG dose-dependently and schedule-dependently increased the cellular immune response against allogeneic tumor cells and the humoral immune response to sheep erythrocytes. DMG also enhanced nonspecific antitumor effector functions, such as natural killer activity of spleen and peritoneal cells, and the cytostatic activity of peritoneal macrophages. Peritoneal macrophages activated by ip or sc injection of DMG exhibited high cytostatic activity, especially after exposure in vitro to lymphokine supernatants containing macrophage activation factor. Moreover, granulocyte/macrophage colony-stimulating activity in the serum increased 2-10 hr after DMG administration. Thus, DMG potentiated antigen-specific immunological functions and nonspecific functions of host defense systems against cancer both qualitatively and quantitatively.

  13. Study on the Immunomodulation Effect of Isodon japonicus Extract via Splenocyte Function and NK Anti-Tumor Activity

    Directory of Open Access Journals (Sweden)

    Kyung-A Hwang

    2012-04-01

    Full Text Available Here we investigated the potential immune-enhancing activity of Isodon japonicus on murine splenocyte and natural-killer (NK cells in vitro. The ethanol extract of I. japonicus significantly enhanced the proliferation of splenocyte and induced the significant enhancement of NK cells’ activity against tumor cells (YAC-1. In addition, I. japonicus increased the production of interferon (IFN-γ and tumor necrosis factor (TNF-α, suggesting that the increase in NK cell cytotoxicity could be due to the enhancement of the NK cell production of both cytokines. Taken together, I. japonicus extract inhibited the growth of human leukemia cells (K562 by 74%. Our observation indicated that the anti-tumor effects of I. japonicus may be attributed to its ability to serve as a stimulant of NK anti-tumor activity. In addition, our results support the development of functional food studies on I. japonicus.

  14. Ethacrynic acid improves the antitumor effects of irreversible epidermal growth factor receptor tyrosine kinase inhibitors in breast cancer.

    Science.gov (United States)

    Liu, Bing; Huang, XinPing; Hu, YunLong; Chen, TingTing; Peng, BoYa; Gao, NingNing; Jin, ZhenChao; Jia, TieLiu; Zhang, Na; Wang, ZhuLin; Jin, GuangYi

    2016-09-06

    Prolonged treatment of breast cancer with epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) often results in acquired resistance and a narrow therapeutic index. One strategy to improve the therapeutic effects of EGFR TKIs is to combine them with drugs used for other clinical indications. Ethacrynic acid (EA) is an FDA approved drug that may have antitumor effects and may enhance the cytotoxicity of chemotherapeutic agents by binding to glutathione and inhibiting WNT signaling. While the α,β-unsaturated-keto structure of EA is similar to that of irreversible TKIs, the mechanism of action of EA when combined with irreversible EGFR TKIs in breast cancer remains unknown. We therefore investigated the combination of irreversible EGFR TKIs and EA. We found that irreversible EGFR TKIs and EA synergistically inhibit breast cancer both in vitro and in vivo. The combination of EGFR TKIs and EA induces necrosis and cell cycle arrest and represses WNT/β-catenin signaling as well as MAPK-ERK1/2 signaling. We conclude that EA synergistically enhances the antitumor effects of irreversible EGFR TKIs in breast cancer.

  15. Resistance to RadLV-induced leukemia: non-participation of splenic natural killer cells

    International Nuclear Information System (INIS)

    St-Pierre, Y.; Hugo, P.; Lemieux, S.; Lussier, G.; Potworowski, E.F.

    1988-01-01

    The phenotypic expression of genetically determined resistance to radiation leukemia virus (RadLV)-induced leukemia in mice has been shown to reside in the bone marrow. Because the bone marrow contains precursors of natural killer (NK) cells, known to play a role in retrovirally induced infections, and because these cells have been suggested as participating in resistance to radiation-induced leukemia, it was pertinent to establish whether their levels differed in strains of mice susceptible and resistant to leukemia. We therefore tested splenic NK cell levels in C57BL/Ka (susceptible) and B10.A(5R) (resistant) mice before viral inoculation, immediately after viral inoculation, and throughout the preleukemic period and showed that they were not different. This indicates that splenic NK cell levels have no bearing on the resistance to RadLV-induced leukemia and that other immune or non-immune mechanisms must be sought

  16. Redox cycling of potential antitumor aziridinylquinones

    NARCIS (Netherlands)

    Lusthof, Klaas J.; de Mol, Nicolaas J.; Richter, Wilma; Janssen, Lambert H.M.; Butler, John; Hoey, Brigid M.; Verboom, Willem; Reinhoudt, David

    1992-01-01

    The formation of reactive oxygen intermediates (ROI) during redox cycling of newly synthetized potential antitumor 2,5-bis (1-aziridinyl)-1,4-benzoquinone (BABQ) derivatives has been studied by assaying the production of ROI (superoxide, hydroxyl radical, and hydrogen peroxide) by xanthine oxidase

  17. Melatonin enhances the anti-tumor effect of fisetin by inhibiting COX-2/iNOS and NF-κB/p300 signaling pathways.

    Directory of Open Access Journals (Sweden)

    Canhui Yi

    Full Text Available Melatonin is a hormone identified in plants and pineal glands of mammals and possesses diverse physiological functions. Fisetin is a bio-flavonoid widely found in plants and exerts antitumor activity in several types of human cancers. However, the combinational effect of melatonin and fisetin on antitumor activity, especially in melanoma treatment, remains unclear. Here, we tested the hypothesis that melatonin could enhance the antitumor activity of fisetin in melanoma cells and identified the underlying molecular mechanisms. The combinational treatment of melanoma cells with fisetin and melatonin significantly enhanced the inhibitions of cell viability, cell migration and clone formation, and the induction of apoptosis when compared with the treatment of fisetin alone. Moreover, such enhancement of antitumor effect by melatonin was found to be mediated through the modulation of the multiply signaling pathways in melanoma cells. The combinational treatment of fisetin with melatonin increased the cleavage of PARP proteins, triggered more release of cytochrome-c from the mitochondrial inter-membrane, enhanced the inhibition of COX-2 and iNOS expression, repressed the nuclear localization of p300 and NF-κB proteins, and abrogated the binding of NF-κB on COX-2 promoter. Thus, these results demonstrated that melatonin potentiated the anti-tumor effect of fisetin in melanoma cells by activating cytochrome-c-dependent apoptotic pathway and inhibiting COX-2/iNOS and NF-κB/p300 signaling pathways, and our study suggests the potential of such a combinational treatment of natural products in melanoma therapy.

  18. Melatonin Enhances the Anti-Tumor Effect of Fisetin by Inhibiting COX-2/iNOS and NF-κB/p300 Signaling Pathways

    Science.gov (United States)

    Yu, Zhenlong; Xiao, Yao; Wang, Jingshu; Qiu, Huijuan; Yu, Wendan; Tang, Ranran; Yuan, Yuhui; Guo, Wei; Deng, Wuguo

    2014-01-01

    Melatonin is a hormone identified in plants and pineal glands of mammals and possesses diverse physiological functions. Fisetin is a bio-flavonoid widely found in plants and exerts antitumor activity in several types of human cancers. However, the combinational effect of melatonin and fisetin on antitumor activity, especially in melanoma treatment, remains unclear. Here, we tested the hypothesis that melatonin could enhance the antitumor activity of fisetin in melanoma cells and identified the underlying molecular mechanisms. The combinational treatment of melanoma cells with fisetin and melatonin significantly enhanced the inhibitions of cell viability, cell migration and clone formation, and the induction of apoptosis when compared with the treatment of fisetin alone. Moreover, such enhancement of antitumor effect by melatonin was found to be mediated through the modulation of the multiply signaling pathways in melanoma cells. The combinational treatment of fisetin with melatonin increased the cleavage of PARP proteins, triggered more release of cytochrome-c from the mitochondrial inter-membrane, enhanced the inhibition of COX-2 and iNOS expression, repressed the nuclear localization of p300 and NF-κB proteins, and abrogated the binding of NF-κB on COX-2 promoter. Thus, these results demonstrated that melatonin potentiated the anti-tumor effect of fisetin in melanoma cells by activating cytochrome-c-dependent apoptotic pathway and inhibiting COX-2/iNOS and NF-κB/p300 signaling pathways, and our study suggests the potential of such a combinational treatment of natural products in melanoma therapy. PMID:25000190

  19. Optimized adhesives for strong, lightweight, damage-resistant, nanocomposite materials: new insights from natural materials

    International Nuclear Information System (INIS)

    Hansma, P K; Turner, P J; Ruoff, R S

    2007-01-01

    From our investigations of natural composite materials such as abalone shell and bone we have learned the following. (1) Nature is frugal with resources: it uses just a few per cent glue, by weight, to glue together composite materials. (2) Nature does not avoid voids. (3) Nature makes optimized glues with sacrificial bonds and hidden length. We discuss how optimized adhesives combined with high specific stiffness/strength structures such as carbon nanotubes or graphene sheets could yield remarkably strong, lightweight, and damage-resistant materials

  20. Optimized adhesives for strong, lightweight, damage-resistant, nanocomposite materials: new insights from natural materials

    Energy Technology Data Exchange (ETDEWEB)

    Hansma, P K [Physics Department, Broida Hall, University of California, Santa Barbara, CA 93106 (United States); Turner, P J [Physics Department, Broida Hall, University of California, Santa Barbara, CA 93106 (United States); Ruoff, R S [Department of Mechanical Engineering, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208-3111 (United States)

    2007-01-31

    From our investigations of natural composite materials such as abalone shell and bone we have learned the following. (1) Nature is frugal with resources: it uses just a few per cent glue, by weight, to glue together composite materials. (2) Nature does not avoid voids. (3) Nature makes optimized glues with sacrificial bonds and hidden length. We discuss how optimized adhesives combined with high specific stiffness/strength structures such as carbon nanotubes or graphene sheets could yield remarkably strong, lightweight, and damage-resistant materials.

  1. Antitumor-promoting activity of scopadulcic acid B, isolated from the medicinal plant Scoparia dulcis L.

    Science.gov (United States)

    Nishino, H; Hayashi, T; Arisawa, M; Satomi, Y; Iwashima, A

    1993-01-01

    Scopadulcic acid B (SDB), a tetracyclic diterpenoid isolated from a medicinal plant, Scoparia dulcis L., inhibited the effects of tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) in vitro and in vivo; SDB inhibited TPA-enhanced phospholipid synthesis in cultured cells, and also suppressed the promoting effect of TPA on skin tumor formation in mice initiated with 7,12-dimethylbenz[a]anthracene. The potency of SDB proved to be stronger than that of other natural antitumor-promoting terpenoids, such as glycyrrhetinic acid.

  2. In vitro and in vivo antitumor efficacy of berberine-nanostructured lipid carriers against H22 tumor

    Science.gov (United States)

    Wang, Zhi-ping; Wu, Jun-biao; Chen, Tong-sheng; Zhou, Qun; Wang, Yi-fei

    2015-03-01

    Hepatocarcinoma, a malignant cancer, threaten human life badly. It is a current issue to seek the effective natural remedy from plant to treat cancer due to the resistance of the advanced hepatocarcinoma to chemotherapy. Berberine (Ber), an isoquinoline derivative alkaloid, has a wide range of pharmacological properties and is considered to have anti-hepatocarcinoma effects. However its low oral bioavailability restricts its wide application. In this report, Ber loaded nanostructured lipid carriers (Ber-NLC) was prepared by hot melting and then high pressure homogenization technique. Both in vitro and in vivo anti-hepatocarcinoma effects of Ber-NLC relative to efficacy of bulk Ber were evaluated. The particle size and zeta potential of Ber-NLC were 189.3 nm and -19.3 mV, respectively. MTT assay showed that Ber-NLC effectively inhibited the proliferation of H22 cells, and the corresponding IC50 values were 6.3 μg/ml (22.1 μg/ml of bulk Ber). In vivo studies also showed higher antitumor efficacy, and inhibition rates was 68.3 % (41.4 % of bulk Ber) at 100 mg/kg intragastric administration in the H22 solid tumor bearing mice. These results suggest that the delivery of Ber-NLC is a promising approach for treating tumors.

  3. Assessment of antitumoral and antimicrobial effects of a maslinic acid derivative

    Directory of Open Access Journals (Sweden)

    Ioana Z. Pavel

    2016-12-01

    Full Text Available INTRODUCTION Maslinic acid, a naturally occurring triterpene, has been reported to possess several therapeutic effects including antioxidant, anti-inflammatory and antiparasitic properties. Structural changes of the compound led to the development of new derivatives in order to expand the spectrum of activities. OBJECTIVES AND BACKGROUND The present study was purposed to assess the in vitro antitumoral and antibacterial effects of a maslinic acid derivative, namely benzyl (2α, 3β 2,3-diacetoxy-olean-12- en-28-amide (EM2. MATERIALS AND METHODS Four compound concentrations (12.5, 25, 50 and 100 µM were evaluated for their cytotoxic effect on A375 human melanoma and B164A5 murine melanoma cell lines using the MTT assay. Furthermore, EM2 was tested on ten bacterial strains by means of agar disk diffusion method with the assessment of the inhibition zone diameters at 24h period of time. RESULTS EM2 elicited a dose-dependent cytotoxic effect on both melanoma cell lines. Regarding the antibacterial activity, EM2 determined a significant growth inhibition on Streptococcus pyogenes (20 ± 0.26 mm and Staphylococcus aureus (13 ± 0.19 mm. CONCLUSIONS The tested maslinic acid derivative is a promising antitumoral agent against skin cancer and antimicrobial agent against cocci bacteria. Graphical abstract: EM2 in vitro effects

  4. Antitumor effects and mechanisms of Ganoderma extracts and spores oil

    OpenAIRE

    Chen, Chun; Li, Peng; Li, Ye; Yao, Guan; Xu, Jian-Hua

    2016-01-01

    Ganoderma lucidum is a popular herbal medicine used in China to promote health. Modern studies have disclosed that the active ingredients of Ganoderma can exhibit several effects, including antitumor effects and immunomodulation. The present study evaluated the antitumor effects of self-prepared Ganoderma extracts and spores oil, and investigated the possible underlying mechanisms by observing the effects of the extracts and oil on topoisomerases and the cell cycle. The results showed that Ga...

  5. New cysteamine (2-chloroethyl)nitrosoureas. Synthesis and preliminary antitumor results.

    Science.gov (United States)

    Madelmont, J C; Godeneche, D; Parry, D; Duprat, J; Chabard, J L; Plagne, R; Mathe, G; Meyniel, G

    1985-09-01

    Three chemical pathways were used for the synthesis of four new N'-(2-chloroethyl)-N-[2-(methylsulfinyl)ethyl]- and N'-(2-chloroethyl)-N-[2-(methylsulfonyl)ethyl]-N- or N'-nitrosoureas. These compounds are plasma metabolites of CNCC, a promising antineoplastic (2-chloroethyl)nitrosourea. Preliminary antitumor evaluation was performed against L1210 leukemia implanted intraperitoneally in mice. Among these compounds, two of them exhibited a greater antitumor activity compared to that of the parent mixture.

  6. Immunotherapeutic effect of Concholepas hemocyanin in the murine bladder cancer model: evidence for conserved antitumor properties among hemocyanins.

    Science.gov (United States)

    Moltedo, Bruno; Faunes, Fernando; Haussmann, Denise; De Ioannes, Pablo; De Ioannes, Alfredo E; Puente, Javier; Becker, María Inés

    2006-12-01

    We determined the antitumor properties of a newly available hemocyanin obtained from the Chilean gastropod Concholepas concholepas (Biosonda Corp., Santiago, Chile) in a syngeneic heterotopic mouse bladder carcinoma model. Since keyhole limpet hemocyanin (Pierce, Rockford, Illinois) is used increasingly in biomedicine as a carrier for vaccines and an immunotherapeutic agent for bladder transitional cell carcinoma, there is a growing interest in finding new substances that share its potent immunomodulatory properties. Considering that keyhole limpet hemocyanin and Concholepas concholepas hemocyanin differ significantly, it was not possible to predict a priori the antitumor properties of Concholepas concholepas hemocyanin. C3H/He mice were primed with Concholepas concholepas hemocyanin before subcutaneous implantation of mouse bladder tumor-2 cells. Treatment consisted of a subcutaneous dose of Concholepas concholepas hemocyanin (1 mg or 100 mug) at different intervals after implantation. Keyhole limpet hemocyanin and phosphate buffered saline served as positive and negative controls, respectively. In addition, experiments were designed to determine which elements of the immune response were involved in its adjuvant immunostimulatory effect. Mice treated with Concholepas concholepas hemocyanin showed a significant antitumor effect, as demonstrated by decreased tumor growth and incidence, prolonged survival and lack of toxic effects. These effects were similar to those achieved with keyhole limpet hemocyanin. We found that each hemocyanin increased natural killer cell activity but the effect of Concholepas concholepas hemocyanin was stronger. Analysis of serum from treated mice showed an increased interferon-gamma and low interleukin-4, which correlated with antibody isotypes, confirming that hemocyanins induce a T helper type 1 cytokine profile. To our knowledge our results are the first demonstration of the antitumor effect of a hemocyanin other than keyhole limpet

  7. L-Aspartic and l-glutamic acid ester-based ProTides of anticancer nucleosides: Synthesis and antitumoral evaluation.

    Science.gov (United States)

    Gao, Ling-Jie; De Jonghe, Steven; Daelemans, Dirk; Herdewijn, Piet

    2016-05-01

    A series of novel aryloxyphosphoramidate nucleoside prodrugs based on l-aspartic acid and l-glutamic acid as amino acid motif has been synthesized and evaluated for antitumoral activity. Depending on the cancer cell line studied and on the nature of the parent nucleoside compound (gemcitabine, 5-iodo-2'-deoxy-uridine, floxuridine or brivudin), the corresponding ProTides are endowed with an improved or decreased cytotoxic activity. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Targeting tumor-associated macrophages by anti-tumor Chinese materia medica.

    Science.gov (United States)

    Pu, Wei-Ling; Sun, Li-Kang; Gao, Xiu-Mei; Rüegg, Curzio; Cuendet, Muriel; Hottiger, Micheal O; Zhou, Kun; Miao, Lin; Zhang, Yun-Sha; Gebauer, Margaret

    2017-10-01

    Tumor-associated macrophages (TAMs) play a key role in all stages of tumorigenesis and tumor progression. TAMs secrete different kinds of cytokines, chemokines, and enzymes to affect the progression, metastasis, and resistance to therapy depending on their state of reprogramming. Therapeutic benefit in targeting TAMs suggests that macrophages are attractive targets for cancer treatment. Chinese materia medica (CMM) is an important approach for treating cancer in China and in the Asian region. According to the theory of Chinese medicine (CM) and its practice, some prescriptions of CM regulate the body's internal environment possibly including the remodeling the tumor microenvironment (TME). Here we briefly summarize the pivotal effects of TAMs in shaping the TME and promoting tumorigenesis, invasion, metastasis and immunosuppression. Furthermore, we illustrate the effects and mechanisms of CMM targeting TAMs in antitumor therapy. Finally, we reveal the CMM's dual-regulatory and multi-targeting functions on regulating TAMs, and hopefully, provide the theoretical basis for CMM clinical practice related to cancer therapy.

  9. Study on fluorouracil–chitosan nanoparticle preparation and its antitumor effect

    Directory of Open Access Journals (Sweden)

    Gaimin Chen

    2016-05-01

    Full Text Available To successfully prepare fluorouracil–chitosan nanoparticles, and further analyze its anti-tumor activity mechanism, this paper makes a comprehensive study of existing preparation prescription and makes a detailed analysis of fluorouracil–chitosan in vitro release and pharmacodynamic behavior of animals. Two-step synthesis method is adopted to prepare 5-FU–CS–mPEG prodrugs, and infrared, 1H NMR and differential thermal analysis are adopted to analyze characterization synthetic products of prepared drugs. To ensure clinical efficacy of prepared drugs, UV spectrophotometry is adopted for determination of drug loading capacity of prepared drugs, transmission electron microscopy is adopted to observe the appearance, dynamic dialysis method is used to observe in vitro drug release of prepared drugs and fitting of various release models is done. Anti-tumor effect is studied via level of animal pharmacodynamics. After the end of the experiment, tumor inhibition rate, spleen index and thymus index of drugs are calculated. Experimental results show that the prepared drugs are qualified in terms of regular shape, dispersion, drug content, etc. Animal pharmacodynamics experiments have shown that concentration level of drug loading capacity of prepared drugs has a direct impact on anti-tumor rate. The higher the concentration, the higher the anti-tumor rate. Results of pathological tissue sections of mice show that the prepared drugs cause varying degrees of damage to receptor cells, resulting in cell necrosis or apoptosis problem. It can thus be concluded that ion gel method is an effective method to prepare drug-loading nanoparticles, with prepared nanoparticles evenly distributed in regular shape which demonstrate good slow-release characteristics in receptor vitro and vivo. At the same time, after completion of drug preparation, relatively strong anti-tumor activity can be generated for the receptor, so this mode of preparation enjoys broad

  10. Antitumor effects and mechanisms of Ganoderma extracts and spores oil.

    Science.gov (United States)

    Chen, Chun; Li, Peng; Li, Ye; Yao, Guan; Xu, Jian-Hua

    2016-11-01

    Ganoderma lucidum is a popular herbal medicine used in China to promote health. Modern studies have disclosed that the active ingredients of Ganoderma can exhibit several effects, including antitumor effects and immunomodulation. The present study evaluated the antitumor effects of self-prepared Ganoderma extracts and spores oil, and investigated the possible underlying mechanisms by observing the effects of the extracts and oil on topoisomerases and the cell cycle. The results showed that Ganoderma extracts and spores oil presented dose-dependent inhibitory effects on tumor cells. The half maximal inhibitory concentration (IC 50 ) values of Ganoderma extracts on HL60, K562 and SGC-7901 cells for 24 h were 0.44, 0.39 and 0.90 mg/ml, respectively; for Ganoderma spores oil, the IC 50 values were 1.13, 2.27 and 6.29 mg/ml, respectively. In the in vivo study, the inhibitory rates of Ganoderma extracts (4 g/kg/d, intragastrically) on S180 and H22 cells were 39.1 and 44.6%, respectively, and for Ganoderma spores oil (1.2 g/kg/d, intragastrically) the inhibitory rates were 30.9 and 44.9%, respectively. Ganoderma extracts and spores oil inhibited the activities of topoisomerase I and II. Ganoderma spores oil was shown block the cell cycle at the transition between the G1 and S phases and induce a marked decrease in cyclin D1 levels in K562 cells, with no significant change in cyclin E level. These results suggest that the Ganoderma extracts and spores oil possessed antitumor effects in the in vitro and in vivo studies. The antitumor mechanisms of the extracts and spores oil were associated with inhibitory effects on topoisomerase I and II activities, and for Ganoderma spores oil, the antitumor effects may also be associated with decreased cyclin D1 levels, thus inducing G1 arrest in the cell cycle.

  11. Heterologous expression of MlcE in Saccharomyces cerevisiae provides resistance to natural and semi-synthetic statins

    Directory of Open Access Journals (Sweden)

    Ana Ley

    2015-12-01

    Full Text Available Statins are inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A reductase, the key enzyme in cholesterol biosynthesis. Their extensive use in treatment and prevention of cardiovascular diseases placed statins among the best selling drugs. Construction of Saccharomyces cerevisiae cell factory for the production of high concentrations of natural statins will require establishment of a non-destructive self-resistance mechanism to overcome the undesirable growth inhibition effects of statins. To establish active export of statins from yeast, and thereby detoxification, we integrated a putative efflux pump-encoding gene mlcE from the mevastatin-producing Penicillium citrinum into the S. cerevisiae genome. The resulting strain showed increased resistance to both natural statins (mevastatin and lovastatin and semi-synthetic statin (simvastatin when compared to the wild type strain. Expression of RFP-tagged mlcE showed that MlcE is localized to the yeast plasma and vacuolar membranes. We provide a possible engineering strategy for improvement of future yeast based production of natural and semi-synthetic statins. Keywords: Polyketide, Statins, Saccharomyces cerevisiae, Transport, Cell factory, Resistance

  12. Zoledronic acid enhances antitumor efficacy of liposomal doxorubicin.

    Science.gov (United States)

    Hattori, Yoshiyuki; Shibuya, Kazuhiko; Kojima, Kaori; Miatmoko, Andang; Kawano, Kumi; Ozaki, Kei-Ichi; Yonemochi, Etsuo

    2015-07-01

    Previously, we found that the injection of zoledronic acid (ZOL) into mice bearing tumor induced changes of the vascular structure in the tumor. In this study, we examined whether ZOL treatment could decrease interstitial fluid pressure (IFP) via change of tumor vasculature, and enhance the antitumor efficacy of liposomal doxorubicin (Doxil®). When ZOL solution was injected at 40 µg/mouse per day for three consecutive days into mice bearing murine Lewis lung carcinoma LLC tumor, depletion of macrophages in tumor tissue and decreased density of tumor vasculature were observed. Furthermore, ZOL treatments induced inflammatory cytokines such as interleukin (IL)-10 and -12, granulocyte-macrophage colony-stimulating factor (GM-CSF) and tumor necrosis factor (TNF)-α in serum of LLC tumor-bearing mice, but not in normal mice, indicating that ZOL treatments might induce an inflammatory response in tumor tissue. Furthermore, ZOL treatments increased antitumor activity by Doxil in mice bearing a subcutaneous LLC tumor, although they did not significantly increase the tumor accumulation of doxorubicin (DXR). These results suggest that ZOL treatments might increase the therapeutic efficacy of Doxil via improvement of DXR distribution in a tumor by changing the tumor vasculature. ZOL treatment can be an alternative approach to increase the antitumor effect of liposomal drugs.

  13. Determination of resistance to salt crystallization on natural stone measured with ultrasonic wave

    DEFF Research Database (Denmark)

    Alm, D.; Brix, S.; Kjærgaard, H. Howe

    2008-01-01

    and after salt exposure. Four different stones are investigated: the limestone Bateig Azul, the sandstone Oberkirchener, the limestone Perlatino, and the limestone Travertine. The procedure for the salt crystallization test is EN 12370 standard “Natural stone test methods – Determination of resistance...

  14. TCR-Engineered, Customized, Antitumor T Cells for Cancer Immunotherapy: Advantages and Limitations

    Directory of Open Access Journals (Sweden)

    Arvind Chhabra

    2011-01-01

    Full Text Available The clinical outcome of the traditional adoptive cancer immunotherapy approaches involving the administration of donor-derived immune effectors, expanded ex vivo, has not met expectations. This could be attributed, in part, to the lack of sufficient high-avidity antitumor T-cell precursors in most cancer patients, poor immunogenicity of cancer cells, and the technological limitations to generate a sufficiently large number of tumor antigen-specific T cells. In addition, the host immune regulatory mechanisms and immune homeostasis mechanisms, such as activation-induced cell death (AICD, could further limit the clinical efficacy of the adoptively administered antitumor T cells. Since generation of a sufficiently large number of potent antitumor immune effectors for adoptive administration is critical for the clinical success of this approach, recent advances towards generating customized donor-specific antitumor-effector T cells by engrafting human peripheral blood-derived T cells with a tumor-associated antigen-specific transgenic T-cell receptor (TCR are quite interesting. This manuscript provides a brief overview of the TCR engineering-based cancer immunotherapy approach, its advantages, and the current limitations.

  15. TCR-engineered, customized, antitumor T cells for cancer immunotherapy: advantages and limitations.

    Science.gov (United States)

    Chhabra, Arvind

    2011-01-05

    The clinical outcome of the traditional adoptive cancer immunotherapy approaches involving the administration of donor-derived immune effectors, expanded ex vivo, has not met expectations. This could be attributed, in part, to the lack of sufficient high-avidity antitumor T-cell precursors in most cancer patients, poor immunogenicity of cancer cells, and the technological limitations to generate a sufficiently large number of tumor antigen-specific T cells. In addition, the host immune regulatory mechanisms and immune homeostasis mechanisms, such as activation-induced cell death (AICD), could further limit the clinical efficacy of the adoptively administered antitumor T cells. Since generation of a sufficiently large number of potent antitumor immune effectors for adoptive administration is critical for the clinical success of this approach, recent advances towards generating customized donor-specific antitumor-effector T cells by engrafting human peripheral blood-derived T cells with a tumor-associated antigen-specific transgenic T-cell receptor (TCR) are quite interesting. This manuscript provides a brief overview of the TCR engineering-based cancer immunotherapy approach, its advantages, and the current limitations.

  16. A Single Domain–Based Anti-Her2 Antibody Has Potent Antitumor Activities

    Directory of Open Access Journals (Sweden)

    Xiaoqiong Wu

    2018-04-01

    Full Text Available Human epidermal growth factor receptor 2 (HER2 is overexpressed in approximately 20% to 30% of breast cancers and various other types of cancers, which plays a vital role in the cancer progression. Monoclonal antibodies targeting Her2 are now used in the clinic to treat Her2 overexpression cancer patients. However, relapse or resistance is frequent with the current therapies. To generate a new treatment avenue against Her2, we immunized and selected a specific anti-Her2 single domain antibody C3 for further studies. The C3-Fc antibody drove antibody-dependent cell-mediated cytotoxicity against Her2-positive tumor cells in vitro and resulted in potent antitumor growth in vivo. These data suggest that the C3-Fc antibody may provide an alternative avenue for Her2-positive cancer therapy.

  17. Natural infection of guinea pigs exposed to patients with highly drug-resistant tuberculosis

    Science.gov (United States)

    Dharmadhikari, Ashwin S.; Basaraba, Randall J.; Van Der Walt, Martie L.; Weyer, Karin; Mphahlele, Matsie; Venter, Kobus; Jensen, Paul A.; First, Melvin W.; Parsons, Sydney; McMurray, David N.; Orme, Ian M.; Nardell, Edward A.

    2012-01-01

    A natural TB infection model using guinea pigs may provide useful information for investigating differences in transmission efficiency and establishment of active disease by clinical TB strains in a highly susceptible host under controlled environmental conditions. We sought to examine the capacity of naturally transmitted multidrug-resistant M. tuberculosis to establish infection and produce active disease in guinea pigs. Guinea pigs were continuously exposed for 4 months to the exhaust air of a 6-bed multidrug-resistant tuberculosis inpatient hospital ward in South Africa. Serial tuberculin skin test reactions were measured to determine infection. All animals were subsequently evaluated for histologic disease progression at necropsy. Although 75% of the 362 exposed guinea pigs had positive skin test reactions [≥6mm], only 12% had histopathologic evidence of active disease. Reversions (≥ 6 mm change) in skin test reactivity were seen in 22% of animals, exclusively among those with reactions of 6 to 13 mm. Only two of 86 guinea pigs with reversion had histological evidence of disease compared to 47% (31/66) of guinea pigs with large, non-reverting reactions. Immunosuppression of half the guinea pigs across all skin test categories did not significantly accelerate disease progression. In guinea pigs that reverted a skin test, a second positive reaction in 27 (33%) of them strongly suggested re-infection due to ongoing exposure. These results show that a large majority of guinea pigs naturally exposed to human-source strains of multidrug-resistant tuberculosis became infected, but that many resolved their infection and a large majority failed to progress to detectable disease. PMID:21478054

  18. ISAba1 and Tn6168 acquisition by natural transformation leads to third-generation cephalosporins resistance in Acinetobacter baumannii.

    Science.gov (United States)

    Domingues, Sara; Rosário, Natasha; Ben Cheikh, Hadhemi; Da Silva, Gabriela Jorge

    2018-05-15

    Acinetobacter baumannii has intrinsic beta-lactamase genes, namely ampC and bla OXA-51 -like, which are only strongly expressed when the ISAba1 insertion sequence is upstream the 5' end of the genes. A second ampC gene has also been identified in some clinical A. baumannii strains. The increased expression of these genes leads to resistance to beta-lactams, including third-generation cephalosporins and/or carbapenems. The aim of this work was to assess the involvement of natural transformation in the transfer of chromosomal ampC-associated mobile elements, and related changes in the resistance profile of recipient cells. Natural transformation assays with the naturally competent A. baumannii A118 clinical isolate as recipient cell and the multidrug resistant A. baumannii Ab51 clinical isolate as the source of donor DNA produced transformants. All tested transformants showed integration of the ISAba1 close to the ampC gene. In two transformants, the ISAba1 was acquired by transposition and inserted between the usual folE and the ampC genes. The remaining transformants acquired the ISAba1 adjacent to a second ampC gene, as part of Tn6168, likely by homologous recombination. Our study demonstrates that natural transformation can contribute to the widespread of beta-lactams resistance, and acquisition of non-resistant determinants can lead to changes in the susceptibility profile of A. baumannii strains. Copyright © 2018 Elsevier B.V. All rights reserved.

  19. R-2HG Exhibits Anti-tumor Activity by Targeting FTO/m6A/MYC/CEBPA Signaling.

    Science.gov (United States)

    Su, Rui; Dong, Lei; Li, Chenying; Nachtergaele, Sigrid; Wunderlich, Mark; Qing, Ying; Deng, Xiaolan; Wang, Yungui; Weng, Xiaocheng; Hu, Chao; Yu, Mengxia; Skibbe, Jennifer; Dai, Qing; Zou, Dongling; Wu, Tong; Yu, Kangkang; Weng, Hengyou; Huang, Huilin; Ferchen, Kyle; Qin, Xi; Zhang, Bin; Qi, Jun; Sasaki, Atsuo T; Plas, David R; Bradner, James E; Wei, Minjie; Marcucci, Guido; Jiang, Xi; Mulloy, James C; Jin, Jie; He, Chuan; Chen, Jianjun

    2018-01-11

    R-2-hydroxyglutarate (R-2HG), produced at high levels by mutant isocitrate dehydrogenase 1/2 (IDH1/2) enzymes, was reported as an oncometabolite. We show here that R-2HG also exerts a broad anti-leukemic activity in vitro and in vivo by inhibiting leukemia cell proliferation/viability and by promoting cell-cycle arrest and apoptosis. Mechanistically, R-2HG inhibits fat mass and obesity-associated protein (FTO) activity, thereby increasing global N 6 -methyladenosine (m 6 A) RNA modification in R-2HG-sensitive leukemia cells, which in turn decreases the stability of MYC/CEBPA transcripts, leading to the suppression of relevant pathways. Ectopically expressed mutant IDH1 and S-2HG recapitulate the effects of R-2HG. High levels of FTO sensitize leukemic cells to R-2HG, whereas hyperactivation of MYC signaling confers resistance that can be reversed by the inhibition of MYC signaling. R-2HG also displays anti-tumor activity in glioma. Collectively, while R-2HG accumulated in IDH1/2 mutant cancers contributes to cancer initiation, our work demonstrates anti-tumor effects of 2HG in inhibiting proliferation/survival of FTO-high cancer cells via targeting FTO/m 6 A/MYC/CEBPA signaling. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Successful Treatment of Nivolumab-Resistant Multiple In-Transit Melanomas with Ipilimumab and Topical Imiquimod

    Directory of Open Access Journals (Sweden)

    Taku Fujimura

    2018-01-01

    Full Text Available Simultaneous or sequential, planned administration of ipilimumab could significantly enhance the antitumor effects of nivolumab in advanced melanoma patients. On the other hand, the efficacy of ipilimumab for nivolumab-resistant advanced melanoma is extremely poor. Therefore, additional supportive therapy for anti-PD-1 antibody therapy-resistant advanced melanoma has been widely investigated. In this report, we describe a case of multiple in-transit melanomas developing in a nivolumab-resistant patient successfully treated with ipilimumab in combination with imiquimod. Our present case suggested a possible therapy for nivolumab-resistant multiple in-transit melanomas using ipilimumab in combination with topical imiquimod.

  1. Host-mediated antitumor effect of DMG, a degraded D-manno-D-glucan from Microellobosporia grisea culture fluid.

    Science.gov (United States)

    Nakajima, H; Hashimoto, S; Nagao, S; Kita, Y; Khono, M; Ogawa, H; Abe, S; Mizuno, D

    1984-03-01

    DMG, a new polysaccharide with a well-characterized structure, isolated from the culture filtrate of an actinomycetes and then degraded by acid treatment, was tested for antitumor activity on allogeneic and syngeneic tumors in mice. In the allogeneic Ehrlich solid tumor system, DMG showed antitumor activity over a wide dose range, its optimal dose being 10-100 mg/kg. The optimal time of DMG administration was 1-2 weeks after tumor inoculation, but DMG was also effective when given before tumor inoculation. DMG was effective when given ip, sc, it (intratumorally) or iv. DMG also had antitumor effects on syngeneic tumors. It rapidly inhibited the growth of MM46 mammary carcinoma, MH134 hepatoma, and Meth A fibrosarcoma, and also inhibited spontaneous pulmonary metastases of B16-BL6 melanoma. However, it had no direct cytocidal action on tumor cells in vitro. Its antitumor activity was much less in athymic nude mice and in mice immunosuppressed by whole-body X-irradiation than in normal hosts.Thus, DMG was shown to exert antitumor activity via host-mediated mechanisms. Its antitumor activity is discussed in comparison with those of other antitumor polysaccharides.

  2. Antitumor effects of traditional Chinese medicine targeting the cellular apoptotic pathway

    Directory of Open Access Journals (Sweden)

    Xu HL

    2015-05-01

    Full Text Available Huanli Xu,1 Xin Zhao,2 Xiaohui Liu,1 Pingxiang Xu,1 Keming Zhang,2 Xiukun Lin11Department of Pharmacology, School of Basic Medical Sciences, Capital Medical University, 2Department of Hepatobiliary Surgery, 302 Hospital of Chinese People’s Liberation Army, Beijing, People’s Republic of ChinaAbstract: Defects in apoptosis are common phenomena in many types of cancer and are also a critical step in tumorigenesis. Targeting the apoptotic pathway has been considered an intriguing strategy for cancer therapy. Traditional Chinese medicine (TCM has been used in the People’s Republic of China for thousands of years, and many of the medicines have been confirmed to be effective in the treatment of a number of tumors. With increasing cancer rates worldwide, the antitumor effects of TCMs have attracted more and more attention globally. Many of the TCMs have been shown to have antitumor activity through multiple targets, and apoptosis pathway-related targets have been extensively studied and defined to be promising. This review focuses on several antitumor TCMs, especially those with clinical efficacy, based on their effects on the apoptotic signaling pathway. The problems with and prospects of development of TCMs as anticancer agents are also presented.Keywords: traditional Chinese medicine, antitumor effects, apoptotic pathway

  3. Resistência natural de nove madeiras do semiárido brasileiro a fungos xilófagos em simulares de campo Natural resistance of nine woods from the Brazilian semi-arid region to wood-destroying fungi in field simulators

    Directory of Open Access Journals (Sweden)

    Juarez Benigno Paes

    2009-06-01

    Full Text Available Os objetivos desta pesquisa foram avaliar a resistência de nove madeiras de ocorrência no semiárido brasileiro a fungos xilófagos em simuladores de campo e relacionar a resistência natural com a densidade e teor de substâncias extraídas em água quente. As madeiras estudadas foram algaroba (Prosopis juliflora, angico-vermelho (Anadenanthera colubrina var. cebil, aroeira (Myracrodruon urundeuva, braúna (Schinopsis brasiliensis, cássia (Senna siamea, craibeira (Tabebuia aurea, cumaru (Amburana cearensis, pau-d'arco (Tabebuia impetiginosa e pereiro (Aspidosperma pyrifolium. De cada espécie foram retirados corpos-de-prova de 0,5 x 1,5 x 15,0 cm, com a maior dimensão na direção das fibras, em quatro posições na direção medula-casca do tronco. As amostras permaneceram por 180 dias sob ação da microflora natural existente em três tipos de solos: de floresta, de uso agrícola e com gramíneas. Em todas as madeiras ensaiadas, a resistência ao apodrecimento foi afetada pela posição na direção medula-casca. Apenas na aroeira a resistência da madeira esteve associada à sua densidade e à quantidade de extrativos solúveis em água quente. A resistência das madeiras de algaroba, angico, craibeira e pau-d'arco não esteve associada à densidade nem ao teor de extrativos. O alburno foi a posição mais atacada em todos os solos analisados. Entre os solos testados, o de uso agrícola apresentou menos atividade biológica, deteriorando menos as madeiras testadas.The objectives of this research were to evaluate the natural resistance of nine woods from the Brazilian semi-arid region to fungi under field simulator condition and to correlate the wood natural resistance with the wood density and the content of extractives soluble in hot water. The studied woods were Prosopis juliflora, Anadenanthera colubrina var. cebil, Myracrodruon urundeuva, Schinopsis brasiliensis, Senna siamea, Tabebuia aurea, Amburana cearensis, Tabebuia

  4. Studies on anti-tumor effect of electromagnetic waves

    International Nuclear Information System (INIS)

    Kadota, Ikuhito; Wakabayashi, Toshio; Ogoshi, Kyoji; Kamijo, Akemi

    1995-01-01

    Hyperthermia have treated cancer with thermal effect of electromagnetic waves for biological systems, but the expected effect is not shown. Also non-thermal effect of electromagnetic waves is out of consideration. If irradiation conditions of electromagnetic waves with non-thermal anti-tumor effect are obtained, we can expect newly spread in cancer therapy. We had in vivo experiments that electromagnetic waves were irradiated to mice. In some irradiation conditions, the non-thermal anti-tumor effect of electromagnetic waves showed. In order to specify the irradiation conditions, we had in vitro experiments. We found that activity ratio of tumor cells which was measured by MTT method depended on irradiation time and power of electromagnetic waves. These results are useful for the cancer therapy. (author)

  5. Prediction of Corrosion Resistance of Concrete Containing Natural Pozzolan from Compressive Strength

    Science.gov (United States)

    al-Swaidani, A. M.; Ismat, R.; Diyab, M. E.; Aliyan, S. D.

    2015-11-01

    A lot of Reinforced Concrete (RC) structures in Syria have suffered from reinforcement corrosion which shortened significantly their service lives. Probably, one of the most effective approaches to make concrete structures more durable and concrete industry on the whole - more sustainable is to substitute pozzolan for a portion of Portland cement (PC). Syria is relatively rich in natural pozzolan. In the study, in order to predict the corrosion resistance from compressive strength, concrete specimens were produced with seven cement types: one plain Portland cement (control) and six natural pozzolan-based cements with replacement levels ranging from 10 to 35%. The development of the compressive strengths of concrete cube specimens with curing time has been investigated. Chloride penetrability has also been evaluated for all concrete mixes after three curing times of 7, 28 and 90 days. The effect on resistance of concrete against damage caused by corrosion of the embedded reinforcing steel has been investigated using an accelerated corrosion test by impressing a constant anodic potential for 7, 28 and 90 days curing. Test results have been statistically analysed and correlation equations relating compressive strength and corrosion performance have been developed. Significant correlations have been noted between the compressive strength and both rapid chloride penetrability and corrosion initiation times. So, this prediction could be reliable in concrete mix design when using natural pozzolan as cement replacement.

  6. Treatment of a solid tumor using engineered drug-resistant immunocompetent cells and cytotoxic chemotherapy.

    Science.gov (United States)

    Dasgupta, Anindya; Shields, Jordan E; Spencer, H Trent

    2012-07-01

    Multimodal therapy approaches, such as combining chemotherapy agents with cellular immunotherapy, suffers from potential drug-mediated toxicity to immune effector cells. Overcoming such toxic effects of anticancer cellular products is a potential critical barrier to the development of combined therapeutic approaches. We are evaluating an anticancer strategy that focuses on overcoming such a barrier by genetically engineering drug-resistant variants of immunocompetent cells, thereby allowing for the coadministration of cellular therapy with cytotoxic chemotherapy, a method we refer to as drug-resistant immunotherapy (DRI). The strategy relies on the use of cDNA sequences that confer drug resistance and recombinant lentiviral vectors to transfer nucleic acid sequences into immunocompetent cells. In the present study, we evaluated a DRI-based strategy that incorporates the immunocompetent cell line NK-92, which has intrinsic antitumor properties, genetically engineered to be resistant to both temozolomide and trimetrexate. These immune effector cells efficiently lysed neuroblastoma cell lines, which we show are also sensitive to both chemotherapy agents. The antitumor efficacy of the DRI strategy was demonstrated in vivo, whereby neuroblastoma-bearing NOD/SCID/γ-chain knockout (NSG) mice treated with dual drug-resistant NK-92 cell therapy followed by dual cytotoxic chemotherapy showed tumor regression and significantly enhanced survival compared with animals receiving either nonengineered cell-based therapy and chemotherapy, immunotherapy alone, or chemotherapy alone. These data show there is a benefit to using drug-resistant cellular therapy when combined with cytotoxic chemotherapy approaches.

  7. Antitumor activity of doxorubicine-loaded nanoemulsion against ...

    African Journals Online (AJOL)

    Pharmacotherapy Group, Faculty of Pharmacy, University of Benin, Benin City, 300001 Nigeria. All rights ... Keywords: Doxorubicine, Anti-tumor activity, Mean survival time, Heart histology, Nanoemulsion, Lipid profile .... the standard kit methods using fully Automated ..... effects of this new formulation in human patients.

  8. Antitumor Properties of Modified Detonation Nanodiamonds and Sorbed Doxorubicin on the Model of Ehrlich Ascites Carcinoma.

    Science.gov (United States)

    Medvedeva, N N; Zhukov, E L; Inzhevatkin, E V; Bezzabotnov, V E

    2016-01-01

    We studied antitumor properties of modified detonation nanodiamonds loaded with doxorubicin on in vivo model of Ehrlich ascites carcinoma. The type of tumor development and morphological characteristics of the liver, kidneys, and spleen were evaluated in experimental animals. Modified nanodiamonds injected intraperitoneally produced no antitumor effect on Ehrlich carcinoma. However, doxorubicin did not lose antitumor activity after sorption on modified nanodiamonds.

  9. Modification of carcinogenic and antitumor radiation effects (biomedical aspects)

    International Nuclear Information System (INIS)

    Vilenchik, M.M.

    1985-01-01

    In the book the data on modification of carcinogenic radiation effects by physiologicaly active compounds (caffeine, hormones, promoters and others) as well as on potentiation of antitumor radiation effects by means of hyperthermia are systematized. It is shown that as a basis of synergetic (superadditive) carcinogenic or antitumor radiation effects combined with other factor can be the inhibiting effects of the latter on the reparation process of radiation-induced DNA injuries. The results of experimental investigations and the data on quantitative analysis can be used as a theoretical basis for improvement of the ways and means of the prophylaxis of tumor diseases as well as for increasing the efficiency of radiotherapy

  10. Modulation of human multidrug-resistance MDR-1 gene by natural curcuminoids

    Directory of Open Access Journals (Sweden)

    Buddhasukh Duang

    2004-04-01

    Full Text Available Abstract Background Multidrug resistance (MDR is a phenomenon that is often associated with decreased intracellular drug accumulation in patient's tumor cells resulting from enhanced drug efflux. It is related to the overexpression of a membrane protein, P-glycoprotein (Pgp-170, thereby reducing drug cytotoxicity. A variety of studies have tried to find MDR modulators which increase drug accumulation in cancer cells. Methods In this study, natural curcuminoids, pure curcumin, demethoxycurcumin and bisdemethoxycurcumin, isolated from turmeric (Curcuma longa Linn, were compared for their potential ability to modulate the human MDR-1 gene expression in multidrug resistant human cervical carcinoma cell line, KB-V1 by Western blot analysis and RT-PCR. Results Western blot analysis and RT-PCR showed that all the three curcuminoids inhibited MDR-1 gene expression, and bisdemethoxycurcumin produced maximum effect. In additional studies we found that commercial grade curcuminoid (approximately 77% curcumin, 17% demethoxycurcumin and 3% bisdemthoxycurcumin decreased MDR-1 gene expression in a dose dependent manner and had about the same potent inhibitory effect on MDR-1 gene expression as our natural curcuminoid mixtures. Conclusion These results indicate that bisdemethoxycurcumin is the most active of the curcuminoids present in turmeric for modulation of MDR-1 gene. Treatment of drug resistant KB-V1 cells with curcumin increased their sensitivity to vinblastine, which was consistent with a decreased MDR-1 gene product, a P-glycoprotein, on the cell plasma membrane. Although many drugs that prevent the P-glycoprotein function have been reported, this report describes the inhibition of MDR-1 expression by a phytochemical. The modulation of MDR-1 expression may be an attractive target for new chemosensitizing agents.

  11. Modulation of human multidrug-resistance MDR-1 gene by natural curcuminoids

    International Nuclear Information System (INIS)

    Limtrakul, Pornngarm; Anuchapreeda, Songyot; Buddhasukh, Duang

    2004-01-01

    Multidrug resistance (MDR) is a phenomenon that is often associated with decreased intracellular drug accumulation in patient's tumor cells resulting from enhanced drug efflux. It is related to the overexpression of a membrane protein, P-glycoprotein (Pgp-170), thereby reducing drug cytotoxicity. A variety of studies have tried to find MDR modulators which increase drug accumulation in cancer cells. In this study, natural curcuminoids, pure curcumin, demethoxycurcumin and bisdemethoxycurcumin, isolated from turmeric (Curcuma longa Linn), were compared for their potential ability to modulate the human MDR-1 gene expression in multidrug resistant human cervical carcinoma cell line, KB-V1 by Western blot analysis and RT-PCR. Western blot analysis and RT-PCR showed that all the three curcuminoids inhibited MDR-1 gene expression, and bisdemethoxycurcumin produced maximum effect. In additional studies we found that commercial grade curcuminoid (approximately 77% curcumin, 17% demethoxycurcumin and 3% bisdemthoxycurcumin) decreased MDR-1 gene expression in a dose dependent manner and had about the same potent inhibitory effect on MDR-1 gene expression as our natural curcuminoid mixtures. These results indicate that bisdemethoxycurcumin is the most active of the curcuminoids present in turmeric for modulation of MDR-1 gene. Treatment of drug resistant KB-V1 cells with curcumin increased their sensitivity to vinblastine, which was consistent with a decreased MDR-1 gene product, a P-glycoprotein, on the cell plasma membrane. Although many drugs that prevent the P-glycoprotein function have been reported, this report describes the inhibition of MDR-1 expression by a phytochemical. The modulation of MDR-1 expression may be an attractive target for new chemosensitizing agents

  12. Antitumor effects and mechanisms of Ganoderma extracts and spores oil

    Science.gov (United States)

    Chen, Chun; Li, Peng; Li, Ye; Yao, Guan; Xu, Jian-Hua

    2016-01-01

    Ganoderma lucidum is a popular herbal medicine used in China to promote health. Modern studies have disclosed that the active ingredients of Ganoderma can exhibit several effects, including antitumor effects and immunomodulation. The present study evaluated the antitumor effects of self-prepared Ganoderma extracts and spores oil, and investigated the possible underlying mechanisms by observing the effects of the extracts and oil on topoisomerases and the cell cycle. The results showed that Ganoderma extracts and spores oil presented dose-dependent inhibitory effects on tumor cells. The half maximal inhibitory concentration (IC50) values of Ganoderma extracts on HL60, K562 and SGC-7901 cells for 24 h were 0.44, 0.39 and 0.90 mg/ml, respectively; for Ganoderma spores oil, the IC50 values were 1.13, 2.27 and 6.29 mg/ml, respectively. In the in vivo study, the inhibitory rates of Ganoderma extracts (4 g/kg/d, intragastrically) on S180 and H22 cells were 39.1 and 44.6%, respectively, and for Ganoderma spores oil (1.2 g/kg/d, intragastrically) the inhibitory rates were 30.9 and 44.9%, respectively. Ganoderma extracts and spores oil inhibited the activities of topoisomerase I and II. Ganoderma spores oil was shown block the cell cycle at the transition between the G1 and S phases and induce a marked decrease in cyclin D1 levels in K562 cells, with no significant change in cyclin E level. These results suggest that the Ganoderma extracts and spores oil possessed antitumor effects in the in vitro and in vivo studies. The antitumor mechanisms of the extracts and spores oil were associated with inhibitory effects on topoisomerase I and II activities, and for Ganoderma spores oil, the antitumor effects may also be associated with decreased cyclin D1 levels, thus inducing G1 arrest in the cell cycle. PMID:27900038

  13. Effects of Androgen Ablation on Anti-Tumor Immunity

    National Research Council Canada - National Science Library

    Kast, Martin

    2004-01-01

    .... This AA induced autoimmune-like response exerts limited anti-tumor activity in a murine prostate cancer model, but could be synergistic with CTLA-4 blockade that promotes the development of autoreactive T cell...

  14. NATURAL RESISTANCE OF SEVEN WOODS TO XYLOPHOGOUS FUNGI AND TERMITES UNDER LABORATORY CONDITION

    Directory of Open Access Journals (Sweden)

    Juarez Benigno Paes

    2007-06-01

    Full Text Available This research aimed at evaluating the natural resistance of seven woods to xylophogous fungi and subterranean termites under laboratory assay. The studied woods were Leucaena leucocephala, Cordia trichotoma, Mimosa tenuiflora, Croton sonderianus, Mimosa caesalpiniifolia, Azadirachta indica and Tectona grandis. Test samples measuring 2.54 x 2.00 x 1.00 cm (fungi and 2.54 x 2.00 x 0.64 cm (termites, with larger dimensions in fiber direction were obtained in four positions in pith-to-bark direction. The samples were submitted by 98 days to action of Postia placenta and Polyporus fumosus fungi or 28 days to the termite Nasutitermes corniger action. To fungi, the Mimosa tenuiflora and Mimosa caesalpiniifolia woods were the more resistant and those of Azadirachta indica and Croton sonderianus the less resistant. The fungus Postia placenta attacked more severely the tested woods. To termites, the Mimosa tenuiflora, Cordia trichotoma, and Mimosa caesalpiniifolia were the most resistant and the Leucaena leucocephala the less resistant. The coming wood of external section of log were the more attacked. To fungi, there was an inverse relationship between the density and the loss of mass. Already for the termites, there was not relationship between the resistance and the density of the wood.

  15. Design and Syntheses of Novel Fluoroporphyrin-Anthraquinone Complexes as Antitumor Agents.

    Science.gov (United States)

    Yang, Gu-Liang; Zhao, Sheng-Fang; Chen, Nian-You; Li, Shiming

    2016-01-01

    A novel fluoroporphyrin-anthraquinone hybrid with dipeptide link and its metal complexes were synthesized and evaluated for anti-proliferation activity in human cancer cell line HeLa. The preliminary results demonstrated that all the compounds showed moderate to excellent antitumor activities. Among the active compounds, compound 3 which contains fluorinated porphyrin-anthraquinone and zinc ion exhibited the highest potency with IC50 value of 8.83 µM, indicating that it was a promising antitumor candidate.

  16. Antitumor and radiation protection effects of β-1,3-D-glucan extracted from yeast (saccharomyces cerevisiae)

    International Nuclear Information System (INIS)

    Yoshimura, Akinobu; Hasegawa, Takeo; Monzen, Hajime; Takahashi, Tohru

    2003-01-01

    Various natural extracts are manufactured and on sale as health food products, which are raising popular consciousness of being fit, because they are considered effective or suppressible for cancer. In the current experiment, we measured the immunological activity, antitumor effects, and radioprotective effects of β-1,3-D-glucan (Macroglucan) extracted from bread yeast. Macroglucan of 0, 200, 400, and 800 mg/kg were administered intraperitoneally to C3H/HeJ mice, respectively. The antitumor effects of Macroglucan were examined by measuring natural killer (NK) and lymphokine activated killer (LAK) cell activity and tumor volume. Change in weight, survival, and microscopic manifestation of the intestine were evaluated in the C3H/HeJ mice received total body irradiation to measure radioprotective effect of Macroglucan. According to measurements of cellular cytotoxicity, levels of NK and LAK cell activity were significantly higher in the group administered Macroglucan than in the control group. Macroglucan's role in immunological activity was suggested by the observed suppression of tumor growth in the Macroglucan-administered group. That group also experienced suppression of weight loss after irradiation in the experiment for radioprotection, and a consequent increase in the survival rate compared with the control group. Protective effects appeared in photomicrographs of the intestinal cells. These results confirmed Macroglucan's radioprotective effects. These effects may be related to the suppression of infection accompanying immunological activation due to Macroglucan administration, antioxidant activity, and radical scavenging capacity. (author)

  17. Nanovectorized radiotherapy: a new strategy to induce anti-tumor immunity

    International Nuclear Information System (INIS)

    Vanpouille-Box, Claire; Hindré, François

    2012-01-01

    Recent experimental findings show that activation of the host immune system is required for the success of chemo- and radiotherapy. However, clinically apparent tumors have already developed multiple mechanisms to escape anti-tumor immunity. The fact that tumors are able to induce a state of tolerance and immunosuppression is a major obstacle in immunotherapy. Hence, there is an overwhelming need to develop new strategies that overcome this state of immune tolerance and induce an anti-tumor immune response both at primary and metastatic sites. Nanovectorized radiotherapy that combines ionizing radiation and nanodevices, is one strategy that could boost the quality and magnitude of an immune response in a predictable and designable fashion. The potential benefits of this emerging treatment may be based on the unique combination of immunostimulatory properties of nanoparticles with the ability of ionizing radiation to induce immunogenic tumor cell death. In this review, we will discuss available data and propose that the nanovectorized radiotherapy could be a powerful new strategy to induce anti-tumor immunity required for positive patient outcome.

  18. Nanovectorized radiotherapy, a new strategy to induce anti-tumor immunity

    Directory of Open Access Journals (Sweden)

    Claire eVanpouille-Box

    2012-10-01

    Full Text Available Recent experimental findings show that activation of the host immune system is required for the success of chemo- and radio-therapy. However, clinically-apparent tumors have already developed multiple mechanisms to escape anti-tumor immunity. The fact that tumors are able to induce a state of tolerance and immunosuppression is a major obstacle in immunotherapy. Hence, there is an overwhelming need to develop new strategies that overcome this state of immune tolerance and induce an anti-tumor immune response both at primary and metastatic sites. Nanovectorized radiotherapy that combines ionizing radiation and nano-devices, is one strategy that could boost the quality and magnitude of an immune response in a predictable and designable fashion. The potential benefits of this emerging treatment may be based on the unique combination of immuno-stimulatory properties of nanoparticles with the ability of ionizing radiation to induce immunogenic tumor cell death. In this review, we will discuss available data and propose that the nanovectorized radiotherapy could be a powerful new strategy to induce anti-tumor immunity required for positive patient outcome.

  19. A Polymorphism in the Processing Body Component Ge-1 Controls Resistance to a Naturally Occurring Rhabdovirus in Drosophila.

    Directory of Open Access Journals (Sweden)

    Chuan Cao

    2016-01-01

    Full Text Available Hosts encounter an ever-changing array of pathogens, so there is continual selection for novel ways to resist infection. A powerful way to understand how hosts evolve resistance is to identify the genes that cause variation in susceptibility to infection. Using high-resolution genetic mapping we have identified a naturally occurring polymorphism in a gene called Ge-1 that makes Drosophila melanogaster highly resistant to its natural pathogen Drosophila melanogaster sigma virus (DMelSV. By modifying the sequence of the gene in transgenic flies, we identified a 26 amino acid deletion in the serine-rich linker region of Ge-1 that is causing the resistance. Knocking down the expression of the susceptible allele leads to a decrease in viral titre in infected flies, indicating that Ge-1 is an existing restriction factor whose antiviral effects have been increased by the deletion. Ge-1 plays a central role in RNA degradation and the formation of processing bodies (P bodies. A key effector in antiviral immunity, the RNAi induced silencing complex (RISC, localises to P bodies, but we found that Ge-1-based resistance is not dependent on the small interfering RNA (siRNA pathway. However, we found that Decapping protein 1 (DCP1 protects flies against sigma virus. This protein interacts with Ge-1 and commits mRNA for degradation by removing the 5' cap, suggesting that resistance may rely on this RNA degradation pathway. The serine-rich linker domain of Ge-1 has experienced strong selection during the evolution of Drosophila, suggesting that this gene may be under long-term selection by viruses. These findings demonstrate that studying naturally occurring polymorphisms that increase resistance to infections enables us to identify novel forms of antiviral defence, and support a pattern of major effect polymorphisms controlling resistance to viruses in Drosophila.

  20. Prostate Cancer Cell–Stromal Cell Cross-Talk via FGFR1 Mediates Antitumor Activity of Dovitinib in Bone Metastases

    Science.gov (United States)

    Wan, Xinhai; Corn, Paul G.; Yang, Jun; Palanisamy, Nallasivam; Starbuck, Michael W.; Efstathiou, Eleni; Li-Ning Tapia, Elsa M.; Zurita, Amado J.; Aparicio, Ana; Ravoori, Murali K.; Vazquez, Elba S.; Robinson, Dan R.; Wu, Yi-Mi; Cao, Xuhong; Iyer, Matthew K.; McKeehan, Wallace; Kundra, Vikas; Wang, Fen; Troncoso, Patricia; Chinnaiyan, Arul M.; Logothetis, Christopher J.; Navone, Nora M.

    2015-01-01

    Bone is the most common site of prostate cancer (PCa) progression to a therapy-resistant, lethal phenotype. We found that blockade of fibroblast growth factor receptors (FGFRs) with the receptor tyrosine kinase inhibitor dovitinib has clinical activity in a subset of men with castration-resistant PCa and bone metastases. Our integrated analyses suggest that FGF signaling mediates a positive feedback loop between PCa cells and bone cells and that blockade of FGFR1 in osteoblasts partially mediates the antitumor activity of dovitinib by improving bone quality and by blocking PCa cell–bone cell interaction. These findings account for clinical observations such as reductions in lesion size and intensity on bone scans, lymph node size, and tumor-specific symptoms without proportional declines in prostate-specific antigen concentration. Our findings suggest that targeting FGFR has therapeutic activity in advanced PCa and provide direction for the development of therapies with FGFR inhibitors. PMID:25186177

  1. Antitumor and immunomodulatory activity of Inonotus obliquus

    Directory of Open Access Journals (Sweden)

    Staniszewska Justyna

    2017-06-01

    Full Text Available The article presents the antitumor and immunomodulatory activity of compounds and extracts from Inonotus obliquus. Polysaccharides isolated from sclerotium have a direct antitumor effect due to protein synthesis inhibition in tumor cells. Polysaccharides derived from the mycelium function by activating the immune system. Due to the limited toxicity of these substances, both extracts as well as isolated and purified chemicals may be a good alternative to current chemotherapy and play a role in cancer prevention. In vitro experiments have shown the inhibition of inflammation with the influence of action of I. obliquus extracts; however, in vivo experiments on animals implanted with tumor cells of different types have shown the activation of the host immune system. This led to decrease in tumor mass and prolonged survival. The immunomodulatory mechanism of action is complex and it seems that stimulation of macrophages and induction of apoptosis in cancer cells is of great importance.

  2. Prostate cancer cell-stromal cell crosstalk via FGFR1 mediates antitumor activity of dovitinib in bone metastases.

    Science.gov (United States)

    Wan, Xinhai; Corn, Paul G; Yang, Jun; Palanisamy, Nallasivam; Starbuck, Michael W; Efstathiou, Eleni; Li Ning Tapia, Elsa M; Tapia, Elsa M Li-Ning; Zurita, Amado J; Aparicio, Ana; Ravoori, Murali K; Vazquez, Elba S; Robinson, Dan R; Wu, Yi-Mi; Cao, Xuhong; Iyer, Matthew K; McKeehan, Wallace; Kundra, Vikas; Wang, Fen; Troncoso, Patricia; Chinnaiyan, Arul M; Logothetis, Christopher J; Navone, Nora M

    2014-09-03

    Bone is the most common site of prostate cancer (PCa) progression to a therapy-resistant, lethal phenotype. We found that blockade of fibroblast growth factor receptors (FGFRs) with the receptor tyrosine kinase inhibitor dovitinib has clinical activity in a subset of men with castration-resistant PCa and bone metastases. Our integrated analyses suggest that FGF signaling mediates a positive feedback loop between PCa cells and bone cells and that blockade of FGFR1 in osteoblasts partially mediates the antitumor activity of dovitinib by improving bone quality and by blocking PCa cell-bone cell interaction. These findings account for clinical observations such as reductions in lesion size and intensity on bone scans, lymph node size, and tumor-specific symptoms without proportional declines in serum prostate-specific antigen concentration. Our findings suggest that targeting FGFR has therapeutic activity in advanced PCa and provide direction for the development of therapies with FGFR inhibitors. Copyright © 2014, American Association for the Advancement of Science.

  3. Antitumor Effects of Palladium-α-Lipoic Acid Complex Formulation as an Adjunct in Radiotherapy.

    Science.gov (United States)

    Veena, Ravindran Kalathil; Ajith, Thekkuttuparambil Ananthanarayanan; Janardhanan, Kainoor Krishnankutty; Antonawich, Francis

    2016-01-01

    Several investigations have been initiated to enhance the antitumor effect of radiation and ameliorate its adverse effects such as reducing blood cell counts and causing DNA damage in normal cells. Compounds that enhance the antitumor activity of radiation without reducing blood cell counts or damaging DNA in normal cells can be of immense use as an adjunct in radiotherapy. We evaluated the antitumor effect of a specific set of minerals, vitamins, and amino acids (Poly-MVA) (2 mL/kg, per os), with and without radiation, against Dalton's lymphoma ascites (DLA) and Ehrlich's ascites carcinoma (EAC) cell lines that were transplanted in a solid-tumor model. Whole-body γ-radiation exposure (2 Gy) was performed using 60Co. Poly-MVA enhanced the antitumor effect of radiation when administered beforehand. Furthermore, Poly-MVA administered once daily for 2 wk, immediately after 4 Gy irradiation, protected DNA damage in peripheral blood. It also rendered protection against the radiation-induced reduction of platelet count. The unique electronic and redox properties of palladium-α-lipoic acid complex in Poly-MVA appear to be responsible for the exhibited effect. The results conclude that the antitumor-enhancing and normal cell-protective effect of Poly-MVA warrants additional studies for its potential clinical application.

  4. Purification and characterization of an antitumor polysaccharide from Portulaca oleracea L.

    Science.gov (United States)

    Shen, Huan; Tang, Guo; Zeng, Guang; Yang, Yongjin; Cai, Xingwei; Li, Dongli; Liu, Hongchen; Zhou, Ningxin

    2013-04-02

    In the present study, we purified a unique polysaccharide component (POP) from Portulaca oleracea and found that it had pronounced anti-tumor effects in vivo model. Tumor weight, immune organ index and T lymphocyte subsets were employed to detect the immunoregulatory and antitumor effects of POP after administration. Hematological and biochemical analyses were also investigated in order to evaluate the toxicological aspects related to POP treatment. POP could significantly inhibit the growth of transplantable sarcoma 180 and potentiate the animal's immune responses including an increase in the number of white blood cell (WBC) and CD4(+) T-lymphocytes, as well as the ratio of CD4(+)/CD8(+). Furthermore the serum aspartate transanimase (AST), alanine transaminase (ALT), urea nitrogen (BUN), and creatinine levels in S180-bearing mice were significantly reversed by POP. Considering all these results, it is suggested that the anti-tumor effect elicited by POP could be associated with its immunostimulating properties. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Design of novel antitumor DNA alkylating agents: the benzacronycine series.

    Science.gov (United States)

    David-Cordonnier, Marie-Hélène; Laine, William; Gaslonde, Thomas; Michel, Sylvie; Tillequin, Francois; Koch, Michel; Léonce, Stéphane; Pierré, Alain; Bailly, Christian

    2004-03-01

    Acronycine, a natural alkaloid originally extracted from the bark of the Australian ash scrub Acronychia baueri, has shown a significant antitumor activity in animal models. Acronycine has been tested against human cancers in the early 1980s, but the clinical trials showed modest therapeutic effects and its development was rapidly discontinued. In order to optimize the antineoplastic effect, different benzoacronycine derivatives were synthesized. Among those, the di-acetate compound S23906-1 was recently identified as a promising anticancer drug candidate and a novel alkylating agent specifically reacting with the exocylic 2-NH2 group of guanines in DNA. The study of DNA bonding capacity of acronycine derivatives leads to the identification of the structural requirements for DNA alkylation. In nearly all cases, the potent alkylating agents, such as S23906-1, were found to be much more cytotoxic than the unreactive analogs such as acronycine itself or diol derivatives. Alkylation of DNA by the monoacetate derivative S28687-1, which is a highly reactive hydrolysis metabolite of S23906-1, occurs with a marked preference for the N2 position of guanine. Other bionucleophiles can react with S23906-1. The benzacronycine derivatives, which efficiently alkylate DNA, also covalently bind to the tripeptide glutathione (GSH) but not to the oxidized product glutathione disulfide. Here we review the reactivity of S23906-1 and some derivatives toward DNA and GSH. The structure-activity relationships in the benzacronycine series validate the reaction mechanism implicating DNA as the main molecular target. S23906-1 stands as the most promising lead of a medicinal chemistry program aimed at discovering novel antitumor drugs based on the acronycine skeleton.

  6. Treatment resistance in potentially malignant disorders-'Nature' or 'Nurture'…?

    Science.gov (United States)

    Thomson, P J; Goodson, M L; Smith, D R

    2017-11-01

    Contemporary potentially malignant disorder management is based upon provisional histological diagnosis followed by interventional surgery to excise or ablate 'high-risk' mucosal lesions. Although the majority of patients achieve disease-free status post-treatment, others develop further or persistent disease unresponsive to intervention. A detailed, retrospective clinico-pathological review of treatment resistant potentially malignant lesions, from a 590 patient cohort treated by CO 2 laser surgery and followed for a mean of 7.3 years, was undertaken. Clinical outcome was determined at study census date (31 December 2014). A total of 87 patients (15%) exhibited PMD disease resistant to treatment: 34 (6%) became disease free following further treatment, whilst 53 (9%) had persistent disease despite intervention. Disease-free patients were younger, changed lesion appearance from erythroleukoplakia to leukoplakia (P = .004), developed further lesions at new sites, demonstrated reduction in dysplasia severity with time and required multiple treatments to achieve disease-free status (P = .0005). In contrast, persistent disease patients were older, male, often presented with proliferative verrucous leukoplakia (PVL) on gingival and alveolar sites, displayed less severe dysplasia initially and underwent laser ablation rather than excision (P = .027). Despite clinico-pathological profiling of treatment resistant patients, the precise inter-relationship between the inherent nature of potentially malignant disease and the external influence of treatment intervention remains obscure. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  7. The anti-tumor effect of ACNU and x-irradiation on mouse glioma

    International Nuclear Information System (INIS)

    Nakagawa, Hidemitsu; Hori, Masaharu; Hasegawa, Hiroshi; Mogami, Heitaro; Hayakawa, Toru.

    1979-01-01

    Anti-tumor activities of 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-(2-chloroethyl)-3-nitrosourea hydrochloride (ACNU) and x-irradiation on methylcholanthrene induced glioma in C 57 BL mice were studied in vitro and in vivo. In vitro experiments using cultured glioma cells (MGB cells), the synchronization of cell cycle was done by excess addition of thymidine, and the anti-tumor cell effect were investigated by mean of determinations of DNA synthesis, mitotic index and the number of the living cells following the treatments. As the results, it appeared obvious that ACNU was most effective on MGB cells in S phase and x-irradiation in M phase. As to the combined therapy of ACNU and x-irradiation, the anti-tumor effect was most remarkable when the cells were treated by x-irradiation in the G 2 , M phase, which were hervested by addition of ACNU 44 hours before irradiation. However simultaneous treatment of ACNU and x-irradiation on the cells in G 1 phase was not so remarkable. In vivo experiments the anti-tumor effect of ACNU and x-irradiation on subcutaneously or intracranially transplanted glioma in mice was investigated. Either ACNU 10 mg/kg or local x-irradiation 1240 rads showed inhibitory effect on the tumor growth and prolonged the survival time of the tumor bearing mice. The combination therapy was more effective than ACNU or x-irradiation alone, particularly combination therapy of ACNU and repeated small doses irradiation of x-ray was remarkably effective. Evidence obtained indicated that the combination therapy of ACNU and x-irradiation have synergistic anti-tumor effect on experimental mouse glioma. (author)

  8. Farnesyl diphosphate synthase is involved in the resistance to zoledronic acid of osteosarcoma cells. : resistance of osteosarcoma to nitrogen bisphosphonates

    OpenAIRE

    Ory , Benjamin; Moriceau , Gatien; Trichet , Valérie; Blanchard , Frédéric; Berreur , Martine; Rédini , Françoise; Rogers , Michael; Heymann , Dominique

    2008-01-01

    International audience; We recently demonstrated original anti-tumor effects of zoledronic acid (Zol) on osteosarcoma cell lines independently of their p53 and Rb status. The present study investigated the potential Zol-resistance acquired by osteosarcoma cells after prolonged treatment. After 12 weeks of culture in the presence of 1 microm Zol, the effects of high doses of Zol (10-100 microm) were compared between the untreated rat (OSRGA, ROS) and human (MG63, SAOS2) osteosarcoma cells and ...

  9. Jungle Honey Enhances Immune Function and Antitumor Activity

    Directory of Open Access Journals (Sweden)

    Miki Fukuda

    2011-01-01

    Full Text Available Jungle honey (JH is collected from timber and blossom by wild honey bees that live in the tropical forest of Nigeria. JH is used as a traditional medicine for colds, skin inflammation and burn wounds as well as general health care. However, the effects of JH on immune functions are not clearly known. Therefore, we investigated the effects of JH on immune functions and antitumor activity in mice. Female C57BL/6 mice were injected with JH (1 mg/mouse/day, seven times intra-peritoneal. After seven injections, peritoneal cells (PC were obtained. Antitumor activity was assessed by growth of Lewis Lung Carcinoma/2 (LL/2 cells. PC numbers were increased in JH-injected mice compared to control mice. In Dot Plot analysis by FACS, a new cell population appeared in JH-injected mice. The percent of Gr-1 surface antigen and the intensity of Gr-1 antigen expression of PC were increased in JH-injected mice. The new cell population was neutrophils. JH possessed chemotactic activity for neutrophils. Tumor incidence and weight were decreased in JH-injected mice. The ratio of reactive oxygen species (ROS producing cells was increased in JH-injected mice. The effective component in JH was fractionized by gel filtration using HPLC and had an approximate molecular weight (MW of 261. These results suggest that neutrophils induced by JH possess potent antitumor activity mediated by ROS and the effective immune component of JH is substrate of MW 261.

  10. Conversion of adipose-derived stem cells into natural killer-like cells with anti-tumor activities in nude mice.

    Directory of Open Access Journals (Sweden)

    Hongxiu Ning

    Full Text Available Efforts to develop peripheral blood-derived nature killer (NK cells into therapeutic products have been hampered by these cells' low abundance and histoincompatibility. On the other hand, derivation of NK-like cells from more abundant cell sources such as embryonic stem cells (ESCs and umbilical cord blood (UCB requires the selection of rare CD34+ cells. Thus, we sought to convert adipose-derived stem cells (ADSCs, which are abundant and natively CD34+, into NK-like cells. When grown in hematopoietic induction medium, ADSCs formed sphere clusters and expressed hematopoietic markers CD34, CD45, and KDR. Further induction in NK cell-specific medium resulted in a population of cells that expressed NK cell marker CD56, and thus termed ADSC-NK. Alternatively, the hematopoietically induced ADSCs were transduced with NK cell-specific transcription factor E4BP4 prior to induction in NK cell-specific medium. This latter population of cells, termed ADSC-NKE, expressed CD56 and additional NK cell markers such as CD16, CD94, CD158, CD314, FasL, and NKp46. ADSC-NKE was as potent as NK leukemia cell NKL in killing breast cancer cell MCF7 and prostate cancer cells DU145, PC3, LnCap, DuPro, C4-2 and CWR22, but exhibited no killing activity toward normal endothelial and smooth muscle cells. In nude mice test ADSC-NKE was able to significantly delay the progression of tumors formed by MCF7 and PC3. When injected into immunocompetent rats, ADSC-NKE was detectable in bone marrow and spleen for at least 5 weeks. Together, these results suggest that ADSCs can be converted into NK-like cells with anti-tumor activities.

  11. Antibody complementarity-determining regions (CDRs can display differential antimicrobial, antiviral and antitumor activities.

    Directory of Open Access Journals (Sweden)

    Luciano Polonelli

    Full Text Available BACKGROUND: Complementarity-determining regions (CDRs are immunoglobulin (Ig hypervariable domains that determine specific antibody (Ab binding. We have shown that synthetic CDR-related peptides and many decapeptides spanning the variable region of a recombinant yeast killer toxin-like antiidiotypic Ab are candidacidal in vitro. An alanine-substituted decapeptide from the variable region of this Ab displayed increased cytotoxicity in vitro and/or therapeutic effects in vivo against various bacteria, fungi, protozoa and viruses. The possibility that isolated CDRs, represented by short synthetic peptides, may display antimicrobial, antiviral and antitumor activities irrespective of Ab specificity for a given antigen is addressed here. METHODOLOGY/PRINCIPAL FINDINGS: CDR-based synthetic peptides of murine and human monoclonal Abs directed to: a a protein epitope of Candida albicans cell wall stress mannoprotein; b a synthetic peptide containing well-characterized B-cell and T-cell epitopes; c a carbohydrate blood group A substance, showed differential inhibitory activities in vitro, ex vivo and/or in vivo against C. albicans, HIV-1 and B16F10-Nex2 melanoma cells, conceivably involving different mechanisms of action. Antitumor activities involved peptide-induced caspase-dependent apoptosis. Engineered peptides, obtained by alanine substitution of Ig CDR sequences, and used as surrogates of natural point mutations, showed further differential increased/unaltered/decreased antimicrobial, antiviral and/or antitumor activities. The inhibitory effects observed were largely independent of the specificity of the native Ab and involved chiefly germline encoded CDR1 and CDR2 of light and heavy chains. CONCLUSIONS/SIGNIFICANCE: The high frequency of bioactive peptides based on CDRs suggests that Ig molecules are sources of an unlimited number of sequences potentially active against infectious agents and tumor cells. The easy production and low cost of small

  12. In Vivo Imaging of Natural Killer Cell Trafficking in Tumors

    NARCIS (Netherlands)

    Galli, Filippo; Rapisarda, Anna Serafina; Stabile, Helena; Malviya, Gaurav; Manni, Isabella; Bonanno, Elena; Piaggio, Giulia; Gismondi, Angela; Santoni, Angela; Signore, Alberto

    2015-01-01

    Natural killer cells (NKs) are important effectors of the innate immune system, with marked antitumor activity. Imaging NK trafficking in vivo may be relevant to following up the efficacy of new therapeutic approaches aiming at increasing tumor-infiltrating NKs (TINKs). The specific aims of present

  13. Hederagenin Induces Apoptosis in Cisplatin-Resistant Head and Neck Cancer Cells by Inhibiting the Nrf2-ARE Antioxidant Pathway.

    Science.gov (United States)

    Kim, Eun Hye; Baek, Seungho; Shin, Daiha; Lee, Jaewang; Roh, Jong-Lyel

    2017-01-01

    Acquired resistance to cisplatin is the most common reason for the failure of cisplatin chemotherapy. Hederagenin, triterpenoids extracted from ivy leaves, exhibits antitumor activity in various types of cancer. However, the therapeutic potential of hederagenin in head and neck cancer (HNC) has remained unclear. Therefore, we examined the effects of hederagenin in cisplatin-resistant HNC cells and characterized its molecular mechanisms of action in this context. We evaluated the effects of hederagenin treatment on cell viability, apoptosis, reactive oxygen species (ROS) production, glutathione levels, mitochondrial membrane potential (Δ Ψ m), and protein and mRNA expression in HNC cells. The antitumor effect of hederagenin in mouse tumor xenograft models was also analyzed. Hederagenin selectively induced cell death in both cisplatin-sensitive and cisplatin-resistant HNC cells by promoting changes in Δ Ψ m and inducing apoptosis. Hederagenin inhibited the Nrf2-antioxidant response element (ARE) pathway and activated p53 in HNC cells, thereby enhancing ROS production and promoting glutathione depletion. These effects were reversed by the antioxidant trolox. Hederagenin activated intrinsic apoptotic pathways via cleaved PARP, cleaved caspase-3, and Bax. The selective inhibitory effects of hederagenin were confirmed in cisplatin-resistant HNC xenograft models. These data suggest that hederagenin induces cell death in resistant HNC cells via the Nrf2-ARE antioxidant pathway.

  14. Piper betle extracts exhibit antitumor activity by augmenting antioxidant potential.

    Science.gov (United States)

    Alam, Badrul; Majumder, Rajib; Akter, Shahina; Lee, Sang-Han

    2015-02-01

    The present study was conducted to evaluate the methanolic extract of Piper betle leaves (MPBL) and its organic fractions with regard to antitumor activity against Ehrlich ascites carcinoma (EAC) in Swiss albino mice and to confirm their antioxidant activities. At 24 h post-intraperitoneal inoculation of tumor cells into mice, extracts were administered at 25, 50 and 100 mg/kg body weight for nine consecutive days. The antitumor effects of the extracts were then assessed according to tumor volume, packed cell count, viable and non-viable tumor cell count, median survival time and increase in life span of EAC-bearing mice. Next, hematological profiles and serum biochemical parameters were calculated, and antioxidant properties were assessed by estimating lipid peroxidation, reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) levels. MPBL and the ethylacetate fraction (EPBL) at a dose of 100 mg/kg induced a significant decrease in tumor volume, packed cell volume and viable cell count and increased the life span of the EAC-bearing mice (PPiper betle extracts exhibit significant antitumor activity, which may be attributed to the augmentation of endogenous antioxidant potential.

  15. Ginsenoside Rh2 enhances the antitumor immunological response of a melanoma mice model.

    Science.gov (United States)

    Wang, Meng; Yan, Shi-Ju; Zhang, Hong-Tao; Li, Nan; Liu, Tao; Zhang, Ying-Long; Li, Xiao-Xiang; Ma, Qiong; Qiu, Xiu-Chun; Fan, Qing-Yu; Ma, Bao-An

    2017-02-01

    The treatment of malignant tumors following surgery is important in preventing relapse. Among all the post-surgery treatments, immunomodulators have demonstrated satisfactory effects on preventing recurrence according to recent studies. Ginsenoside is a compound isolated from panax ginseng, which is a famous traditional Chinese medicine. Ginsenoside aids in killing tumor cells through numerous processes, including the antitumor processes of ginsenoside Rh2 and Rg1, and also affects the inflammatory processes of the immune system. However, the role that ginsenoside serves in antitumor immunological activity remains to be elucidated. Therefore, the present study aimed to analyze the effect of ginsenoside Rh2 on the antitumor immunological response. With a melanoma mice model, ginsenoside Rh2 was demonstrated to inhibit tumor growth and improved the survival time of the mice. Ginsenoside Rh2 enhanced T-lymphocyte infiltration in the tumor and triggered cytotoxicity in spleen lymphocytes. In addition, the immunological response triggered by ginsenoside Rh2 could be transferred to other mice. In conclusion, the present study provides evidence that ginsenoside Rh2 treatment enhanced the antitumor immunological response, which may be a potential therapy for melanoma.

  16. Effect of methylxanthines derived from pentoxifylline on P-glycoprotein mediated multidrug resistance

    International Nuclear Information System (INIS)

    Kupsakova, I.; Drobna, Z.; Breier, A.

    2001-01-01

    In this paper study of multidrug resistance (MDR) antitumor agents - P-glycoprotein (PGP) is presented. The ability of pentoxifylline (PTX) to depress resistance mediated by overexpression of PGP in mouse leukemic cell line L 121 ONCR resistant to vincristine (VCR) was described earlier. PTX depressed the resistance of these cells in a dose and time dependent manner. This effect was accompanied by increased level of [ 3 H]-vincristine accumulation by these cells. The methylxanthines with different length of this aliphatic side chain were synthesized and their capability to depress MDR was tested. The results indicated that the position of carbonyl group plays a crucial role for the ability of the derivative to depress MDR of L 121 ONCR cells. (authors)

  17. The anti-tumor histone deacetylase inhibitor SAHA and the natural flavonoid curcumin exhibit synergistic neuroprotection against amyloid-beta toxicity.

    Directory of Open Access Journals (Sweden)

    Jia Meng

    Full Text Available With the trend of an increasing aged population worldwide, Alzheimer's disease (AD, an age-related neurodegenerative disorder, as one of the major causes of dementia in elderly people is of growing concern. Despite the many hard efforts attempted during the past several decades in trying to elucidate the pathological mechanisms underlying AD and putting forward potential therapeutic strategies, there is still a lack of effective treatments for AD. The efficacy of many potential therapeutic drugs for AD is of main concern in clinical practice. For example, large bodies of evidence show that the anti-tumor histone deacetylase (HDAC inhibitor, suberoylanilidehydroxamic acid (SAHA, may be of benefit for the treatment of AD; however, its extensive inhibition of HDACs makes it a poor therapeutic. Moreover, the natural flavonoid, curcumin, may also have a potential therapeutic benefit against AD; however, it is plagued by low bioavailability. Therefore, the integrative effects of SAHA and curcumin were investigated as a protection against amyloid-beta neurotoxicity in vitro. We hypothesized that at low doses their synergistic effect would improve therapeutic selectivity, based on experiments that showed that at low concentrations SAHA and curcumin could provide comprehensive protection against Aβ25-35-induced neuronal damage in PC12 cells, strongly implying potent synergism. Furthermore, network analysis suggested that the possible mechanism underlying their synergistic action might be derived from restoration of the damaged functional link between Akt and the CBP/p300 pathway, which plays a crucial role in the pathological development of AD. Thus, our findings provided a feasible avenue for the application of a synergistic drug combination, SAHA and curcumin, in the treatment of AD.

  18. Antioxidative and antitumor properties of in vitro-cultivated broccoli (Brassica oleracea var. italica).

    Science.gov (United States)

    Cakar, Jasmina; Parić, Adisa; Maksimović, Milka; Bajrović, Kasim

    2012-02-01

    Broccoli [Brassica oleracea L. var. italica Plenck. (Brassicaceae)] contains substantial quantities of bioactive compounds, which are good free radical scavengers and thus might have strong antitumor properties. Enhancing production of plant secondary metabolites could be obtained with phytohormones that have significant effects on the metabolism of secondary metabolites. In that manner, in vitro culture presents good model for manipulation with plant tissues in order to affect secondary metabolite production and thus enhance bioactive properties of plants. Estimation of the antioxidative and antitumor properties of broccoli cultivated in different in vitro conditions. In vitro germinated and cultivated broccoli seedlings, as well as spontaneously developed calli, were subjected to Soxhlet extraction. Antioxidative activity of the herbal extracts was determined using 1,1-diphenyl-2-picrylhydrazyl (DPPH(•)) radical method. Antitumor properties of the extracts were determined using crown-gall tumor inhibition (potato disc) assay. Three, 10, 20, and 30 days old broccoli seedlings, cultivated in vitro on three different Murashige-Skoog media, two types of callus, and seedlings from sterile filter paper were used for extraction. In total, 15 aqueous extracts were tested for antioxidative and antitumor potential. Three day-old seedlings showed the highest antioxidative activity. Eleven out of 15 aqueous extracts demonstrated above 50% of crown-gall tumor inhibition in comparison with the control. Tumor inhibition was in association with types and concentrations of phytohormones presented in growing media. It is demonstrated that phytohormones in plant-growing media could affect the bioactive properties of broccoli either through increasing or decreasing their antioxidative and antitumor potential.

  19. Translocation of integron-associated resistance in a natural system: Acquisition of resistance determinants by Inc P and Inc W Plasmids from Salmonella enterica Typhimurium DT104

    DEFF Research Database (Denmark)

    Sandvang, Dorthe; Diggle, M.; Platt, D.J.

    2002-01-01

    to determinate the genetic content. Translocation to R751 and R388 was associated with the loss of the indigenous trimethoprim cassette to both plasmids and also acquisition of sulfonamide resistance by R751 and RP4::Tn7, which indicated movement of the 3' terminus of one or both of the DT104 integrons......Salmonella enterica Typhimurium DT104, 961368, a veterinary field isolate that encodes a chromosomal cluster of resistance genes as well as two integrons, was used to study the mobility of resistance cassettes (aadA2 and pse-1) and nonintegron-associated resistance determinants (chloramphenicol...... and tetracycline). A range of natural plasmids was used as targets for the translocation of resistance. Plasmids that acquired resistance from the DT104 chromosome were segregated by conjugation into Escherichia coli K12. Plasmids R751, R388, and RP4::Tn7 acquired several combinations of resistance determinant...

  20. Quantitative relationships of the harmful effect of ionizing radiation on natural resistance of the organism to various infectious agents

    International Nuclear Information System (INIS)

    Mal'tsev, V.N.; Strel'nikov, V.A.

    1978-01-01

    An analysis of data from the literature and own experimental results shows that there is an inverse linear correlation between the dose of irradiation and natural resistance of the organism to infection with various infectious agents. With increasing doses of irradiation, the irradiated organism is exposed to the greatest risk from the agents of intestinal infections and representatives of normal microflora. These are followed by agents of various diseases of microbial nature. The minimum reduction can be observed in resistance to viruses. (author)

  1. Ecological resistance in urban streams: the role of natural and legacy attributes

    Science.gov (United States)

    Utz, Ryan M.; Hopkins, Kristina G.; Beesley, Leah; Booth, Derek B.; Hawley, Robert J.; Baker, Matthew E.; Freeman, Mary C.; Jones, Krista L.

    2016-01-01

    Urbanization substantially changes the physicochemical and biological characteristics of streams. The trajectory of negative effect is broadly similar around the world, but the nature and magnitude of ecological responses to urban growth differ among locations. Some heterogeneity in response arises from differences in the level of urban development and attributes of urban water management. However, the heterogeneity also may arise from variation in hydrologic, biological, and physicochemical templates that shaped stream ecosystems before urban development. We present a framework to develop hypotheses that predict how natural watershed and channel attributes in the pre-urban-development state may confer ecological resistance to urbanization. We present 6 testable hypotheses that explore the expression of such attributes under our framework: 1) greater water storage capacity mitigates hydrologic regime shifts, 2) coarse substrates and a balance between erosive forces and sediment supply buffer morphological changes, 3) naturally high ionic concentrations and pH pre-adapt biota to water-quality stress, 4) metapopulation connectivity results in retention of species richness, 5) high functional redundancy buffers trophic function from species loss, and 6) landuse history mutes or reverses the expected trajectory of eutrophication. Data from past comparative analyses support these hypotheses, but rigorous testing will require targeted investigations that account for confounding or interacting factors, such as diversity in urban infrastructure attributes. Improved understanding of the susceptibility or resistance of stream ecosystems could substantially strengthen conservation, management, and monitoring efforts in urban streams. We hope that these preliminary, conceptual hypotheses will encourage others to explore these ideas further and generate additional explanations for the heterogeneity observed in urban streams.

  2. Resistência natural de nove madeiras do semi-árido brasileiro a fungos xilófagos em condições de laboratório Natural resistance of nine woods of Brazilian semi-arid region to wood-destroying fungi under laboratory conditions

    Directory of Open Access Journals (Sweden)

    Juarez Benigno Paes

    2004-04-01

    Full Text Available Objetivou-se avaliar a resistência natural de nove madeiras do semi-árido brasileiro a fungos xilófagos, em condições de laboratório. As madeiras estudadas foram a algaroba (Prosopis juliflora, o angico (Anadenanthera macrocarpa, a aroeira (Myracrodruon urundeuva, a braúna (Schinopsis brasiliensis, a cássia (Senna siamea, a craibeira (Tabebuia aurea, o cumaru (Amburana cearensis, o ipê (Tabebuia impetiginosa e o pereiro (Aspidosperma pyrifolium. De cada espécie foram retirados corpos-de-prova de 2,54 x 2,00 x 1,00 cm, com a maior dimensão na direção das fibras, em quatro posições na direção medula-casca. As amostras foram submetidas, por 14 semanas, à ação dos fungos Postia placenta e Neolentinus lepideus. A resistência natural, com exceção da algaroba e do angico (P. placenta, da craibeira (N. lepideus e da cássia (P. placenta e N. lepideus, foi afetada pela posição na direção medula-casca, sem estar relacionada à densidade das madeiras ensaiadas. A madeira de ipê e a madeira de cerne da aroeira e braúna foram as mais resistentes aos fungos testados. As diferenças entre a resistência natural, exceto para a aroeira e braúna, não estavam associadas à concentração de extrativos solúveis em água quente.The objective of this research was to evaluate the natural resistance of nine semi arid region Brazilian woods to wood-destroying fungi under laboratory conditions. The studied woods were the Prosopis juliflora, Anadenanthera macrocarpa, Myracrodruon urundeuva, Schinopsis brasiliensis, Senna siamea, Tabebuia aurea, Amburana cearensis, Tabebuia impetiginosa and Aspidosperma pyrifolium. Test samples measuring 2.54 x 2.00 x 1.00 cm, with the largest measure taken fiber-wise were obtained from four pith-to-bark positions. The samples were submitted to action of the Postia placenta and Neolentinus lepideus fungi for 14 weeks. Species resistance, with exception of those of Prosopis juliflora and Anadenanthera

  3. Intermittent Metronomic Drug Schedule Is Essential for Activating Antitumor Innate Immunity and Tumor Xenograft Regression

    Directory of Open Access Journals (Sweden)

    Chong-Sheng Chen

    2014-01-01

    Full Text Available Metronomic chemotherapy using cyclophosphamide (CPA is widely associated with antiangiogenesis; however, recent studies implicate other immune-based mechanisms, including antitumor innate immunity, which can induce major tumor regression in implanted brain tumor models. This study demonstrates the critical importance of drug schedule: CPA induced a potent antitumor innate immune response and tumor regression when administered intermittently on a 6-day repeating metronomic schedule but not with the same total exposure to activated CPA administered on an every 3-day schedule or using a daily oral regimen that serves as the basis for many clinical trials of metronomic chemotherapy. Notably, the more frequent metronomic CPA schedules abrogated the antitumor innate immune and therapeutic responses. Further, the innate immune response and antitumor activity both displayed an unusually steep dose-response curve and were not accompanied by antiangiogenesis. The strong recruitment of innate immune cells by the 6-day repeating CPA schedule was not sustained, and tumor regression was abolished, by a moderate (25% reduction in CPA dose. Moreover, an ~20% increase in CPA dose eliminated the partial tumor regression and weak innate immune cell recruitment seen in a subset of the every 6-day treated tumors. Thus, metronomic drug treatment must be at a sufficiently high dose but also sufficiently well spaced in time to induce strong sustained antitumor immune cell recruitment. Many current clinical metronomic chemotherapeutic protocols employ oral daily low-dose schedules that do not meet these requirements, suggesting that they may benefit from optimization designed to maximize antitumor immune responses.

  4. In Vitro and In Vivo Antitumor Activity of [Pt(O,O'-acac)(γ-acac)(DMS)] in Malignant Pleural Mesothelioma.

    Science.gov (United States)

    Muscella, Antonella; Vetrugno, Carla; Cossa, Luca Giulio; Antonaci, Giovanna; De Nuccio, Francesco; De Pascali, Sandra Angelica; Fanizzi, Francesco Paolo; Marsigliante, Santo

    2016-01-01

    Malignant pleural mesothelioma (MPM) is an aggressive malignancy highly resistant to chemotherapy. There is an urgent need for effective therapy inasmuch as resistance, intrinsic and acquired, to conventional therapies is common. Among Pt(II) antitumor drugs, [Pt(O,O'-acac)(γ-acac)(DMS)] (Ptac2S) has recently attracted considerable attention due to its strong in vitro and in vivo antiproliferative activity and reduced toxicity. The purpose of this study was to examine the efficacy of Ptac2S treatment in MPM. We employed the ZL55 human mesothelioma cell line in vitro and in a murine xenograft model in vivo, to test the antitumor activity of Ptac2S. Cytotoxicity assays and Western blottings of different apoptosis and survival proteins were thus performed. Ptac2S increases MPM cell death in vitro and in vivo compared with cisplatin. Ptac2S was more efficacious than cisplatin also in inducing apoptosis characterized by: (a) mitochondria depolarization, (b) increase of bax expression and its cytosol-to-mitochondria translocation and decrease of Bcl-2 expression, (c) activation of caspase-7 and -9. Ptac2S activated full-length PKC-δ and generated a PKC-δ fragment. Full-length PKC-δ translocated to the nucleus and membrane, whilst PKC-δ fragment concentrated to mitochondria. Ptac2S was also responsible for the PKC-ε activation that provoked phosphorylation of p38. Both PKC-δ and PKC-ε inhibition (by PKC-siRNA) reduced the apoptotic death of ZL55 cells. Altogether, our results confirm that Ptac2S is a promising therapeutic agent for malignant mesothelioma, providing a solid starting point for its validation as a suitable candidate for further pharmacological testing.

  5. Natural genetic resources of Arabidopsis thaliana reveal a high prevalence and unexpected phenotypic plasticity of RPW8-mediated powdery mildew resistance

    NARCIS (Netherlands)

    Gollner, K.; Schweizer, P.; Bai, Y.; Panstruga, R.

    2008-01-01

    Here, an approach based on natural genetic variation was adopted to analyse powdery mildew resistance in Arabidopsis thaliana. ¿ Accessions resistant to multiple powdery mildew species were crossed with the susceptible Col-0 ecotype and inheritance of resistance was analysed. Histochemical staining

  6. Antitumor activity of Annona squamosa seed oil.

    Science.gov (United States)

    Chen, Yong; Chen, Yayun; Shi, Yeye; Ma, Chengyao; Wang, Xunan; Li, Yue; Miao, Yunjie; Chen, Jianwei; Li, Xiang

    2016-12-04

    Custard apple (Annona squamosa Linn.) is an edible tropical fruit, and its seeds have been used to treat "malignant sore" (cancer) and other usage as insecticide. A comparison of extraction processes, chemical composition analysis and antitumor activity of A. squamosa seed oil (ASO) were investigated. The optimal extraction parameters of ASO were established by comparing percolation, soxhlet, ultrasonic and SFE-CO 2 extraction methods. The chemical composition of fatty acid and content of total annonaceous acetogenins (ACGs) of ASO was investigated by GC-MS and colorimetric assay, and anti-tumor activity of ASO was tested using H 22 xenografts bearing mice. The optimal extraction parameters of ASO were obtained as follows: using soxhlet extraction method with extraction solvent of petroleum ether, temperature of 80°C, and extraction time of 90min. Under these conditions, the yield of ASO was 22.65%. GC-MS analysis results showed that the main chemical compositions of fatty acid of ASO were palmitic acid (9.92%), linoleic acid (20.49%), oleic acid (56.50%) and stearic acid (9.14%). The total ACGs content in ASO was 41.00mg/g. ASO inhibited the growth of H 22 tumor cells in mice with a maximum inhibitory rate of 53.54% by oral administration. Furthermore, it was found that ASO exerted an antitumor effect via decreasing interleukin-6 (IL-6), janus kinase (Jak) and phosphorylated signal transducers and activators of transcription (p-Stat3) expression. The results demonstrated that ASO suppressed the H 22 solid tumor development may due to its main chemical constituents unsaturated fatty acid and ACGs via IL-6/Jak/Stat3 pathway. ASO may be a potential candidate for the treatment of cancer. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  7. Cholesterol negatively regulates IL-9-producing CD8+ T cell differentiation and antitumor activity.

    Science.gov (United States)

    Ma, Xingzhe; Bi, Enguang; Huang, Chunjian; Lu, Yong; Xue, Gang; Guo, Xing; Wang, Aibo; Yang, Maojie; Qian, Jianfei; Dong, Chen; Yi, Qing

    2018-05-09

    CD8 + T cells can be polarized into IL-9-secreting (Tc9) cells. We previously showed that adoptive therapy using tumor-specific Tc9 cells generated stronger antitumor responses in mouse melanoma than classical Tc1 cells. To understand why Tc9 cells exert stronger antitumor responses, we used gene profiling to compare Tc9 and Tc1 cells. Tc9 cells expressed different levels of cholesterol synthesis and efflux genes and possessed significantly lower cholesterol content than Tc1 cells. Unique to Tc9, but not other CD8 + or CD4 + T cell subsets, manipulating cholesterol content in polarizing Tc9 cells significantly affected IL-9 expression and Tc9 differentiation and antitumor response in vivo. Mechanistic studies showed that IL-9 was indispensable for Tc9 cell persistence and antitumor effects, and cholesterol or its derivatives inhibited IL-9 expression by activating liver X receptors (LXRs), leading to LXR Sumoylation and reduced p65 binding to Il9 promoter. Our study identifies cholesterol as a critical regulator of Tc9 cell differentiation and function. © 2018 Ma et al.

  8. Protection by S-2-(3-aminopropylamino)ethylphosphorothioic acid against radiation- and cyclophosphamide-induced attenuation in antitumor resistance

    International Nuclear Information System (INIS)

    Milas, L.; McBride, W.H.; Hunter, N.; Ito, H.

    1984-01-01

    Studies were performed to investigate whether S-2-(3-amino-propylamino)ethylphosphorothioic acid (WR-2721) can protect antitumor immune rejection responses against the damaging effects of whole-body irradiation (WBI) and cyclophosphamide (CY). The ability of WR-2721 to protect against WBI -induced decreased radioresponse of solitary tumors was also investigated. All experiments were performed with an immunogenic fibrosarcoma syngeneic to C3Hf/ Kam mice. WR-2721 was given i.p. at a dose of 400 mg/kg 30 min before WBI with gamma-rays or CY injection. WBI with 650 rads reduced the number of tumor cells needed for tumor take in 50% of animals from 5.1 X 10(4) cells in normal mice to 2.0 X 10(2). WR-2721 given before WBI almost entirely abolished the effect of WBI : the number of tumor cells needed for tumor take in 50% of animals was 1.4 X 10(4). Treatment of mice with WBI or CY increased the number of tumor nodules in the lung generated by fibrosarcoma cells injected i.v. 5 days later, in a linear dose response. WR-2721 greatly reduced this metastasis enhancement effect of WBI and CY with protection factors of 2.5 for WBI and 1.8 for CY. Fibrosarcomas of 8 mm in diameter exhibited a decreased radiocurability when growing in WBI mice: the dose of irradiation yielding local tumor control in 50% of animals in these mice was 5950 compared to a dose of irradiation yielding local tumor control in 50% of animals of 4160 rads in normal mice. WR-2721 given before WBI inhibited this effect of WBI : the dose of irradiation yielding local tumor control in 50% of animals was 5210 rads. The proportion of macrophages in tumors growing in WBI mice was significantly reduced, but not when WR-2721 was first given. WR-2721 greatly reduced the damaging effects of WBI and CY on natural killer cell activity

  9. Crystal Structure of the Zorbamycin-Binding Protein ZbmA, the Primary Self-Resistance Element in Streptomyces flavoviridis ATCC21892

    Energy Technology Data Exchange (ETDEWEB)

    Rudolf, Jeffrey D. [Scripps Research Inst., Jupiter, FL (United States); Bigelow, Lance [Argonne National Lab. (ANL), Argonne, IL (United States); Chang, Changsoo [Argonne National Lab. (ANL), Argonne, IL (United States); Cuff, Marianne E. [Argonne National Lab. (ANL), Argonne, IL (United States); Lohman, Jeremy R. [Scripps Research Inst., Jupiter, FL (United States); Chang, Chin-Yuan [Scripps Research Inst., Jupiter, FL (United States); Ma, Ming [Scripps Research Inst., Jupiter, FL (United States); Yang, Dong [Scripps Research Inst., Jupiter, FL (United States); Clancy, Shonda [Argonne National Lab. (ANL), Argonne, IL (United States); Babnigg, Gyorgy [Argonne National Lab. (ANL), Argonne, IL (United States); Joachimiak, Andrzej [Argonne National Lab. (ANL), Argonne, IL (United States); Phillips, George N. [Rice Univ., Houston, TX (United States); Shen, Ben [Scripps Research Inst., Jupiter, FL (United States)

    2015-11-17

    The bleomycins (BLMs), tallysomycins (TLMs), phleomycin, and zorbamycin (ZBM) are members of the BLM family of glycopeptide-derived antitumor antibiotics. The BLM-producing Streptomyces verticillus ATCC15003 and the TLM-producing Streptoalloteichus hindustanus E465-94 ATCC31158 both possess at least two self-resistance elements, an N-acetyltransferase and a binding protein. The N-acetyltransferase provides resistance by disrupting the metal-binding domain of the antibiotic that is required for activity, while the binding protein confers resistance by sequestering the metal-bound antibiotic and preventing drug activation via molecular oxygen. We recently established that the ZBM producer, Streptomyces flavoviridis ATCC21892, lacks the N-acetyltransferase resistance gene and that the ZBM-binding protein, ZbmA, is sufficient to confer resistance in the producing strain. To investigate the resistance mechanism attributed to ZbmA, we determined the crystal structures of apo and Cu(II)-ZBM-bound ZbmA at high resolutions of 1.90 and 1.65 angstrom, respectively. A comparison and contrast with other structurally characterized members of the BLM-binding protein family revealed key differences in the protein ligand binding environment that fine-tunes the ability of ZbmA to sequester metal-bound ZBM and supports drug sequestration as the primary resistance mechanism in the producing organisms of the BLM family of antitumor antibiotics.

  10. Novel production method of innovative antiangiogenic and antitumor small peptides in Escherichia coli

    Directory of Open Access Journals (Sweden)

    Setrerrahmane S

    2017-11-01

    Full Text Available Sarra Setrerrahmane,1 Jian Yu,1 Jingchao Hao,1,2 Heng Zheng,3 Hanmei Xu1,3 1The Engineering Research Center of Peptide Drug Discovery and Development, China Pharmaceutical University, Nanjing, Jiangsu, 2College of Pharmacy & the Provincial Key Laboratory of Natural Drug and Pharmacology, Kunming, Yunnan, 3State Key Laboratory of Natural Medicines, Ministry of Education, China Pharmaceutical University, Nanjing, Jiangsu, People’s Republic of China Background: Developing innovative drugs with potent efficacy, specificity, and high safety remains an ongoing task in antitumor therapy development. In the last few years, peptide drugs have become attractive agents in cancer therapy. HM-3, mainly with antiangiogenic effect, and AP25, with an additional antiproliferative effect, are two peptides designed in our laboratory targeting αvβ3 and α5β1 integrins, respectively. The low molecular weight of the two peptides renders their recombinant expression very difficult, and the complicated structure of AP25 makes its chemical synthesis restricted, which presents a big challenge for its development.Methods: Bifunctional peptides designed by the ligation of HM-3 and AP25, using linkers with different flexibility, were prepared using recombinant DNA technology in Escherichia coli. The fusion peptides were expressed in a modified auto-induction medium based on a mixture of glucose, glycerol, and lactose as carbon substrates and NH4+ as nitrogen source without any amino acid or other elements. Subsequently, the antiangiogenic, antiproliferative, and cell adhesion assays were conducted to evaluate the bioactivity of the two fusion peptides.Results: The peptides were successfully expressed in a soluble form without any induction, which allows the culture to reach higher cell density before protein expression occurs. Human umbilical vein endothelial cell migration assay and chick embryo chorioallantoic membrane assay showed, at low doses, a significantly

  11. Antitumor effects evaluation of a novel porphyrin derivative in photodynamic therapy.

    Science.gov (United States)

    Li, Jian-Wei; Wu, Zhong-Ming; Magetic, Davor; Zhang, Li-Jun; Chen, Zhi-Long

    2015-12-01

    In this paper, the antitumor activity of a novel porphyrin-based photosensitizer 5,10,15,20-tetrakis[(5-diethylamino)pentyl] porphyrin (TDPP) was reported in vitro and in vivo. The photophysical and cellular properties of TDPP were investigated. The singlet oxygen generation quantum yield of TDPP was detected; it showed a high singlet oxygen quantum yield of 0.52. The intracellular distribution of photosensitizer was detected with laser scanning confocal microscopy. The efficiency of TDPP-photodynamic therapy (PDT) in vitro was analyzed by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay and in situ trypan blue exclusion test. Treated with a 630-nm laser, TDPP can kill cultured human esophageal cancer cell line (Eca-109) cells and reduce the growth of Eca-109 xenograft tumors significantly in BABL/c nude mice. And histopathological study was also used to confirm the antitumor effect. It has the perspective to be developed as a new antitumor drug in photodynamic therapy and deserves further investigation.

  12. Natural coagulation inhibitors and active protein c resistance in preeclampsia

    Directory of Open Access Journals (Sweden)

    Cengiz Demir

    2010-01-01

    Full Text Available INTRODUCTION: The etiology of preeclampsia is not fully established. A few studies have shown a relationship between natural coagulation inhibitors and preeclampsia. OBJECTIVES: The purpose of this study was to investigate the status of natural coagulation inhibitors and active protein C resistance (APC-R in preeclampsia. PATIENTS AND METHODS: We studied 70 women with preeclampsia recruited consecutively and 70 healthy pregnant and 70 nonpregnant women as controls. Plasma protein C (PC, free protein S (fPS, antithrombin III (ATIII and APC-R were evaluated. RESULTS: ATIII values were found to be significantly lower in preeclamptic patients than in the control groups (p< 0.001. Nevertheless, there was no significant difference between the healthy pregnant and nonpregnant women groups (p=0.141. The fPS values of the preeclamptic and healthy pregnant groups were lower than that of the nonpregnant group (p< 0.001, and the fPS value of the preeclamptic pregnant women was lower than that of healthy pregnant women (p<0.001. The PC value of the preeclamptic pregnant women was lower than that of the control groups (p< 0.001. The PC value of the healthy pregnant women was lower than that of the nonpregnant women (p< 0.001. The mean APC activity values were lower in the preeclamptic patients than that of the control groups (p< 0.001, p< 0.001. The APC-R positivity rates of the preeclamptic groups were higher than that of the control groups (p<0.001. CONCLUSIONS: This study demonstrated that ATIII, fPS, PC values and APC resistance were lower and APC-R positivity was higher in preeclamptic women than in normal pregnant and nonpregnant women.

  13. Poly (I:C) enhances the anti-tumor activity of canine parvovirus NS1 protein by inducing a potent anti-tumor immune response.

    Science.gov (United States)

    Gupta, Shishir Kumar; Yadav, Pavan Kumar; Tiwari, A K; Gandham, Ravi Kumar; Sahoo, A P

    2016-09-01

    The canine parvovirus NS1 (CPV2.NS1) protein selectively induces apoptosis in the malignant cells. However, for an effective in vivo tumor treatment strategy, an oncolytic agent also needs to induce a potent anti-tumor immune response. In the present study, we used poly (I:C), a TLR3 ligand, as an adjuvant along with CPV2.NS1 to find out if the combination can enhance the oncolytic activity by inducing a potent anti-tumor immune response. The 4T1 mammary carcinoma cells were used to induce mammary tumor in Balb/c mice. The results suggested that poly (I:C), when given along with CPV2.NS1, not only significantly reduced the tumor growth but also augmented the immune response against tumor antigen(s) as indicated by the increase in blood CD4+ and CD8+ counts and infiltration of immune cells in the tumor tissue. Further, blood serum analysis of the cytokines revealed that Th1 cytokines (IFN-γ and IL-2) were significantly upregulated in the treatment group indicating activation of cell-mediated immune response. The present study reports the efficacy of CPV2.NS1 along with poly (I:C) not only in inhibiting the mammary tumor growth but also in generating an active anti-tumor immune response without any visible toxicity. The results of our study may help in developing CPV2.NS1 and poly (I: C) combination as a cancer therapeutic regime to treat various malignancies.

  14. Novel oral administrated paclitaxel micelles with enhanced bioavailability and antitumor efficacy for resistant breast cancer.

    Science.gov (United States)

    Zhang, Ting; Luo, Jingwen; Fu, Yao; Li, Hanmei; Ding, Rui; Gong, Tao; Zhang, Zhirong

    2017-02-01

    Paclitaxel (PTX) is a widely used antineoplastic drug in clinic. Due to poor aqueous solubility, it is administrated by intravenous infusion of cremophor EL containing formulation with serious adverse effects. The low oral bioavailability is a great challenge for oral formulation development. In addition, P-gp mediated multidrug resistance limit its clinical use in various resistant cancers. In this study, a novel super-antiresistant PTX micelle formulation for oral administration was developed. A P-gp inhibitor, bromotetrandrine (W198) was co-encapsulated in the micelle. The micelles were composed of Solutol HS 15 and d-a-tocopheryl polyethylene glycol succinate to avoid Cremophor EL induced toxicity. The micelles were round with a mean particle size of ∼13nm and an encapsulation efficiency of ∼90%. A series of in vitro evaluations were performed in non-resistant MCF-7 cells and resistant MCF-7/Adr cells. The super-antiresistant PTX micelles showed higher cell uptake efficiency, significantly increased cytotoxicity and antimitotic effect in drug resistant MCF-7/Adr cells when compared with Taxol and other PTX micelle formulations. Compared with Taxol, the super-antiresistant PTX micelles significantly improved bioavailability after oral administration in rats, and inhibited tumor growth in multidrug resistance xenografted MCF-7/Adr nude mice. In summary, the noval super-antiresistant PTX micelles showed a great potential for oral delivery of PTX against resistant breast cancer. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Anti-tumor Activity of Toll-Like Receptor 7 Agonists

    Directory of Open Access Journals (Sweden)

    Huju Chi

    2017-05-01

    Full Text Available Toll-like receptors (TLRs are a class of pattern recognition receptors that play a bridging role in innate immunity and adaptive immunity. The activated TLRs not only induce inflammatory responses, but also elicit the development of antigen specific immunity. TLR7, a member of TLR family, is an intracellular receptor expressed on the membrane of endosomes. TLR7 can be triggered not only by ssRNA during viral infections, but also by immune modifiers that share a similar structure to nucleosides. Its powerful immune stimulatory action can be potentially used in the anti-tumor therapy. This article reviewed the anti-tumor activity and mechanism of TLR7 agonists that are frequently applied in preclinical and clinical investigations, and mainly focused on small synthetic molecules, including imiquimod, resiquimod, gardiquimod, and 852A, etc.

  16. Oncolytic Immunotherapy: Dying the Right Way is a Key to Eliciting Potent Antitumor Immunity

    Directory of Open Access Journals (Sweden)

    Zong Sheng eGuo

    2014-04-01

    Full Text Available Oncolytic viruses (OVs are novel immunotherapeutic agents whose anticancer effects come from both oncolysis and elicited antitumor immunity. OVs induce mostly immunogenic cancer cell death (ICD, including immunogenic apoptosis, necrosis/necroptosis, pyroptosis and autophagic cell death, leading to exposure of calreticulin and heat-shock proteins to the cell surface, and/or released ATP, high mobility group box-1 [HMGB1], uric acid, and other DAMPs as well as PAMPs as danger signals, along with tumor-associated antigens, to activate dendritic cells (DCs and elicit adaptive antitumor immunity. Dying the right way may greatly potentiate adaptive antitumor immunity. The mode of cancer cell death may be modulated by individual OVs and cancer cells as they often encode and express genes that inhibit/promote apoptosis, necroptosis or autophagic cell death. We can genetically engineer OVs with death-pathway-modulating genes and thus skew the infected cancer cells towards certain death pathways for the enhanced immunogenicity. Strategies combining with some standard therapeutic regimens may also change the immunological consequence of cancer cell death. In this review, we discuss recent advances in our understanding of danger signals, modes of cancer cell death induced by OVs, the induced danger signals and functions in eliciting subsequent antitumor immunity. We also discuss potential combination strategies to target cells into specific modes of ICD and enhance cancer immunogenicity, including blockade of immune checkpoints, in order to break immune tolerance, improve antitumor immunity and thus the overall therapeutic efficacy.

  17. Two photon microscopy intravital study of DC-mediated anti-tumor response of NK cells

    Science.gov (United States)

    Caccia, Michele; Gorletta, Tatiana; Sironi, Laura; Zanoni, Ivan; Salvetti, Cristina; Collini, Maddalena; Granucci, Francesca; Chirico, Giuseppe

    2010-02-01

    Recent studies have demonstrated that dendritic cells (DCs) play a crucial role in the activation of Natural Killer cells (NKs) that are responsible for anti-tumor innate immune responses. The focus of this report is on the role of pathogen associated molecular pattern (PAMP) activated-DCs in inducing NK cell-mediated anti-tumor responses. Mice transplanted sub-cute (s.c.) with AK7 cells, a mesothelioma cell line sensitive to NK cell responses, are injected with fluorescent NK cells and DC activation is then induced by s.c. injection of Lipopolysaccharide (LPS). Using 4 dimensional tracking we follow the kinetic behavior of NK cells at the Draining Lymph-Node (DLN). As control, noninflammatory conditions are also evaluated. Our data suggest that NK cells are recruited to the DLN where they can interact with activated-DCs with a peculiar kinetic behavior: short lived interactions interleaved by rarer longer ones. We also found that the changes in the NK dynamic behavior in inflammatory conditions clearly affect relevant motility parameters such as the instantaneous and average velocity and the effective diffusion coefficient. This observation suggests that NK cells and activated-DCs might efficiently interact in the DLN, where cells could be activated. Therefore the interaction between activated-DCs and NK cells in DLN is not only a reality but it may be also crucial for the start of the immune response of the NKs.

  18. Smart Mesoporous Nanomaterials for Antitumor Therapy

    Directory of Open Access Journals (Sweden)

    Marina Martínez-Carmona

    2015-11-01

    Full Text Available The use of nanomaterials for the treatment of solid tumours is receiving increasing attention by the scientific community. Among them, mesoporous silica nanoparticles (MSNs exhibit unique features that make them suitable nanocarriers to host, transport and protect drug molecules until the target is reached. It is possible to incorporate different targeting ligands to the outermost surface of MSNs to selectively drive the drugs to the tumour tissues. To prevent the premature release of the cargo entrapped in the mesopores, it is feasible to cap the pore entrances using stimuli-responsive nanogates. Therefore, upon exposure to internal (pH, enzymes, glutathione, etc. or external (temperature, light, magnetic field, etc. stimuli, the pore opening takes place and the release of the entrapped cargo occurs. These smart MSNs are capable of selectively reaching and accumulating at the target tissue and releasing the entrapped drug in a specific and controlled fashion, constituting a promising alternative to conventional chemotherapy, which is typically associated with undesired side effects. In this review, we overview the recent advances reported by the scientific community in developing MSNs for antitumor therapy. We highlight the possibility to design multifunctional nanosystems using different therapeutic approaches aimed at increasing the efficacy of the antitumor treatment.

  19. PSMA-targeted polyinosine/polycytosine vector induces prostate tumor regression and invokes an antitumor immune response in mice.

    Science.gov (United States)

    Langut, Yael; Talhami, Alaa; Mamidi, Samarasimhareddy; Shir, Alexei; Zigler, Maya; Joubran, Salim; Sagalov, Anna; Flashner-Abramson, Efrat; Edinger, Nufar; Klein, Shoshana; Levitzki, Alexander

    2017-12-26

    There is an urgent need for an effective treatment for metastatic prostate cancer (PC). Prostate tumors invariably overexpress prostate surface membrane antigen (PSMA). We designed a nonviral vector, PEI-PEG-DUPA (PPD), comprising polyethylenimine-polyethyleneglycol (PEI-PEG) tethered to the PSMA ligand, 2-[3-(1, 3-dicarboxy propyl)ureido] pentanedioic acid (DUPA), to treat PC. The purpose of PEI is to bind polyinosinic/polycytosinic acid (polyIC) and allow endosomal release, while DUPA targets PC cells. PolyIC activates multiple pathways that lead to tumor cell death and to the activation of bystander effects that harness the immune system against the tumor, attacking nontargeted neighboring tumor cells and reducing the probability of acquired resistance and disease recurrence. Targeting polyIC directly to tumor cells avoids the toxicity associated with systemic delivery. PPD selectively delivered polyIC into PSMA-overexpressing PC cells, inducing apoptosis, cytokine secretion, and the recruitment of human peripheral blood mononuclear cells (PBMCs). PSMA-overexpressing tumors in nonobese diabetic/severe combined immunodeficiency (NOD/SCID) mice with partially reconstituted immune systems were significantly shrunken following PPD/polyIC treatment, in all cases. Half of the tumors showed complete regression. PPD/polyIC invokes antitumor immunity, but unlike many immunotherapies does not need to be personalized for each patient. The potent antitumor effects of PPD/polyIC should spur its development for clinical use.

  20. Extracellular vesicles as shuttles of tumor biomarkers and anti-tumor drugs.

    Science.gov (United States)

    Zocco, Davide; Ferruzzi, Pietro; Cappello, Francesco; Kuo, Winston Patrick; Fais, Stefano

    2014-01-01

    Extracellular vesicles (EV) include vesicles released by either normal or tumor cells. EV may exceed the nanometric scale (microvesicles), or to be within the nanoscale, also called exosomes. Thus, it appears that only exosomes and larger vesicles may have the size for potential applications in nanomedicine, in either disease diagnosis or therapy. This is of particular interest for research in cancer, also because the vast majority of existing data on EV are coming from pre-clinical and clinical oncology. We know that the microenvironmental features of cancer may favor cell-to-cell paracrine communication through EV, but EV have been purified, characterized, and quantified from plasma of tumor patients as well, thus suggesting that EV may have a role in promoting and maintaining cancer dissemination and progression. These observations are prompting research efforts to evaluate the use of nanovesicles as tumor biomarkers. Moreover, EVs are emerging as natural delivery systems and in particular, exosomes may represent the ideal natural nanoshuttles for new and old anti-tumor drugs. However, much is yet to be understood about the role of EV in oncology and this article aims to discuss the future of EV in cancer on the basis of current knowledge.

  1. Synthesis and antitumor testing of certain new fused triazolopyrimidine and triazoloquinazoline derivatives

    Directory of Open Access Journals (Sweden)

    Ghada S. Hassan

    2017-02-01

    Full Text Available New series of 1,2,4-triazolopyrimidine and 1,2,4-triazoloquinazoline derivatives were designed, synthesized, and evaluated for their antitumor activity. Compounds 6, 11, 26, 29, 41, 44, 48, 49 and 58 were tested as antitumor agents by the use of DNA-binding assay on TLC-plates, colorimetric assay for the degree of DNA-binding (Methyl green-DNA displacement assay, evaluation of antineoplastic activity against Ehrlich Ascites Carcinoma in mice, and finally modulation of apoptosis. 5-Flurouracil, vitamin C and ethidium bromide were used as positive controls in these techniques. Compound 26 proved to be the most active member of these series as antitumor agent with IC50 value of 47 ± 1. Several characteristic features were observed to be essential for activity such as the morpholine group and the phenylazo group, in addition the electron-withdrawing groups favor the activity than the electron-donating ones.

  2. FREEZE-THAW AND FIRE RESISTANCE OF GEOPOLYMER MORTAR BASED ON NATURAL AND WASTE POZZOLANS

    Directory of Open Access Journals (Sweden)

    F.Nurhayat Degirmenci

    2017-12-01

    Full Text Available The purpose of this research was to investigate the resistance of pozzolan-based geopolymer mortars subjected to high temperatures and freeze-thaw cycles. Low calcium fly ash and granulated blast furnace slag as waste pozzolans and natural zeolite as a natural pozzolan were used as base materials for producing geopolymer mortar. The other purpose the research was to study the effect of alkaline activator ratio (Na₂SiO₃/NaOH on the performance of pozzolan-based geopolymer mortar specimens subjected to extreme temperatures. The influence of high temperatures on the properties of mortars was investigated at 300°C, 600°C, and 900°C. Fire and freeze-thaw and resistance of mortars were investigated in terms of visual appearance, weight loss and residual compressive strength. The minimal values of the residual compressive strength were obtained at 900°C for all mixtures. The residual compressive strength of all specimens was lower than the values obtained for specimens not subjected to any freeze-thaw resistance test, except those containing GGBS. The Na₂SiO₃/NaOH ratios of the alkaline activator solution used to prepare the geopolymer mortars have an effect on the weight losses and residual compressive strengths of the specimens subjected to high temperatures and freeze-thaw cycles. As the Na2SiO3/NaOH ratios increased, the weight and strength losses decreased.

  3. Naturally occurring dominant drug resistance mutations occur infrequently in the setting of recently acquired hepatitis C.

    Science.gov (United States)

    Applegate, Tanya L; Gaudieri, Silvana; Plauzolles, Anne; Chopra, Abha; Grebely, Jason; Lucas, Michaela; Hellard, Margaret; Luciani, Fabio; Dore, Gregory J; Matthews, Gail V

    2015-01-01

    Direct-acting antivirals (DAAs) are predicted to transform hepatitis C therapy, yet little is known about the prevalence of naturally occurring resistance mutations in recently acquired HCV. This study aimed to determine the prevalence and frequency of drug resistance mutations in the viral quasispecies among HIV-positive and -negative individuals with recent HCV. The NS3 protease, NS5A and NS5B polymerase genes were amplified from 50 genotype 1a participants of the Australian Trial in Acute Hepatitis C. Amino acid variations at sites known to be associated with possible drug resistance were analysed by ultra-deep pyrosequencing. A total of 12% of individuals harboured dominant resistance mutations, while 36% demonstrated non-dominant resistant variants below that detectable by bulk sequencing (that is, Resistance variants (resistance from all classes, with the exception of sofosbuvir. Dominant resistant mutations were uncommonly observed in the setting of recent HCV. However, low-level mutations to all DAA classes were observed by deep sequencing at the majority of sites and in most individuals. The significance of these variants and impact on future treatment options remains to be determined. Clinicaltrials.gov NCT00192569.

  4. Synthesis of sulfadimethoxine based surfactants and their evaluation as antitumor agents

    Directory of Open Access Journals (Sweden)

    Manal Mohmed Khowdiary

    2016-01-01

    Summary: The main goal of cancer therapy is to attain the maximum therapeutic damage of tumor cells in combination with a minimum concentration of the drug. This can be achieved in principle via selective antitumor preparations, the cytostatic effects of which would be restricted within tumor tissue. While 100% selectivity may be impractical, the achievement of reasonably high selectivity seems to be a feasible aim. Platinum and cobalt complex surfactants in our research affect tumor tissue at a very low concentration at values lower than their CMC values; this indicate that the sulfadimethoxine complexes merit further investigation as potential antitumor drugs.

  5. Natural resistance to experimental feline infectious peritonitis virus infection is decreased rather than increased by positive genetic selection.

    Science.gov (United States)

    Pedersen, Niels C; Liu, Hongwei; Durden, Monica; Lyons, Leslie A

    2016-03-01

    A previous study demonstrated the existence of a natural resistance to feline infectious peritonitis virus (FIPV) among 36% of randomly bred laboratory cats. A genome wide association study (GWAS) on this population suggested that resistance was polygenic but failed to identify any strong specific associations. In order to enhance the power of GWAS or whole genome sequencing to identify strong genetic associations, a decision was made to positively select for resistance over three generations. The inbreeding experiment began with a genetically related parental (P) population consisting of three toms and four queens identified from among the survivors of the earlier study and belonging to a closely related subgroup (B). The subsequent effects of inbreeding were measured using 42 genome-wide STR markers. P generation cats produced 57 first filial (F1) kittens, only five of which (9.0%) demonstrated a natural resistance to FIPV infection. One of these five F1 survivors was then used to produce six F1/P-backcrosses kittens, only one of which proved resistant to FIP. Six of eight of the F1 and F1/P survivors succumbed to a secondary exposure 4-12 months later. Therefore, survival after both primary and secondary infection was decreased rather than increased by positive selection for resistance. The common genetic factor associated with this diminished resistance was a loss of heterozygosity. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  6. Properties of realgar bioleaching using an extremely acidophilic bacterium and its antitumor mechanism as an anticancer agent.

    Science.gov (United States)

    Chen, Peng; Xu, Ruixiang; Yan, Lei; Wu, Zhengrong; Wei, Yan; Zhao, Wenbin; Wang, Xin; Xie, Qinjian; Li, Hongyu

    2017-05-22

    Realgar is a naturally occurring arsenic sulfide (or Xionghuang, in Chinese). It contains over 90% tetra-arsenic tetra-sulfide (As 4 S 4 ). Currently, realgar has been confirmed the antitumor activities, both in vitro and in vivo, of realgar extracted using Acidithiobacillus ferrooxidans (A. ferrooxidans). Bioleaching, a new technology to greatly improve the use rate of arsenic extraction from realgar using bacteria, is a novel methodology that addressed a limitation of the traditional method for realgar preparation. The present systematic review reports on the research progress in realgar bioleaching and its antitumor mechanism as an anticancer agent. A total of 93 research articles that report on the biological activity of extracts from realgar using bacteria and its preparation were presented in this review. The realgar bioleaching solution (RBS) works by inducing apoptosis when it is used to treat tumor cells in vitro and in vivo. When it is used to treat animal model organisms in vivo, such as mice and Caenorhabditis elegans, tumor tissues grew more slowly, with mass necrosis. Meanwhile, the agent also showed obvious inhibition of tumor cell growth. Bioleaching technology greatly improves the utilization of realgar and is a novel methodology to improve the traditional method.

  7. Antitumor activity of Bulgarian herb Tribulus terrestris L. on human breast cancer cells

    Directory of Open Access Journals (Sweden)

    Svetla Angelova

    2013-01-01

    Full Text Available Medicinal plants have been intensively studied as a source of antitumor compounds. Due to the beneficial climate conditions Bulgarian herbs have high pharmacological potential. Currently, the antitumor effect of the Bulgarian medicinal plant Tribulus terrestris L. on human cancer cell lines is not studied. The main active compounds of the plant are the steroid saponins.The present study aims to analyze the effect on cell viability and apoptotic activity of total extract and saponin fraction of Bulgarian Tribulus terrestris L. on human breast cancer (MCF7 and normal (MCF10A cell lines. Antitumor effect was established by МТТ cell viability assay and assessment of apoptotic potential was done through analysis of genomic integrity (DNA fragmentation assay and analysis of morphological cell changes (Fluorescence microscopy. The results showed that total extract of the herb has a marked dose-dependent inhibitory effect on viability of MCF7 cells (half maximal inhibitory concentration is 15 μg/ml. Cell viability of MCF10A was moderately decreased without visible dose-dependent effect. The saponin fraction has increased inhibitory effect on breast cancer cells compared to total extract. Morphological changes and DNA fragmentation were observed as markers for early and late apoptosis predominantly in tumor cells after treatment. Apoptotic processes were intensified with the increase of treatment duration.The obtained results are the first showing selective antitumor activity of Bulgarian Tribulus terrestris L. on human cancer cells in vitro. Apoptotic processes are involved in the antitumor mechanisms induced by the herb. This results give directions for future investigations concerning detailed assessment of its pharmacological potential.

  8. Anti-tumor activity of polysaccharides extracted from Senecio ...

    African Journals Online (AJOL)

    Purpose: To optimize the extraction conditions of polysaccharides from the root of Senecio scandens Buch,-Ham. (PRS) and evaluate its anti-tumor effect on hepatocellular carcinoma. Methods: Response surface methodology (RSM) applied with a Box-Behnken design (BBD, three levels and three factors) was employed to ...

  9. By inhibiting PFKFB3, aspirin overcomes sorafenib resistance in hepatocellular carcinoma.

    Science.gov (United States)

    Li, Sainan; Dai, Weiqi; Mo, Wenhui; Li, Jingjing; Feng, Jiao; Wu, Liwei; Liu, Tong; Yu, Qiang; Xu, Shizan; Wang, Wenwen; Lu, Xiya; Zhang, Qinghui; Chen, Kan; Xia, Yujing; Lu, Jie; Zhou, Yingqun; Fan, Xiaoming; Xu, Ling; Guo, Chuanyong

    2017-12-15

    Hepatocellular carcinoma (HCC) is one of the few cancers with a continuous increase in incidence and mortality. Drug resistance is a major problem in the treatment of HCC. In this study, two sorafenib-resistant HCC cell lines and a nude mouse subcutaneously tumor model were used to explore the possible mechanisms leading to sorafenib resistance, and to investigate whether aspirin could increase the sensitivity of hepatoma cells to sorafenib. The combination of aspirin and sorafenib resulted in a synergistic antitumor effect against liver tumors both in vitro and in vivo. High glycolysis and PFKFB3 overexpression occupied a dominant position in sorafenib resistance, and can be targeted and overcome by aspirin. Aspirin plus sorafenib induced apoptosis in tumors without inducing weight loss, hepatotoxicity or inflammation. Our results suggest that aspirin overcomes sorafenib resistance and their combination may be an effective treatment approach for HCC. © 2017 UICC.

  10. The effect of anti-tumor necrosis factor alpha agents on postoperative anastomotic complications in Crohn's disease

    DEFF Research Database (Denmark)

    El-Hussuna, Alaa Abdul-Hussein H; Krag, Aleksander; Olaison, Gunnar

    2013-01-01

    Patients with Crohn's disease treated with anti-tumor necrosis factor alpha agents may have an increased risk of surgical complications.......Patients with Crohn's disease treated with anti-tumor necrosis factor alpha agents may have an increased risk of surgical complications....

  11. Novel Antitumor Platinum(II) Conjugates Containing the Nonsteroidal Anti-inflammatory Agent Diclofenac: Synthesis and Dual Mechanisms of Antiproliferative Effects.

    Science.gov (United States)

    Intini, Francesco Paolo; Zajac, Juraj; Novohradsky, Vojtech; Saltarella, Teresa; Pacifico, Concetta; Brabec, Viktor; Natile, Giovanni; Kasparkova, Jana

    2017-02-06

    One concept how to improve anticancer effects of conventional metallodrugs consists in conjugation of these compounds with other biologically (antitumor) active agents, acting by a different mechanism. Here, we present synthesis, biological effects, and mechanisms of action of new Pt(II) derivatives containing one or two nonsteroidal anti-inflammatory diclofenac (DCF) ligands also known for their antitumor effects. The antiproliferative properties of these metallic conjugates show that these compounds are potent and cancer cell selective cytotoxic agents exhibiting activity in cisplatin resistant and the COX-2 positive tumor cell lines. One of these compounds, compound 3, in which DCF molecules are coordinated to Pt(II) through their carboxylic group, is more potent than parental conventional Pt(II) drug cisplatin, free DCF and the congeners of 3 in which DCF ligands are conjugated to Pt(II) via a diamine. The potency of 3 is due to several factors including enhanced internalization that correlates with enhanced DNA binding and cytotoxicity. Mechanistic studies show that 3 combines multiple effects. After its accumulation in cells, it releases Pt(II) drug capable of binding/damaging DNA and DCF ligands, which affect distribution of cells in individual phases of the cell cycle, inhibit glycolysis and lactate transport, collapse mitochondrial membrane potential, and suppress the cellular properties characteristic of metastatic progression.

  12. Food plant derived disease tolerance and resistance in a natural butterfly-plant-parasite interactions.

    Science.gov (United States)

    Sternberg, Eleanore D; Lefèvre, Thierry; Li, James; de Castillejo, Carlos Lopez Fernandez; Li, Hui; Hunter, Mark D; de Roode, Jacobus C

    2012-11-01

    Organisms can protect themselves against parasite-induced fitness costs through resistance or tolerance. Resistance includes mechanisms that prevent infection or limit parasite growth while tolerance alleviates the fitness costs from parasitism without limiting infection. Although tolerance and resistance affect host-parasite coevolution in fundamentally different ways, tolerance has often been ignored in animal-parasite systems. Where it has been studied, tolerance has been assumed to be a genetic mechanism, unaffected by the host environment. Here we studied the effects of host ecology on tolerance and resistance to infection by rearing monarch butterflies on 12 different species of milkweed food plants and infecting them with a naturally occurring protozoan parasite. Our results show that monarch butterflies experience different levels of tolerance to parasitism depending on the species of milkweed that they feed on, with some species providing over twofold greater tolerance than other milkweed species. Resistance was also affected by milkweed species, but there was no relationship between milkweed-conferred resistance and tolerance. Chemical analysis suggests that infected monarchs obtain highest fitness when reared on milkweeds with an intermediate concentration, diversity, and polarity of toxic secondary plant chemicals known as cardenolides. Our results demonstrate that environmental factors-such as interacting species in ecological food webs-are important drivers of disease tolerance. © 2012 The Author(s). Evolution© 2012 The Society for the Study of Evolution.

  13. Anti-tumor activity of polysaccharides extracted from Senecio ...

    African Journals Online (AJOL)

    *, Bao Zhang, Mingming Han, Xin Jin, Liyuan Sun and Tao Li. Department of ..... Yang J, Li X, Xue Y, Wang N, Liu W. Anti-hepatoma activity and mechanism of corn ... Peng W, Wu JG, Jiang YB, Liu YJ, Sun T, Wu N, Wu CJ. Antitumor activity of ...

  14. Reprogramming Antitumor Immune Responses with microRNAs

    Science.gov (United States)

    2013-10-01

    disease, including cancer etiology (4) and the generation and inhibition of antitumor immune responses (5–9). Biologically active miRNAs bind to MREs...breast, colorectal, lung, pancreatic , and thyroid carcinomas and in liquid tumors including lymphomas and some acute myeloid leukemias (9, 35). The...immunity [9], underscoring the potential of targeting this major microenvironmental compartment. Accumulating evidence suggests that chronic

  15. Antitumor Lipids--Structure, Functions, and Medical Applications.

    Science.gov (United States)

    Kostadinova, Aneliya; Topouzova-Hristova, Tanya; Momchilova, Albena; Tzoneva, Rumiana; Berger, Martin R

    2015-01-01

    Cell proliferation and metastasis are considered hallmarks of tumor progression. Therefore, efforts have been made to develop novel anticancer drugs that inhibit both the proliferation and the motility of tumor cells. Synthetic antitumor lipids (ATLs), which are chemically divided into two main classes, comprise (i) alkylphospholipids (APLs) and (ii) alkylphosphocholines (APCs). They represent a new entity of drugs with distinct antiproliferative properties in tumor cells. These compounds do not interfere with the DNA or mitotic spindle apparatus of the cell, instead, they incorporate into cell membranes, where they accumulate and interfere with lipid metabolism and lipid-dependent signaling pathways. Recently, it has been shown that the most commonly studied APLs inhibit proliferation by inducing apoptosis in malignant cells while leaving normal cells unaffected and are potent sensitizers of conventional chemo- and radiotherapy, as well as of electrical field therapy. APLs resist catabolic degradation to a large extent, therefore accumulate in the cell and interfere with lipid-dependent survival signaling pathways, notably PI3K-Akt and Raf-Erk1/2, and de novo phospholipid biosynthesis. They are internalized in the cell membrane via raft domains and cause downstream reactions as inhibition of cell growth and migration, cell cycle arrest, actin stress fibers collapse, and apoptosis. This review summarizes the in vitro, in vivo, and clinical trials of most common ATLs and their mode of action at molecular and biochemical levels. © 2015 Elsevier Inc. All rights reserved.

  16. Comparison of the fibronectin-binding ability and antitumor efficacy of various mycobacteria.

    Science.gov (United States)

    Hudson, M A; Ritchey, J K; Catalona, W J; Brown, E J; Ratliff, T L

    1990-07-01

    Although the mechanism by which Bacillus Calmette-Guerin (BCG) exerts an antitumor effect on superficial bladder tumors is not fully understood, recent evidence has implicated binding of BCG organisms to fibronectin (FN) as requisite for this antitumor efficacy. Various substrains of BCG and other mycobacteria were tested in vitro for their relative capacities to bind both matrix and soluble FN. A substrain of Mycobacterium kansasii, designated the "high-binding strain," was found to bind FN more readily (P less than 0.05) in in vitro studies, when compared to commercially available substrains of BCG (Tice, Connaught, and Armand Frappier). The binding by the three commercial strains of BCG to FN in vitro appeared to be equivalent. The high-binding strain was further demonstrated to attach more readily in vivo to the acutely injured murine bladder (P less than 0.005) than the Armand Frappier substrain. Finally, using the MB49 murine bladder tumor model, an enhanced antitumor effect (P less than 0.05) was noted in mice treated with intravesical high-binding strain, in comparison to the Armand Frappier substrain, during five weekly treatments. It appears not only that the commercial substrains of BCG bind FN in an equivalent manner but also that the relative binding capacities of the substrains correlate directly with antitumor activity. A substrain of M. kansasii appears to have been identified which may prove more clinically effective than the currently available strains of BCG.

  17. Curcuma increasing antitumor effect of Rhizoma paridis saponins through absorptive enhancement of paridis saponins.

    Science.gov (United States)

    Man, Shuli; Li, Yuanyuan; Fan, Wei; Gao, Wenyuan; Liu, Zhen; Li, Nan; Zhang, Yao; Liu, Changxiao

    2013-09-15

    Rhizoma paridis saponins (RPS) played a good antitumor role in many clinical applications. However, low oral bioavailability limited its application. In this research, water extract of Curcuma (CW) significantly increased antitumor effect of Rhizoma paridis saponins (RPS). GC-MS was used to identify its polar composition. HPLC was applied for determination of the content of curcuminoids in CW. As a result, 47 analytes with 0.65% of curcuminoids were identified in CW. According to the in vivo anti-tumor data, the best proportion of curcuminoids in CW with RPS was 16:500 (w/w). Using this ratio, curcuminoids significantly increased absorption of RPS in the everted rat duodenum sac system. In addition, curcuminoids decreased the promotion of RPS on rhodamine 123 efflux. The effect of curcuminoids was similar to that of the P-gp inhibitor, cyclosporin A in combination with RPS. In conclusion, drug combination of water extract of Curcuma with RPS was a good method to increase the antitumor effect of RPS. This combination would be a potent anticancer agent used in the prospective application. Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.

  18. Evaluation of Anti-tumor and Chemoresistance-lowering Effects of ...

    African Journals Online (AJOL)

    Evaluation of Anti-tumor and Chemoresistance-lowering Effects of Pectolinarigenin from Cirsium japonicum Fisch ex DC in Breast Cancer. Mingqian Lu, Xinhua Xu, Hongda Lu, Zhongxin Lu, Bingqing Xu, Chao Tan, Kezhi Shi, Rong Guo, Qingzhi Kong ...

  19. Total Synthesis of Natural Products Using Hypervalent Iodine Reagents

    Directory of Open Access Journals (Sweden)

    Gaetan eMaertens

    2015-01-01

    Full Text Available We present a review of natural product syntheses accomplished in our laboratory during the last five years. Each synthetic route features a phenol dearomatization promoted by an environmentally benign hypervalent iodine reagent. The dearomatizations demonstrate the aromatic ring umpolung concept, and involve stereoselective remodeling of the inert unsaturations of a phenol into a highly functionalized key intermediate that may contain a quaternary carbon center and a prochiral dienone system. Several new oxidative strategies were employed, including transpositions (1,3-alkyl shift and Prins-pinacol, a polycyclization, an ipso rearrangement, and direct nucleophilic additions at the phenol para position. Several alkaloids, heterocyclic compounds, and a polycyclic core have been achieved, including sceletenone (a serotonin reuptake inhibitor, acetylaspidoalbidine (an antitumor agent, fortucine (antiviral and antitumor, erysotramidine (curare-like effect, platensimycin (an antibiotic, and the main core of a kaurane diterpene (immunosuppressive agent and stimulator of apoptosis. These concise and in some cases enantioselective syntheses effectively demonstrate the importance of hypervalent iodine reagents in the total synthesis of bioactive natural products.

  20. Natural Variation in Resistance to Virus Infection in Dipteran Insects

    Directory of Open Access Journals (Sweden)

    William H. Palmer

    2018-03-01

    Full Text Available The power and ease of Drosophila genetics and the medical relevance of mosquito-transmitted viruses have made dipterans important model organisms in antiviral immunology. Studies of virus–host interactions at the molecular and population levels have illuminated determinants of resistance to virus infection. Here, we review the sources and nature of variation in antiviral immunity and virus susceptibility in model dipteran insects, specifically the fruit fly Drosophila melanogaster and vector mosquitoes of the genera Aedes and Culex. We first discuss antiviral immune mechanisms and describe the virus-specificity of these responses. In the following sections, we review genetic and microbiota-dependent variation in antiviral immunity. In the final sections, we explore less well-studied sources of variation, including abiotic factors, sexual dimorphism, infection history, and endogenous viral elements. We borrow from work on other pathogen types and non-dipteran species when it parallels or complements studies in dipterans. Understanding natural variation in virus–host interactions may lead to the identification of novel restriction factors and immune mechanisms and shed light on the molecular determinants of vector competence.

  1. Snake venoms components with antitumor activity in murine melanoma cells; Componentes derivados de venenos de serpentes com acao antitumoral em celulas de melanoma murino

    Energy Technology Data Exchange (ETDEWEB)

    Queiroz, Rodrigo Guimaraes

    2012-07-01

    Despite the constant advances in the treatment of cancer, this disease remains one of the main causes of mortality worldwide. So, the development of new treatment modalities is imperative. Snake venom causes a variety of biological effects because they constitute a complex mixture of substances as disintegrins, proteases (serine and metalo), phospholipases A2, L-amino acid oxidases and others. The goal of the present work is to evaluate a anti-tumor activity of some snake venoms fractions. There are several studies of components derived from snake venoms with this kind of activity. After fractionation of snake venoms of the families Viperidae and Elapidae, the fractions were assayed towards murine melanoma cell line B16-F10 and fibroblasts L929. The results showed that the fractions of venom of the snake Notechis ater niger had higher specificity and potential antitumor activity on B16-F10 cell line than the other studied venoms. Since the components of this venom are not explored yet coupled with the potential activity showed in this work, we decided to choose this venom to develop further studies. The cytotoxic fractions were evaluated to identify and characterize the components that showed antitumoral activity. Western blot assays and zymography suggests that these proteins do not belong to the class of metallo and serine proteinases. (author)

  2. Baseline clinical predictors of antitumor response to the PARP inhibitor olaparib in germline BRCA1/2 mutated patients with advanced ovarian cancer.

    Science.gov (United States)

    Rafii, Saeed; Gourley, Charlie; Kumar, Rajiv; Geuna, Elena; Ern Ang, Joo; Rye, Tzyvia; Chen, Lee-May; Shapira-Frommer, Ronnie; Friedlander, Michael; Matulonis, Ursula; De Greve, Jacques; Oza, Amit M; Banerjee, Susana; Molife, L Rhoda; Gore, Martin E; Kaye, Stan B; Yap, Timothy A

    2017-07-18

    The PARP inhibitor olaparib was recently granted Food and Drug Administration (FDA) accelerated approval in patients with advanced BRCA1/2 mutation ovarian cancer. However, antitumor responses are observed in only approximately 40% of patients and the impact of baseline clinical factors on response to treatment remains unclear. Although platinum sensitivity has been suggested as a marker of response to PARP inhibitors, patients with platinum-resistant disease still respond to olaparib. 108 patients with advanced BRCA1/2 mutation ovarian cancers were included. The interval between the end of the most recent platinum chemotherapy and PARPi (PTPI) was used to predict response to olaparib independent of conventional definition of platinum sensitivity. RECIST complete response (CR) and partial response (PR) rates were 35% in patients with platinum-sensitive versus 13% in platinum-resistant (p<0.005). Independent of platinum sensitivity status, the RECIST CR/PR rates were 42% in patients with PTPI greater than 52 weeks and 18% in patients with PTPI less than 52 weeks (p=0.016). No association was found between baseline clinical factors such as FIGO staging, debulking surgery, BRCA1 versus BRCA2 mutations, prior history of breast cancer and prior chemotherapy for breast cancer, and the response to olaparib. We conducted an international multicenter retrospective study to investigate the association between baseline clinical characteristics of patients with advanced BRCA1/2 mutation ovarian cancers from eight different cancer centers and their antitumor response to olaparib. PTPI may be used to refine the prediction of response to PARP inhibition based on the conventional categorization of platinum sensitivity.

  3. Hederagenin Induces Apoptosis in Cisplatin-Resistant Head and Neck Cancer Cells by Inhibiting the Nrf2-ARE Antioxidant Pathway

    Directory of Open Access Journals (Sweden)

    Eun Hye Kim

    2017-01-01

    Full Text Available Acquired resistance to cisplatin is the most common reason for the failure of cisplatin chemotherapy. Hederagenin, triterpenoids extracted from ivy leaves, exhibits antitumor activity in various types of cancer. However, the therapeutic potential of hederagenin in head and neck cancer (HNC has remained unclear. Therefore, we examined the effects of hederagenin in cisplatin-resistant HNC cells and characterized its molecular mechanisms of action in this context. We evaluated the effects of hederagenin treatment on cell viability, apoptosis, reactive oxygen species (ROS production, glutathione levels, mitochondrial membrane potential (ΔΨm, and protein and mRNA expression in HNC cells. The antitumor effect of hederagenin in mouse tumor xenograft models was also analyzed. Hederagenin selectively induced cell death in both cisplatin-sensitive and cisplatin-resistant HNC cells by promoting changes in ΔΨm and inducing apoptosis. Hederagenin inhibited the Nrf2-antioxidant response element (ARE pathway and activated p53 in HNC cells, thereby enhancing ROS production and promoting glutathione depletion. These effects were reversed by the antioxidant trolox. Hederagenin activated intrinsic apoptotic pathways via cleaved PARP, cleaved caspase-3, and Bax. The selective inhibitory effects of hederagenin were confirmed in cisplatin-resistant HNC xenograft models. These data suggest that hederagenin induces cell death in resistant HNC cells via the Nrf2-ARE antioxidant pathway.

  4. Assessment of in vitro antitumoral and antimicrobial activities of ...

    African Journals Online (AJOL)

    Assessment of in vitro antitumoral and antimicrobial activities of marine algae harvested from the eastern Mediterranean sea. ... African Journal of Biotechnology ... algal extracts obtained from the marine algae Scytosiphon lomentaria, Padina pavonica, Cystoseira mediterranea (Phaeophyceae), Hypnea musciformis and ...

  5. Gut microbiome can control antitumor immune function in liver

    Science.gov (United States)

    An NCI study in mice that found a connection between gut bacteria and antitumor immune responses in the liver has implications for understanding mechanisms that lead to liver cancer and for potential treatments. The study was published in Science.

  6. Antitumor Active Protein-containing Glycans from the Body of Ganoderma tsugae

    Institute of Scientific and Technical Information of China (English)

    LIU Ying; LI Yue-fei; ZHENG Ke-yan; FEI Xiao-fang

    2012-01-01

    To explore the effects of traditional herbal medicine Ganoderma tsugae(G.tsugae) on immunomodulatory and antitumor activities,the crude polysaccharides ofG.tsugae were purified by filtration,diethylaminoethyl(DEAE)sepharose-fast flow chromatography and sephadex G-100 size-exclusion chromatography.Two main fractions,protein-containing glycans CSSLP-I and CSSLP-2,were obtained via the gradient elution.The protein content,molecular weight,and monosaccharide composition of the two fractions were analyzed.Furthermore,the influence of the protein-containing glycans from G.tsugae on the activation of human acute monocytic leukemia cell line(THP-1 ) and their antitumor activities to the human hepatocellular liver carcinoma cell(HepG-2) in vitro were evaluated.The results indicate that CSSLP-I and CSSLP-2 could increase the pinocytic activity of THP-1 cells and induce THP-1 cells to produce the cytokines of TNFa and IL-2,significantly.CSSLP-1 and CSSLP-2 also played an inhibiting effect on the cancer cell(NepG-2).Moreover,the anti-proliferation activity of CSSLP-1 and CSSLP-2 increased with the participation of TNFa and 1L-2 or other antitumor factors induced from THP-1 cclls by G.tsugae protein-containing glycan fractions.

  7. Impact of antitumor therapy on nutrition

    International Nuclear Information System (INIS)

    Kokal, W.A.

    1985-01-01

    The treatment of the cancer patient by surgery, chemotherapy or radiation therapy can impose significant nutritional disabilities on the host. The nutritional disabilities seen in the tumor-bearing host from antitumor therapy are produced by factors which either limit oral intake or cause malabsorption of nutrients. The host malnutrition caused as a consequence of surgery, chemotherapy or radiation therapy assumes even more importance when one realizes that many cancer patients are already debilitated from their disease

  8. Juglans regia Hexane Extract Exerts Antitumor Effect, Apoptosis ...

    African Journals Online (AJOL)

    Original Research Article. Juglans regia Hexane Extract Exerts Antitumor Effect,. Apoptosis Induction and Cell Circle Arrest in Prostate. Cancer Cells In vitro. Wei Li1, De-Yuan Li2*, ... composition of walnut is juglone (5-hydroxy-1, 4- naphthoquinone), the .... extract was confirmed by studying apoptotic body formation using ...

  9. Anti-tumor effect of polysaccharides isolated from Taraxacum ...

    African Journals Online (AJOL)

    The effects of extraction temperature, liquid-solid ratio and extraction time on the yield of PTM were investigated using a Box-Behnken design (BBD). The in vitro anti-tumor effect of PTM on MCF-7 cells was investigated by methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay, while the mechanism of PTM-induced ...

  10. Induction of anti-tumor immunity by trifunctional antibodies in patients with peritoneal carcinomatosis

    Directory of Open Access Journals (Sweden)

    Lindhofer Horst

    2009-02-01

    Full Text Available Abstract Peritoneal carcinomatosis (PC from epithelial tumors is a fatal diagnosis without efficient treatment. Trifunctional antibodies (trAb are novel therapeutic approaches leading to a concerted anti-tumor activity resulting in tumor cell destruction. In addition, preclinical data in mouse tumor models demonstrated the induction of long lasting tumor immunity after treatment with trAb. We describe the induction of anti-tumor specific T-lymphocytes after intraperitoneal administration of trAb in patients with PC. 9 patients with progressive PC from gastric (n = 6 and ovarian cancer (n = 2, and cancer of unknown primary (n = 1 received 3 escalating doses of trAb after surgery and/or ineffective chemotherapy. The trAb EpCAM × CD3 (10, 20, 40 μg or HER2/neu × CD3 (10, 40, 80 μg were applicated by intraperitoneal infusion. Four weeks after the last trAb application, all patients were restimulated by subdermal injection of trAb + autologous PBMC + irradiated autologous tumor cells. Immunological reactivity was tested by analyzing PBMC for specific tumor reactive CD4+/CD8+ T lymphocytes using an IFN-γ secretion assay. In 5 of 9 patients, tumor reactive CD4+/CD8+ T-lymphocytes increased significantly, indicating specific anti-tumor immunity. A clinical response (stable disease, partial regression has been observed in 5 of 9 patients, with a mean time to progression of 3.6 months. Follow-up showed a mean survival of 11.8 months (median 8.0 months after trAb therapy. TrAb are able to induce anti-tumor immunity after intraperitoneal application and restimulation. The induction of long-lasting anti-tumor immunity may provide an additional benefit of the intraperitoneal therapy with trAb and should be further elevated in larger clinical trials.

  11. Effect of Au-dextran NPs as anti-tumor agent against EAC and solid tumor in mice by biochemical evaluations and histopathological investigations.

    Science.gov (United States)

    Medhat, Dalia; Hussein, Jihan; El-Naggar, Mehrez E; Attia, Mohamed F; Anwar, Mona; Latif, Yasmine Abdel; Booles, Hoda F; Morsy, Safaa; Farrag, Abdel Razik; Khalil, Wagdy K B; El-Khayat, Zakaria

    2017-07-01

    Dextran-capped gold nanoparticles (Au-dextran NPs) were prepared exploiting the natural polysaccharide polymer as both reducing and stabilizing agent in the synthesis process, aiming at studying their antitumor effect on solid carcinoma and EAC-bearing mice. To this end, Au-dextran NPs were designed via simple eco-friendly chemical reaction and they were characterized revealing the monodispersed particles with narrow distributed size of around 49nm with high negative charge. In vivo experiments were performed on mice. Biochemical analysis of liver and kidney functions and oxidation stress ratio in addition to histopathological investigations of such tumor tissues were done demonstrating the potentiality of Au-dextran NPs as antitumor agent. The obtained results revealed that EAC and solid tumors caused significant increase in liver and kidney functions, liver oxidant parameters, alpha feto protein levels and diminished liver antioxidant accompanied by positive expression of tumor protein p53 of liver while the treatment with Au-dextran NPs for both types caused improvement in liver and kidney functions, increased liver antioxidant, increased the expression level of B-cell lymphoma 2 gene and subsequently suppressed the apoptotic pathway. As a result, the obtained data provides significant antitumor effects of the Au-dextran NPs in both Ehrlich ascites and solid tumor in mice models. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  12. Naturally occurring broad-spectrum powdery mildw resistance in a central American tomato accession is caused by loss of Mlo function

    NARCIS (Netherlands)

    Bai, Y.; Pavan, S.N.C.; Zheng, Z.; Zappel, N.F.; Reinstadler, A.; Lotti, C.; Giovanni, de C.; Ricciardi, L.; Lindhout, P.; Visser, R.G.F.; Theres, K.; Panstruga, R.

    2008-01-01

    The resistant cherry tomato (Solanum lycopersicum var. cerasiforme) line LC-95, derived from an accession collected in Ecuador, harbors a natural allele (ol-2) that confers broad-spectrum and recessively inherited resistance to powdery mildew (Oidium neolycopersici). As both the genetic and

  13. Cytotoxicity and anti-tumor effects of new ruthenium complexes on triple negative breast cancer cells.

    Directory of Open Access Journals (Sweden)

    Cecília P Popolin

    Full Text Available Triple-negative breast cancer (TNBC is a highly aggressive breast cancer subtype. The high rate of metastasis associated to the fact that these cells frequently display multidrug resistance, make the treatment of metastatic disease difficult. Development of antitumor metal-based drugs was started with the discovery of cisplatin, however, the severe side effects represent a limitation for its clinical use. Ruthenium (Ru complexes with different ligands have been successfully studied as prospective antitumor drugs. In this work, we demonstrated the activity of a series of biphosphine bipyridine Ru complexes (1 [Ru(SO4(dppb(bipy], (2 [Ru(CO3(dppb(bipy], (3 [Ru(C2O4(dppb(bipy] and (4 [Ru(CH3CO2(dppb(bipy]PF6 [where dppb = 1,4-bis(diphenylphosphinobutane and bipy = 2,2'-bipyridine], on proliferation of TNBC (MDA-MB-231, estrogen-dependent breast tumor cells (MCF-7 and a non-tumor breast cell line (MCF-10A. Complex (4 was most effective among the complexes and was selected to be further investigated on effects on tumor cell adhesion, migration, invasion and in apoptosis. Moreover, DNA and HSA binding properties of this complex were also investigated. Results show that complex (4 was more efficient inhibiting proliferation of MDA-MB-231 cells over non-tumor cells. In addition, complex (4 was able to inhibit MDA-MB231 cells adhesion, migration and invasion and to induce apoptosis and inhibit MMP-9 secretion in TNBC cells. Complex (4 should be further investigated in vivo in order to stablish its potential to improve breast cancer treatment.

  14. Human CD1d-Restricted Natural Killer T (NKT) Cell Cytotoxicity Against Myeloid Cells

    National Research Council Canada - National Science Library

    Chen, Xiuxu; Gumperz, Jenny E

    2006-01-01

    CD1d-restricted natural killer T cells (NKT cells) are a unique subpopulation of T lymphocytes that have been shown to be able to promote potent anti-tumor responses in a number of different murine (mouse...

  15. Depletion of tumor-associated macrophages switches the epigenetic profile of pancreatic cancer infiltrating T cells and restores their anti-tumor phenotype.

    Science.gov (United States)

    Borgoni, Simone; Iannello, Andrea; Cutrupi, Santina; Allavena, Paola; D'Incalci, Maurizio; Novelli, Francesco; Cappello, Paola

    2018-01-01

    Pancreatic Ductal Adenocarcinoma (PDA) is characterized by a complex tumor microenvironment that supports its progression, aggressiveness and resistance to therapies. The delicate interplay between cancer and immune cells creates the conditions for PDA development, particularly due to the functional suppression of T cell anti-tumor effector activity. However, some of the mechanisms involved in this process are still poorly understood. In this study, we analyze whether the functional and epigenetic profile of T cells that infiltrate PDA is modulated by the microenvironment, and in particular by tumor-associated macrophages (TAMs). CD4 and CD8 T cells obtained from mice orthotopically injected with syngeneic PDA cells, and untreated or treated with Trabectedin, a cytotoxic drug that specifically targets TAMs, were sorted and analyzed by flow cytometry and characterized for their epigenetic profile. Assessment of cytokine production and the epigenetic profile of genes coding for IL10, T-bet and PD1 revealed that T cells that infiltrated PDA displayed activated Il10 promoter and repressed T-bet activity, in agreement with their regulatory phenotype (IL10 high /IFNγ low , PD1 high ). By contrast, in Trabectedin-treated mice, PDA-infiltrating T cells displayed repressed Il10 and Pdcd1 and activated T-bet promoter activity, in accordance with their anti-tumor effector phenotype (IL10 low /IFNγ high ), indicating a key role of TAMs in orchestrating functions of PDA-infiltrating T cells by modulating their epigenetic profile towards a pro-tumoral phenotype. These results suggest the targeting of TAMs as an efficient strategy to obtain an appropriate T cell anti-tumor immune response and open new potential combinations for PDA treatment.

  16. Novel Imidazopyridine Derivatives Possess Anti-Tumor Effect on Human Castration-Resistant Prostate Cancer Cells.

    Directory of Open Access Journals (Sweden)

    Matthew A Ingersoll

    Full Text Available Prostate cancer (PCa is the second leading cause of cancer-related death afflicting United States males. Most treatments to-date for metastatic PCa include androgen-deprivation therapy and second-generation anti-androgens such as abiraterone acetate and enzalutamide. However, a majority of patients eventually develop resistance to these therapies and relapse into the lethal, castration-resistant form of PCa to which no adequate treatment option remains. Hence, there is an immediate need to develop effective therapeutic agents toward this patient population. Imidazopyridines have recently been shown to possess Akt kinase inhibitory activity; thus in this study, we investigated the inhibitory effect of novel imidazopyridine derivatives HIMP, M-MeI, OMP, and EtOP on different human castration-resistant PCa cells. Among these compounds, HIMP and M-MeI were found to possess selective dose- and time-dependent growth inhibition: they reduced castration-resistant PCa cell proliferation and spared benign prostate epithelial cells. Using LNCaP C-81 cells as the model system, these compounds also reduced colony formation as well as cell adhesion and migration, and M-MeI was the most potent in all studies. Further investigation revealed that while HIMP primarily inhibits PCa cell growth via suppression of PI3K/Akt signaling pathway, M-MeI can inhibit both PI3K/Akt and androgen receptor pathways and arrest cell growth in the G2 phase. Thus, our results indicate the novel compound M-MeI to be a promising candidate for castration-resistant PCa therapy, and future studies investigating the mechanism of imidazopyridine inhibition may aid to the development of effective anti-PCa agents.

  17. Novel Imidazopyridine Derivatives Possess Anti-Tumor Effect on Human Castration-Resistant Prostate Cancer Cells.

    Science.gov (United States)

    Ingersoll, Matthew A; Lyons, Anastesia S; Muniyan, Sakthivel; D'Cunha, Napoleon; Robinson, Tashika; Hoelting, Kyle; Dwyer, Jennifer G; Bu, Xiu R; Batra, Surinder K; Lin, Ming-Fong

    2015-01-01

    Prostate cancer (PCa) is the second leading cause of cancer-related death afflicting United States males. Most treatments to-date for metastatic PCa include androgen-deprivation therapy and second-generation anti-androgens such as abiraterone acetate and enzalutamide. However, a majority of patients eventually develop resistance to these therapies and relapse into the lethal, castration-resistant form of PCa to which no adequate treatment option remains. Hence, there is an immediate need to develop effective therapeutic agents toward this patient population. Imidazopyridines have recently been shown to possess Akt kinase inhibitory activity; thus in this study, we investigated the inhibitory effect of novel imidazopyridine derivatives HIMP, M-MeI, OMP, and EtOP on different human castration-resistant PCa cells. Among these compounds, HIMP and M-MeI were found to possess selective dose- and time-dependent growth inhibition: they reduced castration-resistant PCa cell proliferation and spared benign prostate epithelial cells. Using LNCaP C-81 cells as the model system, these compounds also reduced colony formation as well as cell adhesion and migration, and M-MeI was the most potent in all studies. Further investigation revealed that while HIMP primarily inhibits PCa cell growth via suppression of PI3K/Akt signaling pathway, M-MeI can inhibit both PI3K/Akt and androgen receptor pathways and arrest cell growth in the G2 phase. Thus, our results indicate the novel compound M-MeI to be a promising candidate for castration-resistant PCa therapy, and future studies investigating the mechanism of imidazopyridine inhibition may aid to the development of effective anti-PCa agents.

  18. Unique antitumor property of the Mg-Ca-Sr alloys with addition of Zn

    Science.gov (United States)

    Wu, Yuanhao; He, Guanping; Zhang, Yu; Liu, Yang; Li, Mei; Wang, Xiaolan; Li, Nan; Li, Kang; Zheng, Guan; Zheng, Yufeng; Yin, Qingshui

    2016-02-01

    In clinical practice, tumor recurrence and metastasis after orthopedic prosthesis implantation is an intensely troublesome matter. Therefore, to develop implant materials with antitumor property is extremely necessary and meaningful. Magnesium (Mg) alloys possess superb biocompatibility, mechanical property and biodegradability in orthopedic applications. However, whether they possess antitumor property had seldom been reported. In recent years, it showed that zinc (Zn) not only promote the osteogenic activity but also exhibit good antitumor property. In our present study, Zn was selected as an alloying element for the Mg-1Ca-0.5Sr alloy to develop a multifunctional material with antitumor property. We investigated the influence of the Mg-1Ca-0.5Sr-xZn (x = 0, 2, 4, 6 wt%) alloys extracts on the proliferation rate, cell apoptosis, migration and invasion of the U2OS cell line. Our results show that Zn containing Mg alloys extracts inhibit the cell proliferation by alteration the cell cycle and inducing cell apoptosis via the activation of the mitochondria pathway. The cell migration and invasion property were also suppressed by the activation of MAPK (mitogen-activated protein kinase) pathway. Our work suggests that the Mg-1Ca-0.5Sr-6Zn alloy is expected to be a promising orthopedic implant in osteosarcoma limb-salvage surgery for avoiding tumor recurrence and metastasis.

  19. Colloidally stable surface-modified iron oxide nanoparticles: Preparation, characterization and anti-tumor activity

    Energy Technology Data Exchange (ETDEWEB)

    Macková, Hana [Institute of Macromolecular Chemistry, AS CR, Heyrovsky Sq. 2, 162 06 Prague 6 (Czech Republic); Horák, Daniel, E-mail: horak@imc.cas.cz [Institute of Macromolecular Chemistry, AS CR, Heyrovsky Sq. 2, 162 06 Prague 6 (Czech Republic); Donchenko, Georgiy Viktorovich; Andriyaka, Vadim Ivanovich; Palyvoda, Olga Mikhailovna; Chernishov, Vladimir Ivanovich [Palladin Institute of Biochemistry, NASU, 9 Leontovich St., 01601 Kiev (Ukraine); Chekhun, Vasyl Fedorovich; Todor, Igor Nikolaevich [R. E. Kavetsky Institute of Experimental Pathology, Oncology and Radiobiology, NASU, 45 Vasylkivska St., 03022 Kiev (Ukraine); Kuzmenko, Oleksandr Ivanovich [Palladin Institute of Biochemistry, NASU, 9 Leontovich St., 01601 Kiev (Ukraine)

    2015-04-15

    Maghemite (γ-Fe{sub 2}O{sub 3}) nanoparticles were obtained by co-precipitation of Fe(II) and Fe(III) chlorides and subsequent oxidation with sodium hypochlorite and coated with poly(N,N-dimethylacrylamide-co-acrylic acid) [P(DMAAm-AA)]. They were characterized by a range of methods including transmission electron microscopy (TEM), elemental analysis, dynamic light scattering (DLS) and zeta potential measurements. The effect of superparamagnetic P(DMAAm-AA)-γ-Fe{sub 2}O{sub 3} nanoparticles on oxidation of blood lipids, glutathione and proteins in blood serum was detected using 2-thiobarbituric acid and the ThioGlo fluorophore. Finally, mice received magnetic nanoparticles administered per os and the antitumor activity of the particles was tested on Lewis lung carcinoma (LLC) in male mice line C57BL/6 as an experimental in vivo metastatic tumor model; the tumor size was measured and the number of metastases in lungs was determined. Surface-modified γ-Fe{sub 2}O{sub 3} nanoparticles showed higher antitumor and antimetastatic activities than commercial CuFe{sub 2}O{sub 4} particles and the conventional antitumor agent cisplatin. - Highlights: • Maghemite nanoparticles were prepared and characterized. • Poly(N,N-dimethylacrylamide-co-acrylic acid) coating was synthetized. • Blood lipid, glutathione and protein peroxidation/oxidation was determined. • Antitumor effect of coated particles on Lewis lung carcinoma in mice was observed.

  20. Proton pump inhibitors while belonging to the same family of generic drugs show different anti-tumor effect.

    Science.gov (United States)

    Lugini, Luana; Federici, Cristina; Borghi, Martina; Azzarito, Tommaso; Marino, Maria Lucia; Cesolini, Albino; Spugnini, Enrico Pierluigi; Fais, Stefano

    2016-08-01

    Tumor acidity represents a major cause of chemoresistance. Proton pump inhibitors (PPIs) can neutralize tumor acidity, sensitizing cancer cells to chemotherapy. To compare the anti-tumor efficacy of different PPIs in vitro and in vivo. In vitro experiments PPIs anti-tumor efficacy in terms of cell proliferation and cell death/apoptosis/necrosis evaluation were performed. In vivo PPIs efficacy experiments were carried out using melanoma xenograft model in SCID mice. Lansoprazole showed higher anti-tumor effect when compared to the other PPIs. The lansoprazole effect lasted even upon drug removal from the cell culture medium and it was independent from the lipophilicity of the PPIs formulation. These PPIs have shown different anti-tumoral efficacy, and the most effective at low dose was lansoprazole. The possibility to contrast tumor acidity by off-label using PPIs opens a new field of oncology investigation.

  1. Beneficial Phytochemicals with Anti-Tumor Potential Revealed through Metabolic Profiling of New Red Pigmented Lettuces (Lactuca sativa L.

    Directory of Open Access Journals (Sweden)

    Xiao-Xiao Qin

    2018-04-01

    Full Text Available The present study aimed to compare polyphenols among red lettuce cultivars and identify suitable cultivars for the development and utilization of healthy vegetables. Polyphenols, mineral elements, and antioxidant activity were analyzed in the leaves of six red pigmented lettuce (Lactuca sativa L. cultivars; thereafter, we assessed the anti-tumor effects of cultivar B-2, which displayed the highest antioxidant activity. Quadrupole–Orbitrap mass spectrometry analysis revealed four classes of polyphenols in these cultivars. The composition and contents of these metabolites varied significantly among cultivars and primarily depended on leaf color. The B-2 cultivar had the highest antioxidant potential than others because it contained the highest levels of polyphenols, especially anthocyanin, flavone, and phenolic acid; furthermore, this cultivar displayed anti-tumor effects against the human lung adenocarcinoma cell line A549, human hepatoma cell line Bel7402, human cancer colorectal adenoma cell line HCT-8, and HT-29 human colon cancer cell line. Hence, the new red-leaf lettuce cultivar B-2 has a distinct metabolite profile, with high potential for development and utilization of natural phytochemical and mineral resources in lettuces and can be used as a nutrient-dense food product.

  2. Beneficial Phytochemicals with Anti-Tumor Potential Revealed through Metabolic Profiling of New Red Pigmented Lettuces (Lactuca sativa L.).

    Science.gov (United States)

    Qin, Xiao-Xiao; Zhang, Ming-Yue; Han, Ying-Yan; Hao, Jing-Hong; Liu, Chao-Jie; Fan, Shuang-Xi

    2018-04-11

    The present study aimed to compare polyphenols among red lettuce cultivars and identify suitable cultivars for the development and utilization of healthy vegetables. Polyphenols, mineral elements, and antioxidant activity were analyzed in the leaves of six red pigmented lettuce ( Lactuca sativa L.) cultivars; thereafter, we assessed the anti-tumor effects of cultivar B-2, which displayed the highest antioxidant activity. Quadrupole-Orbitrap mass spectrometry analysis revealed four classes of polyphenols in these cultivars. The composition and contents of these metabolites varied significantly among cultivars and primarily depended on leaf color. The B-2 cultivar had the highest antioxidant potential than others because it contained the highest levels of polyphenols, especially anthocyanin, flavone, and phenolic acid; furthermore, this cultivar displayed anti-tumor effects against the human lung adenocarcinoma cell line A549, human hepatoma cell line Bel7402, human cancer colorectal adenoma cell line HCT-8, and HT-29 human colon cancer cell line. Hence, the new red-leaf lettuce cultivar B-2 has a distinct metabolite profile, with high potential for development and utilization of natural phytochemical and mineral resources in lettuces and can be used as a nutrient-dense food product.

  3. Valproic acid sensitizes metformin-resistant human renal cell carcinoma cells by upregulating H3 acetylation and EMT reversal.

    Science.gov (United States)

    Wei, Muyun; Mao, Shaowei; Lu, Guoliang; Li, Liang; Lan, Xiaopeng; Huang, Zhongxian; Chen, Yougen; Zhao, Miaoqing; Zhao, Yueran; Xia, Qinghua

    2018-04-17

    Metformin (Met) is a widely available diabetic drug and shows suppressed effects on renal cell carcinoma (RCC) metabolism and proliferation. Laboratory studies in RCC suggested that metformin has remarkable antitumor activities and seems to be a potential antitumor drug. But the facts that metformin may be not effective in reducing the risk of RCC in cancer clinical trials made it difficult to determine the benefits of metformin in RCC prevention and treatment. The mechanisms underlying the different conclusions between laboratory experiments and clinical analysis remains unclear. The goal of the present study was to determine whether long-term metformin use can induce resistance in RCC, whether metformin resistance could be used to explain the disaccord in laboratory and clinical studies, and whether the drug valproic acid (VPA), which inhibits histone deacetylase, exhibits synergistic cytotoxicity with metformin and can counteract the resistance of metformin in RCC. We performed CCK8, transwell, wound healing assay, flow cytometry and western blotting to detect the regulations of proliferation, migration, cell cycle and apoptosis in 786-O, ACHN and metformin resistance 786-O (786-M-R) cells treated with VPA, metformin or a combination of two drugs. We used TGF-β, SC79, LY294002, Rapamycin, protein kinase B (AKT) inhibitor to treat the 786-O or 786-M-R cells and detected the regulations in TGF-β /pSMAD3 and AMPK/AKT pathways. 786-M-R was refractory to metformin-induced antitumor effects on proliferation, migration, cell cycle and cell apoptosis. AMPK/AKT pathways and TGF-β/SMAD3 pathways showed low sensibilities in 786-M-R. The histone H3 acetylation diminished in the 786-M-R cells. However, the addition of VPA dramatically upregulated histone H3 acetylation, increased the sensibility of AKT and inhibited pSMAD3/SMAD4, letting the combination of VPA and metformin remarkably reappear the anti-tumour effects of metformin in 786-M-R cells. VPA not only exhibits

  4. Tertiary Lymphoid Structures in Cancer: Drivers of Antitumor Immunity, Immunosuppression, or Bystander Sentinels in Disease?

    Science.gov (United States)

    Colbeck, Emily Jayne; Ager, Ann; Gallimore, Awen; Jones, Gareth Wyn

    2017-01-01

    Secondary lymphoid organs are integral to initiation and execution of adaptive immune responses. These organs provide a setting for interactions between antigen-specific lymphocytes and antigen-presenting cells recruited from local infected or inflamed tissues. Secondary lymphoid organs develop as a part of a genetically preprogrammed process during embryogenesis. However, organogenesis of secondary lymphoid tissues can also be recapitulated in adulthood during de novo lymphoid neogenesis of tertiary lymphoid structures (TLSs). These ectopic lymphoid-like structures form in the inflamed tissues afflicted by various pathological conditions, including cancer, autoimmunity, infection, or allograft rejection. Studies are beginning to shed light on the function of such structures in different disease settings, raising important questions regarding their contribution to progression or resolution of disease. Data show an association between the tumor-associated TLSs and a favorable prognosis in various types of human cancer, attracting the speculation that TLSs support effective local antitumor immune responses. However, definitive evidence for the role for TLSs in fostering immune responses in vivo are lacking, with current data remaining largely correlative by nature. In fact, some more recent studies have even demonstrated an immunosuppressive, tumor-promoting role for cancer-associated TLSs. In this review, we will discuss what is known about the development of cancer-associated TLSs and the current understanding of their potential role in the antitumor immune response. PMID:29312327

  5. Snake venoms components with antitumor activity in murine melanoma cells

    International Nuclear Information System (INIS)

    Queiroz, Rodrigo Guimaraes

    2012-01-01

    Despite the constant advances in the treatment of cancer, this disease remains one of the main causes of mortality worldwide. So, the development of new treatment modalities is imperative. Snake venom causes a variety of biological effects because they constitute a complex mixture of substances as disintegrins, proteases (serine and metalo), phospholipases A2, L-amino acid oxidases and others. The goal of the present work is to evaluate a anti-tumor activity of some snake venoms fractions. There are several studies of components derived from snake venoms with this kind of activity. After fractionation of snake venoms of the families Viperidae and Elapidae, the fractions were assayed towards murine melanoma cell line B16-F10 and fibroblasts L929. The results showed that the fractions of venom of the snake Notechis ater niger had higher specificity and potential antitumor activity on B16-F10 cell line than the other studied venoms. Since the components of this venom are not explored yet coupled with the potential activity showed in this work, we decided to choose this venom to develop further studies. The cytotoxic fractions were evaluated to identify and characterize the components that showed antitumoral activity. Western blot assays and zymography suggests that these proteins do not belong to the class of metallo and serine proteinases. (author)

  6. [Naturally occurring oseltamivir resistance in influenza A.

    DEFF Research Database (Denmark)

    Madsen, Laura; Nielsen, Alex; Lundgren, Jens

    2010-01-01

    in the development of resistance. The best prevention strategy remains vaccination of the general population to avoid immunity. Future antiviral treatment calls for knowledge about resistance to existing types of influenza and the availability of all three types of antiviral medication. Udgivelsesdato: 2010-Aug......During the last two influenza seasons, one of the predominant influenza A types (H1N1) has developed complete resistance to oseltamivir, the primary treatment option. The virus does, however, remain sensitive to zanamavir and amantadine. There is no unequivocal explanation for this slide...

  7. [Naturally occurring oseltamivir resistance in influenza A.

    DEFF Research Database (Denmark)

    Madsen, Laura; Nielsen, Alex; Lundgren, Jens

    2010-01-01

    During the last two influenza seasons, one of the predominant influenza A types (H1N1) has developed complete resistance to oseltamivir, the primary treatment option. The virus does, however, remain sensitive to zanamavir and amantadine. There is no unequivocal explanation for this slide...... in the development of resistance. The best prevention strategy remains vaccination of the general population to avoid immunity. Future antiviral treatment calls for knowledge about resistance to existing types of influenza and the availability of all three types of antiviral medication. Udgivelsesdato: 2010-Aug...

  8. Antitumor effect of novel anti-podoplanin antibody NZ-12 against malignant pleural mesothelioma in an orthotopic xenograft model.

    Science.gov (United States)

    Abe, Shinji; Kaneko, Mika Kato; Tsuchihashi, Yuki; Izumi, Toshihiro; Ogasawara, Satoshi; Okada, Naoto; Sato, Chiemi; Tobiume, Makoto; Otsuka, Kenji; Miyamoto, Licht; Tsuchiya, Koichiro; Kawazoe, Kazuyoshi; Kato, Yukinari; Nishioka, Yasuhiko

    2016-09-01

    Podoplanin (aggrus) is highly expressed in several types of cancers, including malignant pleural mesothelioma (MPM). Previously, we developed a rat anti-human podoplanin mAb, NZ-1, and a rat-human chimeric anti-human podoplanin antibody, NZ-8, derived from NZ-1, which induced antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity against podoplanin-positive MPM cell lines. In this study, we showed the antitumor effect of NZ-1, NZ-8, and NZ-12, a novel rat-human chimeric anti-human podoplanin antibody derived from NZ-1, in an MPM orthotopic xenograft SCID mouse model. Treatment with NZ-1 and rat NK (CD161a(+) ) cells inhibited the growth of tumors and the production of pleural effusion in NCI-H290/PDPN or NCI-H226 orthotopic xenograft mouse models. NZ-8 and human natural killer (NK) (CD56(+) ) cells also inhibited tumor growth and pleural effusion in MPM orthotopic xenograft mice. Furthermore, NZ-12 induced potent ADCC mediated by human MNC, compared with either NZ-1 or NZ-8. Antitumor effects were observed following treatment with NZ-12 and human NK (CD56(+) ) cells in MPM orthotopic xenograft mice. In addition, combined immunotherapy using the ADCC activity of NZ-12 mediated by human NK (CD56(+) ) cells with pemetrexed, led to enhanced antitumor effects in MPM orthotopic xenograft mice. These results strongly suggest that combination therapy with podoplanin-targeting immunotherapy using both NZ-12 and pemetrexed might provide an efficacious therapeutic strategy for the treatment of MPM. © 2016 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

  9. Multiple Beneficial Health Effects of Natural Alkylglycerols from Shark Liver Oil

    Directory of Open Access Journals (Sweden)

    Alain B. Legrand

    2010-07-01

    Full Text Available Alkylglycerols (alkyl-Gro are ether lipids abundant in the liver of some elasmobranch fish species such as ratfishes and some sharks. Shark liver oil from Centrophorus squamosus (SLO, or alkyl-Gro mix from this source, have several in vivo biological activities including stimulation of hematopoiesis and immunological defences, sperm quality improvement, or anti-tumor and anti-metastasis activities. Several mechanisms are suggested for these multiple activities, resulting from incorporation of alkyl-Gro into membrane phospholipids, and lipid signaling interactions. Natural alkyl-Gro mix from SLO contains several alkyl-Gro, varying by chain length and unsaturation. Six prominent constituents of natural alkyl-Gro mix, namely 12:0, 14:0, 16:0, 18:0, 16:1 n-7, and 18:1 n-9 alkyl-Gro, were synthesized and tested for anti-tumor and anti-metastatic activities on a model of grafted tumor in mice (3LL cells. 16:1 and 18:1 alkyl-Gro showed strong activity in reducing lung metastasis number, while saturated alkyl-Gro had weaker (16:0 or no (12:0, 14:0, 18:0 effect. Multiple compounds and mechanisms are probably involved in the multiple activities of natural alkyl-Gro.

  10. DNA strand scission by the novel antitumor antibiotic leinamycin

    International Nuclear Information System (INIS)

    Hara, Mitsunobu; Saitoh, Yutaka; Nakano, Hirofumi

    1990-01-01

    Leinamycin is a recently discovered antitumor antibiotic with an unusual 1,3-dioxo-1,2-dithiolane structure. It preferentially inhibits the incorporation of [ 3 H]thymidine into the acid-insoluble fraction of Bacillus subtilis. In vitro, leinamycin causes single-strand cleavage of supercoiled double-helical pBR322 DNA in the presence of thiol cofactors. Scavengers of oxygen radical did not suppress the DNA-cleaving activity. Thiol-activated leinamycin binds calf thymus DNA at 4 degree C and thermal treatment of the leinamycin-DNA adduct released a chemically modified leinamycin from the complex. The lack of cytotoxicity and DNA-cleaving activity for S-deoxyleinamycin indicates that the 1,3-dioxo-1,2-dithiolane moiety is essential for the activity of leinamycin. Thus, the primary cellular target of leinamycin appears to be DNA. It binds DNA and causes single-strand break at low concentrations, which may account for the potent antitumor activity

  11. [Establishment of human multidrug-resistant lung carcinoma cell line (D6/MVP)].

    Science.gov (United States)

    Ma, Sheng-lin; Feng, Jian-guo; Gu, Lin-hui; Ling, Yu-tian

    2003-03-01

    To establish human multidrug-resistant lung carcinoma cell line (D6/MVP) with its characteristics studied. Intermittent administration of high-dose MMC, VDS and DDP (MVP) was used to induce human lung carcinoma cell line (D6) to a multidrug-resistant variety (D6/MVP). MTT assay was used to study the multidrug resistance of D6/MVP to multianticarcinogen. Flow cytometry was used to study the cell cycle distribution and the expression of P-gp, multidrug resistance-associated protein (MRP) and GSH/GST. 1. D6/MVP was resistant to many anti-tumor agents, with the IC(50) 13.3 times higher and the drug resistance 2 - 6 times higher than D6, 2. The multiplication time of D6/MVP was prolonged and the cell number of S-phase decreased while that of G1- and G(2)-phase increased and 3. The expression of P-gp and MRP was enhanced significantly (96.2% vs 51.7%), but the expression of GSH/GST kept stable. D6/MVP is a multidrug-resistant cell line possessing the basic characteristics of drug-resistance.

  12. Testing Transgenic Aspen Plants with bar Gene for Herbicide Resistance under Semi-natural Conditions.

    Science.gov (United States)

    Lebedev, V G; Faskhiev, V N; Kovalenko, N P; Shestibratov, K A; Miroshnikov, A I

    2016-01-01

    Obtaining herbicide resistant plants is an important task in the genetic engineering of forest trees. Transgenic European aspen plants (Populus tremula L.) expressing the bar gene for phosphinothricin resistance have been produced using Agrobacterium tumefaciens-mediated transformation. Successful genetic transformation was confirmed by PCR analysis for thirteen lines derived from two elite genotypes. In 2014-2015, six lines were evaluated for resistance to herbicide treatment under semi-natural conditions. All selected transgenic lines were resistant to the herbicide Basta at doses equivalent to 10 l/ha (twofold normal field dosage) whereas the control plants died at 2.5 l/ha. Foliar NH4-N concentrations in transgenic plants did not change after treatment. Extremely low temperatures in the third ten-day period of October 2014 revealed differences in freeze tolerance between the lines obtained from Pt of f2 aspen genotypes. Stable expression of the bar gene after overwintering outdoors was confirmed by RT-PCR. On the basis of the tests, four transgenic aspen lines were selected. The bar gene could be used for retransformation of transgenic forest trees expressing valuable traits, such as increased productivity.

  13. Circumvention of Taxol-Resistance in Human Breast Cancers by Improved Water Soluble Taxanes

    Science.gov (United States)

    2001-10-01

    Basidomycetes were found to have antitumor activity in animal models, including one extract derived from Lentinus edodes which completely inhibited the growth...other naturally occurring polysaccharide preparations from Lentinus edodes , Ganoderma lucidum, and Aloe barbadensis Miller, like CPS, also demonstrated...1969) Inhibition of mouse sarcoma 180 by polysaccharides from Lentinus edodes (Berk.) sing. Nature 222:687- 688 8. Chen WC, Hau DM, Lee SS. (1995

  14. Identification of anti-CD98 antibody mimotopes for inducing antibodies with antitumor activity by mimotope immunization.

    Science.gov (United States)

    Saito, Misa; Kondo, Masahiro; Ohshima, Motohiro; Deguchi, Kazuki; Hayashi, Hideki; Inoue, Kazuyuki; Tsuji, Daiki; Masuko, Takashi; Itoh, Kunihiko

    2014-04-01

    A mimotope is an antibody-epitope-mimicking peptide retrieved from a phage display random peptide library. Immunization with antitumor antibody-derived mimotopes is promising for inducing antitumor immunity in hosts. In this study, we isolated linear and constrained mimotopes from HBJ127, a tumor-suppressing anti-CD98 heavy chain mAb, and determined their abilities for induction of antitumor activity equal to that of the parent antibody. We detected elevated levels of antipeptide responses, but failed to detect reactivity against native CD98-expressing HeLa cells in sera of immunized mice. Phage display panning and selection of mimotope-immunized mouse spleen-derived antibody Fab library showed that HeLa cell-reactive Fabs were successfully retrieved from the library. This finding indicates that native antigen-reactive Fab clones represented an undetectable minor population in mimotope-induced antibody repertoire. Functional and structural analysis of retrieved Fab clones revealed that they were almost identical to the parent antibody. From these results, we confirmed that mimotope immunization was promising for retrieving antitumor antibodies equivalent to the parent antibody, although the co-administration of adjuvant compounds such as T-cell epitope peptides and Toll-like receptor 4 agonist peptides is likely to be necessary for inducing stronger antitumor immunity than mimotope injection alone. © 2014 The Authors. Cancer Science published by Wiley Publishing Asia Pty Ltd on behalf of Japanese Cancer Association.

  15. Spin-labeled 1-alkyl-1-nitrosourea synergists of antitumor antibiotics.

    Science.gov (United States)

    Gadjeva, V; Koldamova, R

    2001-01-01

    A new method for synthesis of four spin-labeled structural analogues of the antitumor drug 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea (CCNU), using ethyl nitrite for nitrosation of the intermediate spin-labeled ureas has been described. In vitro synergistic effects of 1-ethyl-3-[4-(2,2,6,6-tetramethylpiperidine-1-oxyl)]-1-nitrosourea (3b) on the cytotoxicity of bleomycin and farmorubicin were found in human lymphoid leukemia tumor cells. We measured the tissue distribution of 3b in organ homogenates of C57BL mice by an electron paramagnetic resonance method. The spin-labeled nitrosourea was mainly localized in the lungs. Our results strongly support the development and validation of a new approach for synthesis of less toxic nitrosourea derivatives as potential synergists of antitumor drugs.

  16. Biochemical and histological evidences for the antitumor potential of ...

    African Journals Online (AJOL)

    Biochemical and histological evidences for the antitumor potential of Teucrium Oliverianum and Rhazya stricta in chemically-induced hepatocellular carcinoma. ... Photomicrograph of liver tissue sections of rats in HCC revealed hepatic parenchyma with foci of anaplastic hepatocellular carcinoma as well as other foci of ...

  17. Indicine-N-oxide: the antitumor principle of Heliotropium indicum.

    Science.gov (United States)

    Kugelman, M; Liu, W C; Axelrod, M; McBride, T J; Rao, K V

    1976-01-01

    Extracts of Heliotropium indicum Linn. (Boraginaceae) showed significant activity in several experimental tumor systems. The active principle is isolated and shown to be the N-oxide of the alkaloid, indicine, previously isolated from this plant. Supporting structural data and anti-tumor data are provided.

  18. Systematic screening of bryophytes for antitumor agents

    OpenAIRE

    Spjut, Richard W.; Kingston, David G. I.; Cassady, John M.

    1992-01-01

    References are made to cytotoxic and/or antitumor compounds that have been isolated - ansamitocin P-3 from Claopodium crispifolium (Hook.) Ren. & Card. and Anomodon attenuatus Hueb., or an associated actinomycete, and ohioensins and pallidisetums from Polytrichum spp. Several hundred collections, which have been obtained from temperate regions of North America during 1990 and 1991, are currently being screened in new bioassays; active sesquiterpene lactones have been recently isolated from sp...

  19. Ability of TEP1 in intestinal flora to modulate natural resistance of Anopheles dirus.

    Science.gov (United States)

    Wang, Yanyan; Wang, Ying; Zhang, Jingru; Xu, Wenyue; Zhang, Jian; Huang, Fu Sheng

    2013-08-01

    Blocking transmission of malaria is a reliable way to control and eliminate infection. However, in-depth knowledge of the interaction between Plasmodium and mosquito is needed. Studies suggest that innate immunity is the main mechanism inhibiting development of malaria parasites in the mosquito. Recent studies have found that use of antibiotics that inhibit the mosquito gut flora can reduce the immune response of Anopheles gambiae, thereby contributing to the development of malaria parasites. In our study, we used the non susceptible model of Anopheles dirus-Plasmodium yoelii to explore the effect of Anopheles intestinal flora on the natural resistance of A. dirus to P. yoelii. We found that in mosquitoes infected with Plasmodium, the intestinal flora can regulate expression of thioester-containing protein (TEP1) via an RNAi gene-silencing approach. Our results suggest that in the absence of TEP1, the natural microbiota cannot suppress the development of P. yoelii in A. dirus. This suggests that AdTEP1 plays an important role in the resistance of A. dirus to P. yoelii. The intestinal flora may modulate the development of P. yoelii in A. dirus by regulating TEP1 expression. Copyright © 2013 Elsevier Inc. All rights reserved.

  20. Transferrin receptor-targeted pH-sensitive micellar system for diminution of drug resistance and targetable delivery in multidrug-resistant breast cancer

    Directory of Open Access Journals (Sweden)

    Gao W

    2017-02-01

    Full Text Available Wei Gao,1 Guihua Ye,1 Xiaochuan Duan,1 Xiaoying Yang,1 Victor C Yang1,2 1Tianjin Key Laboratory on Technologies Enabling Development of Clinical Therapeutics and Diagnostics (Theranostics, School of Pharmacy, Tianjin Medical University, Tianjin, People’s Republic of China; 2Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan, Ann Arbor, MI, USA Abstract: The emergence of drug resistance is partially associated with overproduction of transferrin receptor (TfR. To overcome multidrug resistance (MDR and achieve tumor target delivery, we designed a novel biodegradable pH-sensitive micellar system modified with HAIYPRH, a TfR ligand (7pep. First, the polymers poly(l-histidine-coupled polyethylene glycol-2000 (PHIS-PEG2000 and 7pep-modified 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-polyethylene glycol-2000 (7pep-DSPE-PEG2000 were synthesized, and the mixed micelles were prepared by blending of PHIS-PEG2000 and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-polyethylene glycol-2000 (DSPE-PEG2000 or 7pep-DSPE-PEG2000 (7-pep HD micelles. The micelles exhibited good size uniformity, high encapsulation efficiency, and a low critical micelle concentration. By changing the polymer ratio in the micellar formulation, the pH response range was specially tailored to pH ~6.0. When loaded with antitumor drug doxorubicin (DOX, the micelle showed an acid pH-triggering drug release profile. The cellular uptake and cytotoxicity study demonstrated that 7-pep HD micelles could significantly enhance the intracellular level and antitumor efficacy of DOX in multidrug-resistant cells (MCF-7/Adr, which attributed to the synergistic effect of poly(l-histidine-triggered endolysosom escape and TfR-mediated endocytosis. Most importantly, the in vivo imaging study confirmed the targetability of 7-pep HD micelles to MDR tumor. These findings indicated that 7-pep HD micelles would be a promising drug delivery system in the treatment of drug-resistant

  1. Antitumor Effects of Saffron-Derived Carotenoids in Prostate Cancer Cell Models

    Directory of Open Access Journals (Sweden)

    Claudio Festuccia

    2014-01-01

    Full Text Available Crocus sativus L. extracts (saffron are rich in carotenoids. Preclinical studies have shown that dietary intake of carotenoids has antitumor effects suggesting their potential preventive and/or therapeutic roles. We have recently reported that saffron (SE and crocin (CR exhibit anticancer activity by promoting cell cycle arrest in prostate cancer (PCa cells. It has also been demonstrated that crocetin esters are produced after SE gastrointestinal digestion by CR hydrolysis. The aim of the present report was to investigate if SE, crocetin (CCT, and CR affected in vivo tumor growth of two aggressive PCa cell lines (PC3 and 22rv1 which were xenografted in male nude mice treated by oral gavage with SE, CR, and CCT. We demonstrated that the antitumor effects of CCT were higher when compared to CR and SE and treatments reverted the epithelial-mesenchymal transdifferentiation (EMT as attested by the significant reduction of N-cadherin and beta-catenin expression and the increased expression of E-cadherin. Additionally, SE, CR, and CCT inhibited PCa cell invasion and migration through the downmodulation of metalloproteinase and urokinase expression/activity suggesting that these agents may affect metastatic processes. Our findings suggest that CR and CCT may be dietary phytochemicals with potential antitumor effects in biologically aggressive PCa cells.

  2. Properties of realgar bioleaching using an extremely acidophilic bacterium and its antitumor mechanism as an anticancer agent

    Directory of Open Access Journals (Sweden)

    Peng Chen

    Full Text Available Abstract Realgar is a naturally occurring arsenic sulfide (or Xionghuang, in Chinese. It contains over 90% tetra-arsenic tetrasulfide (As4S4. Currently, realgar has been confirmed the antitumor activities, both in vitro and in vivo, of realgar extracted using Acidithiobacillus ferrooxidans (A. ferrooxidans. Bioleaching, a new technology to greatly improve the use rate of arsenic extraction from realgar using bacteria, is a novel methodology that addressed a limitation of the traditional method for realgar preparation. The present systematic review reports on the research progress in realgar bioleaching and its antitumor mechanism as an anticancer agent. A total of 93 research articles that report on the biological activity of extracts from realgar using bacteria and its preparation were presented in this review. The realgar bioleaching solution (RBS works by inducing apoptosis when it is used to treat tumor cells in vitro and in vivo. When it is used to treat animal model organisms in vivo, such as mice and Caenorhabditis elegans, tumor tissues grew more slowly, with mass necrosis. Meanwhile, the agent also showed obvious inhibition of tumor cell growth. Bioleaching technology greatly improves the utilization of realgar and is a novel methodology to improve the traditional method.

  3. Randomized, Double-Blind, Phase III Trial of Ipilimumab Versus Placebo in Asymptomatic or Minimally Symptomatic Patients With Metastatic Chemotherapy-Naive Castration-Resistant Prostate Cancer

    DEFF Research Database (Denmark)

    Beer, Tomasz M; Kwon, Eugene D; Drake, Charles G

    2017-01-01

    Purpose Ipilimumab increases antitumor T-cell responses by binding to cytotoxic T-lymphocyte antigen 4. We evaluated treatment with ipilimumab in asymptomatic or minimally symptomatic patients with chemotherapy-naive metastatic castration-resistant prostate cancer without visceral metastases. Pat...

  4. Naturally selected honey bee (Apis mellifera) colonies resistant to Varroa destructor do not groom more intensively

    NARCIS (Netherlands)

    Kruitwagen, Astrid; Langevelde, van Frank; Dooremalen, van Coby; Blacquière, Tjeerd

    2017-01-01

    The ectoparasitic mite Varroa destructor is an important cause of high colony losses of the honey bee Apis mellifera. In The Netherlands, two resistant A. mellifera populations developed naturally after ceasing varroa control. As a result, mite infestation levels of the colonies of these populations

  5. Enhancement of intrinsic antitumor activity in spore-endotoxin mixtures of Bacillus thuringiensis by exposure to ultraviolet radiation

    Energy Technology Data Exchange (ETDEWEB)

    Zamola, B; Karminski-Zamola, G; Fuks, Z; Kubovic, M [Zagreb Univ. (Yugoslavia); Wrishcer, M [Institut Rudjer Boskovic, Zagreb (Yugoslavia)

    1985-03-01

    Irradiation of spore-endotoxin mixtures from Bacillus thuringiensis cultures at 254 nm (60 ..mu..W cm/sup -2/) enhances their intrinsic antitumor potency as well as that of either component. The extent of enhancement depends on the length of exposure (optimum: 35 min) and may thus be due to photochemical changes of the endotoxin protein or/and to photoproduction of additional compounds with antitumor activity. Antitumor effects, expressed as survival rates of C57BL/6 mice inoculated with Lewis' mouse lung carcinoma and subjected to treatments 24 h later, depended on the number of doses of preparations administered (mixture, separated components).

  6. Mechanisms of Intrinsic Tumor Resistance to Immunotherapy

    Directory of Open Access Journals (Sweden)

    John Rieth

    2018-05-01

    Full Text Available An increased understanding of the interactions between the immune system and tumors has opened the door to immunotherapy for cancer patients. Despite some success with checkpoint inhibitors including ipilimumab, pembrolizumab, and nivolumab, most cancer patients remain unresponsive to such immunotherapy, likely due to intrinsic tumor resistance. The mechanisms most likely involve reducing the quantity and/or quality of antitumor lymphocytes, which ultimately are driven by any number of developments: tumor mutations and adaptations, reduced neoantigen generation or expression, indoleamine 2,3-dioxygenase (IDO overexpression, loss of phosphatase and tensin homologue (PTEN expression, and overexpression of the Wnt–β-catenin pathway. Current work in immunotherapy continues to identify various tumor resistance mechanisms; future work is needed to develop adjuvant treatments that target those mechanisms, in order to improve the efficacy of immunotherapy and to expand its scope.

  7. Aspirin regulation of c-myc and cyclinD1 proteins to overcome tamoxifen resistance in estrogen receptor-positive breast cancer cells.

    Science.gov (United States)

    Cheng, Ran; Liu, Ya-Jing; Cui, Jun-Wei; Yang, Man; Liu, Xiao-Ling; Li, Peng; Wang, Zhan; Zhu, Li-Zhang; Lu, Si-Yi; Zou, Li; Wu, Xiao-Qin; Li, Yu-Xia; Zhou, You; Fang, Zheng-Yu; Wei, Wei

    2017-05-02

    Tamoxifen is still the most commonly used endocrine therapy drug for estrogen receptor (ER)-positive breast cancer patients and has an excellent outcome, but tamoxifen resistance remains a great impediment to successful treatment. Recent studies have prompted an anti-tumor effect of aspirin. Here, we demonstrated that aspirin not only inhibits the growth of ER-positive breast cancer cell line MCF-7, especially when combined with tamoxifen, but also has a potential function to overcome tamoxifen resistance in MCF-7/TAM. Aspirin combined with tamoxifen can down regulate cyclinD1 and block cell cycle in G0/G1 phase. Besides, tamoxifen alone represses c-myc, progesterone receptor (PR) and cyclinD1 in MCF-7 cell line but not in MCF-7/TAM, while aspirin combined with tamoxifen can inhibit the expression of these proteins in the resistant cell line. When knocking down c-myc in MCF-7/TAM, cells become more sensitive to tamoxifen, cell cycle is blocked as well, indicating that aspirin can regulate c-myc and cyclinD1 proteins to overcome tamoxifen resistance. Our study discovered a novel role of aspirin based on its anti-tumor effect, and put forward some kinds of possible mechanisms of tamoxifen resistance in ER-positive breast cancer cells, providing a new strategy for the treatment of ER-positive breast carcinoma.

  8. Natural CD8+25+ regulatory T cell-secreted exosomes capable of suppressing cytotoxic T lymphocyte-mediated immunity against B16 melanoma

    International Nuclear Information System (INIS)

    Xie, Yufeng; Zhang, Xueshu; Zhao, Tuo; Li, Wei; Xiang, Jim

    2013-01-01

    Highlights: •CD8 + 25 + regulatory T cells secrete tolerogenic exosomes. •CD8 + 25 + regulatory T cell-derived exosomes exhibit immunosuppressive effect. •CD8 + 25 + regulatory T cell-derived exosomes inhibit antitumor immunity. -- Abstract: Natural CD4 + 25 + and CD8 + 25 + regulatory T (Tr) cells have been shown to inhibit autoimmune diseases. Immune cells secrete exosomes (EXOs), which are crucial for immune regulation. However, immunomodulatory effect of natural Tr cell-secreted EXOs is unknown. In this study, we purified natural CD8 + 25 + Tr cells from C57BL/6 mouse naive CD8 + T cells, and in vitro amplified them with CD3/CD28 beads. EXOs (EXO Tr ) were purified from Tr cell’s culture supernatants by differential ultracentrifugation and analyzed by electron microscopy, Western blot and flow cytometry. Our data showed that EXO Tr had a “saucer” or round shape with 50–100 nm in diameter, contained EXO-associated markers LAMP-1 and CD9, and expressed natural Tr cell markers CD25 and GITR. To assess immunomodulatory effect, we i.v. immunized C57BL/6 mice with ovalbumin (OVA)-pulsed DCs (DC OVA ) plus Tr cells or EXO Tr , and then assessed OVA-specific CD8 + T cell responses using PE-H-2K b /OVA tetramer and FITC-anti-CD8 antibody staining by flow cytometry and antitumor immunity in immunized mice with challenge of OVA-expressing BL6–10 OVA melanoma cells. We demonstrated that DC OVA -stimulated CD8 + T cell responses and protective antitumor immunity significantly dropped from 2.52% to 1.08% and 1.81% (p OVA (p Tr , respectively. Our results indicate that natural CD8 + 25 + Tr cell-released EXOs, alike CD8 + 25 + Tr cells, can inhibit CD8 + T cell responses and antitumor immunity. Therefore, EXOs derived from natural CD4 + 25 + and CD8 + 25 + Tr cells may become an alternative for immunotherapy of autoimmune diseases

  9. Targeting Sonic Hedgehog Signaling by Compounds and Derivatives from Natural Products

    Directory of Open Access Journals (Sweden)

    Yu-Chuen Huang

    2013-01-01

    Full Text Available Cancer stem cells (CSCs are a major cause of cancer treatment failure, relapse, and drug resistance and are known to be responsible for cancer cell invasion and metastasis. The Sonic hedgehog (Shh signaling pathway is crucial to embryonic development. Intriguingly, the aberrant activation of the Shh pathway plays critical roles in developing CSCs and leads to angiogenesis, migration, invasion, and metastasis. Natural compounds and chemical structure modified derivatives from complementary and alternative medicine have received increasing attention as cancer chemopreventives, and their antitumor effects have been demonstrated both in vitro and in vivo. However, reports for their bioactivity against CSCs and specifically targeting Shh signaling remain limited. In this review, we summarize investigations of the compounds cyclopamine, curcumin, epigallocatechin-3-gallate, genistein, resveratrol, zerumbone, norcantharidin, and arsenic trioxide, with a focus on Shh signaling blockade. Given that Shh signaling antagonism has been clinically proven as effective strategy against CSCs, this review may be exploitable for development of novel anticancer agents from complementary and alternative medicine.

  10. Identification, characterization and potent antitumor activity of ECO-4601, a novel peripheral benzodiazepine receptor ligand.

    Science.gov (United States)

    Gourdeau, Henriette; McAlpine, James B; Ranger, Maxime; Simard, Bryan; Berger, Francois; Beaudry, Francis; Farnet, Chris M; Falardeau, Pierre

    2008-05-01

    ECO-4601 is a structurally novel farnesylated dibenzodiazepinone discovered through DECIPHER technology, Thallion's proprietary drug discovery platform. The compound was shown to have a broad cytotoxic activity in the low micromolar range when tested in the NCI 60 cell line panel. In the work presented here, ECO-4601 was further evaluated against brain tumor cell lines. Preliminary mechanistic studies as well as in vivo antitumor evaluation were performed. Since ECO-4601 has a benzodiazepinone moiety, we first investigated if it binds the central and/or peripheral benzodiazepine receptors. ECO-4601 was tested in radioligand binding assays on benzodiazepine receptors obtained from rat hearts. The ability of ECO-4601 to inhibit the growth of CNS cancers was evaluated on a panel of mouse, rat and human glioma cell lines using a standard MTT assay. Antitumor efficacy studies were performed on gliomas (rat and human), human breast and human prostate mouse tumor xenografts. Antitumor activity and pharmacokinetic analysis of ECO-4601 was evaluated following intravenous (i.v.), subcutaneous (s.c.), and intraperitoneal (i.p.) bolus administrations. ECO-4601 was shown to bind the peripheral but not the central benzodiazepine receptor and inhibited the growth of CNS tumor cell lines. Bolus s.c. and i.p. administration gave rise to low but sustained drug exposure, and resulted in moderate to significant antitumor activity at doses that were well tolerated. In a rat glioma (C6) xenograft model, ECO-4601 produced up to 70% tumor growth inhibition (TGI) while in a human glioma (U-87MG) xenograft, TGI was 34%. Antitumor activity was highly significant in both human hormone-independent breast (MDA-MB-231) and prostate (PC-3) xenografts, resulting in TGI of 72 and 100%, respectively. On the other hand, i.v. dosing was followed by rapid elimination of the drug and was ineffective. Antitumor efficacy of ECO-4601 appears to be associated with the exposure parameter AUC and/or sustained

  11. Using Natural Products to Treat Resistant and Persistent Bacterial Infections

    Science.gov (United States)

    Deering, Robert W.

    Antimicrobial resistance is a growing threat to human health both worldwide and in the United States. Most concerning is the emergence of multi-drug resistant (MDR) bacterial pathogens, especially the 'ESKAPE' pathogens for which treatment options are dwindling. To complicate the problem, approvals of antibiotic drugs are extremely low and many research and development efforts in the pharmaceutical industry have ceased, leaving little certainty that critical new antibiotics are nearing the clinic. New antibiotics are needed to continue treating these evolving infections. In addition to antibiotics, approaches that aim to inhibit or prevent antimicrobial resistance could be useful. Also, studies that improve our understanding of bacterial pathophysiology could lead to new therapies for infectious disease. Natural products, especially those from the microbial world, have been invaluable as resources for new antibacterial compounds and as insights into bacterial physiology. The goal of this dissertation is to find new ways to treat resistant bacterial infections and learn more about the pathophysiology of these bacteria. Investigations of natural products to find molecules able to be used as new antibiotics or to modulate resistance and other parts of bacterial physiology are crucial aspects of the included studies. The first included study, which is reported in chapter two, details a chemical investigation of a marine Pseudoalteromonas sp. Purification efforts of the microbial metabolites were guided by testing against a resistance nodulation of cell division model of efflux pumps expressed in E. coli. These pumps play an important role in the resistance of MDR Gram negative pathogens such as Pseudomonas aeruginosa and Enterobacteriaceae. Through this process, 3,4-dibromopyrrole-2,5-dione was identified as a potent inhibitor of the RND efflux pumps and showed synergistic effects against the E. coli strain with common antibiotics including fluoroquinolones, beta

  12. Evaluation of the antitumor effects of vitamin K2 (menaquinone-7) nanoemulsions modified with sialic acid-cholesterol conjugate.

    Science.gov (United States)

    Shi, Jia; Zhou, Songlei; Kang, Le; Ling, Hu; Chen, Jiepeng; Duan, Lili; Song, Yanzhi; Deng, Yihui

    2018-02-01

    Numerous studies have recently shown that vitamin K 2 (VK 2 ) has antitumor effects in a variety of tumor cells, but there are few reports demonstrating antitumor effects of VK 2 in vivo. The antitumor effects of VK 2 in nanoemulsions are currently not known. Therefore, we sought to characterize the antitumor potential of VK 2 nanoemulsions in S180 tumor cells in the present study. Furthermore, a ligand conjugate sialic acid-cholesterol, with enhanced affinity towards the membrane receptors overexpressed in tumors, was anchored on the surface of the nanoemulsions to increase VK 2 distribution to the tumor tissue. VK 2 was encapsulated in oil-in-water nanoemulsions, and the physical and chemical stability of the nanoemulsions were characterized during storage at 25 °C. At 25 °C, all nanoemulsions remained physically and chemically stable with little change in particle size. An in vivo study using syngeneic mice with subcutaneously established S180 tumors demonstrated that intravenous or intragastric administration of VK 2 nanoemulsions significantly suppressed the tumor growth. The VK 2 nanoemulsions modified with sialic acid-cholesterol conjugate showed higher tumor growth suppression than the VK 2 nanoemulsions, while neither of them exhibited signs of drug toxicity. In summary, VK 2 exerted effective antitumor effects in vivo, and VK 2 nanoemulsions modified with sialic acid-cholesterol conjugate enhanced the antitumor activity, suggesting that these VK 2 may be promising agents for the prevention or treatment of tumor in patients.

  13. Synergistic antitumor effect of 3-bromopyruvate and 5-fluorouracil against human colorectal cancer through cell cycle arrest and induction of apoptosis.

    Science.gov (United States)

    Chong, Dianlong; Ma, Linyan; Liu, Fang; Zhang, Zhirui; Zhao, Surong; Huo, Qiang; Zhang, Pei; Zheng, Hailun; Liu, Hao

    2017-09-01

    3-Bromopyruvic acid (3-BP) is a well-known inhibitor of energy metabolism. It has been proposed as an anticancer agent as well as a chemosensitizer for use in combination with anticancer drugs. 5-Fluorouracil (5-FU) is the first-line chemotherapeutic agent for colorectal cancer; however, most patients develop resistance to 5-FU through various mechanisms. The aim of this study was to investigate whether 3-BP has a synergistic antitumor effect with 5-FU on human colorectal cancer cells. In our study, combined 3-BP and 5-FU treatment upregulated p53 and p21, whereas cyclin-dependent kinase CDK4 and CDK2 were downregulated, which led to G0/G1 phase arrest. Furthermore, there was an increase in reactive oxygen species levels and a decrease in adenosine triphosphate levels. It was also observed that Bax expression increased, whereas Bcl-2 expression reduced, which were indicative of mitochondria-dependent apoptosis. In addition, the combination of 3-BP and 5-FU significantly suppressed tumor growth in the BALB/c mice in vivo. Therefore, 3-BP inhibits tumor proliferation and induces S and G2/M phase arrest. It also exerts a synergistic antitumor effect with 5-FU on SW480 cells.

  14. Silybin-mediated inhibition of Notch signaling exerts antitumor activity in human hepatocellular carcinoma cells.

    Directory of Open Access Journals (Sweden)

    Song Zhang

    Full Text Available Hepatocellular carcinoma (HCC is a global health burden that is associated with limited treatment options and poor patient prognoses. Silybin (SIL, an antioxidant derived from the milk thistle plant (Silybum marianum, has been reported to exert hepatoprotective and antitumorigenic effects both in vitro and in vivo. While SIL has been shown to have potent antitumor activity against various types of cancer, including HCC, the molecular mechanisms underlying the effects of SIL remain largely unknown. The Notch signaling pathway plays crucial roles in tumorigenesis and immune development. In the present study, we assessed the antitumor activity of SIL in human HCC HepG2 cells in vitro and in vivo and explored the roles of the Notch pathway and of the apoptosis-related signaling pathway on the activity of SIL. SIL treatment resulted in a dose- and time-dependent inhibition of HCC cell viability. Additionally, SIL exhibited strong antitumor activity, as evidenced not only by reductions in tumor cell adhesion, migration, intracellular glutathione (GSH levels and total antioxidant capability (T-AOC but also by increases in the apoptotic index, caspase3 activity, and reactive oxygen species (ROS. Furthermore, SIL treatment decreased the expression of the Notch1 intracellular domain (NICD, RBP-Jκ, and Hes1 proteins, upregulated the apoptosis pathway-related protein Bax, and downregulated Bcl2, survivin, and cyclin D1. Notch1 siRNA (in vitro or DAPT (a known Notch1 inhibitor, in vivo further enhanced the antitumor activity of SIL, and recombinant Jagged1 protein (a known Notch ligand in vitro attenuated the antitumor activity of SIL. Taken together, these data indicate that SIL is a potent inhibitor of HCC cell growth that targets the Notch signaling pathway and suggest that the inhibition of Notch signaling may be a novel therapeutic intervention for HCC.

  15. Detection of the acetylcholinesterase insecticide resistance mutation (G328A) in natural populations of Ceratitis capitata

    International Nuclear Information System (INIS)

    Elfekih, Samia; Haran, Julien; Shannon, Matthew; Vogler, Alfried P.

    2015-01-01

    Wild Mediterranean fruit fly specimens collected from various regions worldwide were screened for the glycine to alanine (Gly->Ala) point mutation (G328A) in the acetylcholinesterase enzyme, presumably causing resistance to organophosphates. We found that the single nucleotide polymorphism (SNP) responsible for this amino acid change is located at the beginning of exon 6 of the Ccace2 gene. The identification of the exact location of the SNP permitted PCR primer design around this site and direct sequencing of the corresponding genomic region. We detected the resistance allele in natural Mediterranean fruit fly populations from Brazil and Spain, but not from other sites in four continents. The known treatment history of sites suggests that the resistance build up is linked to organophosphate application in the held. The PCR-based detection provides a screening method useful for monitoring Mediterranean fruit fly insecticide resistance in local populations and improving pest management strategies accordingly. (author)

  16. In Vitro Antitumor Activity of Sesquiterpene Lactones from Lychnophora trichocarpha

    Directory of Open Access Journals (Sweden)

    D.A. Saúde-Guimarães

    2014-06-01

    Full Text Available The sesquiterpene lactones lychnopholide and eremantholide C were isolated from Lychnophora trichocarpha Spreng. (Asteraceae, which is a plant species native to the Brazilian Savannah or Cerrado and popularly known as arnica. Sesquiterpene lactones are known to present a variety of biological activities including antitumor activity. The present paper reports on the evaluation of the in vitro antitumor activity of lychnopholide and eremantholide C, in the National Cancer Institute, USA (NCI, USA, against a panel of 52 human tumor cell lines of major human tumors derived from nine cancer types. Lychnopholide disclosed significant activity against 30 cell lines of seven cancer types with IC100 (total growth concentration inhibition values between 0.41 µM and 2.82 µM. Eremantholide C showed significant activity against 30 cell lines of eight cancer types with IC100 values between 21.40 µM and 53.70 µM. Lychnopholide showed values of lethal concentration 50% (LC50 for 30 human tumor cell lines between 0.72 and 10.00 µM, whereas eremantholide C presented values of LC50 for 21 human tumor cell lines between 52.50 and 91.20 µM. Lychnopholide showed an interesting profile of antitumor activity. The α-methylene-γ-lactone present in the structure of lychnopholide, besides two α,β- unsaturated carbonyl groups, might be responsible for the better activity and higher cytotoxicity of this compound in relation to eremantholide C.

  17. Rocaglamide overcomes tumor necrosis factor-related apoptosis-inducing ligand resistance in hepatocellular carcinoma cells by attenuating the inhibition of caspase-8 through cellular FLICE-like-inhibitory protein downregulation.

    Science.gov (United States)

    Luan, Zhou; He, Ying; He, Fan; Chen, Zhishui

    2015-01-01

    The enhancement of apoptosis is a therapeutic strategy used in the treatment of cancer. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a promising antitumor agent. However, hepatocellular carcinoma (HCC) cells exhibit marked resistance to the induction of cell death by TRAIL. The present study investigated whether rocaglamide, a naturally occurring product isolated from the genus Aglaia, is able to sensitize resistant HCC cells to TRAIL-mediated apoptosis. Two HCC cell lines, HepG2 and Huh-7, were treated with rocaglamide and/or TRAIL and the induction of apoptosis and effects on the TRAIL signaling pathway were investigated. The in vivo efficacy of rocaglamide was determined in TRAIL-resistant Huh-7-derived tumor xenografts. Rocaglamide significantly sensitized the TRAIL-resistant HCC cells to apoptosis by TRAIL, which resulted from the rocaglamide-mediated downregulation of cellular FLICE-like inhibitory protein and subsequent caspase-8 activation. Furthermore, rocaglamide markedly inhibited tumor growth from Huh-7 cells propagated in severe combined immunodeficient mice, suggesting that chemosentization also occurred in vivo. These data suggest that rocaglamide acted synergistically with TRAIL against the TRAIL-resistant HCC cells. Thus, it is concluded that rocaglamide as an adjuvant to TRAIL-based therapy may present a promising therapeutic approach for the treatment of HCC.

  18. Regulatory T cells as suppressors of anti-tumor immunity: Role of metabolism.

    Science.gov (United States)

    De Rosa, Veronica; Di Rella, Francesca; Di Giacomo, Antonio; Matarese, Giuseppe

    2017-06-01

    Novel concepts in immunometabolism support the hypothesis that glucose consumption is also used to modulate anti-tumor immune responses, favoring growth and expansion of specific cellular subsets defined in the past as suppressor T cells and currently reborn as regulatory T (Treg) cells. During the 1920s, Otto Warburg and colleagues observed that tumors consumed high amounts of glucose compared to normal tissues, even in the presence of oxygen and completely functioning mitochondria. However, the role of the Warburg Effect is still not completely understood, particularly in the context of an ongoing anti-tumor immune response. Current experimental evidence suggests that tumor-derived metabolic restrictions can drive T cell hyporesponsiveness and immune tolerance. For example, several glycolytic enzymes, deregulated in cancer, contribute to tumor progression independently from their canonical metabolic activity. Indeed, they can control apoptosis, gene expression and activation of specific intracellular pathways, thus suggesting a direct link between metabolic switches and pro-tumorigenic transcriptional programs. Focus of this review is to define the specific metabolic pathways controlling Treg cell immunobiology in the context of anti-tumor immunity and tumor progression. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Experimental study on anti-tumor effect of pcEgr-IFNγ gene-radiotherapy

    International Nuclear Information System (INIS)

    Wu Congmei; Li Xiuyi; Liu Shuzheng

    2001-01-01

    Objective: To study the anti-tumor effect of IFN γ gene-radiotherapy to murine melanoma and its immunologic mechanism. Methods: pcEgr-IFNγ plasmids were injected locally into tumor, and 36 hours later, the tumors were given 20 Gy X-ray irradiation. Tumor growth at different time, IFN γ expression 3 days later and immunologic indexes 15 days later were detected. Results: At 3-15 days after pcEgr-IFNγ gene-radiotherapy, the tumor growth rate was lower than that of irradiation alone group. It was also lower than that of gene therapy alone group and control plasmid combined with X-ray irradiation group significantly. Day 3 tumor IFN γ expression was higher than that of plasmid treatment alone group. NK activity, IL-2 and IFN γ secretion activities were higher than those of gene therapy alone and irradiation alone groups significantly. Conclusion: The antitumor effect of IFN γ gene-radiotherapy is better than that of either of them applied solely. Its mechanism might be concerned with the higher expression of IFN γ induced by irradiation in tumors and activation of anti-tumor immunologic functions

  20. PEGylation of α-momorcharin retained its anti-tumor activity with ...

    African Journals Online (AJOL)

    user

    the anti-tumor activity of α-MMC-PEG decreased by about 30% in vitro. This sensitivity increase of 50 ... experiments and were acclimatized in the animal room. They were housed on aspen ..... PEGylation, successful approach to drug delivery.

  1. Does human activity impact the natural antibiotic resistance background? Abundance of antibiotic resistance genes in 21 Swiss lakes.

    Science.gov (United States)

    Czekalski, Nadine; Sigdel, Radhika; Birtel, Julia; Matthews, Blake; Bürgmann, Helmut

    2015-08-01

    Antibiotic resistance genes (ARGs) are emerging environmental contaminants, known to be continuously discharged into the aquatic environment via human and animal waste. Freshwater aquatic environments represent potential reservoirs for ARG and potentially allow sewage-derived ARG to persist and spread in the environment. This may create increased opportunities for an eventual contact with, and gene transfer to, human and animal pathogens via the food chain or drinking water. However, assessment of this risk requires a better understanding of the level and variability of the natural resistance background and the extent of the human impact. We have analyzed water samples from 21 Swiss lakes, taken at sampling points that were not under the direct influence of local contamination sources and analyzed the relative abundance of ARG using quantitative real-time PCR. Copy numbers of genes mediating resistance to three different broad-spectrum antibiotic classes (sulfonamides: sul1, sul2, tetracyclines: tet(B), tet(M), tet(W) and fluoroquinolones: qnrA) were normalized to copy numbers of bacterial 16S rRNA genes. We used multiple linear regression to assess if ARG abundance is related to human activities in the catchment, microbial community composition and the eutrophication status of the lakes. Sul genes were detected in all sampled lakes, whereas only four lakes contained quantifiable numbers of tet genes, and qnrA remained below detection in all lakes. Our data indicate higher abundance of sul1 in lakes with increasing number and capacity of wastewater treatment plants (WWTPs) in the catchment. sul2 abundance was rather related to long water residence times and eutrophication status. Our study demonstrates the potential of freshwater lakes to preserve antibiotic resistance genes, and provides a reference for ARG abundance from lake systems with low human impact as a baseline for assessing ARG contamination in lake water. Copyright © 2015 Elsevier Ltd. All rights

  2. A novel combination of TRAIL and doxorubicin enhances antitumor effect based on passive tumor-targeting of liposomes

    International Nuclear Information System (INIS)

    Guo Liangran; Fan Li; Ren Jinfeng; Pang Zhiqing; Ren Yulong; Li Jingwei; Jiang Xinguo; Wen Ziyi

    2011-01-01

    Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a novel anticancer agent for non-small cell lung cancer (NSCLC). However, approximately half of NSCLC cell lines are highly resistant to TRAIL. Doxorubicin (DOX) can sensitize NSCLC cells to TRAIL-induced apoptosis, indicating the possibility of combination therapy. Unfortunately, the therapeutic effect of a DOX and TRAIL combination is limited by multiple factors including the short serum half-life of TRAIL, poor compliance and application difficulty in the clinic, chronic DOX-induced cardiac toxicity, and the multidrug resistance (MDR) property of NSCLC cells. To solve such problems, we developed the combination of TRAIL liposomes (TRAIL-LP) and DOX liposomes (DOX-LP). An in vitro cytotoxicity study indicated that DOX-LP sensitized the NSCLC cell line A-549 to TRAIL-LP-induced apoptosis. Furthermore, this combination therapy of TRAIL-LP and DOX-LP displayed a stronger antitumor effect on NSCLC in xenografted mice when compared with free drugs or liposomal drugs alone. Therefore, the TRAIL-LP and DOX-LP combination therapy has excellent potential to become a new therapeutic approach for patients with advanced NSCLC.

  3. GE11 Peptide as an Active Targeting Agent in Antitumor Therapy: A Minireview

    Directory of Open Access Journals (Sweden)

    Ida Genta

    2017-12-01

    Full Text Available A lot of solid tumors are characterized by uncontrolled signal transduction triggered by receptors related to cellular growth. The targeting of these cell receptors with antitumor drugs is essential to improve chemotherapy efficacy. This can be achieved by conjugation of an active targeting agent to the polymer portion of a colloidal drug delivery system loaded with an antitumor drug. The goal of this minireview is to report and discuss some recent results in epidermal growth factor receptor targeting by the GE11 peptide combined with colloidal drug delivery systems as smart carriers for antitumor drugs. The minireview chapters will focus on explaining and discussing: (i Epidermal growth factor receptor (EGFR structures and functions; (ii GE11 structure and biologic activity; (iii examples of GE11 conjugation and GE11-conjugated drug delivery systems. The rationale is to contribute in gathering information on the topic of active targeting to tumors. A case study is introduced, involving research on tumor cell targeting by the GE11 peptide combined with polymer nanoparticles.

  4. Study of Antitumor Activity of Sodium Phenylbutyrate, Histon Deacetylase Inhibitor, on Ehrlich Carcinoma Model.

    Science.gov (United States)

    Fadeev, N P; Kharisov, R I; Kovan'ko, E G; Pustovalov, Yu I

    2015-09-01

    Antitumor activity of sodium phenylbutyrate was studied on 120 outbred female mice with transplanted Ehrlich ascites carcinoma. The animals received the drug in doses of 400, 800, and 1200 mg/kg with drinking water daily for 21 days. The antitumor effect was evaluated by tumor growth inhibition and lifespan prolongation. Phenylbutyrate in the dose of 800 mg/kg was most effective. The drug inhibited the tumor growth by 71%, prolonged the lifespan of animals by 28, and was low-toxic.

  5. Oleanolic and maslinic acid sensitize soft tissue sarcoma cells to doxorubicin by inhibiting the multidrug resistance protein MRP-1, but not P-glycoprotein.

    Science.gov (United States)

    Villar, Victor Hugo; Vögler, Oliver; Barceló, Francisca; Gómez-Florit, Manuel; Martínez-Serra, Jordi; Obrador-Hevia, Antònia; Martín-Broto, Javier; Ruiz-Gutiérrez, Valentina; Alemany, Regina

    2014-04-01

    The pentacyclic triterpenes oleanolic acid (OLA) and maslinic acid (MLA) are natural compounds present in many plants and dietary products consumed in the Mediterranean diet (e.g., pomace and virgin olive oils). Several nutraceutical activities have been attributed to OLA and MLA, whose antitumoral effects have been extensively evaluated in human adenocarcinomas, but little is known regarding their effectiveness in soft tissue sarcomas (STS). We assessed efficacy and molecular mechanisms involved in the antiproliferative effects of OLA and MLA as single agents or in combination with doxorubicin (DXR) in human synovial sarcoma SW982 and leiomyosarcoma SK-UT-1 cells. As single compound, MLA (10-100 μM) was more potent than OLA, inhibiting the growth of SW982 and SK-UT-1 cells by 70.3 ± 1.11% and 68.8 ± 1.52% at 80 μM, respectively. Importantly, OLA (80 μM) or MLA (30 μM) enhanced the antitumoral effect of DXR (0.5-10 μM) by up to 2.3-fold. On the molecular level, efflux activity of the multidrug resistance protein MRP-1, but not of the P-glycoprotein, was inhibited. Most probably as a consequence, DXR accumulated in these cells. Kinetic studies showed that OLA behaved as a competitive inhibitor of substrate-mediated MRP-1 transport, whereas MLA acted as a non-competitive one. Moreover, none of both triterpenes induced a compensatory increase in MRP-1 expression. In summary, OLA or MLA sensitized cellular models of STS to DXR and selectively inhibited MRP-1 activity, but not its expression, leading to a higher antitumoral effect possibly relevant for clinical treatment. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. Targeting Gene-Viro-Therapy with AFP driving Apoptin gene shows potent antitumor effect in hepatocarcinoma

    Directory of Open Access Journals (Sweden)

    Zhang Kang-Jian

    2012-02-01

    Full Text Available Abstract Background Gene therapy and viral therapy are used for cancer therapy for many years, but the results are less than satisfactory. Our aim was to construct a new recombinant adenovirus which is more efficient to kill hepatocarcinoma cells but more safe to normal cells. Methods By using the Cancer Targeting Gene-Viro-Therapy strategy, Apoptin, a promising cancer therapeutic gene was inserted into the double-regulated oncolytic adenovirus AD55 in which E1A gene was driven by alpha fetoprotein promoter along with a 55 kDa deletion in E1B gene to form AD55-Apoptin. The anti-tumor effects and safety were examined by western blotting, virus yield assay, real time polymerase chain reaction, 3-(4,5-dimethylthiazol-2-yl-2, 5-diphenyltetrazolium bromide assay, Hoechst33342 staining, Fluorescence-activated cell sorting, xenograft tumor model, Immunohistochemical assay, liver function analysis and Terminal deoxynucleotidyl transferase mediated dUTP Nick End Labeling assay. Results The recombinant virus AD55-Apoptin has more significant antitumor effect for hepatocelluar carcinoma cell lines (in vitro than that of AD55 and even ONYX-015 but no or little impair on normal cell lines. Furthermore, it also shows an obvious in vivo antitumor effect on the Huh-7 liver carcinoma xenograft in nude mice with bigger beginning tumor volume till about 425 mm3 but has no any damage on the function of liver. The induction of apoptosis is involved in AD55-Apoptin induced antitumor effects. Conclusion The AD55-Apoptin can be a potential anti-hepatoma agent with remarkable antitumor efficacy as well as higher safety in cancer targeting gene-viro-therapy system.

  7. A novel, polymer-coated oncolytic measles virus overcomes immune suppression and induces robust antitumor activity

    Directory of Open Access Journals (Sweden)

    Kaname Nosaki

    2016-01-01

    Full Text Available Although various therapies are available to treat cancers, including surgery, chemotherapy, and radiotherapy, cancer has been the leading cause of death in Japan for the last 30 years, and new therapeutic modalities are urgently needed. As a new modality, there has recently been great interest in oncolytic virotherapy, with measles virus being a candidate virus expected to show strong antitumor effects. The efficacy of virotherapy, however, was strongly limited by the host immune response in previous clinical trials. To enhance and prolong the antitumor activity of virotherapy, we combined the use of two newly developed tools: the genetically engineered measles virus (MV-NPL and the multilayer virus-coating method of layer-by-layer deposition of ionic polymers. We compared the oncolytic effects of this polymer-coated MV-NPL with the naked MV-NPL, both in vitro and in vivo. In the presence of anti-MV neutralizing antibodies, the polymer-coated virus showed more enhanced oncolytic activity than did the naked MV-NPL in vitro. We also examined antitumor activities in virus-treated mice. Complement-dependent cytotoxicity and antitumor activities were higher in mice treated with polymer-coated MV-NPL than in mice treated with the naked virus. This novel, polymer-coated MV-NPL is promising for clinical cancer therapy in the future.

  8. Anti-tumor effect of a recombinant plasmid expressing human interleukin-12: an initial research

    International Nuclear Information System (INIS)

    Zheng Chuansheng; Xia Xiangwen; Feng Gansheng; Li Xin; Liang Huimin; Liang Bin

    2010-01-01

    Objective: To study the anti-tumor effect of a recombinant plasmid expressing human interleukin-12 (pEGFP-CI I L- 12) in vivo and in vitro. Methods: We transduct the recombinant gene (pEGFP-CI I L-12) to liver cancer cell HepG 2 in vitro, and detect reproductive activity of the cell using MTT and the activity of expressing vascular endothelial growth factor(VEGF) using semiquantitative PCR. And then, we deliver the gene to rabbit liver tumor tissue intraarterial and combine with chemoembolization to observe the anti- tumor effect to VX 2 tumor in vivo. Results: There are no statistical difference compared With control group in activity of reproductive and expressing VEGF in vitro. In vivo, tumor growth rate significantly reduce in gene therapy combined with chemoembolization group. Conclusion: Recombinant gene (pEGFP-Cl I L-12) exhibit significant anti-tumor effect in vivo but not in vitro, perhaps the anti-tumor effect is associated with an indirect pathway instead of a direct pathway. (authors)

  9. Homologous recombination deficiency and host anti-tumor immunity in triple-negative breast cancer.

    Science.gov (United States)

    Telli, M L; Stover, D G; Loi, S; Aparicio, S; Carey, L A; Domchek, S M; Newman, L; Sledge, G W; Winer, E P

    2018-05-07

    Triple-negative breast cancer (TNBC) is associated with worse outcomes relative to other breast cancer subtypes. Chemotherapy remains the standard-of-care systemic therapy for patients with localized or metastatic disease, with few biomarkers to guide benefit. We will discuss recent advances in our understanding of two key biological processes in TNBC, homologous recombination (HR) DNA repair deficiency and host anti-tumor immunity, and their intersection. Recent advances in our understanding of homologous recombination (HR) deficiency, including FDA approval of PARP inhibitor olaparib for BRCA1 or BRCA2 mutation carriers, and host anti-tumor immunity in TNBC offer potential for new and biomarker-driven approaches to treat TNBC. Assays interrogating HR DNA repair capacity may guide treatment with agents inducing or targeting DNA damage repair. Tumor infiltrating lymphocytes (TILs) are associated with improved prognosis in TNBC and recent efforts to characterize infiltrating immune cell subsets and activate host anti-tumor immunity offer promise, yet challenges remain particularly in tumors lacking pre-existing immune infiltrates. Advances in these fields provide potential biomarkers to stratify patients with TNBC and guide therapy: induction of DNA damage in HR-deficient tumors and activation of existing or recruitment of host anti-tumor immune cells. Importantly, these advances provide an opportunity to guide use of existing therapies and development of novel therapies for TNBC. Efforts to combine therapies that exploit HR deficiency to enhance the activity of immune-directed therapies offer promise. HR deficiency remains an important biomarker target and potentially effective adjunct to enhance immunogenicity of 'immune cold' TNBCs.

  10. Structure and Antitumor and Immunomodulatory Activities of a Water-Soluble Polysaccharide from Dimocarpus longan Pulp

    Science.gov (United States)

    Meng, Fa-Yan; Ning, Yuan-Ling; Qi, Jia; He, Zhou; Jie, Jiang; Lin, Juan-Juan; Huang, Yan-Jun; Li, Fu-Sen; Li, Xue-Hua

    2014-01-01

    A new water-soluble polysaccharide (longan polysaccharide 1 (LP1)) was extracted and successfully purified from Dimocarpus longan pulp via diethylaminoethyl (DEAE)-cellulose anion-exchange and Sephacryl S-300 HR gel chromatography. The chemical structure was determined using Infrared (IR), gas chromatography (GC) and nuclear magnetic resonance (NMR) analysis. The results indicated that the molecular weight of the sample was 1.1 × 105 Da. Monosaccharide composition analysis revealed that LP1 was composed of Glc, GalA, Ara and Gal in a molar ratio of 5.39:1.04:0.74:0.21. Structural analysis indicated that LP1 consisted of a backbone of →4)-α-d-Glcp-(1→4)-α-d-GalpA-(1→4)-α-d-Glcp-(1→4)-β-d-Glcp-(1→ units with poly saccharide side chains composed of →2)-β-d-Fruf-(1→2)-l-sorbose-(1→ attached to the O-6 position of the α-d-Glcp residues. In vitro experiments indicated that LP1 had significantly high antitumor activity against SKOV3 and HO8910 tumor cells, with inhibition percentages of 40% and 50%, respectively. In addition, LP1 significantly stimulated the production of the cytokine interferon-γ (IFN-γ), increased the activity of murine macrophages and enhanced B- and T-lymphocyte proliferation. The results of this study demonstrate that LP1 has potential applications as a natural antitumor agent with immunomodulatory activity. PMID:24663085

  11. Discovery of DNA Topoisomerase I Inhibitors with Low-Cytotoxicity Based on Virtual Screening from Natural Products

    Directory of Open Access Journals (Sweden)

    Lan-Ting Xin

    2017-07-01

    Full Text Available Currently, DNA topoisomerase I (Topo I inhibitors constitute a family of antitumor agents with demonstrated clinical effects on human malignancies. However, the clinical uses of these agents have been greatly limited due to their severe toxic effects. Therefore, it is urgent to find and develop novel low toxic Topo I inhibitors. In recent years, during our ongoing research on natural antitumor products, a collection of low cytotoxic or non-cytotoxic compounds with various structures were identified from marine invertebrates, plants, and their symbiotic microorganisms. In the present study, new Topo I inhibitors were discovered from low cytotoxic and non-cytotoxic natural products by virtual screening with docking simulations in combination with bioassay test. In total, eight potent Topo I inhibitors were found from 138 low cytotoxic or non-cytotoxic compounds from coral-derived fungi and plants. All of these Topo I inhibitors demonstrated activities against Topo I-mediated relaxation of supercoiled DNA at the concentrations of 5–100 µM. Notably, the flavonoids showed higher Topo I inhibitory activities than other compounds. These newly discovered Topo I inhibitors exhibited structurally diverse and could be considered as a good starting point for the development of new antitumor lead compounds.

  12. A novel HDAC inhibitor, CG200745, inhibits pancreatic cancer cell growth and overcomes gemcitabine resistance

    OpenAIRE

    Lee, Hee Seung; Park, Soo Been; Kim, Sun A; Kwon, Sool Ki; Cha, Hyunju; Lee, Do Young; Ro, Seonggu; Cho, Joong Myung; Song, Si Young

    2017-01-01

    Pancreatic cancer is predominantly lethal, and is primarily treated using gemcitabine, with increasing resistance. Therefore, novel agents that increase tumor sensitivity to gemcitabine are needed. Histone deacetylase (HDAC) inhibitors are emerging therapeutic agents, since HDAC plays an important role in cancer initiation and progression. We evaluated the antitumor effect of a novel HDAC inhibitor, CG200745, combined with gemcitabine/erlotinib on pancreatic cancer cells and gemcitabine-resis...

  13. Induction of antitumor immunity through xenoplacental immunization

    Directory of Open Access Journals (Sweden)

    Agadjanyan Michael G

    2006-05-01

    Full Text Available Abstract Historically cancer vaccines have yielded suboptimal clinical results. We have developed a novel strategy for eliciting antitumor immunity based upon homology between neoplastic tissue and the developing placenta. Placenta formation shares several key processes with neoplasia, namely: angiogenesis, activation of matrix metalloproteases, and active suppression of immune function. Immune responses against xenoantigens are well known to break self-tolerance. Utilizing xenogeneic placental protein extracts as a vaccine, we have successfully induced anti-tumor immunity against B16 melanoma in C57/BL6 mice, whereas control xenogeneic extracts and B16 tumor extracts where ineffective, or actually promoted tumor growth, respectively. Furthermore, dendritic cells were able to prime tumor immunity when pulsed with the placental xenoantigens. While vaccination-induced tumor regression was abolished in mice depleted of CD4 T cells, both CD4 and CD8 cells were needed to adoptively transfer immunity to naïve mice. Supporting the role of CD8 cells in controlling tumor growth are findings that only freshly isolated CD8 cells from immunized mice were capable of inducing tumor cell caspases-3 activation ex vivo. These data suggest feasibility of using xenogeneic placental preparations as a multivalent vaccine potently targeting not just tumor antigens, but processes that are essential for tumor maintenance of malignant potential.

  14. A Review on Reinforcement of Natural Rubber by Silica Fillers for Use in Low-Rolling Resistance Tires

    NARCIS (Netherlands)

    Sarkawi, S.S.; Kaewsakul, Wisut; Sahakaro, Kannika; Dierkes, Wilma K.; Noordermeer, Jacobus W.M.

    2015-01-01

    High dispersion silica has recently become the preferred alternative to carbon black for low rolling resistance tyres. However, the combination of natural rubber with silica and a coupling agent remains a challenge, but also offers a tremendous potential for reduction of energy consumption of

  15. Correlation of Naturally Occurring HIV-1 Resistance to DEB025 with Capsid Amino Acid Polymorphisms

    Directory of Open Access Journals (Sweden)

    Brigitte Rosenwirth

    2013-03-01

    Full Text Available DEB025 (alisporivir is a synthetic cyclosporine with inhibitory activity against human immunodeficiency virus type-1 (HIV-1 and hepatitis C virus (HCV. It binds to cyclophilin A (CypA and blocks essential functions of CypA in the viral replication cycles of both viruses. DEB025 inhibits clinical HIV-1 isolates in vitro and decreases HIV-1 virus load in the majority of patients. HIV-1 isolates being naturally resistant to DEB025 have been detected in vitro and in nonresponder patients. By sequence analysis of their capsid protein (CA region, two amino acid polymorphisms that correlated with DEB025 resistance were identified: H87Q and I91N, both located in the CypA-binding loop of the CA protein of HIV-1. The H87Q change was by far more abundant than I91N. Additional polymorphisms in the CypA-binding loop (positions 86, 91 and 96, as well as in the N-terminal loop of CA were detected in resistant isolates and are assumed to contribute to the degree of resistance. These amino acid changes may modulate the conformation of the CypA-binding loop of CA in such a way that binding and/or isomerase function of CypA are no longer necessary for virus replication. The resistant HIV-1 isolates thus are CypA-independent.

  16. Identification of Ganoderma Disease Resistance Loci Using Natural Field Infection of an Oil Palm Multiparental Population

    Directory of Open Access Journals (Sweden)

    Sébastien Tisné

    2017-06-01

    Full Text Available Multi-parental populations are promising tools for identifying quantitative disease resistance loci. Stem rot caused by Ganoderma boninense is a major threat to palm oil production, with yield losses of up to 80% prompting premature replantation of palms. There is evidence of genetic resistance sources, but the genetic architecture of Ganoderma resistance has not yet been investigated. This study aimed to identify Ganoderma resistance loci using an oil palm multi-parental population derived from nine major founders of ongoing breeding programs. A total of 1200 palm trees of the multi-parental population was planted in plots naturally infected by Ganoderma, and their health status was assessed biannually over 25 yr. The data were treated as survival data, and modeled using the Cox regression model, including a spatial effect to take the spatial component in the spread of Ganoderma into account. Based on the genotypes of 757 palm trees out of the 1200 planted, and on pedigree information, resistance loci were identified using a random effect with identity-by-descent kinship matrices as covariance matrices in the Cox model. Four Ganoderma resistance loci were identified, two controlling the occurrence of the first Ganoderma symptoms, and two the death of palm trees, while favorable haplotypes were identified among a major gene pool for ongoing breeding programs. This study implemented an efficient and flexible QTL mapping approach, and generated unique valuable information for the selection of oil palm varieties resistant to Ganoderma disease.

  17. Identification of Ganoderma Disease Resistance Loci Using Natural Field Infection of an Oil Palm Multiparental Population

    Science.gov (United States)

    Tisné, Sébastien; Pomiès, Virginie; Riou, Virginie; Syahputra, Indra; Cochard, Benoît; Denis, Marie

    2017-01-01

    Multi-parental populations are promising tools for identifying quantitative disease resistance loci. Stem rot caused by Ganoderma boninense is a major threat to palm oil production, with yield losses of up to 80% prompting premature replantation of palms. There is evidence of genetic resistance sources, but the genetic architecture of Ganoderma resistance has not yet been investigated. This study aimed to identify Ganoderma resistance loci using an oil palm multi-parental population derived from nine major founders of ongoing breeding programs. A total of 1200 palm trees of the multi-parental population was planted in plots naturally infected by Ganoderma, and their health status was assessed biannually over 25 yr. The data were treated as survival data, and modeled using the Cox regression model, including a spatial effect to take the spatial component in the spread of Ganoderma into account. Based on the genotypes of 757 palm trees out of the 1200 planted, and on pedigree information, resistance loci were identified using a random effect with identity-by-descent kinship matrices as covariance matrices in the Cox model. Four Ganoderma resistance loci were identified, two controlling the occurrence of the first Ganoderma symptoms, and two the death of palm trees, while favorable haplotypes were identified among a major gene pool for ongoing breeding programs. This study implemented an efficient and flexible QTL mapping approach, and generated unique valuable information for the selection of oil palm varieties resistant to Ganoderma disease. PMID:28592650

  18. Boosting Natural Killer Cell-Based Immunotherapy with Anticancer Drugs: a Perspective.

    Science.gov (United States)

    Cifaldi, Loredana; Locatelli, Franco; Marasco, Emiliano; Moretta, Lorenzo; Pistoia, Vito

    2017-12-01

    Natural killer (NK) cells efficiently recognize and kill tumor cells through several mechanisms including the expression of ligands for NK cell-activating receptors on target cells. Different clinical trials indicate that NK cell-based immunotherapy represents a promising antitumor treatment. However, tumors develop immune-evasion strategies, including downregulation of ligands for NK cell-activating receptors, that can negatively affect antitumor activity of NK cells, which either reside endogenously, or are adoptively transferred. Thus, restoration of the expression of NK cell-activating ligands on tumor cells represents a strategic therapeutic goal. As discussed here, various anticancer drugs can fulfill this task via different mechanisms. We envision that the combination of selected chemotherapeutic agents with NK cell adoptive transfer may represent a novel strategy for cancer immunotherapy. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. The in vitro sustained release profile and antitumor effect of etoposide-layered double hydroxide nanohybrids

    Directory of Open Access Journals (Sweden)

    Qin LL

    2013-05-01

    Full Text Available Lili Qin,1 Mei Wang,2 Rongrong Zhu,3 Songhui You,1 Ping Zhou,1 Shilong Wang31Department of Physical Education, Tongji University, Shanghai, People's Republic of China; 2Department of Chemistry, Tongji University, Shanghai, People's Republic of China; 3School of Life Science and Technology, Tongji University, Shanghai, People's Republic of ChinaAbstract: Magnesium-aluminum layered double hydroxides intercalated with antitumor drug etoposide (VP16 were prepared for the first time using a two-step procedure. The X-ray powder diffraction data suggested the intercalation of VP16 into layers with the increased basal spacing from 0.84–1.18 nm was successful. Then, it was characterized by X-ray powder diffraction, Fourier transform infrared spectroscopy, thermogravimetry and differential thermal analysis, and transmission electron microscopy. The prepared nanoparticles, VP16-LDH, showed an average diameter of 62.5 nm with a zeta potential of 20.5 mV. Evaluation of the buffering effect of VP16-LDH indicated that the nanohybrids were ideal for administration of the drugs that treat human stomach irritation. The loading amount of intercalated VP16 was 21.94% and possessed a profile of sustained release. The mechanism of VP16-LDH release in the phosphate buffered saline solution at pH 7.4 is likely controlled by the diffusion of VP16 anions from inside to the surface of LDH particles. The in vitro cytotoxicity and antitumor assays indicated that VP16-LDH hybrids were less toxic to GES-1 cells while exhibiting better antitumor efficacy on MKN45 and SGC-7901 cells. These results imply that VP16-LDH is a potential antitumor drug for a broad range of gastric cancer therapeutic applications.Keywords: layered double hydroxides, etoposide, drug delivery, antitumor effect, sustained release

  20. Hydrogels based on polysaccharide-calcium phosphate with antibacterial / antitumor activity for 3D printing

    Science.gov (United States)

    Teterina, A. Yu; Fedotov, A. Yu; Zobkov, Yu V.; Sergeeva, N. S.; Sviridova, I. K.; Kirsanova, V. A.; Karalkin, P. A.; Komlev, V. S.

    2018-04-01

    The purpose of this study was to develop hydrogels for 3D printing of sodium alginate/gelatin/octacalcium phosphate-based constructs with antibacterial and antitumor activity intended for bone defects replacement in patients with malignant diseases. In this work, we evaluated the drug release kinetic and physico-chemical characteristics of constructs, as well as their specific activity, biocompatibility and osteoplastic properties by means of in vitro and in vivo tests. The principal possibility of creating the biocompatible bone substitutes with antibacterial/antitumor activity and osteoconductive-retaining properties of 3D printing method was demonstrated.

  1. Total synthesis and related studies of large, strained, and bioactive natural products

    Science.gov (United States)

    HIRAMA, Masahiro

    2016-01-01

    Our chemical syntheses and related scientific investigations of natural products with complex architectures and powerful biological activities are described, focusing on the very large 3 nm-long polycyclic ethers called the ciguatoxins, highly strained and labile chromoprotein antitumor antibiotics featuring nine-membered enediyne cores, and extremely potent anthelmintic macrolides called the avermectins. PMID:27725470

  2. Effector Regulatory T Cells Reflect the Equilibrium between Antitumor Immunity and Autoimmunity in Adult T-cell Leukemia.

    Science.gov (United States)

    Ureshino, Hiroshi; Shindo, Takero; Nishikawa, Hiroyoshi; Watanabe, Nobukazu; Watanabe, Eri; Satoh, Natsuko; Kitaura, Kazutaka; Kitamura, Hiroaki; Doi, Kazuko; Nagase, Kotaro; Kimura, Hiromi; Samukawa, Makoto; Kusunoki, Susumu; Miyahara, Masaharu; Shin-I, Tadasu; Suzuki, Ryuji; Sakaguchi, Shimon; Kimura, Shinya

    2016-08-01

    The regulatory T cells (Treg) with the most potent immunosuppressive activity are the effector Tregs (eTreg) with a CD45RA(-)Foxp3(++)CCR4(+) phenotype. Adult T-cell leukemia (ATL) cells often share the Treg phenotype and also express CCR4. Although mogamulizumab, a monoclonal antibody to CCR4, shows marked antitumor effects against ATL and peripheral T-cell lymphoma, concerns have been raised that it may induce severe autoimmune immunopathology by depleting eTregs. Here, we present case reports for two patients with ATL who responded to mogamulizumab but developed a severe skin rash and autoimmune brainstem encephalitis. Deep sequencing of the T-cell receptor revealed that ATL cells and naturally occurring Tregs within the cell population with a Treg phenotype can be clearly distinguished according to CADM1 expression. The onset of skin rash and brainstem encephalitis was coincident with eTreg depletion from the peripheral blood, whereas ATL relapses were coincident with eTreg recovery. These results imply that eTreg numbers in the peripheral blood sensitively reflect the equilibrium between antitumor immunity and autoimmunity, and that mogamulizumab might suppress ATL until the eTreg population recovers. Close monitoring of eTreg numbers is crucial if we are to provide immunomodulatory treatments that target malignancy without severe adverse events. Cancer Immunol Res; 4(8); 644-9. ©2016 AACR. ©2016 American Association for Cancer Research.

  3. Esters of pyrazinoic acid are active against pyrazinamide-resistant strains of Mycobacterium tuberculosis and other naturally resistant mycobacteria in vitro and ex vivo within macrophages.

    KAUST Repository

    Pires, David; Valente, Emí lia; Simoes, Marta; Carmo, Nuno; Testa, Bernard; Constantino, Luí s; Anes, Elsa

    2015-01-01

    In previous work, we have shown that POA esters and amides synthesized in our laboratory were stable in plasma. Although the amides did not present significant activity, the esters were active against sensitive mycobacteria at concentrations 5-to-10 fold lower than those of PZA. Here, we report that these POA derivatives possess antibacterial efficacy in vitro and ex vivo against several species and strains of Mycobacterium with natural or acquired resistance to PZA, including M. bovis and M. avium. Our results indicate that the resistance was probably overcome by cleavage of the prodrugs into POA and a long-chain alcohol. Although it is not possible to rule out that the esters may have intrinsic activity per se, we bring evidence here that long-chain fatty alcohols possess a significant anti-mycobacterial effect against PZA-resistant species and strains and are not mere inactive promoieties. These findings may lead to candidate dual-drugs having enhanced activity against both PZA-susceptible and PZA-resistant isolates and being suitable for clinical development.

  4. Doxil Synergizes with Cancer Immunotherapies to Enhance Antitumor Responses in Syngeneic Mouse Models

    Directory of Open Access Journals (Sweden)

    Jonathan Rios-Doria

    2015-08-01

    Full Text Available Based on the previously described roles of doxorubicin in immunogenic cell death, both doxorubicin and liposomal doxorubicin (Doxil were evaluated for their ability to boost the antitumor response of different cancer immunotherapies including checkpoint blockers (anti–PD-L1, PD-1, and CTLA-4 mAbs and TNF receptor agonists (OX40 and GITR ligand fusion proteins in syngeneic mouse models. In a preventative CT26 mouse tumor model, both doxorubicin and Doxil synergized with anti–PD-1 and CTLA-4 mAbs. Doxil was active when CT26 tumors were grown in immunocompetent mice but not immunocompromised mice, demonstrating that Doxil activity is increased in the presence of a functional immune system. Using established tumors and maximally efficacious doses of Doxil and cancer immunotherapies in either CT26 or MCA205 tumor models, combination groups produced strong synergistic antitumor effects, a larger percentage of complete responders, and increased survival. In vivo pharmacodynamic studies showed that Doxil treatment decreased the percentage of tumor-infiltrating regulatory T cells and, in combination with anti–PD-L1, increased the percentage of tumor-infiltrating CD8+ T cells. In the tumor, Doxil administration increased CD80 expression on mature dendritic cells. CD80 expression was also increased on both monocytic and granulocytic myeloid cells, suggesting that Doxil may induce these tumor-infiltrating cells to elicit a costimulatory phenotype capable of activating an antitumor T-cell response. These results uncover a novel role for Doxil in immunomodulation and support the use of Doxil in combination with checkpoint blockade or TNFR agonists to increase response rates and antitumor activity.

  5. Identification of methicillin-resistant Staphylococcus aureus within the Nation’s Veterans Affairs Medical Centers using natural language processing

    Directory of Open Access Journals (Sweden)

    Jones Makoto

    2012-07-01

    Full Text Available Abstract Background Accurate information is needed to direct healthcare systems’ efforts to control methicillin-resistant Staphylococcus aureus (MRSA. Assembling complete and correct microbiology data is vital to understanding and addressing the multiple drug-resistant organisms in our hospitals. Methods Herein, we describe a system that securely gathers microbiology data from the Department of Veterans Affairs (VA network of databases. Using natural language processing methods, we applied an information extraction process to extract organisms and susceptibilities from the free-text data. We then validated the extraction against independently derived electronic data and expert annotation. Results We estimate that the collected microbiology data are 98.5% complete and that methicillin-resistant Staphylococcus aureus was extracted accurately 99.7% of the time. Conclusions Applying natural language processing methods to microbiology records appears to be a promising way to extract accurate and useful nosocomial pathogen surveillance data. Both scientific inquiry and the data’s reliability will be dependent on the surveillance system’s capability to compare from multiple sources and circumvent systematic error. The dataset constructed and methods used for this investigation could contribute to a comprehensive infectious disease surveillance system or other pressing needs.

  6. In vitro antioxidant, antibacterial and anti-tumor activities of total ...

    African Journals Online (AJOL)

    Purpose: To investigate the in vitro antioxidant, antibacterial and anti-tumor activities of total flavonoids from Elsholtzia densa Benth of Sichuan Province, China. Methods: The total flavonoids of Elsholtzia densa Bent were extracted utilizing the ultrasonic extraction method, and purified by D101 macroporous adsorption resin ...

  7. Fallopia japonica, a Natural Modulator, Can Overcome Multidrug Resistance in Cancer Cells

    Directory of Open Access Journals (Sweden)

    Safaa Yehia Eid

    2015-01-01

    Full Text Available Resistance of cancer cells to chemotherapy is controlled by the decrease of intracellular drug accumulation, increase of detoxification, and diminished propensity of cancer cells to undergo apoptosis. ATP-binding cassette (ABC membrane transporters with intracellular metabolic enzymes contribute to the complex and unresolved phenomenon of multidrug resistance (MDR. Natural products as alternative medicine have great potential to discover new MDR inhibitors with diverse modes of action. In this study, we characterized several extracts of traditional Chinese medicine (TCM plants (N = 16 for their interaction with ABC transporters, cytochrome P3A4 (CYP3A4, and glutathione-S-transferase (GST activities and their cytotoxic effect on different cancer cell lines. Fallopia japonica (FJ (Polygonaceae shows potent inhibitory effect on CYP3A4 P-glycoprotein activity about 1.8-fold when compared to verapamil as positive control. FJ shows significant inhibitory effect (39.81% compared with the known inhibitor ketoconazole and 100 μg/mL inhibited GST activity to 14 μmol/min/mL. FJ shows moderate cytotoxicity in human Caco-2, HepG-2, and HeLa cell lines; IC50 values were 630.98, 198.80, and 317.37 µg/mL, respectively. LC-ESI-MS were used to identify and quantify the most abundant compounds, emodin, polydatin, and resveratrol, in the most active extract of FJ. Here, we present the prospect of using Fallopia japonica as natural products to modulate the function of ABC drug transporters. We are conducting future study to evaluate the ability of the major active secondary metabolites of Fallopia japonica to modulate MDR and their impact in case of failure of chemotherapy.

  8. Vγ9Vδ2 T cells and zoledronate mediate antitumor activity in an orthotopic mouse model of human chondrosarcoma.

    Science.gov (United States)

    Sun, L; Li, Y; Jiang, Z; Zhang, J; Li, H; Li, B; Ye, Z

    2016-06-01

    Chondrosarcoma (CS) is a cartilaginous malignant neoplasm characterized by resistance to conventional adjuvant therapy. The prognosis of unresectable or metastatic CS is poor. Therefore, it is imperative to explore novel therapeutic approaches to improve the treatment efficacy for those CS patients. Emerging data has implicated the synergistic antitumor activity of zoledronate (ZOL) and Vγ9Vδ2 T cells. However, whether ZOL-stimulated Vγ9Vδ2 T cells could infiltrate bone sarcoma and inhibit tumor growth has not been thoroughly answered yet. In this study, Vγ9Vδ2 T cells from healthy donors and CS patients were expanded in the presence of ZOL (1 μM) and IL-2 (400 IU/ml). The antitumor activity of Vγ9Vδ2 T cells to ZOL-pretreated human CS was examined both in vitro and in vivo. ZOL pretreatment substantially enhanced the cytotoxicity of Vγ9Vδ2 T cells to SW1353 and primary CS cells. ZOL potentiated the migration and cytotoxicity of Vγ9Vδ2 T cells to SW1353 in dose- and time-dependent manner. Moreover, weekly intravenous ZOL followed by Vγ9Vδ2 T cells inhibited subcutaneous xenograft growth. Thus, Vγ9Vδ2 T cells were able to infiltrate bone tumor and significantly suppressed the development of orthotopic SW1353 xenografts. Altogether, the study raises the possibility of combining ZOL with Vγ9Vδ2 T cells for CS treatment.

  9. Structure and function of ABCG2-rich extracellular vesicles mediating multidrug resistance.

    Directory of Open Access Journals (Sweden)

    Vicky Goler-Baron

    2011-01-01

    Full Text Available Multidrug resistance (MDR is a major impediment to curative cancer chemotherapy. The ATP-Binding Cassette transporters ABCG2, ABCB1 and ABCC2 form a unique defense network against multiple structurally and functionally distinct chemotherapeutics, thereby resulting in MDR. Thus, deciphering novel mechanisms of MDR and their overcoming is a major goal of cancer research. Recently we have shown that overexpression of ABCG2 in the membrane of novel extracellular vesicles (EVs in breast cancer cells results in mitoxantrone resistance due to its dramatic sequestration in EVs. However, nothing is known about EVs structure, biogenesis and their ability to concentrate multiple antitumor agents. To this end, we here found that EVs are structural and functional homologues of bile canaliculi, are apically localized, sealed structures reinforced by an actin-based cytoskeleton and secluded from the extracellular milieu by the tight junction proteins occludin and ZO-1. Apart from ABCG2, ABCB1 and ABCC2 were also selectively targeted to the membrane of EVs. Moreover, Ezrin-Radixin-Moesin protein complex selectively localized to the border of the EVs membrane, suggesting a key role for the tethering of MDR pumps to the actin cytoskeleton. The ability of EVs to concentrate and sequester different antitumor drugs was also explored. Taking advantage of the endogenous fluorescence of anticancer drugs, we found that EVs-forming breast cancer cells display high level resistance to topotecan, imidazoacridinones and methotrexate via efficient intravesicular drug concentration hence sequestering them away from their cellular targets. Thus, we identified a new modality of anticancer drug compartmentalization and resistance in which multiple chemotherapeutics are actively pumped from the cytoplasm and highly concentrated within the lumen of EVs via a network of MDR transporters differentially targeted to the EVs membrane. We propose a composite model for the structure and

  10. Anti-tumor bioactivities of curcumin on mice loaded with gastric carcinoma.

    Science.gov (United States)

    Wang, Xiao-Ping; Wang, Qiao-Xia; Lin, Huan-Ping; Chang, Na

    2017-09-20

    Curcumin, a derivative from the dried rhizome of curcuma longa, has been proven to possess anti-tumor effects. However, the detailed molecular mechanisms have not been fully elucidated. In this study, we aimed to explore the anti-tumor mechanisms of curcumin in treating gastric cancer. BALB/C mice grafted with a mouse gastric adenocarcinoma cell line (MFC) were used as the experimental model. Mice received different doses of curcumin after grafting. Tumor size was measured and tumor weight was determined after tumor inoculation. TUNEL assay and flow cytometric analysis were applied to evaluate the apoptosis of the cancer cells. Serum cytokines IFN-γ, TNF-α, granzyme B and perforin were detected by ELISA assay. The anti-tumor effect was determined using cytotoxic T-lymphocyte (CTL) assays and in vivo tumor prevention tests. The expression of DEC1, HIF-1α, STAT3 and VEGF in tumor tissues was examined by immunostaining and analyzed using an Image J analysis system. Compared with controls, tumor growth (size and weight) was significantly inhibited by curcumin treatment (P curcumin treatment group. Splenocyte cells from mice treated with curcumin exhibited higher cytolytic effects on MFC cancer cells than those from mice treated with saline (P curcumin treatment. Our results indicate that curcumin inhibits the proliferation of gastric carcinoma by inducing the apoptosis of tumor cells, activating immune cells to secrete a large amount of cytokines, and down-regulating the DEC1, HIF-1α, VEGF and STAT3 signal transduction pathways.

  11. Cellular immunotherapy using irradiated lung cancer cell vaccine co-expressing GM-CSF and IL-18 can induce significant antitumor effects

    International Nuclear Information System (INIS)

    Tian, Hongwei; Zhang, Xiaomei; Dai, Lei; Chen, Xiaolei; Zhang, Shuang; Yang, Yang; Yu, Dechao; Wei, Yuquan; Deng, Hongxin; Shi, Gang; Yang, Guoyou; Zhang, Junfeng; Li, Yiming; Du, Tao; Wang, Jianzhou; Xu, Fen; Cheng, Lin

    2014-01-01

    Although the whole tumor cell vaccine can provide the best source of immunizing antigens, there is still a limitation that most tumors are not naturally immunogenic. Tumor cells genetically modified to secrete immune activating cytokines have been proved to be more immunogenic. IL-18 could augment proliferation of T cells and cytotoxicity of NK cells. GM-CSF could stimulate dendritic cells, macrophages and enhance presentation of tumor antigens. In our study, we used mouse GM-CSF combined with IL-18 to modify Lewis lung cancer LL/2, then investigated whether vaccination could suppress tumor growth and promote survival. The Lewis lung cancer LL/2 was transfected with co-expressing mouse GM-CSF and IL-18 plasmid by cationic liposome, then irradiated with a sublethal dose X ray (100 Gy) to prepare vaccines. Mice were subcutaneously immunized with this inactivated vaccine and then inoculated with autologous LL/2 to estimate the antitumor efficacy. The studies reported here showed that LL/2 tumor cell vaccine modified by a co-expressing mouse GM-CSF and IL-18 plasmid could significantly inhibit tumor growth and increased survival of the mice bearing LL/2 tumor whether prophylactic or adoptive immunotherapy in vivo. A significant reduction of proliferation and increase of apoptosis were also observed in the tumor treated with vaccine of co-expressing GM-CSF and IL-18. The potent antitumor effect correlated with higher secretion levels of pro-inflammatory cytokines such as IL-18, GM-CSF, interferon-γ in serum, the proliferation of CD4 + IFN-γ + , CD8 + IFN-γ + T lymphocytes in spleen and the infiltration of CD4 + , CD8 + T in tumor. Furthermore, the mechanism of tumor-specific immune response was further proved by 51 Cr cytotoxicity assay in vitro and depletion of CD4, CD8, NK immune cell subsets in vivo. The results suggested that the antitumor mechanism was mainly depended on CD4 + , CD8 + T lymphocytes. These results provide a new insight into therapeutic mechanisms

  12. Augmentation of Antitumor Immunity by Human and Mouse CAR T Cells Secreting IL-18

    Directory of Open Access Journals (Sweden)

    Biliang Hu

    2017-09-01

    Full Text Available The effects of transgenically encoded human and mouse IL-18 on T cell proliferation and its application in boosting chimeric antigen receptor (CAR T cells are presented. Robust enhancement of proliferation of IL-18-secreting human T cells occurred in a xenograft model, and this was dependent on TCR and IL-18R signaling. IL-18 augmented IFN-γ secretion and proliferation of T cells activated by the endogenous TCR. TCR-deficient, human IL-18-expressing CD19 CAR T cells exhibited enhanced proliferation and antitumor activity in the xenograft model. Antigen-propelled activation of cytokine helper ensemble (APACHE CAR T cells displayed inducible expression of IL-18 and enhanced antitumor immunity. In an intact mouse tumor model, CD19-IL-18 CAR T cells induced deeper B cell aplasia, significantly enhanced CAR T cell proliferation, and effectively augmented antitumor effects in mice with B16F10 melanoma. These findings point to a strategy to develop universal CAR T cells for patients with solid tumors.

  13. Synergistic and complete reversal of the multidrug resistance of mitoxantrone hydrochloride by three-in-one multifunctional lipid-sodium glycocholate nanocarriers based on simultaneous BCRP and Bcl-2 inhibition.

    Science.gov (United States)

    Ling, Guixia; Zhang, Tianhong; Zhang, Peng; Sun, Jin; He, Zhonggui

    Multidrug resistance (MDR) is a severe obstacle to successful chemotherapy due to its complicated nature that involves multiple mechanisms, such as drug efflux by transporters (P-glycoprotein and breast cancer resistance protein, BCRP) and anti-apoptotic defense (B-cell lymphoma, Bcl-2). To synergistically and completely reverse MDR by simultaneous inhibition of pump and non-pump cellular resistance, three-in-one multifunctional lipid-sodium glycocholate (GcNa) nanocarriers (TMLGNs) have been designed for controlled co-delivery of water-soluble cationic mitoxantrone hydrochloride (MTO), cyclosporine A (CsA - BCRP inhibitor), and GcNa (Bcl-2 inhibitor). GcNa and dextran sulfate were incorporated as anionic compounds to enhance the encapsulation efficiency of MTO (up to 97.8%±1.9%) and sustain the release of cationic MTO by electrostatic interaction. The results of a series of in vitro and in vivo investigations indicated that the TMLGNs were taken up by the resistant cancer cells by an endocytosis pathway that escaped the efflux induced by BCRP, and the simultaneous release of CsA with MTO further efficiently inhibited the efflux of the released MTO by BCRP; meanwhile GcNa induced the apoptosis process, and an associated synergistic antitumor activity and reversion of MDR were achieved because the reversal index was almost 1.0.

  14. Chimeric Antigen Receptor-Engineered NK-92 Cells: An Off-the-Shelf Cellular Therapeutic for Targeted Elimination of Cancer Cells and Induction of Protective Antitumor Immunity

    Directory of Open Access Journals (Sweden)

    Congcong Zhang

    2017-05-01

    Full Text Available Significant progress has been made in recent years toward realizing the potential of natural killer (NK cells for cancer immunotherapy. NK cells can respond rapidly to transformed and stressed cells and have the intrinsic potential to extravasate and reach their targets in almost all body tissues. In addition to donor-derived primary NK cells, also the established NK cell line NK-92 is being developed for adoptive immunotherapy, and general safety of infusion of irradiated NK-92 cells has been established in phase I clinical trials with clinical responses observed in some of the cancer patients treated. To enhance their therapeutic utility, NK-92 cells have been modified to express chimeric antigen receptors (CARs composed of a tumor-specific single chain fragment variable antibody fragment fused via hinge and transmembrane regions to intracellular signaling moieties such as CD3ζ or composite signaling domains containing a costimulatory protein together with CD3ζ. CAR-mediated activation of NK cells then bypasses inhibitory signals and overcomes NK resistance of tumor cells. In contrast to primary NK cells, CAR-engineered NK-92 cell lines suitable for clinical development can be established from molecularly and functionally well-characterized single cell clones following good manufacturing practice-compliant procedures. In preclinical in vitro and in vivo models, potent antitumor activity of NK-92 variants targeted to differentiation antigens expressed by hematologic malignancies, and overexpressed or mutated self-antigens associated with solid tumors has been found, encouraging further development of CAR-engineered NK-92 cells. Importantly, in syngeneic mouse tumor models, induction of endogenous antitumor immunity after treatment with CAR-expressing NK-92 cells has been demonstrated, resulting in cures and long-lasting immunological memory protecting against tumor rechallenge at distant sites. Here, we summarize the current status and future

  15. Antitumor and biological effects of black pine (Pinus nigra) pollen nuclease

    Czech Academy of Sciences Publication Activity Database

    Lipovová, P.; Podzimek, T.; Orctová, Lidmila; Matoušek, Jaroslav; Poučková, P.; Souček, J.; Matoušek, Josef

    2008-01-01

    Roč. 55, - (2008), s. 158-164 ISSN 0028-2685 Institutional research plan: CEZ:AV0Z50510513; CEZ:AV0Z50450515 Keywords : pollen nuclease * Antitumor effect Subject RIV: FD - Oncology ; Hematology Impact factor: 1.179, year: 2008

  16. Pristimerin overcomes adriamycin resistance in breast cancer cells through suppressing Akt signaling

    Science.gov (United States)

    XIE, GUI'E; YU, XINPEI; LIANG, HUICHAO; CHEN, JINGSONG; TANG, XUEWEI; WU, SHAOQING; LIAO, CAN

    2016-01-01

    Breast cancer remains a major public health problem worldwide. Chemotherapy serves an important role in the treatment of breast cancer. However, resistance to chemotherapeutic agents, in particular, multi-drug resistance (MDR), is a major cause of treatment failure in cancer. Agents that can either enhance the effects of chemotherapeutics or overcome chemoresistance are urgently needed for the treatment of breast cancer. Pristimerin, a quinonemethide triterpenoid compound isolated from Celastraceae and Hippocrateaceae, has been shown to possess antitumor, anti-inflammatory, antioxidant and insecticidal properties. The aim of the present study was to investigate whether pristimerin can override chemoresistance in MCF-7/adriamycin (ADR)-resistant human breast cancer cells. The results demonstrated that pristimerin indeed displayed potent cytocidal effect on multidrug-resistant MCF-7/ADR breast cancer cells, and that these effects occurred through the suppression of Akt signaling, which in turn led to the downregulation of antiapoptotic effectors and increased apoptosis. These findings indicate that use of pristimerin may represent a potentially promising approach for the treatment of ADR-resistant breast cancer. PMID:27123073

  17. Identification of Ganoderma Disease Resistance Loci Using Natural Field Infection of an Oil Palm Multiparental Population.

    Science.gov (United States)

    Tisné, Sébastien; Pomiès, Virginie; Riou, Virginie; Syahputra, Indra; Cochard, Benoît; Denis, Marie

    2017-06-07

    Multi-parental populations are promising tools for identifying quantitative disease resistance loci. Stem rot caused by Ganoderma boninense is a major threat to palm oil production, with yield losses of up to 80% prompting premature replantation of palms. There is evidence of genetic resistance sources, but the genetic architecture of Ganoderma resistance has not yet been investigated. This study aimed to identify Ganoderma resistance loci using an oil palm multi-parental population derived from nine major founders of ongoing breeding programs. A total of 1200 palm trees of the multi-parental population was planted in plots naturally infected by Ganoderma , and their health status was assessed biannually over 25 yr. The data were treated as survival data, and modeled using the Cox regression model, including a spatial effect to take the spatial component in the spread of Ganoderma into account. Based on the genotypes of 757 palm trees out of the 1200 planted, and on pedigree information, resistance loci were identified using a random effect with identity-by-descent kinship matrices as covariance matrices in the Cox model. Four Ganoderma resistance loci were identified, two controlling the occurrence of the first Ganoderma symptoms, and two the death of palm trees, while favorable haplotypes were identified among a major gene pool for ongoing breeding programs. This study implemented an efficient and flexible QTL mapping approach, and generated unique valuable information for the selection of oil palm varieties resistant to Ganoderma disease. Copyright © 2017 Tisné et al.

  18. Targeting Hodgkin and Reed–Sternberg Cells with an Inhibitor of Heat-Shock Protein 90: Molecular Pathways of Response and Potential Mechanisms of Resistance

    Directory of Open Access Journals (Sweden)

    Priscilla Segges

    2018-03-01

    Full Text Available Classical Hodgkin lymphoma (cHL cells overexpress heat-shock protein 90 (HSP90, an important intracellular signaling hub regulating cell survival, which is emerging as a promising therapeutic target. Here, we report the antitumor effect of celastrol, an anti-inflammatory compound and a recognized HSP90 inhibitor, in Hodgkin and Reed–Sternberg cell lines. Two disparate responses were recorded. In KM-H2 cells, celastrol inhibited cell proliferation, induced G0/G1 arrest, and triggered apoptosis through the activation of caspase-3/7. Conversely, L428 cells exhibited resistance to the compound. A proteomic screening identified a total of 262 differentially expressed proteins in sensitive KM-H2 cells and revealed that celastrol’s toxicity involved the suppression of the MAPK/ERK (extracellular signal regulated kinase/mitogen activated protein kinase pathway. The apoptotic effects were preceded by a decrease in RAS (proto-oncogene protein Ras, p-ERK1/2 (phospho-extracellular signal-regulated Kinase-1/2, and c-Fos (proto-oncogene protein c-Fos protein levels, as validated by immunoblot analysis. The L428 resistant cells exhibited a marked induction of HSP27 mRNA and protein after celastrol treatment. Our results provide the first evidence that celastrol has antitumor effects in cHL cells through the suppression of the MAPK/ERK pathway. Resistance to celastrol has rarely been described, and our results suggest that in cHL it may be mediated by the upregulation of HSP27. The antitumor properties of celastrol against cHL and whether the disparate responses observed in vitro have clinical correlates deserve further research.

  19. Navigating into the binding pockets of the HER family protein kinases: discovery of novel EGFR inhibitor as antitumor agent.

    Science.gov (United States)

    Liu, Wei; Ning, Jin-Feng; Meng, Qing-Wei; Hu, Jing; Zhao, Yan-Bin; Liu, Chao; Cai, Li

    2015-01-01

    The epidermal growth factor receptor (EGFR) family has been validated as a successful antitumor drug target for decades. Known EGFR inhibitors were exposed to distinct drug resistance against the various EGFR mutants within non-small-cell lung cancer (NSCLC), particularly the T790M mutation. Although so far a number of studies have been reported on the development of third-generation EGFR inhibitors for overcoming the resistance issue, the design procedure largely depends on the intuition of medicinal chemists. Here we retrospectively make a detailed analysis of the 42 EGFR family protein crystal complexes deposited in the Protein Data Bank (PDB). Based on the analysis of inhibitor binding modes in the kinase catalytic cleft, we identified a potent EGFR inhibitor (compound A-10) against drug-resistant EGFR through fragment-based drug design. This compound showed at least 30-fold more potency against EGFR T790M than the two control molecules erlotinib and gefitinib in vitro. Moreover, it could exhibit potent HER2 inhibitory activities as well as tumor growth inhibitory activity. Molecular docking studies revealed a structural basis for the increased potency and mutant selectivity of this compound. Compound A-10 may be selected as a promising candidate in further preclinical studies. In addition, our findings could provide a powerful strategy to identify novel selective kinase inhibitors on the basis of detailed kinase-ligand interaction space in the PDB.

  20. Anti-tumor response with immunologically modified carbon nanotubes and phototherapy

    Science.gov (United States)

    Acquaviva, Joseph T.; Zhou, Feifan; Boarman, Ellen; Chen, Wei R.

    2013-02-01

    While successes of different cancer therapies have been achieved in various degrees a systemic immune response is needed to effectively treat late-stage, metastatic cancers, and to establish long-term tumor resistance in the patients. A novel method for combating metastatic cancers has been developed using immunologically modified carbon nanotubes in conjunction with phototherapy. Glycated chitosan (GC) is a potent immunological adjuvant capable of increasing host immune responses, including antigen presentation by activation of dendritic cells (DCs) and causing T cell proliferation. GC is also an effective surfactant for nanomaterials. By combining single-walled carbon nanotubes (SWNTs) and GC, immunologically modified carbon nanotubes (SWNT-GC) were constructed. The SWNT-GC suspension retains the enhanced light absorption properties in the near infrared (NIR) region and the ability to enter cells, which are characteristic of SWNTs. The SWNT-GC also retains the immunological properties of GC. Cellular SWNT-GC treatments increased macrophage activity, DC activation and T cell proliferation. When cellular SWNT-GC was irradiated with a laser of an appropriate wavelength, these immune activities could be enhanced. The combination of laser irradiation and SWNT-GC induced cellular toxicity in targeted tumor cells, leading to a systemic antitumor response. Immunologically modified carbon nanotubes in conjunction with phototherapy is a novel and promising method to produce a systemic immune response for the treatment of metastatic cancers.

  1. OFFICIAL MEDICATIONS FOR ANTI-TUMOR GENE THERAPY

    Directory of Open Access Journals (Sweden)

    E. R. Nemtsova

    2016-01-01

    Full Text Available This is a review of modern literature data of official medications for anti-tumor gene therapy as well as of medications that finished clinical trials.The article discusses the concept of gene therapy, the statistical analysis results of initiated clinical trials of gene products, the most actively developing directions of anticancer gene therapy, and the characteristics of anti-tumor gene medications.Various delivery systems for gene material are being examined, including viruses that are defective in  replication (Gendicine™ and Advexin and oncolytic (tumor specific conditionally replicating viruses (Oncorine™, ONYX-015, Imlygic®.By now three preparations for intra-tumor injection have been introduced into oncology clinical practice: two of them – Gendicine™ and Oncorine™ have been registered in China, and one of them – Imlygic® has been registered in the USA. Gendicine™ and Oncorine™ are based on the wild type p53 gene and are designed for treatment of patients with head and neck malignancies. Replicating adenovirus is the delivery system in Gendicine™, whereas oncolytic adenovirus is the vector for gene material in Oncorine™. Imlygic® is based on the  recombinant replicating HSV1 virus with an introduced GM–CSF gene and is designed for treatment of  melanoma patients. These medications are well tolerated and do not cause any serious adverse events. Gendicine™ and Oncorine™ are not effective in monotherapy but demonstrate pronounced synergism with chemoand radiation therapy. Imlygic® has just started the post marketing trials.

  2. Characterization and anti-tumor effects of chondroitin sulfate-chitosan nanoparticles delivery system

    Science.gov (United States)

    Hu, Chieh-Shen; Tang, Sung-Ling; Chiang, Chiao-Hsi; Hosseinkhani, Hossein; Hong, Po-Da; Yeh, Ming-Kung

    2014-11-01

    We prepared chondroitin sulfate (ChS)-chitosan (CS) nanoparticles (NPs) as a delivery carrier, and doxorubicin (Dox) was used as a model drug. The physicochemical properties and biological activities of the Dox-ChS-CS NPs including the release profile, cell cytotoxicity, cellular internalization, and in vivo anti-tumor effects were evaluated. The ChS-CS NPs and Dox-ChS-CS NPs had a mean size of 262.0 ± 15.0 and 369.4 ± 77.4 nm, and a zeta potential of 30.2 ± 0.9 and 20.6 ± 3.1 mV, respectively. In vitro release tests showed that the 50 % release time for the Dox-ChS-CS NPs was 20 h. Two hepatoma cell models, HepG2 and HuH6, were used for evaluating the cytotoxicity and cell uptake efficiency of the Dox-ChS-CS NPs. A significant difference was observed between doxorubicin solution and the Dox-ChS-CS NPs in the cellular uptake within 60 min ( p < 0.01). For the in vivo human xenograft-nude mouse model, the Dox-ChS-CS NPs were more effective with less body weight loss and anti-tumor growth suppression in comparison with the Dox solution. The prepared Dox-ChS-CS NPs offer a new effective targeting nanoparticle delivery system platform for anti-tumor therapy.

  3. Genetic diversity/impurity estimation in sources of natural resistance against cotton leaf curl disease in pakistan

    International Nuclear Information System (INIS)

    Sarwar, G.

    2007-01-01

    Cotton accounts for more than 60% of Pakistan's export earnings through the export of both raw cotton and cotton products. An epidemic of cotton leaf curl disease (CLCuD) in Pakistan during the 1990s led to the withdrawal of high yielding cotton cultivars. Due of their susceptibility to the disease. The identification of natural resistance in some genotypes provided a means to manage reduce losses due to the disease. But it has been an adversity that almost all these resistant varieties have ultimately 'lost' their resistance. There are also reports that the original sources of resistance, as well as the varieties developed from them, are now susceptible to the disease when grafted with infected scion. For the present studies. Seed of two resistant varieties (LRA-5166 and (CP-152) was obtained from six different research organizations. Plants raised from these seed were grafted with symptomatic scion and used for morphological comparisons. Our results indicated that the genetic pool of these cultivars is not well maintained and that an unacceptable diversity impurity is present within and among the genetic stock of both these lines. There is thus a requirement for screening of these elite lines at the molecular level to ensure the purity of these varieties for future development. The virus causing CLCuD showed change by recombination making the search for new sources of resistance, as well as the maintenance of established sources, indispensable for the sustainable cotton production in Pakistan. (author)

  4. Anti-tumor activity of tetrodotoxin extracted from the Masked Puffer ...

    African Journals Online (AJOL)

    Anti-tumor activity of tetrodotoxins extracted from the skin of the Masked Puffer fish (Arothron diadematus) from the Red Sea was evaluated using the Ehrlich ascite carcinoma tumor model in mice. Activity was assessed using a variety of cellular and liver biochemical parameters. Experimental mice were divided into 4 equal ...

  5. Reversing resistance to vascular-disrupting agents by blocking late mobilization of circulating endothelial progenitor cells.

    Science.gov (United States)

    Taylor, Melissa; Billiot, Fanny; Marty, Virginie; Rouffiac, Valérie; Cohen, Patrick; Tournay, Elodie; Opolon, Paule; Louache, Fawzia; Vassal, Gilles; Laplace-Builhé, Corinne; Vielh, Philippe; Soria, Jean-Charles; Farace, Françoise

    2012-05-01

    The prevailing concept is that immediate mobilization of bone marrow-derived circulating endothelial progenitor cells (CEP) is a key mechanism mediating tumor resistance to vascular-disrupting agents (VDA). Here, we show that administration of VDA to tumor-bearing mice induces 2 distinct peaks in CEPs: an early, unspecific CEP efflux followed by a late yet more dramatic tumor-specific CEP burst that infiltrates tumors and is recruited to vessels. Combination with antiangiogenic drugs could not disrupt the early peak but completely abrogated the late VDA-induced CEP burst, blunted bone marrow-derived cell recruitment to tumors, and resulted in striking antitumor efficacy, indicating that the late CEP burst might be crucial to tumor recovery after VDA therapy. CEP and circulating endothelial cell kinetics in VDA-treated patients with cancer were remarkably consistent with our preclinical data. These findings expand the current understanding of vasculogenic "rebounds" that may be targeted to improve VDA-based strategies. Our findings suggest that resistance to VDA therapy may be strongly mediated by late, rather than early, tumor-specific recruitment of CEPs, the suppression of which resulted in increased VDA-mediated antitumor efficacy. VDA-based therapy might thus be significantly enhanced by combination strategies targeting late CEP mobilization. © 2012 AACR

  6. Expression of DAI by an oncolytic vaccinia virus boosts the immunogenicity of the virus and enhances antitumor immunity

    Directory of Open Access Journals (Sweden)

    Mari Hirvinen

    2016-01-01

    Full Text Available In oncolytic virotherapy, the ability of the virus to activate the immune system is a key attribute with regard to long-term antitumor effects. Vaccinia viruses bear one of the strongest oncolytic activities among all oncolytic viruses. However, its capacity for stimulation of antitumor immunity is not optimal, mainly due to its immunosuppressive nature. To overcome this problem, we developed an oncolytic VV that expresses intracellular pattern recognition receptor DNA-dependent activator of IFN-regulatory factors (DAI to boost the innate immune system and to activate adaptive immune cells in the tumor. We showed that infection with DAI-expressing VV increases expression of several genes related to important immunological pathways. Treatment with DAI-armed VV resulted in significant reduction in the size of syngeneic melanoma tumors in mice. When the mice were rechallenged with the same tumor, DAI-VV-treated mice completely rejected growth of the new tumor, which indicates immunity established against the tumor. We also showed enhanced control of growth of human melanoma tumors and elevated levels of human T-cells in DAI-VV-treated mice humanized with human peripheral blood mononuclear cells. We conclude that expression of DAI by an oncolytic VV is a promising way to amplify the vaccine potency of an oncolytic vaccinia virus to trigger the innate—and eventually the long-lasting adaptive immunity against cancer.

  7. Mechanisms of reduction of antitumor drug toxicity by liposome encapsulation

    Energy Technology Data Exchange (ETDEWEB)

    Rahman, Y. E.; Hanson, W. R.; Bharucha, J.; Ainsworth, E. J.; Jaroslow, B.

    1977-01-01

    The antitumor drug Actinomycin D is effective against the growth of some human solid tumors but its use is limited by its extreme toxicity. The development of a method of administering Act. D to reduce its systemic toxicity by incorporating the drug within liposomes reduced its toxicity but its tumoricidal activity was retained.

  8. Antitumor agent 25-epi Ritterostatin GN1N induces endoplasmic reticulum stress and autophagy mediated cell death in melanoma cells.

    Science.gov (United States)

    Riaz Ahmed, Kausar Begam; Kanduluru, Ananda Kumar; Feng, Li; Fuchs, Philip L; Huang, Peng

    2017-05-01

    Metastatic melanoma is the most aggressive of all skin cancers and is associated with poor prognosis owing to lack of effective treatments. 25-epi Ritterostatin GN1N is a novel antitumor agent with yet undefined mechanisms of action. We sought to delineate the antitumor mechanisms of 25-epi Ritterostatin GN1N in melanoma cells to determine the potential of this compound as a treatment for melanoma. Activation of the endoplasmic reticulum (ER) stress protein glucose-regulated protein 78 (GRP78) has been associated with increased melanoma progression, oncogenic signaling, drug resistance, and suppression of cell death. We found that 25-epi Ritterostatin GN1N induced cell death in melanoma cells at nanomolar concentrations, and this cell death was characterized by inhibition of GRP78 expression, increased expression of the ER stress marker CHOP, loss of mitochondrial membrane potential, and lipidation of the autophagy marker protein LC3B. Importantly, normal melanocytes exhibited limited sensitivity to 25-epi Ritterostatin GN1N. Subsequent in vivo results demonstrated that 25-epi Ritterostatin GN1N reduced melanoma growth in mouse tumor xenografts and did not affect body weight, suggesting minimal toxicity. In summary, our findings indicate that 25-epi Ritterostatin GN1N causes ER stress and massive autophagy, leading to collapse of mitochondrial membrane potential and cell death in melanoma cells, with minimal effects in normal melanocytes. Thus, 25-epi Ritterostatin GN1N is a promising anticancer agent that warrants further investigation.

  9. Enhanced antitumor efficacy of doxorubicin-encapsulated halloysite nanotubes

    Directory of Open Access Journals (Sweden)

    Li K

    2017-12-01

    Full Text Available Kai Li,1,* Yongxing Zhang,2,* Mengting Chen,1 Yangyang Hu,1 Weiliang Jiang,1 Li Zhou,1 Sisi Li,1 Min Xu,1 Qinghua Zhao,2 Rong Wan1 1Department of Gastroenterology, Shanghai First People’s Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, People’s Republic of China; 2Department of Orthopaedics, Shanghai First People’s Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, People’s Republic of China *These authors contributed equally to this work Abstract: To improve the antitumor efficacy of doxorubicin (DOX and provide novel clinical treatment of gastric cancer, halloysite nanotubes (HNTs loaded with DOX were encapsulated by soybean phospholipid (LIP and the formed HNTs/DOX/LIP was systematically characterized via different techniques. The in vitro anticancer activity of HNTs/DOX/LIP was examined using an MTT assay. The antitumor efficacy and biocompatibility were monitored by measuring the tumor volume and assessing the blood routine and serum biochemistry using an ectopic implantation cancer model. The results show that when the concentration of HNTs was 3 mg/mL and the concentration of DOX was 1 mg/mL the optimal DOX loading efficiency was as high as 22.01%±0.43%. In vitro drug release behavior study demonstrated that HNTs/DOX/LIP shows a pH-responsive release property with fast drug release under acidic conditions (pH =5.4. MTT assays and in vivo experimental results revealed that HNTs/DOX/LIP exhibits a significantly higher inhibitory efficacy on the growth of mouse gastric cancer cells than free DOX at the same drug concentration. In addition, the life span of tumor-bearing mice in the HNTs/DOX/LIP-treated group was obviously prolonged compared with the control groups. Moreover, HNTs/DOX/LIP possessed excellent hemocompatibility as shown in the blood and histology studies. These findings indicated that the formed HNTs/DOX/LIP possesses higher antitumor efficacy and may be used as a targeted

  10. Resistance to antitumor chemotherapy due to bounded-noise-induced transitions

    Science.gov (United States)

    D'Onofrio, Alberto; Gandolfi, Alberto

    2010-12-01

    Tumor angiogenesis is a landmark of solid tumor development, but it is also directly relevant to chemotherapy. Indeed, the density and quality of neovessels may influence the effectiveness of therapies based on blood-born agents. In this paper, first we define a deterministic model of antiproliferative chemotherapy in which the drug efficacy is a unimodal function of vessel density, and then we show that under constant continuous infusion therapy the tumor-vessel system may be multistable. However, the actual drug concentration profiles are affected by bounded even if possibly large fluctuations. Through numerical simulations, we show that the tumor volume may undergo transitions to the higher equilibrium value induced by the bounded noise. In case of periodically delivered boli-based chemotherapy, we model the fluctuations due to time variability of both the drug clearance rate and the distribution volume, as well as those due to irregularities in drug delivery. We observed noise-induced transitions also in case of periodic delivering. By applying a time dense scheduling with constant average delivered drug (metronomic scheduling), we observed an easier suppression of the transitions. Finally, we propose to interpret the above phenomena as an unexpected non-genetic kind of resistance to chemotherapy.

  11. An oncofetal glycosaminoglycan modification provides therapeutic access to Cisplatin-resistant bladder cancer

    DEFF Research Database (Denmark)

    Seiler, Roland; Oo, Htoo Zarni; Tortora, Davide

    2017-01-01

    the malaria parasite Plasmodium falciparum, we can target these sugar chains, and our results showed a significant antitumor effect in cisplatin-resistant bladder cancer. This novel treatment paradigm provides therapeutic access to bladder cancers not responding to cisplatin.......BACKGROUND: Although cisplatin-based neoadjuvant chemotherapy (NAC) improves survival of unselected patients with muscle-invasive bladder cancer (MIBC), only a minority responds to therapy and chemoresistance remains a major challenge in this disease setting. OBJECTIVE: To investigate the clinical...... significance of oncofetal chondroitin sulfate (ofCS) glycosaminoglycan chains in cisplatin-resistant MIBC and to evaluate these as targets for second-line therapy. DESIGN, SETTING, AND PARTICIPANTS: An ofCS-binding recombinant VAR2CSA protein derived from the malaria parasite Plasmodium falciparum (rVAR2...

  12. A New in Vitro Anti-Tumor Polypeptide Isolated from Arca inflata

    Directory of Open Access Journals (Sweden)

    Jian Xu

    2013-12-01

    Full Text Available A new in vitro anti-tumor polypeptide, coded as J2-C3, was isolated from Arca inflata Reeve and purified by diethyl-aminoethanol (DEAE-sepharose Fast Flow anion exchange and phenyl sepharose CL-4B hydrophobic chromatography. J2-C3 was identified to be a homogeneous compound by native polyacrylamide gel electrophoresis (Native-PAGE. The purity of J2-C3 was over 99% in reversed phase-high performance liquid chromatography (RP-HPLC. The molecular weight was determined as 20,538.0 Da by electrospray-ionization mass spectrometry (ESI-MS/MS. J2-C3 was rich in Glx (Gln + Glu, Lys, and Asx (Asp + Asn according to amino acid analysis. Four partial amino acid sequences of this peptide were determined as L/ISMEDVEESR, KNGMHSI/LDVNHDGR, AMKI/LI/LNPKKGI/LVPR and AMGAHKPPKGNEL/IGHR via MALDI-TOF/TOF-MS and de novo sequencing. Secondary structural analysis by CD spectroscopy revealed that J2-C3 had the α-helix (45.2%, β-sheet (2.9%, β-turn (26.0% and random coil (25.9%. The anti-tumor effect of J2-C3 against human tumor cells was measured by 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT assay, and the IC50 values of J2-C3 were 65.57, 93.33 and 122.95 µg/mL against A549, HT-29 and HepG2 cell lines, respectively. Therefore, J2-C3 might be developed as a potential anti-tumor agent.

  13. Anti-tumor effect of bisphosphonate (YM529 on non-small cell lung cancer cell lines

    Directory of Open Access Journals (Sweden)

    Date Hiroshi

    2007-01-01

    Full Text Available Abstract Background YM529 is a newly developed nitrogen-containing bisphosphonate (BP classified as a third-generation BP that shows a 100-fold greater potency against bone resorption than pamidronate, a second-generation BP. This agent is, therefore expected to be extremely useful clinically for the treatment of osteoporosis and hypercalcemia. Recently, YM529 as well as other third-generation BPs have also been shown to exert anti-tumor effects against various types of cancer cells both in vitro or/and in vivo. In this study, we investigate the anti-tumor effect of YM529 on non-small cell lung cancer (NSCLC. Methods Direct anti-tumor effect of YM529 against 8 NSCLC cell lines (adenocarcinoma: H23, H1299, NCI-H1819, NCI-H2009, H44, A549, adenosquamous cell carcinoma: NCI-H125, squamous cell carcinoma: NCI-H157 were measured by MTS assay and calculated inhibition concentration 50 % (IC50 values. YM529 induced apoptosis of NCI-H1819 was examined by DNA fragmentation of 2 % agarose gel electrophoresis and flowcytometric analysis (sub-G1 method. We examined where YM529 given effect to apoptosis of NSCLC cells in signaling pathway of the mevalonate pathway by western blotting analysis. Results We found that there was direct anti-tumor effect of YM529 on 8 NSCLC cell lines in a dose-dependent manner and their IC50 values were 2.1 to 7.9 μM and YM529 induced apoptosis and G1 arrest cell cycle with dose-dependent manner and YM529 caused down regulation of phospholyration of ERK1/2 in signaling pathways of NSCLC cell line (NCI-H1819. Conclusion Our study demonstrate that YM529 showed direct anti-tumor effect on NSCLC cell lines in vitro, which supports the possibility that third-generation BPs including YM529 can be one of therapeutic options for NSCLC.

  14. An immunological analysis of natural resistance to moise hepatitis virus (JHMV strain) infection in C3H mice

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, C A; Pickel, K [Wurzburg Univ. (Germany, F.R.). Inst. fuer Virologie und Immunbiologie

    1987-01-01

    Since the development of resistance against mouse hepatitis virus (JHMV strain) coincides with the maturation of the immune system, we studied the possible role of distinct immunological components in the resistance of adult mice during JHMV infection. Adult C3H mice naturally resistant to JHMV were rendered susceptible to infection by lethal {sup 60}Co-irradiation and were subsequently reconstituted with limiting numbers of syngeneic bone marrow cells or spleen cells. Resistance or susceptibility dependend on the number of cells used for reconstitution and the interval between reconsitution and infection. Spleen cells from suckling mice affected neither resistance nor susceptibility and peritoneal cells from adult mice and thymus cells reduced resistance. Persistence of JHMV was demonstrated by virus reactivation. Animals infected with JHMV only once before being rendered immunoincompetent showed a different pattern of resistance. One to four months after infection, 15 to 35% of the animals died after reconstitution without having been reinfected, and persisting JHMV was found in their liver, spleen and peritoneal exudate. The survivors (47 to 87%) were resistant to further JHMV infection during immunodeficiency. Animals immunized 3 times with JHMV before irradiation did not show virus reactivation and were fully resistant to JHMV reinfection after reconstitution. The level of neutralizing anti JHMV serum antibodies in the group of mice immunized only once was comparable with the level of those immunized 3 times. The role of macrophage activation and cell-mediated immunity in this model are discused as an explanation for the resistance to, and persistence of, JHMV. (author).

  15. An immunological analysis of natural resistance to moise hepatitis virus (JHMV strain) infection in C3H mice

    International Nuclear Information System (INIS)

    Pereira, C.A.; Pickel, K.

    1987-01-01

    Since the development of resistance against mouse hepatitis virus (JHMV strain) coincides with the maturation of the immune system, we studied the possible role of distinct immunological components in the resistance of adult mice during JHMV infection. Adult C3H mice naturally resistant to JHMV were rendered susceptible to infection by lethal 60 Co-irradiation and were subsequently reconstituted with limiting numbers of syngeneic bone marrow cells or spleen cells. Resistance or susceptibility dependend on the number of cells used for reconstitution and the interval between reconsitution and infection. Spleen cells from suckling mice affected neither resistance nor susceptibility and peritoneal cells from adult mice and thymus cells reduced resistance. Persistence of JHMV was demonstrated by virus reactivation. Animals infected with JHMV only once before being rendered immunoincompetent showed a different pattern of resistance. One to four months after infection, 15 to 35% of the animals died after reconstitution without having been reinfected, and persisting JHMV was found in their liver, spleen and peritoneal exudate. The survivors (47 to 87%) were resistant to further JHMV infection during immunodeficiency. Animals immunized 3 times with JHMV before irradiation did not show virus reactivation and were fully resistant to JHMV reinfection after reconstitution. The level of neutralizing anti JHMV serum antibodies in the group of mice immunized only once was comparable with the level of those immunized 3 times. The role of macrophage activation and cell-mediated immunity in this model are discused as an explanation for the resistance to, and persistence of, JHMV. (author) [pt

  16. Natural Diversity in Heat Resistance of Bacteria and Bacterial Spores: Impact on Food Safety and Quality.

    Science.gov (United States)

    den Besten, Heidy M W; Wells-Bennik, Marjon H J; Zwietering, Marcel H

    2018-03-25

    Heat treatments are widely used in food processing often with the aim of reducing or eliminating spoilage microorganisms and pathogens in food products. The efficacy of applying heat to control microorganisms is challenged by the natural diversity of microorganisms with respect to their heat robustness. This review gives an overview of the variations in heat resistances of various species and strains, describes modeling approaches to quantify heat robustness, and addresses the relevance and impact of the natural diversity of microorganisms when assessing heat inactivation. This comparison of heat resistances of microorganisms facilitates the evaluation of which (groups of) organisms might be troublesome in a production process in which heat treatment is critical to reducing the microbial contaminants, and also allows fine-tuning of the process parameters. Various sources of microbiological variability are discussed and compared for a range of species, including spore-forming and non-spore-forming pathogens and spoilage organisms. This benchmarking of variability factors gives crucial information about the most important factors that should be included in risk assessments to realistically predict heat inactivation of bacteria and spores as part of the measures for controlling shelf life and safety of food products.

  17. Antitumor evaluation of epigallocatechin gallate by colorimetric methods

    Energy Technology Data Exchange (ETDEWEB)

    Baek, Soon Ok [Korean Ginseng and Tobacco Research institute, Daejon (Korea, Republic of); Kim, Il Kwang; Baek, Seung Hwa; Han, Du Seok [Wonkwang Unvi., Iksan (Korea, Republic of)

    1998-08-01

    In the present study, we were evaluated cytotoxic effects of epigallocatechin gallate in human skin melanoma cells such as HTB-69. The light microscopic study showed morphological changes of the treated cells. Disruptions in cell organelles were determined by colorimetric methods; 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay, neutral red (NR) assay and sulforhodamine B protein (SRB) as-say. These results suggest that epigallocatechin gallate retains a potential antitumor activity.

  18. Characterization of the multiple drug resistance phenotype expressed by tumour cells following in vitro exposure to fractionated X-irradiation

    International Nuclear Information System (INIS)

    Hill, B.T.; McClean, S.; Hosking, L.; Shellard, S.; Dempke, W.; Whelan, R.

    1992-01-01

    The major clinical problem of the emergence of drug resistant tumor cell populations is recognized in patients previously treated with antitumor drugs and with radiotherapy. It is proposed that, although radiation-induced vascular fibrosis may limit drug delivery to the tumor, exposure to radiation may 'induce' or 'select for' drug resistance. This hypothesis was examined by establishing in vitro model systems to investigate the resistance phenotype of tumor cells following exposure to X-rays. Characteristically tumor cells surviving exposure to a series of fractions of X-irradiation are shown to have consistently expressed resistance to multiple drugs, including the Vinca alkaloids and the epipodophyllotoxins. Currently this research is aimed at determining whether distinctive resistance mechanisms operate depending on whether resistance results following drug or X-ray exposure. Initial results indicate that whilst some common mechanisms operate, drug resistant tumor cells identified following exposure to X-irradiation appear to exhibit a novel multidrug resistance phenotype. (author). 13 refs., 1 tab

  19. Resistance to Degradation and Cellular Distribution are Important Features for the Antitumor Activity of Gomesin

    Science.gov (United States)

    Buri, Marcus V.; Domingues, Tatiana M.; Paredes-Gamero, Edgar J.; Casaes-Rodrigues, Rafael L.; Rodrigues, Elaine Guadelupe; Miranda, Antonio

    2013-01-01

    Many reports have shown that antimicrobial peptides exhibit anticancer abilities. Gomesin (Gm) exhibits potent cytotoxic activity against cancer cells by a membrane pore formation induced after well-orchestrated intracellular mechanisms. In this report, the replacements of the Cys by Ser or Thr, and the use D-amino acids in the Gm structure were done to investigate the importance of the resistance to degradation of the molecule with its cytotoxicity. [Thr2,6,11,15]-Gm, and [Ser2,6,11,15]-Gm exhibits low cytotoxicity, and low resistance to degradation, and after 24 h are present in localized area near to the membrane. Conversely, the use of D-amino acids in the analogue [D-Thr2,6,11,15]-D-Gm confers resistance to degradation, increases its potency, and maintained this peptide spread in the cytosol similarly to what happens with Gm. Replacements of Cys by Thr and Gln by L- or D-Pro ([D-Thr2,6,11,15, Pro9]-D-Gm, and [Thr2,6,11,15, D-Pro9]-Gm), which induced a similar β-hairpin conformation, also increase their resistance to degradation, and cytotoxicity, but after 24 h they are not present spread in the cytosol, exhibiting lower cytotoxicity in comparison to Gm. Additionally, chloroquine, a lysosomal enzyme inhibitor potentiated the effect of the peptides. Furthermore, the binding and internalization of peptides was determined, but a direct correlation among these factors was not observed. However, cholesterol ablation, which increase fluidity of cellular membrane, also increase cytotoxicity and internalization of peptides. β-hairpin spatial conformation, and intracellular localization/target, and the capability of entry are important properties of gomesin cytotoxicity. PMID:24312251

  20. Resistance to degradation and cellular distribution are important features for the antitumor activity of gomesin.

    Directory of Open Access Journals (Sweden)

    Marcus V Buri

    Full Text Available Many reports have shown that antimicrobial peptides exhibit anticancer abilities. Gomesin (Gm exhibits potent cytotoxic activity against cancer cells by a membrane pore formation induced after well-orchestrated intracellular mechanisms. In this report, the replacements of the Cys by Ser or Thr, and the use D-amino acids in the Gm structure were done to investigate the importance of the resistance to degradation of the molecule with its cytotoxicity. [Thr(2,6,11,15]-Gm, and [Ser(2,6,11,15]-Gm exhibits low cytotoxicity, and low resistance to degradation, and after 24 h are present in localized area near to the membrane. Conversely, the use of D-amino acids in the analogue [D-Thr(2,6,11,15]-D-Gm confers resistance to degradation, increases its potency, and maintained this peptide spread in the cytosol similarly to what happens with Gm. Replacements of Cys by Thr and Gln by L- or D-Pro ([D-Thr(2,6,11,15, Pro(9]-D-Gm, and [Thr(2,6,11,15, D-Pro(9]-Gm, which induced a similar β-hairpin conformation, also increase their resistance to degradation, and cytotoxicity, but after 24 h they are not present spread in the cytosol, exhibiting lower cytotoxicity in comparison to Gm. Additionally, chloroquine, a lysosomal enzyme inhibitor potentiated the effect of the peptides. Furthermore, the binding and internalization of peptides was determined, but a direct correlation among these factors was not observed. However, cholesterol ablation, which increase fluidity of cellular membrane, also increase cytotoxicity and internalization of peptides. β-hairpin spatial conformation, and intracellular localization/target, and the capability of entry are important properties of gomesin cytotoxicity.

  1. Resistance to degradation and cellular distribution are important features for the antitumor activity of gomesin.

    Science.gov (United States)

    Buri, Marcus V; Domingues, Tatiana M; Paredes-Gamero, Edgar J; Casaes-Rodrigues, Rafael L; Rodrigues, Elaine Guadelupe; Miranda, Antonio

    2013-01-01

    Many reports have shown that antimicrobial peptides exhibit anticancer abilities. Gomesin (Gm) exhibits potent cytotoxic activity against cancer cells by a membrane pore formation induced after well-orchestrated intracellular mechanisms. In this report, the replacements of the Cys by Ser or Thr, and the use D-amino acids in the Gm structure were done to investigate the importance of the resistance to degradation of the molecule with its cytotoxicity. [Thr(2,6,11,15)]-Gm, and [Ser(2,6,11,15)]-Gm exhibits low cytotoxicity, and low resistance to degradation, and after 24 h are present in localized area near to the membrane. Conversely, the use of D-amino acids in the analogue [D-Thr(2,6,11,15)]-D-Gm confers resistance to degradation, increases its potency, and maintained this peptide spread in the cytosol similarly to what happens with Gm. Replacements of Cys by Thr and Gln by L- or D-Pro ([D-Thr(2,6,11,15), Pro(9)]-D-Gm, and [Thr(2,6,11,15), D-Pro(9)]-Gm), which induced a similar β-hairpin conformation, also increase their resistance to degradation, and cytotoxicity, but after 24 h they are not present spread in the cytosol, exhibiting lower cytotoxicity in comparison to Gm. Additionally, chloroquine, a lysosomal enzyme inhibitor potentiated the effect of the peptides. Furthermore, the binding and internalization of peptides was determined, but a direct correlation among these factors was not observed. However, cholesterol ablation, which increase fluidity of cellular membrane, also increase cytotoxicity and internalization of peptides. β-hairpin spatial conformation, and intracellular localization/target, and the capability of entry are important properties of gomesin cytotoxicity.

  2. Effect of immunomodifier on radiation-induced antitumor immunity following local irradiation to tumor, 2

    International Nuclear Information System (INIS)

    Mukae, Shiro; Norimura, Toshiyuki; Tsuchiya, Takehiko

    1988-01-01

    This study was carried out to clarify whether or not the antitumor cell-mediated immunity of host is more effectively induced by the combined use of mouse interferon-α/β (MuIFN-α/β) with local irradiation than by simple local irradiation to tumor. C3H/He female mice, MM46 tumor cells and mouse interferon-α/β (MuIFN-α/β) were used in the experiment. Antitumor activity in mice was evaluated by the inhibition of tumor growth and mean survival days after treatment. Spleen cell killing activity to MM46 tumor cells was measured to evaluate the antitumor activity in vitro. In the case of single use of MuIFN-α/β, tumor growth was more rapid than in the non-treated group (control) in vivo. The mean survival days were also reduced. There was no siginificant difference in tumor growth inhibition between combined therapy using X-irradiation and MuIFN-α/β, and single therapy by local irradiation. However, in the case of administration of MuIFN-α/β after irradiation, the mean survival days was significantly increased compared with the group receiving X-ray irradiation only. (author)

  3. Dual PI3K/mTOR inhibitor BEZ235 as a promising therapeutic strategy against paclitaxel-resistant gastric cancer via targeting PI3K/Akt/mTOR pathway.

    Science.gov (United States)

    Chen, Dongshao; Lin, Xiaoting; Zhang, Cheng; Liu, Zhentao; Chen, Zuhua; Li, Zhongwu; Wang, Jingyuan; Li, Beifang; Hu, Yanting; Dong, Bin; Shen, Lin; Ji, Jiafu; Gao, Jing; Zhang, Xiaotian

    2018-01-26

    Paclitaxel (PTX) is widely used in the front-line chemotherapy for gastric cancer (GC), but resistance limits its use. Due to the lack of proper models, mechanisms underlying PTX resistance in GC were not well studied. Using established PTX-resistant GC cell sublines HGC-27R, we for the first time integrated biological traits and molecular mechanisms of PTX resistance in GC. Data revealed that PTX-resistant GC cells were characterized by microtubular disorders, an EMT phenotype, reduced responses to antimitotic drugs, and resistance to apoptosis (marked by upregulated β-tubulin III, vimentin, attenuated changes in G 2 /M molecules or pro-apoptotic factors in response to antimitotic drugs or apoptotic inducers, respectively). Activation of the phosphoinositide 3-kinase, the serine/threonine kinase Akt and mammalian target of rapamycin (PI3K/Akt/mTOR) and mitogen-activated protein kinase (MAPK) pathways were also observed, which might be the reason for above phenotypic alternations. In vitro data suggested that targeting these pathways were sufficient to elicit antitumor responses in PTX-resistant GC, in which the dual PI3K/mTOR inhibitor BEZ235 displayed higher therapeutic efficiency than the mTOR inhibitor everolimus or the MEK inhibitor AZD6244. Antitumor effects of BEZ235 were also confirmed in mice bearing HGC-27R tumors. Thus, these data suggest that PI3K/Akt/mTOR and MAPK pathway inhibition, especially PI3K/mTOR dual blockade, might be a promising therapeutic strategy against PTX-resistant GC.

  4. Antitumor and antimicrobial activities and inhibition of in-vitro lipid ...

    African Journals Online (AJOL)

    The antitumor activity was measured in DLA cell line induced mice. Inhibition of in vitro lipid peroxidation activity of the D. nobile in both liver homogenate and RBC ghosts was also carried out. The aqueous extracts of stem and flower of D. nobile showed better zone of bacterial inhibition than that of ethanol and chloroform

  5. Poly(γ-glutamic acid)-coated lipoplexes loaded with Doxorubicin for enhancing the antitumor activity against liver tumors

    Science.gov (United States)

    Qi, Na; Tang, Bo; Liu, Guang; Liang, Xingsi

    2017-05-01

    The study was to develop poly-γ-glutamic acid (γ-PGA)-coated Doxorubicin (Dox) lipoplexes that enhance the antitumor activity against liver tumors. γ-PGA-coated lipoplexes were performed by electrostatistically attracting to the surface of cationic charge liposomes with anionic γ-PGA. With the increasing of γ-PGA concentration, the particle size of γ-PGA-coated Dox lipoplexes slightly increased, the zeta potential from positive shifted to negative, and the entrapment efficiency (EE) were no significant change. The release rate of γ-PGA-coated Dox lipoplexes slightly increased at acidic pH, the accelerated Dox release might be attributed to greater drug delivery to tumor cells, resulting in a higher antitumor activity. Especially, γ-PGA-coated Dox lipoplexes exhibited higher cellular uptake, significant in vitro cytotoxicity in HepG2 cells, and improved in vivo antitumor efficacy toward HepG2 hepatoma-xenografted nude models in comparison with Dox liposomes and free Dox solution. In addition, the analysis results via flow cytometry showed that γ-PGA-coated Dox lipoplexes induce S phase cell cycle arrest and significantly increased apoptosis rate of HepG2 cells. In conclusion, the presence of γ-PGA on the surface of Dox lipoplexes enhanced antitumor effects of liver tumors.

  6. Resistência natural de seis espécies de madeiras da região amazônica a fungos apodrecedores, em ensaios de laboratório

    Directory of Open Access Journals (Sweden)

    Marcus Vinicius Da Silva Alves

    2006-01-01

    Full Text Available This study evaluated the natural resistance of six Amazonian wood species: Aspidosperma desmanthum (Araracanga, Parinari excelsa (Parinari, Mouriri callocarpa (Miraúba, Marmaroxylon racemosum (Angelim-rajado, Peltogyne paniculata (Roxinho e Astronium sp. (Muiracatiara against Pycnoporus sanguineous, a white rot fungus, and Gloeophyllum trabeum, a brown rot fungus. Testing was performed based on the American Society for Testing and Materials - Standard Method for Accelerated Laboratory Test of Natural Decay Resistance of Woods - ASTM D2017/81(86. Results showed that all tested wood species were classified as very resistant to both decay fungi, except the wood of Aspidosperma desmanthum, which demonstrated to be very resistant to Pycnoporus sanguineous and resistant to Gloeophyllum trabeum. The wood of Peltogyne paniculata showed the best performance against Pycnoporus sanguineous, whereas the wood of Astronium sp. presented the best results when submitted to Gloeophyllum trabeum attack.

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

    International Nuclear Information System (INIS)

    Hwang, Kyung-Sun; Cho, Won-Kyung; Yoo, Jinsang; Yun, Hwan-Jung; Kim, Samyong; Im, Dong-Soo

    2005-01-01

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

  8. Effects of extraction methods on the yield, chemical structure and anti-tumor activity of polysaccharides from Cordyceps gunnii mycelia.

    Science.gov (United States)

    Zhu, Zhen-Yuan; Dong, Fengying; Liu, Xiaocui; Lv, Qian; YingYang; Liu, Fei; Chen, Ling; Wang, Tiantian; Wang, Zheng; Zhang, Yongmin

    2016-04-20

    This study was to investigate the effects of different extraction methods on the yield, chemical structure and antitumor activity of polysaccharides from Cordyceps gunnii (C. gunnii) mycelia. Five extraction methods were used to extract crude polysaccharides (CPS), which include room-temperature water extraction (RWE), hot-water extraction (HWE), microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE) and cellulase-assisted extraction (CAE). Then Sephadex G-100 was used for purification of CPS. As a result, the antitumor activities of CPS and PPS on S180 cells were evaluated. Five CPS and purified polysaccharides (PPS) were obtained. The yield of CPS by microwave-assisted extraction (CPSMAE) was the highest and its anti-tumor activity was the best and its macromolecular polysaccharide (3000-1000kDa) ratio was the largest. The PPS had the same monosaccharide composition, but their obvious difference was in the antitumor activity and the physicochemical characteristics, such as intrinsic viscosity, specific rotation, scanning electron microscopy and circular dichroism spectra. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. In vitro and in vivo antitumor effects of 50 to 100-KDa components from B16 melanoma culture supernatant.

    Science.gov (United States)

    Qin, Ying-Song; Zhang, X U; Zhang, Xiang-Yu

    2015-07-01

    The development of immunological therapies for melanoma has been of considerable concern in recent years. Whole tumor cell lysates have been used to develop antitumor vaccines, but the effective components of the lysates have not been identified. In the present study, protein elements were purified from the B16 supernatant to analyze the in vitro chemotaxis towards mouse spleen lymphocytes using a Boyden chamber. Prior to establishing a B16 melanoma model, C57BL/6 mice were vaccinated with these proteins, and melanoma growth, tumor appearance time and behavioral changes were observed. Next, the cytotoxicity and subsets of the tumor infiltrating lymphocytes, and the histological characteristics of the melanoma were analyzed. The isolated purified fragments of B16 melanoma culture supernatant had strong antitumor effects. The possible antitumor mechanism was delineated, and was identified to possibly be through the activation of cluster of differentiation 8-positive T cells and the promotion of B16 cell differentiation. These methods will provide a novel insight into understanding antitumor immunological mechanisms and provide a potential avenue for immunotherapy.

  10. Possible Therapeutic Application of Targeting Type II Natural Killer T Cell-Mediated Suppression of Tumor Immunity

    Science.gov (United States)

    Kato, Shingo; Berzofsky, Jay A.; Terabe, Masaki

    2018-01-01

    Natural killer T (NKT) cells are a unique T cell subset that exhibits characteristics from both the innate immune cells and T cells. There are at least two subsets of NKT cells, type I and type II. These two subsets of NKT cells have opposite functions in antitumor immunity. Type I NKT cells usually enhance and type II NKT cells suppress antitumor immunity. In addition, these two subsets of NKT cells cross-regulate each other. In this review, we mainly focus on immunosuppressive NKT cells, type II NKT cells. After summarizing their definition, experimental tools to study them, and subsets of them, we will discuss possible therapeutic applications of type II NKT cell pathway targeted therapies. PMID:29520281

  11. Antitumor Properties of the Essential Oil From the Leaves of Duguetia gardneriana.

    Science.gov (United States)

    Rodrigues, Ana Carolina B C; Bomfim, Larissa M; Neves, Sara P; Menezes, Leociley R A; Dias, Rosane B; Soares, Milena B P; Prata, Ana Paula N; Rocha, Clarissa A Gurgel; Costa, Emmanoel V; Bezerra, Daniel P

    2015-07-01

    Duguetia gardneriana, popularly known in the Brazilian northeast as "jaquinha", is a species belonging to the family Annonaceae. The aim of this work was to assess the chemical composition and antitumor properties of the essential oil from the leaves of D. gardneriana in experimental models. The chemical composition of the essential oil was analyzed via gas chromatography-flame ionization detector and gas chromatography-mass spectrometry. In vitro cytotoxic activity was determined in cultured tumor cells, and in vivo antitumor activity was assessed in B16-F10-bearing mice. The identified compounds were β-bisabolene (80.99%), elemicin (8.04%), germacrene D (4.15%), and cyperene (2.82%). The essential oil exhibited a cytotoxic effect, with IC50 values of 16.89, 19.16, 13.08, and 19.33 µg/mL being obtained for B16-F10, HepG2, HL-60, and K562 cell lines, respectively. On the other hand, β-bisabolene was inactive in all of the tested tumor cell lines (showing IC50 values greater than 25 µg/mL). The in vivo analysis revealed tumor growth inhibition rates of 5.37-37.52% at doses of 40 and 80 mg/kg/day, respectively. Herein, the essential oil from the leaves of D. gardneriana presented β-bisabolene as the major constituent and showed cytotoxic and antitumor potential. Georg Thieme Verlag KG Stuttgart · New York.

  12. Antitumor effect of the essential oil from leaves of Guatteria pogonopus (Annonaceae).

    Science.gov (United States)

    do N Fontes, José Eraldo; Ferraz, Rosana P C; Britto, Anny C S; Carvalho, Adriana A; Moraes, Manoel O; Pessoa, Claudia; Costa, Emmanoel V; Bezerra, Daniel P

    2013-04-01

    Guatteria pogonopus Martius, a plant belonging to the Annonaceae family, is found in the remaining Brazilian Atlantic Forest. In this study, the chemical composition and antitumor effects of the essential oil isolated from leaves of G. pogonopus was investigated. The chemical composition of the oil was determined by GC-FID and GC/MS analyses. The in vitro cytotoxicity was evaluated against three different tumor cell lines (OVCAR-8, NCI-H358M, and PC-3M), and the in vivo antitumor activity was tested in mice bearing sarcoma 180 tumor. A total of 29 compounds was identified and quantified in the oil. The major compounds were γ-patchoulene (13.55%), (E)-caryophyllene (11.36%), β-pinene (10.37%), germacrene D (6.72%), bicyclogermacrene (5.97%), α-pinene (5.33%), and germacrene B (4.69%). The essential oil, but neither (E)-caryophyllene nor β-pinene, displayed in vitro cytotoxicity against all three tumor cell lines tested. The obtained average IC50 values ranged from 3.8 to 20.8 μg/ml. The lowest and highest values were obtained against the NCI-H358M and the OVCAR-8 cell lines, respectively. The in vivo tumor-growth-inhibition rates in the tumor-bearing mice treated with essential oil (50 and 100 mg/kg/d) were 25.3 and 42.6%, respectively. Hence, the essential oil showed significant in vitro and in vivo antitumor activity. Copyright © 2013 Verlag Helvetica Chimica Acta AG, Zürich.

  13. Synthesis and antitumor evaluation of arctigenin derivatives based on antiausterity strategy.

    Science.gov (United States)

    Kudou, Naoki; Taniguchi, Akira; Sugimoto, Kenji; Matsuya, Yuji; Kawasaki, Masashi; Toyooka, Naoki; Miyoshi, Chika; Awale, Suresh; Dibwe, Dya Fita; Esumi, Hiroyasu; Kadota, Shigetoshi; Tezuka, Yasuhiro

    2013-02-01

    A series of new (-)-arctigenin derivatives with variably modified O-alkyl groups were synthesized and their preferential cytotoxicity was evaluated against human pancreatic cancer cell line PANC-1 under nutrient-deprived conditions. The results showed that monoethoxy derivative 4i (PC(50), 0.49 μM), diethoxy derivative 4h (PC(50), 0.66 μM), and triethoxy derivative 4m (PC(50), 0.78 μM) showed the preferential cytotoxicities under nutrient-deprived conditions, which were identical to or more potent than (-)-arctigenin (1) (PC(50), 0.80 μM). Among them, we selected the triethoxy derivative 4m and examined its in vivo antitumor activity using a mouse xenograft model. Triethoxy derivative 4m exhibited also in vivo antitumor activity with the potency identical to or slightly more than (-)-arctigenin (1). These results would suggest that a modification of (-)-arctigenin structure could lead to a new drug based on the antiausterity strategy. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  14. A Novel Time-Dependent CENP-E Inhibitor with Potent Antitumor Activity.

    Directory of Open Access Journals (Sweden)

    Akihiro Ohashi

    Full Text Available Centromere-associated protein E (CENP-E regulates both chromosome congression and the spindle assembly checkpoint (SAC during mitosis. The loss of CENP-E function causes chromosome misalignment, leading to SAC activation and apoptosis during prolonged mitotic arrest. Here, we describe the biological and antiproliferative activities of a novel small-molecule inhibitor of CENP-E, Compound-A (Cmpd-A. Cmpd-A inhibits the ATPase activity of the CENP-E motor domain, acting as a time-dependent inhibitor with an ATP-competitive-like behavior. Cmpd-A causes chromosome misalignment on the metaphase plate, leading to prolonged mitotic arrest. Treatment with Cmpd-A induces antiproliferation in multiple cancer cell lines. Furthermore, Cmpd-A exhibits antitumor activity in a nude mouse xenograft model, and this antitumor activity is accompanied by the elevation of phosphohistone H3 levels in tumors. These findings demonstrate the potency of the CENP-E inhibitor Cmpd-A and its potential as an anticancer therapeutic agent.

  15. Cisplatin carbonato complexes. Implications for uptake, antitumor properties, and toxicity.

    Science.gov (United States)

    Centerwall, Corey R; Goodisman, Jerry; Kerwood, Deborah J; Dabrowiak, James C

    2005-09-21

    The reaction of aquated cisplatin with carbonate which is present in culture media and blood is described. The first formed complex is a monochloro monocarbonato species, which upon continued exposure to carbonate slowly forms a biscarbonato complex. The formation of carbonato species under conditions that simulate therapy may have important implications for uptake, antitumor properties, and toxicity of cisplatin.

  16. Antitumor potential of 1-thiocarbamoyl-3,5-diaryl-4,5-dihydro-1H-pyrazoles in human bladder cancer cells.

    Science.gov (United States)

    Tessmann, Josiane Weber; Buss, Julieti; Begnini, Karine Rech; Berneira, Lucas Moraes; Paula, Favero Reisdorfer; de Pereira, Claudio Martin Pereira; Collares, Tiago; Seixas, Fabiana Kömmling

    2017-10-01

    Bladder cancer is a genitourinary malignant disease common worldwide. Current chemotherapy is often limited mainly due to toxicity and drug resistance. Thus, there is a continued need to discover new therapies. Recently evidences shows that pyrazoline derivatives are promising antitumor agents in many types of cancers, but there are no studies with bladder cancer. In order to find potent and novel chemotherapy drugs for bladder cancer, a series of pyrazoline derivatives 2a-2d were tested for their antitumor activity in two human bladder cancer cell lines 5647 and T24. The MTT assay showed that the compounds 1-thiocarbamoyl-3,5-diphenyl-4,5-dihydro-1H-pyrazole (2a) and 1-thiocarbamoyl-5-(4-chlorophenyl)-3-phenyl-4,5-dihydro-1H-pyrazole (2c) decrease the cell viability of 5637 cells. Molecular modeling indicated that these compounds had a good oral bioavailability and low toxicities. Clonogenic assay and flow cytometric analysis were used to assess colony formation, apoptosis induction and cell cycle distribution. Overall, our results suggest that pyrazoline 2a and 2c, with the substituents hydrogen and chlorine respectively, may decrease cell viability and colony formation of bladder cancer 5637 cell line by inhibition of cell cycle progression, and for pyrazoline 2a, by induction of apoptosis. As indicated by the physicochemical properties of these compounds, the steric factor influences the activity. Therefore, these pyrazoline derivatives can be considered promising anticancer agents for the treatment of bladder cancer. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  17. T lymphocytes derived from human cord blood provide effective antitumor immunotherapy against a human tumor

    Directory of Open Access Journals (Sweden)

    Kim Tae-Sik

    2011-06-01

    Full Text Available Abstract Background Although the graft-versus-tumor (GVT effect of donor-derived T cells after allogeneic hematopoietic stem cell transplantation has been used as an effective adoptive immunotherapy, the antitumor effects of cord blood (CB transplantation have not been well studied. Methods We established the animal model by transplantation of CB mononuclear cells and/or tumor cells into NOD/SCID mice. The presence of CB derived T cells in NOD/SCID mice or tumor tissues were determined by flow cytometric and immunohistochemical analysis. The anti-tumor effects of CB derived T cells against tumor was determined by tumor size and weight, and by the cytotoxicity assay and ELISPOT assay of T cells. Results We found dramatic tumor remission following transfer of CB mononuclear cells into NOD/SCID mice with human cervical tumors with a high infiltration of CD3+ T cells in tumors. NOD/SCID mice that receive neonatal CB transplants have reconstituted T cells with significant antitumor effects against human cervical and lung tumors, with a high infiltration of CD3+ T cells showing dramatic induction of apoptotic cell death. We also confirmed that T cells showed tumor specific antigen cytotoxicity in vitro. In adoptive transfer of CD3+ T cells into mice with pre-established tumors, we observed much higher antitumor effects of HPV-specific T cells by ELISPOT assays. Conclusions Our results show that CB derived T lymphocytes will be useful for novel immunotherapeutic candidate cells for therapy of several tumors in clinic.

  18. Resistance to wildfire and early regeneration in natural broadleaved forest and pine plantation

    Science.gov (United States)

    Proença, Vânia; Pereira, Henrique M.; Vicente, Luís

    2010-11-01

    The response of an ecosystem to disturbance reflects its stability, which is determined by two components: resistance and resilience. We addressed both components in a study of early post-fire response of natural broadleaved forest ( Quercus robur, Ilex aquifolium) and pine plantation ( Pinus pinaster, Pinus sylvestris) to a wildfire that burned over 6000 ha in NW Portugal. Fire resistance was assessed from fire severity, tree mortality and sapling persistence. Understory fire resistance was similar between forests: fire severity at the surface level was moderate to low, and sapling persistence was low. At the canopy level, fire severity was generally low in broadleaved forest but heterogeneous in pine forest, and mean tree mortality was significantly higher in pine forest. Forest resilience was assessed by the comparison of the understory composition, species diversity and seedling abundance in unburned and burned plots in each forest type. Unburned broadleaved communities were dominated by perennial herbs (e.g., Arrhenatherum elatius) and woody species (e.g., Hedera hibernica, Erica arborea), all able to regenerate vegetatively. Unburned pine communities presented a higher abundance of shrubs, and most dominant species relied on post-fire seeding, with some species also being able to regenerate vegetatively (e.g., Ulex minor, Daboecia cantabrica). There were no differences in diversity measures in broadleaved forest, but burned communities in pine forest shared less species and were less rich and diverse than unburned communities. Seedling abundance was similar in burned and unburned plots in both forests. The slower reestablishment of understory pine communities is probably explained by the slower recovery rate of dominant species. These findings are ecologically relevant: the higher resistance and resilience of native broadleaved forest implies a higher stability in the maintenance of forest processes and the delivery of ecosystem services.

  19. FACTORS AFFECTING VARIABILITY OF RESISTANCE IN GAROLE SHEEP NATURALLY INFECTED WITH HAEMONCHUS CONTORTUS

    Directory of Open Access Journals (Sweden)

    Manoranjan Roy

    2013-06-01

    Full Text Available Resistance status against natural infection to Haemonchus contortus as well as influence of season, sex, body weight, and haemoglobin type on resistance levels were evaluated in 309 numbers of Garole sheep. In adult Garole sheep, egg per gram(EPG of faeces for Haemonchus contortus was varied from 300 to 1600, but overall EPG in Garole have been recorded as 829.96 ± 20.60. The effects of season, sex, and body weight and haemoglobin type on EPG were all found to be highly significant (P < 0.01. EPG count was highest during monsoon (986.27 ± 28.26, followed by summer (832.88 ± 28.26 and lowest during winter (670.74 ± 28.26 which indicated the existence of a seasonal variation of EPG. Rams had higher EPG (954.32 ± 57.93 than ewes (705.60 ± 45.79 which reflected that males appeared to be more susceptible to Haemonchus contortus infection compared to females. Animals with lower body weight (upto 10 kg showed higher EPG (1017.20 ± 54.82, then the infection level decreased as body weight increased (886.79 ± 56.23 for 10 kg to 12 kg and 737.18 ± 50.29 for 12 kg to 14 kg and lowest EPG was recorded in animals with above 14 kg body weight (678.68 ± 54.49. This study reveals Hb-BB type animals had higher EPG count (983.81 ± 18.22 in comparison to Hb-AB type animals (676.12 ± 33.96 indicating that Haemoglobin-A locus has some relation with resistance. From our study it can be concluded that resistant level of Garole sheep against Haemonchus contortus is influenced by some intrinsic factors like sex, body weight, and haemoglobin type of the sheep and also by extrinsic factor like season.

  20. Antimicrobial resistance and phylogenetic groups in isolates of Escherichia coli from seagulls at the Berlengas nature reserve.

    Science.gov (United States)

    Radhouani, H; Poeta, P; Igrejas, G; Gonçalves, A; Vinué, L; Torres, C

    2009-08-01

    Fifty-three faecal samples from yellow-legged gulls (Larus cachinnans) at the Berlengas nature reserve in Portugal were cultured on Levine agar plates not supplemented with antimicrobial agents, and one Escherichia coli colony was isolated and identified from each sample. The percentages of resistant isolates for each of the drugs were ampicillin (43.4 per cent), tetracycline (39.6 per cent), nalidixic acid (34.0 per cent), streptomycin (32.1 per cent), trimethoprim-sulfamethoxazole (SXT) (26.4 per cent), ciprofloxacin (18.9 per cent), chloramphenicol (18.9 per cent), gentamicin (7.5 per cent), tobramycin (7.5 per cent) amikacin (5.7 per cent) and amoxicillin-clavulanic acid (1.9 per cent). All the isolates were susceptible to cefoxitin, ceftazidime, cefotaxime, aztreonam and imipenem. The following resistance genes were detected: bla(TEM) (17 of 23 ampicillin-resistant isolates), tet(A) and/or tet(B) (18 of 21 tetracycline-resistant isolates), aadA (12 of 17 streptomycin-resistant isolates), cmlA (all chloramphenicol-resistant isolates), aac(3)-II with or without aac(3)-IV (all four gentamicin-resistant isolates), and sul1 and/or sul2 and/or sul3 (all 14 SXT-resistant isolates). The intI1 gene was detected in 10 of 14 SXT-resistant isolates, and three of them also contained class 2 integrons; four different gene cassette arrangements were identified among class 1 integrons (aadA, dfrA1+aadA1, dfrA12+orfF+aadA2 and sat+psp+aadA2) and one among the class 2 integrons (dfrA1+sat+aadA1). Ninety per cent of the isolates were included in the A or B1 phylogenetic groups.

  1. Antitumor Activity of Monoterpenes Found in Essential Oils

    Directory of Open Access Journals (Sweden)

    Marianna Vieira Sobral

    2014-01-01

    Full Text Available Cancer is a complex genetic disease that is a major public health problem worldwide, accounting for about 7 million deaths each year. Many anticancer drugs currently used clinically have been isolated from plant species or are based on such substances. Accumulating data has revealed anticancer activity in plant-derived monoterpenes. In this review the antitumor activity of 37 monoterpenes found in essential oils is discussed. Chemical structures, experimental models, and mechanisms of action for bioactive substances are presented.

  2. Recent advance on the antitumor and antioxidant activity of grape seed extracts

    Directory of Open Access Journals (Sweden)

    Zhu FM

    2015-05-01

    Full Text Available Fengmei Zhu, Bin Du, Jun Li College of Food Science and Technology, Hebei Normal University of Science and Technology, Qinhuangdao, Hebei Province, People's Republic of China Abstract: The grape pomace (including seeds and stems poses potential disposal and pollution problems along with loss of valuable biomass and nutrients. The utilization of grape seeds processing as a source of functional ingredients is a promising field. Grape seed extract provides a concentrated source of polyphenols. Grape seed extract is known as an effective antioxidant that protects the body from premature aging and disease. A number of phytochemicals including resveratrol, proanthocyanidins, etc, have demonstrated significant benefits in cancer chemoprevention. In this review, we summarize the existing knowledge on the antitumor and antioxidant activity of grape seeds polyphenols. Keywords: grape seed, antitumor activity, antioxidant activity, polyphenol, proanthocyanidin

  3. Antitumor effects of metformin via indirect inhibition of protein phosphatase 2A in patients with endometrial cancer.

    Directory of Open Access Journals (Sweden)

    Shinsuke Hanawa

    Full Text Available Metformin, an antidiabetic drug, inhibits the endometrial cancer cell growth in vivo by improving the insulin resistance; however, its mechanism of action is not completely understood. Protein phosphatase 2A (PP2A is a serine/threonine phosphatase associated with insulin resistance and type 2 diabetes, and its inhibition restores the insulin resistance. This study investigated the antitumor effect of metformin on endometrial cancer with a focus on PP2A.Metformin (1,500-2,250 mg/day was preoperatively administered to patients with endometrial cancer for 4 to 6 weeks. Expression of the PP2A regulatory subunits, 4 (PPP2R4 and B (PP2A-B, was evaluated using real-time polymerase chain reaction (RT-PCR and immunohistochemistry (IHC using paired specimens obtained before and after metformin treatment. The effect of PPP2R4 inhibition with small interfering RNA was evaluated in the endometrial cancer cell lines HEC265 and HEC1B. P values of < .05 were considered statistically significant.Preoperative metformin treatment significantly reduced the expression of PP2A-B, as determined using IHC, and the mRNA expression of PPP2R4, as determined using RT-PCR, in the patients with endometrial cancer. However, metformin could not directly alter the PPP2R4 mRNA levels in the endometrial cancer cell lines in vitro. PPP2R4 knockdown reduced the proliferation and induced the apoptosis by activating caspases 3/7 in HEC265 and HEC1B cells.Downregulation of the PP2A-B subunit, including PPP2R4, is an important indirect target of metformin. Inhibition of PP2A may be an option for the treatment of endometrial cancer patients with insulin resistance.This trial is registered with UMIN-CTR (number UMIN000004852.

  4. miR-133b down-regulates ABCC1 and enhances the sensitivity of CRC to anti-tumor drugs.

    Science.gov (United States)

    Chen, Miao; Li, Daojiang; Gong, Ni; Wu, Hao; Su, Chen; Xie, Canbin; Xiang, Hong; Lin, Changwei; Li, Xiaorong

    2017-08-08

    Multidrug resistance (MDR) is the main cause of failed chemotherapy treatments. Therefore, preventing MDR is pivotal in treating colorectal cancer (CRC). In a previous study miR-133b was shown to be a tumor suppressor. Additionally, in CRC cells transfected with miR-133b, ATP-binding cassette (ABC) subfamily C member 1(ABCC1) was shown to be significantly down regulated. Whether miR-133b also enhances the chemosensitivity of drugs used to treat CRC by targeting ABCC1 is still unclear. Here, we utilized flow cytometry and high-performance liquid chromatography (HPLC) analysis to identify the ability of miR-133b to reserve MDR in CRC. We then used a dual-luciferase reporter assay to validate that miR-133b targets ABCC1. Further in vivo experiments were designed to validate the method in which miR-133b reversed MDR in CRC cells. The results demonstrated that the level of miR-133b was down-regulated and the expression of ABCC1 was up-regulated in drug-resistant CRC cells compared to non-drug-resistant CRC cells. The restoration of miR-133b expression in CRC drug-resistant cells in vitro resulted in reduced IC50s to chemotherapeutic drugs, significantly induced G1 accumulation, inhibited growth and promoted necrosis in combination with either 5-fluorouracil (5-FU) or vincristine (VCR), and decreased the expression of ABCC1. The dual-luciferase assay demonstrated that miR-133b directly targets ABCC1. The combination of agomiRNA-133b with chemotherapeutic drugs in vivo inhibited tumor growth induced by CRC drug-resistant cells. A xenograft from the in vivo model resulted in up-regulated levels of miR-133b and down-regulated levels of ABCC1. Therefore, miR-133b enhances the chemosensitivity of CRC cells to anti-tumor drugs by directly down-regulating ABCC1. This discovery provides a therapeutic strategy in which miR-133b is used as a potential sensitizer for drug-resistant CRC.

  5. Novel resistance functions uncovered using functional metagenomic investigations of resistance reservoirs

    Directory of Open Access Journals (Sweden)

    Erica C. Pehrsson

    2013-06-01

    Full Text Available Rates of infection with antibiotic-resistant bacteria have increased precipitously over the past several decades, with far-reaching healthcare and societal costs. Recent evidence has established a link between antibiotic resistance genes in human pathogens and those found in non-pathogenic, commensal, and environmental organisms, prompting deeper investigation of natural and human-associated reservoirs of antibiotic resistance. Functional metagenomic selections, in which shotgun-cloned DNA fragments are selected for their ability to confer survival to an indicator host, have been increasingly applied to the characterization of many antibiotic resistance reservoirs. These experiments have demonstrated that antibiotic resistance genes are highly diverse and widely distributed, many times bearing little to no similarity to known sequences. Through unbiased selections for survival to antibiotic exposure, functional metagenomics can improve annotations by reducing the discovery of false-positive resistance and by allowing for the identification of previously unrecognizable resistance genes. In this review, we summarize the novel resistance functions uncovered using functional metagenomic investigations of natural and human-impacted resistance reservoirs. Examples of novel antibiotic resistance genes include those highly divergent from known sequences, those for which sequence is entirely unable to predict resistance function, bifunctional resistance genes, and those with unconventional, atypical resistance mechanisms. Overcoming antibiotic resistance in the clinic will require a better understanding of existing resistance reservoirs and the dissemination networks that govern horizontal gene exchange, informing best practices to limit the spread of resistance-conferring genes to human pathogens.

  6. [Effective productions of plant secondary metabolites having antitumor activity by plant cell and tissue cultures].

    Science.gov (United States)

    Taniguchi, Shoko

    2005-06-01

    Methods for the effective production of plant secondary metabolites with antitumor activity using plant cell and tissue cultures were developed. The factors in tannin productivity were investigated using culture strains producing different types of hydrolyzable tannins, i.e., gallotannins (mixture of galloylglucoses), ellagi-, and dehydroellagitannins. Production of ellagi- and dehydroellagitannins was affected by the concentrations and ratio of nitrogen sources in the medium. The formation of oligomeric ellagitannins in shoots of Oenothera tetraptera was correlated with the differentiation of tissues. Cultured cells of Eriobotrya japonica producing ursane- and oleanane-type triterpenes with antitumor activities were also established.

  7. Effect of anhydrosophoradiol-3-acetate of Calotropis gigantea (Linn.) flower as antitumoric agent against Ehrlich's ascites carcinoma in mice.

    Science.gov (United States)

    Habib, Muhammad R; Karim, Muhammad R

    2013-01-01

    Over 60% of currently used anti-cancer agents are derived in one-way or another from natural sources, including plants, marine organisms and microorganisms. Calotropis gigantea (Linn.) (Family: Asclepiadaceae) is a perennial shrub and it is used as a traditional folk medicine for the treatment of various health complications. But there is no report on isolation of anticancerous chemicals from the flower of Calotropis gigantea. The objective of the present study is to explore the antitumor effect of anhydrosophoradiol-3-acetate (A3A), isolated from the flower of Calotropis gigantea (Linn.) against Ehrlich's ascites carcinoma (EAC) in Swiss albino mice. Antitumoric effect of A3A was assessed by evaluating viable tumor cell count, survival time, body weight gain due to tumor burden, hematological and biochemical (glucose, cholesterol, triglyceride, blood urea, SALP, SGPT and SGOT) parameters of EAC bearing host at doses of 10 and 20 mg/kg body weight. Treatment with A3A decreased the viable tumor cells and body weight gain thereby increasing the life span of EAC bearing mice. A3A also brought back the altered hematological (Hb, total RBC and total WBC) and biochemical parameters more or less to normal level. Results of this study conclude that in vivo the A3A was effective in inhibiting the growth of EAC with improving in cancer induced complications.

  8. Redirection to the bone marrow improves T cell persistence and antitumor functions.

    Science.gov (United States)

    Khan, Anjum B; Carpenter, Ben; Santos E Sousa, Pedro; Pospori, Constandina; Khorshed, Reema; Griffin, James; Velica, Pedro; Zech, Mathias; Ghorashian, Sara; Forrest, Calum; Thomas, Sharyn; Gonzalez Anton, Sara; Ahmadi, Maryam; Holler, Angelika; Flutter, Barry; Ramirez-Ortiz, Zaida; Means, Terry K; Bennett, Clare L; Stauss, Hans; Morris, Emma; Lo Celso, Cristina; Chakraverty, Ronjon

    2018-05-01

    A key predictor for the success of gene-modified T cell therapies for cancer is the persistence of transferred cells in the patient. The propensity of less differentiated memory T cells to expand and survive efficiently has therefore made them attractive candidates for clinical application. We hypothesized that redirecting T cells to specialized niches in the BM that support memory differentiation would confer increased therapeutic efficacy. We show that overexpression of chemokine receptor CXCR4 in CD8+ T cells (TCXCR4) enhanced their migration toward vascular-associated CXCL12+ cells in the BM and increased their local engraftment. Increased access of TCXCR4 to the BM microenvironment induced IL-15-dependent homeostatic expansion and promoted the differentiation of memory precursor-like cells with low expression of programmed death-1, resistance to apoptosis, and a heightened capacity to generate polyfunctional cytokine-producing effector cells. Following transfer to lymphoma-bearing mice, TCXCR4 showed a greater capacity for effector expansion and better tumor protection, the latter being independent of changes in trafficking to the tumor bed or local out-competition of regulatory T cells. Thus, redirected homing of T cells to the BM confers increased memory differentiation and antitumor immunity, suggesting an innovative solution to increase the persistence and functions of therapeutic T cells.

  9. Natural Variation in Elicitation of Defense-Signaling Associates to Field Resistance Against the Spot Blotch Disease in Bread Wheat (Triticum aestivum L.).

    Science.gov (United States)

    Sharma, Sandeep; Sahu, Ranabir; Navathe, Sudhir; Mishra, Vinod K; Chand, Ramesh; Singh, Pawan K; Joshi, Arun K; Pandey, Shree P

    2018-01-01

    Spot blotch, caused by the hemibiotropic fungus Bipolaris sorokiniana , is amongst the most damaging diseases of wheat. Still, natural variation in expression of biochemical traits that determine field resistance to spot blotch in wheat remain unaddressed. To understand how genotypic variations relate to metabolite profiles of the components of defense-signaling and the plant performance, as well as to discover novel sources of resistance against spot blotch, we have conducted field studies using 968 wheat genotypes at 5 geographical locations in South-Asia in 2 years. 46 genotypes were identified as resistant. Further, in independent confirmatory trials in subsequent 3 years, over 5 geographical locations, we re-characterized 55 genotypes for their resistance (above 46 along with Yangmai#6, a well characterized resistant genotype, and eight susceptible genotypes). We next determined time-dependent spot blotch-induced metabolite profiles of components of defense-signaling as well as levels of enzymatic components of defense pathway (such as salicylic acid (SA), phenolic acids, and redox components), and derived co-variation patterns with respect to resistance in these 55 genotypes. Spot blotch-induced SA accumulation was negatively correlated to disease progression. Amongst phenolic acids, syringic acid was most strongly inversely correlated to disease progression, indicating a defensive function, which was independently confirmed. Thus, exploring natural variation proved extremely useful in determining traits influencing phenotypic plasticity and adaptation to complex environments. Further, by overcoming environmental heterogeneity, our study identifies germplasm and biochemical traits that are deployable for spot blotch resistance in wheat along South-Asia.

  10. Antitumor effects of radioiodinated antisense oligonucleotide mediated by VIP receptor

    International Nuclear Information System (INIS)

    Ou Xiaohong; Tan Tianzhi; Li Yunchun; Kuang Anren

    2004-01-01

    Purpose: we had constructed a targeting delivery system based on intestinal peptide (VIP) for antisense oligonucleotide (ASON) transfer into VIP receptor-positive cells in previous study. The aims of present studies are to observe the antitumor effect of VIP-131I-ASON in HT29 human colon adenocarcinoma xenografts. Methods: A 15-met phosphorothioate ASON, which was complementary to the translation start region of the C-myc oncogene mRNA, was labeled with 131I and the labelled compound was linked to the VIP bound covalently 'to a polylysine chain so as to deliver oligonucleotide into tumor cells. Distribution experiments for evaluating the radiolabeled antisense complexe uptake in tumor tissue were performed in BALB/c nude mice bearing with HT29 tumor xenografts. Nude mice beating HT29 tumor xenografts were adminstered VIP-131I-ASON (3.7,7.4 MBq) or 131I-ASON (3.7 MBq), 131I labeled control sense and nosense DNA (3.7 MBq), or saline. Antitumor effects were assessed using endpoints of tumor growth delay. C-myc-encoded protein expression of tumor was measured by immunocytohistochemical staining. Results: Distribution experiment performed with athymic mice bearing human colon tumor xenografts revealed maximal accumulation of conjugated ASON in the tumor tissue 2 h after administration and significantly higher than that in nude mice injected unconjngated ASON [(5.89±1.03)%ID/g and(1.56±0.31)%ID/g, respectively; t=7.7954 P<0.001]. The radioratio of tumor to muscle was peaked 4h after administration. VIP-131I-ASON exhibited strong antitumor effects against HT29 xenografts, decreasing their growth rate 7-fold compare with that in saline-treated mice(tumor growth delay, 25.4±0.89 day). The antitumor effects of unconjugated 131I-ASON were much less profound than VIP-131I-ASON (tumor growth delay, 3.2±1.3 and 25.4±0.89 day, respectively; q=51.4126 P<0.01). Sense, nosense control ON with VIP carder caused no therapeutic effect. There was no progressive weight loss or

  11. Unique DNA binding mode of antitumor trinuclear tridentate platinum(II) compound

    Czech Academy of Sciences Publication Activity Database

    Olivová, R.; Kašpárková, Jana; Vrána, Oldřich; Vojtíšková, Marie; Suchánková, T.; Nováková, Olga; He, W.; Guo, Z.; Brabec, Viktor

    2011-01-01

    Roč. 8, č. 6 (2011), s. 2368-2378 ISSN 1543-8384 R&D Projects: GA MŠk(CZ) ME10066 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : platinum * antitumor * DNA Subject RIV: BO - Biophysics Impact factor: 4.782, year: 2011

  12. Natural Resistance of Eight Sapling Species to Damage by Microcerotermesgabrielis Weidner

    Directory of Open Access Journals (Sweden)

    A. Sheikhigarjan

    2017-12-01

    Full Text Available Introduction:The subterranean termites make large damage to wood and cellulosic products. They can have the destroying effects on forest plantations, agriculture crop, and urban landscaping. According to the previous studies, Microcerotermesgabrielis Weidner is the most important termite of the Alborz province belong to the family Termitidae. This species is also reported in the central, the northeastern and the southern regions of Iran. MicrocerotermesvaraminicaGhayourfar, Amitermesvilis (Hagen, A. kharaziiGhayourfar, Anacantthotermesvagan (Hagan have been also reported from Tehran province.Chemical control of termiteis the most conventional method ofcontrol. A few insecticides have acceptable termiticide effects. However more of them have negative effects on the other non-targets organisms in the environment, and may run off into groundwater. Thus we wouldconsiderthe other methods of termite control. Usage of native and natural resistant plant species can be reasonable strategy against termitesinafforestation. Plant species are food sources for termites, however, they differ in their palatabilityand can affect termite preference. There are some studies have reported differences in feeding rates and preferences of termite species amongdifferent species of woody plants. Tree Shalamzar Plantation, encompassing 54 ha in the southern Alborz mountain range have sustained termite damage since 2013. The objective of this study was to evaluate the natural resistance of eight different sapling species to termite´s damage in this region. Materials and Methods: Termites were collected from four infested locations within Shalamzar Plantation, Karaj, Iran. Infested saplings with active termite tunnels were visited and soldier termites collected and transferred to the systematics lab for species identification using a systematic key of Iranian termites. Termite infestation rates were estimatedfor each of 8 sapling species. Ten saplings of each species were

  13. Chimeric HCMV/HSV-1 and Δγ134.5 oncolytic herpes simplex virus elicit immune mediated antigliomal effect and antitumor memory

    Directory of Open Access Journals (Sweden)

    Mohammed G. Ghonime

    2018-02-01

    Full Text Available Malignant gliomas are the most common primary brain tumor and are characterized by rapid and highly invasive growth. Because of their poor prognosis, new therapeutic strategies are needed. Oncolytic virotherapy (OV is a promising strategy for treating cancer that incorporates both direct viral replication mediated and immune mediated mechanisms to kill tumor cells. C134 is a next generation Δγ134.5 oHSV-1 with improved intratumoral viral replication. It remains safe in the CNS environment by inducing early IFN signaling which restricts its replication in non-malignant cells. We sought to identify how C134 performed in an immunocompetent tumor model that restricts its replication advantage over first generation viruses. To achieve this we identified tumors that have intact IFN signaling responses that restrict C134 and first generation virus replication similarly. Our results show that both viruses elicit a T cell mediated anti-tumor effect and improved animal survival but that subtle difference exist between the viruses effect on median survival despite equivalent in vivo viral replication. To further investigate this we examined the anti-tumor activity in immunodeficient mice and in syngeneic models with re-challenge. These studies show that the T cell response is integral to C134 replication independent anti-tumor response and that OV therapy elicits a durable and circulating anti-tumor memory. The studies also show that repeated intratumoral administration can extend both OV anti-tumor effects and induce durable anti-tumor memory that is superior to tumor antigen exposure alone.

  14. Delivery of vincristine sulfate-conjugated gold nanoparticles using liposomes: a light-responsive nanocarrier with enhanced antitumor efficiency

    Directory of Open Access Journals (Sweden)

    Liu Y

    2015-04-01

    Full Text Available Ying Liu,1,* Man He,1,* Mengmeng Niu,1 Yiqing Zhao,1 Yuanzhang Zhu,1 Zhenhua Li,2 Nianping Feng1 1Department of Pharmaceutical Sciences, School of Pharmacy, Shanghai University of Traditional Chinese Medicine, Shanghai, People’s Republic of China; 2Cedars-Sinai Medical Center, Los Angeles, CA, USA *These authors contributed equally to this work Abstract: Rapid drug release at the specific site of action is still a challenge for antitumor therapy. Development of stimuli-responsive hybrid nanocarriers provides a promising strategy to enhance therapeutic effects by combining the unique features of each component. The present study explored the use of drug–gold nanoparticle conjugates incorporated into liposomes to enhance antitumor efficiency. A model drug, vincristine sulfate, was physically conjugated with gold nanoparticles and verified by UV-visible and fourier transform infrared spectroscopy, and differential scanning calorimetry. The conjugates were incorporated into liposomes by film dispersion to yield nanoparticles (113.4 nm with light-responsive release properties, as shown by in vitro release studies. Intracellular uptake and distribution was studied in HeLa cells using transmission electron microscopy and confocal laser scanning microscopy. This demonstrated liposome internalization and localization in endosomal–lysosomal vesicles. Fluorescence intensity increased in cells exposed to UV light, indicating that this stimulated intracellular drug release; this finding was confirmed by quantitative analyses using flow cytometry. Antitumor efficacy was evaluated in HeLa cells, both in culture and in implants in vivo in nude mice. HeLa cell viability assays showed that light exposure enhanced liposome cytotoxicity and induction of apoptosis. Furthermore, treatment with the prepared liposomes coupled with UV light exposure produced greater antitumor effects in nude mice and reduced side effects, as compared with free vincristine sulfate

  15. Novel T cells with improved in vivo anti-tumor activity generated by RNA electroporation

    Directory of Open Access Journals (Sweden)

    Xiaojun Liu

    2017-05-01

    Full Text Available ABSTRACT The generation of T cells with maximal anti-tumor activities will significantly impact the field of T-cell-based adoptive immunotherapy. In this report, we found that OKT3/IL-2-stimulated T cells were phenotypically more heterogeneous, with enhanced anti-tumor activity in vitro and when locally administered in a solid tumor mouse model. To further improve the OKT3/IL-2-based T cell manufacturing procedure, we developed a novel T cell stimulation and expansion method in which peripheral blood mononuclear cells were electroporated with mRNA encoding a chimeric membrane protein consisting of a single-chain variable fragment against CD3 and the intracellular domains of CD28 and 4-1BB (OKT3-28BB. The expanded T cells were phenotypically and functionally similar to T cells expanded by OKT3/IL-2. Moreover, co-electroporation of CD86 and 4-1BBL could further change the phenotype and enhance the in vivo anti-tumor activity. Although T cells expanded by the co-electroporation of OKT3-28BB with CD86 and 4-1BBL showed an increased central memory phenotype, the T cells still maintained tumor lytic activities as potent as those of OKT3/IL-2 or OKT3-28BB-stimulated T cells. In different tumor mouse models, T cells expanded by OKT3-28BB RNA electroporation showed anti-tumor activities superior to those of OKT3/IL-2 T cells. Hence, T cells with both a less differentiated phenotype and potent tumor killing ability can be generated by RNA electroporation, and this T cell manufacturing procedure can be further optimized by simply co-delivering other splices of RNA, thus providing a simple and cost-effective method for generating high-quality T cells for adoptive immunotherapy.

  16. Novel Therapeutic Strategies for Solid Tumor Based on Body's Intrinsic Antitumor Immune System.

    Science.gov (United States)

    Duan, Haifeng

    2018-05-22

    The accumulation of mutated somatic cells due to the incompetency of body's immune system may lead to tumor onset. Therefore, enhancing the ability of the system to eliminate such cells should be the core of tumor therapy. The intrinsic antitumor immunity is triggered by tumor-specific antigens (TSA) or TSA-sensitized dendritic cells (DC). Once initiated, specific anti-tumor antibodies are produced and tumor-specific killer immune cells, including cytotoxic T lymphocytes (CTL), NK cells, and macrophages, are raised or induced. Several strategies may enhance antitumor action of immune system, such as supplying tumor-targeted antibody, activating T cells, enhancing the activity and tumor recognition of NK cells, promoting tumor-targeted phagocytosis of macrophages, and eliminating the immunosuppressive myeloid-derived suppressor cells (MDSCs) and Treg cells. Apart from the immune system, the removal of tumor burden still needs to be assisted by drugs, surgery or radiation. And the body's internal environment and tumor microenvironment should be improved to recover immune cell function and prevent tumor growth. Multiple microenvironment modulatory therapies may be applied, including addressing hypoxia and oxidative stress, correcting metabolic disorders, and controlling chronic inflammation. Finally, to cure tumor and prevent tumor recurrence, repairing or supporting therapy that consist of tissue repair and nutritional supplement should be applied properly. © 2018 The Author(s). Published by S. Karger AG, Basel.

  17. Antioxidants Impair Anti-Tumoral Effects of Vorinostat, but Not Anti-Neoplastic Effects of Vorinostat and Caspase-8 Downregulation

    OpenAIRE

    Bergadà, Laura; Yeramian, Andree; Sorolla, Annabel; Matias-Guiu, Xavier; Dolcet, Xavier

    2014-01-01

    We have recently demonstrated that histone deacetylase inhibitor, Vorinostat, applied as a single therapy or in combination with caspase-8 downregulation exhibits high anti-tumoral activity on endometrial carcinoma cell lines. In the present study, we have assessed the signalling processes underlying anti-tumoral effects of Vorinostat. Increasing evidence suggests that reactive oxygen species are responsible for histone deacetylase inhibitor-induced cell killing. We have found that Vorinostat...

  18. Electrical resistivity measurements to predict abrasion resistance of ...

    Indian Academy of Sciences (India)

    WINTEC

    increasing expansion of highway and other construction works and decreasing natural aggregate resources in the world, the demand for crushed stone aggregates has in- creased from day-to-day. One of the important properties of rock aggregates is abrasion resistance. The abrasion resistance of aggregates is generally ...

  19. The MET/AXL/FGFR Inhibitor S49076 Impairs Aurora B Activity and Improves the Antitumor Efficacy of Radiotherapy.

    Science.gov (United States)

    Clémenson, Céline; Chargari, Cyrus; Liu, Winchygn; Mondini, Michele; Ferté, Charles; Burbridge, Mike F; Cattan, Valérie; Jacquet-Bescond, Anne; Deutsch, Eric

    2017-10-01

    Several therapeutic agents targeting HGF/MET signaling are under clinical development as single agents or in combination, notably with anti-EGFR therapies in non-small cell lung cancer (NSCLC). However, despite increasing data supporting a link between MET, irradiation, and cancer progression, no data regarding the combination of MET-targeting agents and radiotherapy are available from the clinic. S49076 is an oral ATP-competitive inhibitor of MET, AXL, and FGFR1-3 receptors that is currently in phase I/II clinical trials in combination with gefitinib in NSCLC patients whose tumors show resistance to EGFR inhibitors. Here, we studied the impact of S49076 on MET signaling, cell proliferation, and clonogenic survival in MET-dependent (GTL16 and U87-MG) and MET-independent (H441, H460, and A549) cells. Our data show that S49076 exerts its cytotoxic activity at low doses on MET-dependent cells through MET inhibition, whereas it inhibits growth of MET-independent cells at higher but clinically relevant doses by targeting Aurora B. Furthermore, we found that S49076 improves the antitumor efficacy of radiotherapy in both MET-dependent and MET-independent cell lines in vitro and in subcutaneous and orthotopic tumor models in vivo In conclusion, our study demonstrates that S49076 has dual antitumor activity and can be used in combination with radiotherapy for the treatment of both MET-dependent and MET-independent tumors. These results support the evaluation of combined treatment of S49076 with radiation in clinical trials without patient selection based on the tumor MET dependency status. Mol Cancer Ther; 16(10); 2107-19. ©2017 AACR . ©2017 American Association for Cancer Research.

  20. Natural Products from Mangrove Actinomycetes

    Science.gov (United States)

    Xu, Dong-Bo; Ye, Wan-Wan; Han, Ying; Deng, Zi-Xin; Hong, Kui

    2014-01-01

    Mangroves are woody plants located in tropical and subtropical intertidal coastal regions. The mangrove ecosystem is becoming a hot spot for natural product discovery and bioactivity survey. Diverse mangrove actinomycetes as promising and productive sources are worth being explored and uncovered. At the time of writing, we report 73 novel compounds and 49 known compounds isolated from mangrove actinomycetes including alkaloids, benzene derivatives, cyclopentenone derivatives, dilactones, macrolides, 2-pyranones and sesquiterpenes. Attractive structures such as salinosporamides, xiamycins and novel indolocarbazoles are highlighted. Many exciting compounds have been proven as potential new antibiotics, antitumor and antiviral agents, anti-fibrotic agents and antioxidants. Furthermore, some of their biosynthetic pathways have also been revealed. This review is an attempt to consolidate and summarize the past and the latest studies on mangrove actinomycetes natural product discovery and to draw attention to their immense potential as novel and bioactive compounds for marine drugs discovery. PMID:24798926

  1. THE PHENOMENON OF RESISTANCE TO CHANGE: THE NATURE, TYPES AND FORMS

    OpenAIRE

    N. M. Kobzeva

    2013-01-01

    The article describes the essence of the phenomenon of resistance to change. The au-thor's definition of «resistance to change» is given. The existing approaches to the study of resistance to change are analyzed. Causes of resistance to change in organiza-tions are described. Generalizing classification of resistance to change is proposed.

  2. Naturally occurring hepatitis C virus protease inhibitors resistance-associated mutations among chronic hepatitis C genotype 1b patients with or without HIV co-infection.

    Science.gov (United States)

    Cao, Ying; Zhang, Yu; Bao, Yi; Zhang, Renwen; Zhang, Xiaxia; Xia, Wei; Wu, Hao; Xu, Xiaoyuan

    2016-05-01

    The aim of this study was to measure the frequency of natural mutations in hepatitis C virus (HCV) mono-infected and HIV/HCV co-infected protease inhibitor (PI)-naive patients. Population sequence of the non-structural (NS)3 protease gene was evaluated in 90 HCV mono-infected and 96 HIV/HCV co-infected PI treatment-naive patients. The natural prevalence of PI resistance mutations in both groups was compared. Complete HCV genotype 1b NS3 sequence information was obtained for 152 (81.72%) samples. Seven sequences (8.33%) of the 84 HCV mono-infected patients and 21 sequences (30.88%) of the 68 HIV/HCV co-infected patients showed amino acid substitutions associated with HCV PI resistance. There was a significant difference in the natural prevalence of PI resistance mutations between these two groups (P = 0.000). The mutations T54S, R117H and N174F were observed in 1.19%, 5.95% and 1.19% of HCV mono-infected patients. The mutations F43S, T54S, Q80K/R, R155K, A156G/V, D168A/E/G and V170A were found in 1.47%, 4.41%, 1.47%/1.47%, 2.94%, 23.53%/1.47%, 1.47%/1.47%/1.47% and 1.47% of HIV/HCV co-infected patients, respectively. In addition, the combination mutations in the NS3 region were detected only in HIV/HCV genotype 1b co-infected patients. Naturally occurring HCV PI resistance mutations existed in HCV mono-infected and HIV/HCV co-infected genotype 1b PI-naive patients. HIV co-infection was associated with a greater frequency of PI resistance mutations. The impact of HIV infection on baseline HCV PI resistance mutations and treatment outcome in chronic hepatitis C (CHC) patients should be further analyzed. © 2015 The Japan Society of Hepatology.

  3. Increasing antitumor effects of chemoradiotherapy by drug efflux inhibition with encapsulated anti-RLIP-76

    International Nuclear Information System (INIS)

    Harada, Satoshi; Ehara, Shigeru; Ishii, Keizo

    2011-01-01

    Microencapsulated anti-RLIP76 was tested in vivo using C3He/J mice to determine the increasing of antitumor effects by chemotherapeutic agent efflux inhibition during chemoradiotherapy. Microcapsules were produced by spraying a mixture of 3.0% hyaluronic acid, 2.0% alginate, 3.0% H 2 O 2 , and 0.3 mmol carboplatin onto a mixture of 0.3 mol FeCl 2 and 0.15 mol CaCl 2 . Microcapsules were subcutaneously injected into MM46 tumors previously inoculated into the left hind legs of C3He/J mice. Subsequent radiotherapy consisted of tumor irradiation with 10 Gy or 20 Gy 60 Co. The antitumor effects of microcapsules were tested by measuring tumor size and monitoring tumor growth. Three types of adverse effects were considered: fuzzy hair, loss of body weight, and mortality. Carboplatin levels were monitored using particle-induced X-ray emission (PIXE) and a micro-PIXE camera. Anti-RLIP76 inhibited the efflux of carboplatin from tumor tissue, which led to an increase in the concentration of carboplatin. Higher carboplatin concentration significantly increased the combined antitumor effect of radiation and chemotherapy. A significant decrease in adverse effects was also observed with microencapsulated anti-RLIP76. (author)

  4. Effect of Paris saponin on antitumor and immune function in U14 ...

    African Journals Online (AJOL)

    bearing mice, and reduced the serum IL-4 level. The Paris saponin can inhibit U14 cell growth and prolong survival time of mice; it is speculated that the Paris saponin may express its anti-tumor activity by improving the body's immune system.

  5. Risk of Lymphoma in Patients With Inflammatory Bowel Disease Treated With Anti-Tumor Necrosis Factor Alpha Agents: A Systematic Review and Meta-analysis.

    Science.gov (United States)

    Yang, Chen; Huang, Junlin; Huang, Xiaowen; Huang, Shaozhuo; Cheng, Jiaxin; Liao, Weixin; Chen, Xuewen; Wang, Xueyi; Dai, Shixue

    2018-05-12

    The association between anti-tumor necrosis factor alpha agents and the risk of lymphoma in patients with inflammatory bowel disease has already been sufficiently reported. However, the results of these studies are inconsistent. Hence, this analysis was conducted to investigate whether anti-tumor necrosis factor alpha agents can increase the risk of lymphoma in inflammatory bowel disease patients. MEDLINE, EMBASE and the Cochrane Library were searched to identify relevant studies which evaluated the risk of lymphoma in inflammatory bowel disease patients treated with anti-tumor necrosis factor alpha agents. A random-effects meta-analysis was performed to calculate the pooled incidence rate ratios as well as risk ratios. Twelve studies comprising 285811 participants were included. The result showed that there was no significantly increased risk of lymphoma between anti-tumor necrosis factor alpha agents exposed and anti-tumor necrosis factor alpha agents unexposed groups (random effects: incidence rate ratio [IRR], 1.43 95%CI, 0.91-2.25, p= 0.116; random effects: risk ratio [RR], 0.83 95%CI, 0.47-1.48, p=0.534). However, monotherapy of anti-tumor necrosis factor alpha agents (random effects: IRR=1.65, 95%CI, 1.16-2.35; p=0.006; random effects: RR=1.00, 95%CI, 0.39-2.59; p=0.996) or combination therapy (random effects: IRR=3.36, 95%CI, 2.23-5.05; ptumor necrosis factor alpha agents in patients with inflammatory bowel disease is not associated with a higher risk of lymphoma. Combination therapy and anti-tumor necrosis factor alpha agents monotherapy can significantly increase the risk of lymphoma in patients with inflammatory bowel disease.

  6. Antioxidants impair anti-tumoral effects of Vorinostat, but not anti-neoplastic effects of Vorinostat and caspase-8 downregulation.

    Science.gov (United States)

    Bergadà, Laura; Yeramian, Andree; Sorolla, Annabel; Matias-Guiu, Xavier; Dolcet, Xavier

    2014-01-01

    We have recently demonstrated that histone deacetylase inhibitor, Vorinostat, applied as a single therapy or in combination with caspase-8 downregulation exhibits high anti-tumoral activity on endometrial carcinoma cell lines. In the present study, we have assessed the signalling processes underlying anti-tumoral effects of Vorinostat. Increasing evidence suggests that reactive oxygen species are responsible for histone deacetylase inhibitor-induced cell killing. We have found that Vorinostat induces formation of reactive oxygen species and DNA damage. To investigate the role of oxidative stress as anti-neoplastic mechanism, we have evaluated the effects of different antioxidants (Bha, Nac and Tiron) on endometrial carcinoma cell line Ishikawa treated with Vorinostat. We show that Bha, Nac and Tiron markedly inhibited the cytotoxic effects of Vorinostat, increasing cell viability in vitro. We found that all three antioxidants did not inhibited accumulation of acetyl Histone H4, so that antioxidants did not inhibit Vorinostat activity. Finally, we have evaluated the effects of antioxidants on anti-tumoral activity of Vorinostat as monotherapy or in combination with caspase-8 downregulation in vivo. Interestingly, antioxidants blocked the reduction of tumour growth caused by Vorinostat, but they were unable to inhibit anti-tumoral activity of Vorinostat plus caspase-8 inhibition.

  7. Antitumor mechanisms of metformin: Signaling, metabolism, immunity and beyond

    OpenAIRE

    Duque, Jorge Eduardo; Grupo de Terapia Celular y Molecular, Pontificia Universidad Javeriana, Bogotá D.C.; López, Catalina; Grupo de Investigación en Terapia Regenerativa, Universidad de Caldas, Manizales; Cruz, Nataly; Grupo de Terapia Celular y Molecular, Pontificia Universidad Javeriana, Bogotá D.C.; Samudio, Ismael; Grupo de Terapia Celular y Molecular, Pontificia Universidad Javeriana, Bogotá D.C.

    2010-01-01

    Metformin is a synthetic biguanide first described in the 1920´s as a side product of the synthesis of N,N-dimethylguanidine. Like other related biguanides, metformin displays antihyperglycemic properties, and has become the most widely prescribed oral antidiabetic medicine around the world. Intriguing recent evidence suggests that metformin has chemopreventive and direct antitumor properties, and several ongoing clinical studies around the world are using this agent alone or in combi...

  8. Antitumoral action of interferons and interleukins in combination with radiotherapy. Pt. I. Immunologic basis

    International Nuclear Information System (INIS)

    Herskind, C.; Fleckenstein, K.; Wenz, F.; Lohr, F.; Lohr, J.; Li Chuan-Yuan

    2004-01-01

    Method: the cellular immune response toward tumor cells is reviewed. The role of cytokines in antigen presentation and activation of effector cells and their interactions with radiation are described. Preclinical strategies of the antitumor action of cytokines are presented and discussed based on the induction of IFN-γ by IL-12. Results: recent advances in immunology have demonstrated the importance of local interactions between antigen-presenting cells (APC) and effector cells such as natural killer (NK) cells and T-lymphocytes for an effective immune reaction against tumors. Interferons stimulate such interactions, while IL-2 plays a central role in the activation of NK cells and T-lymphocytes. The interactions between APC and effector cells are suppressed by many tumors but can be stimulated by irradiation. Since systemic application of interferons is quite toxic, present strategies aim at local expression, e.g., the induction of IFN-γ expression in Th1 cells by IL-12. (orig.) [de

  9. A review of electroporation-based antitumor skin therapies and investigation of betulinic acid-loaded ointment.

    Science.gov (United States)

    Bakonyi, Monika; Berko, Szilvia; Eros, Gabor; Varju, Gabor; Dehelean, Cristina; Szucs, Maria Budai; Csanyi, Erzsebet

    2017-11-13

    Electrochemotherapy is a novel treatment for cutaneous and subcutaneous tumors utilizing the combination of electroporation and chemotherapeutic agents. Since tumors have an increasing incidence nowadays as a result of environmental and genetic factors, electrochemotherapy could be a promising treatment for cancer patients. The aim of this article is to summarize the novel knowledge about the use of electroporation for antitumor treatments and to present a new application of electrochemotherapy with a well-known plant derived antitumor drug betulinic acid. For the review we have searched the databases of scientific and medical research to collect the available publications about the use of electrochemotherapy in the treatment of various types of cancer. By the utilization of the available knowledge, we investigated the effect of electroporation on the penetration of a topically applied betulinic acid formulation into the skin by ex vivo Raman spectroscopy on hairless mouse skin Results: Raman measurements have demonstrated that the penetration depth of betulinic acid can be remarkably ameliorated by the use of electroporation, so this protocol can be a possibility for the treatment of deeper localized cancer nodules. Furthermore, it proved the influence of various treatment times, since they caused different spatial distributions of the drug in the skin. The review demonstrates that electrochemotherapy is a promising tool to treat different kinds of tumors with high efficiency and with only a few moderate adverse effects. Moreover, it presents a non-invasive method to enhance the penetration of antitumor agents, which can offer novel prospects for antitumor therapies. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  10. How does ionizing irradiation contribute to the induction of anti-tumor immunity?

    Directory of Open Access Journals (Sweden)

    Yvonne eRubner

    2012-07-01

    Full Text Available Radiotherapy (RT with ionizing irradiation is commonly used to locally attack tumors. It induces a stop of cancer cell proliferation and finally leads to tumor cell death. During the last years it has become more and more evident that besides a timely and locally restricted radiation-induced immune suppression, a specific immune activation against the tumor and its metastases is achievable by rendering the tumor cells visible for immune attack. The immune system is involved in tumor control and we here outline how RT induces anti-inflammation when applied in low doses and contributes in higher doses to the induction of anti-tumor immunity. We especially focus on how local irradiation induces abscopal effects. The latter are partly mediated by a systemic activation of the immune system against the individual tumor cells. Dendritic cells are the key players in the initiation and regulation of adaptive anti-tumor immune responses. They have to take up tumor antigens and consecutively present tumor peptides in the presence of appropriate co-stimulation. We review how combinations of RT with further immune stimulators such as AnnexinA5 and hyperthermia foster the dendritic cell-mediated induction of anti-tumor immune responses and present reasonable combination schemes of standard tumor therapies with immune therapies. It can be concluded that RT leads to targeted killing of the tumor cells and additionally induces non-targeted systemic immune effects. Multimodal tumor treatments should therefore tend to induce immunogenic tumor cell death forms within a tumor microenvironment that stimulates immune cells.

  11. How Does Ionizing Irradiation Contribute to the Induction of Anti-Tumor Immunity?

    International Nuclear Information System (INIS)

    Rubner, Yvonne; Wunderlich, Roland; Rühle, Paul-Friedrich; Kulzer, Lorenz; Werthmöller, Nina; Frey, Benjamin; Weiss, Eva-Maria; Keilholz, Ludwig; Fietkau, Rainer; Gaipl, Udo S.

    2012-01-01

    Radiotherapy (RT) with ionizing irradiation is commonly used to locally attack tumors. It induces a stop of cancer cell proliferation and finally leads to tumor cell death. During the last years it has become more and more evident that besides a timely and locally restricted radiation-induced immune suppression, a specific immune activation against the tumor and its metastases is achievable by rendering the tumor cells visible for immune attack. The immune system is involved in tumor control and we here outline how RT induces anti-inflammation when applied in low doses and contributes in higher doses to the induction of anti-tumor immunity. We especially focus on how local irradiation induces abscopal effects. The latter are partly mediated by a systemic activation of the immune system against the individual tumor cells. Dendritic cells are the key players in the initiation and regulation of adaptive anti-tumor immune responses. They have to take up tumor antigens and consecutively present tumor peptides in the presence of appropriate co-stimulation. We review how combinations of RT with further immune stimulators such as AnnexinA5 and hyperthermia foster the dendritic cell-mediated induction of anti-tumor immune responses and present reasonable combination schemes of standard tumor therapies with immune therapies. It can be concluded that RT leads to targeted killing of the tumor cells and additionally induces non-targeted systemic immune effects. Multimodal tumor treatments should therefore tend to induce immunogenic tumor cell death forms within a tumor microenvironment that stimulates immune cells.

  12. Antitumor Effect of KX-01 through Inhibiting Src Family Kinases and Mitosis.

    Science.gov (United States)

    Kim, Seongyeong; Min, Ahrum; Lee, Kyung-Hun; Yang, Yaewon; Kim, Tae-Yong; Lim, Jee Min; Park, So Jung; Nam, Hyun-Jin; Kim, Jung Eun; Song, Sang-Hyun; Han, Sae-Won; Oh, Do-Youn; Kim, Jee Hyun; Kim, Tae-You; Hangauer, David; Lau, Johnson Yiu-Nam; Im, Kyongok; Lee, Dong Soon; Bang, Yung-Jue; Im, Seock-Ah

    2017-07-01

    KX-01 is a novel dual inhibitor of Src and tubulin. Unlike previous Src inhibitors that failed to show clinical benefit during treatment of breast cancer, KX-01 can potentially overcome the therapeutic limitations of current Src inhibitors through inhibition of both Src and tubulin. The present study further evaluates the activity and mechanism of KX-01 in vitro and in vivo . The antitumor effect of KX-01 in triple negative breast cancer (TNBC) cell lines was determined by MTT assay. Wound healing and immunofluorescence assays were performed to evaluate the action mechanisms of KX-01. Changes in the cell cycle and molecular changes induced by KX-01 were also evaluated. A MDA-MB-231 mouse xenograft model was used to demonstrate the in vivo effects. KX-01 effectively inhibited the growth of breast cancer cell lines. The expression of phospho-Src and proliferative-signaling molecules were down-regulated in KX-01-sensitive TNBC cell lines. In addition, migration inhibition was observed by wound healing assay. KX-01-induced G2/M cell cycle arrest and increased the aneuploid cell population in KX-01-sensitive cell lines. Multi-nucleated cells were significantly increased after KX-01 treatment. Furthermore, KX-01 effectively delayed tumor growth in a MDA-MB-231 mouse xenograft model. KX-01 effectively inhibited cell growth and migration of TNBC cells. Moreover, this study demonstrated that KX-01 showed antitumor effects through the inhibition of Src signaling and the induction of mitotic catastrophe. The antitumor effects of KX-01 were also demonstrated in vivo using a mouse xenograft model.

  13. Induction of mitophagy-mediated antitumor activity with folate-appended methyl-β-cyclodextrin.

    Science.gov (United States)

    Kameyama, Kazuhisa; Motoyama, Keiichi; Tanaka, Nao; Yamashita, Yuki; Higashi, Taishi; Arima, Hidetoshi

    2017-01-01

    Mitophagy is the specific autophagic elimination system of mitochondria, which regulates cellular survival via the removal of damaged mitochondria. Recently, we revealed that folate-appended methyl-β-cyclodextrin (FA-M-β-CyD) provides selective antitumor activity in folate receptor-α (FR-α)-expressing cells by the induction of autophagy. In this study, to gain insight into the detailed mechanism of this antitumor activity, we focused on the induction of mitophagy by the treatment of FR-α-expressing tumor cells with FA-M-β-CyD. In contrast to methyl-β-cyclodextrin, FA-M-β-CyD entered KB cells, human epithelial cells from a fatal cervical carcinoma (FR-α (+)) through FR-α-mediated endocytosis. The transmembrane potential of isolated mitochondria after treatment with FA-M-β-CyD was significantly elevated. In addition, FA-M-β-CyD lowered adenosine triphosphate (ATP) production and promoted reactive oxygen species production in KB cells (FR-α (+)). Importantly, FA-M-β-CyD enhanced light chain 3 (LC3) conversion (LC3-I to LC3-II) in KB cells (FR-α (+)) and induced PTEN-induced putative kinase 1 (PINK1) protein expression, which is involved in the induction of mitophagy. Furthermore, FA-M-β-CyD had potent antitumor activity in BALB/c nu/nu mice xenografted with KB cells (FR-α (+)) without any significant side effects. Taken together, these findings demonstrate that the autophagic cell death elicited by FA-M-β-CyD could be associated with mitophagy induced by an impaired mitochondrial function.

  14. Natural variation in partial resistance to Pseudomonas syringae is controlled by two major QTLs in Arabidopsis thaliana.

    Directory of Open Access Journals (Sweden)

    Laure Perchepied

    Full Text Available BACKGROUND: Low-level, partial resistance is pre-eminent in natural populations, however, the mechanisms underlying this form of resistance are still poorly understood. METHODOLOGY/PRINCIPAL FINDINGS: In the present study, we used the model pathosystem Pseudomonas syringae pv. tomato DC3000 (Pst - Arabidopsis thaliana to study the genetic basis of this form of resistance. Phenotypic analysis of a set of Arabidopsis accessions, based on evaluation of in planta pathogen growth revealed extensive quantitative variation for partial resistance to Pst. It allowed choosing a recombinant inbred line (RIL population derived from a cross between the accessions Bayreuth and Shahdara for quantitative genetic analysis. Experiments performed under two different environmental conditions led to the detection of two major and two minor quantitative trait loci (QTLs governing partial resistance to Pst and called PRP-Ps1 to PRP-Ps4. The two major QTLs, PRP-Ps1 and PRP-Ps2, were confirmed in near isogenic lines (NILs, following the heterogeneous inbred families (HIFs strategy. Analysis of marker gene expression using these HIFs indicated a negative correlation between the induced amount of transcripts of SA-dependent genes PR1, ICS and PR5, and the in planta bacterial growth in the HIF segregating at PRP-Ps2 locus, suggesting an implication of PRP-Ps2 in the activation of SA dependent responses. CONCLUSIONS/SIGNIFICANCE: These results show that variation in partial resistance to Pst in Arabidopsis is governed by relatively few loci, and the validation of two major loci opens the way for their fine mapping and their cloning, which will improve our understanding of the molecular mechanisms underlying partial resistance.

  15. Increased nature relatedness and decreased authoritarian political views after psilocybin for treatment-resistant depression.

    Science.gov (United States)

    Lyons, Taylor; Carhart-Harris, Robin L

    2018-01-01

    Previous research suggests that classical psychedelic compounds can induce lasting changes in personality traits, attitudes and beliefs in both healthy subjects and patient populations. Here we sought to investigate the effects of psilocybin on nature relatedness and libertarian-authoritarian political perspective in patients with treatment-resistant depression (TRD). This open-label pilot study with a mixed-model design studied the effects of psilocybin on measures of nature relatedness and libertarian-authoritarian political perspective in patients with moderate to severe TRD ( n=7) versus age-matched non-treated healthy control subjects ( n=7). Psilocybin was administered in two oral dosing sessions (10 mg and 25 mg) 1 week apart. Main outcome measures were collected 1 week and 7-12 months after the second dosing session. Nature relatedness and libertarian-authoritarian political perspective were assessed using the Nature Relatedness Scale (NR-6) and Political Perspective Questionnaire (PPQ-5), respectively. Nature relatedness significantly increased ( t(6)=-4.242, p=0.003) and authoritarianism significantly decreased ( t(6)=2.120, p=0.039) for the patients 1 week after the dosing sessions. At 7-12 months post-dosing, nature relatedness remained significantly increased ( t(5)=-2.707, p=0.021) and authoritarianism remained decreased at trend level ( t(5)=-1.811, p=0.065). No differences were found on either measure for the non-treated healthy control subjects. This pilot study suggests that psilocybin with psychological support might produce lasting changes in attitudes and beliefs. Although it would be premature to infer causality from this small study, the possibility of drug-induced changes in belief systems seems sufficiently intriguing and timely to deserve further investigation.

  16. Natural killer cells inhibit oxaliplatin-resistant colorectal cancer by repressing WBSCR22 via upregulating microRNA-146b-5p.

    Science.gov (United States)

    Zhao, Haiyan; Su, Wuyun; Kang, Qingmei; Xing, Ze; Lin, Xue; Wu, Zhongjun

    2018-01-01

    Natural killer (NK) cells have exhibited promising efficacy in inhibiting cancer growth. We aimed to explorer the effect of NK cells on oxaliplatin-resistant colorectal cancer and the underlying molecular mechanism. Oxaliplatin-resistant colorectal cancer cell lines were co-cultured with NK cells to evaluate the effect on viability, proliferation, migration and invasion in vitro . Oxaliplatin-resistant colorectal cancer cells were also co-injected with NK cells into mice to establish xenograft tumor model, to assess the in vivo effect of NK cells on tumorigenesis of the oxaliplatin-resistant colorectal cancer cells. Expression of WBSCR22 gene was assessed in the oxaliplatin-resistant colorectal cancer cells following NK cell treatment to elucidate the mechanism. NK cell treatment significantly reduces growth of oxaliplatin-resistant colorectal cancer cells both in vitro and in vivo , as well as reduced WBSCR22 expression. MicroRNAs potentially targeting WBSCR22 were analyzed, and microRNA-146b-5p was found to be significantly upregulated following NK cell treatment. MicroRNA-146b-5p directly targeted WBSCR22 mRNA 3'-UTR to inhibit its expression, which was required for NK cell-induced inhibition of oxaliplatin-resistant colorectal cancer cell lines. NK cells inhibit oxaliplatin-resistant colorectal cancer by repressing WBSCR22 via upregulating microRNA-146b-5p, both of which could serve as candidates for targeted therapy against oxaliplatin-resistant colorectal cancer.

  17. Improved Antitumor Efficacy and Pharmacokinetics of Bufalin via PEGylated Liposomes

    Science.gov (United States)

    Yuan, Jiani; Zhou, Xuanxuan; Cao, Wei; Bi, Linlin; Zhang, Yifang; Yang, Qian; Wang, Siwang

    2017-11-01

    Bufalin was reported to show strong pharmacological effects including cardiotonic, antiviral, immune-regulation, and especially antitumor effects. The objective of this study was to determine the characterization, antitumor efficacy, and pharmacokinetics of bufalin-loaded PEGylated liposomes compared with bufalin entity, which were prepared by FDA-approved pharmaceutical excipients. Bufalin-loaded PEGylated liposomes and bufalin-loaded liposomes were prepared reproducibly with homogeneous particle size by the combination of thin film evaporation method and high-pressure homogenization method. Their mean particle sizes were 127.6 and 155.0 nm, mean zeta potentials were 2.24 and - 18.5 mV, and entrapment efficiencies were 76.31 and 78.40%, respectively. In vitro release profile revealed that the release of bufalin in bufalin-loaded PEGylated liposomes was slower than that in bufalin-loaded liposomes. The cytotoxicity of blank liposomes has been found within acceptable range, whereas bufalin-loaded PEGylated liposomes showed enhanced cytotoxicity to U251 cells compared with bufalin entity. In vivo pharmacokinetics indicated that bufalin-loaded PEGylated liposomes could extend or eliminate the half-life time of bufalin in plasma in rats. The results suggested that bufalin-loaded PEGylated liposomes improved the solubility and increased the drug concentration in plasma.

  18. Role of a bacillus Calmette-Guérin fibronectin attachment protein in BCG-induced antitumor activity.

    Science.gov (United States)

    Zhao, W; Schorey, J S; Bong-Mastek, M; Ritchey, J; Brown, E J; Ratliff, T L

    2000-04-01

    Intravesical Mycobacterium bovis bacillus Calmette-Gu*erin (BCG) is the treatment of choice for superficial bladder cancer. Previous studies showed that attachment of BCG to fibronectin within the bladder was necessary for mediation of the antitumor response. Further studies identified a bacterial receptor, fibronectin attachment protein (FAP), as an important mediator of BCG attachment to fibronectin. In vitro studies showed that a stable BCG/fibronectin interaction was dependent on FAP binding to fibronectin; however, no role for FAP in the attachment of BCG in vivo has been characterized. We now report the cloning of the M. bovis BCG FAP (FAP-B) and demonstrate an important role for FAP in the in vivo attachment of BCG to the bladder wall and in the induction of BCG-mediated antitumor activity. The predicted amino acid sequence for FAP-B shows 61% and 71% homology, respectively, with Mycobacterium avium FAP (FAP-A) and Mycobacterium leprae FAP (FAP-L). Rabbit polyclonal antibodies against Mycobacterium vaccae FAP (FAP-V) reacted with all 3 recombinant FAP proteins on Western blots. Functional studies show FAP-B to bind fibronectin via the highly conserved attachment regions previously identified for FAP-A and FAP-L and also to competitively inhibit attachment of BCG to matrix fibronectin. In vivo studies show FAP to be a necessary protein for the stable attachment of BCG to the bladder wall. Moreover, stable binding of BCG via FAP was shown to be necessary for the expression of BCG-induced antitumor activity. Our results demonstrate a biological role for FAP in the mediation of BCG-induced antitumor activity.

  19. Antitumor function and mechanism of phycoerythrin from Porphyra haitanensis

    Directory of Open Access Journals (Sweden)

    Qunwen Pan

    2013-01-01

    Full Text Available The anti-tumor effect of R-Phycoerythrin (R-PE from Porphyra haitanensis was studied using cell line HeLa as an in vitro model and Sarcoma-180 (S180 tumor-bearing mice as an in vivo model. The results showed that the combination treatment of R-PE and photodynamic therapy PDT significantly inhibited the growth of HeLa cells up to 81.5%, with a fair dose-effect relationship, but did not inhibit endothelial cells. The annexin v-fitc/PI fluorescence staining experiments demonstrated that at doses between 0~60µg/mL, apoptosis cells and later stage apoptosis cells or necrosis cells increased significantly as the R-PE dosage increased. DNA electrophoresis showed that after R-PE+PDT treatment of HeLa cells for 24 hours, a light "smear" band between 100~400bp appeared to indicate the degradation of genomic DNA. The QRT-PCR results showed that R-PE+PDT treatment increased caspase-3 and caspase-10 gene expression and decreased the Bcl-2 gene expression level significantly as the R-PE dose increased, implying that R-PE promoted HeLa cell apoptosis. Compared with untreated S180 tumor-bearing mice, R-PE injection significantly inhibited the growth of S180 in tumor-bearing mice up to 41.3% at a dose of 300mg-kg-1. Simultaneously, the significant increase of superoxide dismutase (SOD activity in serum (p < 0.01 and the decrease of the malondialdehyde (MDA level in liver suggests that R-PE improved the anti-oxidant ability of the S180 tumor-bearing mice, which may related to its antitumor effect. In addition, the R-PE caused a significant increase (p < 0.05 in the spleen index and thymus index, and a significant increase (p < 0.01 in lymphocyte proliferation, NK cell kill activity and the TNF-α level in the serum of S180 tumor-bearing mice. These results strongly suggest that the antitumor effect of R-PE from Porphyra haitanensis functioned by increasing the immunity and antioxidant ability of S180 tumor-bearing mice, promoting apoptosis by increasing protease

  20. Selected anti-tumor vaccines merit a place in multimodal tumor therapies

    Energy Technology Data Exchange (ETDEWEB)

    Weiss, Eva-Maria; Wunderlich, Roland [Department of Radiation Oncology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen (Germany); Ebel, Nina [Department of Process Technology and Machinery, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen (Germany); Rubner, Yvonne [Department of Radiation Oncology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen (Germany); Schlücker, Eberhard [Department of Process Technology and Machinery, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen (Germany); Meyer-Pittroff, Roland [Competence Pool Weihenstephan, Technische Universität München, Freising (Germany); Ott, Oliver J.; Fietkau, Rainer; Gaipl, Udo S.; Frey, Benjamin, E-mail: benjamin.frey@uk-erlangen.de [Department of Radiation Oncology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen (Germany)

    2012-10-09

    Multimodal approaches are nowadays successfully applied in cancer therapy. Primary locally acting therapies such as radiotherapy (RT) and surgery are combined with systemic administration of chemotherapeutics. Nevertheless, the therapy of cancer is still a big challenge in medicine. The treatments often fail to induce long-lasting anti-tumor responses. Tumor recurrences and metastases result. Immunotherapies are therefore ideal adjuncts to standard tumor therapies since they aim to activate the patient's immune system against malignant cells even outside the primary treatment areas (abscopal effects). Especially cancer vaccines may have the potential both to train the immune system against cancer cells and to generate an immunological memory, resulting in long-lasting anti-tumor effects. However, despite promising results in phase I and II studies, most of the concepts finally failed. There are some critical aspects in development and application of cancer vaccines that may decide on their efficiency. The time point and frequency of medication, usage of an adequate immune adjuvant, the vaccine's immunogenic potential, and the tumor burden of the patient are crucial. Whole tumor cell vaccines have advantages compared to peptide-based ones since a variety of tumor antigens (TAs) are present. The master requirements of cell-based, therapeutic tumor vaccines are the complete inactivation of the tumor cells and the increase of their immunogenicity. Since the latter is highly connected with the cell death modality, the inactivation procedure of the tumor cell material may significantly influence the vaccine's efficiency. We therefore also introduce high hydrostatic pressure (HHP) as an innovative inactivation technology for tumor cell-based vaccines and outline that HHP efficiently inactivates tumor cells by enhancing their immunogenicity. Finally studies are presented proving that anti-tumor immune responses can be triggered by combining RT with selected

  1. Antitumor and apoptotic effects of cucurbitacin a in A-549 lung ...

    African Journals Online (AJOL)

    Background: The main aim of this study was to demonstrate the antitumor potential of cucurbitacin A on A-549 NSCLC (non-small cell lung cancer cells). The effects of Cucurbitacin A on apoptotic induction, cell physic, cell cycle failure and m-TOR/PI3K/Akt signalling pathway were also investigated in the present study.

  2. Anti-tumor potential of total alkaloid extract of Prosopis juliflora DC ...

    African Journals Online (AJOL)

    The total alkaloid extract from Prosopis juliflora DC. leaves was obtained using acid/base modified extraction method. The in vitro anti-tumor potential of the extract was evaluated using MTT (3-(4,5- dimethythiazol-2yl)2,5-diphenyl tetrazolium bromide) based cytotoxicity monitoring after 24, 48 and 72 h exposure of the ...

  3. Inhibitory efficacy of the quantified prunellae spica extract on H22 tumor bearing mice

    Science.gov (United States)

    Wang, Zhi-ping; Chen, Tong-sheng

    2013-02-01

    Hepatocarcinoma, a malignant cancer, threaten human life badly. It is a current issue to seek the effective natural remedy from plant to treat cancer due to the resistence of the advanced hepatocarcinoma to chemotherapy. In this report, we assessed the antitumor activity of a prunellae spica aqueous extract (PSE) in vitro and in vivo. PSE was quantified by HPLC and UV. MTT assay showed that PSE did not effectively inhibit the growth of H22 cells. The in vivo anti-tumor activity was assessed by using the mice bearing H22 tumor. In vivo studies showed the higher antitumor efficacy of PSE without significant side effect assessed by the reduced tumor weight, and the extended survival time of the mice bearing H22 solid and ascites tumor. Collectively, PSE is a promising Chinese medicinal herb for treating hepatocarcinoma.

  4. Antitumor activity of biflorin, an o-naphthoquinone isolated from Capraria biflora.

    Science.gov (United States)

    Vasconcellos, Marne Carvalho de; Bezerra, Daniel Pereira; Fonseca, Aluísio Marques; Pereira, Márcio Roberto Pinho; Lemos, Telma Leda Gomes; Pessoa, Otília Deusdênia Loiola; Pessoa, Cláudia; Moraes, Manoel Odorico de; Alves, Ana Paula Negreiros Nunes; Costa-Lotufo, Letícia Veras

    2007-08-01

    Pharmacological studies with an aqueous extract obtained from leaves of Capraria biflora showed potent cytotoxic, analgesic, antimicrobial and anti-inflammatory activities. It has been demonstrated that biflorin possesses an in vitro cytotoxic activity against tumor cells. The in vivo antitumor activity of biflorin was evaluated on two mouse models, sarcoma 180 and Ehrlich carcinoma. Biflorin was active against both tumors with a very similar profile. In addition, biflorin was also able to increase the response elicited by 5-FU in mice inoculated with both tumors. The results showed a decrease in Ki67 staining in tumor cells from treated-animals when compared with non-treated groups, which suggests an inhibition of tumor proliferation rate. Histopathological analysis from kidneys and liver showed that biflorin possessed weak and reversible toxic effects. It was also demonstrated that biflorin acts as an immunoadjuvant agent, rising the production of ovalbumin-specific antibodies and inducing a discreet increase of the white pulp and nest of megakaryocytic in spleen of treated mice, which can be related to its antitumor properties.

  5. Esters of pyrazinoic acid are active against pyrazinamide-resistant strains of Mycobacterium tuberculosis and other naturally resistant mycobacteria in vitro and ex vivo within macrophages.

    KAUST Repository

    Pires, David

    2015-10-05

    Pyrazinamide (PZA) is active against major Mycobacterium tuberculosis species (M. tuberculosis, M. africanum, and M. microti), but not against M. bovis and M. avium. The latter two are mycobacteria species involved in human and cattle tuberculosis and in HIV co-infections, respectively. PZA is a first-line agent for the treatment of human tuberculosis and requires activation by a mycobacterial pyrazinamidase to form the active metabolite pyrazinoic acid (POA). As a result of this mechanism, resistance to PZA as often found in tuberculosis patients is caused by point mutations in pyrazinamidase. In previous work, we have shown that POA esters and amides synthesized in our laboratory were stable in plasma. Although the amides did not present significant activity, the esters were active against sensitive mycobacteria at concentrations 5-to-10 fold lower than those of PZA. Here, we report that these POA derivatives possess antibacterial efficacy in vitro and ex vivo against several species and strains of Mycobacterium with natural or acquired resistance to PZA, including M. bovis and M. avium. Our results indicate that the resistance was probably overcome by cleavage of the prodrugs into POA and a long-chain alcohol. Although it is not possible to rule out that the esters may have intrinsic activity per se, we bring evidence here that long-chain fatty alcohols possess a significant anti-mycobacterial effect against PZA-resistant species and strains and are not mere inactive promoieties. These findings may lead to candidate dual-drugs having enhanced activity against both PZA-susceptible and PZA-resistant isolates and being suitable for clinical development.

  6. Antitumor activity of extract and isolated compounds from Drechslera rostrata and Eurotium tonophilum

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    Fatmah A.S. Alasmary

    2018-02-01

    Full Text Available Total extracts of Drechslera rostrata and Eurotium tonophilum in addition of two isolated compounds from their cultures [di-2-ethylhexyl phthalate (H1 and 1,8-Dihydroxy-3-methoxy-6-methyl-anthraquinone (H2] were tested for their antitumor activity using four human carcinoma cell lines. Antitumor activity was assessed by performing MTT assay to check the % cell viability. The % viability of HCT-116 (colon carcinoma, HeLa (cervical carcinoma, HEp-2 (larynx carcinoma and HepG-2 (hepatocellular carcinoma cells decreased after treatment with Drechslera rostrata and Eurotium tonophilum extracts, these effects were ranged from 059.0 ±  0.1 to 217.0  ±  0.3 µg/ml on all types of cancer cells. The best activity was recorded for Eurotium tonpholium extract (054.5 ± 0.3, 059.0 ± 0.5 and 059.0 ± 0.1 for HEp-2, Hela, and HepG-2 respectively. The isolated compounds (H1&H2 were found to be responsible about the activities because they recorded the lowest IC50 on tested cell lines with range of 9.5–20.3 μg/ml. Vinblastine sulphate was used as a reference standard and showed in vitro anticancer activity. This study demonstrated that all extracts and isolated compounds have antitumor activity against HCT-116, HeLa, HEp-2 and HepG-2 cells.

  7. Antitumor Action of a Novel Histone Deacetylase Inhibitor, YF479, in Breast Cancer

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    Tao Zhang

    2014-08-01

    Full Text Available Accumulating evidence demonstrates important roles for histone deacetylase in tumorigenesis (HDACs, highlighting them as attractive targets for antitumor drug development. Histone deactylase inhibitors (HDACIs, which have shown favorable anti-tumor activity with low toxicity in clinical investigations, are a promising class of anticancer therapeutics. Here, we screened our compound library to explore small molecules that possess anti-HDAC activity and identified a novel HDACI, YF479. Suberoylanilide hydroxamic acid (SAHA, which was the first approved HDAC inhibitor for clinical treatment by the FDA, was as positive control in our experiments. We further demonstrated YF479 abated cell viability, suppressed colony formation and tumor cell motility in vitro. To investigate YF479 with superior pharmacodynamic properties, we developed spontaneous and experimental breast cancer animal models. Our results showed YF479 significantly inhibited breast tumor growth and metastasis in vivo. Further study indicated YF479 suppressed both early and end stages of metastatic progression. Subsequent adjuvant chemotherapy animal experiment revealed the elimination of local-regional recurrence (LRR and distant metastasis by YF479. More important, YF479 remarkably prolonged the survival of tumor-bearing mice. Intriguingly, YF479 displayed more potent anti-tumor activity in vitro and in vivo compared with SAHA. Together, our results suggest that YF479, a novel HDACI, inhibits breast tumor growth, metastasis and recurrence. In light of these results, YF479 may be an effective therapeutic option in clinical trials for patients burdened by breast cancer.

  8. Activation of antitumor immune responses by Ganoderma formosanum polysaccharides in tumor-bearing mice.

    Science.gov (United States)

    Wang, Cheng-Li; Lu, Chiu-Ying; Hsueh, Ying-Chao; Liu, Wen-Hsiung; Chen, Chun-Jen

    2014-11-01

    Fungi of the genus Ganoderma are basidiomycetes that have been used as traditional medicine in Asia and have been shown to exhibit various pharmacological activities. We recently found that PS-F2, a polysaccharide fraction purified from the submerged culture broth of Ganoderma formosanum, stimulates the maturation of dendritic cells and primes a T helper 1 (Th1)-polarized adaptive immune response in vivo. In this study, we investigated whether the immune adjuvant function of PS-F2 can stimulate antitumor immune responses in tumor-bearing mice. Continuous intraperitoneal or oral administration of PS-F2 effectively suppressed the growth of colon 26 (C26) adenocarcinoma, B16 melanoma, and sarcoma 180 (S180) tumor cells in mice without adverse effects on the animals' health. PS-F2 did not cause direct cytotoxicity on tumor cells, and it lost the antitumor effect in mice with severe combined immunodeficiency (SCID). CD4(+) T cells, CD8(+) T cells, and serum from PS-F2-treated tumor-bearing mice all exhibited antitumor activities when adoptively transferred to naïve animals, indicating that PS-F2 treatment stimulates tumor-specific cellular and humoral immune responses. These data demonstrate that continuous administration of G. formosanum polysaccharide PS-F2 can activate host immune responses against ongoing tumor growth, suggesting that PS-F2 can potentially be developed into a preventive/therapeutic agent for cancer immunotherapy.

  9. Immunological and antitumor effects of IL-23 as a cancer vaccine adjuvant

    NARCIS (Netherlands)

    Overwijk, Willem W.; de Visser, Karin E.; Tirion, Felicia H.; de Jong, Laurina A.; Pols, Thijs W. H.; van der Velden, Yme U.; van den Boorn, Jasper G.; Keller, Anna M.; Buurman, Wim A.; Theoret, Marc R.; Blom, Bianca; Restifo, Nicholas P.; Kruisbeek, Ada M.; Kastelein, Robert A.; Haanen, John B. A. G.

    2006-01-01

    The promising, but modest, clinical results of many human cancer vaccines indicate a need for vaccine adjuvants that can increase both the quantity and the quality of vaccine-induced, tumor-specific T cells. In this study we tested the immunological and antitumor effects of the proinflammatory

  10. Evaluation of antitumor activity and in vivo antioxidant status of Anthocephalus cadamba on Ehrlich ascites carcinoma treated mice.

    Science.gov (United States)

    Dolai, Narayan; Karmakar, Indrajit; Suresh Kumar, R B; Kar, Biswakanth; Bala, Asis; Haldar, Pallab Kanti

    2012-08-01

    Anthocephalus cadamba (Roxb.) Miq. (Family: Rubiaceae) is commonly known as "Kadamba" in Sanskrit and Hindi in India. Various parts of this plant have been used as a folk medicine for the treatment of tumor, wound healing, inflammation and as a hypoglycemic agent. The purpose of this investigation was to evaluate the antitumor activity and antioxidant status of defatted methanol extract of A. cadamba (MEAC) on Ehrlich ascites carcinoma (EAC) treated mice. In vitro cytotoxicity assay has been evaluated by using the trypan blue method. The determination of in vivo antitumor activity was performed by using different EAC cells (2 × 10(6) cells, i.p.) inoculated mice groups (n=12). The groups were treated for 9 consecutive days with MEAC at the doses of 200 and 400 mg/kg b.w. respectively. After 24h of last dose and 18 h of fasting, half of the mice were sacrificed and the rest were kept alive for assessment of increase in life span. The antitumor potential of MEAC was assessed by evaluating tumor volume, viable and nonviable tumor cell count, tumor weight, hematological parameters and biochemical estimations. Furthermore, antioxidant parameters were assayed by estimating liver and kidney tissue enzymes. MEAC showed direct cytotoxicity on EAC cell line in a dose dependant manner. MEAC exhibited significant (P<0.01) decrease in the tumor volume, viable cell count, tumor weight and elevated the life span of EAC tumor bearing mice. The hematological profile, biochemical estimations and tissue antioxidant assay were reverted to normal level in MEAC treated mice. Experimental results revealed that MEAC possesses potent antitumor and antioxidant properties. Further research is going on to find out the active principle(s) of MEAC for better understanding of mechanism of its antitumor and antioxidant activity. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  11. Optimizing the dosing schedule of l-asparaginase improves its anti-tumor activity in breast tumor-bearing mice

    Directory of Open Access Journals (Sweden)

    Shoya Shiromizu

    2018-04-01

    Full Text Available Proliferation of acute lymphoblastic leukemic cells is nutritionally dependent on the external supply of asparagine. l-asparaginase, an enzyme hydrolyzing l-asparagine in blood, is used for treatment of acute lymphoblastic leukemic and other related blood cancers. Although previous studies demonstrated that l-asparaginase suppresses the proliferation of cultured solid tumor cells, it remains unclear whether this enzyme prevents the growth of solid tumors in vivo. In this study, we demonstrated the importance of optimizing dosing schedules for the anti-tumor activity of l-asparaginase in 4T1 breast tumor-bearing mice. Cultures of several types of murine solid tumor cells were dependent on the external supply of asparagine. Among them, we selected murine 4T1 breast cancer cells and implanted them into BALB/c female mice kept under standardized light/dark cycle conditions. The growth of 4T1 tumor cells implanted in mice was significantly suppressed by intravenous administration of l-asparaginase during the light phase, whereas its administration during the dark phase failed to show significant anti-tumor activity. Decreases in plasma asparagine levels due to the administration of l-asparaginase were closely related to the dosing time-dependency of its anti-tumor effects. These results suggest that the anti-tumor efficacy of l-asparaginase in breast tumor-bearing mice is improved by optimizing the dosing schedule. Keywords: l-asparaginase, Asparagine, Solid tumor, Chrono-pharmacotherapy

  12. Optimizing the dosing schedule of l-asparaginase improves its anti-tumor activity in breast tumor-bearing mice.

    Science.gov (United States)

    Shiromizu, Shoya; Kusunose, Naoki; Matsunaga, Naoya; Koyanagi, Satoru; Ohdo, Shigehiro

    2018-04-01

    Proliferation of acute lymphoblastic leukemic cells is nutritionally dependent on the external supply of asparagine. l-asparaginase, an enzyme hydrolyzing l-asparagine in blood, is used for treatment of acute lymphoblastic leukemic and other related blood cancers. Although previous studies demonstrated that l-asparaginase suppresses the proliferation of cultured solid tumor cells, it remains unclear whether this enzyme prevents the growth of solid tumors in vivo. In this study, we demonstrated the importance of optimizing dosing schedules for the anti-tumor activity of l-asparaginase in 4T1 breast tumor-bearing mice. Cultures of several types of murine solid tumor cells were dependent on the external supply of asparagine. Among them, we selected murine 4T1 breast cancer cells and implanted them into BALB/c female mice kept under standardized light/dark cycle conditions. The growth of 4T1 tumor cells implanted in mice was significantly suppressed by intravenous administration of l-asparaginase during the light phase, whereas its administration during the dark phase failed to show significant anti-tumor activity. Decreases in plasma asparagine levels due to the administration of l-asparaginase were closely related to the dosing time-dependency of its anti-tumor effects. These results suggest that the anti-tumor efficacy of l-asparaginase in breast tumor-bearing mice is improved by optimizing the dosing schedule. Copyright © 2018 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

  13. Aluminum resistance transcription factor 1 (ART1) contributes to natural variation in rice aluminum resistance

    Science.gov (United States)

    Transcription factors (TFs) mediate stress resistance indirectly via physiological mechanisms driven by the array of genes they regulate. Therefore, when studying TF-mediated stress resistance, it is important to understand how TFs interact with different genetic backgrounds. Here, we fine-mapped th...

  14. Frequency of Natural Resistance within NS5a Replication Complex Domain in Hepatitis C Genotypes 1a, 1b: Possible Implication of Subtype-Specific Resistance Selection in Multiple Direct Acting Antivirals Drugs Combination Treatment

    Directory of Open Access Journals (Sweden)

    Sabrina Bagaglio

    2016-03-01

    Full Text Available Different HCV subtypes may naturally harbor different resistance selection to anti-NS5a inhibitors. 2761 sequences retrieved from the Los Alamos HCV database were analyzed in the NS5a domain 1, the target of NS5a inhibitors. The NS5a resistance-associated polymorphisms (RAPs were more frequently detected in HCV G1b compared to G1a. The prevalence of polymorphisms associated with cross-resistance to compounds in clinical use (daclatasvir, DCV, ledipasvir, LDV, ombitasvir, and OMV or scheduled to come into clinical use in the near future (IDX719, elbasvir, and ELV was higher in G1b compared to G1a (37/1552 (2.4% in 1b sequences and 15/1209 (1.2% in 1a isolates, p = 0.040. Interestingly, on the basis of the genotype-specific resistance pattern, 95 (6.1% G1b sequences had L31M RAP to DCV/IDX719, while 6 sequences of G1a (0.5% harbored L31M RAP, conferring resistance to DCV/LDV/IDX719/ELV (p < 0.0001. Finally, 28 (2.3% G1a and none of G1b isolates harbored M28V RAP to OMV (p < 0.0001. In conclusion, the pattern of subtype-specific resistance selection in the naturally occurring strains may guide the treatment option in association with direct acting antivirals (DAAs targeting different regions, particularly in patients that are difficult to cure, such as those with advanced liver disease or individuals who have failed previous DAAs.

  15. [Vancomycin-resistant enterococci - the nature of resistance and risk of transmission from animals to humans].

    Science.gov (United States)

    Hermanovská, Lýdia; Bardoň, Jan; Čermák, Pavel

    2016-06-01

    Enterococci are part of the normal intestinal flora of humans and animals. Under certain circumstances, they are capable of extraintestinal conversion to opportunistic pathogens. They cause endogenous as well as exogenous community and nosocomial infections. The gastrointestinal tract of mammals provides them with favorable conditions for acquisition and spread of resistance genes, for example to vancomycin (van), from other symbiotic bacteria. Thus, vancomycin-resistant enterococci (VRE) become potential reservoirs and vectors of the van genes. Their occurrence in the population of the Czech Republic was first reported by Kolář et al. in 1997. Some variants of the vanA gene cluster carried on Tn1546 which encode resistance to vancomycin are identical in humans and in animals. It means that animals, especially cattle, poultry and pigs, could be an important reservoir of VRE for humans. Kolář and Bardoň detected VRE in animals in the Czech Republic for the first time in 2000. In Europe, the glycopeptide antibiotic avoparcin, used as a growth stimulator, is responsible for selection of VRE strains in animals. Strains of Enterococcus faecium from animals may offer genes of antimicrobial resistance to other enterococci or they can be directly dangerous to human. This is demonstrated by finding isolates of E. faecalis from human patients and from pigs having very similar profiles of resistance and virulence genes. The goal of the paper was to point out the similarity between isolates of human and animal strains of enterococci resistant to vancomycin, and the possibility of their bilateral transfer between humans and animals.

  16. Natural CD8{sup +}25{sup +} regulatory T cell-secreted exosomes capable of suppressing cytotoxic T lymphocyte-mediated immunity against B16 melanoma

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Yufeng; Zhang, Xueshu; Zhao, Tuo; Li, Wei; Xiang, Jim, E-mail: jim.xiang@saskcancer.ca

    2013-08-16

    Highlights: •CD8{sup +}25{sup +} regulatory T cells secrete tolerogenic exosomes. •CD8{sup +}25{sup +} regulatory T cell-derived exosomes exhibit immunosuppressive effect. •CD8{sup +}25{sup +} regulatory T cell-derived exosomes inhibit antitumor immunity. -- Abstract: Natural CD4{sup +}25{sup +} and CD8{sup +}25{sup +} regulatory T (Tr) cells have been shown to inhibit autoimmune diseases. Immune cells secrete exosomes (EXOs), which are crucial for immune regulation. However, immunomodulatory effect of natural Tr cell-secreted EXOs is unknown. In this study, we purified natural CD8{sup +}25{sup +} Tr cells from C57BL/6 mouse naive CD8{sup +} T cells, and in vitro amplified them with CD3/CD28 beads. EXOs (EXO{sub Tr}) were purified from Tr cell’s culture supernatants by differential ultracentrifugation and analyzed by electron microscopy, Western blot and flow cytometry. Our data showed that EXO{sub Tr} had a “saucer” or round shape with 50–100 nm in diameter, contained EXO-associated markers LAMP-1 and CD9, and expressed natural Tr cell markers CD25 and GITR. To assess immunomodulatory effect, we i.v. immunized C57BL/6 mice with ovalbumin (OVA)-pulsed DCs (DC{sub OVA}) plus Tr cells or EXO{sub Tr}, and then assessed OVA-specific CD8{sup +} T cell responses using PE-H-2K{sup b}/OVA tetramer and FITC-anti-CD8 antibody staining by flow cytometry and antitumor immunity in immunized mice with challenge of OVA-expressing BL6–10{sub OVA} melanoma cells. We demonstrated that DC{sub OVA}-stimulated CD8{sup +} T cell responses and protective antitumor immunity significantly dropped from 2.52% to 1.08% and 1.81% (p < 0.05), and from 8/8 to 2/8 and 5/8 mice DC{sub OVA} (p < 0.05) in immunized mice with co-injection of Tr cells and EXO{sub Tr}, respectively. Our results indicate that natural CD8{sup +}25{sup +} Tr cell-released EXOs, alike CD8{sup +}25{sup +} Tr cells, can inhibit CD8{sup +} T cell responses and antitumor immunity. Therefore, EXOs derived from

  17. Assessment of the Resistance to External Factors of Low-Density Polyethylene Modified with Natural Fillers

    Directory of Open Access Journals (Sweden)

    Karolina Głogowska

    2017-12-01

    Full Text Available The study reports the results of investigation of basic processing and thermal properties of low-density polyethylene modified with two types of natural filler: wheat bran and pumpkin seed hulls, their content ranging from 5% to 15% relative to the matrix. In addition, the physical properties of the produced granulates are determined, i.e. the relationship between their density and the applied contents of the tested fillers. Furthermore, the study reports the results concerning the longitudinal shrinkage, abrasion resistance and cold water absorption of injection molded tensile specimens.

  18. Natural Products from Mangrove Actinomycetes

    Directory of Open Access Journals (Sweden)

    Dong-Bo Xu

    2014-05-01

    Full Text Available Mangroves are woody plants located in tropical and subtropical intertidal coastal regions. The mangrove ecosystem is becoming a hot spot for natural product discovery and bioactivity survey. Diverse mangrove actinomycetes as promising and productive sources are worth being explored and uncovered. At the time of writing, we report 73 novel compounds and 49 known compounds isolated from mangrove actinomycetes including alkaloids, benzene derivatives, cyclopentenone derivatives, dilactones, macrolides, 2-pyranones and sesquiterpenes. Attractive structures such as salinosporamides, xiamycins and novel indolocarbazoles are highlighted. Many exciting compounds have been proven as potential new antibiotics, antitumor and antiviral agents, anti-fibrotic agents and antioxidants. Furthermore, some of their biosynthetic pathways have also been revealed. This review is an attempt to consolidate and summarize the past and the latest studies on mangrove actinomycetes natural product discovery and to draw attention to their immense potential as novel and bioactive compounds for marine drugs discovery.

  19. Utilization of metabonomics to identify serum biomarkers in murine H22 hepatocarcinoma and deduce antitumor mechanism of Rhizoma Paridis saponins.

    Science.gov (United States)

    Qiu, Peiyu; Man, Shuli; Yang, He; Fan, Wei; Yu, Peng; Gao, Wenyuan

    2016-08-25

    Murine H22 hepatocarcinoma model is so popular to be used for the preclinical anticancer candidate's evaluation. However, the metabolic biomarkers of this model were not identified. Meanwhile, Rhizoma Paridis saponins (RPS) as natural products have been found to show strong antitumor activity, while its anti-cancer mechanism is not clear. To search for potential metabolite biomarkers of this model, serum metabonomics approach was applied to detect the variation of metabolite biomarkers and the related metabolism genes and signaling pathway were used to deduce the antitumor mechanisms of RPS. As a result, ten serum metabolites were identified in twenty-four mice including healthy mice, non-treated cancer mice, RPS-treated cancer mice and RPS-treated healthy mice. RPS significantly decreased tumor weight correlates to down-regulating lactate, acetate, N-acetyl amino acid and glutamine signals (p < 0.05), which were marked metabolites screened according to the very important person (VIP), loading plot and receiver operating characteristic curve (ROC) tests. For the analysis of metabolic enzyme related genes, RPS reversed the aerobic glycolysis through activating tumor suppressor p53 and PTEN, and suppressed FASN to inhibit lipogenesis. What's more, RPS repressed Myc and GLS expression and decreased glutamine level. The regulating PI3K/Akt/mTOR and HIF-1α/Myc/Ras networks also participated in these metabolic changes. Taken together, RPS suppressed ATP product made the tumor growth slow, which indicated a good anti-cancer effect and new angle for understanding the mechanism of RPS. In conclusion, this study demonstrated that the utility of (1)H NMR metabolic profiles taken together with tumor weight and viscera index was a promising screening tool for evaluating the antitumor effect of candidates. In addition, RPS was a potent anticancer agent through inhibiting cancer cellular metabolism to suppress proliferation in hepatoma H22 tumor murine, which promoted the

  20. Potent antitumor activities of recombinant human PDCD5 protein in combination with chemotherapy drugs in K562 cells

    International Nuclear Information System (INIS)

    Shi, Lin; Song, Quansheng; Zhang, Yingmei; Lou, Yaxin; Wang, Yanfang; Tian, Linjie; Zheng, Yi; Ma, Dalong; Ke, Xiaoyan; Wang, Ying

    2010-01-01

    Conventional chemotherapy is still frequently used. Programmed cell death 5 (PDCD5) enhances apoptosis of various tumor cells triggered by certain stimuli and is lowly expressed in leukemic cells from chronic myelogenous leukemia patients. Here, we describe for the first time that recombinant human PDCD5 protein (rhPDCD5) in combination with chemotherapy drugs has potent antitumor effects on chronic myelogenous leukemia K562 cells in vitro and in vivo. The antitumor efficacy of rhPDCD5 protein with chemotherapy drugs, idarubicin (IDR) or cytarabine (Ara-C), was examined in K562 cells in vitro and K562 xenograft tumor models in vivo. rhPDCD5 protein markedly increased the apoptosis rates and decreased the colony-forming capability of K562 cells after the combined treatment with IDR or Ara-C. rhPDCD5 protein by intraperitoneal administration dramatically improved the antitumor effects of IDR treatment in the K562 xenograft model. The tumor sizes and cell proliferation were significantly decreased; and TUNEL positive cells were significantly increased in the combined group with rhPDCD5 protein and IDR treatment compared with single IDR treatment groups. rhPDCD5 protein, in combination with IDR, has potent antitumor effects on chronic myelogenous leukemia K562 cells and may be a novel and promising agent for the treatment of chronic myelogenous leukemia.

  1. Therapy for BRAFi-Resistant Melanomas: Is WNT5A the Answer?

    International Nuclear Information System (INIS)

    Prasad, Chandra Prakash; Mohapatra, Purusottam; Andersson, Tommy

    2015-01-01

    In recent years, scientists have advocated the use of targeted therapies in the form of drugs that modulate genes and proteins that are directly associated with cancer progression and metastasis. Malignant melanoma is a dreadful cancer type that has been associated with the rapid dissemination of primary tumors to multiple sites, including bone, brain, liver and lungs. The discovery that approximately 40%–50% of malignant melanomas contain a mutation in BRAF at codon 600 gave scientists a new approach to tackle this disease. However, clinical studies on patients have shown that although BRAFi (BRAF inhibitors) trigger early anti-tumor responses, the majority of patients later develop resistance to the therapy. Recent studies have shown that WNT5A plays a key role in enhancing the resistance of melanoma cells to BRAFi. The focus of the current review will be on melanoma development, signaling pathways important to acquired resistance to BRAFi, and why WNT5A inhibitors are attractive candidates to be included in combinatorial therapies for melanoma

  2. Transcutaneous carbon dioxide enhances the antitumor effect of radiotherapy on oral squamous cell carcinoma.

    Science.gov (United States)

    Iwata, Eiji; Hasegawa, Takumi; Ueha, Takeshi; Takeda, Daisuke; Saito, Izumi; Kawamoto, Teruya; Akisue, Toshihiro; Sakai, Yoshitada; Sasaki, Ryohei; Kuroda, Ryosuke; Komori, Takahide

    2018-05-16

    Radiotherapy (RT) is one of the main treatment modalities for oral squamous cell carcinoma (OSCC), however, radioresistance is a major impediment to its clinical success and poses as a concern that needs to be addressed. Tumor hypoxia is known to be significantly associated with radioresistance in various malignancies, hence, resolving the hypoxic state of a tumor may improve the antitumor effect of RT on OSCC. We have previously revealed that transcutaneous CO2 induced mitochondrial apoptosis and suppressed tumor growth in OSCC by resolving hypoxia. Considering the previous study, we hypothesized that transcutaneous CO2 may enhance the antitumor effect of RT on OSCC by improving intratumoral hypoxia, thereby overcoming radioresistance. In the present study, the combination of transcutaneous CO2 and RT significantly inhibited tumor growth compared with other treatments. This combination therapy also led to decreased expression of HIF-1α in parallel with increased expression of the cleaved forms of caspase-3-8-9 and PARP, which play essential roles in mitochondrial apoptosis. Additionally, the combination therapy increased the expression of ROS modulator 1 and subsequent mitochondrial ROS production, compared to RT alone. These results indicated that transcutaneous CO2 could potentially improve the antitumor effect of RT by decreasing the intratumoral hypoxia and increasing the mitochondrial apoptosis. Our findings indicated that CO2 therapy may be a novel adjuvant therapy in combination with RT for OSCC.

  3. Cytotoxic, antitumor and leukocyte migration activities of resveratrol and sitosterol present in the hidroalcoholic extract of Cissus sicyoides L., Vitaceae, leaves

    Directory of Open Access Journals (Sweden)

    Flávia R. S. Lucena

    2010-05-01

    Full Text Available Cissus sicyoides L. pertains to the Vitaceae family. It is popularly known as "insulina, cipo-pucá, bejuco caro, puci, anil trepador". A vasoconstrictor effect and an antibacterial activity have also been allocated to it. In Brazil, C. sicyoides was evaluated for its anticonvulsant and anti-diabetc properties. Phytochemistry studies identified and isolated sitosterol and resveratrol compounds from its aerial parts which are pointed out as having antitumor activities. The goal of this study was to investigate the cytotoxic and antitumor activities of Cissus sicyoides hydroalcoholic extract as well as its ability to repair leukocytes cells to injured tissue. Cissus sicyoides did not demonstrate cytotoxic activity but showed an inhibition of tumor growth in face of the tumors tested. The extract had a strong chemotactic effect on the twenty four hours period after treatment. The hidroalchoolic extract of Cissus sicyoides presented antitumor activity which was prompted by T lymphocytes recruitment to the local lesion and suggests a new pathway to antitumor activity by activation of lymphoid lineage.

  4. Liposomal n-butylidenephthalide protects the drug from oxidation and enhances its antitumor effects in glioblastoma multiforme

    Directory of Open Access Journals (Sweden)

    Lin YL

    2015-09-01

    Full Text Available Yu-Ling Lin,1,2,* Kai-Fu Chang,3,* Xiao-Fan Huang,3 Che-Lun Hung,4 Shyh-Chang Chen,5 Wan-Ru Chao,6,7 Kuang-Wen Liao,1,8 Nu-Man Tsai3,9 1College of Biological Science and Technology, 2Center for Bioinformatics Research, National Chiao Tung University, Hsinchu, 3School of Medical Laboratory and Biotechnology, Chung Shan Medical University, 4Department of Computer Science and Communication Engineering, Providence University, 5Department of Pathology and Laboratory Medicine, Taichung Veterans General Hospital, 6Institute of Medicine, Chung Shan Medical University, 7Department of Pathology, Chung Shan Medical University and Chung Shan Medical University Hospital, Taichung, 8Institute of Molecular Medicine and Bioengineering, National Chiao Tung University, Hsinchu, 9Clinical Laboratory, Chung Shan Medical University Hospital, Taichung, Taiwan *These authors contributed equally to this work Background: The natural compound n-butylidenephthalide (BP can pass through the blood–brain barrier to inhibit the growth of glioblastoma multiforme tumors. However, BP has an unstable structure that reduces its antitumor activity and half-life in vivo.Objective: The aim of this study is to design a drug delivery system to encapsulate BP to enhance its efficacy by improving its protection and delivery.Methods: To protect its structural stability against protein-rich and peroxide solutions, BP was encapsulated into a lipo-PEG-PEI complex (LPPC. Then, the cytotoxicity of BP/LPPC following preincubation in protein-rich, acid/alkaline, and peroxide solutions was analyzed by MTT. Cell uptake of BP/LPPC was also measured by confocal microscopy. The therapeutic effects of BP/LPPC were analyzed in xenograft mice following intratumoral and intravenous injections.Results: When BP was encapsulated in LPPC, its cytotoxicity was maintained following preincubation in protein-rich, acid/alkaline, and peroxide solutions. The cytotoxic activity of encapsulated BP was higher than

  5. Antitumor efficacy of a novel CLA-PTX microemulsion against brain tumors: in vitro and in vivo findings.

    Science.gov (United States)

    Li, Dan; Yang, Ke; Li, Jie-Si; Ke, Xi-Yu; Duan, Yu; Du, Ruo; Song, Ping; Yu, Ke-Fu; Ren, Wei; Huang, Dan; Li, Xing-Huo; Hu, Xin; Zhang, Xuan; Zhang, Qiang

    2012-01-01

    Considering the observations that linoleic acid conjugated with paclitaxel (CLA-PTX) possesses antitumor activity against brain tumors, is able to cross the blood-brain barrier, but has poor water solubility, the purpose of this study was to prepare a novel CLA-PTX microemulsion and evaluate its activity against brain tumors in vitro and in vivo. The in vitro cytotoxicity of a CLA-PTX microemulsion was investigated in C6 glioma cells. The in vivo antitumor activity of the CLA-PTX microemulsion was evaluated in tumor-bearing nude mice and rats. The pharmacokinetics of the CLA-PTX microemulsion were investigated in rats, and its safety was also evaluated in mice. The average droplet size of the CLA-PTX microemulsion was approximately 176.3 ± 0.8 nm and the polydispersity index was 0.294 ± 0.024. In vitro cytotoxicity results showed that the IC(50) of the CLA-PTX microemulsion was 1.61 ± 0.83 μM for a C6 glioma cell line, which was similar to that of free paclitaxel and CLA-PTX solution (P > 0.05). The antitumor activity of the CLA-PTX microemulsion against brain tumors was confirmed in our in vivo C6 glioma tumor-bearing nude mice as well as in a rat model. In contrast, Taxol(®) had almost no significant antitumor effect in C6 glioma tumor-bearing rats, but could markedly inhibit growth of C6 tumors in C6 glioma tumor-bearing nude mice. The pharmacokinetic results indicated that CLA-PTX in solution has a much longer circulation time and produces higher drug plasma concentrations compared with the CLA-PTX microemulsion. The results of the acute toxicity study showed that the LD(50) of CLA-PTX solution was 103.9 mg/kg. In contrast, the CLA-PTX microemulsion was well tolerated in mice when administered at doses up to 200 mg/kg. CLA-PTX microemulsion is a novel formulation with significant antitumor efficacy in the treatment of brain tumors, and is safer than CLA-PTX solution.

  6. Multilineage hematopoietic recovery with concomitant antitumor effects using low dose Interleukin-12 in myelosuppressed tumor-bearing mice

    Directory of Open Access Journals (Sweden)

    Miller Joseph D

    2008-05-01

    Full Text Available Abstract Background Interleukin-12 (IL-12 is a cytokine well known for its role in immunity. A lesser known function of IL-12 is its role in hematopoiesis. The promising data obtained in the preclinical models of antitumor immunotherapy raised hope that IL-12 could be a powerful therapeutic agent against cancer. However, excessive clinical toxicity, largely due to repeat dose regimens, and modest clinical response observed in the clinical trials have pointed to the necessity to design protocols that minimize toxicity without affecting the anti-tumor effect of IL-12. We have focused on the lesser known role of IL-12 in hematopoiesis and hypothesized that an important clinical role for IL-12 in cancer may be as an adjuvant hematological cancer therapy. In this putative clinical function, IL-12 is utilized for the prevention of cancer therapy-related cytopenias, while providing concomitant anti-tumor responses over and above responses observed with the primary therapy alone. This putative clinical function of IL-12 focuses on the dual role of IL-12 in hematopoiesis and immunity. Methods We assessed the ability of IL-12 to facilitate hematopoietic recovery from radiation (625 rad and chemotherapy (cyclophosphamide in two tumor-bearing murine models, namely the EL4 lymphoma and the Lewis lung cancer models. Antitumor effects and changes in bone marrow cellularity were also assessed. Results We show herein that carefully designed protocols, in mice, utilizing IL-12 as an adjuvant to radiation or chemotherapy yield facile and consistent, multilineage hematopoietic recovery from cancer therapy-induced cytopenias, as compared to vehicle and the clinically-utilized cytokine granulocyte colony-stimulating factor (G-CSF (positive control, while still providing concomitant antitumor responses over and above the effects of the primary therapy alone. Moreover, our protocol design utilizes single, low doses of IL-12 that did not yield any apparent toxicity

  7. A Novel Paclitaxel Microemulsion Containing a Reduced Amount of Cremophor EL: Pharmacokinetics, Biodistribution, and In Vivo Antitumor Efficacy and Safety

    Science.gov (United States)

    Wang, Ying; Wu, Ke-Chun; Zhao, Bing-Xiang; Zhao, Xin; Wang, Xin; Chen, Su; Nie, Shu-Fang; Pan, Wei-San; Zhang, Xuan; Zhang, Qiang

    2011-01-01

    The purpose of this study was to prepare a novel paclitaxel (PTX) microemulsion containing a reduced amount of Cremophor EL (CrEL) which had similar pharmacokinetics and antitumor efficacy as the commercially available PTX injection, but a significantly reduced allergic effect due to the CrEL. The pharmacokinetics, biodistribution, in vivo antitumor activity and safety of PTX microemulsion was evaluated. The results of pharmacokinetic and distribution properties of PTX in the microemulsion were similar to those of the PTX injection. The antitumor efficacy of the PTX microemulsion in OVCRA-3 and A 549 tumor-bearing animals was similar to that of PTX injection. The PTX microemulsion did not cause haemolysis, erythrocyte agglutination or simulative reaction. The incidence and degree of allergic reactions exhibited by the PTX microemulsion group, with or without premedication, were significantly lower than those in the PTX injection group (P microemulsion had similar pharmacokinetics and anti-tumor efficacy to the PTX injection, but a significantly reduced allergic effect due to CrEL, indicating that the PTX microemulsion overcomes the disadvantages of the conventional PTX injection and is one way of avoiding the limitations of current injection product while providing suitable therapeutic efficacy. PMID:21331356

  8. Antioxidant, Anti-Inflammatory, and Antitumor Activities of Cultured Mycelia and Fruiting Bodies of the Elm Oyster Mushroom, Hypsizygus ulmarius (Agaricomycetes).

    Science.gov (United States)

    Greeshma, Panavalappil; Ravikumar, Korattuvalappil S; Neethu, Mangalathmelathil N; Pandey, Meera; Zuhara, Karattuthodi Fathimathu; Janardhanan, Kainoor K

    2016-01-01

    Ethanoic extracts from the fruiting bodies and mycelia of the elm oyster mushroom, Hypsizygus ulmarius, were evaluated for their antioxidant, anti-inflammatory, and antitumor properties. Ethnolic extracts of fruiting body and mycelia showed 88%, 85%, 71%, and 85%, 65%, 70% 2,2-diphenyl-1-picrylhydrazyl, hydroxyl (DPPH) and 2,2'-azinobis (3-ethyl benzothiazolin-6-sulfonic acid) (ABTS) radical-scavenging activities, respectively, at a concentration of 1000 µg/mL. The anti-inflammatory activity was determined using carrageenan- and formalin- induced paw edema models. Diclofenac was used as the standard drug. In both models, the mycelia extract showed higher activity than the fruiting body extract. The antitumor effect of the extracts against Dalton's Lymphoma Ascites cell-line-induced tumors showed significant antitumor activity. Mycochemical analysis confirmed the presence of many pharmacologically active compounds such as phenol, alkaloids, proteins, tannins, and polysaccharides. Among these, polysaccharides and phenolic compounds were present at a higher concentration in both extracts. These compounds might be largely responsible for the mushroom's medicinal properties. The results of this study indicate that H. ulmarius possesses significant antioxidant, anti-inflammatory, and antitumor properties.

  9. Emission of extensively-drug-resistant Acinetobacter baumannii from hospital settings to the natural environment.

    Science.gov (United States)

    Seruga Music, M; Hrenovic, J; Goic-Barisic, I; Hunjak, B; Skoric, D; Ivankovic, T

    2017-08-01

    Acinetobacter baumannii is a leading emerging pathogen that is frequently recovered from patients during hospital outbreaks. The role of environmental A. baumannii reservoirs is therefore of great concern worldwide. To investigate the connection between A. baumannii causing hospital outbreaks and environmental isolates from hospital wastewater, urban sewage and river water as the final natural recipient of wastewaters. Clinical isolates from patients with hospital-acquired pneumonia and environmental isolates from water were collected during a two-month monitoring period. Recovery of A. baumannii was performed using CHROMagar Acinetobacter plates, incubated at 42°C for 48 h. Identification was performed by matrix-assisted laser desorption ionization-time of flight mass spectrometry and analyses of rpoB gene. The antibiotic resistance profiles were interpreted according to criteria given for clinical isolates of A. baumannii. The sequence types (ST) were retrieved by multi-locus sequence typing. Fourteen of 19 isolates recovered from patients, hospital wastewaters, urban sewage and river water belonged to ST-195. The remaining five isolates recovered from patients and river water were assigned to ST-1421. All isolates showed very strong relatedness and clustered into CC92, which corresponds to IC2. All isolates were non-susceptible to at least one agent in all but two or fewer antimicrobial categories, and thus were classified as 'extensively-drug-resistant' (XDR). Heteroresistance to colistin was found in two isolates from hospital wastewater. Close relatedness of clinical and environmental isolates suggests the emission of XDR A. baumannii via the untreated hospital wastewater in the natural environment. Copyright © 2017 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  10. Natural Variation in Elicitation of Defense-Signaling Associates to Field Resistance Against the Spot Blotch Disease in Bread Wheat (Triticum aestivum L.)

    OpenAIRE

    Sandeep Sharma; Ranabir Sahu; Sudhir Navathe; Vinod K. Mishra; Ramesh Chand; Pawan K. Singh; Arun K. Joshi; Shree P. Pandey

    2018-01-01

    Spot blotch, caused by the hemibiotropic fungus Bipolaris sorokiniana, is amongst the most damaging diseases of wheat. Still, natural variation in expression of biochemical traits that determine field resistance to spot blotch in wheat remain unaddressed. To understand how genotypic variations relate to metabolite profiles of the components of defense-signaling and the plant performance, as well as to discover novel sources of resistance against spot blotch, we have conducted field studies us...

  11. Synthesis of a natural product-inspired eight-membered ring lactam library via ring-closing metathesis.

    Science.gov (United States)

    Brown, Neil; Xie, Baohan; Markina, Nataliya; Vandervelde, David; Perchellet, Jean-Pierre H; Perchellet, Elisabeth M; Crow, Kyle R; Buszek, Keith R

    2008-09-01

    We have prepared a novel speculative eight-membered lactam demonstration library based on the skeletal structure of the potent antitumor marine natural product octalactin A. The basic scaffold was readily constructed in a convergent fashion via ring-closing metathesis chemistry from the corresponding diene amides. A cursory examination of the biological properties of the library validates the relevance and significance of these structures.

  12. A streptomycin resistance marker in H. parasuis based on site-directed mutations in rpsL gene to perform unmarked in-frame mutations and to verify natural transformation

    Directory of Open Access Journals (Sweden)

    Ke Dai

    2018-01-01

    Full Text Available Haemophilus parasuis is a member of the family Pasteurellaceae and a major causative agent of Glässer’s disease. This bacterium is normally a benign swine commensal but may become a deadly pathogen upon penetration into multiple tissues, contributing to severe lesions in swine. We have established a successive natural transformation-based markerless mutation system in this species. However, the two-step mutation system requires screening of natural competent cells, and cannot delete genes which regulate natural competence per se. In this study, we successfully obtained streptomycin-resistant derivatives from H. parasuis wild type strain SC1401 by using ethyl methane sulfonate (EMS, CH3SO2OC2H5. Upon sequencing and site-directed mutations, we uncovered that the EMS-induced point mutation in rpsL at codon 43rd (AAA → AGA; K43R or at 88th (AAA → AGA; K88R confers a much higher streptomycin resistance than clinical isolates. We have applied the streptomycin resistance marker as a positive selection marker to perform homologous recombination through conjugation and successfully generated a double unmarked in-frame targeted mutant 1401D88△tfox△arcA. Combined with a natural transformation-based knockout system and this genetic technique, multiple deletion mutants or attenuated strains of H. parasuis can be easily constructed. Moreover, the mutant genetic marker rpsL and streptomycin resistant phenotypes can serve as an effective tool to select naturally competent strains, and to verify natural transformation quantitatively.

  13. Effects of Different Temperatures on the Chemical Structure and Antitumor Activities of Polysaccharides from Cordyceps militaris

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    Eliyas Nurmamat

    2018-04-01

    Full Text Available The effects of different extraction temperatures (4 and 80 °C on the physicochemical properties and antitumor activity of water soluble polysaccharides (CMPs-4 and CMPs-80 from Cordyceps militaris (C. militaris were evaluated in this study. The results of gas chromatography (GC and high-performance gel permeation chromatography (HPGPC showed that a higher extraction temperature could degrade the polysaccharides with 188 kDa, mainly composed of glucose, and increase the dissolution rate of polysaccharides about 308 kDa, mainly consisting of rhamnose and galactose. In addition, the CMPs displayed the same sugar ring and category of glycosidic linkage based on Fourier-transform infrared spectroscopy (FTIR analysis, however, their invisible structural difference occurred in the specific rotation and conformational characteristics according to the results of specific optical rotation measurement and Congo red test. In vitro antitumor experiments indicated that CMPs-4 possessed stronger inhibitory effects on human esophagus cancer Eca-109 cells by inducing cell apoptosis more than CMPs-80 did. These findings demonstrated that the polysaccharides extracted with cold water (4 °C could be applied as a novel alternative chemotherapeutic agent or dietary supplement with its underlying antitumor property.

  14. Immunomodulatory and antitumor effects in vivo by the cytoplasmic fraction of Lactobacillus casei and Bifidobacterium longum.

    Science.gov (United States)

    Lee, Jung-Woo; Shin, Jung-Gul; Kim, Eun Hee; Kang, Hae Eun; Yim, In Been; Kim, Ji Yeon; Joo, Hong-Gu; Woo, Hee Jong

    2004-03-01

    The immunomodulatory and antitumor effects of lactic acid bacteria (LABs) were investigated. Cytoplasmic fraction of Lactobacillus acidophilus, Lactobacillus casei and Bifidobacterium longum were tested for the antiproliferative activity in vitro to SNUC2A, SNU1, NIH/3T3 and Jurkat cell lines by crystal violet assay. All cytoplasmic fraction suppressed proliferation of tumor cells, though L. casei and B. longum were more effective. From these results, cytoplasmic fraction of L. casei and B. longum with Y400 as a control were administered as dietary supplements to Balb/c mice for 2, and 4 consecutive wks. Administration for 4 wks enhanced the number of total T cells, NK cells and MHC class II+ cells, and CD4-CD8+ T cells in flow cytometry analysis. To determine of antitumor activity of LABs preparation in vivo, F9 teratocarcinoma cells were inoculated on mice at 14th day. Body weight was decreased with increased survival rate in all groups with the cytoplasm of LABs. Our results showed that cytoplasmic fraction of LABs had direct antiproliferative effects on tumor cell lines in vitro, effects on immune cells in vivo, and antitumor effects on tumor-bearing mice with prolonged survival periods.

  15. STING-Dependent Cytosolic DNA Sensing Promotes Radiation-Induced Type I Interferon-Dependent Antitumor Immunity in Immunogenic Tumors.

    Science.gov (United States)

    Deng, Liufu; Liang, Hua; Xu, Meng; Yang, Xuanming; Burnette, Byron; Arina, Ainhoa; Li, Xiao-Dong; Mauceri, Helena; Beckett, Michael; Darga, Thomas; Huang, Xiaona; Gajewski, Thomas F; Chen, Zhijian J; Fu, Yang-Xin; Weichselbaum, Ralph R

    2014-11-20

    Ionizing radiation-mediated tumor regression depends on type I interferon (IFN) and the adaptive immune response, but several pathways control I IFN induction. Here, we demonstrate that adaptor protein STING, but not MyD88, is required for type I IFN-dependent antitumor effects of radiation. In dendritic cells (DCs), STING was required for IFN-? induction in response to irradiated-tumor cells. The cytosolic DNA sensor cyclic GMP-AMP (cGAMP) synthase (cGAS) mediated sensing of irradiated-tumor cells in DCs. Moreover, STING was essential for radiation-induced adaptive immune responses, which relied on type I IFN signaling on DCs. Exogenous IFN-? treatment rescued the cross-priming by cGAS or STING-deficient DCs. Accordingly, activation of STING by a second messenger cGAMP administration enhanced antitumor immunity induced by radiation. Thus radiation-mediated antitumor immunity in immunogenic tumors requires a functional cytosolic DNA-sensing pathway and suggests that cGAMP treatment might provide a new strategy to improve radiotherapy. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. Cisplatin as an Anti-Tumor Drug: Cellular Mechanisms of Activity, Drug Resistance and Induced Side Effects

    International Nuclear Information System (INIS)

    Florea, Ana-Maria; Büsselberg, Dietrich

    2011-01-01

    Platinum complexes are clinically used as adjuvant therapy of cancers aiming to induce tumor cell death. Depending on cell type and concentration, cisplatin induces cytotoxicity, e.g., by interference with transcription and/or DNA replication mechanisms. Additionally, cisplatin damages tumors via induction of apoptosis, mediated by the activation of various signal transduction pathways, including calcium signaling, death receptor signaling, and the activation of mitochondrial pathways. Unfortunately, neither cytotoxicity nor apoptosis are exclusively induced in cancer cells, thus, cisplatin might also lead to diverse side-effects such as neuro- and/or renal-toxicity or bone marrow-suppression. Moreover, the binding of cisplatin to proteins and enzymes may modulate its biochemical mechanism of action. While a combination-chemotherapy with cisplatin is a cornerstone for the treatment of multiple cancers, the challenge is that cancer cells could become cisplatin-resistant. Numerous mechanisms of cisplatin resistance were described including changes in cellular uptake, drug efflux, increased detoxification, inhibition of apoptosis and increased DNA repair. To minimize cisplatin resistance, combinatorial therapies were developed and have proven more effective to defeat cancers. Thus, understanding of the biochemical mechanisms triggered by cisplatin in tumor cells may lead to the design of more efficient platinum derivates (or other drugs) and might provide new therapeutic strategies and reduce side effects

  17. Cisplatin as an Anti-Tumor Drug: Cellular Mechanisms of Activity, Drug Resistance and Induced Side Effects

    Energy Technology Data Exchange (ETDEWEB)

    Florea, Ana-Maria [Department of Neuropathology, Heinrich-Heine University, Düsseldorf (Germany); Büsselberg, Dietrich, E-mail: dib2015@qatar-med.cornell.edu [Weil Cornell Medical College in Qatar, Qatar Foundation-Education City, P.O. Box 24144, Doha (Qatar)

    2011-03-15

    Platinum complexes are clinically used as adjuvant therapy of cancers aiming to induce tumor cell death. Depending on cell type and concentration, cisplatin induces cytotoxicity, e.g., by interference with transcription and/or DNA replication mechanisms. Additionally, cisplatin damages tumors via induction of apoptosis, mediated by the activation of various signal transduction pathways, including calcium signaling, death receptor signaling, and the activation of mitochondrial pathways. Unfortunately, neither cytotoxicity nor apoptosis are exclusively induced in cancer cells, thus, cisplatin might also lead to diverse side-effects such as neuro- and/or renal-toxicity or bone marrow-suppression. Moreover, the binding of cisplatin to proteins and enzymes may modulate its biochemical mechanism of action. While a combination-chemotherapy with cisplatin is a cornerstone for the treatment of multiple cancers, the challenge is that cancer cells could become cisplatin-resistant. Numerous mechanisms of cisplatin resistance were described including changes in cellular uptake, drug efflux, increased detoxification, inhibition of apoptosis and increased DNA repair. To minimize cisplatin resistance, combinatorial therapies were developed and have proven more effective to defeat cancers. Thus, understanding of the biochemical mechanisms triggered by cisplatin in tumor cells may lead to the design of more efficient platinum derivates (or other drugs) and might provide new therapeutic strategies and reduce side effects.

  18. The mathematics of random mutation and natural selection for multiple simultaneous selection pressures and the evolution of antimicrobial drug resistance.

    Science.gov (United States)

    Kleinman, Alan

    2016-12-20

    The random mutation and natural selection phenomenon act in a mathematically predictable behavior, which when understood leads to approaches to reduce and prevent the failure of the use of these selection pressures when treating infections and cancers. The underlying principle to impair the random mutation and natural selection phenomenon is to use combination therapy, which forces the population to evolve to multiple selection pressures simultaneously that invoke the multiplication rule of probabilities simultaneously as well. Recently, it has been seen that combination therapy for the treatment of malaria has failed to prevent the emergence of drug-resistant variants. Using this empirical example and the principles of probability theory, the derivation of the equations describing this treatment failure is carried out. These equations give guidance as to how to use combination therapy for the treatment of cancers and infectious diseases and prevent the emergence of drug resistance. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  19. Comparison of two self-assembled macromolecular prodrug micelles with different conjugate positions of SN38 for enhancing antitumor activity

    Directory of Open Access Journals (Sweden)

    Liu Y

    2015-03-01

    Full Text Available Yi Liu,1 Hongyu Piao,1 Ying Gao,1 Caihong Xu,2 Ye Tian,1 Lihong Wang,1 Jinwen Liu,1 Bo Tang,1 Meijuan Zou,1 Gang Cheng1 1Department of Pharmaceutics, Shenyang Pharmaceutical University, Shenyang, Liaoning Province, People’s Republic of China; 2Department of Food Science, Shenyang Normal University, Shenyang, Liaoning Province, People’s Republic of China Abstract: 7-Ethyl-10-hydroxycamptothecin (SN38, an active metabolite of irinotecan (CPT-11, is a remarkably potent antitumor agent. The clinical application of SN38 has been extremely restricted by its insolubility in water. In this study, we successfully synthesized two macromolecular prodrugs of SN38 with different conjugate positions (chitosan-(C10-OHSN38 and chitosan-(C20-OHSN38 to improve the water solubility and antitumor activity of SN38. These prodrugs can self-assemble into micelles in aqueous medium. The particle size, morphology, zeta potential, and in vitro drug release of SN38 and its derivatives, as well as their cytotoxicity, pharmacokinetics, and in vivo antitumor activity in a xenograft BALB/c mouse model were studied. In vitro, chitosan-(C10-OHSN38 (CS-(10sSN38 and chitosan-(C20-OHSN38 (CS-(20sSN38 were 13.3- and 25.9-fold more potent than CPT-11 in the murine colon adenocarcinoma cell line CT26, respectively. The area under the curve (AUC0–24 of SN38 after intravenously administering CS-(10sSN38 and CS-(20sSN38 to Sprague Dawley rats was greatly improved when compared with CPT-11 (both P<0.01. A larger AUC0–24 of CS-(20sSN38 was observed when compared to CS-(10sSN38 (P<0.05. Both of the novel self-assembled chitosan-SN38 prodrugs demonstrated superior anticancer activity to CPT-11 in the CT26 xenograft BALB/c mouse model. We have also investigated the differences between these macromolecular prodrug micelles with regards to enhancing the antitumor activity of SN38. CS-(20sSN38 exhibited better in vivo antitumor activity than CS-(10sSN38 at a dose of 2.5 mg/kg (P<0

  20. Antitumor effects of Marginisporum crassissimum (Rhodophyceae), a marine red alga.

    Science.gov (United States)

    Hiroishi, S; Sugie, K; Yoshida, T; Morimoto, J; Taniguchi, Y; Imai, S; Kurebayashi, J

    2001-06-26

    Marginisporum crassissimum (Yendo) Ganesan, a marine red alga found in the ordinal coastal sea around Japan, revealed antitumor (antimetastatic) effects in vitro and in vivo. In in vitro experiments, extracts of this alga inhibited not only the growth of several tumor cell lines, such as B16-BL6 (a mouse melanoma cell line), JYG-B (a mouse mammary carcinoma cell line) and KPL-1 (a human mammary carcinoma cell line), but also invasion of B16-BL6 cells in a culture system. In in vivo experiments, the lung metastasis of B16-BL6 cells inoculated to the tail vein of B57BL/6J mice was inhibited by intraperitoneal administration of an extract from the alga. In addition, life prolongation of B57BL/6J mice inoculated with B16-BL6 cells was also observed by the intraperitoneal administration of the extract. An effective substance showing B16-BL6 growth inhibition in vitro was partially purified by filtration and hydrophobic column chromatography, and was revealed to be sensitive to trypsin-digestion and heat-treatment. The molecular weight of the substance was greater than 100 kDa. This is the first study demonstrating antitumor (antimetastatic) effects of M. crassissimum.

  1. Binding and internalization of NGR-peptide-targeted liposomal doxorubicin (TVT-DOX) in CD13-expressing cells and its antitumor effects.

    Science.gov (United States)

    Garde, Seema V; Forté, André J; Ge, Michael; Lepekhin, Eugene A; Panchal, Chandra J; Rabbani, Shafaat A; Wu, Jinzi J

    2007-11-01

    In an effort to develop new agents and molecular targets for the treatment of cancer, aspargine-glycine-arginine (NGR)-targeted liposomal doxorubicin (TVT-DOX) is being studied. The NGR peptide on the surface of liposomal doxorubicin (DOX) targets an aminopeptidase N (CD13) isoform, specific to the tumor neovasculature, making it a promising strategy. To further understand the molecular mechanisms of action, we investigated cell binding, kinetics of internalization as well as cytotoxicity of TVT-DOX in vitro. We demonstrate the specific binding of TVT-DOX to CD13-expressing endothelial [human umbilical vein endothelial cells (HUVEC) and Kaposi sarcoma-derived endothelial cells (SLK)] and tumor (fibrosarcoma, HT-1080) cells in vitro. Following binding, the drug was shown to internalize through the endosomal pathway, eventually leading to the localization of doxorubicin in cell nuclei. TVT-DOX showed selective toxicity toward CD13-expressing HUVEC, sparing the CD13-negative colon-cancer cells, HT-29. Additionally, the nontargeted counterpart of TVT-DOX, Caelyx, was less cytotoxic to the CD13-positive HUVECs demonstrating the advantages of NGR targeting in vitro. The antitumor activity of TVT-DOX was tested in nude mice bearing human prostate-cancer xenografts (PC3). A significant growth inhibition (up to 60%) of PC3 tumors in vivo was observed. Reduction of tumor vasculature following treatment with TVT-DOX was also apparent. We further compared the efficacies of TVT-DOX and free doxorubicin in the DOX-resistant colon-cancer model, HCT-116, and observed the more pronounced antitumor effects of the TVT-DOX formulation over free DOX. The potential utility of TVT-DOX in a variety of vascularized solid tumors is promising.

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

    Directory of Open Access Journals (Sweden)

    Daniel V Correia

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

  3. Extraction of a Novel Cold-Water-Soluble Polysaccharide from Astragalus membranaceus and Its Antitumor and Immunological Activities

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    An-jun Liu

    2017-12-01

    Full Text Available The polysaccharides of Astragalus membranaceus have received extensive study and attention, but there have been few reports on the extraction of these polysaccharides using cold water (4 °C. In this study, we fractionated a novel cold-water-soluble polysaccharide (cAMPs-1A from Astragalus membranaceus with a 92.00% carbohydrate content using a DEAE-cellulose 52 anion exchange column and a Sephadex G-100 column. Our UV, Fourier-transform infrared spectroscopy (FTIR, high-performance gel permeation chromatography, and ion chromatography analysis results indicated the monosaccharide composition of cAMPs-1A with 1.23 × 104 Da molecular weight to be fucose, arabinose, galactose, glucose, and xylose, with molar ratios of 0.01:0.06:0.20:1.00:0.06, respectively. The UV spectroscopy detected no protein and nucleic acid in cAMPs-1A. We used FTIR analysis to characterize the α-d-pyranoid configuration in cAMPs-1A. In addition, we performed animal experiments in vivo to evaluate the antitumor and immunomodulatory effects of cAMPs-1A. The results suggested that cAMPs-1A oral administration could significantly inhibit tumor growth with the inhibitory rate of 20.53%, 36.50% and 44.49%, respectively, at the dosage of 75,150, and 300 mg/kg. Moreover, cAMPs-1A treatment could also effectively protect the immune organs, promote macrophage pinocytosis, and improve the percentages of lymphocyte subsets in the peripheral blood of tumor-bearing mice. These findings demonstrate that the polysaccharide cAMPs-1A has an underlying application as natural antitumor agents.

  4. Scoparone exerts anti-tumor activity against DU145 prostate cancer cells via inhibition of STAT3 activity.

    Directory of Open Access Journals (Sweden)

    Jeong-Kook Kim

    Full Text Available Scoparone, a natural compound isolated from Artemisia capillaris, has been used in Chinese herbal medicine to treat neonatal jaundice. Signal transducer and activator of transcription 3 (STAT3 contributes to the growth and survival of many human tumors. This study was undertaken to investigate the anti-tumor activity of scoparone against DU145 prostate cancer cells and to determine whether its effects are mediated by inhibition of STAT3 activity. Scoparone inhibited proliferation of DU145 cells via cell cycle arrest in G1 phase. Transient transfection assays showed that scoparone repressed both constitutive and IL-6-induced transcriptional activity of STAT3. Western blot and quantitative real-time PCR analyses demonstrated that scoparone suppressed the transcription of STAT3 target genes such as cyclin D1, c-Myc, survivin, Bcl-2, and Socs3. Consistent with this, scoparone decreased phosphorylation and nuclear accumulation of STAT3, but did not reduce phosphorylation of janus kinase 2 (JAK2 or Src, the major upstream kinases responsible for STAT3 activation. Moreover, transcriptional activity of a constitutively active mutant of STAT3 (STAT3C was inhibited by scoparone, but not by AG490, a JAK2 inhibitor. Furthermore, scoparone treatment suppressed anchorage-independent growth in soft agar and tumor growth of DU145 xenografts in nude mice, concomitant with a reduction in STAT3 phosphorylation. Computational modeling suggested that scoparone might bind the SH2 domain of STAT3. Our findings suggest that scoparone elicits an anti-tumor effect against DU145 prostate cancer cells in part through inhibition of STAT3 activity.

  5. Engineering Microbial Cells for the Biosynthesis of Natural Compounds of Pharmaceutical Significance

    Directory of Open Access Journals (Sweden)

    Philippe Jeandet

    2013-01-01

    Full Text Available Microbes constitute important platforms for the biosynthesis of numerous molecules of pharmaceutical interest such as antitumor, anticancer, antiviral, antihypertensive, antiparasitic, antioxidant, immunological agents, and antibiotics as well as hormones, belonging to various chemical families, for instance, terpenoids, alkaloids, polyphenols, polyketides, amines, and proteins. Engineering microbial factories offers rich opportunities for the production of natural products that are too complex for cost-effective chemical synthesis and whose extraction from their originating plants needs the use of many solvents. Recent progresses that have been made since the millennium beginning with metabolic engineering of microorganisms for the biosynthesis of natural products of pharmaceutical significance will be reviewed.

  6. Oral JS-38, a metabolite from Xenorhabdus sp., has both anti-tumor activity and the ability to elevate peripheral neutrophils.

    Science.gov (United States)

    Liu, Min-Yu; Xiao, Lin; Chen, Geng-Hui; Wang, Yong-Xiang; Xiong, Wei-Xia; Li, Fei; Liu, Ying; Huang, Xiao-Ling; Deng, Yi-Fang; Zhang, Zhen; Sun, Hai-Yan; Liu, Quan-Hai; Yin, Ming

    2014-10-01

    JS-38 (mitothiolore), a synthetic version of a metabolite isolated from Xenorhabdus sp., was evaluated for its anti-tumor and white blood cell (WBC) elevating activities. These anti-proliferative activities were assessed in vitro using a panel of ten cell lines. The anti-tumor activities were tested in vivo using B16 allograft mouse models and xenograft models of A549 human lung carcinoma and QGY human hepatoma in nude mice. The anti-tumor interactions of JS-38 and cyclophosphamide (CTX) or 5-fluorouracil (5-Fu) were studied in a S180 sarcoma model in ICR mice. Specific stimulatory effects were determined on peripheral neutrophils in normal and CTX- and 5-Fu-induced neutropenic mice. The IC50 values ranged from 0.1 to 2.0 μmol·L(-1). JS-38 (1 μmol·L(-1)) caused an increase in A549 tumor cell apoptosis. Multi-daily gavage of JS-38 (15, 30, and 60 mg·kg(-1)·d(-1)) inhibited in vivo tumor progression without a significant effect on body weight. JS-38 additively enhanced the in vivo anti-tumor effects of CTX or 5-Fu. JS-38 increased peripheral neutrophil counts and neutrophil rates in normal BALB/c mice almost as effectively as granulocyte colony-stimulating factor (G-CSF). In mice with neutropenia induced by CTX or 5-Fu, JS-38 rapidly restored neutrophil counts. These results suggest that JS-38 has anti-tumor activity, and also has the ability to increase peripheral blood neutrophils. Copyright © 2014 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.

  7. Structural organization of C{sub 60} fullerene, doxorubicin, and their complex in physiological solution as promising antitumor agents

    Energy Technology Data Exchange (ETDEWEB)

    Prylutskyy, Yu. I. [Taras Shevchenko National University of Kyiv (Ukraine); Evstigneev, M. P., E-mail: max-evstigneev@mail.ru [Belgorod State University, Department of Biology and Chemistry (Russian Federation); Cherepanov, V. V. [Institute of Physics of NAS of Ukraine (Ukraine); Kyzyma, O. A.; Bulavin, L. A.; Davidenko, N. A. [Taras Shevchenko National University of Kyiv (Ukraine); Scharff, P. [Ilmenau University of Technology (Germany)

    2015-01-15

    Specific features of structural self-organization of C{sub 60} fullerene (1 nm size range), antitumor antibiotic doxorubicin (Dox) and their complex in physiological solution (0.9 % NaCl) have been investigated by means of atomic-force microscopy, dynamic light scattering, and small-angle X-ray scattering. Significant ordering of the mixed system, C{sub 60} + Dox, was observed, suggesting the complexation between these drugs, and giving insight into the mechanism of enhancement of Dox antitumor effect on simultaneous administration with C{sub 60} fullerene.

  8. EGF receptor targeted lipo-oligocation polyplexes for antitumoral siRNA and miRNA delivery

    Science.gov (United States)

    Müller, Katharina; Klein, Philipp M.; Heissig, Philipp; Roidl, Andreas; Wagner, Ernst

    2016-11-01

    Antitumoral siRNA and miRNA delivery was demonstrated by epidermal growth factor receptor (EGFR) targeted oligoaminoamide polyplexes. For this purpose, the T-shaped lipo-oligomer 454 was used to complex RNA into a core polyplex, which was subsequently functionalized with the targeting peptide ligand GE11 via a polyethylene glycol (PEG) linker. To this end, free cysteines on the surface of 454 polyplex were coupled with a maleimide-PEG-GE11 reagent (Mal-GE11). Resulting particles with sizes of 120-150 nm showed receptor-mediated uptake into EGFR-positive T24 bladder cancer cells, MDA-MB 231 breast cancer cells and Huh7 liver cancer cells. Furthermore, these formulations led to ligand-dependent gene silencing. RNA interference (RNAi) triggered antitumoral effects were observed for two different therapeutic RNAs, a miRNA-200c mimic or EG5 siRNA. Using polyplexes modified with a ratio of 0.8 molar equivalents of Mal-GE11, treatment of T24 or MDA-MB 231 cancer cells with miR-200c led to the expected decreased proliferation and migration, changes in cell cycle and enhanced sensitivity towards doxorubicin. Delivery of EG5 siRNA into Huh7 cells resulted in antitumoral activity with G2/M arrest, triggered by loss of mitotic spindle separation and formation of mono-astral spindles. These findings demonstrate the potential of GE11 ligand-containing RNAi polyplexes for cancer treatment.

  9. Effect of electron beam-irradiation to b-glucan on its immunomodulating and antitumor activity

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Yeon Hwan; Lee, Jung Lim; Yoo, Yung Choon [Konyand Univ., Daejeon (Korea, Republic of); Kim, Jae Hoon; Lee, Ju Woon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2010-07-01

    In this study, in order investigated the effect of electron beam irradiation to b-glucan on its biological activities, we compared immunomodulating and antitumor activity between non-irradiated and electron beam-irradiated b-glucan. EB-glucan was irradiated by electron beam with 10, 30 and 50 kGy. Treatment with EB-glucan resulted in a slight increase of the proliferation of ConA-stimulated splenocytes, and the strongest activity was seen in 50 kGy-treated EB-glucan. EB-glucan teated with 50 kGy also showed increased secretion of cytokines such as IL-2 IFN-{gamma} and IL-6 from ConA-stimulated splenocytes. The activity of EB-glucan to enhance the proliferation of splenocytes and cytokine secretion from ConA-stimulated splenocytes was higher than that of NI-glucan. Furthermore, EB-glucan treated with 50 kGy showed higher activity to activate RAW 264.7 macrophages, comparing with that of NI-glucan. In experiments of antitumor activity, EB-glucan treated with 50 kGy prior to tumor inoculation inhibited an experimental lung metastasis produced by B16-BL6 melanoma cells in mice. But NI-glucan did show no effect. In addition, EB-glucan treated with 50 kGy induced a decrease a decrease of tumor growth in tumor-bearing mice. Collectivelt, these results indicates that electron beam irradiation {beta}-glucan leads its biological functions to enhance immunomodulating and antitumor activity.

  10. Effect of electron beam-irradiation to b-glucan on its immunomodulating and antitumor activity

    International Nuclear Information System (INIS)

    Jung, Yeon Hwan; Lee, Jung Lim; Yoo, Yung Choon; Kim, Jae Hoon; Lee, Ju Woon

    2010-01-01

    In this study, in order investigated the effect of electron beam irradiation to b-glucan on its biological activities, we compared immunomodulating and antitumor activity between non-irradiated and electron beam-irradiated b-glucan. EB-glucan was irradiated by electron beam with 10, 30 and 50 kGy. Treatment with EB-glucan resulted in a slight increase of the proliferation of ConA-stimulated splenocytes, and the strongest activity was seen in 50 kGy-treated EB-glucan. EB-glucan teated with 50 kGy also showed increased secretion of cytokines such as IL-2 IFN-γ and IL-6 from ConA-stimulated splenocytes. The activity of EB-glucan to enhance the proliferation of splenocytes and cytokine secretion from ConA-stimulated splenocytes was higher than that of NI-glucan. Furthermore, EB-glucan treated with 50 kGy showed higher activity to activate RAW 264.7 macrophages, comparing with that of NI-glucan. In experiments of antitumor activity, EB-glucan treated with 50 kGy prior to tumor inoculation inhibited an experimental lung metastasis produced by B16-BL6 melanoma cells in mice. But NI-glucan did show no effect. In addition, EB-glucan treated with 50 kGy induced a decrease a decrease of tumor growth in tumor-bearing mice. Collectivelt, these results indicates that electron beam irradiation β-glucan leads its biological functions to enhance immunomodulating and antitumor activity

  11. Development and Characterization of a Humanized Anti-HER2 Antibody HuA21 with Potent Anti-Tumor Properties in Breast Cancer Cells

    Directory of Open Access Journals (Sweden)

    Ruilin Li

    2016-04-01

    Full Text Available Human epidermal growth factor receptor 2 (HER2 is one of the most studied tumor-associated antigens for cancer immunotherapy. An engineered anti-HER-2 chimeric A21 antibody (chA21 is a chimeric antibody targeted to subdomain I of the HER2 extracellular domain. Here, we report the anti-tumor activity of the novel engineered monoclonal antibody humanized chA21 (HuA21 that targets HER2 on the basis of chA21, and we describe the underlying mechanisms. Our results reveal that HuA21 markedly inhibits the proliferation and migration of HER2-overexpressing breast cancer cells and causes enhanced antibody-dependent cell-mediated cytotoxicity potency against HER2-overexpressing tumor cells. In particular, HuA21, but not trastuzumab (Tra, markedly suppresses growth and enhances the internalization of the antibody in Tra-resistant BT-474 breast cancer cells. These characteristics are highly associated with the intrinsic ability of HuA21 to down-regulate HER2 activation and inhibit the extracellular signal-regulated kinase 1/2 (ERK1/2 and protein kinase B (Akt signaling pathways. Furthermore, the combination of HuA21 with Tra synergistically enhances the anti-tumor effects in vitro and in vivo and inhibits HER2 activation and the ERK1/2 and Akt signaling pathways. Altogether, our results suggest that HuA21 may represent a unique anti-HER2 antibody with potential as a therapeutic candidate alone or in combination with other anti-HER2 reagents in cancer therapy.

  12. Study on in vitro anti-tumor activity of Bidens bipinnata L. extract ...

    African Journals Online (AJOL)

    We studied the in vitro anti-tumor activity of Bidens Bipinnata L. extract. MTT assay was used to investigate the inhibitory effect of different concentrations of the extracts on human hepatocellular carcinoma (HepG2) cell lines and human cervical carcinoma (Hela) cell lines, and the IC50 values were calculated. The Bidens ...

  13. Peeking at ecosystem stability: making use of a natural disturbance experiment to analyze resistance and resilience.

    Science.gov (United States)

    Bruelheide, Helge; Luginbühl, Ute

    2009-05-01

    To determine which factors contribute most to the stability of species composition in a beech forest after profound disturbance, we made use of a natural experiment caused by a severe windthrow that occurred at a permanent monitoring site in an old beech forest in Lower Saxony (Germany). The floristic composition was recorded for the succeeding five years after the disturbance and used to derive measures of resistance and resilience for plots as well as for individual species. Due to the existence of previously established randomly distributed permanent plots, we had precise information of the pre-disturbance state, including initial cover of the herb layer, species richness, and species composition. Variables describing the floristic change, resistance, and resilience were derived from correspondence analysis allowing for partitioning the effects of variation among plots from those of temporal change. We asked to which degree these variables could be predicted by pre-disturbance state and disturbance intensity. We found that both the pre-disturbance state and the disturbance intensity were good predictors for floristic change and resistance, while they failed to predict resilience. Among the descriptors of the pre-disturbance state the initial cover of the herb layer turned out to be a useful predictor, which is explained by a high vegetation cover buffering against losses and preventing establishment of newcomers. In contrast, species number neither showed a relationship to floristic change nor to resistance. Putative positive effects of species number on stability according to the insurance hypothesis might have been counterbalanced by a disruption of niche complementarity in species-rich communities. Among the descriptors of disturbance intensity, the loss in canopy cover and the change in photosynthetically active radiation after the storm were equally good predictors for the change in floristic composition and resistance. The analysis of the responses of

  14. Antitumor activity and carrier properties of novel hemocyanins coupled to a mimotope of GD2 ganglioside.

    Science.gov (United States)

    Palacios, Miriam; Tampe, Ricardo; Del Campo, Miguel; Zhong, Ta-Ying; López, Mercedes N; Salazar-Onfray, Flavio; Becker, María Inés

    2018-04-25

    Conjugation to carrier proteins is a way to improve the immunogenicity of peptides. Such is the case for peptides mimicking carbohydrate tumor-associated antigens in cancer vaccine development. The most used protein for this purpose is the keyhole limpet hemocyanin (KLH) from Megathura crenulata. Its limited bioavailability has prompted interest in finding new candidates; nevertheless, it is not known whether other hemocyanins might be equally efficient as carrier of carbohydrate peptide mimotopes to promotes anti-tumor responses. Here, we evaluated the carrier and antitumor activity of novel hemocyanins with documented immunogenicity obtained from Concholepas concholepas (CCH) and Fissurella latimarginata (FLH), coupled through sulfo-SMCC to P10, a mimetic peptide of GD2, the major ganglioside constituent of neuroectodermal tumors, and incorporating AddaVax as an adjuvant. The humoral immune responses of mice showed that CCH-P10 and FLH-P10 conjugates elicited specific IgM and IgG antibodies against P10 mimotope, similar to those obtained with KLH-P10, which was used as a positive control. The CCH-P10 and FLH-P10 antisera, exhibited cross-reactivity with murine and human melanoma cells, like anti-CCH and anti-FLH sera suggesting a cross-reaction of CCH and FLH glycosylations with carbohydrate epitopes on the tumor cell surfaces, similar to the KLH antisera. When mice were primed with each hemocyanin-P10 and challenged with melanoma cells, better antitumor effects were observed for FLH-P10 than for CCH-P10 and, as for KLH-P10, irrespective of conjugation. These data demonstrate that CCH and FLH are useful carriers of carbohydrate mimotopes; however, the best antitumor activity of FLH preparations, indicate that is a suitable candidate for further cancer vaccines research. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  15. Carcinogenic and antitumor effects of aminotriazole on acatalasemic and normal catalase mice

    International Nuclear Information System (INIS)